Evaluating the osteogenic potential of insulin-like growth factor-1 microspheres on osteoblastic activity around dental implants in patients with type 2 diabetes mellitus using bone scintigraphy: A split-mouth randomized controlled trial.

STATEMENT OF PROBLEM: Dental implants are susceptible to early failure when placed in patients diagnosed with type 2 diabetes mellitus. The osteoinductive potential of insulin-like growth factor-1 (IGF-1) has been widely investigated in animals with type 2 diabetes mellitus, but studies investigating the osteoinductive potential of IGF-1 around dental implants in patients diagnosed with type 2 diabetes mellitus are lacking. PURPOSE: This randomized controlled trial was conducted to assess the osteogenic efficacy of poly(lactide-co-glycolide)- (PLGA) encapsulated IGF-1 microspheres around dental implants placed in patients diagnosed with type 2 diabetes mellitus. MATERIAL AND METHODS: A split-mouth, randomized controlled trial was conducted in 10 participants diagnosed with type 2 diabetes mellitus and with bilaterally missing mandibular posterior teeth. The 20 sites were randomly allotted to receive the PLGA encapsulated IGF-1 or placebo microspheres followed by the placement of O3.8x11-mm implants. Osteoblastic activity was quantitatively assessed with bone scintigraphy scanning on the thirtieth, sixtieth, and 90th day after implant placement. The Shapiro-Wilks test was used to analyze the normality of data, followed by the independent t test to compare the experimental and placebo groups. Intragroup comparison was performed by using repeated-measures ANOVA and the post hoc Bonferroni test (alpha=.05). RESULTS: Statistical analysis revealed that the mean osteoblastic activity was higher in the experimental group which received the PLGA-encapsulated IGF-1 than in the placebo group at the 30th, 60th, and 90th day after implant placement (P