Tooth-surface-specific effects of xylitol: randomized trial results.

The Xylitol for Adult Caries Trial was a three-year, double-blind, multi-center, randomized clinical trial that evaluated the effectiveness of xylitol vs. placebo lozenges in the prevention of dental caries in caries-active adults. The purpose of this secondary analysis was to investigate whether xylitol lozenges had a differential effect on cumulative caries increments on different tooth surfaces. Participants (ages 21-80 yrs) with at least one follow-up visit (n = 620) were examined at baseline, 12, 24, and 33 months. Negative binomial and zero-inflated negative binomial regression models were used to estimate incidence rate ratios (IRR) for xylitol's differential effect on cumulative caries increments on root and coronal surfaces and, among coronal surfaces, on smooth (buccal and lingual), occlusal, and proximal surfaces. Participants in the xylitol arm developed 40% fewer root caries lesions (0.23 D2FS/year) than those in the placebo arm (0.38 D2FS/year; IRR = 0.60; 95% CI [0.44, 0.81]; p < .001). There was no statistically significant difference between xylitol and control participants in the incidence of smooth-surface caries (p = .100), occlusal-surface caries (p = .408), or proximal-surface caries (p = .159). Among these caries-active adults, xylitol appears to have a caries-preventive effect on root surfaces (ClinicalTrials.gov NCT00393055).

An assessment of career satisfaction among a group of general dental practitioners in Staffordshire.

OBJECTIVES: To assess the level of job satisfaction among general dental practitioners from one area of England, and to assess the association of various personal and work related factors with job satisfaction. DESIGN: Postal questionnaire survey. SETTING: General dental practices in South Staffordshire, Wolverhampton and Dudley, England. METHOD: An anonymous questionnaire posted to all 396 registered dentists in the above areas. RESULTS: A 75% response rate was achieved. Data were analysed using non-parametric statistics for any significant differences in the scores for stress, respect, overall professional satisfaction, quality of life and overall job satisfaction according to the different demographic groupings of the dentists (alpha =0.05). Dentists with an area of special interest had higher scores in all categories except quality of life. Overall job satisfaction was higher among private dentists, and those in group practices and in non-rural locations. The highest bi-variate correlation occurred between overall job satisfaction and overall professional satisfaction, delivery of care, income, respect and professional time. CONCLUSIONS: Job satisfaction was judged to be good among this group. Stress was the factor associated with the greatest dissatisfaction. This survey produced similar results to preceding US studies, and suggests ways of improving job satisfaction.

A simple method to estimate restoration volume as a possible predictor for tooth fracture.

STATEMENT OF PROBLEM: Many dentists cite the fracture risk posed by a large existing restoration as a primary reason for their decision to place a full-coverage restoration. However, there is poor agreement among dentists as to when restoration placement is necessary because of the inability to make objective measurements of restoration size. PURPOSE: The purpose of this study was to compare a new method to estimate restoration volumes in posterior teeth with analytically determined volumes. MATERIAL AND METHODS: True restoration volume proportion (RVP) was determined for 96 melamine typodont teeth: 24 each of maxillary second premolar, mandibular second premolar, maxillary first molar, and mandibular first molar. Each group of 24 was subdivided into 3 groups to receive an O, MO, or MOD amalgam preparation design. Each preparation design was further subdivided into 4 groups of increasingly larger size. The density of amalgam used was calculated according to ANSI/ADA Specification 1. The teeth were weighed before and after restoration with amalgam. Restoration weight was calculated, and the density of amalgam was used to calculate restoration volume. A liquid pycnometer was used to calculate coronal volume after sectioning the anatomic crown from the root horizontally at the cementoenamel junction. True RVP was calculated by dividing restoration volume by coronal volume. An occlusal photograph and a bitewing radiograph were made of each restored tooth to provide 2 perpendicular views. Each image was digitized, and software was used to measure the percentage of the anatomic crown restored with amalgam. Estimated RVP was calculated by multiplying the percentage of the anatomic crown restored from the 2 views together. Pearson correlation coefficients were used to compare estimated RVP with true RVP. RESULTS: The Pearson correlation coefficient of true RVP with estimated RVP was 0.97 overall (P

Systematic reviews of selected dental caries diagnostic and management methods.

