Showing papers in "Evidence-based Dentistry in 2005"

Study design I

Abstract: This is the first of a series of articles that will describe the different types of study design; considerations when choosing a study design; and the advantages and disadvantages of each type of study. This first article explains the importance of choosing an appropriate design and the decisions to be made when doing so.

Longer orthodontic treatment may result in greater external apical root resorption.

Abstract: Data sources Medline was the primary data source, with references of identified papers then being reviewed for additional studies. Study selection Studies were included if they were clinical trials, in English, of samples of greater than 10 subjects who had undergone fixed appliance orthodontic treatment and who had both pre- and postoperative X-rays available. A measurement of external apical root resorption (EARR) in maxillary incisors was essential as was a measure of displacement with the apex of the root as reference. Data extraction and synthesis Variables were coded and articles graded by three independent investigators who subsequently negotiated final coding and assessed the methodological soundness of each study. A cumulative 'meta-analysis factor' was computed for each article. Articles were evaluated on study design; population sample; treatment assignment; documentation of statistics; the accuracy of root resorption measurement and apical displacement of incisor roots. A funnel plot analysis did not identify publication bias. Results Eight articles were included in the statistical analysis. Two did not contain data for mean apical displacement and therefore correlations between mean EARR and mean apical displacement could not be calculated for them. The mean meta-analysis factor was 39 (range, 12-78). Mean root resorption was 1.421+/-0.448 mm (n=8), and mean apical displacement was 2.382+/-0.756 mm. The weighted correlation coefficient between mean root resorption and apical displacement was 0.822 and that between mean root resorption and treatment duration was 0.852. Conclusions This analysis suggests that treatment-related root resorption is correlated with the distance the apex moves and the length of time the treatment took.

Delay and failure to publish dental research.

Abstract: To investigate the incidence and time taken to full publication of abstracts presented at dental scientific meetings. A retrospective observational study. All abstracts from the 1993 proceedings of the European Orthodontic Society (EOS) and European Organisation for Caries Research (ORCA) and a 10% random sample of abstracts from the International Association for Dental Research (IADR) conferences. A cross-referenced Medline search of abstract title and authors was undertaken to determine whether abstracts had been published as full papers. Searches were censored 1 year prior to and 5 years post publication as an abstract. Publication rate was compared between abstracts presented orally and as posters. Publication as a full paper and time taken to publication. 546 abstracts were investigated. 252 abstracts (46.1%) were found as full reports. Median time to publication of all abstracts was 18 months (IQR 9, 30 months). 99 of the oral abstracts (57%) and 153 (41%) of the poster abstracts were published. Relative Risk Oral vs Poster=1.37 CI (1.19, 1.55). More than half of the research presented at EOS, IADR and ORCA in 1993 remained unpublished 5 years after presentation at the conference. Oral presentations were published more frequently than poster presentations.

No benefit from prophylactic antibiotics in third molar surgery.

Abstract: DESIGN This was a randomised controlled trial in a hospital environment. INTERVENTION After surgical removal of third molars postoperative treatment was with oral amoxicillin-clavulanic acid (AC) or clindamycin (CL) or no antibiotics (C). The surgical technique was the same in all cases, and the follow-up period was 4 weeks. OUTCOME MEASURE Parameters evaluated were pain, differences in mouth opening, infection, the occurrence of dry socket, and adverse postoperative side effects. RESULTS A total of 528 lower third molars were surgically removed in 288 patients during a period of 30 months. The patients' mean age was 20.7 years (age range, 14-61 years). No severe complications such as perimandibular abscess or cellulitis occurred in any patient in any group. There was no significant difference between the groups in the overall occurrence of local infection symptoms after surgery (range, 3.4-4.4%; mean, 3.98%), nor for other parameters. Interestingly, 69.6% of the patients with dry sockets had partially erupted third molars. This rate was the same in each group (62.5% versus 75%) and did not vary significantly. Reported adverse effects were similar in each group (15.3% for AC, 12.2% for CL, 13.9% for C). CONCLUSIONS The results show that specific postoperative oral prophylactic antibiotic treatment after the removal of lower third molars does not contribute to better wound healing, less pain nor increased mouth opening, and could not prevent the cases of inflammatory problems after surgery, respectively. It is therefore not recommended for routine use.

Strong evidence that daily use of fluoride toothpaste prevents caries.

