Comparison of bone morphogenetic protein-2 delivery systems to induce supracrestal bone guided by titanium implants in the rabbit mandible

Objective To compare the ability of three non‐glycosylated/rhBMP‐2 (BMP‐2) delivery systems to induce supracrestal bone. Material and methods Thirty‐six custom SLActive dental implants were partially embedded in transverse orientation into the posterior mandibles of 18 adult rabbits with the head of the implant located 3 mm supracrestal. Delivery of BMP‐2 (30 μg) from the following materials was studied: (1) Ti implant + BMP‐2 with hydroxyapatite (HA)‐coated collagen (Col/HA) scaffold, (2) Ti implant with Col/HA infused with PEG hydrogel + BMP‐2, or (3) Ti implant with HA/β‐TCP/PEG hydrogel scaffold + BMP‐2. Scaffolds were secured with a metal “umbrella.” Non‐BMP‐2 contralateral controls were included. MicroCT imaging and histological analysis was performed after 10 weeks to assess new supracrestal bone formation. In vitro BMP‐2 release studies were conducted. Results All treatment groups displayed new supracrestal bone formation. Ti + BMP‐2 with Col/HA (3.0 ± 0.2 mm) and Ti with Col/HA/PEG hydrogel + BMP‐2 (2.7 ± 0.4 mm) had significantly greater (P