Bone density at interradicular sites: implications for orthodontic mini-implant placement.
OBJECTIVE
Implant stability is primarily related to local bone density; Few studies have evaluated interradicular bone density related to mini-implant placement for orthodontic anchorage. Therefore, this study evaluated bone density differences between interradicular sites.


METHODS
Computed tomographic (CT) images were obtained from 14 males and 14 females (mean age 27 years, range 23-35 years). Bone density in Hounsfield units (HU) was measured at 13 interradicular sites and four bone levels.


RESULTS
Bone densities in most areas were higher than 850 HU. Statistically significant differences in bone density were detected at different levels and sites. Bone densities in both maxilla and mandible significantly increased from the alveolar crest toward basal bone in posterior areas, while the opposite was observed in anterior areas. There were statistically significant differences in bone densities between the maxilla and mandible in posterior areas. Bone densities progressively increased from anterior to posterior areas in the mandible.


CONCLUSIONS
The results suggest that mini-implants for orthodontic anchorage may be effective when placed in most areas with equivalent bone density up to 6 mm apical to the alveolar crest. Site selection should be adjusted according to bone density assessment.
Chun
Y S
YS
Division of Orthodontics, Department of Dentistry, Ewha Womans University, Seoul, Korea.
Lim
W H
WH
D000328:Adult; D000539:Alveolar Process / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D015519:Bone Density; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D005260:Female; D006801:Humans; D008297:Male; D008904:Miniaturization; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed; D055815:Young Adult
D015921:Dental Implants