COMPARATIVE EFFECTS OF PLATELET-DERIVED GROWTH FACTOR-BB AND INSULIN-LIKE GROWTH-FACTOR-I, INDIVIDUALLY AND IN COMBINATION, ON PERIODONTAL REGENERATION IN MACACA-FASCICULARIS

Platelet-derived growth factor (PDGF) and insulin-like growth factor I (IGF-I) in combination have previously been shown to enhance periodon tal regeneration. The objective of this study was to further character ize the biological effects of this combination of growth factors in no n-human primates and compare the effects to those of each growth facto r individually. Ligature-induced periodontitis was initiated in 10 cyn omolgus monkeys, After periodontal lesions were established, surgery w as performed, and either a methylcellulose gel vehicle or vehicle cont aining 10 mu g each of either PDGF-BB, IGF-I or both PDGF-BB and IGF-I was applied to exposed root surfaces. Biopsies were taken 4 and 12 wk after treatment and the extent of periodontal regeneration was assess ed by histomorphometry, At both 4 and 12 wk vehicle-treated lesions ge nerally revealed minimal osseous defect fill (ODF) (8.5+/-2.1% and 14. 5+/-5.7%, respectively) and new attachment (NA) (34.1+/-5.2% and 26.6/-10.5%, respectively), IGF-I treatment did not significantly alter he aling compared to vehicle in any parameter at both 4 and 12 wk, PDGF-B B-treated sites exhibited significant (p<0.05) regeneration of NA (69. 6+/-12.0%) at 12 wk; trends for PDGF-BB treatment effect were also obs erved in other parameters at 4 and 12 wk, although these increases wer e not statistically significant. Treatment with PDGF-BB/IGF-I resulted in 21.6+/-5.1% and 42.5+/-8.3% ODF at 4 and 12 wk, respectively, and 64.1+/-7.7% and 74.6+/-7.4% NA at 4 and 12 wk, respectively (all signi ficantly greater than vehicle, p<0.05), The results from this study de monstrated that: 1) IGF-I alone at the dose tested did not significant ly alter periodontal wound healing; 2) PDGF-BB alone significantly sti mulated NA, with trends of effect on other parameters; and 3) the PDGF -BB/IGF-I combination resulted in significant increases in NA and ODF above vehicle at both 4 and 12 wk.