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A water fluoridation program launched in the United States in 1945 has become a worldwide application for caries prevention. Although such a program is important in Japan, water fluoridation in large communities has not been established. This study aimed to develop safe small-scale water fluoride equipment that can be easily used to carry out water fluoridation programs in areas with children in long-term care facilities, and in developing countries without water supply facilities.Batch-type NaF addition adjustment equipment was manufactured as small-scale water fluoride equipment. The fluoride concentration of the adjusted water with this equipment was measured using an ion meter and a fluoride composite electrode. All 51 water quality standards set by the Ministry of Health, Labour, and Welfare of Japan were tested.The fluoride ion concentration of the adjusted water was 0.7 mg/L and it was constant and stable. The adjusted water conformed to the water quality standard values of the Japanese Water Supply Law.Water produced with small-scale water fluoridation equipment had a fluoride concentration of 0.7 mg/L, which is the recommended concentration for caries prevention. The fluoride concentration was stable.

Background: Oral potentially malignant disorders, which include oral lichen planus (OLP), are clinical presentations that carry a risk of development to cancer in the oral cavity. Oral lichenoid lesions (OLLs) are also termed interface/lichenoid mucositis. Malignant transformation of them remains controversial, but distinct clinical and histological criteria for how to differentiate OLP from OLLs have not been developed. Objectives: The purpose of this study was to elucidate findings that can allow histopathological differentiation of OLP and OLLs using histomorphological and immunohistochemical analyses. Materials and Methods: Analyses were performed in 10 cases diagnosed with OLP and 9 cases diagnosed with OLLs. Cytokeratin 19 (CK19), Ki-67 and CD3 were used as primary antibodies to detect basal cells, proliferative activity and T-cell distribution, respectively, and Perlecan and COX-2 to evaluate epithelial intracellular arrangements and interstitial distributions of proteoglycans and enzymes. Results: For CK19, positive cells were significantly found in OLLs at both the prominent area and site adjacent to the lesion comparison with those of OLP’s. The number of COX-2 positive cells was significantly higher in spinous and basal layers in OLLs of the prominent area. Additionally, OLLs showed mild to moderate expression for perlecan in the basal to spinous layers and in subepithelial tissue. Conclusion: Almost no basal cells were noted in the prominent area in OLP. COX-2 and perlecan were found in the basal to spinous layers in OLLs. Although there are restrictions, these suggested the possibility of helping to distinguish between OLP and OLLs.

Background: Liquid-based cytology (LBC) is a method of manufacturing cyto-diagnostic specimens. Improved accuracy is expected from standardizing specimen production and use of this method is rapidly spreading in oral cytology. On the other hand, LBC reportedly requires training to show peculiar cell findings compared to those of conventional smear cytology (CVC). Few studies have compared detailed cell findings for oral CVC and LBC. Objectives: The aim of this study was to compare cytological findings between CVC and LBC using cytomorphological image analysis. Materials and Methods: Cytological specimens were collected from 20 patients (negative for squamous neoplasia in 10, dysplasia in 5, squamous cell carcinoma in 5) and 5 controls of the tongue between January 2017 and December 2018. Two different preparation techniques were investigated cytomorphologically for CVC and LBC (BD CytorichTM). Results: LBC showed significantly higher cell numbers than CVC for all lesions. LBC-to-CVC ratio ranged from 9.52 (hyperkeratosis) to 1.87 (deep cells in oral squamous cell carcinoma (OSCC)). Nuclear area of normal, hyperkeratosis, and inflammation were significantly higher in LBC than those of CVC. Hyperchromasia was significantly more frequent with CVC than with LBC for hyperkeratosis, inflammation, dysplasia and OSCC. There was no significant difference in circularity between CVC and LBC among all lesions. Conclusion: Only one cytomorphological disadvantage was seen with LBC, in the form of decreased hyperchromasia. Further clarification of the advantages and disadvantages of LBC is needed, including management of precision and screening practices.

