Introduction: Surgery is one treatment modality for periodontal diseases that can stimulates osteoclastic activity
and results in resorption of alveolar crestal bone. The aim of this study was to compare the effect of two procedures
of periodontol surgery on resorption of alveolar crestal bone.
Materials & Methods: Twenty patients were selected from patients referred to our dental school. After initial
therapy, the surgical treatments were performed by a surgeon and the study was performed with split mouth design.
One side was treated with an apically positioned flap (APF) with bone exposure (20 quadrants) and on the opposite
side APF without bone exposure (20 quadrants). At the time of surgery the distance between CEJ to bone crest was
recorded. After two months, the patients were examined for the same parameters using the bone sounding
technique.
Results: According to the results, in sites with apically positioned flap with bone exposure, crestal resorption was
0.77±0.63 and on the opposite side it was 1.05±0.79 mm. The difference between the two sides was not significant.
Pocket changes were significant in both techniques but there was not any significant differences between the two
procedures.
Conclusion: According to the results of this study, similar alveolar crestal bone resorption occurred during the
healing process in the two procedures and this resorption may have an important role in reconstruction of biologic
width.
Key words: Apically positioned flap, crestal bone loss, bone exposure.