BIOPROGRESSIVE THERAPY INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com
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Introduction The Management Umbrella Principles of Bioprogressive Therapy Visual Treatment Objective The Use of Superimposition Areas Orthopedics in Bioprogressive Therapy The Utility and Sectional Arches Bioprogressive Mixed Dentition Treatment Mechanics Sequence for Extraction Cases Mechanics Sequence for Class II Division 1 Cases Mechanics Sequence for Class II Division 2 Cases www.indiandentalacademy.com Finishing Procedures and Retention
Bioprogressive Therapy was originated by Drs. Robert Ricketts and Ruel Bench who combined contemporary edgewise mechanics with solid diagnostic principles and an innovative approach to sectional mechanics. Bioprogressive Therapy accepts as its mission the treatment of the total face rather than the narrower objective of the teeth or the occlusion. Although the teeth and the occlusion are of critical importance in achieving the broader goal of treating and improving the face, orthodontic therapies must be designed to be applied appropriately to specific facial types, muscular patterns, and functional needs of individuals. The relationship of the jaws to each other, with the resulting convexity or concavity of the profile, suggests the orthopedic alteration that will be required to achieve the desired result. The progressive unfolding of these arches, in conjunction with the purposeful alterations resulting from orthodontic therapy, combine to produce the desired outcomes as they relate to aesthetic effect, www.indiandentalacademy.com occlusal and respiratory function.
Basic to an understanding of these potential changes is the dynamics of growth and function under normal relationships with an appreciation for a range of variation from the normal as applied to the individual with his specific needs and potential. Dr. Ricketts' orthodontic philosophy and therapy involves a broad concept of total treatment, rather than a sequence of technical and mechanical steps. Referred to as BioProgressive Therapy, it takes advantage of biological progressions including growth, development, and function, and directs them in a fashion that normalizes function and enhances aesthetic effect.
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THE MANAGEMENT UMBRELLA CONCEPT The management umbrella comprises of the following
Planning Organizing Leading Controlling Allen management system
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JCO 1977; 11(9): 616-627
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JCO 1977; 11(9): 616-627
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JCO 1977; 11(9): 616-627
www.indiandentalacademy.com
JCO 1977; 11(9): 616-627
www.indiandentalacademy.com
JCO 1977; 11(9): 616-627
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JCO 1977; 11(9): 616-627
PRINCIPLES OF BIOPROGRESSIVE THERAPY 1. The use of a systems approach to diagnosis and treatment by the application of the visual treatment objective in planning treatment, evaluating anchorage and monitoring results. 2. Torque control throughout treatment. 3. Muscular and cortical bone anchorage. 4. Movement of all teeth in any direction with the proper application of pressure. 5. Orthopedic alteration.
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6. Treat
the overbite before the overjet correction.
7. Sectional arch therapy. 8. Concept of overtreatment. 9. Unlocking the malocclusion in a progressive sequence of treatment in order to establish or restore more normal function. 10. Efficiency in treatment with quality results, utilizing a concept of prefabrication of appliances.
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#1. The use of a systems approach to diagnosis and treatment by the application of the visual treatment objective in planning treatment, evaluating anchorage, and monitoring results. TREATMENT MANAGEMENT CYCLE
This management cycle when applied to treatment, demonstrates the many values in treatment design and specific treatment planning; execution, feedback and analysis. All are interrelated in establishing procedures for continual improvement and progress
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TREATMENT DESIGN Descriptive Analysis+Examination = Diagnosis VTO Five Position growth and treatment analysis Design progressive sequence of treatment
ANALYSIS OF RESULTS
EXECUTION OF TREATMENT
1.Retention tracing evaluated with
Functional correction
•Projected non Rx tracing
Orthopedic correction
•Goals of the VTO tracing
Arch length requirements
2. Identify growth from Rx changes
Extraction anchorage needs
•To identify abnormal growth variations
Sequence of progressive mechanics
•To acknowledge unexpected Rx
Programmed treatment
•To verify expected growth and Rx
TREATMENT PROGRESS FEEDBACK Mid treatment tracing to monitor progress Mid treatment tracing superimposed between beginning and VTO tracings www.indiandentalacademy.com
Mid treatment evaluation and correction if necessary
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#2. Torque control throughout treatment. Bio Progressive Therapy mentions four treatment situations where torque control of the root movement is necessary: 1. Keep roots in vascular trabecular bone— for efficient movement. For beginning movements, such as incisor intrusion or cuspid retraction— where movement through a less dense trabecular bone structure is desired because it is more efficient— torque control allows us to steer the roots away from the denser, thicker cortical bone, and through the less dense channels of the vascular trabecular bone.
2. Place roots against dense cortical bone— for anchorage. Torque control of teeth being anchored or stabilized against movement is done by placing their roots in juxtaposition against the more dense cortical bone. www.indiandentalacademy.com
JCO 1977; 11(10): 661-682
3. Torque to remodel cortical bone Repositioning of the teeth often require that the roots must be moved into the dense, less vascular cortical bone structure. Examples of such situations are: a. Upper and lower incisor retraction through the dense lingual cortical plates; b. Upper incisor root torquing movements; c. Impacted upper cuspids, either in the palate or high in the labial vestibule; d. Forward movement of lower molars to close spaces created by missing or extracted teeth. 4. Torque used to position teeth in final occlusion details. The fourth situation where torque control of the root is desired is during the final stages of treatment where the final details of occlusion are being established, where fit and mesh of the teeth require proper root alignment for proper function and better stability.
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#3. Muscular and cortical bone anchorage Muscular Anchorage ď‚ŻStabilizing the teeth against the horizontal movements and also against vertical or extruding forces produced by a cervical headgear to the upper molars is countered by the posterior muscles of mastication, primarily the masseters and temporalis. ď‚ŻTreatment procedures in individuals with weaker muscular support should be monitored and modified to compensate for weaker anchorage support.
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Cortical Bone Anchorage Tooth movement can be further delayed where excess forces against the cortical bone can press out the blood supply and limit the physiology and the tooth movement. Bio-Progressive Therapy applies this principle of cortical bone anchorage in stabilizing the teeth in those areas where it desires to limit their movement. Lower molar anchorage is enhanced by expanding the molar roots into the dense cortical bone on their buccal surface. Excessive buccal root torque and expansion is placed in the arch wires to locate the roots into the cortical bone. The upper molar that is adjacent to the zygomatic ridge, the maxillary sinus, and the cortical bone shelves of the alveolar process needs to be anchored and stabilized for use in orthopedic alterations www.indiandentalacademy.com
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#4.Movement of any tooth in any direction with the proper application of pressure BPT maintains that forces that are lighter allow for the blood supply to sustain cell physiology enabling more efficient tooth movement as compared to heavier forces. Brian Lee, following the work of Storey and Smith in Australia, has suggested that the most efficient force for tooth movement is based upon the size of the root surface of the tooth to be moved, which he called the enface root surface or the portion of the root that is in the direction of movement. BPT suggests that the force can be reduced by one half, to 100gms/cm2 of enface root surface. Density of the supportive bone is also an influencing factor in the rate of tooth movement.
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#5. Orthopedic alteration Orthopedic alteration changes the relationship of the basic supporting jaw structure, as contrasted to tooth movement in the more localized area of the alveolar process. Orthopedic change or alteration of the supporting structure usually is associated with treatment of the younger child. Orthopedic alteration brings about changes in the maxilla and compensatory changes in the mandible and TMJ. Expected mandibular rotation and facial type usually dictate the kind of headgear prescribed.
