Array analysis for T-cell associated cytokines in gingival crevicular fluid: Identifying altered profiles associated with periodontal disease status.

OBJECTIVE: Cytokine networks regulate innate and adaptive immune responses, which in turn are recognised to direct the progression or arrest of periodontal disease. This study aimed to compare the profile of seven cytokines, implicated in regulating T-cell networks, in gingival crevicular fluid (GCF) samples with differing classification of periodontal status. METHODS: GCF samples were collected from patients with strong clinical evidence for chronic periodontitis, aggressive periodontitis, gingivitis or no gingival inflammation. Cytokines IL-6, IFN-É£, IL-4, IL-2, IL-17 A, IL10 and TNFα were measured in each sample using a commercial cytometric bead array assay. Descriptive statistics were used to indicate central tendency, data scatter and analysis of variance for each cytokine concentrations between respective patient groups. Heat maps with dendrograms were produced to visualise hierarchical clustering and trends within the data. RESULTS: Median concentrations for all cytokines analysed were highest for gingivitis samples and lowest for aggressive periodontitis samples. The median concentration of IL-6 in gingivitis samples was observed to be 10.5 fold higher (˜17,300 pg/µl) than IL-6 in aggressive periodontitis samples (˜1600 pg/µl). Median concentrations of IL-10, IL-17 A and TNFα were also 2-2.2 fold higher in gingivitis samples compared to aggressive periodontitis. CONCLUSIONS: Descriptive statistical analysis noted raised concentrations of IL-6, IL-17 A and TNFα associated with gingivitis; pro-inflammatory cytokines usually associated with periodontal tissue destruction, including bone. Our results would suggest that these cytokines can additionally provide protective roles in preventing progression to advanced forms of periodontal disease. Potential for how these cytokines contribute to providing this role is discussed. CLINICAL SIGNIFICANCE: Defining the roles for the many cytokines involved in the pathogenesis of periodontal disease is far from complete. Consequently the results of this study serve to evidence proposals that cytokines can exhibit both pro- and anti-inflammatory effects, which is dependent on the signalling environment within which they exist and the antagonizing or modifying actions of other cytokines. Whilst future research is necessary to explore mechanistic action, our study contributes new knowledge suggesting that IL-6 and IL-17 A can provide roles in stabilising the lesion to limit disease progression, which does not preclude alternative roles in promoting periodontal bone loss in advanced forms of disease progression, which is also documented in the literature.

Real-time binding kinetic analyses of the interaction of the dietary stain orange II with dentin matrix.

OBJECTIVES: Dietary stains can be adsorbed into the dentin of teeth. Using Orange II as a model dietary stain, this study investigated the strength of its interaction with the mineral and protein components of dentin matrix and how hydrogen peroxide (H2O2) treatment influences this interaction. METHODS: Dentin slices were prepared from human teeth and were either deproteinized (5.6% sodium hypochlorite, 12 days), demineralised (0.5 M EDTA, 3 days) or left as intact control samples. Samples were stained with Orange II for 1-168 h, during which staining intensity was quantified by image analysis. Similarly, uptake of stain by deproteinized / demineralized samples treated with 10 or 30% H2O2 was investigated. Using surface plasmon resonance technology, real-time binding kinetics were determined assessing the interaction of Orange II with the dentin matrix protein constituents, collagen type I, biglycan, decorin, dentin sialoprotein and osteopontin. RESULTS: Deproteinization of dentin matrix reduced the uptake of the Orange II compared to the intact control. Conversely, demineralization of dentin samples increased the uptake of the dye. Treatment of samples for 48 h with H2O2 reduced subsequent uptake of the Orange II. Real-time kinetic analysis indicated moderate strength of binding for Orange II with collagen type I, weak binding with decorin and biglycan and negligible binding with dentine sialoprotein and osteopontin. CONCLUSION: These results indicate a predominant role for collagen type I, which accounts for 90% of the organic protein matrix of teeth, for attracting dietary stains. Binding analyses indicate that the interaction is highly dissociable, and further binding is reduced following H2O2 treatment. CLINICAL SIGNIFICANCE: This study provides new information regarding adsorption of dietary stains into tooth dentin, suggesting that they are attracted and moderately bound to the collagen type I matrix. This study also contributes valuable information for discussion for considering the effect of H2O2 on bleaching teeth and its influence on subsequent uptake of dietary stains following whitening treatments.

