Comparison of irrigation to floss as an adjunct to tooth brushing: effect on bleeding, gingivitis, and supragingival plaque.

OBJECTIVE: The purpose of this twenty-eight day, randomized, single-blind clinical trial was to assess the efficacy of the addition of daily oral irrigation to both power and manual tooth brushing, compared to a traditional regimen of manual tooth brushing and flossing, to determine which regimen had the greatest effect on the reduction of gingival bleeding, gingivitis, and supragingival plaque. METHODOLOGY: The study was designed for a total of 105 subjects to participate in a twenty-eight day trial, with 35 subjects randomly assigned to one of three groups: Group 1-manual toothbrush and floss; Group 2-manual toothbrush and dental water jet; and Group 3-sonic toothbrush and dental water jet. All subjects received written and verbal instructions for using their regimens. Subjects were asked to brush for a timed two minutes, twice per day, with the brush and the dentifrice provided, and to refrain from using any additional oral hygiene aids. Subjects using the dental water jet were instructed to use the water jet on a medium setting, irrigating once per day with 500 ml of luke warm water. Subjects using the dental floss were instructed to use the floss once daily. Subjects were examined by two calibrated examiners, and data were collected at baseline (BSL), 14 days (D14), and 28 days (D28). Subjects were asked to abstain from any oral hygiene for 12 hours prior to each study visit. Subjects were scored using the Carter and Barnes Bleeding Index, Löe and Silness Gingival Index, and the Proximal/Marginal Plaque Index. Mean scores on the three indices for the three groups were used for statistical analysis at each time point. Additionally, the means were used for comparisons as change from baseline and percent change from baseline at D14 and D28. The significance of percentage change in each index from baseline to D14 and D28 was evaluated using a one-tailed t-test. Significant differences are reported at alpha < or = 0.05 for these planned group comparisons. RESULTS: Thirty-one subjects in Group 1, 32 subjects in Group 2, and 32 subjects in Group 3 completed the study. Bleeding Index: Groups 2 and 3, the irrigation groups, were statistically significantly more effective than Group 1 in reducing the bleeding index at D14 and D28, whether measured by mean reduction or percentage reduction. Gingival Index: At D14, both irrigation groups demonstrated a statistically significantly greater reduction in the gingival index compared to brushing and flossing for the facial surfaces. There was no significant difference between groups for the lingual surface at D14. At D28 there was a significant difference between Groups 1 and 2 for both the facial and lingual surfaces. Plaque Index: There was one significant difference between groups for the plaque index measured on the lingual surfaces. The manual toothbrush and floss were less effective than the sonic toothbrush and irrigation. Group 3 was also significantly better than Group 1 in reducing the plaque index on the facial surfaces at both D14 and D28. On plaque percentage reduction on the facial surface, Group 2 was significantly better than Group 1 at D14. There was no statistical difference between Group 1 and Group 2 at D28. CONCLUSION: The results of this clinical trial indicate that when combined with manual or sonic tooth brushing, oral irrigation is an effective alternative to manual tooth brushing and dental floss for reducing bleeding, gingival inflammation, and plaque removal.

A comparison of a waterpik dual-motor powered toothbrush and a manual toothbrush in affecting interproximal bleeding reduction and dental biofilm accumulation.

OBJECTIVE: This single-blind, 21-day clinical study was designed to compare the effectiveness of a dual-motor powered toothbrush (SynchroSonic) and a manual toothbrush in affecting interproximal bleeding reduction and dental biofilm accumulation in a cohort of 70 subjects. METHODOLOGY: After baseline evaluations of soft tissue trauma, dental biofilm and interproximal bleeding, subjects were randomly assigned to one of the two experimental groups, given toothbrushing instructions and had their teeth cleaned. At 21 days, the clinical parameters were again evaluated. RESULTS: In the powered toothbrush group, there were 37 subjects at baseline and 36 subjects at follow-up. In the manual toothbrush group, there were 34 subjects at baseline and 33 subjects at follow-up. In the powered toothbrush group, the mean biofilm index fell from 3.46 to 3.12; a 9.7% reduction. In the manual toothbrush group, the mean biofilm index fell from 3.51 to 3.30; a 5.4% reduction. The powered toothbrush group showed significantly greater biofilm reduction (9.7% vs. 5.4%, p = 0.043). In the powered toothbrush group, the mean gingival bleeding index fell from 0.66 to 0.44; a 32% reduction. In the manual toothbrush group, the mean gingival bleeding index fell from 0.66 to 0.53; a 20% reduction. The powered toothbrush group showed significantly greater gingival bleeding reduction (32% vs. 20%, p = 0.02). CONCLUSION: The results demonstrated that both the manual toothbrush and the SynchroSonic powered toothbrush were safe, with no evidence of clinically significant hard or soft tissue abrasion observed. Additionally, the powered toothbrush was more effective in reducing biofilm and gingival bleeding than the manual toothbrush.