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JCO 1977; 11(10): 661-682
#6 Treat the overbite before the overjet. Incisor overbite correction can be accomplished by two methods. 1. Extrusion of posterior teeth, which increases the lower face height by mandibular rotation. 2. Intrusion of the upper or lower incisor teeth, with little or no mandibular rotation. ď‚Ż BPT mechanics finds that incisor intrusion is the treatment of choice
for the best results not only during treatment, but also for stability of results and optimizing function Often another complication of overbite interference during treatment is the distal displacement of the condyle in the fossa resulting in temperomandibular joint dysfunction and incisor instability due to traumatic interference of the incisor deep bite occlusion. www.indiandentalacademy.com
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#7 Sectional arch treatment. Sectional arch treatment is a basic treatment procedure of BPT in which the arches are broken into sections or segments in order that the application of force in direction and amount will be of more benefit in the efficient movements of the teeth. There are four benefits of sectional arch treatment: 1. It allows lighter continuous forces to be directed to the individual teeth (for their efficient movement). 2. More effective root control in the basic tooth movements. 3. It supplements maxillary orthopedic alteration. 4. It reduces the binding and friction of the brackets as they slide along the arch wire. www.indiandentalacademy.com
JCO 1977; 11(10): 661-682
#8 Concept of overtreatment. BPT suggests four areas where the concept of overtreatment may help compensate for the anticipated post-treatment adjustments: 1. To overcome muscular forces against the tooth surfaces. a)Over expansion also encourages the tongue to elevate and function in support of the dental arches. b) Overclosure of an anterior open bite. c) Overtreatment of the incisor overjet and interincisal angle in lip sucking habits, 2. Root movements needed for stability. ď‚ŻIncisor deep overbite treatment benefits in its stability by over intrusion and overtorquing. ď‚Ż Paralleling of the roots of the teeth adjacent to extraction sites is important to the stability of space closure. ď‚ŻSevere rotation, where periodontal ligaments exhibit elastic action that can have prolonged post-treatment influence, needs over-rotation of the roots to help compensate for the relapse effect. www.indiandentalacademy.com
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3. To overcome orthopedic rebound. Rebound of orthopedic corrections may be beneficial or may compound the problem. In Class II treatment the rebound effect which closes the bite and rotates the chin forward will help in Class II correction. In Class III treatment correction this rotation would compound the problem. 4. To allow settling in retention. Overtreatment of the individual teeth within the arches allows them to "settle" into a functioning occlusion. In BPT, retainers then are considered active appliances and are adjusted to allow this settling action to take place, rather than to just hold or maintain teeth. Overtreatment of the typical Class II correction begins with the molars by overtreating them into a "super Class I" through distal rotation of the www.indiandentalacademy.com upper first molar behind an uprighted distally rotated lower molar.
JCO 1977; 11(10): 661-682
#9 Unlocking the malocclusion in a progressive sequence of treatment in order to establish or restore more normal function. Bio-Progressive Therapy maintains that many malocclusions have resulted because of abnormal function, and that the present malocclusion, while stable under its present abnormal function, may never have had the opportunity for normal development. Planning for the unlocking of the malocclusion begins at the initial exam and evaluation. 1. To describe the malocclusion and visualize the position of the teeth in terms of what functional influences have been responsible for their present alignment. 2. To describe the facial type and skeletal structure from the cephalometric xrays, and the implied description of function. 3. To describe the present abnormal functional influences upon the dental arches; if not abnormal, then lack of normal development by default. www.indiandentalacademy.com
JCO 1977; 11(10): 661-682
The following process of evaluation is used in setting up a treatment plan and prescribing the various appliances and treatment: I. Functional influences and their correction. II. Orthopedic alterations that may be necessary. III. Arch form— arch length, extraction needs. IV. Tooth movements and anchorage planning. V. Case management, with key factors to monitor during treatment. Situations where treatment changes alter the environment, which then allow an improved function to support it. 1. Upper Arch Expansion. 2. Incisor Protrusion Correction. 3. Temperomandibular Joint Dysfunction. Further restriction of a collapsed upper arch can develop into a functional crossbite where occlusal interference now blocks upper arch development and produces condylar shifts and changes in the temporomandibular joint function and development www.indiandentalacademy.com
JCO 1977; 11(10): 661-682
#10 Efficiency in treatment with quality results utilizing a concept of prefabrication of appliances. In an attempt to relieve some of the burden imposed by the myriad of procedures that are required in the construction and fabrication of orthodontic appliances, Bio-Progressive Therapy utilizes the concept of prefabrication and has appliances readymade for clinical application, so that the clinician directs his expertise to diagnosis and treatment planning.
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JCO 1977; 11(10): 661-682
THE VISUAL TREATMENT OBJECTIVE It is a visual plan to forecast the normal growth of the patient and the anticipated influences of treatment, to establish the individuals objectives we want to achieve for that patient. CONSTRUCTION OF THE VTO The VTO construction is divided into the following steps: I. The cranial base prediction II. The mandibular growth prediction III. The maxillary growth prediction IV. The occlusal plane position V. The location of the dentition VI. The soft tissue of the face www.indiandentalacademy.com
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ORIGINAL TRACING
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I. VTO — Cranial Base Prediction
Grow Nasion 1mm/year (average normal growth) for 2 years (estimated treatment time). Grow Basion 1mm/year (average normal growth) for 2 years (estimated treatment time).
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II.VTO — Mandibular Growth Prediction
Rotation Condylar Axis Growth & Corpus Axis Growth Symphysis Construction
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II.VTO — Mandibular Growth Prediction — Rotation
The average such effect of mechanics on mandibular rotation is as follows: 1. Convexity Reduction— Facial Axis opens 1°/ 5mm. 2. Molar Correction — Facial Axis opens 1°/ 3mm. 3. Overbite Correction — Facial Axis opens 1°/ 4mm. 4. Crossbite Correction— Facial Axis opens 1°-1½°. Recovers half the distance 5. Facial Pattern— Facial Axis opens 1°/1 S.D. dolichofacial; 1° closing www.indiandentalacademy.com effect against mechanics if brachyfacial. JCO 1977; 11(11): 744-763
Rotate "up" at Nasion to close the bite and "down" at Nasion to open the bite using point DC as the fulcrum.
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ii. VTO — Mandibular Growth Prediction—Condylar Axis Growth & Corpus Axis Growth
1mm per year down from point DC PM moves forward 2mm/year
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ii. VTO — Mandibular Growth Prediction — Symphysis Construction
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III. VTO — Maxillary Growth Prediction
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iii. VTO — Maxillary Growth Prediction — Point A Change Related to BA-NA Mechanics
Maximum range
1. HG
-8 mm
2. Class II elastics
-3 mm
3. Activator
-2 mm
4. Class III elastics
+2-3 mm
5. Face Mask
+2-4 mm
For every 1mm distal movement of Point A there is a downward movement of 0.5mm
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IV. VTO — Occlusal Plane Position
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V. VTO — Dentition — Lower Incisor
For each 1mm of forward compromise the angle increases by 2°
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v. VTO — Dentition — Lower Molar
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V. VTO — Dentition — Upper Molar
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V. VTO — Dentition — Upper Incisor
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VI. VTO — Soft Tissue — Nose
www.indiandentalacademy.com Move 1mm back for every year along palatal plane JCO 1977; 11(11): 744-763
VI. VTO — Soft Tissue — Point A and Upper Lip
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VI. VTO — Soft Tissue — Lower Lip, Point B,
Mid points of overjet and overbite
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VI. VTO — Soft Tissue — Chin
Soft tissue chin is evenly distributed taking into consideration reduction of strain and bite opening www.indiandentalacademy.com JCO 1977; 11(11): 744-763
VTO — Completed Visual Treatment Objective
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JCO 1977; 11(11): 744-763
USE OF SUPERIMPOSITION AREAS TO ESTABLISH TREATMENT DESIGN It is necessary to understand the following to draw up an effective treatment plan. 1. Describe the basic facial, skeletal and dental structures 2. Understand the anticipated normal growth in amount and direction in various areas of the face and jaws. 3. Understand the response of individual skeletal and facial structures to various treatment mechanics. Eleven factors of the basic facial and skeletal structures are recorded from the cephalometric tracing to describe the chin, maxilla teeth and soft tissue profile. Five areas of superimposition within which seven areas of evaluation are used to evaluate. www.indiandentalacademy.com
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THE ELEVEN FACTOR SUMMARY ANALYSIS
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DESCRIBING THE FACE
1. Facial Axis Angle: Gives the direction of growth of the chin and expresses the ratio of facial height to the facial depth
2. Facial Angle: This locates the chin horizontally in the face. It is a facial depth indicator; and it determines if a skeletal Class II or Class III is due to the mandible. www.indiandentalacademy.com
3. Mandibular Plane Angle: A high mandibular plane angle implies that a skeletal open bite is due to the mandible. A low mandibular plane angle implies that a skeletal deep bite is due to the mandible.
