Dental Benefits Research Articles

Effects of Adult Medicaid Dental Benefits Elimination on Child Dental Care Use.

The objective of this study was to examine the effect of adult dental benefit cuts on child dental use in Washington state Medicaid and determine if cuts affect child demographic subgroups differentially. The study used an interrupted time-series methodology to measure differences in child dental use after adult dental benefit elimination and reinstatement. Monthly data came from Washington state Medicaid enrollee and dental claim files from January 2008 to December 2015. Medicaid-enrolled children with at least one Medicaid-enrolled adult in the same household were the intervention group, and Medicaid-enrolled children without a Medicaid-enrolled adult in the same household were the control group. The outcome was the monthly proportion of Medicaid-enrolled children with a dental examination per 10,000 Medicaid-enrolled children. After adult dental benefits elimination, dental examinations among children with Medicaid-enrolled adults in the same household gradually decreased, corresponding to 65 fewer dental examinations per 10,000 children per year (5.4 fewer dental examinations per 10,000 children per month; 95% confidence interval: -7.7, -3.1; P =0.006). Adult dental benefits had no effect on dental examination for children without a Medicaid-enrolled adult in the same household. Dental examinations for children with a Medicaid-enrolled adult in the same household continued to gradually decrease after adult benefits reinstatement. Children younger than age 6 were the most adversely impacted by changes to adult Medicaid dental benefits. Policymakers should consider the spillover effects and ethical considerations of eliminating adult Medicaid dental benefits on children's access to dental care.

Indonesian Dentists’ Perception of the Use of Teledentistry

IntroductionTeledentistry is the use of information and communication technology to provide dental services from distant locations. The use of teledentistry is highly beneficial in the COVID-19 pandemic era. ObjectiveThis study aimed to explore Indonesian dentists’ perceptions of the use of teledentistry in their daily practice and the benefits for patients. MethodsThis was a descriptive cross-sectional study comprising an electronic survey of Indonesian dentists. We used a cross-cultural, adapted questionnaire that consisted of 26 items and 5-point Likert scale questions that evaluated dentist perception in the following 4 domains: usefulness of teledentistry for dental practice, usefulness of teledentistry to improve practices, usefulness of teledentistry for patients, and dentists who had concerns about the use of teledentistry. ResultsA total of 652 dentists from 34 provinces in Indonesia participated in this study. The majority of respondents agreed about the usefulness of teledentistry in dental practice, especially for saving time, compared to referral letters (87%). Most respondents recognised the utility of teledentistry for improving dental practice and its benefits for patients. Nevertheless, most of the dentists had concerns about teledentistry in terms of digital forgery concern (74.2%) and technical incompatibility (71.8%). ConclusionsIndonesian dentists reported their positive perception of the usefulness of teledentistry for improving dental practice and benefits for patients, although some concerns were still present. Further studies on the application of teledentistry in Indonesia are still needed.

Xylitol-Containing Chewing Gum Reduces Cariogenic and Periodontopathic Bacteria in Dental Plaque—Microbiome Investigation

BackgroundDental caries and periodontal disease remain the most prevalent oral health problems in the world. Chewing xylitol gum may help reduce the risk of caries and periodontitis for dental health benefits. However, little evidence has shown healthy food estimation by sequencing 16S rDNA in oral microbial communities. This study investigated the clinical effect of xylitol chewing gum on dental plaque accumulation and microbiota composition using the PacBio full-length sequencing platform in 24 young adults (N = 24). The participants were randomly assigned to xylitol chewing gum and control (no chewing gum) groups. Participants in the chewing gum group chewed ten pieces of gum (a total of 6.2 g xylitol/day). Dental plaque from all teeth was collected for weighing, measuring the pH value, and analysis of microbial communities at the beginning (baseline, M0) and end of the 2-week (effect, M1) study period.ResultsThe results suggested a 20% reduction in dental plaque accumulation (p < 0.05) among participants chewing xylitol gum for 2 weeks, and the relative abundance of Firmicutes (a type of pathogenic bacteria associated with caries) decreased by 10.26% (p < 0.05) and that of Bacteroidetes and Actinobacteria (two types of pathogenic bacteria associated with periodontitis) decreased by 6.32% (p < 0.001) and 1.66% (p < 0.05), respectively. Moreover, the relative abundance of Fusobacteria was increased by 9.24% (p < 0.001), which has been proven to have a higher proportion in dental plaque of healthy adults. However, the dental plaque pH value stayed in a healthy range for the two groups.ConclusionIn conclusion, chewing xylitol gum would benefit cariogenic and periodontal bacterial reduction in the oral cavity, which could help to prevent the diseases related to these bacteria.

