Soft Tissue changes after using Collagen Matrix Seal or Collagen Sponge with Allograft in Ridge Preservation:A Randomized Controlled Volumetric Study.

: The objective of this study is to assess alterations in buccal soft tissue contour after alveolar ridge preservation (ARP) using either a collagen matrix seal (CMS) or a collagen sponge (CS) as barriers with freeze-dried bone allograft (FDBA). Participants (28 total) were randomly assigned into the CMS group or the CS group (14 each). The same clinical steps were used in both barriers. Cast models were taken at the baseline and at 4 months, then both models were optically scanned and digitally superimposed. Volumetric, surface, and distance-adjusted measurements were calculated to assess buccal soft tissues alterations. Surface area and volume loss in the CMS group were observed to be 71.44±1189.09 mm 2 and 239.58±231.89 mm 3 . The CS group showed measurements of 139.56±557.92 mm 2 and 337.23±310.18 mm 3, . Mean buccal soft tissue loss and minimum-maximum distance loss were less in the CMS (0.88±0.52 mm, and 0.2-2.15 mm respectively), compared with the CS group (1.63±1.03 mm and 0.3-3.68 mm respectively) with no statistically significant difference between the groups (p=0.2742). Both alveolar ridge preservation barriers were unable to entirely prevent soft tissue contour changes after extraction. However, collagen matrix seal application was slightly better in minimizing the amount of soft tissue reduction compared to the collagen sponge. ClinicalTrials.gov (NCT02697890).