Lower face height describes the divergence of the oral cavity
Mandibular arc describes the mandible and tells us the direction of growth of the mandible Lower Face Height
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Mandibular Arc
Superimposition Area 1 (Evaluation Area 1) (Basion-Nasion at CC Point)
Evaluate the amount of growth of the chin in millimeters; Any change in chin in an opening or closing direction that may result from our www.indiandentalacademy.com mechanics; Any change in upper molar. JCO 1977; 11(12): 820-834
Superimposition Area 2 (Evaluation Area 2) (Basion-Nasion at Nasion)
ď‚ŻTo show any change in the maxilla (Point A). ď‚ŻWith Evaluation Area 2, we determine whether we wish to use an orthodontic www.indiandentalacademy.com or an orthopedic force on the maxilla with a headgear. JCO 1977; 11(12): 820-834
Superimposition Area 3 (Evaluation Areas 3 and 4) (Corpus Axis at PM)
ď‚ŻIn Evaluation Area 3, we evaluate whether we are going to intrude, extrude, advance or retract the lower incisors, which helps us determine what type of utility arch we will use. ď‚ŻIn Evaluation Area 4, we evaluate the lower molars to determine what type of anchorage we need and whether www.indiandentalacademy.com we wish to advance, upright or hold the lower molars. JCO 1977; 11(12): 820-834
Superimposition Area 4 (Evaluation Areas 5 and 6) (Palate at ANS)
In Evaluation Area 5, we evaluate what we are going to do with the upper molars — hold, intrude, extrude, distallize or bring them forward. In Evaluation Area 6, we evaluate what we are going to do with the upper www.indiandentalacademy.com incisors— intrude, extrude, retract, advance, torque or tip them. JCO 1977; 11(12): 820-834
5th Superimposition Area (Evaluation Area 7) (Esthetic plane at the crossing of the occlusal plane)
ď‚ŻEvaluate the soft tissue profile. ď‚ŻIn normal growth, the face becomes less protrusive with reference to the esthetic www.indiandentalacademy.com plane. JCO 1977; 11(12): 820-834
ORTHOPEDICS IN BIOPROGRESSIVE THERAPY By definition orthopedics implies any manipulation that alters the skeletal system and associated motor organs. From a practical standpoint in a growing individual orthopedic alteration would be any manipulation which would change the normal growth of the dentofacial complex in either direction or amount. It is important to describe the basic facial and dental characteristics of the classical orthopedic problem. Bimler described Class II skeletal malocclusion as Micro Rhino Dysplasia
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MICRO RHINO DYSPLASIA
1. Upward tilt of the palate 2. Short Vertical height of the nose 3. Upward cant of the nares 4. High convexity (+6mm or more) 5. Excessive anterior overjet 6. Finger, tongue or lip habits 7. Hypertonic lower lip 8. Retruded Lower Arch 9. Fractured Upper Incisors 10. Hypotonic Upper Lip 11. Blocked Upper Laterals and Canines 12. Mandible apparently unrelated
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(A) protrusion and tapering of the anterior arch form that quite often blocks eruption of the upper lateral incisors. The upper cuspid width (B) is narrow and confined by the caninus muscle. Arch widths across the upper bicuspids (C) and upper molars (D) are also narrow in response to their mesial position over the lower arch. The upper molars (E) are in mesial rotation. The lower bicuspids (F) are quite often lingually inclined The anterior mandibular arch form is flattened (G) with the lower incisors positioned lingual to the lower canines.
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JCO 1978; 12(1): 48-69
CLASSICAL RESPONSES WITH DIFFERENTIAL HEADGEAR THERAPY Generalized Orthopedic Response With Cervical Headgear Alone The general orthopedic response in the mandible is highly variable, depending upon facial growth type, the maxillae invariably respond in a highly predictable way to a line of force directed at the level of, or below, the rotational center of the maxillae. At a point which roughly approximates the top of the pterygomaxillary fissure, the maxillary complex rotates in a clockwise direction This rotational effect accounts for the reduction in maxillary protrusion, a downward canting of the palatal plane and concomitant nasal changes www.indiandentalacademy.com
JCO 1978; 12(1): 48-69
Generalized Orthodontic Response With Cervical Headgear Alone Extrusion of the upper molars occur, the effect of which is primarily dictated by the facial growth pattern. The upper incisor will tip lingually (from its apex) - after overjet has been reduced enough to allow the everted lower lip to close over the upper incisor The lower molars upright and often move distally when carried by the incline planes of the extruded upper molar. The lower incisor, without the inhibiting effect of the lower lip, will quite often tip labially as the upper and lower lips start to reach equilibrium, and the tongue starts to dominate the labial positioning of these teeth. www.indiandentalacademy.com
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ď‚ŻThe net effect is that in weak muscular growth patterns the extrusive effects of cervical headgear are elicited as a negative response in the mandible (orthopedic in nature) ď‚ŻIn strong muscular patterns the extrusive forces of the cervical headgear are seen as responses in the dentition (orthodontic in nature)
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REVERSE RESPONSE
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Expansive Responses With Headgears From the mechanical standpoint a progressive widening and tipping of the alveolar base is accomplished by a widening of the inner bow of the face bow. This expansive process provides for several distinct considerations: 1. Reciprocal expansion of the lower arch. This can be observed as an anterior movement of the lower incisor and in the horizontal plane increases in arch width occur. 2. Preventing impacted second molars. When the upper first molar is translated distally without expansion, the incline planes of that tooth start to reciprocally constrict the lower molars, carrying them to the lingual. This tends to either impact the lower second molar or force them buccally.
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Soft Tissue Esthetic Changes
ď‚ŻWith normal growth (left), the soft tissue nose is seen to grow concentrically approximately 1 mm per year at the tip. The cant of the nares remains unchanged. ď‚ŻFollowing headgear therapy (right), the nose is seen to cross over at the bridge, lengthen vertically, and the upward cant to the nares is tipped down to a more horizontal position.
A
B
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Generalized Response With Combination Type Headgears In dolichofacial patterns, it often is desirable to create a rotational orthopedic effect in the maxillae and at the same time maintain mandibular stability. Long-term directional headgear therapy (part time wear), where the force is applied below the center of resistance of the maxillae, again allows the classical orthopedic response, but without the upper molar extrusion. If the force applied moves the maxillae distally without overriding musculature, and is in conjunction with mandibular growth, the lower face height can be closed or maintained while achieving a reduction of the maxillary protrusion.