Did Expanded Dental Insurance Improve Chewing Ability in the Older Korean Population? Results of an Interrupted Time-series Analysis.

BackgroundIn 2012, the Korean National Health Insurance extended its coverage to include denture services for older adults. We examined whether the new policy resulted in improved chewing ability in the eligible population.MethodsWe used interrupted time-series (ITS) analysis, a quasi-experimental design, to analyze the effect of the policy. We used data from the Korea National Health and Nutrition Examination Survey conducted from 2007 to 2016–2018. The study population consisted of two groups: the treatment group, aged 65 years or older and eligible for the dental insurance benefit; and the control group, those younger than 65 years and ineligible. The main evaluated outcome was self-reported chewing difficulty.ResultsThe ITS analysis showed that chewing difficulty decreased annually by 0.93% (95% CI, −1.30 to −0.55%) and 0.38% (95% CI, −0.59 to −0.16%) after the policy extension in the older than 65 and younger than 65 groups, respectively. However, we could not conclude that the insurance extension affected chewing difficulty because there was a decrease in the control group as well.ConclusionChewing ability improved in both older and younger adults regardless of dental insurance coverage for older adults. Other exogenous factors probably led to the improvements in chewing ability as well as dental insurance benefits.

Impact of Medicaid dental coverage expansion on self-reported tooth loss in low-income adults

BackgroundLow-income adults delay oral health care due to cost more than any other health care service. These delays lead to caries, periodontal disease, and tooth loss. Expanding Medicaid dental coverage has increased dental visits, but the potential impact on previously unmet oral health needs is not well understood. MethodsIn this analysis, the authors estimated the association between Medicaid dental expansion and tooth loss. Data on self-reported tooth loss among adults below 138% federal poverty guideline were obtained from the Behavioral Risk Factor Surveillance System. A difference-in-differences regression was estimated. Additional analyses stratified according to age and separated extensive and limited dental benefits. ResultsExpanding Medicaid dental coverage is associated with increased probability of total tooth loss of 1 percentage point in the total sample, representing a 20% relative increase from the pre-expansion rate. This increase was concentrated in states offering extensive dental benefits and was largest (2.5-percentage-point greater likelihood) among adults aged 55 through 64 years for whom both extensive and limited dental benefits were associated with total tooth loss. ConclusionsMedicaid expansion with extensive dental benefits was associated with increased total tooth loss among low-income adults. This finding suggests that greater access to oral health care addressed previously unmet oral health needs for this population. Practical ImplicationsAs public dental coverage continues to expand, dental care professionals may find themselves treating a greater number of patients with substantial, previously unmet, oral health needs. Additional research to understand the long-term effects of Medicaid dental insurance for adults on their oral health is needed.

Ownership Change and Care Quality: Lessons From Minnesota's Experience With Value-Based Purchasing.

Background and ObjectivesMinnesota’s implementation of a new nursing home value-based reimbursement (VBR) system in 2016 presented an opportunity to compare the response of nursing homes (NHs) to financial incentives to improve their quality and efficiency. The state substantially increased reimbursement for care-related costs and tied this rate increase to a composite quality score. Coinciding with rate increases of the new VBR system was an increase in ownership changes, with new owners being primarily for-profit entities from outside of Minnesota, including several private equity firms. Our objective was to examine NHs that underwent a change in ownership to determine their cost and quality response to the change.Research Design and MethodsOur sample consists of 342 Minnesota NHs that submitted Medicaid cost reports each year from 2013 to 2019. A time differential two-way fixed-effects difference-in-difference model is used to assess changes in quality metrics by comparing measures in years prior to and years following the sale for NHs that changed ownership versus NHs with consistent ownership. Nursing home characteristics, revenue, and spending patterns are examined to understand differences in performance.ResultsThose NHs with ownership change experienced a decline in quality scores with notable changes to expenditure patterns. They performed worse on Minnesota Department of Health inspection scores and had nonsignificant declines in measures of quality of life and clinical care. They had declining staff dental and medical benefits and occupancy rates, greater revenue growth from Medicare Part B, and larger increases in administrative management fees.Discussion and ImplicationsMinnesota like many other states has given wide latitude for nursing home ownership changes, without specific oversight for the quality of care and expenditure patterns of new owners. Recommendations include strict guidelines for the transparency of ownership structures, quality performance targets, rigorous financial auditing, and enhanced regulatory oversight.

