Influence of healing time on the outcomes of alveolar ridge preservation using a collagenated bovine bone xenograft: A randomized clinical trial

AbstractAimTo evaluate the healing outcomes in non‐molar post‐extraction sockets filled with deproteinized bovine bone mineral with collagen (DBBM‐C) as a function of time.Materials and MethodsPatients in need of non‐molar tooth extraction were randomly allocated into one of three groups according to the total healing time (A—3 months; B—6 months; C—9 months). The effect of alveolar ridge preservation (ARP) therapy via socket filling using DBBM‐C and socket sealing with a porcine collagen matrix (CM) was assessed based on a panel of clinical, digital, histomorphometric, implant‐related, and patient‐reported outcomes.ResultsA total of 42 patients completed the study (n = 14 in each group). Histomorphometric analysis of bone core biopsies obtained at the time of implant placement showed a continuous increase in the proportion of mineralized tissue with respect to non‐mineralized tissue, and a decrease in the proportion of remaining xenograft material over time. All volumetric bone and soft tissue contour assessments revealed a dimensional reduction of the alveolar ridge overtime affecting mainly the facial aspect. Linear regression analyses indicated that baseline buccal bone thickness is a strong predictor of bone and soft tissue modelling. Ancillary bone augmentation at the time of implant placement was needed in 16.7% of the sites (A:2; B:1; C:4). Patient‐reported discomfort and wound healing index scores progressively decreased over time and was similar across groups.ConclusionsHealing time influences the proportion of tissue compartments in non‐molar post‐extraction sites filled with DBBM‐C and sealed with a CM. A variable degree of alveolar ridge atrophy, affecting mainly the facial aspect, occurs even after performing ARP therapy. These changes are more pronounced in sites exhibiting thin facial bone (≤1 mm) at baseline (Clinicaltrials.gov NCT03659617).