Factors associated with prevalence and severity of erosive tooth wear in patients with reflux oesophagitis.

BACKGROUND: Extrinsic factors for erosive tooth wear (ETW) have been widely reported, but the intrinsic factors for wear remain unclear. OBJECTIVES: The aim of this study was to evaluate the factors associated with the prevalence of ETW in patients with reflux oesophagitis (RO). To prevent severe ETW with RO, factors associated with severity of ETW were also evaluated. METHODS: A total of 270 patients with RO were recruited. A modified tooth wear index was used to evaluate the prevalence and severity of ETW. Salivary secretion and buffering capacity were assessed prior to endoscopy. Subjects were asked to complete a medical condition and oral self-care questionnaire. Univariate and multivariate analyses were employed to identify factors collectively associated with the prevalence and severity of ETW. RESULTS: A total of 212 cases were categorized as patients with ETW (148 with mild ETW and 64 with severe ETW). Multivariate analyses indicated that saliva secretion, severity of RO and proton pump inhibitor (PPI) resistance were associated with the prevalence of ETW, whereas age, BMI and severity of RO were associated with the severity of ETW. The odds ratio of saliva secretion and BMI were less than 1, meaning that higher saliva secretion resulted in a lower prevalence of ETW and lower BMI was associated with severe ETW. CONCLUSION: Saliva secretion, severity of RO and PPI resistance were associated with the prevalence of ETW, whereas age, BMI and severity of RO were associated with the severity of ETW. Lower saliva secretion and BMI were significant factors for ETW.

In females, salivary secretion was significantly lower in patients with severe reflux esophagitis than in healthy controls.

BACKGROUND: The salivary secretion in patients with mild reflux esophagitis (RE) and non-erosive reflux disease is significantly lower in females, but not in males. However, sex differences in salivary secretion in patients with severe RE remain unknown. Therefore, the present study investigated sex differences in saliva secretion in patients with severe RE. METHODS: Subjects consisted of 23 male patients with severe RE, 24 male healthy controls (HCs), 26 female patients with severe RE, and 25 female HCs. Saliva secretion was assessed as follows: each patient chewed sugarless gum for 3 min prior to endoscopy, and the amount and pH of saliva secreted before and after acid loading as an index of the acid-buffering capacity were measured. RESULTS: In males, no significant differences were observed in the amount of saliva secretion, salivary pH, or the acid-buffering capacity between severe RE patients and HCs. In females, the amount of saliva secretion (severe RE: 2.4 [1.8-4.1], HCs: 5.3 [3.4-7.5], p = 0.0017), salivary pH (severe RE: 7.0 [6.7-7.3], HCs: 7.2 [7.1-7.3], p = 0.0455), and the acid-buffering capacity (severe RE: 5.9 [5.3-6.2], HCs: 6.2 [6.1-6.5], p = 0.0024) were significantly lower in severe RE patients than in HCs. CONCLUSION: Among females, the salivary secretion was significantly lower in severe RE patients than in HCs. This reduction in salivary secretion may contribute to the pathophysiology of severe RE in females.

Patients with gastroesophageal reflux disease (both reflux oesophagitis and non-erosive reflux disease): Prevalence and severity of erosive tooth wear and saliva properties.

BACKGROUND: The prevalence between erosive tooth wear (ETW) in association with reflux oesophagitis (RO) has been reported. However, the severity of both diseases and the relationship between ETW and non-erosive reflux disease (NERD) is unclear. OBJECTIVES: The prevalence and severity of ETW were investigated in RO, NERD and healthy controls. METHODS: 135 patients with RO, 65 with NERD and 40 healthy controls were recruited for this case-control study. A modified tooth wear index was used to evaluate the prevalence and severity of ETW. Salivary secretion and buffer capacity were assessed prior to endoscopy. The prevalence and severity of ETW, saliva properties among each group were analysed using Pearson's chi-squared test. RESULTS: A total of 135 cases (56.3%) were categorised as the patient with ETW (55 with mild RO, 49 with severe RO and 31 with NERD). There was a significant relationship between the prevalence of RO and ETW, while there was no significant correlation between the prevalence of NERD and ETW. There was a significant difference related to the severity between RO and ETW. For salivary secretion, there was a significant difference between with and without ETW in patients with mild RO, severe RO and NERD. There was a significant difference between with and without ETW for salivary buffer capacity in patients with mild and severe RO. CONCLUSION: There was a significant association of the prevalence and severity between RO and ETW. Clinical signs such as ETW and salivary buffer capacity depended on the severity of RO.

