Scientific highlights of the month (April 2023)

SCIENTIFIC HIGHLIGHTS

Short overviews on recently published scientific evidence.

Issue 2/2023

Edited by Dr. Marcin Maj

IN THIS ISSUE

EDITOR’S CHOICE

Mandibular bone characteristics, drilling protocols, and final insertion torque for titanium-zirconium mini-implants for overdentures: A cross-sectional analysis.

(C. Rodrigues Leles et al. 2023)

and

The use of autologous bone for augmentation procedures leads to low prevalence of peri-implantitis-a retrospective study over a 20-year period

(PF Carls al. 2023)

Immediate vs. Delayed Placement of Immediately Provisionalized SelfTapping Implants: A Non-Randomized Controlled Clinical Trial with 1 Year of Follow-Up

(P. Carosi et al. 2023)

EDITOR’S CHOICE

Clin Implant Dent Relat Res. 2023 Jan 9

Mandibular bone characteristics, drilling protocols, and final insertion torque for titanium-zirconium mini-implants for overdentures: A cross-sectional analysis.

STUDY OBJECTIVES AND METHODS

The purpose of this study was to assess the final insertion torque values achieved using site-specific drilling protocols for a novel mini implant system for removable complete overdentures. Anatomical and technical factors influencing final insertion torque were recorded and analyzed. Participants were randomized to two surgical protocol groups (flapped or flapless) and all received four mini implants (Straumann® mini implant system; Straumann AG) in the anterior mandible, using a 1.6 mm needle drill and a 2.2 mm pilot drill for the implant bed site preparation. The final insertion torque was recorded as the main outcome variable during surgery.

RESULTS

• A total of 296 mini implants were placed in 74 patients (mean age = 64.1 ± 8.0; 64.9% female) using flapless (n = 37) or flapped (n = 37) surgeries.

• Mean final insertion torque was 55.8 ± 18.4 Ncm (10.5% > 35 Ncm, 48.9% between 35 and 65 Ncm, and 40.6% > 65 Ncm).

• Higher final torque values were observed for higher bone densities (bone type I > II > III, and D1-D2 > D3-D4), highly resorbed ridge forms (5-6 > 34), flapped surgeries, and male patients. However, regression models showed that the likelihood of achieving optimal insertion torque (≥35 and ≤65 Ncm) was higher for females (OR = 2.14; 95%CI = 1.14-4.01; p = 0.018), ridge forms 3-4 (OR = 2.87; 95%CI = 1.05-7.85; p = 0.040), and flapless surgeries (OR = 1.96; 95%CI = 1.09-3.51; p = 0.024).

• All implants survived and were suitable for retaining prostheses.

CONCLUSIONS

Sufficient primary stability for immediate loading was achieved for the majority of the mini implants placed. Surgical implant bed preparation should be sitespecific to achieve optimal primary stability for immediate loading while avoiding excessive insertion torque.

Adapted from C Rodrigues Leles et al., Clin Implant Dent Relat Res. 2023 Jan 9., for more info about this publication click HERE

Cláudio Rodrigues Leles, José Luiz Rodrigues Leles, Thalita Fernandes Fleury Curado, Jésio Rodrigues Silva, Lays Noleto Nascimento, Marcella Silva de Paula, Sabrina Maniewicz, Martin Schimmel, Gerald McKenna

J Craniomaxillofac Surg. 2023 Jan 31

20-year period

Peter F Carls, Marco Bernasconi, Francesco Carinci, Mark Lawrence, J Thomas Lambrecht

STUDY OBJECTIVES AND METHODS

The aim of this study was to compare the prevalence of peri-implantitis in implants inserted into pristine bone (control) to implants where autologous bone was used for grafting procedures (study). All patients who underwent implant surgery during a 20 years interval by one maxillofacial implant surgeon and received a prosthodontic rehabilitation afterwards were eligible for inclusion in the study. Periimplant bone resorption and periimplant disease were assessed. Of 421 patients 384 (91.2%) patients responded to a recall after having been treated over a 20-year period by one maxillofacial surgeon and several dentists

RESULTS

• A total of 110 patients had 239 implants in pristine bone, and 274 patients had 607 implants placed in combination with autologous bone grafting procedures.

