Assessment of Corticotomy Facilitated Tooth Movement and Changes in Alveolar Bone Thickness - A CT Scan Study

Abstract

Introduction: Corticotomy is an effective method of accelerating the orthodontic treatment. The aim of this study was to compare the treatment time for the extraction space closure, between corticotomy assisted and conventional orthodontic tooth movement and to check the alveolar bone thickness before and after corticotomy procedure in the corticotomy group.

Settings and design: Cross-sectional clinical study.

Materials and methods: Twenty patients (age>15 y) requiring orthodontic treatment with upper anterior retraction in the extraction space of 1(st) premolar were selected and were randomised into control and corticotomy group each group consisted of 10 subjects. Pre retraction, corticotomy was performed in the maxillary anterior segment. The pre and post retraction CT scans were recorded and the thickness of the alveolar plates were measured at crestal level (S1), mid root level (S2) and apical level (S3) PreTreatment (T1). The same measurements were repeated after incisor retraction was completed PostTreatment (T2).

Statistical analysis: Student's t-test, Pearson correlation coefficient.

Results: There was a significant difference in retraction time (days) between control and corticotomy groups (p<0.001). Also, there were significant difference in total alveolar bone thickness at the crest region for all the four incisor teeth (p<0.05). A significant difference was observed in total alveolar bone thickness at the S2 and S3 level for 11, 21 and 11, 12 and 22 (p<0.05) respectively.

Conclusion: Alveolar corticotomies not only accelerates the orthodontic treatment but, also provides the advantage of increased alveolar width to support the teeth and overlying structures.

Keywords: Corticotomy facilitated orthodontics; Periodontally accelerated osteogenic orthodontics; Regional acceleratory phenomena.

Figures

[Table/Fig-1]:

Upper arch with 0.16 x 0.22 stainless steel wire in place

[Table/Fig-2a]:

Mucoperiosteal flap reflected and vertical and horizontal corticotomy cuts placed along with alveolar perforations on buccal side

[Table/Fig-2b]:

Mucoperiosteal flap reflected and vertical and horizontal corticotomy cuts placed along with alveolar perforations on buccal side

[Table/Fig-3a]:

Bone graft placed over the corticotomized area (buccal surface)

[Table/Fig-3b]:

Bone graft placed over the corticotomized area (palatal surface)

[Table/Fig-4]:

Sutures placed after the completion of corticotomy procedure

[Table/Fig-5]:

Retraction started using niti closed coil spring

[Table/Fig-6]:

Space closure after 4 months of active orthodontic treatment

[Table/Fig-7]:

GE bright speed 16 ct scan machine

[Table/Fig-8a, b, c]:

Evaluation of alveolar bone thickness in maxillary slice at crestal level (S1), mid root level (S2), and apical level (S3)

[Table/Fig-10]:

Comparison of retraction time in control and corticotomy groups (days) by t-test

[Table/Fig-12]:

Comparison of pretreatment and post-treatment alveolar bone thickness at s1,s2,s3 levels by paired t-test