The Use of Microimplants in Orthodontic Anchorage

Chen, Chung-Ho; Chang, Chao-San; Hsieh, Chi-Hsin; Tseng, Yu-Chuan; Shen, Yee-Shyong; Huang, I.-Yueh; Yang, Chia-Fu; Chen, Chun-Ming

doi:10.1016/j.joms.2006.04.016

« Previous Next »Journal of Oral and Maxillofacial Surgery
Volume 64, Issue 8 , Pages 1209-1213, August 2006

The Use of Microimplants in Orthodontic Anchorage

Chung-Ho Chen, DDS
- Associate Professor, Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University, Kaohsiung, Taiwan.
Chao-San Chang, DDS, PhD
- Assistant Professor, Department of Orthodontics, Kaohsiung Medical University, Kaohsiung, Taiwan.
Chi-Hsin Hsieh, DDS, MDS
- Graduate Student, Graduate Institute of Dental Sciences, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
Yu-Chuan Tseng, DDS, MDS
- Visiting Staff, Department of Orthodontics, Kaohsiung Medical University, Kaohsiung, Taiwan.
Yee-Shyong Shen, DDS
- Instructor, Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University, Kaohsiung, Taiwan.
I.-Yueh Huang, DDS, MDS
- Instructor, Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University, Kaohsiung, Taiwan.
Chia-Fu Yang, DDS
- Visiting Staff, Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University, Kaohsiung, Taiwan.
Chun-Ming Chen, DDS, MDS
- Assistant Professor, Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University, Kaohsiung, Taiwan.
- Address correspondence and reprint requests to Dr C-M Chen: Department of Oral Maxillofacial Surgery, Kaohsiung Medical University, No. 100, Shih-chuan 1st Road, Kaohsiung 807, Taiwan

Purpose

Various types of temporary implants have been introduced to serve as orthodontic anchorage. The hypothesis of this study is that microimplants of 1.2 mm diameter can be used as orthodontic anchors, and that their success is related to their length. The aim of this study is to determine the incidence of anchor retention after orthodontic force application for moving teeth, and to determine the relationship of microimplant length to retention rate.

Methods

Fifty-nine microimplants (diameter: 1.2 mm) were placed in 29 patients as orthodontic anchorages. After 2 weeks of microimplant placement, a force of 100 to 200 g was loaded with an elastometric chain or NiTi coil spring. Risk factors were characterized as to why a microimplant may fail, and Fisher’s exact test was used for statistical analysis.

Results

Nine microimplants were removed and the overall success rate was 84.7%. Exploring the causes for failure, we found significant differences between the length of microimplants and success rate; 6 mm was 72.2% and 8 mm was 90.2%.

Conclusions

The results suggest that microimplants are suited as an alternative orthodontic anchorage. We recommend that 8-mm microimplants are preferable to 6-mm.