Saliva Secretion Is Significantly Lower in Female Patients with Mild Reflux Esophagitis than in Female Healthy Controls.

INTRODUCTION: Saliva secretion is significantly lower in patients with mild reflux esophagitis than in healthy controls. A previous study on healthy controls showed that stimulated saliva secretion was lower in females than in males. Saliva secretion may be lower in female patients with mild reflux esophagitis than in male patients. Therefore, the present study investigated sex differences in saliva secretion in patients with mild reflux esophagitis. METHODS: Twenty-five male patients with mild reflux esophagitis, 25 male healthy controls, 24 female patients with mild reflux esophagitis, and 24 female healthy controls were recruited for this case-control study. Saliva secretion was assessed as follows: each patient chewed sugar-free gum for 3 minutes prior to endoscopy, and the volume and pH of saliva before and after acid loading as an index of the acid-buffering capacity were measured. RESULTS: No significant differences were observed in the amount of stimulated saliva secretion, salivary pH, or the acid-buffering capacity between male patients with mild reflux esophagitis and healthy controls. No significant differences were noted in salivary pH between female patients with mild reflux esophagitis and healthy controls; however, the amount of stimulated saliva secretion was significantly lower (p = 0.0023) in the former (2.5 [1.9-4.1]) than in the latter (4.6 [3.2-6.6]), while the acid-buffering capacity was slightly lower (p = 0.0578) in the former (5.9 [5.7-6.2]) than in the latter (6.2 [6.0-6.5]). CONCLUSION: The amount of stimulated saliva secretion was significantly lower in female patients with mild reflux esophagitis than in female healthy controls. This reduction in saliva secretion may affect the pathophysiology of mild reflux esophagitis in females.

Differences in salivary secretion and epidermal growth factor concentrations in mild reflux esophagitis and non-erosive reflux disease.

BACKGROUND: Sex differences in salivary secretion have been reported among healthy subjects. In the present study, salivary secretion and salivary epidermal growth factor (EGF) concentrations were investigated in mild reflux esophagitis patients, non-erosive reflux disease (NERD) patients, and healthy controls by matching the sex ratio. METHODS: Thirty-three (male:female = 11:22) patients with NERD, 33 (11:22) with mild reflux esophagitis, and 33 (11:22) healthy controls were recruited for this case-control study. Salivary secretion was assessed as follows: each patient chewed sugar-free gum for 3 min prior to endoscopy, and the amount of saliva secretion, salivary pH, and salivary pH after acid loading as an index of the acid-buffering capacity were measured. Salivary EGF concentrations were measured by ELISA. RESULTS: No significant differences were observed in the amount of saliva secretion, salivary pH, or the acid-buffering capacity between the mild reflux esophagitis and NERD groups. However, the amount of saliva secretion and the acid-buffering capacity in the mild reflux esophagitis group and the amount of saliva secretion, salivary pH, and the acid-buffering capacity in the NERD group were significantly lower than those in the healthy control group. No significant differences were noted in salivary EGF concentrations between the mild reflux esophagitis and NERD groups. CONCLUSION: After matching the sex ratio, the saliva secretion was significantly lower in patients with mild reflux esophagitis and NERD than in healthy controls. However, no significant differences were observed in the amount of saliva secretion or salivary EGF concentrations between both groups.

Proton Pump Inhibitor Treatment Has Little Effects on Secretion of Saliva in Patients with Proton Pump Inhibitor-Responsive Mild Reflux Esophagitis and Non-Erosive Reflux Disease.

