A video-based decision aid improved knowledge and decreased decisional conflict for asymptomatic persistent endodontic lesions.

AIM: This prospective cohort study aimed to (i) evaluate patients' treatment decisions, decisional conflict and knowledge levels before and after use of a video-based decision aid (DA) on asymptomatic persistent endodontic lesions (APEL) and to (ii) elicit important decision factors for patients in the decision-making process. METHODOLOGY: A video DA modelled after the International Patient Decision Aids Standards (IPDAS) was designed. The video was pilot-tested, revised and used on 50 patients referred to the graduate endodontic clinic and presenting with an incidental finding of APEL detected on radiographs, with informed consent (DSRB 2020/00133). Recruitment was conducted from June 2020 to November 2021. Patients' treatment decisions and decision-making process were studied. Patients also completed a questionnaire on knowledge gain, decisional conflict and confidence levels. RESULTS: Forty-three patients (48 teeth) out of 50 patients chose long-term monitoring of APEL while 7 patients (7 teeth) decided on endodontic intervention. Median knowledge scores increased from 58.3 (IQR: 41.7, 75.0) to 87.5 (IQR: 75.0, 100.0) (p < .001); median decisional conflict scale (DCS) scores decreased from 25.0 (IQR: 12.5, 34.4) to 3.1 (IQR: 0, 23.8) (p < .001), and 44 (88%) patients were confident or very confident with their treatment decisions. Statistical analyses showed that asymptomatic condition of tooth was the sole decision factor with statistical significance while socioeconomic factors (age, gender, race, education and income levels) showed no significant trend. CONCLUSIONS: The majority of patients presenting with APEL in this study chose long-term monitoring over immediate intervention. Using the video-based DA in the decision-making process significantly improved patients' knowledge and decreased their decisional conflict levels.

Primary apical periodontitis correlates to elevated levels of interleukin-8 in a Swedish population: A report from the PAROKRANK study.

AIM: To explore associations between root filled teeth, primary and secondary apical periodontitis, and levels of inflammatory markers in blood from patients with a first myocardial infarction and matched controls. METHODOLOGY: Between May 2010 and February 2014, 805 patients with a first myocardial infarction and 805 controls, matched for sex, age, and postal code area, were recruited to the multicentre case-control study PAROKRANK (periodontitis and its relation to coronary artery disease). All participants underwent a physical and oral examination, as well as blood sampling. Using panoramic radiography, root filled teeth, primary apical periodontitis, and secondary apical periodontitis were assessed by three independent observers. Blood samples were analysed with enzyme-linked immunosorbent assay method for the following inflammatory markers: interleukin-1ß (IL-1ß), IL-2, IL-6, IL-8, IL-12p70, tumour necrosis factor-α, and high-sensitivity C-reactive protein (hsCRP). Additionally, white blood cell count and plasma-fibrinogen were analysed. Associations between endodontic variables and the levels of inflammatory markers were statistically analysed with Mann-Whitney U-test and Spearman correlation, adjusted for confounding effects of baseline factors (sex, age, myocardial infarction, current smoking, diabetes, family history of cardiovascular disease, education, marital status, and periodontal disease). RESULTS: Mean age of the cohort was 62 years, and 81% were males. Root fillings were present in 8.4% of the 39 978 examined teeth and were associated with higher levels of hsCRP, fibrinogen, and leukocyte count, but lower levels of IL-2 and IL-12p70. After adjusting for confounders, root filled teeth remained associated with higher levels of fibrinogen, but lower levels of IL-1ß, IL-2, IL-6, and IL-12p70. Primary apical periodontitis was found in 1.2% of non-root filled teeth and associated with higher levels of IL-8 (correlation 0.06, p = .025). Secondary apical periodontitis was found in 29.6% of root filled teeth but did not relate to the levels of any of the inflammatory markers. CONCLUSIONS: This study supports the notion that inflammation at the periapex is more than a local process and that systemic influences cannot be disregarded. Whether the observed alterations in plasma levels of inflammatory markers have any dismal effects on systemic health is presently unknown but, considering the present results, in demand of further investigation.

