GUIDED TISSUE REGENERATION AND ANTIINFECTIVE THERAPY IN THE TREATMENTOF CLASS-II FURCATION DEFECTS

THE PURPOSE OF THE PRESENT STUDY WAS TO EVALUATE the effect of anti-in fective therapy on the success of periodontal regeneration in mandibul ar Class II furcation defects. Eighteen patients with mandibular bilat eral Class II furcation defects were enrolled. Following an initial hy gienic phase, guided tissue regeneration (GTR) was performed using an expanded polytetrafluoroethylene (e-PTFE) membrane barrier. The area w as surgically exposed, thoroughly root planed, and irrigated with eith er tetracycline (100 mg/ml) or 0.9% saline. Post-operative care includ ed systemic tetracycline (250 mg q.i.d.) and chlorhexidine 0.12% mouth wash twice daily. Patients were maintained on a prophylaxis schedule o f every 2 weeks for the first 3 months, and monthly thereafter. Clinic al parameters of probing depth (PD), probing attachment level - vertic al (PAL-v), probing attachment level - horizontal (PAL-h), and target periodontal pathogens were monitored at baseline and quarterly for one year. An overall improvement in all clinical parameters was observed in both groups: probing reduction (3.1 mm), PAL-h gain (2.3 mm), and P AL-v gain (1.2 mm) were all statistically significant compared to base line measurements. Vertical measurements were performed parallel to th e long axis of the tooth with no attempt to angulate the probe into th e furcation. There was no significant difference in sites receiving te tracycline. A strong positive correlation was noted between initial PD and pocket reduction (r = 0.77, P <0.0001) and between initial PD and PAL-h gain (r = 0.54) and PAL-v gain (r = 0.45) suggesting that initi al probing depth might be used to assess the regenerative potential of a given site. PD and PAL have shown marked improvement as early as 6 months post-operatively, but further improvement occurred over the 12 months of the study. Mean plaque indices were reduced to 0.5 with slig ht increases at 9 months, while gingival indices were steady at 0.5 th rough the year. Immunofluorescence demonstrated minimal infection with the target periodontal pathogens following surgery. Actinobacillus ac tinomycetemcomitans was detected in 5 sites during the monitoring phas e and was associated with less favorable clinical results. This findin g suggests that anti-infective therapy and monitoring for A. actinomyc etemcomitans and/or other periodontal pathogens might be useful in GTR therapy.