» Articles » PMID: 39589499

Development and In vitro Testing of an Orthodontic Miniscrew for Use in the Mandible

Overview
Journal J Orofac Orthop
Specialty Dentistry
Date 2024 Nov 26
PMID 39589499
Authors
Affiliations
Soon will be listed here.
Abstract

Objective: Temporary anchorage devices (TADs) have been successfully used in the maxilla. However, in the mandible, lower success rates present a challenge in everyday clinical practice. A new TAD design will be presented that is intended to demonstrate optimization of the coupling structure as well as in the thread area for use in the mandible.

Methods: Three TADs were examined: (A) Aarhus® system (68.99.33 A, Medicon, Tuttlingen, Germany), (B) BENEfit® orthodontic screw (ST-33-54209; PSM Medical, Gunningen, Germany) and (C) a new design with a two-part screw thread. The TADs were inserted into artificial bone blocks after predrilling to test primary stability. To test the fracture stability, the TADs were embedded in Technovit® 4004 (Heraeus Kulzer, Wehrheim, Germany) and torsional loaded at an angle of 90° until fracture. The threshold torque values occurring were recorded digitally. The statistical evaluation was carried out using the Kruskal-Wallis test with a post hoc test according to Bonferroni (p < 0.05).

Results: The following values were measured for the insertion torque: A: 33.7 ± 3.3 Ncm; B: 57.1 ± 8.4 Ncm; C: 34.2 ± 1.4 Ncm. There were significant differences between A-B and B-C. The measured values for the fracture strength were as follows: A: 46.7 ± 3.5 Ncm; B: 64.2 ± 5.1 Ncm; C: 55.4 ± 5.1 Ncm. Significant differences were found between all groups.

Conclusion: The adapted screw design has no negative influence on primary and fracture stability. Whether the design has a positive effect on the success rates in the mandible must be clarified in further clinical studies.

References
1.
Andrucioli M, Matsumoto M, Pereira Saraiva M, Feres M, Figueiredo L, Sorgi C . Successful and failed mini-implants: microbiological evaluation and quantification of bacterial endotoxin. J Appl Oral Sci. 2018; 26:e20170631. PMC: 6025887. DOI: 10.1590/1678-7757-2017-0631. View

2.
Annamalai I, Bharathan K, Anbarasu P, Subramanian S . Deflection of mini implants from its intended path of placement on varying bone densities. J Clin Exp Dent. 2023; 14(12):e1000-e1007. PMC: 9799994. DOI: 10.4317/jced.59903. View

3.
Chatzigianni A, Keilig L, Reimann S, Eliades T, Bourauel C . Effect of mini-implant length and diameter on primary stability under loading with two force levels. Eur J Orthod. 2010; 33(4):381-7. DOI: 10.1093/ejo/cjq088. View

4.
Chen Y, Kyung H, Gao L, Yu W, Bae E, Kim S . Mechanical properties of self-drilling orthodontic micro-implants with different diameters. Angle Orthod. 2010; 80(5):821-7. PMC: 8939009. DOI: 10.2319/103009-607.1. View

5.
Chhatwani S, Kouji-Diehl O, Kniha K, Modabber A, Holzle F, Szalma J . Significance of bone morphology and quality on the primary stability of orthodontic mini-implants: in vitro comparison between human bone substitute and artificial bone. J Orofac Orthop. 2022; 84(6):362-372. PMC: 10587204. DOI: 10.1007/s00056-022-00385-8. View