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A double-blind controlled trial initiated in 1944 has led to the common narrative that a 10-mg daily vitamin C intake is adequate to prevent and treat impaired wound healing, and by inference, other collagen-related diseases such as heart disease or stroke. The WHO relies on this narrative to set the recommended nutrient intake for vitamin C. This narrative, however, is based on what is known as the eyeball method of data assessment. The 1944 trial published individual participant data on scar strength providing an opportunity to statistically probe the validity of the 10-mg narrative, something which has not yet been done. The findings show that a vitamin C intake that averages to 10 mg/d over a mean follow-up of 11.5 mo was associated with a 42% weakened scar strength when compared with 80 mg vitamin C intake/d (P < 0.001). The observed dose-response curve between scar strength and vitamin C intake suggests that the daily vitamin C intake needed to prevent collagen-related pathologies is in the range recommended by the National Academy of Medicine and the European Food Safety Authority (75 to 110 mg/d), not the WHO recommendation (45 mg/d). The findings also show that a vitamin C intake that averages to 65 mg/d over a mean follow-up of 6.5 mo failed to restore the normal wound-healing capacity of vitamin C-depleted tissues; such tissues had a 49% weaker scar strength when compared with nondepleted tissues (P < 0.05). Thus, average daily vitamin C intakes ∼50% higher than the WHO recommends may fail to treat existing collagen-related pathologies. It is concluded that the prior lack of statistical analyses of a landmark trial may have led to a misleading narrative on the vitamin C needs for the prevention and treatment of collagen-related pathologies.

Article Title and Bibliographic Information Relationship between periodontal disease and lung cancer: A systematic review and meta-analysis. Wang J, Yang X, Zou X, Zhang Y, Wang J, Wang Y. J Periodontal Res. 2020 Oct;55(5):581–593. doi: 10.1111/jre.12772 . Epub 2020 Jun 25. PMID: 32,583,879. Source of Funding National Natural Science Foundation of China and Scientific Research foundation of the Health Planning Committee of Sichuan. Type of Study/Design Systematic review with meta-analysis of cohort and case-control studies.

Background The authors sought to determine associations between serum vitamin D levels and dental caries in noninstitutionalized children aged 5 to 12 years in the United States. Methods The authors used National Health and Nutrition Examination Survey, 2005-2006, data to study childhood caries and vitamin D. Vitamin D deficiency and inadequacy were defined as serum 25-hydroxyvitamin D (25[OH]D) less than 30 nanomoles per liter and between 30 and 49 nmol/L, respectively. Associations between vitamin D and caries experience (a combined measure of untreated caries or restorations) were examined after adjustment for confounders using multivariate logistic regression at a critical value of 5%. Sample weights were used to generate nationally representative estimates. Results The overall prevalence of serum 25(OH)D less than 30 nmol/L and 25(OH)D between 30 and 49 nmol/L among 5- to 12-year-olds was 3% and 16%, respectively. Prevalence of 25(OH)D less than 30 nmol/L and 25(OH)D between 30 and 49 nmol/L among children with caries experience was 2% and 16%, respectively. Multivariate logistic regression analysis found no significant association between vitamin D and caries experience ( P = .78). Furthermore, this association was not significant after adjusting for age, sex, race and ethnicity, ratio of family income to poverty threshold, and sugar consumption ( P = .46). Conclusions The authors did not find a significant association between 25(OH)D status and caries experience in US children who participated in NHANES, 2005-2006. Practical Implications The authors’ findings do not support existing evidence of an association between caries and vitamin D.

