Hydroxyethyl Cellulose Promotes the Mucin Retention of Herbal Extracts Active against Streptococcus mutans.

Streptococcus mutans is considered a major cariogenic bacterium. Most anti-cariogenic dentifrices are limited by a short exposure time. The aim of the present study was to test the hypothesis that adding a mucoadhesive agent to the formulation may increase its bioavailability and efficacy. We tested the effect of adding hydroxyethyl cellulose (HEC) to an herbal extract solution containing lavender, echinacea, sage, and mastic gum, which have been previously shown to be effective against Streptococcus mutans. Mucin-coated wells were treated with four test solutions: saline, herbal extracts, herbal extracts with HEC, and chlorhexidine. The wells were incubated with Streptococcus mutans and studied for biofilm formation (Crystal violet assay), acid production (lactate assay), acid tolerance (ATPase assay), and exopolysaccharide (EPS) production using fluorescent microscopy. The results showed that the addition of HEC to the herbal extract solution caused a significant reduction in Streptococcus mutans biofilm formation, lactic acid production, and EPS quantity (p < 0.001). These results suggest that HEC may be a beneficial added excipient to herbal extracts in an anti-cariogenic formulation.

Effect of Sublethal Blue Light on Herbal Extract Activity Against Volatile Sulfide Compound Production by Fusobacterium nucleatum.

Previously, we have shown that sublethal exposure of blue light caused increased cell membrane permeability in Fusobacterium nucleatum. The aim of the present study was to test the effect of this exposure on the activity of Lavender, Sage, Echinacea and Mastic gum extracts against volatile sulfide compound (VSC) production by Fusobacterium nucleatum. Bacterial suspensions were pre-exposed to blue light (400-500 nm) bellow minimal inhibitory dosage (sub-MID). Exposed and nonexposed samples were inoculated into test tubes containing growth medium, filtered saliva with or without herbal extracts. Following incubation, test tubes were tested for malodor production (odor judge scores), VSC levels (OralChroma), salivary protein degradation (SDS-PAGE) and bacterial cell membrane damage (fluorescence microscopy). Results showed that sub-MID blue light exposure significantly increased the ability of Lavender and Echinacea to reduce VSC production by Fusobacterium nucleatum by more than 30%. These results suggest that sublethal blue light exposure may be useful to increase the efficacy of antimalodor agents.

Effect of High Intensity Blue Light on Fusobacterium nucleatum Membrane Integrity.

Oral malodour is considered to be caused mainly by the production of volatile sulfide compounds (VSC) by anaerobic gram-negative oral bacteria. Previous studies showed that these bacteria were susceptible to blue light phototoxicity mediated by the production of reactive oxygen species (ROS). In the present study, we tested the effect of blue light on the integrity Fusobacterium nucleatum's membrane, cellular proteins and DNA. Bacterial samples were exposed to high intensity blue light for 0, 70, 140 and 280 s (i.e. fluences of 0, 96, 192 and 384 J cm-2 , respectively). Following light exposure, bacterial samples were examined for membrane damage using fluorescence microscopy, intra-cellular protein analysis using electrophoresis (SDS-PAGE) and DNA fragmentation using ultra-filtration. Results showed that the increasing exposure of bacterial samples to blue light caused increased membrane permeability concomitant with a reduction in intra-cellular proteins and DNA fragments content. These results suggest that membrane damage is the main effect of high intensity blue light exposure on malodour producing bacteria.

Zinc enhances the phototoxic effect of blue light against malodour-producing bacteria in an experimental oral biofilm.

Oral malodour is thought to be caused mainly by the production of volatile sulfide compounds (VSCs) by anaerobic Gram-negative oral bacteria. Previous studies have shown that these bacteria are susceptible to blue light (400-500 nm wavelength). In the present study, we tested the effect of blue light in the presence of zinc, erythrosine B or both on malodour production in an experimental oral biofilm. Biofilms were exposed to a plasma-arc light source for 30, 60 and 120 s (equal to energy fluxes of 41, 82 and 164 J cm(-2), respectively) with or without the addition of zinc acetate, erythrosine B or both. After the light exposure, biofilm samples were examined for malodour production (by an odour judge) and VSC production (with a Halimeter), and VSC-producing bacteria were quantified using a microscopy-based sulfide assay (MSA) and in situ confocal laser scanning microscopy (CLSM). Results showed that exposing experimental oral biofilm to both blue light and zinc reduced malodour production, which coincided with a reduction in VSC-producing bacteria in the biofilm. These results suggest that zinc enhances the phototoxicity of blue light against malodour-producing bacteria.

The effect of short dental trauma lecture on knowledge of high-risk population: an intervention study of 336 young adults.

AIM: The purpose of this interventional study was to evaluate the effect of a short dental trauma lecture on knowledge of first-aid management of dental avulsion among high-risk population. METHODS: A total of 336 army recruits were randomly assigned to two groups. To evaluate the level of knowledge, we used a structured questionnaire, adapted from Andersson et al. (Dent Traumatol, 22, 2006, 57) and translated to Hebrew. The control group (n = 137) answered the questionnaire. The intervention group (n = 199) received a 60-min slides lecture by a (military) dental practitioner, regarding general concepts of body injuries, facial and oral injuries and practise first-aid management of these injuries. The intervention group filled the same questionnaire following this lecture. RESULTS: General knowledge of emergency treatment of injuries to other parts of the body was rather good for all participants; however, the level of knowledge was significantly higher in the intervention group (P < 0.05). General knowledge regarding tooth and avulsion was quite disappointing in the control group but was significantly higher in the intervention group (P < 0.001). The same was observed when interpreting the results regarding special knowledge of avulsion first-aid management: How to clean the tooth before replantation, extra-alveolar time and storage method and medium (P < 0.001). CONCLUSIONS: The present study revealed excellent results following a short dental trauma instruction lecture. As raising the public awareness on the subject of dealing with dental trauma is important for the prognosis of the tooth, this way of improving knowledge to high-risk populations should be further examined in long-term studies.

Prevention of dental trauma in a high-risk military population: the discrepancy between knowledge and willingness to comply.

Military fighters are at high risk for oral/tooth injuries. Our aim was to evaluate the knowledge and willingness to use preventive measures among this population to reduce oral trauma. A total of 336 fighters were randomly assigned to two groups. The control group answered a structured questionnaire, which included questions regarding: knowledge of the benefits of mouthguard use, past/current use, and willingness to use a mouthguard. The intervention group received a 60-minute dental trauma lecture, and responded to the same questionnaire. Significantly more subjects in the intervention group were familiar with the benefits of mouthguards compared to the control group, but there was no difference between the groups in their willingness to use mouthguards routinely. Discomfort and potential interference to sport performance were the most common reasons for rejection. It seems that a structured lecture is not sufficient for ensuring usage of mouthguards in a military population. Emphasis on motivation or mandating use may be required.