A systematic review of the English-language literature was conducted to address three related questions concerning the diagnosis and management of dental caries: a) the performance (sensitivity, specificity) of currently available diagnostic methods for carious lesions, b) the efficacy of approaches to the management of noncavitated or initial carious lesions, and c) the efficacy of preventive methods among individuals who have experienced or are expected to experience elevated incidence of carious lesions. From 1,328 caries diagnostic and 1,435 caries management reports originally identified, thirty-nine diagnostic studies and twenty-seven management studies were included in the final evidence tables. Point estimates or reasonable range estimates for the diagnostic validity of methods for the diagnosis of carious lesions could not be established from the literature reviewed. There are insufficient numbers of reports of diagnostic performance involving primary teeth, anterior teeth, and root surfaces. For posterior occlusal and proximal surfaces, quality issues and the variation among studies precludes establishing such estimates. The apparent differences in sensitivity among methods are generally smaller than the variation reported within methods. The literature on the management of noncavitated carious lesions consisted of five studies describing seven experimental interventions. Because these interventions varied extensively in terms of management methods tested as well as other study characteristics, no conclusions about the efficacy of these methods were possible. The literature on the management of individuals at elevated risk of carious lesions consisted of twenty-two studies describing twenty-nine experimental interventions. The strength of the evidence for the efficacy of fluoride varnish for prevention of dental caries in high-risk subjects was fair, and the evidence for all other methods was incomplete. Because the evidence for efficacy for some methods, including chlorhexidine, sucrose-free gum, and combined chlorhexidine-fluoride methods, is suggestive but not conclusive, these interventions represent fruitful areas for further research.

Incidence rates for complete cusp fracture.

OBJECTIVES: Although complete cusp fracture is acknowledged to occur frequently, incidence rates have been reported rarely. This study determined incidence rates for complete coronal cusp fracture per person and per tooth type. METHODS: All fractures presenting among enrollees in a dental health maintenance organization using two geographically isolated clinics were noted for 105 days. For a sample of these enrollees, likelihood of attending the clinic in the event of a fracture was assessed through a telephone survey, and the at-risk status of all teeth was determined through a record survey. Incidence rates were calculated for persons, and for individual tooth types for all complete fractures and for non-carious complete fractures. In addition, for posterior teeth the distribution of fractured cusps, and the severity of fractures were examined. RESULTS: Per-person incidence rates for complete coronal fractures for all teeth were 89.0 and 72.7 per 1000 person years, respectively, for all fractures and for non-carious fractures. The rates for all anterior and all posterior teeth were 10.2 and 69.9, respectively, for all non-carious fractures. In mandibular posterior teeth, lingual cusps fractured twice as frequently as facial cusps, while the opposite was true for maxillary premolars. Among maxillary molars, the mesiofacial and distolingual cusps fractured most frequently. The large majority of fractures exposed dentin (95%), while pulpal exposure occurred infrequently (3%). A minority of fractures extended below the gingival crest (24%) or the DEJ (25%). CONCLUSIONS: This is the first report of fracture incidence rates for enumerated persons and teeth at risk and as such helps define the magnitude of the problem for dentists and their patients.

A systematic review of the effectiveness of antifungal drugs for the prevention and treatment of oropharyngeal candidiasis in HIV-positive patients.

OBJECTIVE: A systematic review of randomized clinical trials published between 1966 and April 2000 was undertaken to determine the strength of evidence for the effectiveness of antifungal drugs (nystatin, clotrimazole, amphotericin B, fluconazole, ketoconazole, and itraconazole) to prevent and treat oral candidiasis in human immunodeficiency virus-positive patients. STUDY DESIGN: An automated database search identified 366 articles. Six met inclusion and exclusion criteria with respect to prophylaxis; 12 met criteria for treatment of oral candidiasis. RESULTS: The evidence for the prophylactic efficacy of fluconazole is good, although insufficient to draw conclusions about the other antifungals. Evidence for treatment effectiveness is insufficient for amphotericin B but good for nystatin, clotrimazole, fluconazole, ketoconazole, and itraconazole. CONCLUSION: Suggestions for strengthening the evidence base include the following: use of larger, more well-defined groups; control for immunologic status, viral load, history of oral candidiasis, past exposure to antifungals, baseline oral Candida carriage, drug interactions, and antiretroviral therapy; and consistent use of compliance monitors, fungal speciation, and susceptibility testing.

Ten-year survival rates of teeth adjacent to treated and untreated posterior bounded edentulous spaces.