Background A panel of experts convened by the American Dental Association Council on Scientific Affairs presents an evidence-based clinical practice guideline on nonsurgical treatment of patients with chronic periodontitis by means of scaling and root planing (SRP) with or without adjuncts. Methods The authors developed this clinical practice guideline according to the American Dental Association's evidence-based guideline development methodology. This guideline is founded on a systematic review of the evidence that included 72 research articles providing clinical attachment level data on trials of at least 6 months' duration and published in English through July 2014. The strength of each recommendation ( strong , in favor , weak , expert opinion for , expert opinion against , and against ) is based on an assessment of the level of certainty in the evidence for the treatment's benefit in combination with an assessment of the balance between the magnitude of the benefit and the potential for adverse effects. Practical Implications and Conclusions For patients with chronic periodontitis, SRP showed a moderate benefit, and the benefits were judged to outweigh potential adverse effects. The authors voted in favor of SRP as the initial nonsurgical treatment for chronic periodontitis. Although systemic subantimicrobial-dose doxycycline and systemic antimicrobials showed similar magnitudes of benefits as adjunctive therapies to SRP, they were recommended at different strengths ( in favor for systemic subantimicrobial-dose doxycycline and weak for systemic antimicrobials) because of the higher potential for adverse effects with higher doses of antimicrobials. The strengths of 2 other recommendations are weak : chlorhexidine chips and photodynamic therapy with a diode laser. Recommendations for the other local antimicrobials (doxycycline hyclate gel and minocycline microspheres) were expert opinion for . Recommendations for the nonsurgical use of other lasers as SRP adjuncts were limited to expert opinion against because there was uncertainty regarding their clinical benefits and benefit-to-adverse effects balance. Note that expert opinion for does not imply endorsement but instead signifies that evidence is lacking and the level of certainty in the evidence is low.

Background A panel of experts convened by the American Dental Association (ADA) Council on Scientific Affairs presents evidence-based clinical recommendations regarding professionally applied and prescription-strength, home-use topical fluoride agents for caries prevention. These recommendations are an update of the 2006 ADA recommendations regarding professionally applied topical fluoride and were developed by using a new process that includes conducting a systematic review of primary studies.

Introduction Anterior open-bite (AOB) treatment is considered challenging because of difficulties in determining and addressing etiologic factors and the potential for relapse in the vertical dimension after treatment. In this review, we compiled evidence on the long-term stability of the major therapeutic interventions for correcting AOB. Our objective was to review and compile evidence for the stability of surgical and nonsurgical therapies for AOB malocclusion. Our data sources were PubMed, EMBASE, Cochrane Library, limited gray literature search, and hand searching. Methods A search was performed of the electronic health literature on the stability of AOB after treatment. Hand searching of major orthodontic journals and limited gray literature searching was also performed, and all pertinent abstracts were reviewed for inclusion. Full articles were retrieved for abstracts or titles that met the initial inclusion criteria or lacked sufficient detail for immediate exclusion. Studies accepted for analysis were reviewed and their relevant data retrieved for pooling. The long-term stability estimates were pooled into nonsurgical and surgical groups, and summary statistics were generated. Results One hundred five abstracts met the initial search criteria, and 21 articles were included in final analyses. Rejected articles failed to exhibit follow-up times of 12 months or more, did not include measurements of overbite (OB), or did not meet inclusion criteria. All included articles were divided into a surgical group (SX) with a mean age of 23.3 years and a nonsurgical group (NSX) with a mean age of 16.4 years. All studies were case series. Random-effects statistical models were used to pool the mean OB measures before and after treatment and also at the long-term follow-up. The pretreatment adjusted means of OB were –2.8 mm for the SX and –2.5 mm for the NSX. AOB closures up to +1.6 mm (SX) and +1.4 mm (NSX) were achieved. Relapse in the SX group during the mean 3.5 years of follow-up reduced the OB to +1.3 mm; the NSX group relapsed to +0.8 mm in the mean 3.2 years of follow-up. Pooled results indicated reasonable stability of both the SX (82%) and NSX (75%) treatments of AOB measured by positive OB at 12 or more months after the treatment interventions. Conclusions In the included case series publications, success of both the SX and NSX treatments of AOB appeared to be greater than 75%. Because the SX and the NSX were examined in different studies and applied to different clinical populations, no direct assessment of comparative effectiveness was possible. The pooled results should be viewed with caution because of the lack of within-study control groups and the variability among studies.

