The effect of preprocedural mouthrinses against COVID-19 before acid etching on the microleakage of a resin-based sealant in permanent molars: An in vitro experimental study.

Aim: To determine whether rinsing with preprocedural mouthrinses against coronavirus disease before acid etching affects resin-based sealant microleakage. Materials and Methods: A presented in vitro experimental study was performed on 15 extracted permanent third molars. Samples were randomly allocated into five groups: Group 1-distilled water (control); Group 2-1% hydrogen peroxide; Group 3-1.5% hydrogen peroxide; Group 4-0.5% povidone-iodine; and Group 5-1% povidone-iodine. After the teeth were immersed in the assigned mouth rinses for 60 s, they were sealed with Concise™ white sealant. Subsequently, the teeth were thermocycled for 500 cycles, immersed in 2% methylene blue solution for 24 h, and sectioned with two parallel cuts in the buccolingual direction. Sixty surfaces (12 surfaces in each group) were examined for microleakage under a 40× light microscope and scored as described by Zyskind et al. Welch's one-way analysis of variance test and the Games-Howell test were used to analyze the results at a significance level of P < 0.05 for all tests. Results: The intergroup comparisons indicated that the 0.5% povidone-iodine group and the 1% povidone-iodine group had significantly higher microleakage compared with the control group. The 1% and 1.5% hydrogen peroxide groups demonstrated no significant difference in mean microleakage scores compared with the control group. There was no significant difference between the povidone groups and the hydrogen peroxide groups. Conclusions: Preprocedural rinsing with 0.5% and 1% povidone-iodine before acid etching caused higher microleakage of resin-based sealant, while hydrogen peroxide rinsing gave comparable microleakage compared with the control group.

The Remineralization Effect of Calcium Glycerophosphate in Fluoride Mouth Rinse on Demineralized Primary Enamel: An in vitro Study.

Aim: To evaluate the remineralization effect of a fluoride mouth rinse containing calcium glycerophosphate in fluoride mouth rinse based on the surface microhardness of demineralized primary enamel. Materials and Methods: 40 sound primary incisors were placed into self-curing acrylic resin and subjected to a demineralizing solution for 5 days, resulting in the formation of artificial caries. The teeth were categorized into four groups (n = 10): group I artificial saliva, group II sodium fluoride, group III sodium fluoride + sodium monofluorophosphate, and group IV sodium monofluorophosphate + calcium glycerophosphate. The specimens received a pH cycling procedure and were submerged twice in their assigned groups for 7 days. The baseline, after demineralization, and after remineralization surface microhardness values were determined. One-way analysis of variance (ANOVA) was used to analyze the mean surface microhardness between groups and one-way repeated measures ANOVA for the mean surface microhardness within each group and Bonferroni's for multiple comparisons at 95% confidence level. The percentage recovery surface microhardness was determined by calculating the average surface microhardness. Results: After demineralization, the mean surface microhardness in all groups significantly decreased. After remineralization, group I had the lowest surface microhardness values and the percentage recovery surface microhardness (P value < 0.001), and group IV had the highest surface microhardness values and the percentage recovery surface microhardness (P value < 0.001). No significant difference was found between groups II and III (P value = 0.365). Conclusions: Fluoride mouth rinse containing calcium glycerophosphate has a remineralization effect on demineralized primary enamel.

Remineralization Effect of Calcium Glycerophosphate in Fluoride Mouth Rinse on Eroded Human Enamel: An In Vitro Study.