STATEMENT OF PROBLEM: Failure to replace a single missing posterior tooth may lead to a variety of dental problems, which may ultimately result in tooth loss. However, little is known about the fate of the adjacent teeth if a missing posterior tooth is not replaced. PURPOSE: This retrospective study evaluated the survival of teeth adjacent to treated and untreated posterior bounded edentulous spaces. MATERIAL AND METHODS: Data were obtained from electronic treatment records from the Kaiser Permanente Dental Care Program, Portland, Ore. A final sample of 317 patients who met the study inclusion criteria was identified. Each bounded edentulous space was placed in 1 of 3 treatment categories: untreated, restored with a fixed partial denture, or restored with a removable partial denture. Subsequent treatment and the status of the teeth adjacent to the bounded edentulous space were followed through December 1999. Ten-year Kaplan-Meier survival estimates were generated for each treatment group, and differences in survival were evaluated with the log-rank chi-square test (alpha=.05). RESULTS: There was a significant difference in survival among the 3 treatment categories (P=.005). Spaces restored with a fixed partial denture had longer 10-year survival estimates (92%) than those that remained untreated (81%). Spaces restored with a removable partial denture had the poorest 10-year survival rate (56%). CONCLUSION: Under the conditions and selection bias associated with this retrospective study, the survival of teeth adjacent to a single posterior edentulous space was negatively associated with removable partial denture placement compared with no treatment or the use of a fixed partial denture.

Movement of teeth adjacent to posterior bounded edentulous spaces.

Bounded edentulous spaces (BES)-a missing posterior tooth with intact adjacent teeth-are thought to lead to arch collapse resulting from the movement of adjacent teeth. To determine the rate of change in distance between teeth adjacent to a BES, we examined three successive measurable radiographs of 116 untreated posterior BES cases. The distance between the teeth (DBT) adjacent to the space was measured, and change in DBT (delta DBT) between pre-extraction and follow-up radiographs was calculated. We used linear spline regression to construct models for tooth movement and to identify factors associated with delta DBT. The mean delta DBT was < 1 mm during the first year post-extraction, and the DBT continued to decrease at a successively slower rate each following year. Overall and for each tooth type, the greatest rates of decrease in DBT were seen in the zero to two-year period. In a multivariable model, time since extraction and tooth type were significantly associated with delta DBT. These findings suggest that movement of teeth adjacent to a posterior BES after the first two years is usually gradual and minor within the time frame of this study.

A systematic review of selected caries prevention and management methods.

A systematic review of the periodic scientific literature was undertaken to determine the strength of the evidence for the efficacy of professional caries preventive methods applied to high risk individuals, and the efficacy of professionally applied methods to arrest or reverse non-cavitated carious lesions. An initial search identified 1435 articles, of which 27 were eventually included in the review. Among the 22 studies addressing the prevention of carious lesions in caries-active or high risk individuals, the strength of the evidence was judged to be fair for fluoride varnishes and insufficient for all other methods. Among the seven studies addressing the management of non-cavitated carious lesions, the strength of the evidence for efficacy was judged to be insufficient for all methods. The results do not indicate that the preventive and management methods reviewed are not efficacious; rather, they demonstrate that not enough is known to determine the efficacy of the methods. Suggestions for strengthening the limited evidence base involve the following: i) increasing the number of studies that examine prevention among high risk individuals and non-surgical management of non-cavitated lesions, ii) including a wider variety of subject ages, iii) targeting aspects of the efficacy questions not yet addressed, iv) strengthening research methods employed in the studies, and v) reporting methods and outcomes more completely.

The consequences of not replacing a missing posterior tooth.

BACKGROUND: Failure to replace a missing posterior tooth is assumed to result in host of adverse consequences, which include shifting of teeth and loss of alveolar bone support. METHODS: A retrospective longitudinal study (median follow-up period 6.9 years), using the radiographs of 111 patients who had an untreated bounded edentulous space, or BES, was conducted to determine the extent to which these adverse outcomes occurred. RESULTS: The majority of patients lost 1 millimeter or less of the distance between teeth adjacent to the space, extrusion of the opposing tooth was < or = 1 mm in 99 percent of the cases, and the amount of alveolar bone loss next to the adjacent teeth was < or = 1 mm in 83 percent of the cases. CONCLUSIONS: Within the follow-up time in this study, this group of patients did not exhibit the expected adverse consequences with either the frequency or severity generally assumed to be associated with nonreplacement of a single posterior tooth. CLINICAL IMPLICATIONS: These findings suggest that for the large majority of patients who experience a single-tooth posterior BES, immediate treatment may not be critical to the maintenance of arch stability. Instead, regular follow-up assessments to monitor change in stability and periodontal health may be warranted.

