Treatment of human class II furcation defects using connective tissue grafts, bioabsorbable membrane, and resorbable hydroxylapatite: a comparative study.

Objective: To evaluate clinical outcomes and assess digital subtraction radiographic changes after using bioabsorbable membrane (polyglycolic acid/polylactic acid--PGA/PLA) or a connective tissue graft (CTG) as a barrier, with or without resorbable hydroxylapatite (HA Resorb) in the treatment of mandibular class II furcations.

Methods: Fifty furcations in twenty patients with chronic periodontitis were divided into five treatment groups: (I) PGA/PLA; (II) PGA/PLA and resorbable hydroxylapatite; (III) CTG; IV) CTG and resorbable hydroxylapatite; and (V) flap debridement alone (control). Vertical and horizontal probing depths, vertical probing attachment level, gingival recession and standardized periapical radiographs were obtained at baseline and at 3, 6 and 12 months post-operatively. At 12 months, the treated teeth were exposed by re-entry to verify clinical results.

Results: All experimental groups (I, II, III and IV) showed statistically significant improvement in the clinical parameters and bone density as compared to the control group. However, no statistically significant differences were observed among any of the experimental groups. Percentages of complete furcation closure and sites still defined as class II furcations were, respectively, as follows: 40% and 20-30% for groups II and IV; 20% and 40% for groups I and III; 0% and 80% for control. Groups II and IV showed significant radiographic changes in bone gain at both 6 and 12 months, while groups I and III showed significant changes only at 12 months.

Conclusions: (1) Guided tissue regeneration (GTR) therapy with or without resorbable hydroxylapatite showed significantly favorable results clinically and radiographically compared to flap debridement alone. (2) GTR plus resorbable hydroxylapatite (groups II and IV) showed higher percentages of complete furcation closure and more bone gain than GTR alone (groups I and III). (3) CTG may be used as an alternative to PGA/PLA bioabsorbable membrane with comparable potential. (4) Digital subtraction radiography may give higher accuracy in assessing results of periodontal therapy.