Abstract: Medline, Cochrane Library, reference lists of identified articles and selected textbooks were used to source studies. Selected studies were randomized or controlled clinical trials of at least 2 years’ duration with caries increment in the permanent (DMFS/T) or primary (dmfs/t) dentition as the endpoint. Reports published in Danish, English, French, German, Italian, Norwegian, Spanish or Swedish were included. For multiply reported trials the one with the longest follow-up period was included. Inclusion decisions and grading of the studies was performed independently by two of the authors. The main outcome was prevented fraction (PF). A pooled estimate was calculated for included studies. Fifty-four studies were included. There was strong evidence for a caries-preventive effect of daily use of fluoride toothpaste compared with placebo in the young permanent dentition (PF, 24.9%; standard deviation, ±11.5%). Toothpastes containing 1500 ppm of fluoride had a superior preventive effect (additional PF, 9.7%; range 0–22%) compared with standard dentifrices of 1000 ppm fluoride. There was also strong evidence for higher caries reductions with supervised toothbrushing compared with unsupervised brushing. There was incomplete evidence regarding the effect of fluoride toothpaste in the primary dentition. This review reinforces the importance of daily toothbrushing with fluoridated toothpastes for preventing dental caries, although long-term studies in age groups other than children and adolescents are still lacking.

Outcomes, what outcomes?

Abstract: One of the first stages of the evidencebased approach is to formulate a clinical question. The standard way to do this is by using the well-established PICO (problem, intervention, comparison, outcome) format, as described by Richardson et al. This approach is also taken to define the problem in systematic reviews because poorly focused questions lead to unclear decisions about what research to include and how to summarise it. Regular readers will be aware that many of the systematic review summaries that we publish in Evidence-based Dentistry find that the available evidence is not strong enough to answer the questions posed by the reviewers. One of the strengths of a well-conducted systematic review, the identification of all the available literature on a topic, can be one of its frustrations because the quality of the studies is not strong enough to answer the question posed without bias. Consequently, it tells us not only how little we do know but how much we do not know. As well as the frequent problems with the quality of study-design or of reporting, which both cause difficulty when conducting a systematic review, there is a further difficulty. This is related to the outcome or outcome measures used (a good classification of the types of outcomes available is given by Bader and Ismail). For example, there are a large number of indices for expressing tooth decay and periodontal disease, or potential outcomes in temporomandibular disorders. This causes problems when conducting meta-analyses. Sutherland and Matthews have discussed the issues caused by this, highlighting some of the lessons learned while preparing systematic reviews for clinical guidelines. Hujoel has also argued that the ‘‘lack of a rigorous scientific basis for the measurement of periodontitis has led to changing opinions as to what measures should be used to assess periodontal treatment efficacy and how to interpret changes’’. Hujoel highlights too the difference between true end points, which are tangible to the patients and directly measure how a patient feels, functions or survives (eg, tooth loss or pain or oral health-related quality-of-life measurements), and surrogate end points: the latter are intangible to the patient, such as changes in probing attachment level or gingival crevicular fluid level. In dentistry our focus tends to be on surrogate end points or outcomes although there is an increasing focus on oral health-related quality of life measures. Hujoel does support the use of surrogate end points when two conditions are met, however: K Informativeness: is there evidence that the surrogate predicts the true end point? K Specificity: is the treatment effect on the true endpoint mediated through the surrogate end point? Although the focus of Hujoel’s paper is periodontal disease, many of his arguments are just as relevant to other fields of dental research. In the field of dental caries, work has started on the development of ‘‘ICDAS’’: an international system for caries detection and assessment. The aim of ICDAS is to facilitate caries epidemiology, research and appropriate clinical management. This has the potential to help greatly when combining studies on dental caries into a meta-analysis in the future. There is the scope for similar developments in other fields within dentistry. There is the opportunity for organisations such as the International Association for Dental Research and the World Dental Federation, along with specialist associations, to lead the way to a greater consistency in the outcomes we measure in dentistry. Without this uniformity we are not making the most of the original research that is being carried out and we may not realise the full potential of results combined into systematic reviews.

Risk-based recall intervals recommended

Abstract: This summary of clinical guideline 19 from NICE includes recommendations for patients of all ages (both dentate and edentulous patients) and covers primary care received from NHS dental staff (dentists, independent contractors contracting within the NHS, dental hygienists and therapists) practising in England and Wales. The guideline takes into account the potential of the patient and the dental team to improve or maintain the quality of life and to reduce morbidity associated with oral and dental disease. The guideline does not cover intervals between dental examinations that are not routine dental recalls; that is, intervals between examinations related to ongoing courses of treatment, or part of current dental interventions, nor does it cover emergency dental interventions, or intervals between episodes of specialist care.

Multiple idiopathic cervical root resorption most frequently seen in younger females.

Abstract: Medline and references of included studies were used to source articles. Selected articles were case reports or reviews of patients who had multiple root resorption with no systemic or local factors that may have contributed to root resorption, the resorption originating at the cemento-enamel junction of teeth and involving more than three teeth in the dentition. Clinical, histological and historical findings are summarised for all identified patients. Multiple idiopathic cervical root resorption (MICRR) was an incidental finding on routine clinical and radiographic examination. There appeared to be no correlation between this type of resorption and any medical or dental finding. Radiographically, MICRR was found to begin at the cemento-enamel junction and then either progress to involve the entire cervical region or, at some point, spontaneously arrest. Those cases that progressed to involve the entire cervical region required extraction. The number of teeth that demonstrated this condition ranged from five up to 24 per patient. More teeth became involved as the condition was followed in time. There was no detectable frequency of occurrence for any particular dental region or tooth among the involved teeth. Of a total of 18 patients, 13 were females whose ages ranged from 7 to 68 years of age. Ten of the 18 patients were Caucasian. Multiple idiopathic cervical root resorption was found most frequently associated with younger females. This condition appeared to be of unknown aetiology and uncertain natural history.

