Unstimulated and stimulated salivary characteristics of 12–13-year-old schoolchildren with and without dental erosion

Review of paediatric gastrointestinal physiology relevant to the absorption of orally administered medicines

Despite much progress in regulations to improve paediatric drug development, there remains a significant need to develop better medications for children. For the design of oral dosage forms, a detailed understanding of the specific gastrointestinal (GI) conditions in children of different age categories and how they differ from GI conditions in adults is essential. Several review articles have been published addressing the ontogeny of GI characteristics, including luminal conditions in the GI tract of children. However, the data reported in most of these reviews are of limited quality because (1) information was cited from very old publications and sometimes low quality sources, (2) data gaps in the original data were filled with textbook knowledge, (3) data obtained on healthy and sick children were mixed, (4) average data obtained on groups of patients were mixed with data obtained on individual patients, and (5) results obtained using investigative techniques that may have altered the outcome of the respective studies were considered. Consequently, many of these reviews draw conclusions that may be incorrect. The aim of the present review was to provide a comprehensive and updated overview of the available original data on the ontogeny of GI luminal conditions relevant to oral drug absorption in the paediatric population. To this end, the PubMed and Web of Science metadatabases were searched for appropriate studies that examined age-related conditions in the oral cavity, esophagus, stomach, small intestine, and colon. Maturation was observed for several GI parameters, and corresponding data sets were identified for each paediatric age group. However, it also became clear that the ontogeny of several GI traits in the paediatric population is not yet known. The review article provides a robust and valuable data set for the development of paediatric in vitro and in silico biopharmaceutical tools to support the development of age-appropriate dosage forms. In addition, it provides important information on existing data gaps and should provide impetus for further systematic and well-designed in vivo studies on GI physiology in children of specific age groups in order to close existing knowledge gaps and to sustainably improve oral drug therapy in children.

The interrelationship between xerogenic medication use, subjective oral dryness and tooth wear

OBJECTIVE

To investigate the association between xerogenic medication use and tooth wear among American adults and whether this association can be explained by subjective oral dryness.

METHODS

We used data from 3578 adults who participated in the National Health and Nutritional Examination Survey (NHANES). Tooth wear was clinically determined using the modified Tooth Wear Index. Information on xerogenic medication use, subjective oral dryness (amount of saliva in mouth and feeling the mouth dry when eating) and potential confounders (sociodemographic factors, dental insurance coverage, gastroesophageal reflux disease medication use and soft drinks intake) were self-reported. The associations among xerogenic medication use, subjective oral dryness and tooth wear were assessed in regression models adjusting for confounders.

RESULTS

Adults taking xerogenic medication had greater odds of reporting too little amount of saliva and feeling the mouth dry when eating. In addition, participants taking one and multiple (two or more) xerogenic medications had, respectively, 1.53 (95 % CI: 1.01-2.32) and 1.44 (95 % CI: 0.62-3.33) greater odds of having tooth wear than those taking no xerogenic medications. In a regression model including all explanatory variables, the association of xerogenic medication use with tooth wear was fully attenuated whereas subjective oral dryness (amount of saliva in mouth but not feeling the mouth dry when eating) remained positively associated with prevalence of tooth wear. Similar findings were obtained with long-term use of xerogenic medication (in the past month and for three or more years).

CONCLUSION

Current (last month) use of xerogenic medication was associated with the presence of tooth wear. This association was accounted for by subjective indicators of oral dryness.

CLINICAL SIGNIFICANCE

Dentists should be familiar with the possible connection between patient's medical prescription and tooth wear. Changing prescriptions to non-xerogenic alternatives, whenever possible, could improve patients' oral condition. The findings also suggest that patients may recognise, through the perception of dry mouth, when medication is placing them at risk.

Salivary profile of children with erosive tooth wear: a transversal study

The aim of the present transversal study was to evaluate the clinical and biochemical salivary parameters of children with and without erosive tooth wear (ETW). The study population was children aged 4 to 9 years. A trained and calibrated examiner (kappa value for intraexaminer reliability = 0.89) classified the children into ETW (n = 24) and control groups (n = 24), and applied the O'Brien index. The salivary flow rate was initially evaluated by stimulated sialometry (paraffin chewing). Afterwards, the collected saliva was submitted to biochemical analyses of pH, uric acid, total buffering capacity, ferric-reducing antioxidant power, reduced glutathione, calcium, and phosphorus. Among the ETW children, 20 (83%) had dental lesions restricted to enamel, and 4 (17%) presented lesions affecting both enamel and dentin. A statistically significant difference between the groups was obtained only for the pH values (t-test; p = 0.004), with averages of 7.31 and 7.56 for the control and the ETW groups, respectively. Considering the parameters evaluated in general, it is suggested that the salivary profile of children with ETW does not differ considerably from that of children without ETW. However, the pH mean value seems to be slightly higher in ETW children, but is still within the normal physiological range.

