You will be provided with the titles and abstracts of a collection of medical RCT reports studying a clinical question -- for instance, the efficacy of an intervention on some medical outcome. Please write a few sentences synthesizing the findings of these reports, which could serve as a conclusion section for a systematic review article. Your response should not include any other text. The RCT reports are below.



Title 1:
Comparison of two popular methods for removal and killing of bacteria from dentures.
Abstract 1:
A study was undertaken to compare the efficacy of a soaking solution (Efferdent Extra-Strength Denture Cleanser Tablets) to mechanical cleaning with a denture paste (Advanced Formula Dentu-Creme Denture Cleaning Paste) to remove and kill plaque bacteria from removable dentures. The study was conducted in a randomized, four-way crossover fashion with 18 subjects. At each clinic visit, subjects were randomized to one of four treatment regimens: 1) no treatment; 2) brushing with denture paste; 3) soaking in Efferdent; 4) brushing followed by soaking in Efferdent. Microbiological sampling for plaque bacteria was made before and after each treatment. Aliquot samples of 10-fold serial dilutions were plated on supplemented Schaedler Agar (for total anaerobes) and on CVE agar (for fusobacteria). Analysis of covariance was performed on the log10 transformed scores at posttreatment using the pre-treatment scores as covariates. Significant treatment effects were: F(3,41) = 81.60, p less than 0.001 for anaerobes and F(3,50) = 104.38, p less than 0.001 for fusobacteria. Pairwise comparisons using Tukey hsd post hoc tests showed that for total anaerobes, treatments 1 and 2 yielded higher scores than treatments 3 and 4. For fusobacteria, treatment 1 greater than 2 greater than 3 or 4; no difference between treatments 3 and 4. The results demonstrated the superior performance of Efferdent over Dentu-Creme.


Title 2:
Reduction of formation of denture plaque by a protease (Alcalase).
Abstract 2:
The efficacy of a protease preparation (Alcalase, Novo, Denmark) in preventing accumulation of plaque on the fitting surface of complete upper dentures was examined in a double-blind study. Seventeen denture wearers with clinically healthy oral mucosae participated in the study. The protease was dispensed in dissolvent tablets containing 15, 30, 60, 100, 300, 500, or 1000 mg of the enzyme. Enzyme tablets or placebo tablets were dissolved in 150 ml water at 50 degrees C, and the dentures were soaked once daily for 15 min. Denture soaking was performed with or without brushing. The study consisted of 14 1-week periods. At the start of each period the dentures were cleaned by brushing until they showed no visible plaque after staining. At the end of each period plaque was stained and the dentures were photographed. The photographs were projected, and the percentage area of the fitting surface showing plaque deposits was scored with 10% intervals. Statistical analysis showed that there was a significant reduction of plaque scores with increasing enzyme concentration. The most marked reduction in plaque formation was seen when mechanical cleansing was combined with immersion in a 500-mg enzyme solution. At a concentration of 300 mg (or more) the enzyme immersion was as efficient as mechanical cleansing in preventing denture plaque accumulation.


Title 3:
A 3-months' study of enzymes as denture cleansers.
Abstract 3:
It was the purpose of the study to test the efficacy of dissolvent tablets containing mutanase and protease in removing denture plaque. The study group consisted of forty institutionalized geriatric denture wearers, who were assigned randomly into an enzyme group and a placebo group. Enzyme tablets and placebo for denture soaking were administered by the nurses. The dentures were immersed for 15 min once daily for three months. The amount of denture plaque, the clinical condition of the palatal mucosa, and the concentration of yeasts and bacteria in mucosal and denture smears were recorded before, during, and after the experimental period. The study was designed and carried out as a double-blind study. After denture soaking for six weeks a significant reduction of the amount of denture plaque and improvement of the clinical condition of the palatal mucosa was recorded. After denture soaking for twelve weeks the conditions had improved further when comparing the enzyme group with the placebo group.


Title 4:
Sanitization of dentures by several denture hygiene methods.
Abstract 4:
Denture sanitization is an important element in the treatment of denture stomatitis and should be emphasized in instructions to patients. A two-part study was designed to compare the efficacy of eight denture-cleaning methods in removing and/or killing aerobes, anaerobes, and yeasts on dentures. Part I tested the effectiveness of the cleaners on a pure yeast culture of C. albicans. Part II tested the various denture sanitization techniques under actual clinical conditions. The following conclusions were made from the information obtained in this study: Miller's and Kleenite were the most effective sanitizing agents. Brushing the denture with soap and water and soaking the denture in the cleaner Mersene were effective to a lesser degree. Although Clorox and Calgon was effective at killing yeast under in vitro conditions, it was not effective under clinical conditions. The other denture cleaners were not found to be effective under the clinical conditions of this study for the removal and/or killing of any of the three microorganism groups cultured. In the past, the function of denture cleaners has been to remove deposits and stains from dentures. With the present knowledge of the role of microorganisms in the etiology of denture stomatitis, more emphasis should be placed on the ability of denture cleaners to sanitize dentures.


Title 5:
Assessment of plaque prevention on dentures using an experimental cleanser.
Abstract 5:
Adequate plaque control is essential for the maintenance of a healthy oral mucosa. Denture cleansers are a popular method used by denture wearers for cleaning. The clinical effectiveness of a new cleanser in tablet form has not been tested in vivo. Methods used for the in vivo assessment of denture cleanser effectiveness are often not standardized.
                The aims of this in vivo study were to develop a new method for assessing plaque levels on dentures by using digital imaging and to use this methodology, together with a validated visual scoring method, to evaluate plaque buildup on dentures.
                Thirty-five subjects were randomized to 1 of 2 treatment groups: (1) dentures soaked in a new cleanser, or (2) dentures soaked in water. The treatment period lasted 14 days. Plaque was assessed at baseline and on days 2 and 14 by using digital image analysis and a visual scoring technique. Results were analyzed with ANOVA at the 95% confidence interval.
                The new cleanser showed a statistically significant reduction in mean visual plaque of 51% at day 2 (P = 0.0002) and 42% (P = 0.0014) at day 14 compared with water. Similar results were seen with digital imaging.
                The new denture cleanser proved to be effective at preventing plaque accumulation on dentures. The analysis of digital images gave similar results as the visual scoring method.


Title 6:
Denture cleansing: a comparison of two methods.
Abstract 6:
A paste brushing method (Complete) and soaking in either of two denture cleanser tablet solutions (Efferdent or Polident) were compared for denture cleansing effectiveness as measured by plaque level. The 12-week product use period with weekly evaluations allowed an assessment of plaque reaccumulation on the denture surface as well as the effect of a single cleansing event and the contribution of bleaching to the total plaque-cleansing activity. The paste/brushing method was consistently the more effective procedure for removal of denture plaque. However, the bleaching effects of the effervescent tablets could be useful in an overall denture hygiene program.
There is a lack of evidence about the comparative effectiveness of the different denture cleaning methods considered in this review. Few well designed RCTs were found. Future research should focus on comparisons between mechanical and chemical methods; the assessment of the association of methods, primary variables and costs should also receive future attention.