Aims and Objectives: The aim of this in vitro study was to evaluate the remineralization effect of calcium glycerophosphate (CaGP) in fluoride mouth rinse on permanent enamel eroded by a soft drink. Materials and Methods: Forty sound permanent premolars were embedded in self-curing acrylic resin and immersed in Coca-Cola to create erosive lesions. The teeth were divided into four groups (n = 10): Group I artificial saliva; Group II sodium fluoride; Group III sodium fluoride + sodium monofluorophosphate; and Group IV sodium monofluorophosphate + CaGP. The specimens in the assigned groups underwent pH cycling for ten days. The baseline, after erosion, and after remineralization surface microhardness (SMH) values were determined. The data were analyzed by one-way analysis of variance (ANOVA). The mean SMH value between groups and one-way repeated measures ANOVA for the mean SMH value within each group and Bonferroni's for multiple comparisons at a 95% confidence level were determined. The average SMH was used and calculated as the percentage recovery of SMH. Results: After being eroded by the cola soft drink, the mean SMH values in all groups were significantly decreased. After remineralization, Group I had the lowest %SMHR. The %SMHR of Groups II, III, and IV were significantly higher than Group I (P < 0.001). However, there were no significant differences among Groups II, III, and IV (P > 0.05). Conclusions: Fluoride mouth rinse with and without CaGP showed similar efficacies in remineralizing eroded permanent enamel.

The Efficacy of Non-fluoridated Toothpastes on Artificial Enamel Caries in Primary Teeth: An In Vitro Study.

AIMS: The aim of this study was to evaluate the remineralizing effect among various non-fluoridated toothpastes on artificial caries in primary teeth. MATERIALS AND METHODS: Fifty sound primary incisor teeth were embedded in self-curing acrylic resin and immersed in demineralizing solution for 4 days forming artificial caries. All teeth were divided into five groups (10 teeth/group): Group I deionized water (control); Group II 1000 ppm F (Kodomo®); Group III non-fluoridated toothpaste containing calcium glycerophosphate and calcium lactate (Dokbuaku®); Group IV casein phosphopeptides-amorphous calcium phosphate (CPP-ACP) paste (GC Tooth Mousse®), and Group V non-fluoridated toothpaste containing nanohydroxyapatite (NHA) (Apagard®). The specimens were subjected to pH-cycling and immersed in toothpaste slurry twice for 7 days. Baseline, before, and after pH-cycling surface microhardness (SMH) values were measured by Vickers hardness numbers, and the percentage recovery of SMH (%SMHR) was calculated. Data were analyzed by one-way analysis of variance and Tukey's multiple comparison at 95% confidence intervals. RESULTS: The SMH values of test groups were significantly higher than those of the control group (p = 0.00). The %SMHR was -5.72±7.03% in the control group, Group II was significantly higher than Group III but there were no significant differences among Groups II, IV, and V (p > 0.05). CONCLUSION: Non-fluoridated toothpastes containing CPP-ACP or NHA for young children had efficacy in remineralizing effect on primary teeth comparable with 1000 ppm fluoridated toothpaste.

The effect of inferior alveolar nerve block anesthesia of 4% articaine and epinephrine 1:100,000 on blood flow and anesthesia of human mandibular teeth.

BACKGROUND/PURPOSE: Local anesthetics and anesthetic techniques affect the patterns of pulpal blood flow (PBF) and pulpal anesthesia in human teeth. This study aimed to determine PBF changes and pulpal anesthesia of intact mandibular first molars and canines after administration of 4% articaine with epinephrine 1:100,000 using inferior alveolar nerve block (IANB). MATERIALS AND METHODS: Ten healthy subjects received IANB of 4% articaine with epinephrine 1:100,000. Laser Doppler flowmetry and electrical pulp testing were combined to assess PBF changes and pulpal anesthesia of intact mandibular first molars and canines. The data were analyzed using one-way repeated-measures analysis of variance and Student-Newman-Keuls test. RESULTS: IANB with 4% articaine and epinephrine 1:100,000 did not have any significant change in PBF for the first 20 min post injection in mandibular first molars, and for 45 min post injection in the canines (P > 0.05). However, a hyperemic response occurred during 25-60 min post injection in the molars, and between 60 and 75 min post injection in the canines (P < 0.05). Thereafter, the PBF in both teeth returned to the baseline. Onset of pulpal anesthesia was 8.60 ±â€¯2.12 min in the molars, and 9 ±â€¯1.94 min in the canines. Duration of pulpal anesthesia was 82.40 ±â€¯41.56 min in the molars, and 84 ±â€¯47.40 min in the canines. CONCLUSION: In case of successful IANB, 4% articaine and epinephrine 1:100,000 caused insignificant changes in PBF up to 30 min but a hyperemic response at later time points. Thereafter, the PBF returned to the baseline.