Clinical decision making of post-treatment disease.

Root-filled teeth presenting with signs of post-treatment disease is a common finding in virtually every dental practice. There is both empirical and experimental evidence that, as long as the condition is asymptomatic, it is often left untreated. Professional judgements and decision making in endodontics as in any medical discipline are based on qualified estimations of the probability and the value of relevant outcomes. In this paper we describe various aspects of clinical decision making in general, from a descriptive as well as a normative point of view, but with a particular focus on the condition of the root-filled tooth with post-treatment disease. We review how attention to various types of uncertainties are relevant for the decision-making process. Additionally, we discuss the nature of value judgements and different concepts of health and disease which are important for understanding the complexity of the clinical decision-making process. We also refer to a set of principal rules that can guide the clinician's decision making in every-day practice in front of a case with endodontic post-treatment disease. Finally, we provide some aspects on the sometime cumbersome decision whether to go for a non-surgical or surgical method, whenever a decision on retreatment has been made.

Periradicular surgery: a longitudinal registry study of ten-year outcomes and factors predictive of post-surgical extraction.

AIM: This historical prospective cohort study of the adult population of Sweden is based on data from a national registry: the primary aim was to evaluate the long-term survival of teeth after periradicular surgery. A secondary aim was to identify factors predictive of extraction within 10 years of registration of periradicular surgery. METHODOLOGY: The cohort consisted of all individuals who had undergone periradicular surgery to treat apical periodontitis, as reported to the Swedish Social Insurance Agency (SSIA) during 2009. The cohort was followed until December 31, 2020. Subsequent registrations of extractions were collected for Kaplan-Meier survival analyses and survival tables. The patients' sex, age, dental service provider and tooth group were also retrieved from SSIA. Only one tooth per individual was included in the analyses. Multivariable regression analysis was used and P < 0.05 was considered statistically significant. The reporting guidelines STROBE and PROBE were followed. RESULTS: After data cleaning, and exclusion of 157 teeth, 5 622 teeth/individuals remained for analysis. The mean age of the individuals at the time of the periradicular surgery was 60.5 years (range 20-97, standard deviation 13.31); 55% were women. At the end of the follow-up, that is, up to 12 years, a total of 34.1% of the teeth had been reported as extracted. The multivariate logistic regression analysis, based on follow-up data at 10 years after registration of the periradicular surgery, included 5 548 teeth, of which 1 461 (26.3%) had been extracted. Significant associations between the independent variables tooth group and dental care setting (both P < 0.001) and the dependent variable extraction were found. The highest odds ratio (OR) for extraction applied to tooth group: compared to maxillary incisors and canines, mandibular molars were at greatest risk of extraction (OR 2.429, confidence interval 1.975-2.987, P < 0.001). CONCLUSIONS: After periradicular surgery in predominantly elderly people in Sweden, approximately three quarters of the teeth are retained over a 10-year period. The type of tooth is associated with extraction: mandibular molars are at greater risk of extraction than maxillary incisors and canines.

Periapical status and technical quality in root canal filled teeth in a cross sectional study in Jönköping, Sweden.

OBJECTIVE: To investigate the quality of root canal fillings and frequency of apical periodontitis (AP) in root canal filled teeth in a Swedish population. MATERIAL AND METHODS: This study used data from a cross-sectional survey conducted in 2013. The root canal filling quality and periapical status were assessed in 491 root canal filled teeth in 196 individuals aged 20-70 years, randomly selected from the population of Jönköping, Sweden. All root canal filled teeth were examined with periapical radiographs. Three calibrated observers recorded length and density in root canal fillings as well as periapical status according to the Periapical Index. A root filling ending within 0.5-2 mm from the radiographic apex without lateral or apical voids was considered adequate. Data were analyzed in a generalized estimating equation (GEE) model with AP as dependent variable and gender, age, number of teeth, number of root filled teeth, tooth type, and root filling quality as independent variables. RESULTS: Teeth with technically inadequate root fillings were associated with AP in a simple GEE-analysis. In the multiple GEE-model, the association between technical quality and apical peridontitis was nonsignificant when controlling for tooth type and gender. CONCLUSIONS: The quality of root canal fillings is poor and the prevalence of AP in root canal filled teeth is high, particularly in molar teeth, in a Swedish population.