Association of Changes in Medicaid Dental Benefits With Localized Diagnosis of Oral Cavity Cancer

This cohort study uses data from the Surveillance, Epidemiology, and End Results database to examine the association between changes in Medicaid dental insurance coverage in California between 2009 and 2014 and rates of localized oral cavity cancer diagnoses.

Epidemiological evaluation of the outcomes of initial root canal therapy in permanent teeth of a publicly insured paediatric population.

Background:Previously published epidemiological outcome studies of nonsurgical root canal therapy (NSRCT) in the United States utilize data only from a single, private dental insurer for adult populations.Aim:This study aimed to investigate the outcomes of initial NSRCT, performed on permanent teeth, in a publicly insured paediatric population.Design:New York State Medicaid administrative claims were used to follow 77 741 endodontic procedures in 51 545 patients aged 6–18, from the time of initial NSRCT until the occurrence of an untoward event (retreatment, apicoectomy, and extraction). The initial treatment and untoward events were identified by Current Dental Terminology codes. The Kaplan–Meier survival estimates were calculated at 1, 3, and 5 years. Hazard ratios for time to permanent restoration and restoration type were calculated using the Cox proportional hazards model.Results:The median follow-up time was 44 months [range: 12–158 months]. Procedural, NSRCT, survival was 98% at 1 year, 93% at 3 years, and 88% at 5 years. Extraction was the most common untoward event. Teeth permanently restored with cuspal coverage had the most favorable treatment outcomes.Conclusions:Overall, 89% of teeth were retained and remained functional over a minimum follow-up time of 5 years. These results elucidate the expected outcomes of NSRCT in permanent teeth for paediatric patients with public-payer dental benefits.

Has the Child Dental Benefits Schedule improved access to dental care for Australian children?

The Child Dental Benefits Schedule (CDBS) is an ongoing scheme administered through the Australian Government providing eligible children funding for clinical dental treatment. This study aimed to investigate the access of dental services across children's early childhood and examine whether the CDBS has improved access to dental care. The longitudinal study of Australian children is an ongoing cross-sequential cohort study with a representative sample of Australian children recruited in 2004. Birth (0-1year) and kindergarten (4-5years) cohorts were recruited through Medicare enrolment information at baseline and were representative of the Australian child population. Population-weighted longitudinal mixed effects Poisson models with individual identifiers as a random effect were used to assess the effect of Medicare dental schedules on reported dental attendance. Prior to the implementation of the CDBS for both cohorts, the birth cohort reported the lowest attendance rate at age 4-5. The introduction of the CDBS increased the rate of dental attendance for the low household income group by 8% (95% CI: 1%, 15%) after adjusting for confounders. The model provides evidence that dental attendance increased with age and the Indigenous population have 31% (95% CI: 4%, 55%) lower attendance rate after adjustment. The increase in reported access to dental services and favourable visiting patterns in low-income households during the operation of the CDBS provides some evidence that the schedule's primary aims to improve access to care in the child population are being met. Access to healthcare is multifaceted and the underutilisation of the schedule in the population warrants review of the schedule performance using other patient-centred indicators.

Qualitative evaluation of the pre-implementation phase of a rural dental clinic co-located within a health center in the Pacific Northwest of the United States.

The development of a dental clinic within an existing Rural Health Clinic (RHC) was proposed to improve access to dental care for Medicaid enrollees in Washington. This qualitative study assessed the implementation of a co-located dental clinic in a rural community during the pre-implementation phase. Additionally, we sought to determine the needs and expectations of community members living in this rural Washington county. This study took place in Jefferson County, Washington, aDental Health Professional Shortage Area.Semi-structured interviews were conducted with 42 participants, consisting of administrators (n=9), health providers (n=9) and community members (n=24). Administrators and health providers were interviewed by phone. Community members were interviewed in-person at Jefferson Healthcare primary care clinics or by phone. Interview data were deductively coded, and thematic analysis with a hybrid inductive-deductive approach was used to analyse coded data. Five themes were identified regarding local needs and expectations: dental care as a major need in the community, persisting barriers to dental care access, expecting more than a 'Medicaid experience', visions for a clinic that serves the community, and solutions outside the clinic to improve community oral health. By improving access to dental care, a co-located dental clinic is helping to address general dental care needs in rural communities. Policy-level solutions that address housing and food insecurity, improve public transportation, and retain and expand low-income adult Medicaid dental benefits may be needed to overcome persisting barriers to oral health.