Oral findings in children and adolescents with Prader-Willi syndrome

OBJECTIVE

To assess the significance of changes in the saliva in the etiology of gingivitis and tooth wear in children and adolescents with Prader-Willi syndrome (PWS).

MATERIALS AND METHODS

The study included 80 (2.8-18 years old; 39 girls and 41 boys): 40 in PWS group (mean age 8.0 ± 4.24 years) and 40 in control group (mean age 7.9 ± 4.12 years). General condition, oral para-functional habits, tooth wear (modified TWI), oral hygiene and gingival status (Plaque Index (PLI) and Gingival Index (GI)), localization of gingivitis, and salivary characteristics were assessed. The chi-square test, the Mann-Whitney U test, Spearman's rank correlation, and odds ratio based on logistic regression in a statistical analysis were applied.

RESULTS

Chances of gingivitis were increased by low PLI (odds ratio (OR) = 32.53), low resting salivary flow (OR = 3.96), increased viscosity of saliva (OR = 3.54), and mouth breathing (OR = 8.17). For gingivitis in anterior regions, low PLI (OR = 107.67), low resting (OR = 5.73) and stimulated (OR = 1.86) salivary flow, increased viscosity of saliva (OR = 5.87), mouth breathing (OR = 10.00), and low stimulated salivary flow (OR = 3.18) were observed. Tooth wear rates were increased by teeth grinding (OR = 16.20), mouth breathing (OR = 4.33), increased viscosity of saliva (OR = 11.67) and low resting (OR = 6.07), and stimulated (OR = 4.22) salivary flow.

CONCLUSIONS

In PWS, reduced salivary secretion, increased viscosity, of saliva and mouth breathing increase the risk of plaque-induced gingivitis and tooth wear.

CLINICAL RELEVANCE

The prevention and treatment of tooth wear and gingivitis in PWS patients is necessary not only to treat bruxism and mouth breathing but also to limit the influence of negative changes of saliva.

Epidemiological investigation of non-carious cervical lesions and possible etiological factors

Background

Epidemiological studies of non-carious cervical lesions (NCCLs) are being conducted in all geographical regions, which is completely justified, considering the high frequency of these lesions and possible consequences. Data obtained from such studies are of great importance because, beside describing the extent and degree of lesions, they can also point to specific etiological factors. The purpose of this study was to analyze the frequency and distribution of NCCLs among the patients of Faculty of Dentistry in Pancevo, Serbia, and to investigate the impact of certain etiological factors on the frequency of NCCLs.

Material and Methods

The study included 394 patients, who were clinically examined for the presence of NCCLs and interviewed about potential etiological factors using specially designed questionnaire. Saliva samples were analyzed for 30 patients with multiple NCCLs (≥3) and 30 patients without signs of cervical lesions and restorations. Subject – level logistic regression was used to analyze the association of potential etiological factors and presence of NCCLs and Wilcoxon test for the quantity and quality of saliva.

Results

NCCLs were diagnosed at 68.5% from total number of respondents, 15% from all present teeth were affected. The highest prevalence was recorded on premolars. Presence of lesions significantly increased with age. Frequent consumption of citrus fruit was associated with the presence of NCCLs. Significantly lower frequency of NCCLs was recorded among subjects who frequently chew gums. Significantly lower pH values of unstimulated and stimulated saliva were recorded in the group of patients with multiple NCCLs compared to control group.

Conclusions

This study showed high frequency of NCCLs among subjects of different age. Premolars were the most frequently affected. Age, frequent consumption of citrus fruit and lower salivary pH value were associated with an increased occurrence of NCCLs. Chewing gums habit was associated with an decreased occurrence of NCCLs.

Key words:NCCL, abrasion, erosion, abfraction, saliva.

Assessment of oxidative stress in saliva of children with dental erosion

Objective

To evaluate oxidative stress in saliva of children with dental erosion as compared to children with no erosion.

Methods

One single examiner, trained and prepared to make diagnosis of dental erosion according to the Basic Erosive Wear Examination index, selected 40 children aged 4 to 6 years, who attended a pediatric dentistry prevention clinic. Two groups were formed - one comprising children with dental erosion (n=22), and another with no dental erosion (n=18). The quantity of dental biofilm was verified using the Simplified Index of Oral Hygiene, and unstimulated saliva was collected for biochemical analyses. The following were assessed in saliva: flow rate, buffering capacity, pH, and total protein concentration. Malondialdehyde levels were also verified to determine oxidative stress and total antioxidant status.