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Force Direction
Forces applied to the maxillae through the face bow are either a. Restrictive (retard downward and forward growth) (A) b. Rotational (B) a. Restrictive forces occur when the vectoral sum of forces lies above the centre of resistance of the maxillae b. Rotational forces occur when the vectoral sum of forces lie below the centre of the resistance of the maxillae. www.indiandentalacademy.com
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Mechanical Application of The Cervical Headgear 1. Force Level - A force level above 400 grams is ideal. In most patients, forces up to 1000 grams can easily be tolerated and should be applied when possible. 2. Intermittent Wear (a) sclerotic condition of molar roots- orthopedic effect (b) Rebound (c) Patient acceptability is enhanced 3. Outer Bow Length and Position A rigid outer bow extending beyond the molars and tipped up 15째 to the ala of the ear will prevent propping open the bite by excessive tipping at the molars and will maximize orthopedic effect by pitting the roots against cortical bone. 4. Expansion-Rotation It is essential to continually expand the inner bow of the cervical headgear, not only to correct the tendency to crossbite but also to allow a functional development of the lower arch. 5. Freedom of Movement of the Maxillae www.indiandentalacademy.com
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Factors Causing Excessive Mandibular Rotation 1. Weak Muscular Pattern 2. Not Retarding Effective Eruption of The Lower Molars Retarding the normal upward forward development of the lower molar will have a tendency to counteract the overall rotational effect on the mandible. 3. Severe Tipping of Upper Molars Maintaining a slight upward cant to the outer bow will minimize this tipping effect. Severe tipping also is seen in those cases where effective growth has been completed. 4. Full Arch Therapy Without Freeing Anterior Occlusion— Incisal Trauma 5. Fulltime Cervical Headgear Therapy
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UTILITY AND SECTIONAL ARCHES The most recognizable single entity in BPT is the utility arch. It forms the base unit around which the mechanics in all types of cases can be employed.
Historical Perspective and Development of the Utility Arch
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Construction specifications of the mandibular utility arch The mandibular utility arch is best fabricated from 0.016” x 0.016” blue elgiloy wire in order to create a force system that delivers a continuous force that is light enough to be in the range of 50-75 gms. Design Principle The principle of the long lever arm, from the molars to the incisors is applied to deliver a light continuous force. The utility arch is stepped down to avoid interference from the forces of occlusion. The buccal bridge section is flared bucally to prevent tissue irritation, opposite the vertical steps as the arch approaches the tissue and as the incisor teeth are intruded. www.indiandentalacademy.com
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Fabrication of the Mandibular Utility Arch 1) Vertical Step Height In the lower arch it is 3-5mm The only function of the vertical step is to bring the malleable 0.016 x 0.016 elgiloy wire out of the occlusion to avoid deformation with functional movements. It is usually formed with a hoe plier. The anterior vertical step should be extended far enough beyond the lateral incisor brackets (2-3 mm_ to allow unraveling and alignment of the incisors. 2) Placement of Labial Root Torque. When the wire is bent at the anterior vertical step 10° - 15° of lanial root torque is incorporated. The anterior arch form is then contoured using a small turret/arch forming plier. www.indiandentalacademy.com JCO 1978; 12(3): 192-207
3) Finishing the Opposite Side. The same procedure is continued in reverse order after lacing into anterior brackets. 5) Activation of the Distal Legs. The molar section that extends into the molar tube has a 45° buccal root torque, 30°-45° distal lingual rotation with a 30°-45° tip back bend. Molar uprighting and incisor intrusion 6) Final Arch Form and Activation Characteristics. The precisely contoured anterior arch form will allow the incisors to intrude without advancing. 5°-10° labial root torque will counteract the forward tipping action and allow the incisor roots to avoid cortical bone. The posterior legs are parallel to each other and 45° buccal root torque has been placed to maintain the buccal cortical support in the lower molar region.www.indiandentalacademy.com JCO 1978; 12(3): 192-207
COMPLETED MANDIBULAR UTILITY ARCH
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Placement of the mandibular utility arch
When the lower utility arch is engaged In the lower Incisors, approximately 50 to 75 grams (A) of Intrusive force should be applied. Slight labial root torque (5° to 10°) allows the lower Incisor to avoid cortical bone in its intrusive movement (B). www.indiandentalacademy.com
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INTRA ORAL ADJUSTMENTS
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JCO 1978; 12(3): 192-207
Roles and Functions of the lower utility arch A. Position of the lower arch to allow for cortical anchorage In their normal eruptive positions, the lower molars do not need to be moved bucally or torqued bucally to put them in their ideal anchorage positions. Distal uprighting of the molars is done to enhance anchorage. Torquing of the molar roots bucally under the oblique ridge of the cortical bone.
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B. Manipulation and alignment of the lower incisor segment Intrusion/extrusion of the incisors to the level of the buccal functioning occlusion Advancement/retraction of the incisors in either expansion or non expansion cases. Leveling and rotational control of the individual incisor teeth. Axial inclinational control by labial or lingual crown torque. C. Stabilization of the lower arch allowing segmental treatment of the buccal segment Acts to maintain arch stability while canines are intruded and positioned separately. Allows use of segmented arch mechanics with cuspid retraction against anchorage of all other teeth. Stabilizes the lower arch for Class II elastics to upper segmented or utility arches. Allows rotation and alignment of the teeth in the buccal segment. D. Physiological roles of the lower utility arch Buccal arm acts as a cheek bumper causing expansion of the buccal occlusion. Allow better buccal teeth eruption by removing functional interferences. Corrects overbite before overjet thus avoiding incisor interference Maintains the physiologic arch www.indiandentalacademy.com form and/ or molar width. JCO 1978; 12(3): 192-207
E. Over treatment Allows end to end incisor relationship as over treatment in deep bite cases. Over treatment of buccal occlusion and cuspid relationships via segmented arch treatment. Over treatment of rotations in buccal occlusion F. Role in mixed Dentition Incisor and molar control during transitional stage of buccal dentition. Allows distal eruption of the lower second bicuspid when deciduous molars are uprighted. Rotational correction of the bicuspids and cuspids during eruption. G. Arch length control 1. Uprighting the lower molars: using the tip back bend of the utility arch uprighting of the molar results in a 2mm gain of the arch length on each side along with leveling of the curve of Spee. 2. Advancement of the lower incisors when lingually placed: Steiner’s rule would dictate that for each 1mm that the lower incisors are brought forward 2mm of arch length is gained. 3. Expansion in the buccal segment: Ricketts rule dictates that for each 1mm of expansion across the bicuspids or deciduous molars, ½ mm of arch length is gained and for each 1 mm of expansion across the molars 1/3 mm of arch length is gained. www.indiandentalacademy.com 4. Saving E space: Space gained when the lower deciduous molars are lost. JCO 1978; 12(3): 192-207
MODIFICATIONS OF THE MANDIBULAR UTILITY ARCH
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JCO 1978; 12(3): 192-207
BIOPROGRESSIVE MIXED DENTITION TREATMENT BPT in the mixed dentition aims at the natural tendency to alleviate the problem when it is noticed and the somewhat overstated concept of “interception versus correction�.
Objectives of early treatment I.
Resolve Functional Problems: The practical definition of a functional problem is anything that disturbs the growth, health and function of the temperomandibular joint complex.
II.
Resolve arch length discrepancy: so that those cases within the bounds of non extraction therapy can be approached in a manner that allows for their successful conclusion without removal of permanent teeth.
