Soft drink, software and softening of teeth - a case report of tooth wear in the mixed dentition due to a combination of dental erosion and attrition.

This case report describes a 9-year-old boy with severe tooth wear as a result of drinking a single glass of soft drink per day. This soft drink was consumed over a period of one to two hours, while he was gaming intensively on his computer. As a result, a deep bite, enamel cupping, sensitivity of primary teeth and loss of fillings occurred. Therefore, dentists should be aware that in patients who are gaming intensively, the erosive potential of soft drinks can be potentiated by mechanical forces leading to excessive tooth wear.

The erosive potential of candy sprays.

OBJECTIVE: To determine the erosive potential of seven different commercially available candy sprays in vitro and in vivo. MATERIAL AND METHODS: The erosive potential was determined in vitro by measuring the pH and neutralisable acidity. The salivary pH and flow rate were measured in healthy volunteers after administration of a single dose of candy spray. RESULTS: Candy sprays have an extremely low pH (1.9-2.3) and a neutralisable acidity varying between 0.8-1.6 ml of 0.25M NaOH. In vivo, candy sprays induced a short-term 3.0 to 5.8-fold increase in salivary flow rate with a concomitant drop in salivary pH to values between 4.4 and 5.8. CONCLUSION: All candy sprays tested have an erosive potential. This information is of use for clinicians counselling juvenile patients with dental erosion.

The erosive potential of lollipops.

AIM: To determine the erosive potential of several commercially available lollipops and the protective effect of saliva. METHODS: The erosive potential of lollipops was determined in vitro by measuring the pH and neutralisable acidity. Subsequently, 10 healthy volunteers tested different types of lollipops. Whole saliva was collected 5 minutes before, 15 minutes during and 10 minutes after consumption. Salivary flow rate and pH were determined. RESULTS: Fruit flavoured and cola flavoured lollipops have a very low pH (2.3 - 2.4). Yogurt-containing and salmiak (salty liquorice) flavoured lollipops have much higher pH values (3.8-4.7). The neutralisable acidity of 1g of lollipop showed a large variation from < 200 microl to > 1700 microl 0.1 M NaOH. In vivo, lollipops induced 2.5 to 4.7-fold increase in salivary flow rate with a concomitant drop in salivary pH. For fruit flavoured and cola flavoured lollipops the salivary pH dropped below pH 5.5. For strawberry yogurt and salmiak lollipops, the salivary pH remained above this critical value. The volunteers did not report significant differences in preferences for the lollipops. CONCLUSIONS: Lollipops differ considerable in erosive potential, with fruit flavoured and cola flavoured lollipops having the highest risk for inducing dental erosion. This information is of use for clinicians counselling juvenile patients with dental erosion.

Ecstasy (MDMA) and oral health.

3,4-methylenedioxymethamphetamine (MDMA), more commonly known as 'ecstasy' or XTC, is frequently used by young adults in the major cities. Therefore, it is likely that dentists might be confronted with individuals who use ecstasy. This review describes systemic and oral effects of ecstasy. Life-threatening complications include hyperthermia, hyponatraemia and liver failure. In addition, psychotic episodes, depression, panic disorders and impulsive behaviour have been reported. Oral effects include xerostomia, bruxism, and an increased risk of developing dental erosion. Mucosal changes have also been reported. Recent use of ecstasy may interfere with dental treatment. Finally, the potential use of saliva for non-invasive detection of ecstasy is discussed.

Interference of electrical dental equipment with implantable cardioverter-defibrillators.

OBJECTIVE: To determine whether electromagnetic interference with implantable cardioverter-defibrilllators (ICDs) occurs during the use of electrical dental equipment. MATERIAL AND METHODS: Ten different electrical dental devices were tested for their ability to interfere with the function of three types of ICDs at different intervals for 90 seconds, during which the ICD activity was monitored by telemetry. RESULTS: Only one ultrasonic bath cleaner interfered with two of the ICDs tested up to a distance of 12.5 cm, both during continuous use and intermittent operation. In contrast, the dental chair, electrosurgical unit, both handpieces, ultrasonic tooth scaler, both amalgamators and two other types of ultrasonic bath cleaners failed to produce interference at the minimum distance of 2.5 cm. CONCLUSION: Our results suggest that normal clinical use of dental electrical equipment does not have significant effects on the ICDs tested.