Study design II. Issues of chance, bias, confounding and contamination.

Abstract: In the first article in the series I explained the importance of study design and gave an overview of the main types of design Here, I describe the ways in which the results of a study may deviate from the truth and the measures that can be taken to help minimise this when designing a study

The eyes have it. How good is DIAGNOdent at detecting caries

Abstract: Medline (1999–June 2004) provided the primary data source with references from one paper being reviewed for additional studies. The authors of one article were contacted for additional details. Articles, in English that assessed a commercially available caries detection device the DIAGNOdent (KaVo Dental GmbH Biberach), used human teeth with and without caries, and expressed diagnostic performance in terms of sensitivity and specificity of caries detection against a histological gold standard were included. Data were extracted to determine whether articles included: an appropriate study population; an adequate description of the test; an appropriate reference standard; a blinded comparison of test and reference samples and avoidance of verification bias. No quality score was assigned. Of the 25 studies identified, 16 assessed the in vitro performance of DIAGNOdent (DD) on occlusal surfaces of primary and permanent posterior teeth, four reported similar in vivo assessments, two examined DD performance on smooth surfaces and the final three addressed detection of secondary caries and residual caries in simulated cavities. DD sensitivity scores for in vitro detection of occlusal dentinal caries ranged from 0.19 to 1.0 (n=16) with 14 of the 16 results being ≥0.73. Specificity values ranged from 0.52 to 1.00. DD tended to show higher sensitivity but lower specificity than visual assessment methods. Only four studies considered DD in vivo performance and demonstrated sensitivity from 0.73 to 0.96 and specificity from 0.63 to 0.95. In the limited studies available DD demonstrated greater sensitivity but poorer specificity than visual caries diagnosis. Combined with the fact that little in vivo evidence is available for DD performance, the greater number of false-positive diagnoses suggest it should not be relied on as a clinician's primary diagnostic method.

Insufficient evidence to support or refute the need for 6-monthly dental check-ups. What is the optimal recall frequency between dental checks?

Abstract: DATA SOURCES: Trials were sourced using the Cochrane Oral Health Group Trials Register, the Cochrane Central Register of Controlled Trials, Medline and Embase. Reference lists from relevant articles were scanned and the authors of some papers were contacted to identify further trials and obtain additional information. STUDY SELECTION: Trials were selected if they met the following criteria:design: random allocation of participants;participants: all children and adults receiving dental check-ups in primary-care settings, irrespective of their level of risk for oral disease;interventions: recall intervals for either clinical examination only, clinical examination plus scale and polish, clinical examination plus preventive advice, clinical examination plus scale and polish plus preventive advice, no recall interval/patient-driven attendance (which may be symptomatic), or clinician risk-based recall intervals;outcomes: clinical status outcomes for dental caries including, but not limited to, mean dmft/DMFT, dmfs/DMFS scores, caries increment, filled teeth (including replacement restorations), early carious lesions (arrested or reversed); periodontal disease (including, but not limited to, plaque, calculus, gingivitis, periodontitis, change in probing depth, and attachment level); oral mucosa (presence or absence of mucosal lesions, potentially malignant lesions, cancerous lesions, and size and stage of cancerous lesions at diagnosis).In addition, the following outcomes were considered where reported: patient-centred outcomes, economic-cost outcomes, other outcomes such as improvements in oral health knowledge and attitudes, harms, changes in dietary habits, and any other oral health-related behavioural change. DATA EXTRACTION AND SYNTHESIS: Information regarding methods, participants, interventions, outcome measures, and results were independently extracted, in duplicate, by two authors. Authors were contacted, where deemed necessary and where possible, for further details regarding study design and for data clarification. A quality assessment of the included trial was carried out. The Cochrane Oral Health Group's statistical guidelines were followed. RESULTS: Only one study (with 188 participants) was included in this review and was assessed as having a high risk of bias. This study provided limited data for dental caries outcomes (dmfs/DMFS increment) and economic cost outcomes (reported time taken to provide examinations and treatment). CONCLUSIONS: There is insufficient evidence from randomised controlled trials (RCT) to draw any conclusions regarding the potential beneficial and harmful effects of altering the recall interval between dental check-ups. There is insufficient evidence to support or refute the practice of encouraging patients to attend for dental check-ups at 6-monthly intervals. It is important that high quality RCT are conducted for the outcomes listed in this review in order to address its objectives.