Quality of life (QOL) and mortality are true endpoints of epidemiological or medical research, especially for community-dwelling older adults. Nutritional status and activities of daily living (ADLs) are associated with QOL and mortality. Good oral health status supports a good nutritional status. The aim of this study was to elucidate the complex structure of these important health-related factors. We surveyed 354 healthy older adults at the age of 85. Nutritional status was evaluated by the serum level of albumin. QOL, ADLs, self-assessed chewing ability, serum albumin level, and mortality during the 15 year follow up period were analyzed. Self-assessed chewing ability was associated with QOL and ADLs. Self-assessed chewing ability for slight-hard foods was associated with mortality in men. However, it was not associated with the serum albumin level. The serum albumin level was associated with mortality in women. These results indicate that maintaining good oral function is not enough. Nutritional instruction in accordance with oral function is indispensable for health promotion in older adults. When planning health promotion strategies for older adults, different strategies are needed for men and women.

Background: Gingival recession and concomitant alveolar bone resorption are hallmarks of periodontal diseases and excessive fluoride intake has some deleterious effects on teeth, bone and soft tissues. Autophagy is a highly conserved intracellular digestion process that degrades damaged proteins and organelles but the biological roles of autophagy in pathological aspects of oral tissues remain largely unknown. We sought to elucidate the function of autophagy, especially its interplay with apoptosis and oxidative stress, in the oral toxicity induced by exposure to 5 mM sodium fluoride (NaF). Methods: HCEM2 cementoblast cells in culture were exposed to 5 mM NaF for 5 min, after which cell viability and cell apoptosis were assessed using the MTS assay and an Annexin V-FITC/PI apoptosis detection kit, respectively. Real-time quantitative RT-PCR and Western blotting were performed to characterize the mRNA and protein expression levels of markers for autophagy, apoptosis, and oxidative stress. C57BL/6 mice were exposed to 5 mM NaF in their drinking water from 12 to 58 weeks. Micro-computed tomography was used to measure changes in their alveolar bone while immunohistochemistry and immunofluorescence staining was used to evaluate protein expression levels of autophagy, apoptosis, and oxidative stress markers.Results: Cementoblasts exposed to 5 mM NaF had decreased levels of autophagy, as shown by reduced expression levels of ATG5, Beclin1 and LC3-II, elicited excessive apoptosis, which in turn induced oxidative stress and inflammation, as manifested by elevated levels of Bax, cleaved caspase-3, SOD1 and phospho NF-κB. Consistently, the in vivo results verified the findings of the in vitro study and treatment of mice with 5 mM NaF resulted in histological abnormalities in periodontal tissues, induced excessive oxidative stress and apoptosis, and reduced autophagy. These results correlated with the immunofluorescence observations, thus confirming the pivotal role of autophagic flux dysfunction in 5 mM NaF-induced cell death. Micro-computed tomography analysis demonstrated that 5 mM NaF caused a decrease in bone areas of mice compared with controls. Exposure to 5 mM NaF induced RANKL (receptor activator of nuclear factor κB ligand) and cathepsin K expression in periodontal tissues, while ATG5 and Beclin1 expression was abrogated by 5 mM NaF.Conclusion: Taken together, our findings suggest that 5 mM NaF elicits oral toxicity that contributes to excessive apoptosis, oxidative stress, and defective autophagy, which aggravates periodontal tissue damage.

The oral microbiome of healthy older adults has valuable information about a healthy microbiome. In this study, we collected and analyzed the oral microbiome of denture plaque and tongue coating samples from four female centenarians. After DNA extraction and purification, pyrosequencing of the V3&ndash, V4 hypervariable regions of the 16S rRNA was carried out. The bacterial taxonomy for each lead was assigned based on a search of the EzBioCloud 16S database. We obtained a total of 199,723 valid, quality-controlled reads for denture plaque and 210,750 reads for tongue coating. The reads were assigned 407 operational taxonomic units with a 97% identity cutoff. Twenty-nine species were detected in both denture plaque and tongue coatings from all subjects. Firmicutes was the most abundant phylum, the Streptococcus salivarius group was the most abundant species in both the denture plaque and tongue coatings, and the Fusobacterium nucleatum group was detected in all subjects. In the bacterial profile, species formed clusters composed of bacteria with a wide range of prevalence and abundance, not dependent on phyla, each cluster may have specific species that could be candidates for a core microbiome. Firmicutes and Veillonella were abundant phyla on both plaque and tongue coatings of centenarians.