INTRODUCTION: The secretion of saliva, which is triggered by acid reflux into the esophagus via the esophagosalivary reflex, plays a crucial role in the defensive mechanisms of the esophagus. The volume of saliva secreted in patients with gastroesophageal reflux disease (GERD) is reduced. However, the effects of proton pump inhibitors (PPI) on the secretion of saliva have rarely been reported. Therefore, the present study investigated changes in the volume and pH of saliva after the cessation of PPI. MATERIALS AND METHODS: We retrospectively reviewed the records of consecutive patients previously diagnosed with mild reflux esophagitis (RE) or non-erosive reflux disease (NERD) controlled with PPI (including vonoprazan) who performed the salivary secretion test before and after a 2-week cessation of PPI. The volume, pH, and pH after acid loading (buffering capacity) of saliva were compared before and after the cessation of PPI. RESULTS: Thirty-two patients (25 NERD, 7 mild RE) were included. The second saliva test was performed a median interval of 14 months [12.0-15.3] after the first test. No significant differences were observed in the volume of saliva secreted before and after the cessation of PPI (before 4.0 mL [2.7-6.0] vs. after 4.0 mL [2.3-5.9], p = 0.894). No significant differences were noted in pH or changes in pH after acid loading before and after the cessation of PPI (pH: before 7.1 ± 0.24 vs. after 7.0 ± 0.24, p = 0.1. Delta pH after acid loading: before 1.0 [0.8-1.2] vs. after 1.0 [0.8-1.2], p = 0.844). CONCLUSION: The cessation of PPI did not appear to affect the volume, pH, or buffering capacity of saliva in patients with PPI-responsive mild RE and NERD.

Evidence-based clinical practice guidelines for gastroesophageal reflux disease 2021.

In Japan, with the increasing prevalence of gastroesophageal reflux disease (GERD) and growing public interest, the Japanese Society of Gastroenterology issued Evidence-based Clinical Practice Guidelines for GERD (1st edition) in 2009 and a revised 2nd edition in 2015. A number of studies on GERD were subsequently conducted in Japan and abroad, and vonoprazan, a potassium-competitive acid blocker (P-CAB), became available for the first time in Japan in February 2015. The revised 3rd edition (Japanese edition), which incorporates new findings and information, was published in April 2021. These guidelines are summarized herein, particularly sections related to the treatment of GERD. The important clinical issues addressed in the present revision are (i) the introduction of treatment algorithms that classify GERD into reflux esophagitis and non-erosive reflux disease, (ii) the clarification of treatment algorithms based on to the severity of reflux esophagitis, and (iii) the positioning of vonoprazan in the treatment for GERD. The present guidelines propose vonoprazan as the initial/maintenance treatment for severe reflux esophagitis. They also recommend vonoprazan or PPI as an initial treatment for mild reflux esophagitis and recommended PPI and proposed vonoprazan as maintenance treatment. These updated guidelines offer the best clinical strategies for GERD patients in Japan and hope that they will be of global use for the diagnosis and treatment for GERD.

Saliva secretion is reduced in mild reflux esophagitis patients.

BACKGROUND: Salivary secretion in patients with mild reflux esophagitis has not been examined. In this study, saliva secretion and salivary epidermal growth factor (EGF) in patients with mild reflux esophagitis were investigated. METHODS: Thirty-eight mild reflux esophagitis patients and 38 control subjects were recruited for this case-control study. Saliva secretion testing was performed. Saliva secretion was assessed as follows: each patient chewed sugar-free gum for 3 min prior to endoscopy, and the volume and pH of saliva before and after acid loading as an index of the acid-buffering capacity were measured. The salivary EGF concentration was assessed by ELISA. RESULTS: The volume of saliva secreted was significantly (p = 0.0412) lower in the mild reflux esophagitis group than in the control group, with medians (25th-75th percentile) of 4.2 mL/3 min [2.6-6.2] and 6.0 [3.9-8.0], respectively. No significant differences were observed in salivary pH (the mild reflux esophagitis group: 7.1 [6.9-7.2], the control group 7.2 [7.1-7.3]). Salivary pH after acid loading was significantly (p = 0.0009) lower in the mild reflux esophagitis group (5.9 [5.5-6.3]) than in the control group (6.3 [6.2-6.5]). No significant differences were noted in salivary EGF concentrations (the mild reflux esophagitis group: 1739.0 pg/mL [1142.3-3329.0], the control group: 1678.0 [1091.8-2122.5]. CONCLUSION: The secretion volume and acid-buffering capacity of stimulated saliva were reduced in patients with mild reflux esophagitis.

Surface analysis of dental caries using a wireless pH sensor and Raman spectroscopy for chairside diagnosis.