Patients' perception of recovery after third molar surgery.

PURPOSE: This study evaluated patients' perceptions of recovery after third molar surgery. METHODS: Two hundred forty-nine patients (age 13 to 37 years) at 2 clinical centers were enrolled in a prospective study before the surgical removal of third molars. Each patient was given a 21-item Health-Related Quality of Life instrument (HRQOL) to be completed each postoperative day (POD) for 14 days. The instrument was designed to assess patients' perception of recovery: pain, oral function, general activity measures, and other symptoms. Pain dimensions were recorded with a 7-point Likert-type scale; all other conditions were measured on 5-point Likert-type scales. The impact of each predictor variable such as age, gender, and length of surgery on recovery was assessed with Cochran-Mantel-Haenszel statistics, controlling for clinical center. RESULTS: After the 14-day postoperative period, 201 of the original 249 patients returned the completed HRQOL instrument; the 48 patients who did not return their diary had third molar conditions and surgery similar to the 201 patients who responded. On POD 1, 63.5% of patients reported their worst pain as severe (score, 5 to 7/7) at some time during the day. By POD 7, only 15% of patients reported their worst pain as severe. Average pain levels were much less; 29% reported their average pain as severe (score, 5 to 7/7) on POD 1, decreasing to 5.5% by POD 7. Patients experienced substantial interference in oral function; chewing, 85%; mouth opening 78.5%, and speaking 37.5% on POD 1. By POD 6, oral function had improved; chewing, 19%, mouth opening, 15%; and speaking, 1.5%. General measures also were affected on POD 1; social activity, 61.5%; recreation, 70.5%; and daily routine, 60%. Patients assumed a more normal lifestyle by POD 5. Swelling seemed to be at its maximum on PODs 1 and 2 (day 1, 53%; day 2, 61%) and decreased markedly by POD 5 (10%). Food collection in the surgical sites posed the biggest problem for patients on POD 9 (20%). Age was not a predictor of prolonged recovery. However, surgery time 30 minutes or longer, or having all third molars below the occlusal plane, did prolong recovery. Females also reported a longer recovery period. CONCLUSIONS: This information is valuable to patients deciding on third molar surgery and to clinicians providing informed consent.

Development of effectiveness of care and use of services measures for dental care plans.

OBJECTIVES: Standardized measures to assess clinical aspects of the performance of managed dental care plans are not available. This project sought to develop and evaluate measures for effectiveness of care and use of services that could be calculated using a plan's administrative data. METHODS: Two panels of stake holders representing dental plans, purchasers, and dental providers participated in a modified Delphi process to refine initial sets of effectiveness of care and use of services measures modeled after HEDIS measures for medical care. The refined measures were then pilot tested in two dental health maintenance organizations. RESULTS: The development process resulted in specification of seven effectiveness of care measures assessing disease activity classification, and prevention and outcomes for caries, periodontal disease, and tooth loss. Six use of services measures focusing on prophylaxes, third molar surgery, preventive, restorative, prosthetic, surgical, and endodontic care also were specified. Pilot testing of the measures indicated reasonable reliability and sensitivity, but also demonstrated the need for supervision or auditing of the process. CONCLUSIONS: These standardized measures for dental care plan performance are available for immediate use. However, because the measures depend on diagnostic information (periodontal probing data and diagnoses associated with restorative treatments) in the administrative data set, their adoption will require changes in most plans' data systems and data collection policies.

Evaluation of audit-based performance measures for dental care plans.

OBJECTIVES: Although a set of clinical performance measures, i.e., a report card for dental plans, has been designed for use with administrative data, most plans do not have administrative data systems containing the data needed to calculate the measures. Therefore, we evaluated the use of a set of proxy clinical performance measures calculated from data obtained through chart audits. METHODS: Chart audits were conducted in seven dental programs--three public health clinics, two dental health maintenance organizations (DHMO), and two preferred provider organizations (PPO). In all instances audits were completed by clinical staff who had been trained using telephone consultation and a self-instructional audit manual. The performance measures were calculated for the seven programs, audit reliability was assessed in four programs, and for one program the audit-based proxy measures were compared to the measures calculated using administrative data. RESULTS: The audit-based measures were sensitive to known differences in program performance. The chart audit procedures yielded reasonably reliable data. However, missing data in patient charts rendered the calculation of some measures problematic--namely, caries and periodontal disease assessment and experience. Agreement between administrative and audit-based measures was good for most, but not all, measures in one program. CONCLUSIONS: The audit-based proxy measures represent a complex but feasible approach to the calculation of performance measures for those programs lacking robust administrative data systems. However, until charts contain more complete diagnostic information (i.e., periodontal charting and diagnostic codes or reason-for-treatment codes), accurate determination of these aspects of clinical performance will be difficult.