Racial And Ethnic Disparities In Dental Services Use Declined After Medicaid Adult Dental Coverage Expansions.

Racial and ethnic disparities in adults' access to dental care have persisted for decades. We examined how recent Affordable Care Act Medicaid expansions that included coverage of dental services for adults affected racial and ethnic disparities in dental services use. Using Medical Expenditure Panel Survey data from the period 2011-18, we compared changes in dental services use for low-income non-Hispanic Black and Hispanic adults with changes in use for low-income non-Hispanic White adults. We found that expansions including extensive dental benefits were associated with narrowed racial and ethnic disparities in dental care visits and use of preventive and treatment services. For non-Hispanic Black and Hispanic adults, after Medicaid expansion with extensive dental benefits there was an 8-percentage-point increase in their likelihood of dental visits in a given year when compared with non-Hispanic White adults. This represents a reduction from preexpansion disparities by 75percent for non-Hispanic Black adults and 50percent for Hispanic adults. This disparity decline is due to both an increase in dental services use among non-Hispanic Black and Hispanic adults and little change occurring among non-Hispanic White adults. In contrast, no decline in disparities was seen in states with less generous dental benefits. Overall, rates of dental care among low-income adults continue to be low across racial and ethnic groups, indicating other key access barriers to dental care and persistent unmet oral health needs.

Factors associated with women's autonomy regarding dental health care utilization in Bengaluru - A cross sectional study

Background: Preventive dental care benefits people of all ages and genders' oral health. Among many conceptual implications, autonomy suggests the power to alter one's fate and environment, among other things. Little is known about women's autonomy and factors influencing dental health-care utilization in India. This study was designed to assess knowledge, attitude, and oral hygiene practices and its association with women's autonomy and dental care utilization. Materials and Methods: A cross-sectional study was conducted among 400 women aged 18 years or older in Bengaluru Urban District. Questionnaires were employed to assess women's autonomy, knowledge, attitude, oral hygiene practices, and dental care service utilization. Descriptive statistics and bivariate and regression analyses were carried out. The P < 0.05 was considered statistically significant. Results: More than half of the women (61.3%) had a high level of autonomy. Women with a high level of autonomy had more knowledge, a more positive attitude, and better dental hygiene habits. Autonomy, knowledge, and attitude were all significant independent predictors of women's use of dental care services. Conclusions: Women's autonomy was found to influence knowledge, attitude, and oral hygiene practices which in turn are associated with dental health-care service utilization.

Medicare Must Provide Additional Cost and Access Information to Enhance Decision Making Around Trade Offs Between Medicare Advantage and Medigap.

Health insurance coverage options are complicated and often leave Medicare beneficiaries, families, advocates, and brokers confused. Medicare should make small changes to its existing “Compare Coverage Options” tool that would enhance the public’s understanding of the trade-offs between Medicare Advantage and supplemental Medigap with Fee-for-Service Medicare. For cost considerations, Medicare should include a projection of annual out-of-pocket (OOP) spending, whether an OOP cap applies and whether the ability to alter OOP for additional clinical benefit is offered. For access considerations, Medicare should provide access to information to educate the public on coverage and costs associated with dental, vision, and hearing benefits, network adequacy, prior authorization, and supplemental benefits. These changes will enhance transparency and decision making.

Oral Hygiene Practice among 18-year-old Norwegian Adolescents Using Health Belief Model: A Cross-Sectional Study.