A chairside tool for quantitative analysis of dental caries would improve clinical dental inspections. The wireless caries sensing tool with dental-explorer size has been developed comparing two sensing methods, Raman reading and pH reading for evaluating dental caries. The Raman spectra at 575 cm-1 and 960 cm-1 for in inorganic compounds, as well as 1450 cm-1 and 2940 cm-1 for organic compounds reinforced and supported the pH results. An Iridium/Iridium oxide (Ir/IrOx) pH sensing probe and wireless pH sensor (comprising an ESP8266 ESP-01 wireless module and ADS1115 analog digital converter) has been developed to quantitatively evaluate dental caries. All the operations of the wireless pH sensor were performed with a developed LabVIEW-based real-time data monitoring program. The slope and the linear fitting regression value (R2) of the wireless pH sensor using seven standards were -54.9 mV/pH and 0.999, respectively, showing high accuracy and stability for the pH measurements. The pH on the dental caries surface was measured with the wireless pH sensor, and the pH mapping results in the non-caries and caries areas were 6.9 and 5.7, respectively. The developed wireless pH sensor would be useful to understand the condition of dental caries and support dentists' inspection to remove only the caries part while keeping the non-caries structure.

The prevalence of non-carious cervical lesions (NCCLs) with or without erosive etiological factors among adults of different ages in Tokyo.

OBJECTIVES: To evaluate the prevalence of non-carious cervical lesions (NCCLs) on teeth with or without erosive etiological factors across a broad range of ages of Japanese adults. MATERIALS AND METHODS: The study sample consisted of a total of 1108 subjects aged 15 to 89 years in Tokyo, Japan. Two examiners evaluated NCCLs and dental erosion (DE) during a full-mouth examination. Subjects were asked to complete a self-administered daily diet, habits, and health condition questionnaire. Subjects who had frequent acid consumption or gastric reflux and at least one tooth with initial enamel wear were placed in the erosion present (EP) group, and the remainder of subjects were placed in the erosion not present (EN) group. Logistic regression analyses were carried out to identify etiological factors of NCCLs associated with DE. RESULTS: Overall prevalence of NCCLs was 60.2%; the prevalence increased with age. There were no statistical differences in the prevalence of NCCLs between the EP and EN groups, except for the 60-69 years group. Multiple logistic regression analysis showed the frequency of consumption of carbonated soft drinks, citrus juice, and acidic fruits such as oranges; tooth brushing pressure; and bruxism were associated with the presence of NCCLs. CONCLUSION: There were no statistical differences in the prevalence of NCCLs with or without erosive etiological factors except for the 60-69 years group. CLINICAL RELEVANCE: NCCL distribution increased with age, and erosive risk factors caused by change in dietary habits might affect the incidence of NCCLs for elders. TRIAL REGISTRATION: UMIN000041982.

Saliva secretion is reduced in proton pump inhibitor-responsive non-erosive reflux disease patients.

BACKGROUND: There is no consensus on the relationship between saliva secretion and non-erosive reflux disease (NERD). In this study, saliva secretion and salivary epidermal growth factor (EGF) in patients with NERD were examined. METHODS: Thirty-one PPI-responsive NERD patients and 31 control subjects were recruited for this case-control study. Saliva secretion testing was performed. Saliva secretion was assessed as follows: each patient chewed sugar-free gum for 3 min prior to endoscopy, and the amount and pH of saliva before and after acid loading as an index of the acid-buffering capacity were measured. The salivary EGF concentration was assessed by ELISA. RESULTS: The amount of saliva secreted was significantly lower in the NERD group than in the control group, with medians (25th-75th percentile) of 4.0 mL/3 min (2.0-6.0) and 6.0 (3.9-8.0), respectively (p = 0.0131). Salivary pH was significantly lower in the NERD group (7.0 [6.8-7.2]) than in the control group (7.2 [7.0-7.3], p = 0.0100). Salivary pH after acid loading was significantly lower in the NERD group (5.8 [5.4-6.2]) than in the control group (6.3 [6.1-6.5], p = 0.0002). The difference in pH of stimulated saliva after acid loading (1.2 [0.9-1.5], p = 0.0021) was significantly higher in the NERD group than in the control group (0.8 [0.7-1.1]). The salivary EGF concentration was significantly higher in the NERD group (2513.0 pg/mL [1497.5-5005.0] than in the PPI-responsive group (1641.0 [1139.8-2092.0], p = 0.0032). CONCLUSION: Stimulated saliva secretion was reduced in PPI-responsive NERD patients.