Background This article presents evidence-based clinical recommendations regarding the intake of fluoride from reconstituted infant formula and its potential association with enamel fluorosis. The recommendations were developed by an expert panel convened by the American Dental Association (ADA) Council on Scientific Affairs (CSA). The panel addressed the following question: Is consumption of infant formula reconstituted with water that contains various concentrations of fluoride by infants from birth to age 12 months associated with an increased risk of developing enamel fluorosis in the permanent dentition? Types of Studies Reviewed A panel of experts convened by the ADA CSA, in collaboration with staff of the ADA Center for Evidence-based Dentistry (CEBD), conducted a MEDLINE search to identify systematic reviews and clinical studies published since the systematic reviews were conducted that addressed the review question. Results CEBD staff identified one systematic review and two clinical studies. The panel reviewed this evidence to develop recommendations. Clinical Implications The panel suggested that when dentists advise parents and caregivers of infants who consume powdered or liquid concentrate infant formula as the main source of nutrition, they can suggest the continued use of powdered or liquid concentrate infant formulas reconstituted with optimally fluoridated drinking water while being cognizant of the potential risks of enamel fluorosis development. These recommendations are presented as a resource to be considered in the clinical decision-making process. As part of the evidence-based approach to care, these clinical recommendations should be integrated with the practitioner's professional judgment and the patient's needs and preferences.

Background Researchers have considered infant formula consumption a potential risk factor for enamel fluorosis in the U.S. population. The authors conducted a systematic review of controlled studies regarding the risk of developing enamel fluorosis associated with use of infant formula. Methods One reviewer independently conducted systematic searches in eight databases. The authors then abstracted information, assessed study quality and combined odds ratios (ORs), when obtainable, by using a random-effects model. Results After evaluating 969 potentially eligible published studies, the reviewers found that the authors of 41 studies had evaluated the effect of infant formula on enamel fluorosis risk. Authors of 14 of the 41 studies did not report their findings in their results. The authors of the remaining 27 published studies reported the findings of 19 observational studies; authors of 17 of these 19 studies reported ORs and, among these, infant formula consumption was associated with a higher prevalence of enamel fluorosis in the permanent dentition (summary OR 1.8, 95 percent confidence interval [CI] 1.4–2.3). There was significant heterogeneity among studies (I 2 66 percent) and evidence of publication bias ( P = .002). A metaregression analysis indicated that the ORs associating infant formula with enamel fluorosis increased by 5 percent for each 0.1–part-per-million increase in the reported levels of fluoride in the water supply (OR 1.05, 95 percent CI 1.02–1.09). Clinical Implications Infant formula consumption may be associated with an increased risk of developing at least some detectable level of enamel fluorosis, which depends on the level of fluoride in the water supply. The evidence that the fluoride in the infant formula caused enamel fluorosis was weak, as other mechanisms could explain the observed association.

Translating basic science evidence into clinical trials is particularly challenging. The term translationist can refer to an individual who translates evidence into clinical action or an individual who has to choose the most promising intervention among alternatives and move it forward toward definitive randomized clinical trials. With respect to the first type of translationist, translating evidence into clinical action is most promising when there is unequivocal evidence that an intervention provides tangible patient benefits, preferably from rigorously designed randomized trials based on true end points. In the absence of such evidence, translation is challenging and can cause more harm than good, as has been illustrated by the rise and fall of treatments such as hormone replacement therapy, antioxidants, and temporomandibular joint implants. With respect to the second type of translationist, picking a most promising scientific finding and moving it toward clinical trials can be challenging; the future is inherently unpredictable and the value of major innovations—including medical innovations—often remains unrecognized at the time of discovery. Sound epidemiology, mechanistic studies on methods of action, and a comprehensive series of exploratory trials may help in improving the translation of promising findings to unequivocal evidence. Whether such suggestions on identifying promising treatments will lead to a larger success rate in successful translation remains to be determined. TRANSLATING EVIDENCE INTO PRACTICE