Acute effects of hemodialysis on salivary flow rate and composition.

AIMS: To evaluate acute effects of hemodialysis (HD) on the salivary flow rate, pH and biochemical composition before, during and after completion of a dialysis session. MATERIAL AND METHODS: Unstimulated whole saliva (UWS) and chewing-stimulated whole saliva (CH-SWS) were collected in 94 HD patients. Salivary flow rate, pH, concentrations of total protein, albumin, cystatin C, secretory immunoglobulin A (S-IgA) and of sodium, potassium and urea were measured. RESULTS: HD had an acute stimulating effect on the salivary flow rate (UWSbefore = 0.30+/-0.22 ml/min, UWSduring = 0.39+/-0.25 ml/min, p < 0.005). The mean pH of UWS showed a small but significant increase during HD mainly due to an increased watery secretion from the salivary glands. The salivary biochemical constituents changed markedly, but no significant difference in output was found. The electrolyte concentration did not change significantly during dialysis. The level of urea in CH-SWS declined to 40% (Ureabefore = 25.+/-6.4 mmol/l, Ureaduring = 15.3+/-4.5 mmol/1). CONCLUSIONS: This study shows that HD has significant acute effects on both salivary secretion rate and protein concentrations in saliva. We conclude that the observed changes in salivary concentrations and proteins are mainly due to an increased watery secretion from the salivary glands.

Oral and salivary changes in patients with end stage renal disease (ESRD): a two year follow-up study.

OBJECTIVES: To compare oral health, salivary flow rate, xerostomia and thirst in end stage renal disease (ESRD) patients remaining on dialysis treatment and after renal transplantation. DESIGN: Longitudinal observation. SETTING: ESRD patients recruited from dialysis centres in Amsterdam, The Hague and Utrecht, The Netherlands. METHOD: At baseline and after two years, salivary flow rates, xerostomia and thirst were determined in 43 ESRD patients. The number of decayed missing filled teeth/surfaces (DMFT/DMFS) was recorded, and periodontal status assessed. RESULTS: After renal transplantation (n = 20), the salivary flow rate increased significantly from UWS = 0.30 +/- 0.21 ml/min to 0.44 +/- 0.29 ml/min (p <0.001) and the level of xerostomia and thirst decreased. After two years, the percentage of bleeding on probing in dialysis patients (n = 23) decreased from 29.5 +/- 25.4% to 10.3 +/- 12.3%, (p <0.05). No differences in DMFT and DMFS were observed between dialysis and renal transplant patients. CONCLUSIONS: DMFT, dental plaque, gingival bleeding and periodontal indices did not change remarkably after two years, comparing dialysis and renal transplant patients. Renal transplantation enhances salivary flow and decreases symptoms of xerostomia and thirst, and hence enhances the potential to improve the quality of life of affected individuals.

Design of a peptibody consisting of the antimicrobial peptide dhvar5 and a llama variable heavy-chain antibody fragment.

Immunoconjugates have been widely studied as potential therapeutics for infectious diseases to direct unspecific antimicrobials to pathogens. In this study, the recombinant approach was used for expression of the immunoconjugate composed of the variable domain of a llama heavy-chain antibody (VHH) against Streptococcus mutans and dhvar5, a synthetic antimicrobial peptide. Before cloning, the impact of the elongation of the peptide termini on its biological activity was evaluated by chemical synthesis of the N- or C-termini extended dhvar5 peptides. As the elongation of the C-terminus had a greater influence on decline of the antimicrobial activity, the N-terminal fusion was designed. To promote in vivo release of the active peptide, a factor Xa cleavage site was inserted between VHH and dhvar5. Propagation of transformed Escherichia coli with the constructed plasmid was only possible in the absence of isopropyl beta-D-thiogalactoside (IPTG). Although these data demonstrate that the diminished antimicrobial activity of dhvar5 by the N-terminal fusion to VHH was not sufficient for the protection of the bacterial host cells against the peptide lethal effect, an insight into propeptides biological activities may be beneficial not only for new and more successful rearrangement of the VHH-dhvar5 immunoconjugate construct, but also design of the other recombinant molecules composed of peptides toxic to host cells.

