Cross Bite
www.indiandentalacademy.com
INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com
www.indiandentalacademy.com
Introduction It is a term used to describe abnormal occlusion in the transeverse plane ď Ž A Cross bite represents the disturbances in the bucco palatal or labio lingual direction when brought into occlusion ď Ž
www.indiandentalacademy.com
Classification of cross bite ď Ž
A. Anterior Cross Bite 1.Single tooth 2.Segmental B . Posterior Cross Bite 1.Unilateral 2.Bilateral C. Based on the nature of bite as: 1. Skeletal 2. Dental 3. Functional cross bite
www.indiandentalacademy.com
Etiology of Cross Bite
Retained deciduous tooth Crowding and abnormal displacement of one or more teeth Presence of habits such as thumb sucking Retarded growth of maxilla in both sagital as well as vertical direction Narrow upper arch due to decreased growth stimulation in the mid palatal suture www.indiandentalacademy.com
Collapse of maxillary arch as seen in cleft palate
Sagital discrepancy of the jaws
Unilateral hypo or hyperplastic growth of any jaw www.indiandentalacademy.com
Anterior cross bite Reverse overjet is seen ď Ž - single tooth or segmental ď Ž
www.indiandentalacademy.com
Posterior Cross Bite Abnormal transverse relationship between upper and lower post teeth ď Ž Lack of co-ordination in the lateral dimension between upper and lower arches. ď Ž
www.indiandentalacademy.com
Buccal non-occlusion-Maxillary posterior occlude entirely on the buccal aspect of mandibular posteriors -Scissors Bite
ď Ž
www.indiandentalacademy.com
Skeletal Cross Bite ď Ž
It occurs as a result of mal position or malformation of the jaws
ď Ž
Generally characterized by narrow maxillary arch www.indiandentalacademy.com
Dental Cross Bite ď Ž
Results due to localized disturbances -Ectopic eruption of permanent tooth -Over retained deciduous tooth
www.indiandentalacademy.com
Functional Cross Bite Presence of occlusal interferences result in deviation of mandible during jaw closure – Unilateral Cross Bite
Habitual forward positioning of the mandible
www.indiandentalacademy.com
ď Ž
Lingual non- occlusion Maxillary posteriors occlude entirely on the lingual aspect of mandibular teeth
www.indiandentalacademy.com
Differential diagnosis between skeletal and dental cross bite - Dental origin usually exhibits abnormal buccal or lingual axial inclination - Symmetry of dental arches on diagnostic study model - Determine if there is any lateral shift of the mandible during closure
www.indiandentalacademy.com
Dentoalveolar Crossbite with good apical base width
www.indiandentalacademy.com
ď Ž
Cross Bite with deficient apical base width
www.indiandentalacademy.com
Treatment In primary dentition If the inter molar width is satisfactory - Elimination of deflective occlusal contacts If both molar and inter canine widths are narrow -Expansion of upper arch is indicated
ď Ž
www.indiandentalacademy.com
Early Mixed dentition -Anterior Cross Bite Extracting the primary teeth if there is not enough space If sufficient space is present Removable appliance is given
www.indiandentalacademy.com
ď Ž
Posterior cross bite Removable or fixed appliance
www.indiandentalacademy.com
ď Ž
Late mixed dentition Maxillary arch expansion -Skeletal: opening the mid-palatal suture -Dental : fixed or removable appliance Single tooth cross bites: cross elastics are used www.indiandentalacademy.com
www.indiandentalacademy.com Leader in continuing dental education
www.indiandentalacademy.com