Objectives The aim was to compare oral hygiene practice (brushing/flossing) among 18 years old from two regions, Hordaland County, Norway, and possible perceptional correlates using the Health Belief Model. Materials and Methods The participants from six municipalities from the south district with high prevalence of dental caries to six municipalities from the rest of Hordaland county, with low prevalence of dental caries (control), using a web-based questionnaire. Statistical analyses: the Mann–Whitney U test was used and the t -test for independent samples. Bivariate and logistic regression analyses to examine associations. Results A total of 416 people participated. The south district’s participants had lesser percentage brushing twice a day and flossing at least once a day, they significantly visited lesser the dental service, perceived more susceptibility to dental caries, and lower benefits of brushing/flossing compared with the controls. Girls (odds ratio [OR]: 0.34) who perceived higher severity of dental caries (OR: 1.86), higher self-identity (OR: 2.14), and lesser barriers to brushing (OR: 0.14) had higher odds to brushing twice a day compared with their counterparts. Girls (OR: 0.34) who perceived higher severity of dental caries (OR: 2.34), higher benefits (OR = 2.8), and lesser barriers to flossing (OR = 0.23) had higher odds to flossing at least once a day compared with their counterparts. Conclusion South district’s participants significantly had some of risk factors to the recommended brushing/flossing practice compared with the control and these might help in explaining the difference in oral hygiene practice.

PP290 Ongoing Swedish Initiatives To Improve The Potential For Real World Data Assessment Of Medical Devices

IntroductionIn 2020, the Swedish regions cemented a national managed-introduction project for medical devices, to ensure equal, cost-effective, and appropriate use. Health technology assessment (HTA) is an important component of the project. Swedish national health registers have world-class coverage and completeness but may lack information enabling adequate evaluation of medical devices. This study reviews the current situation and ongoing initiatives. Additionally, the potential for medical device health economics and outcomes research (HEOR) using Swedish registers is assessed.MethodsA review of Swedish national health registers was undertaken, focusing on available data, and contextualized for the purpose of HEOR for medical devices. Additionally, the review included an evaluation of the Swedish reimbursement authority's (The Dental and Pharmaceutical Benefits Agency, TLV) ongoing initiatives to improve the potential to follow-up the impact of the technologies they assess and develop value-based pricing schemes.ResultsFive registers were deemed the most relevant national health registers for device research. They include high-quality longitudinal data and are linkable on a per-patient basis. For devices, main limitations include limited data on specialized outpatient care, lags in updating certain registers, lack of laboratory data, and challenges in identifying the specific device used. Reports indicate that certain limitations are being addressed, including pilot-studies investigating the opportunity for automated reporting of data from regional systems, and app-collected patient-reported health data.ConclusionsSwedish registers provide comprehensive sources for HEOR studies, but limitations related to the assessment of medical device impact remain. As is common with register data reporting grouped diagnoses and interventions, specific devices are not directly identifiable in the national health registers. For some devices, this might be addressable through linkage with other data-sources. Swedish authorities are undertaking several initiatives that will likely improve the potential for HTA and follow-up of medical devices using national health register data.

Silver Diamine Fluoride- The New Black Magic

Silver diamine fluoride combines the remineralizing effects of fluoride and the antibacterial effects of silver and thus provides an alternative care path for those patients in whom traditional restorative treatment cannot be done. Many countries have recommended the use of 38% SDF for caries prevention as well as for caries arrest. SDF is proved to be more efficient as caries preventive tool when compared to fluoride varnishes and APF Gel. Other dental benefits of SDF continue to be researched and discussed in the literature. However, SDF- related black staining is of prime concern while using it in aesthetic zone. No serious adverse effects of using SDF have been reported in dentistry. SDF is safe, effective, and cost-friendly agent. We can hope that it can meet both the AAPD and ISPPD vision and mission to advance optimal oral health for all children through prevention, involvement of the society and other necessary measures.

Proteomics of Streptococcus mutans to Reveal the Antibiofilm Formation Mechanism of Ag/ZnO Nanocomposites with Light-Emitting Diode Radiation.