The Effectiveness of Visual Pedagogy for Toothbrushing in Children with Autism Spectrum Disorder.

OBJECTIVES: The aim of this study was to evaluate toothbrushing effectiveness in children with mild and moderate levels of severity of autism spectrum disorder (ASD) after using visual pedagogy. MATERIALS AND METHODS: This quasi-experimental study was carried out with 30 children with ASD aged 5-17 years; 21 had mild ASD and 9 had moderate ASD. Informed consent and the subject's demographic information were obtained from caregivers. All subjects were then asked to show their toothbrushing practices, which were recorded by video. The toothbrushing ability, toothbrushing cooperation, and plaque index were evaluated before the study and at 2 weeks, 4 weeks, 3 months, and 6 months after visual pedagogy had been used. Results were analyzed by the Friedman test, Pearson's chi-square test, Fisher's exact test, and Mann‒Whitney U test. RESULTS: Toothbrushing ability was significantly improved at all periods of follow-up. Toothbrushing cooperation and the dental plaque index were significantly better than before the study at 4 weeks, 3 months, and 6 months of follow-up. The toothbrushing ability of subjects with mild ASD was significantly better than that of subjects with moderate ASD at 4 weeks and 6 months of follow-up. The toothbrushing cooperation of the mild group was significantly better than that of the moderate group at 2 weeks, 4 weeks, and 3 months. There was no statistically significant reduction in the plaque index between the two groups. CONCLUSION: Visual pedagogy is useful for improving toothbrushing effectiveness in children with mild or moderate severity ASD. However, children with moderate severity ASD take longer to improve.

Association of sensory sensitivities and toothbrushing cooperation in autism spectrum disorder.

BACKGROUND: Sensory over-responsivity (SOR) is common in autistic spectrum disorder (ASD), and it leads to a more intense response to sensory stimuli. AIM: To compare toothbrushing cooperation at home and in a dental office between SOR and sensory not over-responsivity (SNOR) children with ASD. DESIGN: This cross-sectional observational study was conducted with 51 children with ASD aged 4-17 years. Caregivers assessed each subject's sensory response by completing a back-translation questionnaire listing eight sensitivities. Subjects who had three or more of the sensitivities were considered SOR subjects. Toothbrushing cooperation in the dental office was recorded on videos. Statistical analysis used the Spearman correlation coefficient, chi-square test, Fisher's exact test, and Mann-Whitney U test. RESULTS: SNOR subjects (n = 10) had significantly higher scores in toothbrushing cooperation at home and in the dental office than did SOR subjects (n = 41) (P < .05). Oral sensitivity was significantly associated with toothbrushing cooperation at home, whereas oral, light, sound, and touch (face) sensitivities were significantly correlated with toothbrushing cooperation in the dental office (P < .05). CONCLUSIONS: SOR subjects showed less toothbrushing cooperation than SNOR subjects both at home and in the dental office.

The effect of selective carious tissue removal and cavity treatments on the residual intratubular bacteria in coronal dentine.

BACKGROUND/PURPOSE: The use of cavity treatments may help in the reduction of bacteria remaining in dentinal tubules after selective carious tissue removal. This study aimed to investigate the effect of selective carious tissue removal and treatment with either 35% phosphoric acid +0.12% chlorhexidine or dentine conditioner on the residual intratubular bacteria in coronal dentine of deep carious lesions. MATERIALS AND METHODS: Thirty carious human molars were randomly divided into three groups; group 1: untreated carious teeth (positive control), group 2: carious teeth treated with 35% phosphoric acid and chlorhexidine disinfectant after selective carious tissue removal and group 3: carious teeth treated with dentine conditioner after selective carious tissue removal. Another six non-carious teeth was used as negative control. The presence of bacteria and depth of bacteria remaining in dentinal tubules were determined by scanning electron microscopy (SEM). Chi square test and one-way, repeated-measures analysis of variance were used for statistical analysis. RESULTS: Using SEM, coronal dentine of group 1, 2 and 3 revealed cocci, rod and filamentous bacteria within dentinal tubules. Positive rates of bacteria detection in coronal dentine of group 1 were significant higher than those of group 2 and 3 (P < 0.05). The distance of bacteria remaining in the dentinal tubules in group 1, 2 and 3 were 1149.14 ±â€¯384.44, 707.98 ±â€¯357.19 and 869.25 ±â€¯470.75 µm, respectively. CONCLUSION: Both treatment groups had similar ability to reduce the number of intratubular bacteria in coronal dentine of carious teeth, but not complete elimination.