Background: A new microorganism identification method using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) has been developed, however, reports on its use for delineating Candida spp. are scarce. Objectives: The purpose of this study was to compare the identification accuracy of mixed infection between culture test and MALDI-TOF MS. Materials and Methods: Eighty-nine denture wearers (average 74.0 ± 9 years) were selected. Specimens were immediately inoculated onto selective medium for CHROMagarTM Candida, and were also carried out using MALDI-TOF MS. The distribution frequencies of them were analyzed. Results: The numbers and rates of detection/non-detection by MALDI-TOF MS of genus Candida were 58/31 (65.2%/34.8%), respectively. Infection types were single infection in 34 (38.2%), mixed infection in 24 (27.0%), and non-infection in 31 (34.8%) cases. Concerning the single infection, C. albicans was the most predominant (58.8%), followed by C. parapsilosis (17.6%), C. glabrata (14.7%), C. tropicalis (5.9%), and C. krusei (2.9%). As for the mixed infection, the most frequent combination was C. albicans and C. glabrata (50.0%), followed by C. albicans and C. parapsilosis (29.2%), C. albicans and C. tropicalis (8.3%), C. glabrata and C. tropicalis (4.2%), C. albicans, C. glabrata, and C. parapsilosis (4.2%), and C. albicans, C. parapsilosis, and C. glabrata (4.2%). There were four MALDI-TOF MS positive results that were negative by the culture test. Conversely, there were six MALDI-TOF MS negative results that were positive by the culture test. The sensitivity and specificity of MALDI-TOF MS were 0.929 and 0.840, respectively. The concordance rate of genus Candida was 0.644, indicating substantial agreement. Conclusion: Candida infection is complicated by disease type and oral cavity environment changes due to aging. A rapid microorganism detection method, such as MALDI-TOF MS, will be helpful to quickly determine the causative pathogen in dental infections.

Oral squamous cell carcinoma (OSCC) often causes lymphatic metastasis, particularly to the regional cervical lymph nodes. Although lymphatic metastasis is closely associated with lymphangiogenesis in the tumor tissues, the detailed mechanisms are not yet fully understood. The purpose of this study was to examine the morphological association of lymphangiogenesis in the tumor stromal tissue with cervical lymph node metastases in OSCC. The medical records of 13 patients treated for OSCC affecting the tongue at the Department of Oral Surgery of Nihon University School of Dentistry at Matsudo Hospital between November 2003 and March 2011 were reviewed. The 13 cases were divided into two groups, with 7 cases in the metastasis group and 6 cases in the non-metastasis group. Histopathological (hematoxylin-eosin stain) and immunohistochemical (D2-40 antibody) examinations were performed. Lymphatic vascular density and lymphatic vascular area, lymphatic vascular morphology, and the number of lymph vessels were quantified using ImageJ software. The lymphatic vessels in the metastasis group were distributed with higher density and ran irregularly, with more remarkable deformation than those in the non-metastasis group. Cervical lymph node metastasis is one of the factors affecting progression and the prognosis of OSCC patients. In the present study, lymphatic vessels were found in the OSCC stroma, which also suggests that an increased density of lymphatic vessels leads to cervical lymph node metastases.

Tumor growth is closely related to the development of an intrinsic vascular network. However, microvascular appearance was not regarding highly to pathological diagnosis, though clinical applicability of endoscopic narrow-bad imaging (NBI) is developed in the oral cavity. To analyze changes of intraepithelial papillary capillary loop (IPCLs) patterns as the utility for pathological diagnosis, comparative histomorphometric analysis of IPCLs among squamous cell hyperplasia, leukoplakia with low- or high-grade dysplasia, and oral squamous cell carcinoma (OSCC) had performed. Subjects were 40 clinically hyperkeratosis, histologically consisted 5 groups; each 10 of squamous cell hyperplasia, low- or high-grade dysplasia, OSCC and normal mucosae. Sections with smooth muscle actin and CD34 immunoreactivities were used to examine comparative histomorphometric analysis on the basis of IPCL irregularities. The area, shortest diameter, proximity to the basement membrane and circularity were measured using Win Roof image analysis software. Statistical analyses were done by Kruskal–Wallis and Steel–Dwass tests. Values of p

