Modulation of clinical expression of plaque-induced gingivitis. II. Identification of "high-responder" and "low-responder" subjects.

AIM: The aims of this study were to validate a randomized, split-mouth, localized experimental gingivitis model and to identify subjects with different gingivitis susceptibility. MATERIAL AND METHODS: In each of 96 healthy subjects, one maxillary quadrant was randomly assigned as "test" (experimental gingivitis) and the contralateral quadrant as "control". Plaque index (PlI), gingival index (GI), gingival crevicular fluid volume (GCF), and angulated bleeding score (AngBS) were recorded in both quadrants at days 0, 7, 14, and 21. Cumulative plaque exposure (CPE), i.e. PlI over time, was calculated. Day-21 GCF was standardized according to CPE, and residuals of GCF on CPE were calculated. Two subpopulations were then defined, based on upper and lower quartiles of GCF-residual distribution and were, respectively, identified as "high-responder" (HR; n=24) and "low-responder" (LR; n=24). RESULTS: At test quadrants, all parameters significantly increased throughout the trial, while in control quadrants, PlI, GI, and AngBS remained low. Significant differences were noted between test and control quadrants on days 7, 14, and 21 for all parameters. Significant increases in GI, AngBS, and GCF were observed in test quadrants over the course of the study in both HR and LR groups. Significant differences were noted between HR and LR groups for all gingivitis parameters on day 21 in test quadrants, without any significant differences in PlI or CPE between the groups. CONCLUSIONS: We identified two subpopulations characterized by significant differences in clinical parameters of plaque-induced gingival inflammation, despite similar amounts of plaque deposits and plaque accumulation rates.

Modulation of clinical expression of plaque-induced gingivitis. III. Response of "high responders" and "low responders" to therapy.

AIM: The aim of the present study was to characterize the subject-based clinical behavior of the gingiva in response to a tooth-cleaning regimen in two subpopulations, "high-responder" (HR) and "low-responder" (LR) groups, presenting a different inflammatory response to plaque accumulation. MATERIAL AND METHODS: The study population comprised of 96 systemically and periodontally healthy subjects, 46 males and 50 females, non-smokers, enrolled in an experimental gingivitis trial. At completion of the experimental gingivitis period (day 21), all subjects were prescribed the same 21-day treatment regimen of amine/stannous fluoride (AmF/SnF(2))-containing toothpaste and mouthrinse. Plaque index (PlI), gingival index (GI), gingival crevicular fluid volume (GCF), and angulated bleeding score (AngBS) were recorded on three selected teeth. Treatment efficacy was evaluated in the overall population as well as in HR and LR groups, separately. RESULTS: A statistically significant decrease of PlI was observed after treatment (p<0.001), with PlI reversing to baseline levels. Changes in PlI revealed the same trend in both HR and LR groups, without differences between groups. Treatment also resulted in a significant decrease of all gingivitis parameters (p<0.001 for all comparisons). After treatment, GI, AngBS, and GCF were comparable with baseline condition. However, when the two groups were compared, day 42-GCF was significantly higher in the HR group than the LR group. CONCLUSIONS: A treatment regimen based on mechanical plaque control supplemented with AmF/SnF(2)-containing toothpaste and mouthrinse is effective in reducing plaque accumulation and re-establishing healthy gingival conditions after experimentally induced gingivitis, even in subjects with different inflammatory response to plaque accumulation.

Supracrestal soft tissue preservation with enamel matrix proteins in treatment of deep intrabony defects.

BACKGROUND/AIMS: The purpose of the present study was to investigate the effectiveness of a regenerative procedure based on supracrestal soft tissue preservation in association with enamel matrix proteins (EMP) in the treatment of deep intrabony defects. METHODS: The subjects included 35 consecutively treated patients, 23 females and 12 males, aged 28-61 years, 11 of whom were smokers. Patients presented with at least one intrabony defect with probing pocket depth > or = 6 mm and a radiographic depth of the defect > or = 4 mm at the initial visit. Immediately before surgery and 9-12 months after surgery, Local Plaque Score (LPS), Local Bleeding Score (LBS), probing pocket depth (PPD), clinical attachment level (CAL), gingival recession (REC), and radiographic depth of the defect (DEPTH) were recorded. RESULTS: Thirty-one (88.6%) defects were LPS-negative presurgery, while 29 (82.9%) defects presented with no plaque postsurgery. The prevalence of LBS-positive defects shifted from 94.3% presurgery to 8.4% postsurgery (p < 0.0000). PPD was 8.9 mm before surgery, and decreased to 3.5 mm postsurgery (p < 0.0000). CAL varied from 10.1 mm presurgery to 5.4 mm postsurgery (p < 0.0000), with an average improvement (gain) of 4.7 +/- 1.7 mm. Twenty-six (74.3%) defects presented a gain of least 4 mm. Regression analysis showed a positive correlation between CAL gain as a dependent variable, and presurgery PPD and amount of supracrestal soft tissues as predictors. DEPTH improvement (gain) was 3.9 +/- 1.8 mm, which represented 65% of defect fill. Twenty (57.1%) defects presented a DEPTH gain of at least 4 mm. DEPTH gain was significantly correlated to presurgery PPD (p < 0.000). No significant differences were found between smokers and non-smokers in terms of CAL and DEPTH gain. CONCLUSIONS: Results from the present study indicated that the regenerative procedure based on supracrestal soft tissue preservation and EMP application leads to clinically and statistically significant improvement of hard and soft tissue conditions of deep intrabony defects.