Stimulated saliva secretion is reduced in proton pump inhibitor-resistant severe reflux esophagitis patients.

BACKGROUND: Salivary secretion in patients with proton-pump inhibitor (PPI)-resistant severe reflux esophagitis has not been examined. In this study, saliva secretion and salivary epidermal growth factor (EGF) in patients with PPI-resistant severe reflux esophagitis were investigated. METHODS: We recruited 22 PPI-resistant and 22 PPI-responsive severe reflux esophagitis patients who were not infected with Helicobacter pylori. Saliva secretion testing and esophageal manometry using high-resolution manometry were performed. Saliva secretion was assessed as follows: each patient chewed sugar-free gum for 3 min prior to endoscopy and the amount and pH of saliva as well as the pH of saliva after acid loading as an index of the acid-buffering capacity were measured. The salivary EGF concentration was assessed by ELISA. RESULTS: The amount of saliva secreted was significantly lower in the PPI-resistant group than in the PPI-responsive group, with medians (25th-75th percentile) of 3.7 (2.2-6.8) and 4.9 (4.0-7.8) mL, respectively (p = 0.029). Salivary pH was significantly lower in the PPI-resistant group [6.9 (6.7-7.2)] than in the PPI-responsive group [7.2 (7.1-7.4), p = 0.001]. Salivary pH after acid loading was significantly lower in the PPI-resistant group [5.6 (5.3-5.9)] than in the PPI-responsive group [6.4 (6.1-6.5), p = 0.002]. The salivary EGF concentration was significantly higher in the PPI-resistant group [3211.5 (1865.0-4121.5)] than in the PPI-responsive group [1816.0 (1123.5-2792.3), p = 0.041]. No significant differences were observed in the proportion of esophageal motility abnormalities. CONCLUSION: Stimulated saliva secretion was reduced in PPI-resistant severe reflux esophagitis patients.

Evidence-based consensus for treating incipient enamel caries in adults by non-invasive methods: recommendations by GRADE guideline.

Remineralization treatment, which offers the advantage of being non-invasive, is increasingly being used as a minimal intervention treatment in managing incipient enamel caries. The aim of this review was to develop EBM guideline for optimized strategies for non-invasive treatment of incipient enamel caries. Japanese Society of Conservative Dentistry (JSCD) guideline committee formulated a Guideline for treating incipient enamel caries using the GRADE system, which is the global, mainstream standard for guideline development. The committee selected the most frequent clinical questions (CQs) in treating incipient enamel caries and identified clinically important outcomes in evaluating the efficacy of treatments. Using extensive electronic and manual searches, relevant randomized controlled trials and controlled clinical trials were identified. Based on evidence profiles produced by the committee, the panel discussed the effects, benefits and disadvantages of the selected treatments, as well as their cost effectiveness and feasibility, in order to achieve a consensus in treating incipient enamel caries non-invasively. A recommendation was made for each clinical question after voting by the panel members. Based on the evidence profile and panel discussions for each CQ, the experts strongly recommended application of topical fluoride to inhibit cavitation of incipient enamel caries, and to diminish white spot lesions.

Remineralization capacity of carious and non-carious white spot lesions: clinical evaluation using ICDAS and SS-OCT.

OBJECTIVES: To assess the remineralization capacity of carious, non-carious, and combined white spot lesions (WSLs) using the ICDAS and SS-OCT. MATERIALS AND METHODS: This clinical trial was based on a quasi-experimental design. Forty-two healthy subjects (median age 26.6 years), who visited university hospital and had at least one WSL with an ICDAS score of 2 or 1, were recruited. The subjects chewed a non-blind sugar-free gum containing bioavailable calcium and fluoride for 3 months. The remineralization capacities of carious and non-carious 121 WSLs were assessed using ICDAS by two calibrated non-blind examiners and optical boundary depth (BD) by SS-OCT at a monthly recall. The outcome variables, transitions of ICDAS score, mean BD, and mean BD recovery rate (RR%), were statistically analyzed using the chi-square test, two way-repeated measures ANOVA, and Wilcoxon rank sum test, respectively (alpha = 0.05). RESULTS: Based on the visual inspection, OCT images at the baseline, 72 WSLs were purely carious, 20 were non-carious (developmental) lesions, while 29 were combined (carious-developmental). The responses of WSLs over time showed to be highly variable. There was a significant difference in transitions of ICDAS scores after 3 months between carious and non-carious WSLs (p < 0.05) and non-carious and combined WSLs (p < 0.05). Carious and combined WSLs underwent significant changes in the mean BD between baseline (161.8 ± 56.8 µm) and 2 months (130.7 ± 57.4 µm) or 3 months (119.1 ± 57.5 µm) (p < 0.05), while there was no significant difference between baseline (132.2 ± 26.2 µm) and 2 months (122.8 ± 24.1 µm) or 3 months (119.8 ± 22.6 µm) in non-carious WSLs (p > 0.05). There was a significant difference in mean RR% after 2 and 3 months between carious and non-carious WSLs (p < 0.05). CONCLUSIONS: The remineralization capacity of WSL was variable among the cases and subjects, and depended on the WSLs history, etiology (carious, non-carious, or combined lesion) and structure (histological pattern). CLINICAL RELEVANCE: Carious WSLs showed the highest remineralization potential.