Background Orthodontic therapy has been suggested to lead to an improved periodontal status through mechanisms such as increased ease of plaque removal and reduced occlusal trauma. The objective of the authors' systematic review was to compare contemporary orthodontic treatment with no intervention, by means of evaluating periodontal outcomes measured after end of treatment. Methods The authors completed electronic searches in eight databases (1980–2006) and hand searches in six dental journals (1980–2006). They extracted data using standardized forms and calculated weighted mean differences. Results Weak evidence from one randomized study and 11 nonrandomized studies suggested that orthodontic therapy was associated with 0.03 millimeters of gingival recession (95 percent confidence interval [CI], 0.01–0.04), 0.13 mm of alveolar bone loss (95 percent CI, 0.07–0.20) and 0.23 mm of increased pocket depth (95 percent CI, 0.15–0.30) when compared with no treatment. The effects of orthodontic therapy on gingivitis and attachment loss were inconsistent across studies. Conclusions This systematic review identified an absence of reliable evidence describing positive effects of orthodontic treatment on periodontal health. The existing evidence suggests that orthodontic therapy results in small detrimental effects to the periodontium.

Introduction: The high prevalence of orthodontic treatment in young people makes the associated radiation to the head and neck of potential public-health significance. In this study, we estimated secular changes (1963-2003) in age-specific organ doses associated with orthodontic care and collective organ doses in the United States in 1999. Methods: A survey of radiographic records at 1 university clinic was combined with published estimates to provide organ-specific radiation doses. Collective organ doses were estimated from the 1999 US Nationwide Evaluation of X-ray Trends and published orthodontic utilization surveys. Results: Before 1992, orthodontic care in a university setting was associated with mean doses of 7.0 milligrays (mGy) to the thyroid, 0.8 mGy to the red bone marrow, 2.7 mGy to the brain, 13.2 mGy to the salivary glands, and 5.1 mGy to the bone. After 1992, the doses decreased to 2.8 mGy to the thyroid, 0.3 mGy to the red bone marrow, 0.7 mGy to the brain, 6.2 mGy to the saliva glands, and 2.4 mGy to the bone. Around 1999, the collective doses associated with orthodontic care in the United States in patients less than 19 years of age were 400 Gy to the red bone marrow and 3800 Gy to the thyroid. Conclusions: Orthodontic care, in part due to its high prevalence, potentially contributes significantly to the diagnostic radiation burden in those less than 19 years old in the United States.

The determination of clinical significance is a process of comparing therapeutic results to a subjectively derived set of criteria. Different persons often reach different decisions when presented with the same evidence regarding the benefits and harms associated with a treatment. Traditionally, clinical significance has been a yes-or-no decision. The purpose of this article is to add more structure to the process, by transforming a yes-or-no decision to a categorical decision. We propose to define 4 levels of clinical significance on the basis of the nature of the anticipated benefits (tangible versus intangible) and the likelihood for obtaining the benefit (large versus small). Rating the clinical significance of a treatment on a categorical basis may provide a useful tool to efficiently communicate the degree of belief in the benefit of a therapy.