• Mean time in function was 74 months (range 15-236 months). In all, 342 implants (34.8%) were in function for longer than 7 years. A

• total of 64 implant sites (7.6%) in 39 patients (10.2%) showed signs of peri-implant mucositis. In addition, 17 implants (2.0%) in 14 patients (3.6%) revealed signs of peri-implantitis, of which five implants were in the control group (2.09%) whereas 12 implants were in the study group (1.98%), with no statistically significant difference (p = 0.8405).

• More than half of the patients with peri-implantitis had a history of periodontitis.

• Three implants were lost due to peri-implantitis and four implants failed for other reasons, resulting in an overall success rate of 99.2% in 846 implants.

CONCLUSIONS

The results of this in-practice comparison indicate that both attachment systems represent comparable candidates for the prosthodontic retention of 2IRODs

Adapted from PF Carls et al., J Craniomaxillofac Surg. 2023 Jan 31, for more info about this publication click HERE

The use of autologous bone for augmentation procedures leads to low prevalence of peri-implantitis-a retrospective study over a

J Clin Med. 2023 Jan 6;12(2):489

Immediate vs. Delayed Placement of Immediately Provisionalized Self-Tapping Implants: A Non-Randomized Controlled Clinical Trial with 1 Year of Follow-Up

Paolo Carosi, Claudia Lorenzi, Riccardo Di Gianfilippo, Piero Papi, Andrea Laureti, Hom-Lay Wang, Claudio Arcuri

STUDY OBJECTIVES AND METHODS

his study aimed to examine the clinical and esthetic outcomes of immediately provisionalized self-tapping implants placed in extraction sockets or healed edentulous ridges one year after treatment. Sixty patients in need of a single implant-supported restoration were treated with self-tapping implants (Straumann BLX) and immediate provisionalization. The implant stability quotient (ISQ) and insertion torque were recorded intraoperatively. A total of 37 implants were placed in extraction sockets and 23 in edentulous ridges, and then all implants were immediately provisionalized.

RESULTS

• All implants achieved a high implant stability with a mean insertion torque and ISQ value of 58.1 ± 14.1 Ncm and 73.6 ± 8.1 Ncm, respectively.

• No significant differences were found between healed vs. post-extractive sockets (p = 0.716 and p = 0.875), or between flap vs. flapless approaches (p = 0.862 and p = 0.228) with regards to the insertion torque and ISQ value.

• Higher insertion torque values and ISQs were recorded for mandibular implants (maxilla vs. mandible, insertion torque: 55.30 + 11.25 Ncm vs. 62.41 + 17.01 Ncm, p = 0.057; ISQ: 72.05 + 8.27 vs. 76.08 + 7.37, p = 0.058).

• One implant did not osseointegrate, resulting in an implant survival rate of 98.3%.

• All implants achieved PES and WES scores higher than 12 at the 1-year follow-up.

CONCLUSIONS

The clinical use of newly designed self -tapping implants with immediate temporization was safe and predictable. The implants achieved a good primary stability, high implant survival rate, and favorable radiographic and esthetic outcomes, regardless of the immediate or delayed placement protocols

Adapted from P Carosi et al., J Clin Med. 2023 Jan 6;12(2):489, for more info about this publication click HERE

Periodontol 2000. 2023 Feb 6

Peri-implantitis as the consequence of errors in implant therapy

Andrea Roccuzzo, Jean-Claude Imber, Giovanni Edoardo Salvi, Mario Roccuzzo

THE OVERVIEW

This article describes the major possible factors in implant therapy that may lead to peri-implantitis. For some of these (ie, inappropriate patient selection, insufficient periodontal therapy, lack of diagnosis and management of peri-implant mucositis, erratic supportive peri-implant/periodontal therapy) there is a good level of evidence, whereas for others (ie, wrong implant placement, poor postoperative care, inadequate prosthetic reconstruction, lack of assessment and management of peri-implant soft-tissue deficiencies) there is little scientific evidence. More research is therefore needed to clearly identify the errors and/or complications possibly leading to peri-implantitis, particularly over the long term