Oral health promotion reduces plaque and gingival bleeding in the short term.

Abstract: Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Health Technology Assessment Database, UK National Health Service Economic Evaluation Database, Cochrane Central Register of Controlled Trials and Medline. There were no date limits or language restriction. Systematic reviews and controlled trials (randomised or quasi-randomised) assessing reductions in dental plaque levels and/or gingival bleeding (gingivitis) and comparing health education/health promotion interventions that did not involve clinical professional input or the use of pharmacological interventions, such as antiplaque agents were included. Studies involving only special groups, such as orthodontic or medically compromised patients or assessing only denture plaque, were excluded. A range of data were extracted from systematic reviews and trials, quality assessment was undertaken, and a qualitative overview of the findings was provided. Twenty-six potentially relevant studies were identified. Six reports of five systematic reviews and 13 trials were discussed: four studies were not assessed as one was published in Polish and three could not be located. A wide range of educational and behavioural interventions were considered. These did not generally include clinical interventions and social or environmental approaches. The reviews have a number of limitations so their conclusions should be viewed with a degree of caution. However, the majority of studies achieved short-term reductions in plaque and gingival bleeding. Precise estimates of the improvement are difficult to assess because of the range and diversity of outcome measures used. The results of two meta-analyses indicate a reduction in plaque levels of 32–37%. Of 13 recently published trials evaluating educational interventions, five were set in schools, four focused on adults either in a clinical or workplace setting, three targeted older people, and one, infants. The design quality of the trials was variable. Allocation concealment was clearly described in two trials only, but blind outcome assessment was described in most of the trials and so were dropout rates. Other problems included a lack of controls, use of single blinding and relatively short follow-up. Positive effects on plaque and/or bleeding outcomes were seen in eight studies with no difference in five studies, of which only two employed a control group. Nevertheless, for the two trials that compared various approaches, reductions in plaque and gingival bleeding were generally observed in all groups over the trial period. None of the studies produced a negative effect. Although all the studies evaluated educational interventions, there was no clear indication that any particular type or style of educational approach was more effective than any other. Reductions in plaque and gingival bleeding were seen in the short term in the majority of studies reviewed. The clinical and public health significance of these changes is, however, questionable. Future studies should use longer follow-up periods to assess whether short-term beneficial changes are sustained. Other forms of oral health promotion require better quality evaluation if they are to be used to improve periodontal health.

Better success rate for root canal therapy when treatment includes obturation short of the apex.

Abstract: Better success rate for root canal therapy when treatment includes obturation short of the apex

Smokers have less reductions in probing depth than non-smokers following nonsurgical periodontal therapy.

Abstract: Smokers have less reductions in probing depth than non-smokers following nonsurgical periodontal therapy

Triclosan-containing toothpastes reduce plaque and gingivitis.

Abstract: Data sources Sources of studies were the Cochrane Controlled Trials Register, Medline and Embase. Personal files and the reference lists of all articles were checked for further studies. Study selection Trials were selected if they met the following criteria: there had been random allocation of participants; participants were adults with plaque and gingivitis; there was unsupervised use of dentifrices for at least 6 months; and primary outcomes were plaque and gingivitis after 6 months. Data extraction and synthesis Data were extracted by two reviewers independently. For each plaque and gingivitis index, the mean differences for each study were pooled as weighted mean differences (WMD) with the appropriate 95% confidence intervals (CI) using the random effects model. Results Sixteen trials provided data for the meta-analysis. The triclosan/copolymer dentifrice significantly improved plaque control compared with a fluoride dentifrice, with a WMD of -0.48 (95% CI, -0.64 to -0.32) for the Quigley-Hein index and WMD of-0.15 (95% CI,-0.20 to -0.09) for the plaque severity index. When compared with a fluoride dentifrice, the triclosan/copolymer dentifrice significantly reduced gingivitis with WMD of -0.26 (95% CI, -0.34 to -0.18) and -0.12 (95% CI, -0.17 to -0.08) for the Loe and Silness index and for gingivitis. Conclusions This systematic review indicates that a dentifrice that contains triclosan/copolymer provides a more effective level of plaque control and periodontal health than a conventional fluoride dentifrice.

Dental procedures can be undertaken without alteration of oral anticoagulant regimen