Cost-effectiveness of partial versus stepwise caries removal of deep caries lesions - a decision-analytic approach.

OBJECTIVE: The aim was to compare the cost-effectiveness of partial caries removal (PCR) and stepwise caries removal (SW) in mature permanent teeth diagnosed with deep caries lesions, in a Swedish Public Dental Care organization. MATERIALS AND METHODS: A decision tree model was used to calculate the cost-effectiveness for PCR and SW. Probability values were obtained through a literature search in PubMed and Scopus. Treatment times were estimated by a group of dentists practicing at public dental care clinics in Västra Götaland county, Sweden. RESULTS: The expected costs for PCR and SW were 187,63 and 414,35 €, respectively, indicating that PCR was more cost-effective. Four articles were identified through the literature search. The p-values for PCR outcomes were 94% (success), 0% (pulp exposure) and 6% (pulpitis/apical periodontitis etc.). For SW, the p-values were 76% (success), 2% (pulp exposure during the first visit), 13% (pulp exposure during the second visit) and 9% (pulpitis/apical periodontitis etc.). CONCLUSIONS: Given the presumptions in this decision analysis, the PCR method used on mature permanent teeth is more cost-effective (p < ,05) compared to the SW method in protecting the pulp from exposure and avoiding the need for root canal treatment.

The efficiency of artificial intelligence methods for finding radiographic features in different endodontic treatments - a systematic review.

OBJECTIVES: To assess the efficiency of AI methods in finding radiographic features in Endodontic treatment considerations. MATERIAL AND METHODS: This review was based on the PRISMA guidelines and QUADAS 2 tool. A systematic search was performed of the literature on cases with endodontic treatments, comparing AI algorithms (test) versus conventional image assessments (control) for finding radiographic features. The search was conducted in PubMed, Scopus, Google Scholar and the Cochrane library. Inclusion criteria were studies on the use of AI and machine learning in endodontic treatments using dental X-rays. RESULTS: The initial search retrieved 1131 papers, from which 24 were included. High heterogeneity of the materials left out a meta-analysis. The reported subcategories were periapical lesion, vertical root fractures, predicting root/canal morphology, locating minor apical foramen, tooth segmentation and endodontic retreatment prediction. Radiographic features assessed were mostly periapical lesions. The studies mostly considered the decision of 1-3 experts as the reference for training their models. Almost half of the included materials campared their trained neural network model with other methods. More than 58% of studies had some level of bias. CONCLUSIONS: AI-based models have shown effectiveness in finding radiographic features in different endodontic treatments. While the reported accuracy measurements seem promising, the papers mostly were biased methodologically.

Patient record assessment of results and related resources spent during 1 year after initiation of root canal treatment in a Swedish public dental organization.