The effect of intraosseous local anesthesia of 4% articaine with 1:100,000 epinephrine on pulpal blood flow and pulpal anesthesia of mandibular molars and canines.

OBJECTIVES: The aim of this study was to determine the effect of intraosseous (IO) anesthesia with 4% articaine and 1:100,000 epinephrine on pulpal blood flow (PBF) and pulpal anesthesia of mandibular first molars and canines in human subjects. MATERIALS AND METHODS: Ten healthy volunteers with intact mandibular first molar and canine were given an osteocentral technique of IO injection using the Quick Sleeper 5 system and 4% articaine with 1:100,000 epinephrine at distal site of mandibular first molar. The PBF was monitored by a laser Doppler flowmeter (LDF). Pulpal anesthesia was assessed with an electric pulp tester (EPT). RESULTS: IO injection caused a decrease in PBF in molars from 6.31 ± 3.85 perfusion units (P.U.) before injection to 2.51 ± 2.53 P.U. 1 min after injection (P < 0.001). The percentage reduction in PBF was 60% after 1 min and PBF returned back to the baseline after 45 min. No significant reduction in PBF was observed in the canines (P = 0.212). For pulpal anesthesia in the molars, the mean onset was 2.40 ± 0.84 min and the mean duration was 38 ± 16.19 min. In the canines, there was a decrease in the sensitivity to EPT but complete pulpal anesthesia was not achieved. CONCLUSIONS: IO injection distal to mandibular first molar caused a decrease in PBF and successful pulpal anesthesia in first molar, but not in canine. Both PBF and EPT readings returned to normal, suggesting that pulpal ischemia may not occur. CLINICAL RELEVANCE: IO anesthesia is safe to use as a primary technique in teeth with normal pulp.

ENHANCING REMINERALIZATION OF PRIMARY ENAMEL LESIONS WITH FLUORIDE DENTIFRICE CONTAINING TRICALCIUM PHOSPHATE.

Fluoride dentifrice is effective in preventive dental caries but may cause fluorosis, especially in young children. Reducing the concentration of fluoride from the regular concentration of 1,000 parts per million (ppm) to 500 ppm can reduce the risk for fluorosis but increases the risk of caries. Adding tricalcium phosphate (TCP) to the dentifrices may improve the efficacy of remineralization possibly allowing for a lower concentration of fluoride to reduce the risk of fluorosis. We studied this to inform future caries prevention efforts in children. We immersed 40 sound primary incisors into demineralizing solution (pH=4.4) for 96 hours at 37°C to create demineralized lesions. The 40 teeth were then divided into 4 groups of 10 teeth each. Group A: control (treated with deionized water only); Group B: treated with fluoride dentifrice at a concentration of 1,000 ppm; Group C: treated with fluoride dentifrice at a concentration of 500 ppm and 500 ppm TCP, and Group D: treated with fluoride dentifrice at a concentration of 1,000 ppm and 500 ppm TCP. The teeth were each subjected to 7 days of pH-cycling and the studied dentifrice was applied for one minute, 3 times daily during the 7 day period. After the 7 day period the teeth were each sectioned and examined with polarized light microscopy. The depths of demineralized areas were measured using Image-Pro plus software. A pair t-test was used to compare lesion depths before and after dentifrice treatment. Differences in mean lesion depths within each group were analyzed using the One-way ANOVA and LSD tests; a 95% confidence intervals were calculated. The mean lesion depths in all the groups before dentifrice treatment were not significantly different (p=0.143). The mean demineralized lesion depths after dentifrice treatment were significantly different by group (p=0.00). The mean demineralized lesion depth in Group A significantly deeper than the other groups (p=0.00). Group D had the shallowest depth, significantly shallower than the other groups (p=0.006). There was no significant difference in the mean demineralized lesion depth between Groups B and C (p=0.478). The mean demineralized lesion depth changed significantly after dentifrice treatment in all the groups (p=0.00). Group A was significantly deeper (p=0.00) and groups B, C and D were all significantly shallow. Group D had the greatest reduction in mean demineralized lesion depth (p<0.05). The 1,000 ppm fluoride plus TCP dentifrice gave superior remineralization than the 500 ppm fluoride plus TCP and the 1,000 ppm fluoride dentifrice. The 500 ppm fluoride plus TCP gave the same remineralizing effect as the 1,000 ppm fluoride dentifrice. TCP enhances remineralization on primary enamel when added to fluoride dentifrice. Our results show if TCP is added to fluoride dentifrice a lower concentration of fluoride is needed to provide the same benefit as fluoride dentifrice with a higher concentration of fluoride, reducing the risk of fluorosis in children.