Abstract: Data sources Medline provided the primary data source with references from identified articles being reviewed for additional studies. The Cochrane Collaboration database was also searched and a search performed of cited references. Study selection Clinical studies, in English, examining perioperative management of patients receiving long-term oral anticoagulant (OAC) therapy were selected. Data extraction and synthesis Data were extracted regarding management strategy, thrombo-embolic events and bleeding complications, and type of surgical or invasive procedure. Event rates were reported as number of patients experiencing the event divided by number of patients at risk. Binomial and Poisson distributions were used to calculate 95% confidence intervals (CI). Results A total of 31 reports were identified and concluded to be of generally poor quality. For studies reporting thrombo-embolic events, 29 events occurred in 1868 patients (1.6%; 95% CI, 1.0-2.1) of which seven were strokes (0.4%; 95% CI, 0.0-0.7). Major bleeding while receiving OAC was reported to be rare for dental procedures (occurring in four out of 2014 individuals), arthrocentesis (in none out of 32), cataract surgery (none out of 203), and upper endoscopy or colonoscopy with or without biopsy (no occurrences in 111 patients). For the other invasive and surgical procedures reviewed, OAC needs to be withheld and a suitable personalised perioperative management strategy instigated. A guideline, based on the limited evidence available, for the perioperative management of anticoagulation for procedures requiring discontinuation of OAC is presented. Conclusions Certain surgical or invasive procedures can be undertaken in patients who are taking OAC therapy without alteration of their regimen. For procedures requiring discontinuation of OAC, personalised management strategies are required. More rigorous studies are needed to better inform this debate.

Atraumatic restorative techniques could reduce discomfort in children receiving dental treatment.

Abstract: Atraumatic restorative techniques could reduce discomfort in children receiving dental treatment

Bidi smokers at increased risk of oral cancer

Abstract: DATA SOURCES Source articles were searched for using Medline, the Cochrane Library and within the references lists of identified articles. STUDY SELECTION Articles were selected that included data enabling construction of 2 x 2 tables to estimate odds ratios (OR) and 95% confidence intervals (CI). DATA EXTRACTION AND SYNTHESIS For each study, two-way contingency tables were constructed, based on exposure frequency distributions, for cases and controls. Unadjusted OR and 95% CI were recalculated based on the reported data using standard procedures. Separate contingency tables were made for bidi smoking, cigarette smoking and both types of smoking if the data were available in the same article. The overall OR combined across all studies, and its 95% CI, was calculated using a random-effects model for bidi and cigarette smoking. Tests for publication bias and heterogeneity were conducted. Confounding factors, for example, betel quid chewing or alcohol use, were not included in the meta-regression model. RESULTS An increased risk of oral cancer was found for bidi smokers compared with people who had never smoked (OR, 3.1; 95% CI, 2.0-5.0) whereas no significant pattern of risk was found for cigarette smokers (OR, 1.1; 95% CI, 0.7-1.8). There was substantial heterogeneity in the pooled OR estimate. CONCLUSIONS The results clearly indicate that bidi smokers are at increased risk of oral cancer. It is important that this information be incorporated into smoking prevention and cessation efforts, particularly in the urban poor and rural mass in south Asian countries where bidi smoking is widespread.

Oral lycopene — an efficacious treatment for oral leukoplakia?

Abstract: DESIGN: This was a randomised controlled trial (RCT) of the treatment of oral leukoplakia with the carotenoid lycopene INTERVENTION: A total of 58 patients received either 8 mg oral lycopene in two doses daily (n=20), 4 mg oral lycopene in two doses daily (n=18) or placebo capsules (n=18), for a 3-month period Progress of patients was followed for a further 2 months OUTCOME MEASURES: An objective clinical response, evaluated by bidimensional measurement of the lesion and colour photography, was classified as complete, partial, stable or progression Histological status was categorised and ranked as normal (0), atypical hyperplasia (1), mild dysplasia (2), moderate dysplasia (3) or severe dysplasia (4) Histological response was then described by the change in rank, for example, from moderate dysplasia (3) to atypical hyperplasia (1) would indicate an improvement of 2 units RESULTS: There was no significant difference in the clinical response of people who took 8 mg lycopene compared with those taking 4 mg lycopene The clinical responses measured in both these groups were significantly greater, however, than those in the control group (P<001) The response, assessed histologically, after the 8-mg lycopene treatment was significantly better than that from 4 mg lycopene (P<005) and than the response seen in the control group (P<0001) Patients taking 4 mg lycopene also responded significantly better than those in the control group (P<005) CONCLUSIONS: Oral lycopene appears, from this small RCT conducted over 5 months, to be effective in the treatment and management of oral leukoplakia

Maternal smoking during pregnancy is associated with a higher risk of non-syndromic orofacial clefts in infants

Abstract: Maternal smoking during pregnancy is associated with a higher risk of non-syndromic orofacial clefts in infants

More women in Europe and Australia have dental agenesis than their counterparts in North America.

