(13) Mini-implant based uprighting of impacted mandibular second molars: a case series

Thursday, September 15, 2022

1:30 PM – 3:00 PM CDT

Radiographic measurements

Example case

Presenting Author(s)

Jimmy-Tung Nguyen, DDS, MD

Resident
Oral & Maxillofacial Surgery Residency at LAC+USC Medical Center, Herman Ostrow School of Dentistry of USC
Los Angeles, California, United States

Co-Author(s)

PK

Peter Krakowiak, D.M.D. FACD, FRCD(C), FADSA, FICOI, FAAOMS

Clinical Assistant Professor
Herman Ostrow School of Dentistry of USC, LAC+USC Medical Center
Murrieta, California, United States

Disclosure(s):

Jimmy-Tung Nguyen, DDS, MD: No financial relationships to disclose

Peter Krakowiak, D.M.D. FACD, FRCD(C), FADSA, FICOI, FAAOMS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Abstract: Intro: Impacted mandibular second molars pose multiple problems in the developing arch. These include periodontitis, caries, and root resorption for the adjacent first molar and non-function and supra-eruption of the opposing dentition. Mini-implant assisted uprighting of impacted mandibular second molars serves as a theoretically safer alternative to traditional surgical uprighting. To date, this technique has been described in the literature only via case reports. The purpose of this study is to present the surgical technique and demonstrate the efficacy of uprighting impacting second mandibular molars with the assistance of mini-implants in a retrospective case series.

Materials &

Methods: This was a retrospective case series of 32 consecutive patients who underwent either unilateral or bilateral second molar uprighting with mini-implants, for a total of 42 teeth that received treatment. The patients ranged from 11-20 years old and were treated at Lakeshore Oral & Maxillofacial Surgery in Murrieta, CA and Lake Elsinore, CA from 2015-2021. In brief, the surgical procedure involved the following: the third molars were extracted, the second molars were exposed and had brackets bonded do them, a mini-implant was placed in the ascending ramus, and a Ni-Ti coil was connected to the two. Pre-operative angles and depths of impaction, length of treatment, and post-treatment radiographic bone levels of the uprighted mandibular second molars were measured. Treatment was considered completed once the mesial marginal ridge of the impacted second molar had cleared the undercut of the distal of the first molar.

Results: The mean age at initiation of treatment was 13.88 ± 2.10 years. The mean, median, and mode of length of treatment was 169.24 ± 197.33 days, 93 days, and 64 days, respectively. The mean angle of impaction was 43.27 ± 21.29 degrees. The mean depth of impaction was 7.36 ± 21.04 mm. The mean post-treatment mesial bone level of the second molar was 2.26 ± 1.11. Of the 42 teeth treated, 18 required repositioning of the bonded bracket or repositioning of the mini-implant at follow-up. There were no incidences of post-treatment periapical radiolucencies or root resorption of the second molars.

Conclusion: Mini-implant assisted uprighting of impacted second mandibular molars is an effective method of uprighting impacted mandibular molars with a wide range of degree of impaction. It serves as a promising treatment that is faster than orthodontic movement alone yet safer than traditional surgical uprighting.

References:
1. Padwa BL, Dang RR, Resnick CM. Surgical Uprighting Is a Successful Procedure for Management of Impacted Mandibular Second Molars. J Oral Maxillofac Surg. 2017 Aug;75(8):1581-1590. doi: 10.1016/j.joms.2017.02.027. Epub 2017 Mar 14. PMID: 28388395.
2. Magkavali-Trikka P, Emmanouilidis G, Papadopoulos MA. Mandibular molar uprighting using orthodontic miniscrew implants: a systematic review. Prog Orthod. 2018 Jan 8;19(1):1. doi: 10.1186/s40510-017-0200-2. PMID: 29308540; PMCID: PMC5756736.