Particulate Versus Cross-Linked Collagenated Bone Substitutes for Guided Bone Regeneration: A Randomized Controlled Trial

Aim: To compare the dimensional outcomes of horizontal augmentation with the retentive-flap technique using particulate and cross-linked collagenated bone substitutes. Materials and Methods: This two-centre, two-arm randomized clinical trial investigated 69 subjects: 34 in the particulate group and 35 in the collagenated group. Patients were randomly assigned to receive single implant placement with simultaneous guided bone regeneration (GBR) using either particulate deproteinized porcine bone material (DPBM) or cross-linked collagenated DPBM. Quantitative evaluations were conducted for horizontal width, augmented area, and augmented volume in both hard and soft tissue dimensions. Results: Immediately after surgery, the collagenated group exhibited higher hard tissue dimensions in terms of horizontal width and augmented area. After 4 months, the difference between the two groups decreased to a non-significant level, mainly attributable to the high shrinkage rate of the collagenated group (32.32 [20.79] %) compared to the particulate group (19.90 [14.33] %). No significant difference was observed regarding the soft tissue contour analyses between the two groups after 4 months. Conclusions: There were no significant differences between cross-linked collagenated and particulated DPBMs regarding the dimensional outcomes of horizontal augmentation with the retentive-flap technique. The high resorption rate of the collagenated bone substitute negates its initial superiority in both radiographic and soft tissue dimensions (no. KCT0005348).