Abstract: More women in Europe and Australia have dental agenesis than their counterparts in North America

Leukoplakia prevalence estimate lower than expected

Abstract: Data were sourced using Medline and Embase. Initial selection criteria were that study samples should be representative of the underlying adult population and that the leukoplakia diagnostic criteria used by the examiners should have been widely accepted ones. Because most published studies did not comply with these requisites, modified criteria were as follows. First, the sample, even if not representative of the underlying study population, should not have been collected from surgical departments of dental hospitals or clinics, where leukoplakia is usually treated (these studies would overestimate the disease prevalence). Secondly, even if the examiners were not calibrated, the diagnostic criteria used should be consistent with the internationally accepted criteria and must have been reported in the text. Thirdly, to make statistical analysis possible even if leukoplakia prevalence was not reported as a proportion, the overall number of sampled subjects and the number with the condition must be easy to extrapolate with a high level of accuracy. Data were pooled using inverse variance weighting and random-effect methods. A sensitivity analysis was performed. A total of 23 primary studies was included, giving point-prevalence estimates with the inverse variance method of 1.49% [95% confidence interval (CI), 1.42–1.56] and 2.60% (95% CI, 1.72–2.74) with the random-effects method. The high between-study heterogeneity and the sensitivity analyses suggested that the second estimate was more reliable. Leukoplakia was significantly more prevalent in males (prevalence ratio, 3.22), but no difference was found between geographical areas and between younger and older adults. Using these data, the crude annual oral cancer incidence rate attributable to leukoplakia would be between 6.2 and 29.1 cases per 100 000 people. The pooled leukoplakia prevalence estimate was lower than expected. The estimated oral cancer incidence rate due to leukoplakia malignant transformation was high, however, and suggested that the global number of oral cancer cases is probably under-reported, particularly in developing countries.

90% of fixed partial dentures survive 5 years. How long do conventional fixed partial dentures (FPDs) survive and how frequently do complications occur?

Abstract: PubMed (1966–April 2004) provided the primary data source along with the bibliographies from identified articles and reviews. As there were no randomised controlled trials, English language prospective and retrospective cohort studies were selected if they had a mean follow-up of ≥5 years, included patients who were clinically examined at follow-up, reported details on suprastructures and described at least one-third of reconstructions as fixed partial dentures (FPDs). Two independent reviewers screened articles for inclusion. Disagreements were resolved by discussion and agreement determined by kappa. Three reviewers extracted data on the survival and success of the reconstructions and on biological and technical complications. Studies deemed sufficiently similar by design were pooled using negative binomial regression with robust standard errors. Ten-year survival risks were calculated using exp(−10 × failure rate) and 10-year failure risks using 1–S(10). 17 retrospective and two prospective cohort studies including 1764 patients with 3548 FPDs analyzed in total. Meta-analysis was undertaken and after exclusion of one outlier a 10-year FPD survival of 92% was estimated. Only four studies provided information on FPD success — pooled complication rate was 34.1/1000 FPD years (95% CI 16–74). Exclusion of one outlier resulted in an estimated 10-year success of 81.1%. Considering biological complications, the estimated 10-years risk for caries at abutments was 9.5% (95% CI 4.6–89.9) while that for FPD loss due to caries and periodontal disease were 2.6% (95% CI 1.6–4.2) and 0.5% (95% CI 0.1–2.2), respectively. Estimated 10-year risks for technical complications were: 6.4% (95% CI 3.9–10.4) for loss of retention; 2.1% (95% CI 1.4–3.2) for loss of FPD due to abutment fracture and 3.2% (95% CI 1.5–6.5) for material fractures. Estimated success and survival rates for conventional FPDs largely confirm those of previous reviews. Technical complications such as loss of retention, which have not been reviewed before, resulted in a greater risk of FPD loss than did biological complications.

Ten-year survival rate for cantilevered fixed partial dentures.

Abstract: DATA SOURCES PubMed (1966-April 2004) provided the primary data source along with the bibliographies from identified articles and reviews. A manual search of two relevant journals (Clinical Implant Dentistry and Related Research, Clinical Oral Implants Research, International Journal of Oral & Maxillofacial Implants, International Journal of Periodontics and Restorative Dentistry, International Journal of Prosthodontics, Journal of Clinical Periodontology, Journal of Periodontology and Journal of Prosthetic Dentistry published; published 2001-2003) provided a further source of data. STUDY SELECTION Because there were no randomised controlled trials (RCT) that compared fixed partial dentures (FPD) with and without cantilever extensions, other studies were selected if they met the following criteria: were published in the English language; were prospective and retrospective cohort studies; had a mean follow-up of >5 years; included patients who were clinically examined at follow-up; and reported details on suprastructures and described at least one-third of reconstructions as FPD. DATA EXTRACTION AND SYNTHESIS Two independent reviewers screened articles for inclusion. Disagreements were resolved by discussion and agreement determined by kappa. Two reviewers extracted data on the survival and success of the reconstructions and on biological and technical complications. Failure and complication rates were calculated by dividing the number of events by the total exposure time. RESULTS Three prospective and 10 retrospective cohort studies incorporating 700 patients and 816 FPD were included. The mean number of cantilever extensions ranged from 1.1 to 6.0. Meta-analyses gave an estimated survival, after 10 years, of 81.8% [95% confidence interval (CI), 78.2-84.9] and a proportion success of 63% (95% CI, 54.7-70.2). Considering biological complications using Poisson model analyses, the estimated rate of FPD lost because of caries after 10 years was 3.1% (95%CI, 1.0-8.8) and that for loss of vitality was 32.6% (95% CI, 13.9-64.9). The rate of FPD lost because of periodontitis was 1% (95% CI, 0.3-3.0). Cumulative 10-year complication rates were: 2.9% (95% CI, 1.7-5.0) for fracture of abutment tooth; 2.4% (95% CI, 0.6-9.8) for rate of loss as a result of abutment fracture; 16.1% (95% CI, 8.8-28.4) for loss of retention; and 5.9% (95% CI, 3.3-10.4) for material complications. CONCLUSIONS Success and survival rates for cantilever FPD are poorer than those for conventional FPD and this is accompanied by frequent biological and technical complications.