The efficiency of child formula dentifrices containing different calcium and phosphate compounds on artificial enamel caries.

OBJECTIVES: Fluoride toothpaste has been extensively used to prevent dental caries. However, the risk of fluorosis is concerning, especially in young children. Calcium phosphate has been an effective remineralizing agent and is present in commercial dental products, with no risk of fluorosis to users. This in vitro study aimed to compare the effects of different calcium phosphate compounds and fluoride-containing dentifrices on artificial caries in primary teeth. MATERIALS AND METHODS: Fifty sound primary incisors were coated with nail varnish, leaving two 1 mm2 windows on the labial surface before immersion in demineralizing solution for 96 hours to produce artificial enamel lesions. Subsequently, one window from each tooth was coated with nail varnish, and all 50 teeth were divided into five groups (n = 10); group A - deionized water; group B - casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (Tooth Mousse); group C - 500 ppm F (Colgate Spiderman®); group D - nonfluoridated toothpaste with triple calcium phosphate (Pureen®); and group E - tricalcium phosphate (TCP). Polarized light microscopy and Image-Pro® Plus software were used to evaluate lesions. RESULTS: After a 7-day pH-cycle, mean lesion depths in groups A, B, C, D, and E had increased by 57.52 ± 10.66%, 33.28 ± 10.16%, 17.04 ± 4.76%, 32.51 ± 8.99%, and 21.76 ± 8.15%, respectively. All data were processed by the Statistical Package for the Social Sciences (version 16.0) software package. Comparison of percentage changes using one-way analysis of variance and Fisher's least squares difference tests at a 95% level of confidence demonstrated that group A was significantly different from the other groups (P < 0.001). Lesions in groups B and D had a significant lesion progression when compared with groups C and E. CONCLUSIONS: All toothpastes in this study had the potential to delay the demineralization progression of artificial enamel caries in primary teeth. The fluoride 500 ppm and TCP toothpastes were equal in the deceleration of enamel caries progression and better than CPP-ACP paste and TCP toothpaste.

COMPARISON OF CHILDREN'S FOLLOW-ON INSTANT POWDERED COW'S MILK FORMULA, BUFFALO MILK FORMULA AND CHICKEN-BASED FORMULA ON ENAMEL MICROHARDNESS OF BOVINE TEETH IN VITRO.

Dental caries are a major public health problem worldwide. The aim of this study was to compare the effects of children's follow-on instant powdered cow's milk formula, buffalo milk formula and a chicken-based formula on microhardness of bovine enamel with artificial caries-like lesions. Forty bovine teeth were each placed in acrylic blocks and the enamel surfaces were polished to create flat 5 x 5 millimeter surfaces. The teeth surfaces were then demineralized using 0.1M lactic acid (pH 4.5) to achieve an enamel microhardness of 35-65 Vickers Hardness Numbers (VHN). All specimens were then randomly allocated into one of 4 groups (n=10/group). For remineralization, each group was soaked in a different kind of milk formula for 2 hours at 37°C except group 1 which was a negative control (artificial saliva) group. Group 2 was soaked in Murrah™ buffalo milk formula (a positive control ), group 3 in S-26-Promil-Gold™ (cow's milk formula) and group 4 in a chicken-based formula (Siriraj Hospital, Mahidol University). The microhardness of the specimens was then measured again. Data were analyzed using a one-way ANOVA and paired t-test with a 95% confidence interval. After exposure to the formula, the mean VHN for each study group was significantly higher (paired t-test, p < 0.05) except for group 1 (p = 0.345). The mean VHN for the the Murrah™ buffalo milk formula, the chicken-based formula and the S-26-Promil-Gold™ formula group were not significantly different from each other (one-way ANOVA, p > 0.05). In conclusion, S-26-Promil-Gold™ follow-on cow milk formula, Murrah™ buffalo milk formula and the chicken-based formula all increased bovine enamel microhardness after soaking for 2 hours.