The oral health status of dentate patients with chronic renal failure undergoing dialysis therapy.

OBJECTIVE: The aim of this study was to compare the oral health status of chronic renal failure (CRF) patients on renal replacement therapy with a matched reference population. DESIGN: Cross-sectional study. SUBJECTS: Forty-two dentate CRF patients--aged 25-52 years old--were matched with a reference group of 808 dentate subjects. METHODS: The oral health was assessed using decayed missing filled (DMF) indices, simplified oral hygiene index and periodontal status. An oral health questionnaire was used to assess self-reported dental problems. Student t-tests and chi-square tests were performed to compare the CRF patients with the controls. RESULTS: All index-scores in the CRF patients were comparable with the controls except for number of teeth covered with calculus that was significantly higher (P < 0.05) in CRF patients (4.1 +/- 2.6) than in controls (3.0 +/- 2.9). The self-reported oral health questionnaire revealed a trend for increased temporomandibular complaints in CRF patients (16.7%vs 5.7% in controls; P = 0.06) as well as bad taste (31.0%vs 6.8% in controls, P = 0.08). CONCLUSIONS: For most dental aspects, the oral health of CRF patients is comparable with controls.

Family 2 cystatins inhibit osteoclast-mediated bone resorption in calvarial bone explants.

Osteoclastic bone resorption depends on the activity of various proteolytic enzymes, in particular those belonging to the group of cysteine proteinases. Biochemical studies have shown that cystatins, naturally occurring inhibitors of these enzymes, inhibit bone matrix degradation. Since the mechanism by which cystatins exert this inhibitory effect is not completely resolved yet, we studied the effect of cystatins on bone resorption microscopically and by Ca-release measurements. Calvarial bone explants were cultured in the presence or absence of family 2 cystatins and processed for light and electron microscopic analysis, and the culture media were analyzed for calcium release. Both egg white cystatin and human cystatin C decreased calcium release into the medium significantly. Microscopic analyses of the bone explants demonstrated that in the presence of either inhibitor, a high percentage of osteoclasts was associated with demineralized non-degraded bone matrix. Following a 24-h incubation in the presence of cystatin C, 41% of the cells were adjacent to areas of demineralized non-degraded bone matrix, whereas in controls, this was only 6%. If bone explants were cultured with both PTH and cystatin C, 60% of the osteoclasts were associated with demineralized non-degraded bone matrix, compared to 27% for bones treated with PTH only (P < 0.01). Our study provides evidence that cystatins, the naturally occurring inhibitors of cysteine proteinases, reversibly inhibit bone matrix degradation in the resorption lacunae adjacent to osteoclasts. These findings suggest the involvement of cystatins in the modulation of osteoclastic bone degradation.

Salivary agglutinin/DMBT1SAG expression is up-regulated in the presence of salivary gland tumors.

Salivary agglutinin (SAG) is encoded by the gene Deleted in Malignant Brain Tumors 1 (DMBT1) and represents the salivary variant of DMBT1 (DMBT1(SAG)). While SAG is a bona fide anti-caries factor, DMBT1 was proposed as a candidate tumor-suppressor for brain, digestive tract, and lung cancer. Though DMBT1(SAG) is expressed in the salivary glands, its expression in salivary gland tumors is unknown. Here we analyzed DMBT1(SAG) expression in 20 salivary gland tumors and 14 tumor-flanking tissues by immunohistochemistry. DMBT1(SAG) in salivary gland tumors resembles the changes of expression levels known from DMBT1 in tumors in other cancer types. Particularly, DMBT1(SAG) was up-regulated in 10/14 tumor-flanking tissues, and a strong staining of the luminal content in the tumor and/or the tumor-flanking tissue was observed in 14/20 cases. This suggests that, in addition to its role in caries defense, SAG may serve as a potential tumor indicator and/or tumor suppressor in salivary gland tissue.