III. Correct Vertical Problems: IV. Correct Overjet Problems: www.indiandentalacademy.com
JCO 1978; 12(4): 279-298
GROWTH CONCEPTS ď‚Ż The wide variety of the research involving the growth of the condyle and the mandible the following conclusions may be derived: 1. Cases with stronger mandibular growth turgor have a propensity for upward/forward growth of the condyle. 2. Cases with a weak growth turgor demonstrate a more upward/backward growth of the condyle 3. Morphology alone suggests that the upward/forward cant or bend of the condyle and neck in brachyfacial types and the upward/backward cant and bend of the condyle and neck in dolicofacial types delineates ultimate vertical growth and forward posture of the chin in the face. ď‚Ż Anything which jeopardizes the normal upward and forward growth of the condyle resulting in a temperomandibular joint dysfunction is worthy of intervening treatment, this forms the basis of treatment in the mixed dentition. www.indiandentalacademy.com JCO 1978; 12(4): 279-298
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JCO 1955; AJO 1978; June 12(4): 279-298
I. RESOLVE FUNCTIONAL PROBLEMS Nine general categories of functional problems can be detected by clinical or roentgenographic examination of the patient at an early age: 1. Cross-mouth interferences 2. Anterior cross bite 3. Open bite- Lack of incisal guidance 4. Excessive range of function 5. Distal Displacement 6. Loss of posterior support – Superior displacement 7. Finger Sucking/ Lip sucking/ Tongue thrusting 8. Breathing and Airway problems 9. True Class III Growth patterns
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JCO 1978; 12(4): 279-298
1. Cross- mouth interferences A. Clinical Evaluation: Cases where one or more teeth cause shunting of the mandible in a lateral direction upon final closure. Typically there will be a lateral shunt a ‘comfort occlusion�, or a broad arc of closure toward one side or the other. In the wide open posture usually the midline will align at wide open, and upon closure there will be a midline shift as guided by neuro- muscular reflexes.
B. Laminagraphic Evaluation: The condyle is typically brought down on the eminence on one side and is either ideally seated or distally positioned on the opposite side. The opposite side from the shift acts in a translatory manner while the shifting side condyle is brought into apposition with the greatest height of the eminence. www.indiandentalacademy.com JCO 1978; 12(4): 279-298
C. Resultant growth changes: The translatory condyle may remain normal in growth but the opposite side condyle will commonly demonstrate restricted growth on its anterosuperior surface and increased growth in the posterosuperior surface will ensue. Long term growth effects will demonstrate •a cant in the occlusal plane, •abnormal ramal heights, abnormal alveolar process heights, •abnormal chin positioning. D. Timing and method of treatment: Cross mouth interference should be removed as soon as it is noted. In deciduous dentition, this may mean an equilibration of a posterior tooth, or canine, to alleviate the shunting. If the problem is due to bilateral constriction of the maxillae, expansion therapy is indicated usually when the upper first molars have erupted sufficiently to allow placement of the expansion appliance. www.indiandentalacademy.com
JCO 1978; 12(4): 279-298
2. Anterior crossbite A. Clinical evaluation: When one or more anterior teeth are severely malposed, the mandible may be guided forward by the anterior interference. Clinically, when the mandible is nudged gently in a distal direction and closed, the area of anterior interference can easily be detected. It is not uncommon to experience anterior displacement in cases with extreme crowding and/or situations of ectopic eruption of incisors.
B. Laminagraphic evaluation: When anterior mandibular shunting occurs, often both condyles are brought down toward the apex of the eminence (i.e., out of the fossae) and, quite commonly, articular space superior and posterior to the condyles is evidenced. www.indiandentalacademy.com
JCO 1978; 12(4): 279-298
C. Resultant growth changes: As both condyles have been brought down on the eminence, upward-backward growth of the condyles is bilaterally enhanced. This can increase effective mandibular length and is believed to be a contributing factor in Class III malocclusion. D. Timing and method of treatment: It should be determined whether the individual case is a true Class III malocclusion or simply an anterior interference. When the case is simply an anterior interference, alignment of one or more teeth to prevent the interference is ideal. This is most easily accomplished prior to full eruption of the incisors or before incisal trauma damages the teeth at the site of interference.
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JCO 1978; 12(4): 279-298
3. Open bite— Lack of incisal guidance A. Clinical evaluation: During active eruptive phases, all cases at one point or another exhibit either anterior or posterior open bite. Once the eruptive process of the upper and lower incisors has been abbreviated (usually by contact with the soft tissue lip or tongue) and active eruption no longer exists, lack of proprioceptive guidance from the anterior teeth to position the condyles in the fossae allows for excessive mobility of the mandible. Clinically, these patients commonly show difficulty in finding centric occlusion. There is generally a forward shunt of the mandible (to reach out for incisal proprioception) and quite commonly the mandible can be manipulated distally by extending the thumb from the lower incisors to the upper incisor teeth. B. Laminagraphic evaluation: The condyles are usually forward in the fossae, down on the eminence, and often there is flattening and irregularity of the antero-superior surfaces of the condyles. www.indiandentalacademy.com
JCO 1978; 12(4): 279-298
C. Resultant growth changes: Loss of guidance of the condyle in the fossa causes abrasion or wear due to the excessive anteroposterior slide. This can result in growth at the apex of the condyle and increase upward/backward growth. D. Timing and method of treatment: This is certainly the most difficult of all functional problems to correct early, as the etiologies of open bite are multiple. At this point, there are several basic areas to explore in early correction of open bite: 1) Evaluate airway for possible tonsillectomy and/or adenoidectomy; 2) Orthopedically expand and rotate the maxillae to improve tongue space, increase vertical height to the nasal complex, and change inclination of the maxillae, especially in severe Class II malocclusions; 3)Evaluate allergy symptoms; 4) Early alleviation of severe anterior crowding to allow normal incisor eruption; 5) Evaluate tongue size, posture, and tongue thrusting pattern.
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JCO 1978; 12(4): 279-298
4. Excessive range of function A. Clinical evaluation: Extreme maxillary prognathism causes the mandible to "reach" forward in order to create a "comfort" centric occlusion. These cases are referred to as "super Class II" malocclusions, as the mandible must reach forward to gain even a Class II molar relationship. Clinically, severe Class II malocclusion in which the mandible can be nudged gently back into centric relation and, upon closure, shows a more severe maxillomandibular dental relationship, is evidence of abnormal range of function. B. Laminagraphic evaluation: Upon centric occlusion, the condyles will be forward in the fossa, downward and forward on the eminence, and will quite often reveal flattening of the anterosuperior surface of the condyle. Excessive joint space superior and distal to the condyles will be evidenced and, frequently, an upward/backward bend to the neck and the condyles will be seen. www.indiandentalacademy.com JCO 1978; 12(4): 279-298
C. Resultant growth changes: Pressure atrophy and sclerotic changes at the antero-superior surface of the condyles enhances the upward/backward growth and produces a more dolicofacial type of growth experience. D. Timing and method of treatment: Although it is not critical that the entire Class II malocclusion be corrected, it is important that the maxillae and/or teeth be moved distally enough to allow the mandible to close without bringing the condyles downward and forward on the eminence. It is not unusual, following initial headgear therapy, to be able to cephalometrically measure a distal movement of the maxillae without appreciable correction of the Class II molar relation. This can be the result of a distal movement of the mandible, as the condyles drop back into the fossae. This may be the most important functional change which occurs with headgear therapy.
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JCO 1978; 12(4): 279-298
5. Distal displacement A. Clinical evaluation: The true distal displacement, in which the condyle is located in the posterior aspect of the temporomandibular joint, is quite commonly caused by a vertical inclination of the upper and lower incisor teeth, especially evidenced in Class II Division II malocclusion. Although it is possible for distal displacement to exist due to the inclines of the functioning buccal occlusion, incisal interferences are usually the culprits. These are typically the first functional problems to demonstrate pain in the temporomandibular joint complex and it is possible to have crepitation, tinnitus, and early loss of mobility in a relatively young child. B. Laminagraphic evaluation: The
condyles are seated distally in the fossae with excessive space anterior and superior to the condyles. The posterior portion of the condyles is often seen to abut the tympanic plates and petrotympanic fissure of the temporal bone. Usually no irregularities in the condyles are www.indiandentalacademy.com evidenced.