A prospective study of the prevalence of periapical pathology in severely worn teeth.

UNLABELLED: The aim of this article was to carry out a prospective audit on a convenience sample of all new patients referred to the toothwear clinic at Cardiff University Dental Hospital to establish the prevalence of undiagnosed periapical pathology. CLINICAL RELEVANCE: The low prevalence value for undiagnosed periapical pathology in patients with advanced toothwear suggests that, for many patients, toothwear is a slow process which allows the defence mechanisms of the pulp to counteract the effects of wear. It also questions the necessity of taking routine radiographs of teeth with wear into dentine, in the absence of clinical symptoms. This would reduce the total radiation dose delivered to the patient and preserve valuable healthcare resources.

A study in vitro to compare home and surgery vital bleaching techniques.

The aim of this study was to compare the effectiveness of three different types of commonly used bleaching techniques using an in-vitro model. Five groups of 10 tooth specimens were prepared and allocated randomly to treatment groups. The four treatment groups tested were a home tray bleaching product, an 'in surgery' tray bleaching product and an 'in surgery power bleaching' product for use with an activating light. The bleaching agent in the latter group was also tested without light activation to assess the additional benefit of the bleaching lamp. A placebo group treated with water was also included. Colour change was assessed using a Vita shade guide and an electronic chromometer. The mean change in shade guide units ranged from 10.9 to 13.2 units, with the 'in surgery' tray bleaching system producing the largest change. For the chromometer readings the mean change in tooth colour ranged from 3.6 to 25.6 units, with the night guard vital bleaching product producing the largest change. This study has demonstrated in vitro that all the different bleaching systems tested produced comparable changes in tooth colour.

Alcopop induced erosion: management in general denta practice.

UNLABELLED: Alcopops, which are fruit flavoured alcoholic drinks, have been implicated as an aetiological factor in dental erosion. They are commonly drunk by 18-25 year-olds owing to their fruity flavours, but increasingly in the UK they are consumed by underage teenagers. A popular lemon-based vodka alcopop is presented as a possible causative factor of dental erosion in a 19-year-old female, who started drinking it regularly at the age of 15 for four years. She was subsequently treated preventively and conservatively in a National Health Service (NHS) dental practice, in North Wales, using freehand compomer and minimally prepared porcelain veneers. CLINICAL RELEVANCE: Frequent consumption of excessive amounts of extrinsic acids causes significant dental erosion. Alcopops, owing to their high citrus fruit contents and acidic pH, are known to cause erosion. They are commonly drunk by adults up to their mid twenties, but increasingly so by underage teenagers, especially females.

The effect of dilution on the in vitro erosive potential of a range of dilutable fruit drinks.

BACKGROUND: Only one previous study has investigated the effect which dilution has on the erosive potential of dilutable fruit drinks. Based solely on measurement of neutralizable acidity, the authors concluded that the erosive potential of diluting juices may be reduced substantially by the addition of water. This has not been verified in an in vitro enamel erosion model. OBJECTIVE: The aim of this study was to examine the effect of dilution on the erosive potential of five dilutable fruit drinks. METHODS: For each product, the erosive potential of three dilutions (1 : 3, 1 : 6 and 1 : 15) was assessed by measuring the initial pH and neutralizable acidity; in vitro enamel erosion was measured by profilometry following immersion for 1 h. RESULTS: For the majority of products, increasing dilution from 1 : 3 to 1 : 15 produced a statistically significant rise in initial pH, though they remained markedly acidic. Increasing the dilution factor consistently produced a statistically significant decrease in neutralizable acidity. Increasing the dilution factor from 1 : 3 to 1 : 15 produced a statistically significant reduction in in vitro enamel erosion in only three of the five products tested. CONCLUSIONS: Increasing the dilution factor of dilutable fruit drinks within a range likely to be acceptable to the consumer may not effectively reduce their erosive potential.

