Gingival bleeding after chlorhexidine mouthrinses

Effects of Hydrogen-rich Water on Cariogenic Bacteria

Context

Some kinds of electrolysed water have been reported to exhibit antioxidant and bactericidal activity. However, studies on the effect of electrolysed hydrogen-rich water (EHW) with a neutral pH on cariogenic bacteria are limited.

Aim

This study aimed to evaluate the feasibility of using EHW as a mouthwash by examining its various effects on cariogenic bacteria.

Materials and Methods

To test the bactericidal and anti-biofilm formation effects of EHW on Streptococcus mutans and Streptococcus sobrinus, bacterial growth curves, colony-forming unit (CFU) counts, and crystal violet staining of biofilms were examined after exposing the bacterial pellets to EHW or tap water as a control for one minute. In addition, the expressions of glucosyltransferase and glucan-binding proteins encoding genes were examined using real-time PCR.

Results

Bacterial growth and biofilm formation were inhibited, and the number of CFUs was significantly reduced in the EHW group compared to the control group. The expression of genes encoding glucosyltransferases (gtfB, gtfC, and gtfI) and glucan-binding proteins (gbpC and dblB) were also decreased in the EHW group compared to the control.

Conclusions

Exposing cariogenic bacteria to EHW at neutral pH for one minute can effectively inhibit bacterial growth and biofilm formation in vitro, suggesting that EHW is a promising mouthwash.

Tooth marker of ecological abnormality: The interpretation of stress in extinct mega herbivores (proboscideans) of the Siwaliks of Pakistan

Climate affects living ecosystems and defines species physiology. Climate change causes certain stress on animals, recorded as Enamel Hypoplasia (EH). Proboscideans, the mega herbivores, were extensively represented in the Siwaliks of Pakistan between the Middle Miocene to Pleistocene (~15.99-~0.6 Ma). This study was carried out on 15 species from 9 genera and 4 families using 319 teeth from 266 individual quarries. Our results revealed that 20.06% (64/319) of teeth were infected by EH. Family Deinotheriidae faced higher stress during the terminal of the Middle Miocene (EH 25%). Dental characters of deinotheres indicated that this family preferred soft vegetation like C3 plants and failed to survive in grassland ecology at the onset of the Late Miocene (~10-9 Ma). Gomphotheriidae (EH 21.05%) and Stegodontidae (EH 23.40%) survived through warm and dry climatic conditions of the Late Miocene, but could not survive the cool and dry climate of Plio-Pleistocene where grasslands were abundant with less browsing activity. Family Elephantidae (EH 8.47%) was successful in drier conditions and utilized the exclusive C4 diet in open grasslands as efficient grazers, indicated by their tooth morphology. Elephantids were dominant of the proboscideans in open grassland and drier climate during Plio-Pleistocene in the Indian subcontinent. We assume that change in the Siwalik palaeoenvironment was governed by a microclimate.

Inhibition of streptococcal biofilm by hydrogen water

OBJECTIVES

The accumulation of oral bacterial biofilm is the main etiological factor of oral diseases. Recently, electrolyzed hydrogen-rich water (H-water) has been shown to act as an effective antioxidant by reducing oxidative stress. In addition to this general health benefit, H-water has antibacterial activity for disease-associated oral bacteria. However, little is known about the effect of H-water on oral bacterial biofilm. The objective of this study was to confirm the effect of H-water on streptococcal biofilm formation.

METHODS

In vitro streptococcal biofilm was quantified using crystal violet staining after culture on a polystyrene plate. The effect of H-water on the expression of genes involved in insoluble glucan synthesis and glucan binding, which are critical steps for oral biofilm formation, was evaluated in MS. In addition, we compared the number of salivary streptococci after oral rinse with H-water and that with control tap water. Salivary streptococci were quantified by counting viable colonies on Mitis Salivarius agar-bacitracin.

RESULTS

Our data showed that H-water caused a significant decrease in in vitro streptococcal biofilm formation. The expression level of the mRNA of glucosyltransferases (gtfB, gtfc, and gtfI) and glucan-binding proteins (gbpC, dblB) were decreased remarkably in MS after H-water exposure for 60s. Furthermore, oral rinse with H-water for 1 week led to significantly fewer salivary streptococci than did that with control tap water.

CONCLUSIONS

Our data suggest that oral rinse with H-water would be helpful in treating dental biofilm-dependent diseases with ease and efficiency.