Impact of increased occlusal contact, interleukin-1 genotype, and periodontitis severity on gingival crevicular fluid IL-1beta levels.

BACKGROUND: The study of occlusal therapy in humans with periodontitis is problematic due to potential irreversible bone loss in control subjects. The hypothesis of this pilot investigation was that increased interocclusal contact initiated by short-term occlusal splint disuse would increase tooth mobility and the bone-resorptive cytokine interleukin (IL)-1beta in gingival crevicular fluid (GCF), comparable to IL-1-positive genotype and increased periodontitis severity. METHODS: Nineteen non-smoking chronic periodontitis patients using nocturnal occlusal splints and undergoing periodontal maintenance in a private practice were evaluated at five time points: 24 hours after continuous splint use; 1, 2, and 3 days after no occlusal splint use; and 14 days after resumption of customary nighttime splint use. Subjects were evaluated to confirm that the plaque index and gingival index were < or = 1.0, and to categorize past periodontitis (moderate or severe) and IL-1 genotype (1A +4845 plus IL-1B +3954). Test sites on two anterior teeth vulnerable to occlusal trauma were sampled for mobility, GCF IL-1beta, and IL-1 receptor antagonist (ra). RESULTS: Tooth mobility remained low during the 3-day period when patients were not wearing their occlusal appliance. GCF IL-1beta decreased after not wearing the appliances (P = 0.016), especially at 48 hours. At this time, genotype-positive subjects had higher levels of GCF IL-1beta/IL-1ra than genotype-negative subjects (P = 0.045), and patients who had experienced severe periodontitis had higher IL-1beta levels than moderate periodontitis subjects (P = 0.004). CONCLUSIONS: These findings suggest that short-term discontinuation of occlusal splint therapy in non-smoking periodontitis patients undergoing periodontal maintenance does not result in potential signs of early occlusal trauma (increasing mobility or GCF IL-1beta). Longer-term studies may be needed to determine appropriate therapy applications for periodontitis-susceptible patients with definable occlusal discrepancies and/or parafunction.

Effects of local cooling rate and processing variables on leucite in dental porcelain.

PURPOSE: This research determined whether there is a measurable effect of local geometry factors on leucite content of dental porcelain in fixed partial dentures (FPD). MATERIALS AND METHODS: Four-unit FPD frameworks (n = 36) were fabricated using a nickel-chromium alloy (Rexillium III). Body porcelain (Crystar, shade A2) was applied in one increment and subjected to two simulated body firings, followed by a simulated glaze firing to achieve a thickness of 1.5 to 2.0 mm. The completed FPD specimens were randomly assigned to three groups of 12 specimens each: (1) simulated post-soldering, (2) multiple firing, and (3) control. The FPDs from each test group were sectioned into individual units: canine retainer, premolar pontic, molar pontic, and molar retainer. The porcelain was removed from each unit, and the leucite content was measured via quantitative x-ray diffraction. RESULTS: Porcelain cracking indicated that the soldering simulation had successfully reproduced conditions in the dental laboratory that result in porcelain cracking during soldering. The leucite content was not significantly different between the retainer and pontic units for either the soldering simulation or control FPDs, although the canine retainer units did have a slightly lower leucite content than the pooled values of the other units. Comparison of the pooled data for the three groups indicated statistically significant differences among the leucite contents. CONCLUSION: Compared to the control, the simulated post-soldering procedure produced a significant increase in leucite, and the multiple firing group exhibited a significant decrease in leucite. Increases in leucite weight fraction during post-soldering operations-and the larger thermally induced stresses that accompany these leucite increases-are responsible for the cracking that occurs.

A Comparison of the Efficacy of 2 Powered Accumulation, Gingivitis, and Gingival Bleeding Toothbrushes in Affecting Plaque.