JCO 1978; 12(4): 279-298
C. Resultant growth changes: Since there is no interference with the antero-superior portion of the condyles, these cases most often demonstrate normal growth turgor in the condyles. It is felt by some that it is the lack of normal articulatory pressure at the anterosuperior portions of the condyles that enhances the brachyfacial aspect of these particular cases. D. Timing of treatment: As the distal displacement is often caused by the vertical eruptive pattern of the upper and lower incisors, clinical factors which cause this eruptive pose should be avoided. Early removal of deciduous cuspids in the deep bite, brachyfacial type cases will free the anterior teeth to move in a lingual direction. This will further deepen the bite and the incisal trauma will slowly seat the condyles distally in the fossae. When a vertical inclination of the incisors already exists, early advancement of the upper incisors to create overjet often will allow the protracting musculature of the mandible to react, dominate, and free the condyles of the distal displacement. Over closure of the mandible, with excessive freeway space, will also allow the condyle to seat distally in the fossa. Long-term, gentle, Class II elastics which help protract the mandible, as well as allow extrusion of the posterior buccal segments, are most helpful in correction of distal displacement. Where the extreme brachyfacial type exists, avoidance of extraction is important to assure proper vertical support in the buccal segment. www.indiandentalacademy.com
JCO 1978; 12(4): 279-298
6. Loss of posterior support superior displacement A. Clinical evaluation: a superior and distal movement of the condyles, as in distal displacements, can have an early onset of pain. Although this functional problem is seldom seen in the mixed dentition, ankylosis of numerous deciduous teeth and/or numerous congenitally missing teeth can create superior displacement. Superior displacement is most commonly seen, however, in the adult patient where anterior teeth have been retained, posterior teeth have been extracted, and proper vertical support in the buccal segments has not been maintained. Superior displacements are also seen in open bite cases where only a posterior occlusion exists. The condyles are seated superiorly in the fossae as the mandible pivots off of the limited posterior contacts. B. Laminagraphic evaluation: The superior portion of the condyles seat near the apex of the fossae and excessive space is seen mesial to the condyle. www.indiandentalacademy.com
JCO 1978; 12(4): 279-298
C. Resultant growth changes: As in the posterior displacements, there do not appear to be any early signs of growth alteration due to superior displacement. D. Timing and method of treatment: Since the superior displacement can be caused by loss of posterior support, early removal of carious deciduous teeth without proper vertical support can be influential in creating this abnormal position to the condyles. When a stronger muscular pattern exists, and numerous deciduous teeth must, by necessity, be removed, replacement of these teeth in a retainer is important. The over closure syndrome can take some time to develop and it is quite difficult to restore once the posterior vertical dimension has been diminished and the retained anterior teeth have adapted to the abnormal positions of the condyles.
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JCO 1978; 12(4): 279-298
7. Finger sucking /Lip sucking/Tongue thrust A. Clinical evaluation: An open bite syndrome that is commonly initiated by the finger, aggravated by the lip, and maintained by the tongue can be considered a functional problem in that these habits may cause the development of, or accentuate, an open bite. It is not unusual for youngsters to suck on digits up to five or six years of age. However, when the permanent incisors start to erupt, deformation of the anterior alveolar process with dental protrusion and open bite can occur. Once the open bite occurs, the tongue and lip oppose during the act of swallowing, aggravating and continuing the open bite pattern. B. Timing and method of treatment: The approach toward the functional muscular problem should begin as a conservative suggestion to the child that the activity should be ceased. If the child is unable to control the habit pattern, expansion/thumb appliances should be placed when the upper and lower incisors and first molars are erupting. Due to the fact that these habit problems often cause constriction and posterior crossbite, expansion appliances should be incorporated at the same time the digit habit is being alleviated. www.indiandentalacademy.com
JCO 1978; 12(4): 279-298
8. Breathing and airway problems A. Resultant growth changes: Because the tongue is held low in the oral cavity to increase air uptake, these cases are prone to maxillary collapse and crossbite. While holding the tongue low and the mouth open, the condyles are cantilevered down on the eminence, allowing the suprahyoid musculature to dominate, holding the chin down and back. This action creates wear on the upward/forward portion of the condyle and, again, allows upward/backward growth to dominate. Dominant upward/backward growth allows for a more receded chin posture in the face, worsening the open bite, and accentuating the functional muscular aberration. B. Timing and method of treatment: Although the oral and nasal passages increase in size as the child grows, and tonsils and adenoids atrophy with age, long-term breathing problems that create open bite and potentially affect condylar growth, should be evaluated at an early age. It is not unusual to suggest tonsillectomy and/or adenoidectomy, allergy evaluation, and early orthodontic therapy to increase the size of the nasal airway.
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JCO 1978; 12(4): 279-298
9. True Class III Growth Patterns A. Clinical evaluation: True Class III growth patterns represent the epitome in functional problems. They quite often exhibit a genetic propensity for extreme upward/backward condylar growth, increasing the overall effective length of the mandible. This, in conjunction with maxillary deficiency, can be mistaken for the simple anterior crossbite or vice versa. When true Class III is suspected, a family history as well as early cephalometric evaluation is warranted. Several cephalometric measurements can be utilized to evaluate the possibility that a Class III growth pattern exists. B. Laminagraphic evaluation: When the mandibular teeth have bypassed the maxillary incisors, the condyles are often downward and forward on the eminence, with excessive space superior and distal to the condyles in the fossae. A long, thin condylar neck and long, thin ramus is often noted. Where the lower incisors are locked beneath the upper incisors or the patient physically restrains the mandible, distal displacement may be noted www.indiandentalacademy.com in the true Class III.
JCO 1978; 12(4): 279-298
C. Resultant growth changes: The true Class III has an inherent tendency for functional displacement and genetic overgrowth. D. Timing and method of treatment: When the true Class III growth pattern is detected early, it is usual to treat only the maxillary deficiency. Quite often early dental treatment of true Class III results in linguoversion of the lower incisors and proversion of the upper incisors, which can make successful surgery at a later time difficult without retreatment. Relatively few true Class III's lend themselves to purely orthodontic treatment alone. Maxillary expansion and advancement, in an attempt to reduce maxillary deficiency, is the usual treatment of choice.
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JCO 1978; 12(4): 279-298
II. Resolve Arch Length Discrepancy
Arch length gain in the lower arch occurs three ways.
1. Lateral expansion of the lower buccal segments A. Expansion primarily by change in axial inclination B. Expansion by midpalatal disjunction
2. Advancement or forward movement of the lower incisors
3. Uprighting and/or distal movement of the lower molars
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JCO 1978; 12(4): 279-298
1. Lateral expansion of the lower buccal segments Many cases, especially those of a Class II nature, demonstrate the possibility for arch length gain by lateral expansion of the lower buccal segments. This is a functional type of expansion, which proceeds in a slow, meticulous manner. As the upper arch is expanded and moved distally (and held in its expanded form for a long period of time), the lower arch responds, through muscular adaptation and function, reciprocally to expand.
Lingual tipping of upper molar (above) must be distinguished from true maxillary deficiency (below).