FLUORIDE CONTENT OF COMMERCIALLY AVAILABLE SOY MILK PRODUCTS IN THAILAND.

Abstract. In Thailand, the consumption of soy milk products is common but there is limited data about their fluoride content. The purpose of this study was to es- timate the fluoride content of soy milk products available in Thailand. Fluoride content was determined for 76 brands of soy milk using a F-ion-specific electrode. The fluoride concentrations ranged from 0.01 to 3.78 µg/ml. The fluoride content was not related to sugar content, soy bean content or the sterilization process. Among 3 brands of soy milk containing tea powder extract, the fluoride content was high (1.25 to 3.78 µg/ml). Most brands of soy milk tested in our study had fluoride content below the optimal daily intake but brands containing tea powder extract if consumed by children may increase their risk for fluorosis.

A 3-MONTH STUDY OF FLUORIDE RELEASE FROM DIFFERENT CALCIUM PHOSPHATE FLUORIDE VARNISHES ON PRIMARY TEETH.

A range of dental varnishes containing several calcium and phosphate compounds in addition to fluoride to promote remineralization have recently been commercialized. However, the fluoride varnish in the presence of calcium and phosphate can react to form relative poorly soluble phases and its bioavailability. Most of previous studies have focused on fluoride release over a short period. The purpose of this in vitro study was to evaluate the fluoride release from different fluoride varnishes on primary teeth during 3 months. Twenty-five sound primary incisors were randomly divided into five groups: Group A-control group (no treatment), Group B - 5% sodium fluoride varnish (5%NaF)(Duraphat®), Group C-5% sodium fluoride plus tricalcium phosphate varnish (5%NaF+TCP)(ClinproTM White), Group D- 5% sodium fluoride plus amorphous calcium phosphate varnish (5%NaF+ACP)(Enamel Pro®), and Group E-5% sodium fluoride plus tricalcium phosphate varnish (5%NaF+TCP)(Mahidol). The samples were then immersed in artificial saliva at room temperature until used. The concentration of fluoride released was measured with F-ion-specific electrode at 2, 4, 8, 12, 24, and 48 hours and then weekly for three months. To analyze the results, we used the one-way ANOVA and Tukey's multiple comparison tests at a 95% level of confidence. Group E had the greatest initial fluoride release within the first 24 hours and Group B had the lowest initial release fluoride of the treatment groups. Group B had a slower rate of decline in fluoride release over time than the other treatment groups. By 3 months, the varnishes with the highest to the lowest release of fluoride were Group B=C>E>D>A. All the treatment samples released more fluoride than the control group. Duraphat®(5%NaF) and Clinprotm(5%NaF+TCP) had the highest release of fluoride at 3-month evaluation. The TCP fluoride varnish released more fluoride than the ACP fluoride varnish by 3 months.

FLUORIDE CONTENT OF COMMERCIALLY AVAILABLE BOTTLED DRINKING WATER IN BANGKOK, THAILAND.

