PERIODONTAL REGENERATION IN NATURALLY-OCCURRING CLASS-II FURCATION DEFECTS IN BEAGLE DOGS AFTER GUIDED TISSUE REGENERATION WITH BIOABSORBABLE BARRIERS

THE EFFICACY OF A BIOABSORBABLE polylactic acid based barrier was eval uated using naturally occurring buccal Class II furcation defects in b eagle dogs, Sixteen furcation sites (8 control and 8 experimental) wer e treated in 6 adult animals. After full thickness flap reflection, ex posed furcations and root surfaces were thoroughly root planed. In exp erimental sites a customized barrier was formed and fitted to cover th e defect. Surgical flaps were replaced slightly coronal to the cemento -enamel junction. Animals were sacrificed at 6 months and specimens pr ocessed for histologic evaluation. Histologic and histometric analyses were done using 6 mu m step serial sections in the buccal-lingual pla ne, corresponding to the buccal-lingual extent of the furcation. Resul ts were: mean total defect experimental sites 1.92 mm; control sites 1 .47 mm. Mean new cementum formation experimental sites 1.36 mm (71% of initial defect); control sites 0.25 mm (17% of initial defect). Mean new bone formation experimental sites 1.42 mm (74% of initial defect); control sites 0.20 mm (14% of initial defect). Mean junctional epithe lium formation experimental sites 0.42 mm (22% of initial defect); con trol sites 1.21 mm (82% of initial defect). Statistical analysis demon strated significant differences in all healing parameters favoring exp erimental (barrier-treated) sites, In this model, regeneration (new bo ne, cementum, and periodontal ligament) of 71% of the original defect in experimental sites and only 14% in control sites demonstrated a res ponse that highly favored use of the barrier.