Introduction The South Pacific Medical Team (SPMT) has supported oral health care for Tongan juveniles since 1998. This voluntary activity, named the MaliMali ('smile' in Tongan) Programme, is evaluated in detail in this paper. Methods This evaluation was guided by the Reach, Effectiveness, Adoption, Implementation, Maintenance (RE-AIM) framework. The objectives were to explore: (i) whether the programme was accessible to Tongan schoolchildren (Reach); (ii) the impact of the programme on decayed, missing and filled teeth (DMFT) scores and toothbrushing habits (Effectiveness); (iii) factors that affected the adoption of the programme (Adoption); (iv) whether implementation was consistent with the programme model (Implementation); and (v) the long-term sustainability of the programme (Maintenance). Results The MaliMali Programme has grown into an international project, has spread countrywide as a uniform health promotion and is reaching children in need. Following implementation of this programme, the oral health of Tongan juveniles has improved, with a decrease in the mean DMFT index and an increase in toothbrushing. To provide training that will allow Tongans to assume responsibility for the MaliMali Programme in the future, dental health education literature was prepared and workshops on oral hygiene and the MaliMali Programme were held frequently. At present, the programme is predominantly managed by Tongan staff, rather than by Japanese staff. Conclusions This evaluation found the MaliMali Programme to be feasible and acceptable to children and schools in the Kingdom of Tonga. The programme promotes oral health and provides accessible and improved oral health care in the school setting, consistent with the oral health-promoting school framework.

Background/aims Lacerations of the oral mucosa and fractures of alveolar processes commonly occur in traumatic dental injuries (TDIs). Impaired wound healing and tissue regeneration have severe consequences on the quality of life. Bone marrow mesenchymal stem cells (BMMSCs) possess the ability of self-renewal and multipotential differentiation. Treatment with low-level sodium fluoride (NaF) has emerged as a promising approach to enhance wound repair. The aim of this study was to assess the effects of low-level NaF on soft tissue healing and on the proliferation, migration and extracellular matrix synthesis of BMMSCs. Material and methods BMMSCs derived from mice were treated with 50 μM, 500 μM, or 5 mM NaF for 12, 24, and 48 hours, and cell proliferation was assessed by the MTS assay. Cell motility was detected at 12 and 24 hours by a wound healing assay, and osteoblastic differentiation for 21 days by 1% Alizarin Red S staining in 50 μM NaF-treated BMMSCs. Gene expression of Runx2 and Osteocalcin was evaluated by quantitative real-time PCR. An experimental rat skin wound model was employed, and levels of c-Myc, Ki67, fibronectin, and vimentin were assessed by immunohistochemistry. Results There was a significant induction in the proliferation and migration of BMMSCs treated with 50 μM NaF. The expression of Ki67 and c-Myc protein was increased in tissues treated with 50 μM NaF, and the expression of fibronectin and vimentin in the 50 μM NaF-treated tissues was stimulated. Alizarin Red staining revealed enhanced mineralization in 50 μM NaF-treated BMMSCs with increased expression of Runx2 and Osteocalcin, indicating their upregulated osteogenic differentiation. Conclusion Low-level NaF could promote soft tissue healing and hard tissue regeneration.

Osteoclasts are bone-specific multinucleated cells generated by the differentiation of monocyte/macrophage lineage precursors. Regulation of osteoclast differentiation is considered an effective therapeutic approach to the treatment of bone-lytic diseases. Periodontitis is an inflammatory disease characterized by extensive bone resorption. In this study, we investigated the effects of sodium fluoride (NaF) on osteoclastogenesis induced by Porphyromonas gingivalis, an important colonizer of the oral cavity that has been implicated in periodontitis. NaF strongly inhibited the P. gingivalis-induced alveolar bone loss. That effect was accompanied by decreased levels of cathepsin K, interleukin (IL)-1β, matrix metalloproteinase 9 (MMP9), and tartrate-resistant acid phosphatase, which were up-regulated during P. gingivalis-induced osteoclastogenesis. Consistent with the in vivo anti-osteoclastogenic effect, NaF inhibited osteoclast formation caused by the differentiation factor RANKL (receptor activator of nuclear factor κB ligand) and macrophage colony-stimulating factor (M-CSF). The RANKL-stimulated induction of the transcription factor nuclear factor of activated T cells (NFAT) c1 was also abrogated by NaF. Taken together, our data demonstrate that NaF inhibits RANKL-induced osteoclastogenesis by reducing the induction of NFATc1, ultimately leading to the suppressed expression of cathepsin K and MMP9. The in vivo effect of NaF on the inhibition of P. gingivalis-induced osteoclastogenesis strengthens the potential usefulness of NaF for treating periodontal diseases.