Recent advances in technology have led to the availability of sequential removable orthodontic appliances (aligners) to move teeth in a stepwise fashion (Invisalign, Align Technology, Santa Clara, Calif). This study was undertaken to compare 2 distinctly different materials (hard and soft) and 2 activation frequencies (1 week and 2 weeks) for this technique. Fifty-one subjects, stratified by peer assessment rating (PAR) and need for extractions, were randomly assigned to a hard or a soft plastic appliance, and a 1-week or 2-week activation time. The primary endpoint was the completion of the initially prescribed series of aligners. Changing aligners every other week was more likely to lead to completion of the initial series of aligners than changing aligners weekly (37% vs 21%). No substantial difference in the completion rate was observed for the soft versus the hard appliance (27% vs. 32%). The completion rate was highest (46%) among patients with PAR scores less than 15 and no planned extractions, and lowest (0%) among subjects who had 2 or more premolars extracted. All who completed their initial series of aligners required an additional series of aligners or fixed appliances to achieve the original treatment goals. This exploratory study suggests that subjects with a 2-week activation regimen, no extractions, and a low PAR score are more likely to complete their initial series of aligners.

Fifty-one patients were enrolled in this study to explore the treatment effects of material stiffness and frequency of appliance change when using clear, sequential, removable appliances (aligners). Patients were stratified based on pretreatment peer assessment rating (PAR) scores and need for extractions. They were randomized into 4 treatment protocols: 1-week activation with soft material, 1-week activation with hard material, 2-week activation with soft material, and 2-week activation with hard material. Patients continued with their protocols until either the series of aligners was completed, or until it was determined that the aligner was not fitting well (study end point). Weighted PAR score and average incisor irregularity (AII) indexes were used to measure pretreatment and end-point study models, and average improvement was compared among the 4 groups. In addition to the evaluation of the 4 treatment groups, comparisons were made of the individual components of the PAR score to determine which occlusal components experienced the most correction with the aligners. The percentages and absolute extraction space closures were evaluated, and papillary bleeding scores before and during treatment were compared. Although no statistical difference was observed between the 4 treatment groups, a trend was noted with the 2-week frequency having a larger percentage of reduction in weighted PAR and AII scores, and greater extraction space closure. Anterior alignment was the most improved component, and buccal occlusion was the least improved. When analyzed by type of extraction, incisor extraction sites had a significantly greater percentage of closure than either maxillary or mandibular premolar extraction sites. A statistically significant decrease in mean average papillary bleeding score was found during treatment when compared with pretreatment scores, although this difference was not clinically significant.

Background and Overview Observational investigations provide an opportunity to document the distribution of diseases in various populations and to explore correlations between exposures and outcomes. Interpreting such correlations as causal is challenging and can lead to more harm than good when used as a basis for advising lifestyle changes or interventions to healthy people. The aim of this review is to provide a brief introduction to observational study designs and describe some of their strengths and weaknesses. Conclusions and Practice Implications Observational findings can be useful to guide clinical research, but often they do not provide a reliable basis for clinical decision making. Caution in applying observational findings to clinical practice is particularly important when caring for healthy people.

Background Chronic periodontitis, or CP, has been associated with coronary heart disease, or CHD. This article reviews the available prospective CP-CHD evidence. Literature Reviewed In nine cohort studies, CP was associated with a 15 percent greater risk of developing CHD. Conclusions from individual studies depended on study characteristics. Summary risk estimates for studies controlling for smoking intensity (five of nine studies) or health awareness (two of nine studies) or studies with more than 600 CHD events (three of nine studies) suggest that CP is either not at all or weakly associated with CHD. Summary risk estimates for the studies that did not control for these factors or that examined an insufficient number of CHD events reported a weak increase in CHD risk associated with CP (20 percent greater). These data suggest that the CP-CHD associations observed in smaller studies are due to insufficient control for lifestyle differences. In addition, one cohort study reported that edentulous people had a CHD risk similar to that of people with CP. Therefore, the plausibility of dental infection elimination affecting CHD risk appears limited. Summary Current evidence supporting a causal CP-CHD link is weak. Rigorous methodological and analytical control of lifestyle factors such as smoking will be required to elucidate whether the CP-CHD disease association is either small or nonexistent. Clinical Implications Cigarette smoking destroys both oral and systemic health. Because of this strong common causal factor, oral and systemic health are linked. Dentistry should continue to play an important role in implementing smoking prevention and cessation programs.