Preferences and saliva stimulation of eight different chewing gums.

OBJECTIVES: Chewing gums have been studied for clinical use to stimulate the salivary flow rate in healthy and diseased individuals. However, differences in preferences of chewing gums may influence patient compliance during long-term use. Therefore, we compared the effect of several chewing gums on the flow rate of whole saliva and pH, and investigated the preferences of these gums. METHODS: 83 healthy subjects participated in the first part of the study. Both parafilm-stimulated and chewing gum-stimulated whole saliva from 8 different chewing gums was collected and salivary flow rate and pH were determined. In another group of 112 healthy subjects, we investigated the preferences for the chewing gums with a 10-item questionnaire. RESULTS: All gums had comparable effects on salivary flow rate and pH. The average increase in flow rate was 187% during the first minute of chewing compared with parafilm stimulation. After 10 minutes of gum chewing, the amount of saliva was equal to parafilm stimulation. The questionnaire showed differences in preferences for the chewing gums, which were related to taste and gum shape. Gender interactions were observed for sparkling taste (p = 0.019), total judgement (p = 0.047) and the willingness to use the gum for several weeks (p = 0.037). CONCLUSIONS: Although all chewing gums stimulated the salivary flow rate equally, the observed differences in preferences may influence long-term compliance. Therefore, we recommend that chewing gums are tested before the start of clinical studies, to identify the most accepted chewing gum for specific groups of patients.

Degradation of antimicrobial histatin-variant peptides in Staphylococcus aureus and Streptococcus mutans.

Histidine-free variants of salivary histatin 5 have a broad antimicrobial activity against various bacteria. In relation to a possible therapeutic application, we were interested in the susceptibility of these small peptides (14 amino acids long) to microbial proteinases and whether this affects their antimicrobial activity. Analyses by SDS-PAGE of supernatants of peptide-bacteria incubation showed a reduction in protein bands within 15 minutes' incubation, as a result of cellular internalization. Degradation products of dhvar1 and dhvar2 appeared within one hour in the supernatants of Streptococcus mutans and Staphylococcus aureus. In contrast, the variants dhvar3 and dhvar4 were more resistant to degradation under the same conditions. MALDI-TOF analyses identified cleavage of dhvar1 and dhvar2 at Glu(6). The N-terminal peptide part (1-6) of dhvar1 and 2 showed no bactericidal activity, while peptide fragment (7-14) showed a highly reduced bactericidal activity.

Current therapies for xerostomia and salivary gland hypofunction associated with cancer therapies.

In cancer patients, as in the general population, medication is the most common cause of xerostomia. In general, saliva flow in these patients can be stimulated by mechanical or pharmacological stimulation of the salivary glands. Painful damaged oral mucosa can be treated by softening, lubricating mouthwashes or gels. A specific group of patients are those receiving radiotherapy for malignant tumours in the head and neck region. This treatment is inevitably associated with damages to the oral tissues, including the salivary glands, resulting in salivary gland hypofunction. When residual secretory capacity is present, it is advisable to stimulate the salivary glands by mechanical or gustatory stimuli regularly in these patients as supportive oral care. Alternatively, salivary flow can be stimulated by the use of cholinergic pharmaceutical preparations, such as pilocarpine or cevimeline. After the radiation therapy is ended, a dental check-up should be done every 3 months to allow control of any incipient oral inflammation and dental decay. For daily use, a special dentifrice (e.g. children's toothpaste) is recommended, since the taste of a regular dentifrice may be too strong for these patients. Nocturnal oral dryness can be alleviated by spraying the oral surfaces with water, or by applying a small amount of dentifrice on the dental smooth surfaces. When stimulation of salivary secretion fails, patients can be given palliative oral care in the form of application of mouthwashes and saliva substitutes. The daily use of a mouthwash, e.g. Biotène, Oral Balance or Zendium, or one of the saliva substitutes is indicated. Different types of saliva substitutes are now commercially available, containing different polymers as thickening agents, e.g. carboxymethylcellulose (Oralube and Glandosane), polyacrylic acid, and xanthan gum (Xialine). Recent developments, which are, however, still in the experimental stage, are bio-active saliva substitutes and mouthwashes containing antimicrobial peptides to protect the oral tissues against microbial colonization and to suppress and to cure mucosal and gingival inflammation.

