Efecto de las técnicas de sellado alveolar con injerto epitelial libre vs matriz colágena porcina en los procedimientos de preservación alveolar

Abstract

Introduction: Alveolar preservation procedures (ARP) are predictable techniques used to minimize both bone resorption and soft tissue collapse following tooth extraction, thereby facilitating implant placement in the ideal three-dimensional position. Objective: The aim of this clinical trial was to compare and analyze the volumetric and linear changes in tissue following two types of alveolar preservation. Material and Methods: A clinical trial was conducted including patients requiring tooth extractions in non-molar areas. Test group: 10 sockets were filled with 10% collagen-deproteinized bovine bone mineral (DBBM-C) and sealed with a bilayer porcine collagen membrane (MC). Control group: 10 sockets were filled with DBBM-C and sealed with autologous free epithelial graft (EFG). Volumetric change was analyzed at 3 and 6 months after surgery using stereolithographic (.stl) model superimposition and a custom-made acrylic stent was used as a reference for linear measurements of the alveolar crest. Statistical analyses were performed using sample t-test, Mann-Whitney test, paired t-test, and Wilcoxon test. Results: The mean volumetric change at 6 months was -37.2 ± 45.01 mm3 for the control group and -13.78 ± 26.32 mm3 for the test group. There were no statistically significant differences between groups (T-Test p=0.173). The mean horizontal changes in soft tissue during the 6 months of healing at 1 mm (D7), 3 mm (D8) and 5 mm (D9) from the gingival margin were -2.5 mm ± 1.03 mm, -1.89 ± 1.04 mm and -2.18 ± 2.27 mm respectively for the control group and -1.58 ± 0.96 mm, -0.67 ± 1.08 mm and -0.69 ± 0.84 mm respectively for the test group. There were significant differences in the changes at 3 and 5 mm from the gingival margin when comparing the control and test groups (T test p = 0.02 and M-W p = 0.044). At the mesial papilla (D1), the mean change for the control group was 0.7 ± 0.82 mm and for the test group 1.1 ± 0.88 mm. At the midpoint of the vestibular margin (D2), changes of 0.6 ± 1.17 mm were recorded for the control group and 0.9 ± 0.74 mm for the test group. At the distal papilla (D3), changes were 1.1 ± 0.74 mm for the control group and 1 ± 0.94 mm for the test group. Finally, at the midpoint of the palatal gingival margin, changes were 1.9 ± 1.52 mm for the control group and 1.2 ± 1.03 mm for the test group. Vertical changes in soft tissues did not show significant differences between groups. The mean vertical bone changes in the buccal bone crest (D5) were 0.7 ± 1.77 mm in the control group and 0.9 ± 1.45 mm in the test group. In the palatal bone crest (D5), a mean change of 1.3 mm ± 0.67 mm was recorded for the control group and 1.2 ± 1.14 mm for the test group. No statistically significant differences were found when the changes between both groups were compared (D5: M-W p= 1.00; D6: M-W p=0.427). Conclusions: In general, the differences obtained in terms of volumetric and lineal changes are small between the groups studied. The application of a xenogeneic porcine soft tissue substitute as an alveolar sealing material after tooth extraction is found to be safe and maintains the volume of the socket in a similar way to the application of an epithelial-connective graft.