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JCO 1978; 12(4): 279-298
A. Expansion primarily by change in axial inclination The appliance used to change arch form in most cases is the quad-helix or W expansion appliance (Ricketts). Following expansion with the W appliance the following should occur, The upper molars should be rotated distally The upper buccal segments expanded, A more normal upper arch form created Increased space for erupting upper central and lateral incisor teeth. On frontal head film some midpalatal disjunction will also be noted. B. Expansion by midpalatal disjunction Where the axial inclination of the upper buccal segments is more ideal and yet crossbite exists, palatally borne appliances are typically used to enhance midpalatal disjunction. A Haas-type or modified Nance appliance is used to www.indiandentalacademy.com gain these changes. JCO 1978; 12(4): 279-298
2. Advancement or forward movement of the lower incisors When the visual treatment objectives and physiologic factors warrant (i.e., symphysis size, shape, and form; muscle position; esthetic considerations), retruded lower incisors can be gently intruded and advanced to reach a more favorable esthetic relationship to the APo line. This type of forward movement of the lower incisors is attempted in the brachyfacial type case, where bite opening should partially occur by virtue of incisor intrusion, as well as change in axial inclination of these teeth. Each 1mm of forward movement of the lower incisors will yield 2mm of arch length gain (Steiner).
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JCO 1978; 12(4): 279-298
3. Uprighting and/or distal movement of the lower molars With routine use of the utility arch in deep bite situations, the simple uprighting of the lower molars will allow the roots of these teeth to come forward while yielding space in the arch. When mesial tipping of the lower molars is evident, 2mm per side of arch length is gained by this simple uprighting effect. Further distal movement or intrusion of the lower molars can create problems with the erupting second molars. It is usually ideal to stabilize the lower molar once it has reached a normal position upright at 5° to the occlusal plane.
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JCO 1978; 12(4): 279-298
RETENTION PROCEDURES The retainer that is most commonly used after first phase therapy is the Hawley retainer with an inclined plane. The Hawley bow acts to hold upper incisor alignment and position, while the inclined plane holds the lower incisor alignment both from the labial (by the upper incisors) and the lingual (by the incline plane). The patients are instructed to wear the upper Hawley retainer full time during the first year after treatment and usually are instructed to wear the retainer at night time during the second and/or third year of retentionwww.indiandentalacademy.com therapy.
JCO 1978; 12(4): 279-298
THE BRACKET SYSTEM 1. Rickett’s Standard Bioprogressive With the advent of pre formed bands band material was designed and bracket angulations were considered so that ‘second order’ moves were built in by angulating the brackets. In the original design it was decided that a bracket should be angulated to 5° or not at all. This accounts for the original prescription of 5° on all canines and 5° on the lower molar tubes and brackets. In addition it was decide on 8° for the maxillary laterals. All the rest were straight on to the margin of the band leaving to the orthodontist the 1° to 4° changes in angulation of the bracket by fitting the band as required for the individual patient needs. It soon became evident that control of torque simultaneously with placement of loops was difficult so Rickett’s incorporated torque values of Jarabak and Holdaway into the brackets. Upper incisor of 22°, laterals 14° and cuspids at 7° of lingual root www.indiandentalacademy.com torque. JCO 1978; 12(8): 569-586
2. Rickett’s Full Torque Bioprogressive With the standard bioprogressive system difficulty was experienced in placing enough torque on the lower molar area, particularly in view of the need for anchorage. The same angulations of 7°, 14°, 21° were incorporated into the lower anterior segment, in addition the lower first molar had a rotation of 12°. Torque was also incorporated into the lower premolar bracket.
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JCO 1978; 12(8): 569-586
3. Rickett’s Triple Control Bioprogressive
Raised bracket bases of canines and bicuspids +7° torque on the canines Upper and lower molar offsets Second molar convertible tubes In the extraction series the torque on the second premolar was reduced to 7° to the lingual, the canine torque was 0 and the bracket was not raised to assist in the transition from the anterior to the buccal segment.
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JCO 1978; 12(8): 569-586
ARCH FORMS Factors taken into account in the research of arch forms included: Arch correlation Consideration of size Arch length Where the arch was to be measured Contact details Final determination of form at the bracket location Twelve arch forms were originally identified, which were narrowed down to nine by computer work. Studies of other normal and stable treated patients resulted in five arch forms.
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JCO 1978; 12(8): 569-586
Penta Morphic Arches 1. Narrow ovoid 2. Tapered 3. Normal ideal 4. Ovoid 5. Narrow tapered
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JCO 1978; 12(8): 569-586
MECHANICS SEQUENCE FOR EXTRACTION CASES The mechanics for extraction cases in BPT can best be organized into four general procedures that can be individually evaluated and analyzed as to the needs of the specific case.
I) Stabilization of upper and lower molar anchorage II) Retraction and uprighting of cuspids with sectional arch mechanics III) Retraction and consolidation of upper and lower incisors IV) Continuous arches for details of ideal and finishing occlusion www.indiandentalacademy.com
JCO 1978; 12(5): 334-357
I) Stabilization of the upper and lower molar anchorage.
Upper molar anchorage Maximum anchorage
Minimum anchorage
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JCO 1978; 12(5): 334-357
Lower molar anchorage
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JCO 1978; 12(5): 334-357
II) Retraction and uprighting of cuspids with sectional arch mechanics.
90° gable and 90° offset antirotation bends 100 to 150 gms of force 2-3 mm of activation www.indiandentalacademy.com
JCO 1978; 12(5): 334-357
Three dimensional cuspid control
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III. Retraction and consolidation of upper and lower incisors. Contraction utility arch
Torquing contracting utility arch
Utility arch with stepped up delta loop Utility arch with regular delta loop
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JCO 1978; 12(5): 334-357
Finishing wires
0.016 x 0.022 5/16� heavy class II elastics
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JCO 1978; 12(5): 334-357
MECHANICS SEQUENCE FOR CLASS II, DIVISION 1 CASES
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JCO 1978; 12(6): 427-439
Leveling of the Lower arch
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JCO 1978; 12(6): 427-439
Upper Buccal segment alignment
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JCO 1978; 12(6): 427-439
Class II elastics and complete lower arch alignment Segmental correction of the Class II with elastics. Pitting upper and lower arches with continuous archwire against each other has several detrimental effects. 1. Skidding effect that simply throws the lower arch forward while extruding and retracting the upper arch. 2. With a tendency for deep bite the class II elastics can bring the upper incisors back and start ‘jamming’ the lower incisors as they are retracted. 3. It is difficult to overcorrect the upper buccal segment without bringing the upper anterior teeth into lingual cross bite. www.indiandentalacademy.com
JCO 1978; 12(6): 427-439
Traction sections The tendency for the downward pull of the Class II elastics to extrude and throw the root of the canine mesially is countered by placing a small closed helix distal to the upper cuspid teeth with a gable or tipback of 30°. The anterior portion of the segment should also be rotated mesially 45° and often a horizontal closed helix is placed at the molar region to maintain or accentuate distal molar rotation. The traction section also stabilizes the upper buccal segments against the impending intrusion and torque in the upper incisors. www.indiandentalacademy.com
JCO 1978; 12(6): 427-439
Upper incisor intrusion and retraction
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JCO 1978; 12(6): 427-439
Idealization of arches and finishing details
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JCO 1978; 12(6): 427-439
MECHANICS SEQUENCE FOR CLASS II, DIVISION 2 CASES In general there are three treatment possibilities in a Class II, Division 2 malocclusion: 1. Distalizing the upper arch 2. Advancing the lower arch 3. A reciprocal movement, advancing the lower arch and the distalizing the upper arch at the same time. There are six functions necessary in treating Class II, division 2 malocclusions, which are general considerations for evaluating the mechanics sequence: I) Advancement, torque control and intrusion of the upper incisors. II) Intrusion of the lower incisors and cuspids. III) Alignment of the buccal segments and Class II correction. IV) Consolidation of the upper incisors. V) Idealizing the arches VI) Finishing. www.indiandentalacademy.com
JCO 1978; 12(7): 505-521
I) Advancement, torque control and intrusion of the upper incisors.
