EVALUATION OF TETRACYCLINE FIBER THERAPY WITH DIGITAL IMAGE-ANALYSIS

The aims of the present study were to assess radiographically the effe cts of scaling/root planing combined with antibiotic therapy using tet racycline fibers (TCF): (I) on alveolar bone density and linear descri ptors and (II) on supracrestal soft tissue density. 19 subjects with g eneralized adult periodontitis (with at least 20 teeth present, at lea st 4 teeth with pockets greater-than 4 mm and bleeding upon controlled force probing) and high cultural counts of Porphyromonas gingivalis w ere recruited from a pool of 57 patients. The full mouth treatment gro up (FT) consisted of 10 patients, who underwent a full mouth supra-gin gival scaling and prophylaxis treatment and were instructed to rinse 2 X daily with a 0.1% chlorhexidine solution. 1 week later, tetracycline -hydrochloride-containing fibers (Actisite(R) periodontal fiber) were applied around all teeth. After 7-12 days, the fibers were removed and all teeth were scaled and root planed under local anaesthesia. The ch lorhexidine rinsing continued for another 2 months. In 9 subjects (loc al treatment group LT), 2 teeth with periodontal lesions with pocket p robing pepth (PPD) greater-than-or-equal-to 5 mm were treated by place ment of tetracycline fibers, which remained in place for 7 to 12 days. Upon removal of the fibers, scaling and root planing was performed on these 2 teeth, while the rest of the dentition remained untreated, an d no chlorhexidine rinse was applied. 2 of the untreated teeth reveali ng similar periodontal lesions were chosen to represent sites affected by untreated periodontitis (NT). In this group, a limited local treat ment was performed (2 teeth) with the inherent potential for recoloniz ation from the untreated pocket sites. Standardized periapical radiogr aphs were obtained from the 4 monitored sites within each patient at b aseline (before treatment) and 2 and 6 months thereafter. One radiogra ph was exposed in a standard way for bone assessment. The second radio graph was underexposed, at about a 1/5 of the original exposure time t o allow the evaluation of soft tissue. Mean changes in the linear para meters and changes in density (CADIA) observed at multiple sites withi n each patient and treatment group were used as the best estimate of t reatment outcome. Over the observation period of 6 months, a significa nt difference in bone height changes was found between the untreated s ites (median loss -0.29 mm) and the sites from full-mouth treated pati ents (median gain 0.24 mm, p=0.008). When comparing the baseline to th e 6 months radiographs, a loss in bone density was observed for the un treated group (median=-2.13 CADIA). Both treatment groups revealed a g ain in density (median=1.58 and 2.43 CADIA for the locally and the ful l-mouth treated groups, respectively). Differences in density were sig nificant, both between the nontreated and locally treated sites (p=0.0 26) and between the nontreated sites and the sites from the full mouth treated patients (p=0.002). The analysis of the soft tissues showed a similar pattern of changes in density to those seen in the bone defec t. At 2 months, there was a tendency for loss in density for the nontr eated group (median=-0.17 CADIA) that continued over the 6 month perio d (median=-0.31 CADIA). A significant increase in density was observed for the full-mouth treated sites (median=1.57 and 0.64 CADIA for the 2 and 6 months radiographs, respectively). A significant increase was also observed for the locally treated group when compared to the untre ated sites (median=0.13 and 0.10 CADIA for the 2 and 6 months radiogra phs, respectively). Comparing untreated sites with full-mouth treated sites, a significant difference was observed for CADIA measurements (p less-than 0.001). No significant difference was observed comparing lo cally treated and untreated sites (p=0.24). It was concluded that scal ing and root planing combined with TCF therapy can result in increased bone density and alveolar bone height. Full-mouth treatment seemed to result in more pronounced gains compared to local treatment. Untreate d sites continued to lose alveolar bone height and density. CADIA of s upracrestal soft tissue ROI paralleled the remodelling observed in bon e ROI. This is the first controlled study revealing that CADIA of soft tissue ROI in series of underexposed standardized radiographs may ren der additional valuable information on remodelling of periodontal tiss ues after therapy.