Results

The quantity of biofilm was smaller in children with mean dental erosion±standard deviation (0.76±0.25), as compared to those with no dental erosion (1.18±0.28). There was no statistical difference in saliva parameters of oxidative stress in children with dental erosion.

Conclusion

The activity of oxidative stress in saliva did not influence dental erosion process when in its early stages.

Preliminary findings on the correlation of saliva pH, buffering capacity, flow rate and consistency in relation to waterpipe tobacco smoking

The aim of the present comparative study was to compare some salivary characteristics between exclusive waterpipe smokers (EWPS) and non-smokers. 72 males (36 EWPS) were recruited. The volume of stimulated saliva was determined and divided by the duration of saliva collection. The pH was measured directly using a pH meter. The buffering capacity was determined using a quantitative method which involved the addition of 10 µl HCl. Up to a total of 160 µL was titrated up to obtain a pH titration curve. At 50 µL of titrated HCl, buffering capacity was ranked into three categories: high, medium and low. EWPS and non-smoker groups had similar flow rates (1.81 ± 0.79 and 1.78 ± 1.14 mL min-1) and similar baseline pH (6.60 ± 0.37 and 6.76 ± 0.39). Statistically significant differences in the two groups' pH were observed from 30 to 160 µL of titrated up HCl. At 50 µL of titrated up HCl, the EWPS group compared to the non-smoker group had a significantly higher pH (4.79 ± 0.72 vs. 5.32 ± 0.79). To conclude, waterpipe tobacco smoking alters the buffering capacity but does not alter either salivary flow rates or the baseline pH and consistency.

Clinical enamel surface changes following an intra-oral acidic challenge

OBJECTIVES

Investigation of early enamel erosion using replica impressions to compare changes in enamel surface topography in vivo prior to and over a 24 h period following acid challenge.

METHOD

A single treatment, blinded, enamel replica clinical study was undertaken in 20 healthy subjects. Replica tooth impressions were taken at baseline, following acid challenge and 2, 4, 7 and 24 h post challenge. Subjects consumed 500 ml of acidic soft drink over 30 min. Scanning electron microscopy of surface tomography was characterised with a descriptive 5 point scale by four judges. Duplicate impressions were taken to assess reproducibility.

RESULTS

18 subjects had scorable sequences. Descriptive analyses showed erosive changes following acid consumption and reparative changes in the subsequent 24 h period. Comparing baseline replica to the 24 h replica, there were no significant differences (p=0.26) in tooth surface characteristics. Comparing the replica taken immediately following acidic challenge with the subsequent replicas at 2, 4, 7 and 24 h, showed clear reduction of erosive effects on the enamel surface at 2 h (p=0.02) and a highly significant reduction at 4, 7 and 24 h (p<0.001).

CONCLUSION

This methodology demonstrated the ability to follow the progression and recovery of early erosive enamel lesions over 24 h being accurate and reproducible. This study suggests enamel repair commences within 2 h following a substantial acidic challenge and is completed 4-24 h later. After 24 h, the tooth surface appeared visibly indistinguishable from the original tooth surface, suggestive of a recovery process occurring.

CLINICAL SIGNIFICANCE

Healthy erosive lifestyles often culminate in tooth wear. The time taken for enamel remineralisation following acidic challenge is unknown however, this study suggests the repair process is relatively slow following a substantial acidic challenge, and at least 4-24 h should elapse prior to further acidic consumption to allow for recovery.

Tooth wear and the role of salivary measures in general practice patients

OBJECTIVES

The goal of this study was to investigate the association between tooth wear and salivary measures in a random sample of patients from practices of dentist members of a practice-based research network.

MATERIALS AND METHODS

Patients completed a questionnaire on oral self-care, health, dietary habits, medications, and socio-demographic variables. Six salivary characteristics (consistency, resting salivary flow, resting salivary pH, stimulated salivary flow, stimulated salivary pH, and buffering capacity) were measured, and a dental examination included categorizing patients according to the dentist's judgment of the degree of tooth wear (i.e., none/minimal, some, or severe/extreme). Bivariate and multinomial logistic regression models were used to relate salivary characteristics and other factors to the outcome of tooth wear.

RESULTS

Data are reported from 1,323 patients (age range 16-97 years) from 61 practices. Patient age, gender, number of teeth, and perception of dry mouth were associated with tooth wear, but salivary and dietary factors were either weakly or not related.

CONCLUSIONS

The findings of this cross-sectional assessment suggest that using these salivary tests and dietary assessments in real-life clinical settings is unlikely to be useful in assessing tooth wear risk. Suggestions are offered about risk assessment for tooth wear.

CLINICAL RELEVANCE

Assessing a dental patient's risk of tooth wear using salivary measures and dietary assessments as described is not recommended for general dental practice until stronger evidence exists indicating its utility.