Distinct localization of MUC5B glycoforms in the human salivary glands.

Salivary mucins, encoded by the MUC5B gene, make up a heterogeneous family of molecules, which are secreted by several glands, including the submandibular, sublingual, and palatine glands. Previous studies have shown that heterogeneity in the salivary mucin population is related to its multiglandular origin. In the present study we address the question to what extent the mucin (MUC5B) population from a single human salivary gland is made up of different glycoforms. Using monoclonal antibodies to defined protein and sulfated carbohydrate epitopes specific to MUC5B, we conduct an immunohistochemical study of different salivary gland types, including submandibular, sublingual, and labial glands. In all tissues studied we found a mosaic expression pattern of sulfo-Lewis a antigen, recognized by mAb F2, which in salivary glands is exclusively present on MUC5B. On the other hand, mucous acini were uniformly labeled by mAb EU-MUC5Bb, evoked against a peptide-stretch of the tandem repeat region of MUC5B. Double staining with both antibodies confirmed the presence of MUC5B-positive/sulfo-Lewis a-positive cells, as well as MUC5B-positive/sulfo-Lewis a-negative cells within one glandular unit. These results indicate that one and the same salivary gland synthesizes different MUC5B glycoforms.

A rapid solid-phase fluorimetric assay for measuring bacterial adherence, using DNA-binding stains.

In this report, we describe the validation of a rapid, single-step, microtiter plate method for quantifying bacterial adherence, based on fluorescent labeling of microorganisms with cell-permeable fluorescent DNA-binding probes. We have tested the binding to saliva-coated microtiter plates of bacteria, including Helicobacter pylori and viridans streptococci (S. mitis, S. gordonii, S. sanguis), known to interact with salivary components. Furthermore, we tested the short-term and longer-term temporal stability of a saliva-mediated adherence of these bacteria in a healthy population (N=30). The assay exhibited excellent reliability statistics, yielding within-assay variability coefficients ranging from 4.9% to 11%. A range of approximately 5 x 10(4)-1 x 10(7) cells could be detected. This method may be generally applicable to study surface binding of virtually any microbial species, while obviating the need of radioactive materials or specific antibodies for quantification, thus providing a procedure that is useful to both basic and clinical research.

Effect of periodontal treatment on the activity of chitinase in whole saliva of periodontitis patients.

Human salivary chitinase could play a role in the defence against chitin-containing oral pathogens. The activity levels of chitinase in the whole saliva of periodontitis patients were significantly higher than those in saliva from controls. Periodontal treatment for a period of 5-6 months resulted in a three- to fourfold decrease in this enzyme activity. The activity of beta-N-acetylhexosaminidase, which is another enzyme that hydrolyses glycosidic linkages, also decreased as a result of treatment, although to a lesser extent. The decrease in chitinase activity upon treatment of the disease did not correlate with the decrease that was seen in clinical attachment loss and bleeding on probing, and only a weak correlation was observed with the changes in probing pocket depth and plaque index. No correlations were found between the above clinical parameters and the decrease in beta-N-acetylhexosaminidase activity.