Background: The aim of this study was to evaluate the association between dental caries and concomitant infections of Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus) according to the ratio of cariogenic bacteria in plaque samples from adults to obtain basic data to develop clinical and chairside culture assay (kits) for assessment of dental caries risk. Methods and Materials: Plaque samples from 192 adult volunteers (age range, 20-28 years) were obtained using sterile toothbrushes. Caries history and the number of decayed, missing, and filled (DMF) teeth were determined. Subjects were divided into high- and low-risk groups according to the ratio of S. mutans to total streptococci (Sm/TS ratio) and the number of S. mutans. Results: The numbers of S. mutans and S. sobrinus and the Sm/TS ratio were significantly greater in the cariesactive (CA) group than in the caries-free (CF) group. The number of bacteria and the Sm/TS ratio for the high-risk S. mutans plus detectable S. sobrinus subgroup was significantly greater in the CA group than in the CF group. High levels of S. mutans and S. sobrinus were significantly associated with dental caries. A significantly high caries risk was found between DMF teeth and the Sm/TS ratio for S. mutans when S. sobrinus was detected. Conclusions: The number of dental caries was greater in adults with plaque samples concomitantly infected with high levels of S. mutans and S. sobrinus than in those with a single infection. These findings indicate the usefulness of analysis of cariogenic dental bacteria to detect adult populations with the severity of dental caries according to the Sm/TS ratio using dental plaque samples.

Background: Public oral health surveys have shown that the prevalence of dental caries in adults is increasing worldwide, resulting in increased workload and costs of dental and other clinical oral health services. Total streptococci are broadly grouped into mutans streptococci and three other species. They constitute a majority of bacteria found in the mouth. Of the total streptococci, the group of bacteria that primarily causes dental caries is mutans streptococci, which consists of seven species. Streptococcus mutans (S. mutans) is the mutans streptococcus most strongly associated with dental caries. To date, no simple assay (kit) has been developed for detecting S. mutans using plaque samples for caries risk assessment. This study aimed to evaluate the association between S. mutans and dental caries in adults based on the number and proportion of cariogenic bacteria in toothbrush plaque samples by culture methods to obtain basic data to develop clinical and chairside culture assay for caries risk assessment. Materials and Methods: Plaque samples from 164 adult volunteers were obtained using sterile toothbrushes. The ratio of S. mutans to total streptococci (Sm/TS ratio) was determined by counting the number of colonies by culture methods. The extent of dental caries and the relative risk based on bacterial counts were assessed. Results: The differences between Sm/TS ratios (%) in caries-free, medium-caries, and caries-active groups were statistically significant (p

Objective In this study, we investigated the role of phenytoin (PHT) in death receptor-induced apoptosis of gingival fibroblasts to clarify the mechanism of PHT-induced gingival overgrowth. Methods Human gingival fibroblasts were cultured to semiconfluence and treated with PHT (0.025, 0.1, 0.25, and 1.0 μM) for 48 h, and then, the apoptotic cell numbers were relatively determined by absorptiometry. After 24 h of 0.25 μM PHT treatment, caspase activity was measured by absorptiometry, apoptotic and cell cycle phase distribution was analyzed by flow cytometry, expression levels of apoptotic genes were quantified by real-time qPCR, and expression of apoptotic proteins was detected by Western blot analysis. After 48 h of 0.25 μM PHT treatment, appearance of apoptotic cells was detected by TUNEL assay. Results PHT treatment decreased the proportion of apoptotic cells in gingival fibroblasts compared to a serum-free control culture in response to the protein changes as follows: PHT upregulated c-FLIP and, in turn, downregulated FADD, caspase-8, and caspase-3; PHT upregulated c-IAP2 and downregulated TRAF2; PHT downregulated caspase-9 and caspase-3 via decreased RIPK1 activity and increased Bcl-2 activity. Conclusion PHT-induced gingival overgrowth may result from the above-mentioned mechanisms involving apoptosis inhibition in gingival fibroblasts.

