Horizontal Ridge Augmentation Using an rhBMP ‐2 Loaded Volume‐Stable Collagen Matrix Compared to Guided Bone Regeneration: A Preclinical In Vivo Study

Aim To investigate whether incorporation of recombinant human bone morphogenetic protein‐2 (rhBMP‐2) into a volume‐stable collagen matrix (VCMX) enhances horizontal ridge augmentation compared with VCMX alone or guided bone regeneration (GBR). Methods Chronic horizontal ridge defects were created in five canines. Sites randomly received: (1) control, (2) VCMX, (3) VCMX with rhBMP‐2 or (4) GBR (deproteinised bovine bone mineral with a collagen membrane). After 8 weeks, outcomes were assessed by profilometry, micro‐computed tomography and histomorphometry. Results VCMX/rhBMP‐2 showed significantly greater new bone volume (181.50 ± 142.32 mm 3 ) than GBR (36.06 ± 25.86), VCMX (8.40 ± 6.15) and control (7.32 ± 4.03 mm 3 ) (all p < 0.05). Histometric new bone thickness was greater in VCMX/rhBMP‐2 than GBR at all levels (crestal: 2.31 ± 1.93 vs. 1.09 ± 0.41 mm; p = 0.038). Coronal contour gain was higher in VCMX/rhBMP‐2 than VCMX ( p = 0.007), with no difference versus GBR ( p = 0.654). At middle and apical levels, all augmentation groups exceeded control ( p ≤ 0.011). Conclusions RhBMP‐2 delivered via VCMX enhanced horizontal bone regeneration with augmented dimensions comparable to GBR.