Background While it has been suggested that periodontal disease may be associated with coronary heart disease, or CHD, there are no data to suggest that the elimination of chronic dental infections actually lowers the risk of developing chronic CHD. The goal of this study was to determine whether people with a definitive elimination of all potential dental infections—edentulous people, who are at the optimum endpoint of dental infection elimination from a CHD perspective—lower their CHD risk over time when compared with people who have a specific dental infection, periodontitis. Methods The authors examined data from a prospective cohort of 4,027 people who participated in the First National Health and Nutrition Examination Survey, or NHANES I, Epidemiologic Follow-up Study. The primary outcome measure was the first CHD event. Results During a mean follow-up of 17 years, there were 1,238 CHD events (538 fatal). The confirmed elimination of chronic dental infections did not lead to a decreased risk of experiencing a CHD event (relative risk, 1.02; 95 percent confidence interval, 0.86–1.21). The CHD risk among people with and without chronic dental infections remained constant over time with respect to each other (test for increasing or decreasing trend over time: not significant, χ 2 1 = 0.48; P = .93). Conclusions People who had a complete, definitive and long-term elimination of all potential dental infections through extraction of all teeth did not have lower CHD risk when compared with people with diagnosed periodontitis. Clinical Implications Until evidence is found to the contrary, the authors suggest that prevention of CHD should not be used as the basis for recommending treatment to eliminate chronic dental infections.

Objectives. The purpose of this case-control study was to determine whether the radiographic appearance of the mandibular cortical bone in patients who were elderly and noninstitutionalized was related to a self-reported history of osteoporotic fractures. Study Design. Patients who had a billing statement at the School of Dentistry dated between 1993 and 1996, who were older than 60, and who had a panoramic radiograph were invited to be interviewed regarding fracture history (circumstances and year of fracture) and risk factors for osteoporosis. Cases (n = 93) were individuals reporting osteoporotic fractures (fractures occurring after minor impact). Controls (n = 394) were individuals reporting traumatic fractures (n = 105) or no fractures (n = 289). Blinded to case-control status, we evaluated the mandibular cortex on a panoramic radiograph and classified them as normal (even and sharp endosteal margin), moderately eroded (evidence of lacunar resorption or endosteal cortical residues), or severely eroded (unequivocal porosity). In addition, cortical thickness was measured below the mental foramen. Results. After adjustment for potentially confounding factors, the odds ratio for an osteoporotic fracture associated with moderately eroded and severely eroded mandibular cortices was 2.0 (95% CI, 1.2 to 3.3) and 8.0 (95% CI, 2.0 to 28.9), respectively. After adjusting for all potentially confounding factors, we found that the cortex was 0.54 mm (or 12%) thinner in subjects with an osteoporotic fracture compared with controls (95% CI, 0.25 to 0.84 mm). Conclusions. Subjects with a self-reported history of osteoporotic fractures tend to have increased resorption and thinning of the mandibular lower cortex. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;90:518-24)

Eighty-one percent of general dentists and 86 percent of pediatric dentists who are members of the local dental society in Spokane County, Washington, participated in a pilot program to provide dental care in private offices to children up to 5 years of age from low-income families served by the Medicaid program. Outreach staff from the local public health agency recruited and enrolled families in the program. University faculty provided special training in the care of young children to the dentists participating in the program. In the program's first year, 37 percent of the enrolled children had made at least one visit to the dentist, in contrast to 12 percent of children who were not enrolled in the program.