Adapted from A. Roccuzzo et al., Periodontol 2000. 2023 Feb 6., for more info about this publication click HERE

Periodontol 2000. 2023 Jan 22

Complications and treatment errors in implant positioning in the aesthetic zone: Diagnosis and possible solutions

Stephen T Chen, Daniel Buser, Anton Sculean, Urs C Belser

THE OVERVIEW

Incorrect implant positioning can lead to functional and aesthetic compromise. Implant positioning errors can occur in three dimensions: mesiodistal, corono-apical, and orofacial. Treatment solutions to manage adverse outcomes through positioning errors require an understanding of the underlying conditions and of those factors that may have led to the error being committed in the first place. These types of complications usually occur because of human factors. If errors do occur with adverse aesthetic outcomes, they are difficult and sometimes impossible to correct. Connective tissue grafts to reverse recession defects are only feasible in defined situations. The option to remove and replace the implant may be the only recourse, provided the removal process does not further compromise the site. Error in judgment by the clinician

Adapted from ST. Chen et al., Periodontol 2000. 2023 Jan 22, for more info about this publication click HERE

Effect of systemic antiresorptive medication on the histopathological parameters of implant osseointegration in an in vivo rodent study

Kristian Kniha, Benita Hermanns-Sachweh, Stephan Christian Möhlhenrich, Florian Peters, Marius Heitzer, Philipp Winnand, Frank Hölzle, Ali Modabber

STUDY OBJECTIVES AND METHODS

The aim was to evaluate the osseointegration of zirconia and titanium implants in the rat maxilla in specimens under systemic antiresorptive therapy. After 4 weeks of systematic medication administration (either zoledronic acid or alendronic acid), 54 rats received one zirconia and one titanium implants that were immediately inserted in the rat maxilla after tooth extraction. Twelve weeks after implant placement, histopathological samples were evaluated for implant osteointegration parameters.

RESULTS

• The bone-implant-contact (BIC) ratio revealed no significant inter-group or inter-material differences.

• The distance between the implant shoulder to the bone level was significantly greater around the titanium implants of the zoledronic acid group compared to the zirconia implants of the control group (p = 0.0005).

• On average, signs of new bone formation could be detected in all groups, although often without statistical differences.

• Signs of bone necrosis were only detected around the zirconia implants of the control group (p < 0.05)

CONCLUSIONS

At the 3-month follow-up, no implant material was demonstrably better than the others in terms of osseointegration metrics under systemic antiresorptive therapy. Further studies are necessary to determine whether there are differences in the osseointegration behavior of the different materials.

Adapted from K. Kniha et al., BMC Oral Health. 2023 Feb 22;23(1):117., for more info about this publication click HERE

REFERENCES

J. Lorenz et al., Int J Oral Implantol (Berl). 2022 Nov 15;15(4):327-338 | I. Indrikson et al., J Periodontal Implant Sci . 2022 Nov 8 | H. Moaven et al., Int J Environ Res Public Health. 2022 Oct 28;19(21):14085 | P. Parvini et al., J Clin Periodontol. 2022 Oct 10 | A. Marković et al., J Oral Implantol. 2022 Oct 1;48(5):358-36 | E Bachmann et al., J Craniomaxillofac Surg. 2022 Nov;50(11):831-836 | M. Schimmel et al., Clin Oral Implants Res. 2018 Oct;29 Suppl 16:311-330 | J.G. WIttneben et al., J Esthet Restor Dent. 2022 Dec 7 | S.N. Kahn et al., Clin Oral Impl Res. 2022;33:1254–1264 | source: www.pubmed.gov | Dr Marcin Maj holds a position of Head of Global Scientific Affairs at Institute Straumann in Basel, Switzerland