Soft tissue outcomes following alveolar ridge preservation with/without primary flap closure for periodontally damaged extraction socket: A randomized clinical trial

Introduction: The changes in soft tissue profile following alveolar ridge preservation (ARP) with/without primary flap closure (PC) in periodontally damaged sockets have yet to be discovered. Methods: For periodontally damaged non-molar extraction sockets, ARP with PC (group PC)/without PC (group SC) was performed using granule-type xenogeneic bone substitute material and a collagen barrier. Intraoral scans were performed at the time of ARP and 4 months thereafter. Superimposition of STL files was performed to examine tissue change on the soft tissue level. The level of mucogingival junction (MGJ) was also evaluated. Results: A total of 28 patient (13 in group PC, 15 in group SC) completed the study. Soft tissue profile change was evaluated only when the measurement level was located on the non-mobile tissue. Group PC tended to shrink less on the long axis of the extraction socket than group SC (−4.3 ± 3.1 mm vs. −5.9 ± 4.4 mm at the 1 mm below the pre-extraction gingival margin, p > 0.05). Profilometric analysis (on the region of interest) also have a tendency of less tissue profile change in group PC than group SC (−1.0 ± 0.8 mm vs. −1.3 ± 0.5 mm, p > 0.05). The MGJ level change was not statistically significantly different between the groups (p > 0.05) even though the MGJ level was located more apically at 4 months in group SC compared with group PC. Conclusions: Alveolar ridge preservation with PC tended to yield less soft tissue shrinkage than ARP without PC.