Background Conduct a systematic review and meta-analysis on nonsurgical treatment of patients with chronic periodontitis by means of scaling and root planing (SRP) with or without adjuncts. Methods A panel of experts convened by the American Dental Association Council on Scientific Affairs conducted a search of PubMed (MEDLINE) and Embase for randomized controlled trials of SRP with or without the use of adjuncts with clinical attachment level (CAL) outcomes in trials at least 6 months in duration and published in English through July 2014. The authors assessed individual study bias by using the Cochrane Risk of Bias Tool and conducted meta-analyses to obtain the summary effect estimates and their precision and to assess heterogeneity. The authors used funnel plots and Egger tests to assess publication bias when there were more than 10 studies. The authors used a modified version of the US Preventive Services Task Force methods to assess the overall level of certainty in the evidence. Results The panel included 72 articles on the effectiveness of SRP with or without the following: systemic antimicrobials, a systemic host modulator (subantimicrobial-dose doxycycline), locally delivered antimicrobials (chlorhexidine chips, doxycycline hyclate gel, and minocycline microspheres), and a variety of nonsurgical lasers (photodynamic therapy with a diode laser, a diode laser, neodymium:yttrium-aluminum-garnet lasers, and erbium lasers). Conclusions and Practical Implications With a moderate level of certainty, the panel found approximately a 0.5-millimeter average improvement in CAL with SRP. Combinations of SRP with assorted adjuncts resulted in a range of average CAL improvements between 0.2 and 0.6 mm over SRP alone. The panel judged the following 4 adjunctive therapies as beneficial with a moderate level of certainty: systemic subantimicrobial-dose doxycycline, systemic antimicrobials, chlorhexidine chips, and photodynamic therapy with a diode laser. There was a low level of certainty in the benefits of the other included adjunctive therapies. The panel provides clinical recommendations in the associated clinical practice guideline.

Article Title and Bibliographic Information Safety of oral bisphosphonates: controlled studies on alveolar bone Jeffcoat MK. Int J Oral Maxillofac Implants 2006 May-Jun;21(3):349-53 Level of Evidence 4 Purpose/Question To determine if oral bisphosphonates cause osteonecrosis of the jaw Source of Funding Proctor and Gamble & Merck Research Type of Study/Design 2 cohort studies

Original Article Sedaghatfar M, August MA, Dodson TB. Panoramic radiographic findings as predictors of inferior alveolar nerve exposure following third molar extraction. J Oral Maxillofac Surg 2005;63(1):3-7. Level of Evidence 3 Source of Funding Not reported Type of Study/Design Cross-sectional study

Original Article Longstreth WT Jr, Phillips LE, Drangsholt M, Koepsell TD, Custer BS, Gehrels JA, et al. Dental x-rays and the risk of intracranial meningioma: a population-based case-control study. Cancer 2004;100(5):1026-34. Level of Evidence 3a Purpose The purpose of the study was to investigate whether dental radiography increases the risk for intra-cranial meningioma. Source of Funding National Cancer Insitute Type of Study/Design Population-based case-control study

Original Article Rodu B, Cole P. Smokeless tobacco use and cancer of the upper respiratory tract. Oral Surg Oral Med Oral Path Oral Radiol Endod 2002;93(5):511–5. Level of Evidence 3 Purpose To determine cancer risk of the oral cavity and upper respiratory tract associated with different types of smokeless tobacco Source of Funding Unrestricted gift from the United States Tobacco Company (for more information see http://main.uab.edu/smokersonly/show.asp?durki=63619 ) Type of Study/Design Synthesis of 20 case-control studies and 1 cohort study

Original Article Kressin NR, Boehmer U, Nunn ME, Spiro A, 3rd. Increased preventive practices lead to greater tooth retention. J Dent Res 2003;82(3):223–7. Level of Evidence 3 Purpose To evaluate whether consistent self-report of brushing, flossing, and prophylaxis over a 12-year period is associated with a decreased tooth loss risk both during the 12-year period and during the subsequent follow-up Source of Funding NIH/NIDCR Type of Study/Design Cohort study