Alcohol consumption and the risk for disease. Is there a dose-risk relationship between alcohol and disease?

Abstract: Top of pageAbstract Data sources Searches for studies were made using MEDLINE, Current Contents, EMbase, CAB Abstracts and Core Biomedical Collection, and the reference lists of selected articles. A search was also made by hand of relevant journals. Study selection Studies were included if they met the following criteria: (i) case–control or cohort study published as an original article; (ii) findings expressed as odds ratio or relative risk (RR) considering at least three levels of alcohol consumption; (iii) papers reported the number of cases and controls and the estimates of the odds ratios or RR for each exposure level. When the results of a study were published more than once, only the most recent and complete article was included in the analysis. Data extraction and synthesis Two readers, blinded to the authors' names and affiliations and to the results pertaining to alcohol consumption, independently determined the eligibility and scored the quality of the studies. Pooled estimates of the effect of alcohol consumption on the risk of each investigated condition were based on a four-step procedure. Meta-regression models were fitted considering fixed and random-effect models and linear and nonlinear effects of alcohol intake. Results Of the 561 initially reviewed studies, 156 were selected for meta-analysis because of their quality. They included a total of 116 702 subjects. Strong trends in risk were observed for hypertension, liver cirrhosis, chronic pancreatitis, injuries, violence and for cancers of the oral cavity, oesophagus and larynx. Less strong relationships were observed with cancers of the colon, rectum, liver and breast. For all these conditions, significant increased risks were also found for ethanol intake of 25 g per day. Threshold values were observed for ischaemic and haemorrhagic strokes. For coronary heart disease, a J-shaped relationship was observed with a minimum RR of 0.80 at 20 g ethanol/day, a significant protective effect up to 72 g/day, and a significant increased risk at 89 g/day. No clear relationship was observed for gastroduodenal ulcer. Conclusions This meta-analysis shows no evidence of a threshold effect for both neoplasms and several non-neoplastic diseases. A J-shaped distribution was observed only for coronary heart disease.

Formocresol and ferric sulfate have similar success rates in primary molar pulpotomy. In carious primary molars does a pulpotomy performed with ferric sulphate, compared with formocresol, result in greater clinical/radiographic success?

Abstract: Medline Ovid Library, the Cochrane Library, PubMed, Embase, Science Citation Index (SCI) and System for Information on Grey Literature in Europe (SIGLE). Reviews, full reports, or research abstracts of prospective, retrospective, comparative, and/or radiographic studies were included, while case reports and letters were excluded. A total of 13 studies (three randomized clinical trials and 10 clinical trials) contributed to the meta-analysis, one randomized clinical trial and one clinical trial were analyzed by the direct technique, and all 13 trials were analyzed by the indirect technique. Data from trials were divided into clinical and radiographic data, and separate statistical analyses were conducted using the direct technique. Odds ratios (ORs) were used to compare the relative success of ferric sulphate and formocresol. Data homogeneity was tested using the χ2-test of consistency on the ORs for each trial. Clinical data indicated that ferric sulphate was significantly more successful than formocresol (OR=1.95; CI=1.01–3.80). Radiographic data indicated no difference between medicaments (OR=0.90; CI=0.58–1.39). Medicaments did not differ with t-tests of clinical (P>0.10) and radiographic (P>0.50) data. In human carious primary molars with reversible coronal pulpitis, pulpotomies performed with either formocresol or ferric sulphate are likely to have similar clinical/radiographic success.

Prosthetic posterior teeth with cusps may improve patient satisfaction with complete dentures.

