INTRODUCTION: This article illustrates a new surgical guide system that uses cone-beam computed tomography (CBCT) images to replicate dental models; surgical guides for the proper positioning of orthodontic mini-implants were fabricated on the replicas, and the guides were used for precise placement. The indications, efficacy, and possible complications of this method are discussed.

METHODS: Patients who were planning to have orthodontic mini-implant treatment were recruited for this study. A CBCT system (PSR 9000N, Asahi Roentgen, Kyoto, Japan) was used to acquire virtual slices of the posterior maxilla that were 0.1 to 0.15 mm thick. Color 3-dimensional rapid prototyping was used to differentiate teeth, alveolus, and maxillary sinus wall. A surgical guide for the mini-implant was fabricated on the replica model. Proper positioning for mini-implants on the posterior maxilla was determined by viewing the CBCT images.

RESULTS: The surgical guide was placed on the clinical site, and it allowed precise pilot drilling and accurate placement of the mini-implant.

CONCLUSIONS: CBCT imaging allows remarkably lower radiation doses and thinner acquisition slices compared with medical computed tomography. Virtually reproduced replica models enable precise planning for mini-implant positions in anatomically complex sites.

Source:

Am J Orthod Dentofacial Orthop. 2007 Apr;131(4 Suppl):S82-9

Surgical positioning of orthodontic mini-implants with guides fabricated on models replicated with cone-beam computed tomography.

Kim SH, Choi YS, Hwang EH, Chung KR, Kook YA, Nelson G. Department of Orthodontics, Catholic University of Korea, Uijongbu St. Mary’s Hospital, Seoul, Korea. bravortho@catholic.ac.kr

Thu August 07 2008