AIM: To document treatment outcomes and related resources, in patients undergoing root canal treatment (RCT) in county public dental clinics, by monitoring patient records for 12 months from treatment start. METHODOLOGY: The subjects comprised 243 patients starting RCT at 20 public dental clinics in Västra Götaland county, Sweden. Their computerized dental records were monitored prospectively for a year after starting their endodontic treatment. Treatment was completed with either a root filling or extraction. The following treatment-specific variables were registered: number of appointments and days until treatment was completed, possible complications and prescriptions for antibiotics, and for the root filled teeth: type of coronal restoration and further procedures undertaken within the year. The treatment outcomes were compared with the preoperative variables and in a logistic regression analysis. RESULTS: Complete data were available for 240 patients (98.8%): 128 women and 112 men, with a mean age of 48.5 years (SD = 16.3). Molar teeth predominated (n = 113, 47.1%). Most cases were completed with a root filling (n = 169, 70.4%). The remainder were extracted (n = 32, 13.3%) or were still uncompleted (n = 39, 16.3%). On average, a root filling was completed in 2.4 (SD = 0.9) appointments, or extraction at the third appointment (SD = 1.6). The molars were less often completed and often predominant among the extracted teeth. The indication for extraction was often for endodontic or RCT-related reasons. Most complications were registered in the molars and antibiotics were prescribed in 20 cases. Most root filled teeth were restored with a direct restoration. Four root filled teeth (2.4%) were extracted within the time period. CONCLUSIONS: Patient records, followed from the start of treatment, show that 12 months on, the root filling had not been completed in just under 30% of the teeth. Of these, about half were extracted. Of particular concern is the outcome for endodontic treatment of molar teeth. In the general practice setting, molar endodontics are not only technically challenging but also very demanding in terms of chairside resources. In the present study, a successful outcome was achieved in just over half the cases.

Endodontic inflammatory disease: A risk indicator for a first myocardial infarction.

AIM: To study the association between endodontic inflammatory disease and a first myocardial infarction (MI). METHODOLOGY: The study comprised 805 patients with recent experience of a first MI, each gender, age and geographically matched with a control. Panoramic radiographs were available for 797 patients and 796 controls. Endodontic inflammatory disease was assessed radiographically. The sum of decayed, missing and filled teeth (DMFT) was calculated, and the number of root filled teeth and teeth with periapical lesions were recorded. The associated risk of a first MI was expressed as odds ratios (OR) with 95% confidence intervals (CI), unadjusted and adjusted for confounders (family history of cardiovascular disease, smoking habits, marital status, education and diabetes). RESULTS: Patients who had suffered a first MI had higher DMFT (mean 22.5 vs. 21.9, p = .013) and more missing teeth (mean 7.5 vs. 6.3; p < .0001) than the healthy controls. The number of missing teeth was associated with an increased risk of a first MI (adjusted OR 1.04; CI 1.02-1.06). Conversely, decay-free, filled teeth were associated with decreased risk (adjusted OR 0.98; CI 0.96-1.00). Analysis based on age disclosed the following variables to be associated with an increased risk of a first MI: number of decayed teeth (adjusted OR 1.18; CI 1.02-1.37, in patients <60 years), any primary periapical lesion (adjusted OR 1.57; CI 1.08-2.29, in patients <65 years) and the proportion of root filled teeth (adjusted OR 1.18; CI 1.03-1.36, in patients ≥65 years). CONCLUSIONS: More missing teeth was independently associated with an increased risk of a first MI. In addition, endodontic inflammatory disease may contribute as an independent risk factor to cardiovascular disease since untreated caries, periapical lesions and root fillings, depending on age, were significantly associated with a first MI.

Computed Tomography-Derived Fractional Flow Reserve in Patients With Chronic Coronary Syndrome: A Real-World Cohort Study.

OBJECTIVE: This study aimed to investigate the outcome of computed tomography (CT) angiography with optional CT-derived fractional flow reserve (FFRCT) of intermediate-range coronary artery disease in non-emergent patients referred on a suspicion of chronic coronary syndrome. METHODS: Patients were classified as high risk and low-intermediate risk according to the presence of typical angina or either atypical or nonangina chest pain. Outcome was assessed as the cumulative incidence proportion of a composite end point of unstable angina pectoris, unplanned revascularization, nonfatal myocardial infarction, and all-cause mortality. RESULTS: The study included 743 patients. Mean follow-up was 2.2 (range, 0.1-2.5) years. Low-intermediate-risk and high-risk patients who had invasive coronary angiography deferred had comparable proportions of adverse events (1.4% vs 2.6% [P = 0.27]). Adverse events in high-risk patients with FFRCT >0.80 was 3.3% versus 1.4% in patients where no additional testing was performed (P = 0.79). CONCLUSIONS: Computed tomography-derived fractional flow reserve >0.8 conveys an excellent prognosis. Computed tomography angiography with optional FFRCT allows for the safe cancellation of invasive coronary angiography in high-risk patients.