Tooth bleaching by different concentrations of carbamide peroxide and hydrogen peroxide whitening strips: an in vitro study.

OBJECTIVE: To investigate the tooth whitening effects of various concentrations of carbamide peroxide (CP) gels and 6% hydrogen peroxide (HP) whitening strips used on an intrinsic, in vitro stain model in a simulated home-applied bleaching protocol. METHOD: Extracted third molars were sectioned and stained to Vita shade C4 using a standardized tea solution. Stained specimens were then bleached with 10, 15, 20, 22, and 30% CP gels applied in custom-made trays for 8-hour sessions for 14 days. A 6% HP whitening strip product was also tested in a regimen of twice-daily 30-minute treatments for 14 days. Shades were assessed at baseline and at 2, 5, 7, 10, and 14 days of treatment using a shade guide (SG) and a shade vision system (SVS), recorded as shade guide unit (SGU) changes from baseline, and CIE L*a*b* recordings using a chromometer. RESULTS: By day 14, all CP treatments resulted in at least 12 SGU improvements by SG and SVS methods: the HP treatment mean was just less than 12 SGU. With the chromometer, the CP improvements ranged from approximately 19 to 28 units and 16 units for the HP whitening strips. Observationally, by SG and SVS, CP treatments achieved the maximum improvement (12-13 SGU) at different time points: day 5 for 30% CP, day 10 for 22% CP, and day 14 for the other three treatments. SG and SVS data were virtually binary, switching from 0 to scores of 9 or above as bleaching progressed. The differences between the six treatments in the mean day to achieve a positive SG or SVS score (9 or more units) approached significance. For each of the SG, SVS, and L*a*b* scores, the dose-response correlation with CP concentration was significant at one or more assessment times. SG and SVS showed extremely strong agreement in detecting change and substantial agreement with L*a*b*. CONCLUSION: This in vitro study supports the limited data available from the very few available randomized controlled clinical trials indicating that CP and HP home-use bleaching systems can achieve considerable tooth whitening outcomes, albeit at different rates, which appear to be concentration dependent. CLINICAL SIGNIFICANCE: There is a clear significant relationship for both concentration and duration of exposure for CP bleaching agents. The final shade change is independent of the concentration of bleaching agent, with time as the dominant variable. Higher concentrations of CP that have not been investigated previously may be a treatment option for esthetic improvement of shade where time is at a premium, but caution must be exercised in view of the possible increased incidence of sensitivity.

The ability of fruit teas to remove the smear layer: an in vitro study of tubule patency.

OBJECTIVES: Fruit teas are know to have an erosive effect on enamel, but the effects on dentine are unknown. Lesions of dentine hypersensitivity have numerous patent dentinal tubules and the aim of this paper was to examine the ability of various fruit teas to remove the smear layer. METHODS: The erosive potential of a variety of fruit teas was assessed in the laboratory by measuring their pH and neutralisable acidity. Smeared dentine specimens were prepared from extracted teeth and the ability of each tea to remove the smear layer was assessed by measuring the diameter and area of the opened tubules and counting the number of patent tubules seen in a unit area using scanning electron microscopy. A 0.2% citric acid solution was used as a positive control. RESULTS: The pH of the fruit teas ranged from 2.98 to 3.95 and the neutralisable acidity ranged from 10.63 to 33.0 ml of 0.1 M NaOH. All the fruit teas tested were able to remove the smear layer. The mean diameter of the tubules ranged from 0.61 to 1.14 microm and the mean area ranged from 0.31 to 1.03 microm2. The number of patent tubules per specimen ranged from 13 to 121. CONCLUSION: All the fruit teas tested were found to be highly acidic and able to remove the smear layer.

The dental treatment needs and oral side effects of patients undergoing outpatient cancer chemotherapy.

