# Clinical and Histological Outcomes of Autologous Dentin Matrix in Post-Extraction Alveolar Healing: A Pilot Randomized Clinical Trial

## TL;DR

This pilot study explores how autologous dentin matrix affects early healing after tooth extraction, comparing it to other grafting methods.

## Contribution

The study provides initial clinical evidence on the biological behavior of autologous dentin matrix in post-extraction healing.

## Key findings

- BMP4 expression was detected in 67.9% of histological fields, mainly in osteocytic and osteoblastic areas.
- No statistically significant differences in healing outcomes were found between the tested groups.
- ADM showed consistent biological behavior during early alveolar healing without adverse events.

## Abstract

Background/Objectives: Autologous dentin matrix (ADM) has been suggested as a biologically plausible biomaterial for alveolar bone regeneration after tooth extraction. However, clinical evidence regarding its biological activity and early healing outcomes is limited. This exploratory, randomized controlled pilot study aimed to descriptively assess early alveolar healing patterns and bone morphogenetic protein 4 (BMP4) expression following tooth extraction using ADM compared with other grafting approaches. Methods: Patients requiring tooth extraction were allocated to one of four groups: ADM, xenograft, ADM combined with platelet-rich fibrin, and a graft-free control group. Histological and immunohistochemical analyses were performed four months after extraction to descriptively assess cellular features of healing and BMP4 expression. The trial was registered at the Brazilian Registry of Clinical Trials (ReBEC; RBR-24mdgrf) and conducted under prior ethics committee approval. Results: BMP4 expression was detected in 67.9% of the analyzed histological fields, predominantly localized in osteocytic, osteoblastic, and medullary areas. Although descriptive differences in BMP4-positive fields were observed among the groups, no statistically significant differences were identified between the groups. Histological evaluation revealed an active cellular environment across all treatment modalities, consistent with early post-extraction healing. No adverse events related to surgical procedures or grafting materials were reported during the study period. Conclusions: Within the limitations of this pilot randomized clinical trial, ADM exhibited consistent biological behavior during early post-extraction alveolar healing. The observed BMP4 expression likely reflects a general physiological healing response rather than a material-specific effect. This finding supports the biological plausibility of dentin-derived grafts as osteoconductive biomaterials. These findings are hypothesis-generating, and larger, adequately powered randomized clinical trials with standardized molecular and histological assessments are required to determine their clinical relevance.