Longitudinal study of the influence of removable partial denture and chemical control on the levels of Streptococcus mutans in saliva

Abstract

Some studies have evaluated the salivary levels of mutans streptococci (MS) in removable partial denture (RPD) users. Saliva samples (2.0 mL) were obtained from 31 patients in six periods: (T0): immediately before installation of RPD; (T8): 8 days after T0; (T48): 48 days after T0; (T92): 92 days after T0; (T140): 140 days after T0 and (T189): 189 days after T0. The samples were vortexed and serially diluted from 10(-1) to 10(-6) in 0.05 m phosphate buffer (pH 7.4). From each dilution, 0.025 mL was plated on Mitis Salivarius Bacitracin (MSB). The plates were incubated in 5% CO2 at 37 degrees C for 72 h. There was an increase (t-test, P < 0.05) in the number of MS between periods T0 and T48 (mean/s.d., CFU mL(-1) of saliva): T0: 2.26/4.43 x 10(6) and T48: 0.47/1.48 x 10(8). After this, intensive treatment with CHX was accomplished in 29 patients. Saliva samples were obtained after treatment in four periods: (T24 h): 24 h after T0; (T14): 14 days after T24 h; (T28): 28 days after T24 h, and (T63): 63 days after T24 h. The number of MS in saliva did not decrease (t-test, P > 0.05). A new CHX formulation was applied in 15 patients. Saliva samples were obtained in periods: (T0): before new CHX application; (T24 h): 24 h after T0 and (T82): 82 days after T0. The new CHX reduced MS levels in saliva: (mean/s.d., CFU mL(-1) of saliva): T0: 6.64/8.47 x 10(6) and T24 h: 3.2/4.27 x 10(5) (sign rank, P < 0.05). In conclusion, there was a significant increase in the number of MS in saliva after the installation of RPD. The intensive treatment with a properly formulated CHX was effective in the reduction of MS, between 24 h and 82 days after its application.

The effect of different formulations of chlorhexidine in reducing levels of mutans streptococci in the oral cavity: A systematic review of the literature

“…However, there was a large between-individual variation in time of MS recolonization. Similar results were recorded by Rocha et al 39 With this variability in treatment response in mind, Wallman et al 42 devised individualized treatment plans for patients with an initial MS count > 5.0 Â 10 5 CFU/ml of saliva and a high number of restored teeth. Treatment effects were monitored for 12 weeks, with treatment repeated from 3 to 9 times in order to hold MS values below the originally detected levels.…”

“…32,33 CHX gel at 0.2%, 0.5%, and 1% is applied with a toothbrush, 30,31,34 while 1% and 5% gels are applied through professional prophylaxis 35 and with the aid of individual trays. [36][37][38][39] Toothbrush application of 0.2% and 0.5% CHX gel did not cause any significant decrease in MS levels as compared to a placebo gel. 30,31 Both studies showed a decrease in these microorganisms in both test and control group.…”

Association of removable partial denture use with oral and systemic health

“…47 In longitudinal studies, significantly elevated salivary counts of mutans streptococci were found between 4 and 6 months after insertion of RPDs compared with baseline. 48,49 Together, the above studies indicate that mutans streptococci benefit from the introduction of RPDs into the mouth. It is possible that these organisms proliferate on the denture materials themselves; alternatively, the presence of novel sheltered sites may be responsible for their increased growth.…”

Effect of Chlorhexidine Gel in Mentally Handicapped Children highly Infected with Streptococcus Mutans

“…Several factors can influence the re-colonization time of SM in individuals treated with chlorhexidine gel, including the number of restored tooth surfaces and retaining sites, as well as the amount of sucrose consumed daily by each volunteer [12,16,17]. In order to limit the effect of these factors on the re-colonization time of SM, restorative treatment of all children was made before the start of the experiment, and children and parents or guardians were advised to reduce sucrose consumption during the experiment period.…”

“…Sterile test tubes were used for saliva collection, containing ten glass beads to facilitate homogenization in tube shaker (Vortex). Before processing, the tubes were kept on crushed ice [16].…”