The aim of this paper was to study pH conditions between dental sites, taking account the presence of caries, calculus, and microbial composition and alkali production.One hundred 13-year-old Thai schoolchildren were recorded for caries experience (DMFT, DT), calculus, plaque, and gingivitis. Ex vivo urease activity was measured on 11, 26, 31, and 46 (distal aspect) with the rapid urease test and pH at baseline and after rinse with 0.25 % urea solution on mesial site in vivo. Interproximal plaque from contralateral teeth was microbiological analysed with the checkerboard technique.Thirty-four children were caries free. Plaque and calculus were abundant; all children showed a high resting plaque pH and the mandibular incisor showed significantly (p < 0.01) higher pH at baseline, max pH and AOC7.0 after urea challenge, ex vivo urease activity and calculus but lower caries experience than other teeth. A significant inverse correlation (p < 0.02) was found between caries frequency and ex vivo urease activity for tooth 11. Anaerobes predominated over streptococci, but no significant differences between dental sites were found.The study group had a high baseline plaque pH, in vivo and ex vivo urease activity, and calculus but low caries experience, which was best reflected in the lower incisor region.Urease activity and pH on site level may be important determinants for individuals at caries risk.
We have previously reported that minor gland and whole saliva flow rates and salivary proteins showed differences in individuals with primary Sjögren’s syndrome or head and neck radiation therapy, compared with controls (Eliasson et al., 2005). We now hypothesize that pH and number of acidogenic micro-organisms in dental plaque as well as saliva buffering capacity also differ in these individuals. Plaque pH was measured by the microtouch method up to 60 min after a sucrose rinse. Plaque collected from the same sites was analyzed for counts of total and acidic micro-organisms. Compared with their controls, the irradiated group but not the Sjögren’s syndrome group displayed significantly lower plaque pH, increased numbers of lactobacilli and Candida species, as well as reduced buffering capacity. Stepwise regression tests suggested that the buccal minor-salivary-gland secretion rate in the test groups and counts of mutans streptococci in the controls were of significant importance for dental plaque pH.
There is no report in examining dental plaque pH after dental care under general anesthesia. This study investigated the effects of comprehensive dental rehabilitation under general anesthesia on the oral environment of children with severe early childhood caries (S-ECC) and the influence of dental plaque pH on caries recurrence and salivary microflora. Thirty-seven children (mean age, 51.08 ± 9.68 months) with S-ECC who underwent comprehensive dental treatment under general anesthesia were selected. Caries index, plaque pH, and (SM) and (LB) counts were evaluated during the initial examination and 6-month and 12-month follow-ups. The plaque pH was significantly greater at the 6-month follow-up examination than at the initial examination (P = 0.006) and at the 12-month follow-up (P = 0.002), but there was no significant difference in plaque pH between the initial examination and the 12-month follow-up (P = 0.942). SM and LB counts at the sixth and twelfth months were significantly lower than the initial counts (P 0.05). The comprehensive dental rehabilitation under general anesthesia for children with S-ECC caused a temporary significant increase in the plaque pH at the sixth month and a significant reduction in the salivary microflora during the 12-month follow-up. Plaque pH did not demonstrate any strong correlations with caries status and salivary microflora in children with S-ECC.
Background: Complementary infant formulas are the second most important sources of nutrition for neonates after breast milk. Considering the cariogenic potential of infant formulas, selection of these nutritive sources should be safe to reduce the risk of baby bottle syndrome in newborns. The present study aimed to estimate the plaque pH changes after rinsing with four customary used types of complementary infant formula. Methods: An in-vivo, in-vitro study was conducted on five healthy neonates aged 12-18 months to assess the plaque pH changes caused by rinsing with four different types of complementary infant formula, including Rice and Milk Cerelac, Wheat and Milk Cerelac, Banana and Milk Humana, and Peach and Milk Humana. Data analysis was performed in SPSS version 17 using paired t-test to compare the pH changes associated with each formula. In all the statistical analyses, P-value of less than 0.01 was considered significant. Results: All the formulas significantly reduced the plaque pH to less than the pre-rinse pH. However, the plaque pH decreased to less than the critical pH level (
Introduction: Nowadays, thanks to improvements in fruit yoghurt tastes, more tendencies are seen in their consumption especially among children. Therefore, their cariogenicity evaluation as healthy snacks is important. The goal of this study was the assessment of the consumption effect of two kinds of Iranian fruit (apple) and plain yoghurts on dental plaque PH. Methods: In this experimental study, 10 healthy dentistry students were selected upon inclusion criteria. Plaque pH in the certain areas of the mouth was measured by microelectrode and digital pH meter. PH was measured at the baseline and intervals of 2, 5, 7, 10, 15, 20, 30, 40, 50 and 60 minutes after eating test products: fruit yoghurt (apple) and plain Yoghurt. For positive control group, just the baseline PH and at intervals of 2 and 5 min after swishing with 10% sucrose solutions were recorded. The results were analyzed using repeated measures ANOVA. Results: Lowest pH was obtained after fruit yoghurt consumption followed by plain yoghurt and %10 sucrose solution and the plaque PH difference was significant (P=0.05). Furthermore, time duration which remained below the critical pH was longer after consuming fruit yoghurt. Conclusion: Both kinds of yoghurts were considered cariogenic since plaque pH drop below critical points. Average of plaque pH after consuming fruit yoghurt was significantly lower in almost all the time intervals
