Bone loss after full-thickness and partial-thickness flap elevation

Fickl S, Kebschull M, Schupbach P, Zuhr O, Schlagenhauf U, Hürzeler MB. Bone loss after full‐thickness and partial‐thickness flap elevation. J Clin Periodontol 2011; 38: 157–162. doi: 10.1111/j.1600‐051X.2010.01658.x Objectives: The aim of this study was to histologically assess whether elevation of partial‐thickness flaps results in reduced bone alterations, as compared with full‐thickness flap preparations. Material and Methods: In five beagle dogs, both mandibular second premolars (split‐mouth design) were subjected to one of the following treatments: Tx1: elevation of a partial‐thickness flap over the mesial root of P2 and performing a notch at the height of the bone. Tx2: elevation of a full‐thickness flap over the mesial root of P2 and performing a notch at the height of the bone. After 4 months, sections were evaluated for: (i) vertical bone loss and (ii) osteoclastic activity using histometry. Results: Elevation of both full‐ and partial‐thickness flaps results in bone loss and elevated osteoclastic activity. Partial‐thickness flaps can result in less bone loss than full‐thickness flaps, but are subject to some variability. Conclusion: Use of partial‐thickness flaps does not prevent from all bone loss. The procedure may result most of the times in less bone loss than the elevation of full‐thickness flaps. Further research has to evaluate the determinants of effective outcomes of partial‐thickness flap procedures.