Comparison of Antibacterial Effect of Probiotic Yogurt and Xylitol-Containing Chewing Gum in Geriatric Patients: A Randomized Controlled Clinical Trial

Objectives

To evaluate the effect of probiotic bacteria in yogurt on Streptococcus mutans (MS) count, plaque adherence and salivary pH compared to xylitol-containing chewing gum in geriatric patients.

Materials and methods

Total number of 96 high caries risk geriatric patients were randomized into two equal groups (n=48). Group 1 (intervention group) received probiotic yogurt (Activia, Danone) once per day, and group 2 (control group) received xylitol chewing gum (Trident original) three times per day. The primary outcome was salivary Streptococcus mutans count and secondary outcomes were interdental plaque Streptococcus mutans count, salivary pH and bacterial adherence.

Results

For Streptococcus mutans count in saliva and plaque, a statistically significant reduction in the level of MS over all the examined follow up periods of the study in probiotic yogurt group as well as xylitol gum group was found. An intergroup comparison for salivary MS count showed statistically significant difference between the two materials in a two week and a three month period of time and there was no statistically significant difference between both materials at one month time period. Salivary pH results showed statistically significant increase in pH in both groups along the follow-up periods. Bacterial adherence results showed statistically significant reduction in both groups.

Conclusions

Probiotic yogurt is an effective antibacterial agent against salivary and plaque bacteria in geriatric patients.

Effect of a Self-Etch Adhesive Containing Nanobioglass on Postoperative Sensitivity of Posterior Composite Restorations - A Randomized Trial

BACKGROUND

Postoperative sensitivity is one of the major problems regarding posterior resin composite restorations that causes patient discomfort, maybe a reason for replacement of the restoration with an additional office time.

AIM

To evaluate the effect of the addition of a Nanobioglass to a self-etch adhesive on the reduction of post-operative sensitivity following composite restorations versus a self-etch adhesive that is free of Nanobioglass agent.

MATERIALS AND METHODS

Sixteen patients having class II carious lesions were included in the study. After cavity preparation, each tooth was randomised to one of the following restorative treatments. Teeth in the control group were restored using self-etch adhesive (OptiBond All-In-One, Kerr) that is free of nanobioglass agent, and nano-hybrid resin composite (Herculite Ultra, Kerr). Restoration of teeth in the experimental group was similar to the control except that a nanobioglass agent was added to the self-etch adhesive. Patients were contacted for evaluation of postoperative sensitivity at 1 day, 1 week, 1 month, and 3 months. Data were analyzed using friedmann test followed by fisher exact test.

RESULTS

The experimental group (self-etch adhesive containing nanobioglass) showed a significantly less postoperative sensitivity compared with the control group (Self-etch adhesive free of nanobioglass) at 1 day, and 1-week evaluation periods. While both groups did not possess any significant difference at 1 month, and 3 months periods.

CONCLUSION

The problem of postoperative sensitivity following resin composite restorations could be solved by the addition of bioglass nanoparticles into dental adhesives.

Microleakage and marginal gap formation of glass ionomer resin restorations

The purpose of this in vitro study was to compare microleakage and marginal gap formation of three light-cured glass ionomer cements (LCGI). Thirty non-carious human premolar teeth were used in this study. A Class V cavity was prepared in the buccal surface of each tooth. The teeth were randomly divided into three experimental groups of 10 teeth each and restored with three LCGI materials. The teeth in each group were processed for microleakage study using 5% methylene blue. Subsequently, each tooth was embedded in acrylic resin and sectioned longitudinally in a buccolingual direction. Examination of the specimens for dye penetration was done. Later, evaluation of marginal gap formation and analysis of adhesion mechanism were done using SEM. The results indicated that LCGI restorations placed in vitro without thermocycling did not consistently prevent microleakage. Vari Glass VLC showed the least leakage. There was no significant difference in the microleakage between the occlusal and gingival margins. Marginal gap formation was found only in one LCGI material. Generally, the presence of a clearly identified ion-exchange layer was not found.