Regeneration of class III furcation defects with basic fibroblast growth factor (b-FGF) associated with GTR. A descriptive and histometric study in dogs

Background: The poor predictability of periodontal regenerative treatment o f Class III furcation defects stimulates the study of alternatives to impro ve its results, such as the use of polypeptide growth factors. The objectiv e of this study was to evaluate, both histologically and histometrically, t he effects of topical application of basic fibroblast growth factor (b-FGF) associated with guided tissue regeneration (GTR) in the treatment of Class III defects surgically induced in dogs. Methods: All second and fourth premolars of 5 mongrel dogs were used and ra ndomly assigned to one of three treatment groups: group 1 (control), treate d with scaling and root planing, tetracycline hydrochloride (125 mg/ml) con ditioning, and GTR with a collagen membrane; group 2, same treatment as gro up 1 plus 0.5 mg of b-FGF; group 3, same treatment as group 1 plus 1.0 mg o f b-FGF. After a 90-day healing period, routine histologic processing and s taining with hematoxylin and eosin and Masson trichrome were performed. Results: The descriptive analysis indicated better regenerative results in both groups treated with b-FGF while the histometric data, analyzed by mean s of analysis of variance (ANOVA), showed greater filling of the defects in group 2 in comparison to the defects in groups 3 and 1, respectively, whic h was represented by a smaller area of plaque-occupied space (P = 0.004) as well as a greater amount of newly formed cementum (P = 0.002). Conclusions: These results indicate that b-FGF, especially in smaller doses , may enhance the regenerative results in Class III furcation lesions, lead ing to greater filling of these defects with both mineralized and non-miner alized tissues.