The use of bottled drinking water may be a source of fluoride and could be a risk factor for fluorosis among infants and young children. The aim of this study was to evaluate the fluoride content of commercially available bottled drinking water in Bangkok, Thailand. Forty-five water samples (15 samples of plain water and 30 samples of mineral water) were purchased from several supermarkets in Bangkok, Thailand. Three bottles of each water sample were purchased, and the fluoride content of each sample was measured twice using a combination fluoride-ion selective electrode. The average reading for each sample was then calculated. Data were analyzed by descriptive statistics. Differences between mineral and plain water samples were determined by Student's t-test. The mean (±SD) fluoride content for all the water samples was 0.17 (±0.17) mg F/l (range: 0.01-0.89 mg F/l). Six brands (13%) tested stated the fluoride content on the label. The actual fluoride content in each of their brands varied little from the label. Eight samples (18%) had a fluoride content >0.3 mg F/l and two samples (4%) had a fluoride content >0.6 mg F/l. The mean mineral water fluoride concentration was significantly higher than the mean fluoride concentration of plain water (p=0.001). We found commercially sold bottled drinking water in Bangkok, Thailand contained varying concentrations of fluoride; some with high concentrations of fluoride. Health professions need to be aware this varying fluoride content of bottled drinking water and educate the parents of infants and small children about this when prescribing fluoride supplements. Consideration should be made to have fluoride content put on the label of bottled water especially among brands with a content >0.3 mg F/l.

EFFECT OF ADDING TRICALCIUM PHOSPHATE TO FLUORIDE MOUTHRINSE ON MICROHARDNESS OF DEMINERALIZED PRIMARY HUMAN TOOTH.

The purpose of the present study was to evaluate the effect of fluoride mouthrinse containing tricalcium phosphate on microhardness of demineralized primary enamel. Thirty-six sound primary incisors were immersed in a demineralizing solution (pH 4.4) for 96 hours at 37 degrees C to create artificial caries-like lesions. After artificial caries formation, the specimens were randomly divided into 3 groups (with 12 specimens in each group): Group A: deionized water; Group B: 0.05% NaF plus 20 ppm tricalcium phosphate mouthrinse and Group C: 0.05% NaF mouthrinse. All the specimens were immersed for 1 minute at 37 degrees C three times per day for 7 days in the respective mouthrinse among pH cycling. The surface microhardness was examined using a Vickers hardness tester (100 grams for 15 seconds) at baseline, before and after the pH-cycling procedure. Data were analyzed using one-way ANOVA and Tukey's multiple comparison tests with a significance level of 0.05. After treatment, Group Ahad a significantly lower surface microhardness value than the other two groups (p=0.000); however, there was no significant difference between Groups B and C (p=0.728). We concluded fluoride mouthrinse containing tricalcium phosphate and fluoride mouthrinse have similar remineralizing effects on microhardness of demineralized primary teeth.

EFFICACY OF FLUORIDE MOUTHRINSE CONTAINING TRICALCIUM PHOSPHATE ON PRIMARY ENAMEL LESIONS: A POLARIZED LIGHT MICROSCOPIC STUDY.

The aim of this study was to evaluate the effect of fluoride mouthrinse containing tricalcium phosphate (TCP) on remineralization of primary teeth enamel lesions compared with fluoride mouthrinse alone to determine if the addition of TCP gives additional benefit. Thirty-six sound primary incisors were immersed in a demineralizing solution (pH 4.4) for 96 hours at 37°C to create demineralized lesions. After artificial caries formation, the specimens were randomly assigned to one of three groups (n = 12): Group A: deionized water; Group B: 0.05% sodium fluoride (NaF) plus 20 ppm tricalcium phosphate mouthrinse and Group C: 0.05% sodium fluoride (NaF) only mouthrinse. A pH-cycling process was carried out for 7 days at 37°C. During pH-cycing, all the specimens were immersed for 1 minute; 3 times a day, in the respective mouthrinse. The specimens were then evaluated by polarized light microscopy with the computerized Image Pro Plus program. Data were analyzed using paired-t, one-way ANOVA and Tukey's multiple comparison tests at a 95% level of confidence. The depth of the lesions were significantly different between pre- and post-treatment for all groups (p = 0.00). The lesion depth in the Group A (control) increased by 102% (±15), in Group B by 34% (±12) and Group C by 36% (±9). The lesion depths differed significantly between the control (Group A) and treatment groups (Group B,C) (p < 0.05). Group A had a significantly greater increase in lesion depth compared to the other groups. There was no significant difference in the percent change in lesion depths between Groups B and C. We concluded that the fluoride mouthrinse containing tricalcium phosphate provides no additional benefit over the mouthrinse containing fluoride alone.