An increasing number of patients receive cancer chemotherapy on an out-patient basis. Dentists therefore need to be aware of the consequences of cancer chemotherapy. Two hundred and eighteen patients attending a specialist oncology centre were examined and the oral side effects recorded. The patients also completed a structured interview to examine the advice they had been given by health care professionals prior to starting chemotherapy. Clinical examination revealed a significant dental treatment need with 16% of patients requiring restorations and 66% requiring professional periodontal care. The commonest oral side effects were altered taste sensation (52%), xerostomia (35%) and mucositis (22%). All these side effects are unpleasant and may have a significant effect on a patient's quality of life.

Comparison of three in-office bleaching systems based on 35% hydrogen peroxide with different light activators.

PURPOSE: To compare in vitro the bleaching effects obtained with and without the use of the various lights on power bleaching systems. METHODS: 19 groups of five tooth specimens were prepared and allocated randomly to treatments. Only specimens with shade C4 were accepted for the study. Three commercial bleaching products all based on 35% hydrogen peroxide were used with and without four different light sources. Shade assessments were made using a Shade Guide (SG), Shade Vision System (SVS) and chromometer. RESULTS: For SG, all but the light only treatment resulted in measurable improvement in shade ranging from 4.6 to 14.6 shade guide units. Similar findings were apparent with SVS and chromometer. No change was seen in the light only treatments by SVS or SG with very small changes by chromometer. In mean terms with all three gels, least change was noted when there was no light used. For SG, SVS and chromometer data analysis over all treatment groups, excluding light only treatments, revealed highly significant differences. Within bleach product treatment differences were only significant with one gel both with and without light activation. Differences between gels with the same light and no light revealed some significant differences in SG and chromometer data but not SVS. In mean terms the order of efficacy of gels with each light and no light was the same for the majority of data sets.

The effectiveness of seven denture cleansers on tea stain removal from PMMA acrylic resin.

PURPOSE: In this study, seven denture cleansers were evaluated for their mode of action of tea stain removal from Perspex acrylic resin material. MATERIALS AND METHODS: Perspex acrylic resin specimens were stained using a combination of chlorhexidine and tea solution. The specimens were also treated with saliva to form an initial pellicle layer and facilitate the uptake of the stain. The capacity for stain removal was determined by measuring the optical density of the treated specimens by using a spectrophotometer. These were then exposed, for 5 minutes, to seven denture cleansers to demonstrate the percentage stain-removal ability of each cleanser. The same procedure was applied for roughened Perspex acrylic resin specimens. Water was used as a control in the two parts of the experiment. RESULTS: The products containing alkaline hypochlorite had the highest ability for removing stain from the acrylic resin material together with a bleaching effect. The results varied when the same denture cleansers were used on the roughened Perspex surface, and this was attributed to the presence of irregularities and porosities on the blocks. CONCLUSION: Denture cleansing agents containing hypochlorite and Boots Denture Cleaning Powder (constituents not stated by the manufacturer) exhibited the ability to remove stain from the denture base materials most effectively. Irregularities and porosities present on the denture surface played a major role in reducing the activity of denture cleaning agents and hence increased stain and plaque retention.

An in vitro assessment of the erosive potential of conventional and white ciders.

The aim of this in vitro study was to investigate the erosive potential of a range of traditional and white ciders using standard laboratory tests. It measured the pH, 'neutralisable acidity' and the amount of surface enamel lost following immersion over a period of 4 hours. The pH was measured with a digital pH meter and the 'neutralisable acidity' was measured as the volume of 0.1 M sodium hydroxide required to increase the pH to neutrality. Surface enamel loss was measured at 1, 2, 3 and 4 hours using profilometry. The pH on opening ranged from 2.96 to 4.04 and the 'neutralisable acidity' ranged from 14.54 to 21.47 mls. The amount of surface enamel lost following four hours immersion ranged from 8.60-23.95 microns, compared to 12.85 microns for an orange juice control. All the ciders tested were acidic and had considerable erosive potential in vitro which was broadly similar to that of orange juice. A wide variation was found between different commercial brands and this information should be useful when counselling patients with tooth surface loss.