pH Mapping on Tooth Surfaces for Quantitative Caries Diagnosis Using Micro Ir/IrOx pH Sensor.

A quantitative diagnostic method for dental caries would improve oral health, which directly affects the quality of life. Here we describe the preparation and application of Ir/IrOx pH sensors, which are used to measure the surface pH of dental caries. The pH level is used as an indicator to distinguish between active and arrested caries. After a dentist visually inspected and defined 18 extracted dentinal caries at various positions as active or arrested caries, the surface pH values of sound and caries areas were directly measured with an Ir/IrOx pH sensor with a diameter of 300 µm as a dental explorer. The average pH values of the sound root, the arrested caries, and active caries were 6.85, 6.07, and 5.30, respectively. The pH obtained with an Ir/IrOx sensor was highly correlated with the inspection results by the dentist, indicating that the types of caries were successfully categorized. This caries testing technique using a micro Ir/IrOx pH sensor provides an accurate quantitative caries evaluation and has potential in clinical diagnosis.

Effect of a calcium phosphate and fluoride paste on prevention of enamel demineralization.

This study aimed to examine the anti-demineralization capacities of (a) tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) and 950 ppm fluoride paste, (b) casein phosphopeptide amorphous calcium phosphate paste and (c) 950 ppm fluoride solution using optical coherence tomography (OCT). Enamel blocks were cut from the bovine incisors and treated using one of the above-mentioned three materials or deionized water as control (n=10). All samples were subjected to a demineralization gel for 1 h followed by a remineralization solution for 23 h. This experimental cycle was repeated for 28 days. The specimens were imaged using OCT at baseline and at four stages and measured lesion depth using image analysis software (ImageJ). Repeated measures ANOVA revealed that demineralization time, material and their interaction significantly affected the optical lesion depth (p<0.001). TTCP and DCPA and 950 ppm fluoride paste and 950 ppm fluoride solution showed significantly lower lesion progress compare to other groups (p<0.05).

Erosive Tooth Wear Among Different Tooth Types and Surfaces in Japanese Adults 15 to 89 Years Old.

PURPOSE: To evaluate the prevalence of erosive tooth wear on buccal, incisal/occlusal and palatal/lingual surfaces in a wide age range of Japanese adults. MATERIALS AND METHODS: The study included a total of 1108 adults aged 15 to 89 years in Tokyo, Japan. The subjects were asked to complete a self-administered nutrition-related questionnaire. Two examiners evaluated tooth wear on the buccal, occlusal/incisal and palatal/lingual surfaces in a full-mouth recording, using a modified Smith and Knight tooth-wear index. Subjects who frequently consumed acidic beverages or food, or had gastric reflux and at least one tooth with an initial enamel smooth-surface wear facet were placed in an erosion-positive group, and the rest of subjects were placed in the erosion-negative group. RESULTS: 26.1% of the participants were placed in the erosion-positive group. For buccal surfaces, advanced wear progression was predominantly observed on maxillary and mandibular anterior teeth, especially in the youngest age group (15-39 years). On incisal/occlusal surfaces, early dentin exposure was observed in the middle age group (40-49 years) in the erosion-positive group. For palatal/lingual surfaces, wear progression was mainly observed on maxillary anterior teeth among 30- to 39-year olds and 50- to 59-year-old in the erosion-positive group, but that prevalence was lower than for the other tooth surfaces. CONCLUSIONS: For all age groups of Japanese adults, the prevalence of erosive tooth wear depended on tooth types and surfaces.