IntroductionAs a biofilm-associated disease, dental caries benefits from nanoparticle (NP)-based therapies. Streptococcus mutans (S. mutans) is a primary aetiologic agent for dental caries development. We successfully applied a synergistic therapy of Ag/ZnO nanocomposites combined with light-emitting diode (LED) radiation to inhibit S. mutans biofilms. However, the antibiofilm mechanism has not been fully elucidated, and little is known about the biofilm formation ability of bacteria that survive NP-based therapies.MethodsThis study explored the antibiofilm formation mechanism of this synergistic therapy by an integrated approach based upon proteomics.ResultsSynergistic therapy killed 99.8% of bacteria, while the biofilm formation ability of 0.2% surviving bacteria was inhibited. The proteomic responses of S. mutans to synergistic therapy were comprehensively characterized to unveil the mechanism of bacterial death and biofilm formation inhibition of the surviving bacteria. In total, 55 differentially expressed proteins (12 upregulated and 43 downregulated) were recorded. The bioinformatic analysis demonstrated that cellular integrity damage and regulated expression of structure-associated proteins were the main reasons for bacterial death. In addition, the proteomic study indicated the potential inhibition of metabolism in surviving bacteria and provided a biofilm-related network consisting of 17 differentially expressed proteins, explaining the multiantibiofilm formation actions. Finally, we reported and verified the inhibitory effects of synergistic therapy on sucrose metabolism and D-alanine metabolism, which disturbed the biofilm formation of surviving bacteria.ConclusionOur findings demonstrated that synergistic therapy killed most bacteria and inhibited the surviving bacteria from forming biofilms. Furthermore, the antibiofilm formation mechanism was revealed by proteomics analysis of S. mutans after synergistic therapy and subsequent metabolic studies. Our success may provide a showcase to explore the antibiofilm formation mechanism of NP-based therapies using proteomic studies.

Employer-sponsored Insurance Including Dental Benefits

Employer-sponsored Insurance Including Dental Benefits

Oral Health Knowledge, Barriers to Dental Care, and Awareness of a Medicaid Pregnancy Dental Coverage Among Reproductive-Age Women.

Objectives: Oral health is an integral part of women's health, yet many women face barriers and go without necessary dental care. The objectives of this study were to (1) examine and compare pregnancy-related oral health knowledge and barriers to dental care access during pregnancy among women with private and public insurance and (2) estimate awareness of available Medicaid pregnancy dental benefit among Medicaid-enrolled women and explore associated factors. Methods: A cross-sectional survey was administered to a convenience sample of 21- to 45-year-old women (n = 187) visiting a large urban academic health center in Virginia. Data on pregnancy-related oral health knowledge, barriers to dental care access, Medicaid dental benefit awareness, health insurance, socio-demographics, health information source, and last dental visit were collected. Chi-square tests, t-tests, and multivariable regression were used to examine associations at p ≤ 0.05. Results: More than half of the women reported private insurance (52.4%), 40.3% reported Medicaid, and 8.3% reported being uninsured. Medicaid-enrolled women reported a lower prevalence of a routine dental checkup in the past year (44% vs. 71%, p = 0.002), lower knowledge scores (2.9 vs. 3.6, p < 0.001), and more barriers to accessing dental care during pregnancy compared with privately insured women. One in every three Medicaid-enrolled women (34%) was unaware of the Medicaid pregnancy dental benefit. Benefit awareness was associated with the receipt of health information from a health care source (p = 0.030) and a high oral health knowledge score (p = 0.018). Conclusions: There was a significant gap in dental care use and knowledge between Medicaid-enrolled and private-insured women in our study sample. Targeted programs should be developed to educate women about the importance of oral health and share information about available Medicaid dental coverage to reduce barriers to dental care during pregnancy.

WATER QUALITY ANALYSIS FOR FLUORIDE CONCENTRATION IN FLUORIDATED DRINKING WATER DISTRIBUTION SYSTEM VIA HYDRAULIC SIMULATION

Drinking water quality monitoring is compulsory in order to ensure that it does not pose any harm to the public health. Water fluoridation is aimed to provide sufficient amount of fluoride in the drinking water for the consumer dental health benefit. In this study, EPANET software was used to model the water distribution network from a specific water treatment plant and later to simulate the hydraulic and water quality analysis for the system. From the simulation and modeling of the water distribution network, the hydraulic simulation and water quality behavior for fluoride concentration of each nodes and links in the drinking water distribution network were found to change over time following the drinking water distribution segment. From the hydraulic simulation, especially for head and flow at a particular point in time, it consists of simultaneous solution of flow equivalence for every junction and headloss relationship in every link of network as a result of hydraulic balancing. In the water distribution network, every pipe in a network made up a single segment, where the water quality was proportional to its initial quality set at the starting node. In conclusion, the hydraulic status of the physical and non-physical components of the water distribution network found to have a significant impact on the fluoride content of drinking water.