Effects of the iontophoresis of lignocaine with epinephrine into exposed dentine on the sensitivity of the dentine in man.

OBJECTIVE: To determine the effects of the iontophoretic application of lignocaine and epinephrine to exposed dentine on the sensitivity of the dentine in human subjects. DESIGN: The experiments were carried out on 13 healthy premolars (13 subjects) that were scheduled for extraction. Dentine was exposed at the tip of the buccal cusp by cutting a cavity which was etched with 35% phosphoric acid. The sensitivity of the dentine was tested with probing and air blast stimuli. The subject indicated the intensity of any pain produced with a score of 0-100. In 7 teeth, the cavity was filled with a solution containing 20% (w/v) lignocaine HCl and 0.1% (w/v) epinephrine HCl, and an iontophoretic current of 120 µA was passed for 90s. The sensitivity of the dentine was tested before and immediately after the treatment and then at 10 min. intervals for 40 min. Pulpal blood flow was recorded at each stage. Control experiments were carried out on 6 teeth using a solution containing only the epinephrine. RESULTS: The lignocaine plus epinephrine solution completely blocked the pain produced by both forms of stimulus immediately, and this continued for at least 40 min. It also produced an immediate fall in pulpal blood flow that also lasted for at least 40 min. The epinephrine solution had the same effect on pulpal blood flow but no effect on dentine sensitivity. CONCLUSIONS: The topical application of 20% lignocaine and 0.1% epinephrine, with an iontophoretic current of 120µA for 90s, will anaesthetize exposed, normal, dentine.

The iontophoresis of lignocaine with epinephrine into carious dentine for pain control during cavity preparation in human molars.

OBJECTIVE: To determine the effectiveness of the iontophoretic delivery of lignocaine with epinephrine through carious dentine for pain control during cavity preparation. DESIGN: The experiments were carried out on 56 carious molars that required class I restorations in 42 subjects (aged 15-20 years). The overhanging enamel and soft caries were removed then the sensitivity of the exposed dentine was tested with drilling, probing and air blast stimuli. The subject indicated the intensity of any pain produced by marking a visual analogue scale (VAS). The cavity was then filled with 20% w/v lidocaine with 0.1% w/v epinephrine and a 200 µA iontophoretic current applied for 2 min after which the sensitivity of the dentine was re-tested. If the dentine was not anaesthetized, the treatment and testing were repeated up to 6 times. RESULTS: The total duration (min) of iontophoresis required to anaesthetize the dentine was: 2 in 7 teeth, 4 in 17 teeth, 6 in 14 teeth, 8 in 4 teeth, and 10 in 7 teeth. The remaining 7 teeth were not anaesthetized even after 14 min of iontophoresis. CONCLUSIONS: The iontophoretic delivery of lignocaine with epinephrine anaesthetized dentine for cavity preparation in 49 of 56 (87.5%) of carious molars.

Effect of fluoride varnishes containing tri-calcium phosphate sources on remineralization of initial primary enamel lesions.

The aim of this study was to evaluate the effect of fluoride varnishes containing tri-calcium phosphate on remineralization of primary enamel lesions. Forty-eight sound primary incisors were coated with nail varnish, leaving two 1 x 1 mm windows before being placed in a demineralizing solution for four days. After demineralization, all the specimens were coated with nail varnish over one of the windows and were randomly assigned to one of four groups: Group A: deionized water; Group B: Duraphat Fluoride Varnish; Group C: Clinpro White Varnish; Group D: TCP-fluoride varnish. Polarized light microscopy was used to evaluate initial lesion depth and after a 7-day pH cycle. Lesion depth was measured using a computerized method with the Image-Pro Plus Program. The differences in mean lesion depths were compared among the groups using the One-Way ANOVA and Tukey's multiple comparison tests at a 95% confidence interval. Group A had a significant increase in lesion depth compared to the other groups. No significant differences were found among Groups B, C and D. We concluded fluoride varnishes containing tri-calcium phosphate inhibit progression of initial primary enamel lesions, and the brands tested were not significantly different from each other in efficacy.