Multifactorial logistic regression analysis of factors associated with the incidence of erosive tooth wear among adults at different ages in Tokyo.

OBJECTIVES: The aim of this study was to evaluate factors associated with the incidence of erosive tooth wear (ETW) among adults at different ages in Tokyo using multifactorial logistic regression analysis. MATERIALS AND METHODS: The study sample consisted of a total of 1108 subjects aged 15 to 89 years in Tokyo, Japan. Two examiners evaluated ETW in a full-mouth recording. The subjects were asked to complete a self-administered daily diet, habit, and health condition questionnaire. Subjects who had frequent acid consumption or gastric reflux and at least one tooth with initial enamel wear were placed in the ETW-positive group, and the remainder of the subjects was placed in the ETW-negative group. Logistic regression analyses were carried out to identify factors collectively associated with ETW. RESULTS: Logistic regression analysis showed that greater frequencies of carbonated or sports drink consumption were associated with higher incidence of ETW for all age groups except for 70-89 years. Adults in the 30-39-year group who reported suffering from heartburn were about 22.3 times more likely to develop ETW, while 40-49-year adults who had repeated vomiting were about 33.5 times more likely to exhibit ETW compared with those who did not experience vomiting. CONCLUSION: Age-specific dietary habits were clearly observed among adults at different ages in Tokyo, and there were significant differences in intrinsic and extrinsic factors between ETW-positive and ETW-negative groups for each age group. CLINICAL RELEVANCE: Both greater frequency of carbonated and sports drink consumption were associated with higher incidence of ETW among adults at different ages in Tokyo.

A comparative study of the susceptibility of cut and uncut enamel to erosive demineralization.

This study aimed to evaluate the susceptibility of cut and uncut enamel surfaces to an erosive challenge and to examine the resultant characteristics/morphological changes. Ten extracted human incisors were used for preparation of enamel samples, and samples were immersed in citric acid. After 3 (total 3 min) and 6 cycles (total 6 min) of erosive challenges, surface loss (SL) and morphological changes were measured using scanning microscopy and FIB-TEM. Ca release (CA) and surface hardness (SH) were measured using a calcium-sensitive electrode and hardness tester respectively. Mean values of all measurements were statistically analyzed by using a t-test. Uncut enamel samples had significantly lower SL and greater SH than cut enamel (p<0.01). Cut enamel samples after 3 cycles showed higher CA compared with those from uncut enamel samples (p<0.05). Cut enamel was shown to be more susceptible to acidic dissolution and deeper acid penetration than uncut enamel after erosive demineralization.

White spot lesion remineralization by sugar-free chewing gum containing bio-available calcium and fluoride: A double-blind randomized controlled trial.

OBJECTIVES: To assess the effect of chewing gum containing phosphoryl oligosaccharides of calcium (POs-Ca) and fluoride on white spot lesion (WSL) remineralization in comparison with POs-Ca or placebo (control) chewing gums, in double- blind, randomized, controlled trial. METHODS: Thirty-seven healthy subjects, who had at least one WSL, with an ICDAS score of 2 or 1, were recruited for this study. The subjects were randomly divided into three groups (control, POs-Ca, POs-Ca+F) and chewed two slabs of each gum three times every day for 3 months. WSLs were assessed using ICDAS criteria and optical boundary depth (BD) by optical coherence tomography (OCT) system at a monthly recall. Data were analyzed by Wilcoxon rank-sum test and Wilcoxon signed rank test with Bonferroni corrections at 0.05 significance level. RESULTS: Visual score changes from ICDAS score 2 to score 1 over the course of the study were observed; control (30%), POs-Ca (48%) and POs-Ca+F (45%). Unlike the control gum, chewing POs-Ca and POs-Ca+F gums resulted in significant changes in the mean value of BD over the 3 months course of the study (p<0.05). There was a significant difference in mean value of BD after first month between POs-Ca+F and control groups (p<0.05). CONCLUSIONS: This study highlighted the importance of calcium and fluoride ion bioavailability in the reinforcement of demineralized enamel lesions by chewing gums. Furthermore, adding fluoride to POs-Ca might speed up the remineralization progress on natural WSL.