Candidiasis of the oral mucosa arises chiefly as a re- sult of infection with Candida albicans. Many clinico- pathological analyses of macroscopic findings have been described, although the clinical findings of oral candidiasis vary considerably and the conditions are complex. The present study analyzes the distribution, clinical, cytological and histological diagnoses of oral candidiasis, associated complex diseases and the di-agnostic value of cytology. The ratio of Candida in-fection was 28.9% among 1551 study participants. Females were infected significantly more often than men (p < 0.01) and the affected age range was 60 - 79 years (61.0%, p < 0.01). The predominantly affected areas were the tongue (48.3%, p < 0.01) and gingiva (20.0%, p < 0.01), and occurrence at multiple loci was seen in 43 (9.6%) patients. The typical clinical find- ings of oral candidiasis were ulcerative/erythematous lesions (33.2%, p < 0.01) and pseudomembranous candidiasis (31.6%, p < 0.01). A histopathological dia- gnosis of candidiasis based on biopsy specimens from 26 lesions in patients with Candida infection indicated by cytology was confirmed from cultures. The break- down of a cytological to a definite diagnosis was 6 positive (SCC 4, verrucous carcinoma 1, moderate to severe dysplasia 1), 6 suspected positive (mild dyspla- sia, 2; moderate to severe dysplasia, 2; papilloma, 1 and SCC, 1) and 14 negative (epulis, 3; papilloma, 3; granulation tissue, 2; fibrosis, 2 and others, 4). Exfo-liative cytology can easily judge the presence of Can-dida species, although experience is necessary for the presumptive diagnosis of an oral mucosal disease. The application of exfoliative cytology using the Pe- riodic acid-Schiff reaction is helpful for the earlier detection of oral candidiasis with various macrosco- pic findings.

There have been many studies on the relationships among various methods for determining whole salivary volume and these methods' effectiveness. The methods of determining this volume include those that determine the salivary volume of a subject at rest and during salivary stimulation. The convention method uses both the spitting method at rest and the paraffin mastication method. In the present study, we compared the reproducibility of the salivary volumes determined by the modified ion dilution method (the modified fluoride dilution method) and conventional methods. Salivary volumes in decreasing order were sour stimulation with the modified fluoride dilution (MFD) method, during mastication, under tasteless stimulation with the MFD method, and at rest. Higher correlations were found between the salivary volumes at rest and during mastication determined by the conventional method (r=0.57, p

In the current study, we used the modified ion dilution method to evaluate the influence of the circadian rhythm on the salivary volume in response to varying sour concentrations. We found that the salivary volume changed depending on when the sample was taken and on the sour concentration. Specifically, there was a definite trend for the salivary volume to be low in the morning and to increase from around lunchtime to evening. In addition, the influence of the circadian rhythm on salivary volume tended to be reduced by a strong taste stimulation (high sour concentration). These results suggest that the greater the amount of stimulation (sour stimulation), the smaller the effect of circadian rhythm on the salivary volume.

Since 1998, the authors have been working to improve the oral health of children at kindergartens and primary schools in the Kingdom of Tonga (Tonga). Our primary activity has been a school-based fluoride mouth-rinsing (FMR) program. FMR is performed using 7-10 mL of a 0.2% NaF solution for 1 min once per week at each school. In the present study, we evaluated the effect of school-based FMR on dental caries incidence among Tongan schoolchildren. A total of 109 children aged 10 years were evaluated at six primary schools on Tongatapu Island. The FMR group comprised 46 children who had participated in the school-based FMR program for at least 5 years 6 months; the control group comprised 63 children who had participated in the school-based FMR program for 1 year or less. During standardized dental examinations, decayed, missing, and filled teeth were counted by a single dentist at each school. The school-based FMR program effectively decreased the number of dental caries. A school-based FMR program may thus be very beneficial in preventing caries among children in Tonga.

Since 1972, community water fluorida- tion programs have not been practiced in Japan. Risk perception among the population plays an important role in the implementation of water fluoridation programs. The oral health behavior of Japanese chil- dren has changed, especially due to recent increases among children in the use of fluoridated products and fluoride applications by dentists. The purpose of this study was to examine the associations between oral health behavior, risk perception, and the desire to implement water fluoridation among Japanese residents. We distributed a questionnaire survey (response rate: 92.8%) to mothers with children aged two or three years (n = 573). There was a correlation between anxiety and level of motivation to implement water fluoridation (Spearman coefficient: 0.355, P < 0.001). Exposure to various fluoride experiences was higher in the "not anxious" group. The motivation level was significantly higher in subjects who had a better understanding of the effectiveness of fluoride, those who used fluoride tooth paste, and those whose children received fluoride applications from dentists. We conclude that increased knowledge of and experi- ence with fluoride might help decrease the perception of risk and increase motivation for implementing water fluoridation among the general public. (J Oral Sci 53, 313-319, 2011)