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JCO 1978; 12(7): 505-521
II) Intrusion of the lower incisors and cuspids.
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JCO 1978; 12(7): 505-521
III) Alignment of the buccal segments and Class II correction.
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JCO 1978; 12(7): 505-521
IV) Consolidation of the upper incisors.
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JCO 1978; 12(7): 505-521
V) Idealizing the arches and Finishing.
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JCO 1978; 12(7): 505-521
FINISHING PROCEDURES IN BIOPROGRESSIVE THERAPY Ricketts interpreted Angle's line of occlusion to include a line drawn through the contact points of the posterior teeth and slightly below them through the contact embrasures of the anteriors. The line is suggested as the line to which our brackets can be placed on the individual teeth in order to allow the cusp/marginal ridge function that our occlusal stops produce. www.indiandentalacademy.com JCO 1978; 12(8): 569-586
Concepts of Occlusion 1) Ideal occlusion, perhaps not quite ever found in Nature, represents an occlusion in which there is perfect size and fit of the individual teeth and the teeth are in ideal arch form, balance, and harmony; an occlusion in which every incline and stop is perfect and every tooth is in an ideal location within its arch and functions perfectly with its opponent teeth in the opposite arch. 2) Normal occlusion would be an untreated natural occlusion that is within an expected normal range of variation in all of the measurements thought to be critical in evaluating occlusion. The normal range of variation represents two-thirds of the population and eliminates those extremes on either end of the www.indiandentalacademy.com normal bell curve distribution. JCO 1978; 12(8): 569-586
3) Reconstructed occlusion represents those occlusions that are being restored, where the ability to critically record the various jaw movements is essential. The occlusion is designed to accommodate to the pathways of function recorded for the individual case and the teeth can be "constructed" to function properly in all movements in the specific case. 4) Orthodontic finishing occlusion is represented by the occlusion that is desired at the time of band or active appliance removal. www.indiandentalacademy.com
JCO 1978; 12(8): 569-586
Function Influences Finishing and Retention The proper location and function of the condyle in the temporomandibular joint is essential to the health and stability of the occlusion. A normal airway which effects the basic respiratory process and influences the tongue posture and function is important to the stability of the denture. Lip function and its variations have an influence upon the incisor alignment and stability. The buccal and facial musculature along with the muscles of mastication, which are reflected in the facial type as described by our cephalometrics, are also critical influences, and are considered during the original diagnostic criteria. www.indiandentalacademy.com
JCO 1978; 12(8): 569-586
Occlusal Check List in Finishing An occlusal check list including eight areas in each arch is used in establishing the ideal finishing arch configuration and individualized tooth rotation in our overtreated orthodontic finishing occlusion. The patient at this stage is seen at two-week appointments, for the adjustments are more delicate and controlled. During the final two-week adjustment the cuspid and bicuspid bands may be removed to allow closing of the band space. New bonding procedures that eliminate the interproximal band material may not require the stage of final finishing.
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JCO 1978; 12(8): 569-586
Occlusal Check list for finishing in mandibular arch 1. Arch width across second molars. 2. Distal of first molar rotated lingually until the distobuccal cusp approximates mesial sluiceway on second molar. 3. Large buccal offset at mesial of first molar. 4. Check inter-bicuspid width for necessary expansion. 5. Proper buccal arch form and contour. 6. Premolar offset to bring it in contact with distal lingual incline of upper canine (2-3mm). 7. Mesial of cuspid tucked slightly behind lateral incisor distal of the cuspid buccal. 8. Over-rotation of incisors; smooth arc
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JCO 1978; 12(8): 569-586
Occlusal Check list for finishing in maxillary arch 1. Width across first and second molars. 2. Distal rotation of first molar so that line drawn through distobuccal and mesiolingual cusps points to the mesial third of the opposite side cuspid . 3. Mesial offset (large) on molar. 4. Mesial rotation of lingual cusp of first bicuspid to seat in distal fossa of lower first bicuspid. 5. Premolar offset (2-3mm) to avoid first area of prematurity. 6. Cuspid brought into contact with lower cuspid and premolar to establish cuspid rise. 7. Lateral left labial (until retainer) to allow overtreatment of buccal segments; then tucked in. 8. Smooth arc across incisors. www.indiandentalacademy.com
JCO 1978; 12(8): 569-586
RETENTION IN BIOPROGRESSIVE THERAPY Retention in Bioprogressive Therapy is the process that sustains and guides the settling from the overtreated or orthodontic occlusion into the final functioning occlusion. It first guides these changes during the initial adjustments, and then supports the bony sutural and muscular accommodations to the changing environment. Finally, retention should consider the long range influences which involve changes created by growth, tooth eruption, and function, characterized by the different facial types.
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JCO 1978; 12(8): 569-586
The Initial Stage of Retention ď‚ŻThe initial stage of retention, perhaps the most obvious and critical, occurs during the first six weeks following the conclusion of the active phase of treatment when the appliances are removed and the teeth are "turned loose" to erupt along their normal eruptive paths into the functioning occlusion. ď‚ŻRetainers inserted at this initial phase are not designed to hold, but to assist in guiding this settling process.
Upper Arch Retainer
The adjustments in the upper retainer include relieving the lingual to: (1) close the anterior band space between the central and lateral incisors (buccal band space is closed with finishing arches), (2) allow the tucking in of the distal of the upper cuspids following their expansion and overtreatment, and (3) sustain the settling distal rotation of the upper molar as it functions with the lower www.indiandentalacademy.com rotated molar occlusion. JCO 1978; 12(8): 569-586
In the lower arch, a fixed first bicuspid retainer is placed in order to (1) maintain the cross arch bicuspid width and support the first bicuspid against the upper cuspid and bicuspid function, (2) allow the lower cuspids the freedom of adjustment against the upper occlusion, and (3) place a lingual bar against the incisal third of the lower incisors to maintain their alignment and rotational connection. The fixed lower retainer being back on the bicuspids is easily acceptable to the patient and can be maintained longer. www.indiandentalacademy.com
JCO 1978; 12(8): 569-586
The Stabilizing Stage of Retention The stabilizing stage of retention involves the ongoing phase over the first year following active treatment when the sutural adjustment, transseptal fibers, functioning occlusion and muscle physiology need to be considered in supporting the new occlusion. During this period the lower fixed retainer is kept in place and the upper retainer is worn most of the time. Following the 1st year, if the functioning occlusion remains stable, the retainer is worn only part time, during sleeping .
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JCO 1978; 12(8): 569-586
CONCLUSION This seminar attempted to present the basic tenets of the Bioprogressive Therapy. It began with a systems approach diagnosis and treatment planning and an overview of the management procedures used to implement and carry out the logic process employed in our treatment. Various treatment sequences were suggested that could be applied to a total course of therapy, rather than a cookbook technique blindly followed in every case. Orthopedic alteration, optimum orthodontic forces and combination of mechanics were suggested that would unlock the malocclusion in a progressive sequence in order to establish more normal function for optimum health and stability of the denture. Bioprogressive Therapy approaches an in-depth analysis of the basic malocclusion, the underlying morphology with its functional variations, then attempts to treat them to as normal a function and esthetic relationship as is possible for the long range health and stability of the denture. Each case is approached individually because of its individual morphology, physiology and malocclusion and the prescribed treatment www.indiandentalacademy.com sequence is selected to accomplish quality results with efficiency.
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