Treatment of multiple recession-type defects in patients with esthetic demands

BACKGROUND

When multiple recession defects affecting adjacent teeth in esthetic areas of the mouth are present, patient-related considerations suggest the selection of surgical techniques that allow all gingival defects to be simultaneously corrected with the soft tissue close to the defects themselves. The aim of the present study was to evaluate, with respect to root coverage, the effectiveness of a new surgical approach to the coronally advanced flap procedure for the treatment of multiple recession defects in patients with esthetic demands.

METHODS

Twenty-two young systemically and periodontally healthy subjects with at least 2 recession-type defects affecting adjacent teeth in esthetic areas of the mouth were enrolled in the study. All recessions were Miller Class I or II. In each patient, all present recessions were treated at the same time with a modification of the coronally advanced flap technique. The clinical re-evaluation was made 1 year after the surgery.

RESULTS

A total of 73 recessions (mean recession depth 2.8 mm) were treated; mean number of gingival recessions in each subject was 3.4. At the 1-year examination, on average, 97% of the root surface was covered with soft tissue and 64 defects (88%) showed complete root coverage. Complete root coverage in all recessions was achieved in 16 out of 22 patients (73%), and no statistically significant relationship was found between the root coverage results and the number of recession defects treated in each patient. A statistically significant increase of keratinized tissue (0.6 mm) was observed after 1 year; this increase was inversely correlated (P <0.001) with the amount of presurgical keratinized tissue. The multiple regression model showed that the final result, in terms of root coverage, was significantly affected by the initial recession depth and by the amount of presurgical keratinized tissue. Greater reductions in recession depth were observed in the cases with worse initial conditions and with lesser amount of keratinized tissue apical to the recession defect.

CONCLUSIONS

The results of the present study demonstrated that the proposed surgical technique was very effective for the treatment of multiple gingival recessions affecting teeth in esthetic areas of the mouth and that these successful root coverage results could be achieved irrespective to both the number of recessions simultaneously treated during the surgical intervention and the presence, before surgery, of a minimal amount of keratinized tissue apical to the defects.

Gingival and mucosal reactions after intensive chlorhexidine gel treatment with or without oral hygiene measures

The aim of this study was to elucidate whether soft tissue reactions during chlorhexidine (CHX) treatment might be associated with meticulous oral hygiene measures. A commercially available 1% chlorhexidine digluconate gel (Hibitane Dental Gel) was applied in a custom tray for the mandibular arch, 10 min daily, for 14 days. A split mouth approach was used to allow evaluation of the effect of oral hygiene measures with toothbrush, toothpaste, and dental floss on one side of the arch. During the treatment period, 8 out of 12 subjects developed gingival and/or mucosal reactions appearing as white patches or ulcerations. Both the gingival reactions on the buccal marginal gingiva and the mucosal reactions near the margin of the custom tray occurred only when the gel treatment was combined with meticulous oral hygiene measures. The white patches, which could easily be detached, leaving ulcerated areas, consisted entirely of stratified squamous epithelium. The findings suggest that intensive treatment with chlorhexidine gel, in individually fitted custom trays, combined with meticulous oral hygiene measures may induce toxic effects on the surface layers of the gingiva and mucosa.

Delayed and immediate-type hypersensitivity to chlorhexidine

A case with both contact urticaria and delayed-type contact allergy to chlorhexidine is presented. A review of the literature on hypersensitivity reactions of delayed and immediate type to this compound is given.

A review of the literature on use of chlorhexidine in dentistry

In addition to its plaque-inhibiting effect, chlorhexidine possesses other properties beneficial for use in dentistry. These effects are outlined, and specific recommendations are given regarding chlorhexidine's use by general practitioners. The side effects of long-term use, such as staining, and the availability of chlorhexidine also are discussed.

IgE antibody-mediated shock reaction caused by topical application of chlorhexidine

A case of an anaphylactic shock following topical application of chlorhexidine preparation is reported. Specific skin-sensitizing antibodies against chlorhexidine were demonstrated in the serum from the patient by a passive transfer test. IgE antibodies against chlorhexidine were also detected by radioallergosorbent technique (RAST). Paper discs conjugated with chlorhexidine-HSA (human serum albumin) significantly bound the IgE antibodies. Furthermore, all of the sera from seven other patients with shock reactions following the topical application of chlorhexidine preparation also showed high RAST counts. Both chlorhexidine gluconate and chlorguanide which represents approximately half a molecule of chlorhexidine inhibited the reaction in a dose-dependent fashion. It is suggested that the shock reactions following topical application of chlorhexidine are mediated by IgE antibodies against chlorhexidine and that chlorhexidine and chlorguanide share the same antigenic determinant.

