Evaluation of alveolar cortical bone thickness and density for orthodontic mini-implant placement

M Cassetta,E Barbato,Aaa Sofan,F Altieri

doi:10.4317/jced.51228

Abstract

Objective: Mini-implant stability is primarily related to bone quality and quantity. This study evaluated alveolar cortical bone thickness and density differences between interradicular sites at different levels from the alveolar crest, and assessed the differences between adolescents (12-18 years of age) and adults (19-50 years of age), males and females, upper and lower arch, anterior and posterior region of jaws and buccal and oral side. Study Design: In this retrospective study, 48 Computed Tomography scans, performed for oral surgery purposes were selected from dental records of 3,223 Caucasian orthodontic patients. The SimPlant software (Materialise, Leuven, Belgium) was used to measure cortical bone thickness and density at 13 interradicular sites and four bone levels ( 2,4,6 and 8 mm ). For the statistical analysis descriptive statistics, Student’s t-test and Pearson correlation coefficient were used. Results: Statistically significant differences in alveolar cortical bone thickness and density between age, gender, sites and sides were found (P<0.05). The Pearson correlation coefficient demonstrated a significant linear increasing of thickness and density from crest to base of alveolar crest (P≤0.05). Conclusion. Adults show a thicker alveolar cortical bone than adolescents. Alveolar cortical bone thickness and density were greater in males than in females, in mandible than in maxilla, in the posterior region than the anterior, in oral than buccal side. There is an increase of thickness and density from crest to base of alveolar crest. Key words:Orthodontics, cortical bone thickness, cortical bone density, mini-implant, computed tomography, temporary anchorage devices.

Highlights

Strategies for anchorage control have been a major factor in achieving successful orthodontic treatment
Bone density was measured using Hounsfield units (HU), which are directly associated with tissue attenuation coefficients
Several studies have proposed a variety of methods for assessing bone density, but in recent years, the use of a computerized tomography (CT) scan has been common for preoperative quantitative and qualitative assessment of implant sites, and the Hounsfield Unit (HU) is routinely used to determine the bone density objectively [19,20]

Summary

Introduction

Strategies for anchorage control have been a major factor in achieving successful orthodontic treatment. Several studies found that the stability of TAD is affected by age, sex, craniofacial skeletal pattern, site and side of implantation, latent period, loading protocol, dimension and angulation of TAD, insertion torque, degree of TAD-bone contact, quality and quantity of the cortical bone, degree of inflammation of the peri-TAD-tissue, thickness and mobility of the soft tissue, and root proximity [1,2,3,4,5,6] For these reasons, research has been conducted on the stability of mini-implants used for orthodontic purposes. The hypotheses were that there are no differences in alveolar cortical bone thickness and density between, males and females, adolescents and adults, upper and lower arch, anterior and posterior area of the jaws, between buccal and oral side and from crest to base of alveolar crest

Methods

Results

Conclusion