Original article Gilbert GH, Shelton BJ, Chavers LS, Bradford EH Jr. Predicting tooth loss during a population-based study: Role of attachment level in the presence of other dental conditions. J Periodontol 2002;73:1427-36. Level of evidence 2b Purpose To investigate whether probing attachment loss is a predictor for tooth loss that is independent of patient, and tooth, factors Source of funding National Institute of Dental and Craniofacial Research Type of study/design Cohort

BACKGROUND: Genetic testing for disease predisposition is rapidly becoming available for a variety of chronic diseases, but it is not clear how the health insurance industry will make reimbursement decisions for these new diagnostics because the long-term clinical and economic benefits are unclear. A provider of dental health benefits requested assistance in assessing a genetic test for a composite interleukin-1 (IL-1) genotype. This test is being marketed to predict risk for progression of periodontal disease. OBJECTIVE: To estimate the incremental clinical and economic outcomes associated with the use of IL-1 testing to identify high-risk patients. METHODS: A disease simulation model was developed using decision-analytic and Markov modeling techniques over a 30-year time frame. RESULTS: In the base-case analysis, using the genetic test resulted in an incremental cost-effectiveness ratio was $32,633 per QALY gained. Sensitivity analysis produced results ranging from increased costs of $300,430 and 3.6 additional cases of severe periodontitis (per one thousand patients) to cost savings of $830,140 and 52.8 fewer cases of severe periodontitis. Sources of uncertainty were 1) patient compliance based on test result, 2) effectiveness of non-surgical therapy, and 3) the relative risk for progression based on genotype. CONCLUSION: The use of genetic testing to guide treatment for periodontitis may result in a wide range of outcomes under different modeling scenarios. These results range from improved patient health and cost-savings to additional costs and poorer health. Economic modeling has identified the additional data required to determine if IL-1 testing can be implemented in a primary care setting in a cost-effective manner. These methods may be used by the health insurance industry to assess the cost-effectiveness of genetic testing for predisposition towards other diseases.

The public does not expect serious side effects when visiting the dentist. And, by and large, the dental profession has succeeded in providing reasonable assurances that serious side effects associated with dental treatments are rare. However they do occur and absolute safety cannot be guaranteed. Even simple and routine dental procedures such as the administration of local anesthetics in dentistry can result in adverse events. Bone or blood products used in periodontal surgery may be contaminated with bloodborne diseases, patients on bisphosphates may develop osteonecrosis of the jaw as a result of surgical procedure, inferior alveolar nerves may get severed with implants or wisdom tooth extractions, and cancers may get induced by computed tomography scans. One can approach such risks from a precautionary or a risk-based perspective. A precautionary approach would consider alternative treatments with lower risks, or inform patients about potential risks even when the risks may only be theoretical and when no credible evidence exists to suggest harm. A risk-based approach, on the contrary, would forego such precautions until credible evidence exists that a procedure or treatment is associated with adverse events. Consider a patient on oral bisphosphonates presenting to your dental practice for dental extractions and implants. The concern is osteonecrosis of the jawVa condition where the jaw necroses. No effective treatment to control this condition exists. The evidence that oral bisphosphonates are associated with this condition is weak. While suggestive evidence on dose-response exists, and while the temporality of the events and the biological plausibility provide suggestions of causality, the evidence is weak. No well-designed case-control studies have established the presence of a causal association. Two contrasting clinical approaches are possible. A precautionary approach would be to provide patients with an informed consent describing in detail the potential risks, to avoid dental surgery, and, if possible, to do a dental clean-up prior to start of bisphosphonates therapy. Such an approach is practiced by some oral and maxillofacial surgeons who provide a detailed informed consent on the risks of bisphosphonates. A risk-based approach would be usual care (no informed consent, no changes in clinical practice). The argument for a risk-based approach would be that the precautionary approach increases cost of care unnecessarily, may cause unnecessary anxiety, and a paralysis of care. A dental practice based on the precautionary principle and the risk-based principle are quite distinct. Three speakers were invited to provide their perspectives on the precautionary principle and their presentations are summarized in the 3 ensuing reports.