The effect of mouthrinses on parameters characterizing human periodontal disease

The objective of the present clinical trial was to assess the efficacy of mouthwashes containing antiseptic agents on established and developing plaque and periodontal disease in adult subjects using a newly described clinical research model. The study was carried out in 21 patients with periodontal disease. At the baseline examination, all tooth surfaces-sites were studied with regard to dental plaque, gingivitis, bleeding on probing to the base of the pocket and probing pocket depths. The patients were subsequently randomly assigned to 1 of 3 groups, each consisting of 7 individuals. Group A rinsed with a 0.01% solution of Sanguinarine, group B rinsed with a 0.2% solution of chlorhexidine and group C rinsed with a placebo solution. No instructions regarding mechanical plaque control measures or information regarding the etiology and pathogenesis of periodontal disease were given to any of the patients during the course of the 6-weeks of trial. The clinical examination was repeated after 2 weeks use of the mouthwash preparations. Following the re-examination, all patients were subjected to scaling and root planing in 2 jaw quadrants chosen at random. After another 2 weeks, the 2nd re-examination was performed and the teeth in the 2 remaining jaw quadrants were thoroughly scaled. The final examination was performed 2 weeks later. During the 4 weeks of rinsing, without adjunctive professional mechanical debridement, the frequency distribution of plaque Index scores 2 + 3 did not change in the group of patients using the placebo solution, but was significantly reduced in both the chlorhexidine and the Sanguinarine groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Salivary Streptococcus mutans count and gingivitis in children after rinsing with a chlorhexidine-fluoride solution with and without strontium

Thirty schoolchildren, 9-12 yr old with high DMF score, rinsed their mouths twice a day for 3 days with a chlorhexidine-fluoride (CXF) solution or a chlorhexidine-fluoride-strontium (CXFSr) solution. Streptococcus mutans counts (CFU) were made from saliva incubated on MSB agar and the gingival bleeding was recorded both before and after the rinsing period. S. mutans count decreased significantly immediately after the rinsing with each of the solutions (from 650 X 10(3) to 170 X 10(3) CFU/ml by CXF and from 500 to 170 X 10(3) CFU/ml by CXFSr). Within about 18 days after the rinsing with each solution the salivary S. mutans counts returned to the original level. Gingival Bleeding Index (GBI) was significantly reduced by half through the CXF rinsing while the slight reduction by CXFSr was nonsignificant. Both of these changes were temporary. The results suggest that short rinsing periods with the CXF solution may be more advisable than daily rinses as a contribution to the maintenance of oral health in subjects or groups in need of such a prophylaxis. The weaker effect found with the CXFSr solution suggests that the cariostatic effect recently found in rats with the same solution may be due to other mechanisms than reduction of the oral S. mutans count.

Gingival bleeding after chlorhexidine rinses with or without mechanical oral hygiene

In a previous paper a slight increase in gingival bleeding tendency was reported after the use of chlorhexidine rinses in dental students with clinically healthy gingivae. For further clarification of this finding the study was repeated using a split mouth approach. 30 dental students brushed the teeth in either the left or the right side of their mouth twice daily during a 7-day period. After each brushing, they rinsed for 1 min with 10 ml of a 0.2% chlorhexidine digluconate solution. Both the Plaque Index (P1I) scores and the bleeding tendency after massage of the gingival margin were low at the initial examination. The low P1I scores at baseline were further reduced on both sides of the jaws. On the side which was only rinsed the P1I scores were higher than on the side of combined mechanical and chemical cleaning. The gingival bleeding tendency was found to decrease on the brushed side and to increase on the side which was only rinsed. An increased bleeding tendency was most often observed in those individuals whose gingivae were the healthiest at baseline. A SEM analysis of the 2 sides of the dentition indicated that bleeding after chlorhexidine rinses may be associated with irritation from debris which, after the 7-day period of no mechanical oral hygiene measures, seemed to obliterate the gingival sulcus.