BACKGROUND: The purpose of this 30-day blinded, parallel-design study was to compare the effect of 2 powered toothbrushes, the Rowenta MH700 and the Braun Plak Control Ultra, on reducing plaque accumulation, gingivitis, and gingival bleeding in a cohort of 60 healthy adults. METHODS: After baseline evaluation of plaque, gingivitis, and gingival bleeding, subjects were randomly assigned to one of the experimental groups, provided written and verbal toothbrushing instructions, and had their teeth polished. At 2 weeks (follow-up 1) and 4 weeks (follow-up 2) all clinical parameters were again evaluated. RESULTS: The Braun group demonstrated a nearly significant reduction in gingival index (Gl) and a significant reduction in GI at follow-up 2. The Rowenta group demonstrated significant reductions in GI, plaque index (PI), and bleeding index (GBI) at both follow-up 1 and 2 examinations. At follow-up 1, the Braun group demonstrated a nearly significant reduction in GI, a significant reduction in PI, and a non-significant reduction in GBI. At follow-up 2, the Braun group demonstrated a significant reduction in GBI, but not a significant reduction in PI. The reduction in GI for the Rowenta group was significantly greater (P values of 0.0001 and 0.0001, respectively) than that demonstrated in the Braun group. However, the Rowenta group did not demonstrate a significantly greater reduction in PI (P values of 0.7135 and 0.3184 for follow-up 1 and follow-up 2, respectively) or GBI than the Braun group at either examination (P values of 0.0663 and 0.3397 for followup 1 and 2, respectively). CONCLUSIONS: The results of this study support the findings of numerous other studies that powered toothbrushes have great potential to remove plaque and improve gingival health and that the improvement can be demonstrated in a relatively short period of time. J Periodontol 1999;70:840-847.

Simulation study of a panel of reliability indicators applied to paired measurements.

Reliability is a subject of continuing discussion in biomedial specialty areas, including physical anthropology and nutritional epidemiology. The purpose of this study was to explore techniques of detecting differences between two evaluators or methods. A field study in which anthropometric dimensions would be taken by two independent evaluators on each participant in a study group was simulated. A panel of reliability indicators was applied across a broad range of parameters using simulation, and then the panel was applied to field anthropometric data. The panel consisted of the intraclass correlation coefficient (ICC), paired t-test, a simultaneous test of evaluator means and variances, technical error of measurement, mean absolute difference, and mean difference. The simultaneous test for equal evaluator means and variances uses regression to model paired differences versus paired sums. The simulation demonstrated general properties of the reliability indicators across many conditions of population variance, measurer bias, and measurer error variance. High values of ICC often exist in cases in which the measurers are different. The simultaneous test is thus a powerful method for detecting measurer differences, especially when combined with the paired t-test. However, a single reliability indicator that is sufficient to determine all measurer inconsistencies was not identified. The field study and the simulation permitted the development of a logical approach to determining the source and magnitude of measurer differences using the panel of reliability indicators. © 1994 Wiley-Liss, Inc.

Precision of recumbent anthropometry.

In some studies recumbent anthropometric measures are more appropriate than standing measures. There is little published information, however, on the precision of recumbent measures. To estimate the interobserver precision of recumbent anthropometry, 22 men and 29 women volunteers 35-64 years of age were each measured on the same day by four trained nurses previously inexperienced in anthropometry. Fourteen recumbent measurements were taken, including abdominal sagittal diameter measured with a new type of caliper. The nurses also measured standing waist and hip girths. Various indicators of interobserver precision were estimated including the intraclass correlation coefficient (ICC). The ICC ranged from 98.5% for calf girth to 56.2% for the suprailiac skinfold in men, while it ranged from 95.8% for upper arm girth to 67.0% for the suprailiac skinfold in women. The abdominal sagittal diameter measurement had very high precision as estimated by the ICC in both men and women, 95.8% and 96.3%, respectively. Recumbent waist girth was, on average, only 0.3 cm larger than standing girth. In contrast, recumbent hip girth was 3.8 cm smaller than standing girth. These findings suggest that studies using recumbent anthropometry can achieve levels of precision similar to those obtained with standing anthropometry. For both sexes, however, the suprailiac skinfold appears to have much lower precision in the recumbent than in the standing position. In addition, prevalence estimates of abdominal obesity derived from the ratio of waist-to-hip girths will be higher in studies using recumbent anthropometry than in studies using standing anthropometry. © 1993 Wiley-Liss, Inc.