Dentist reliability in classifying disease risk and reason for treatment.

OBJECTIVES: The reliability of practicing dentists' classifications of patients' caries risk and periodontal disease risk and reason for treatment for individual teeth were determined. The risk classification protocols had been in use in a group practice for more than a year, and the reason-for-treatment protocol had been introduced six months previously. METHODS: Eight dentists' classifications for caries (n = 66) and periodontal disease risk (n = 66), and six dentists' classifications for reason for treatment (n = 73) were compared to those of a nominal standard examiner. Reliability was expressed as percent agreement and kappa values. RESULTS: Percent agreement was 76 percent, 83 percent, and 74 percent for caries, periodontal disease, and reason for treatment, respectively, with kappa values of 0.56, 0.70, and 0.69. CONCLUSIONS: Dentists can attain reasonable levels of reliability using simple classification protocols with little formal training, although misclassification may be problematic for specific administrative or research-related purposes.

Survival rates of teeth adjacent to treated and untreated posterior bounded edentulous spaces.

It is widely assumed that if posterior bounded edentulous spaces, or BESs, are not treated, the adjacent teeth ultimately will be lost. The authors examined this assumption by determining the survival of teeth adjoining 569 treated and untreated BESs. In the short term, the assumption was not supported. The great majority of untreated BESs did not result in loss of an adjacent tooth. Treatment with a removable partial denture did not increase the likelihood of adjacent tooth survival, while treatment with a fixed partial denture did result in modestly improved survival of adjacent teeth.

Meta-analysis of fixed partial denture survival: prostheses and abutments.

STATEMENT OF PROBLEM: Few estimates of the probability of various outcomes associated with replacement of missing teeth with fixed partial dentures have been reported. Existing longitudinal studies have reported widely disparate results for the survival of fixed partial dentures, but these studies have used different definitions of failure and varying periods of follow-up. PURPOSE: This study used meta-analysis to formulate annual probability estimates for three categories of fixed partial denture or abutment survival. METHODS: A systematic review of the English language literature since 1960 identified eight studies that met the preset inclusion criteria. Estimated annual survival proportions were back-calculated based on the Kaplan-Meier model and these proportions were combined through a fixed effects model meta-analysis. The probabilities and corresponding 95% confidence intervals at 5, 10, and 15 years for the three categories of survival are reported. RESULTS: For the aggregate population represented by the limited longitudinal studies available, this meta-analysis indicated that less than 15% of fixed partial dentures were removed or in need of replacement at 10 years; whereas, nearly one third were removed or in need of replacement at 15 years. Less than 5% of abutments were removed at 10 years.

Descriptive models of restorative treatment decisions.

OBJECTIVES: This study developed descriptive models of dentists' restorative treatment decisions for individual teeth. Such models could be useful in personnel planning, in assessing the effects of dental treatment programs, and in furthering understanding of dentists' decision-making processes. METHODS: Logistic regression was used to construct models of the probability of individual teeth receiving a recommendation for restorative treatment. Independent variables for the models were data from epidemiologic oral examinations and self-administered questionnaires of subjects who were seeking treatment at a dental school. Data for the dependent variable, the probability of treatment, were collected from multiple dentists' treatment plans of these subjects. Separate models were constructed for molar, premolar, and anterior teeth. An assessment of the models' utilities in a different population consisted of comparing the treatment probabilities estimated by the models with those actually experienced by a community sample of 317 individuals who visited dentists in the 18 months following our examination. RESULTS: Constructed models for molar, premolar, and anterior teeth returned kappa values of 0.60, 0.62, and 0.65, respectively, for the original data set. The models were less accurate in identifying which teeth received treatment among subjects in the community sample, with kappas of 0.10, 0.18, and 0.20, respectively. CONCLUSIONS: Models of dentists' restorative treatment decision making based on clinical and nonclinical data can determine the probability of treatment for individual teeth with reasonable accuracy. Hence, the approach holds promise for developing measures of normative treatment need. However, the models are not accurate predictors of dichotomous decisions by individual dentists regarding treatment interventions. Both differences in the subject samples used to develop and assess the models and individual dentist idiosyncrasies may contribute to this inaccuracy.