With increased trend among people to choose a healthy diet, there is an increased consumption of health drinks by children. Thus, it is important to know their cariogenicity. To evaluate the effect of consumption of health drinks viz., Horlicks, Boost and Complan on plaque pH in children. The study consisted of four groups: Group I (control)- 10% sucrose solution, Group II- Horlicks, Group III- Boost, Group IV- Complan. Samples of plaque from representative teeth were collected and pH was measured using an electrode outside the mouth. After baseline pH was recorded, children were given their respective drinks and were asked to consume slowly over a period of three to five minutes following swish with 20 ml of the test drink for one minute. The pH was then recorded after 10, 20, 30, 40 and 60 minutes of the post consumption period. Obtained values were subjected to one-way ANOVA test for multiple group comparison followed by Post-Hoc Tukey's test for group wise comparison. Twenty minutes after consumption of Complan and Boost, pH was decreased, but not to the critical pH value as in case of sucrose. The pH was found to be slightly increased, 20 minutes post Horlicks consumption. Post 60 minutes consumption of all the drinks including sucrose solution, the pH was increased in comparison to post 20 minutes. However, 60 minutes post consumption of Boost and Horlicks, pH increased above the baseline. Consumption of health drinks viz., Complan and Boost did not lower the plaque pH to the level of critical pH. Consumption of Horlicks increased the plaque pH.
Introduction:Many different kinds of chewing gum can increase the flow of saliva, and they have been proven to have anti-bacterial effects as well. The aim of this study was to compare the effect of natural turpentine and synthetic sugar-free gums on dental plaque pH after a sucrose challenge. Methods: This randomized clinical trial was conducted on 15 subjects, who refrained from oral hygiene for two days and rinsed with 10% sucrose solution. Then for 30 minutes, they chewed one of three sugar-free gums: Van (natural), Orbit Complete, Orbit (synthetic), or one sugar-containing chewing gum (Banana). One group did not receive any gum (control group). Plaque pH was measured by the plaque sampling method before rinsing with sucrose, and 5, 10, 15, 20, and 30 minutes after chewing. Results: The lowest plaque pH drop was seen in the Orbit Complete group, and the highest was in the Banana group. The pH increased faster with Van and Orbit Complete gums. The plaque pH was more than baseline pH after 20 minutes in the Van and Orbit Complete groups (P
Mouthwashes are important means used in chemical control of dental plaque. There is strong evidence suggestive of better effectiveness, when fluoride is added to chlorhexidine mouthwash. To assess the anti-plaque efficacy of Chlorhexidine combined with Fluoride mouthwash and to measure its impact on plaque accumulation and on plaque pH. Initially 100 subjects were screened. A double blind, parallel randomized clinical trial was conducted on 30 subjects after applying inclusion and exclusion criteria. Other independent variables were matched before randomly allocating them in three groups: Group A-Chlorhexidine as positive control, Group B-Chlorhexidine + Fluoride as test group and Group C- Distilled water as negative control. Oral prophylaxis of participants was done before onset of the study. Plaque pH was assessed before and immediately after rinsing at 0, 5 and 10 minutes interval and after 7 days with digital pH electrode (pHepR pH meter, Hanna Instruments R10285) and accumulation of plaque was recorded by Turesky et al., modification of Quigley Hein Plaque Index (1970). ANOVA test was used for statistical analysis. Although there was a statistically significant reduction in mean plaque scores from baseline to seven days in both Groups A and B, Group B showed better anti-plaque efficacy . Almost equal drop in plaque pH was seen for both the groups at 5 and 10 minutes. Better anti-plaque efficacy was observed in Group B (Chlorhexidine and Fluoride combination) with minimum variation of plaque pH.
Abstract Objectives Previous research has shown that regular use of CPP–ACP increases calcium and inorganic phosphates in plaque and reduces enamel mineral loss. The aim of this study was to investigate if a CPP–ACP-containing paste would neutralize acidic challenges in dental plaque following sucrose rinse. Method Plaque pH was measured on 15 subjects in a cross-over study with and without prior application of the paste and with and without CPP–ACP. On each occasion, subjects rinsed with 10% sucrose and sorbitol solutions for 2 min in randomized order. Results The results showed the median lowest pH without paste was 4.8 (IQR: 4.7–5.0) and with mousse 5.6 (IQR: 5.5–5.6 and p < 0.001). The median lowest pH was 5.0 (IQR: 4.9–5.3) without CPP–ACP and with CPP–ACP was 5.8 (5.6–6.1 and p < 0.001). The time that pH remained below 5.7 and the time to return to resting pH showed similar differences in all subjects ( p < 0.01). Conclusion The results indicate that prior application of a CPP–ACP-containing paste reduced the fall in plaque pH following a sucrose challenge.