Comparative Evaluation of Synthetic and Xenogeneic Self‐Retaining Bone Grafting Systems Under Standardized Block Geometry: An Experimental In Vivo Study

OBJECTIVES: This study aimed to compare new bone formation and dimensional outcomes between synthetic and xenogeneic self-retaining bone grafting systems in staged alveolar ridge augmentation (ARA) for severe bone defects. METHODS: Eight beagle dogs underwent bilateral extraction of the maxillary premolars, followed by an 8-week healing period allowing natural alveolar ridge defects. In a split-mouth design, each animal received both treatments on contralateral sides, with side allocation determined by a computer-generated randomization sequence: a self-retaining synthetic bone block (srSB) with particulate synthetic bone (SP), or a self-retaining xenogeneic block (srXB) with particulate xenogeneic bone (XP), each covered with a collagen membrane. After an additional 8-week healing period, radiographic and histomorphometric analyses were performed. Linear measurements showed no significant difference in the total augmented buccopalatal width. The horizontal distance to the most buccally located newly formed bone was greater in the srSB group in the mid-portion of the augmented compartment, reaching significance at 3 mm apical to the alveolar crest after Holm-Bonferroni correction (mean difference 3.57 mm, 95% CI 1.84-5.30, adjusted p = 0.025). CONCLUSION: The synthetic self-retaining grafting system showed greater new bone formation than the xenogeneic system after 8 weeks of healing in this canine model.