Abstract: Prosthetic posterior teeth with cusps may improve patient satisfaction with complete dentures

Although leukoplakia responds to some treatments relapses and adverse effects are common

Abstract: The Cochrane Oral Health Group's Trials Register, Cochrane Central Trials Register, Medline and Embase were searched, as well as the following journals: Cancer, Community Dentistry and Oral Epidemiology, European Journal of Oral Sciences, Journal of Dental Research, Oral Oncology, Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endodontics. The reference lists of included studies and reviews were checked, and oral medicine experts were contacted through a European mailing list (EURORALMED). Randomised controlled trials (RCT) were included if they had enrolled patients who had a diagnosis of oral leukoplakia and who were undergoing any surgical or medical (topical and systemic) treatment. The primary outcome considered was malignant transformation of leukoplakia demonstrated by histopathological examination. Other outcomes considered were clinical resolution, histological modification and frequency of adverse effects. Data were collected using a specific extraction form. The validity of studies included was assessed by two reviewers, on the basis of the method of allocation concealment, blindness of the study and loss of participants. Data were analysed by calculating relative risk (RR). When valid and relevant data were collected, a meta-analysis of the data was undertaken. The possible effectiveness of surgical interventions, including laser therapy and cryotherapy, has never been studied by means of an RCT. Nineteen RCT of nonsurgical interventions were identified: seven were included. Vitamin A and retinoids were tested in five RCT (245 patients); the other drugs tested were bleomycin (one study), mixed tea (one study) and beta-carotene (one study). Malignant transformation was recorded in just two studies. None of the treatments tested showed a benefit compared with placebo. Treatment with beta-carotene and vitamin A or retinoids was associated with significant rates of clinical resolution, compared with placebo or absence of treatment. Whenever reported, a high rate of relapse was a common finding. Side effects of variable severity were often described but interventions were well accepted by patients, since dropout rates were similar between treatment and control. To date there is no evidence of effective treatment in preventing malignant transformation of leukoplakia. Treatments may be effective in the resolution of lesions, but relapses and adverse effects are common.

Temporomandibular articular disorders can be alleviated with surgery

Abstract: Medline, Embase and a variety of other sources were searched for English-language articles. Non-journal publications, conferences proceedings from professional organisations and from private and government agencies were screened. Bibliographies and reference lists from peer-reviewed and ‘grey’ literature were also reviewed. To meet the inclusion criteria articles must have reported studies of at least 10 patients, involve diagnoses of disc displacement with reduction (DDwR) or without reduction (DDw/oR) or degenerative joint disease (DJD) and include at least one of the following surgical techniques: arthrocentesis; arthroscopy; discectomy without replacement or disc repair/repositioning. The outcome measured was the proportion of patients who reported improvement after treatment. Study success rates were recalculated on an intent-to-treat basis. Meta-analyses were performed along with meta-regressions where heterogeneity was an issue. Three classes of meta-analyses were performed using different artificial, untreated, control groups assuming three levels of spontaneous improvement, namely 0, 37.5 and 75%. Twenty-two studies, comprising 30 patient groups and sample sizes of 11–237 patients, met the inclusion criteria. For studies of patients with DDwR, at the 0 and 37.5% rates of control group improvement, arthroscopy and disc repair/repositioning resulted in treatment effects significantly greater than zero, with no significant differences in the efficacy of these two surgical techniques. For studies of patients with DDw/OR, the proportion of patients who improved after arthroscopy or arthrocentesis was significantly greater than zero at all three levels of estimated control improvement. Disc repair effect size was not significant at the 75% rate. Surgical treatments appear to have some efficacy for people who have temporomandibular articular disorders that do not respond to nonsurgical therapies.

Antibiotics do not reduce toothache caused by irreversible pulpitis

Abstract: DATA SOURCES Cochrane Oral Health Group Trials Register and the Pain, Palliative Care and Supportive Care Group Trials Register, the Cochrane Central Register of Controlled Trials, Medline and Embase. STUDY SELECTION Randomised controlled trials (RCT) were included that involved patients over the age of 18 years who had presented with a single tooth with a clinical diagnosis of irreversible pulpitis. DATA EXTRACTION AND SYNTHESIS Abstracts of studies were independently assessed by two reviewers. The primary outcome was patient-reported pain (intensity/duration) and pain relief measured on a categorical scale in the preoperative phase of irreversible pulpitis. Secondary outcomes were type, dose and frequency of medication required for pain relief. Only one trial was included so pooling of data from studies was not possible and a descriptive summary is presented. RESULTS One trial of 40 participants was included. There was a close parallel distribution of the pain ratings in both the intervention and placebo groups over the 7-day study period. The between-group differences in sum pain intensity differences for the penicillin group were 6.0+/-10.5, and for placebo 6.0+/-9.5 (P=0.776; differences assessed by Mann-Whitney-Wilcoxon test considered to be statistically significant at P=0.05). The sum pain percussion intensity differences for the penicillin group were 3.5+/-7.5 and placebo 2.0+/-7.0 (P=0.290). There was no significant difference in the mean total number of ibuprofen tablets (P=0.839) and acetaminophen tablets (P=0.325) taken for pain relief in either group over the study period. The administration of penicillin over placebo did not appear to significantly reduce the quantity of analgesic medication taken (P=0.05) for irreversible pulpitis. CONCLUSIONS This review based on one methodologically sound but low-powered small sample trial, provides some evidence that there is no significant difference in pain relief between individuals who had untreated irreversible pulpitis who did or did not take antibiotics in addition to analgesics.