Calibration improves observer reliability in detecting periapical pathology on panoramic radiographs.

OBJECTIVE: To determine whether calibration improves observer reliability when assessing DMFT-score, root-filled teeth and periapical lesions on panoramic radiographs. MATERIAL AND METHODS: A sample of 100 panoramic radiographs was selected from a cohort of myocardial infarction patients (n = 797) and matched controls (n = 796). The following variables were assessed: DMFT-score, remaining teeth, root-filled teeth and periapical lesions. Two specialists, an endodontist and a radiologist, served as reference examiners and undertook two separate assessments. Disagreement cases were jointly assessed and the final results were used as the reference standard. Three observers undertook three separate assessments, the first without prior training, the second after calibration against the reference standard and the third with the sample concealed in the complete material. Statistical analysis was made with Wilcoxon Signed rank test and Sign test. Agreement was calculated as Intraclass Correlation Coefficient (ICC) (95% CI) and Weighted Kappa (κ) (95% CI). RESULTS: Periapical lesions disclosed high inter-observer variability for the reference examiners and diverged significantly between the observers and the reference standard. For the reference examiners, inter-observer agreement was κ = 0.53. The observers, in their first assessments had κ values ranging from 0.22 to 0.60 in relation to the reference standard. Following calibration, the κ values increased, ranging from 0.59 to 0.80. For the third assessment, the κ values ranged from 0.54 to 0.75. DMFT-score, remaining teeth and root-filled teeth disclosed high reliability throughout all assessments (ICC = 0.88-0.98 and κ = 0.98-0.99). CONCLUSIONS: DMFT-score, remaining teeth and root-filled teeth can be reliably assessed on panoramic radiographs. Calibration against a reference standard improves observer reliability in the detection of periapical lesions.

Xdrop: Targeted sequencing of long DNA molecules from low input samples using droplet sorting.

Long-read sequencing can resolve regions of the genome that are inaccessible to short reads, and therefore are ideal for genome-gap closure, solving structural rearrangements and sequencing through repetitive elements. Here we introduce the Xdrop technology: a novel microfluidic-based system that allows for targeted enrichment of long DNA molecules starting from only a few nanograms of DNA. Xdrop is based on the isolation of long DNA fragments in millions of droplets, where the droplets containing a target sequence of interest are fluorescently labeled and sorted using flow cytometry. The final product from the Xdrop procedure is an enriched population of long DNA molecules that can be investigated by sequencing. To demonstrate the capability of Xdrop, we performed enrichment of the human papilloma virus 18 integrated into the genome of human HeLa cells. Analysis of the sequencing reads resolved three HPV18-chr8 integrations at base-pair resolution, and the captured fragments extended up to 30 kb into the human genome at the integration sites. Further, we enriched the complete TP53 locus in a leukemia cell line and could successfully phase coexisting mutations using PacBio sequencing. In summary, our results show that Xdrop is an efficient enrichment technology for studying complex genomic regions.

Is apical periodontitis in root filled teeth associated with the type of restoration?

OBJECTIVE: To study the association between type of restoration and apical periodontitis (AP) in root filled teeth. MATERIALS AND METHODS: The present study used data from surveys conducted in 1983, 1993 and 2003. In 1983, 130 randomly selected subjects aged 3-80 years in the city of Jönköping, Sweden, were invited for a clinical and radiological examination. The study was repeated in 1993 and 2003. New participants were, thus, recruited with the same sampling criteria and sample size in the same geographical area in 1993 and 2003, respectively. In the present study, only dentate individuals aged 20-70 years with ≥1 root filled tooth were included, yielding a sample of 788 subjects with 2634 root filled teeth. Apical periodontitis on the tooth level was the dependent variable. Periapical status was assessed according to Periapical Index (PAI). Independent variables were root filling quality, recurrent caries, type of restoration, number of teeth with apical periodontitis, age and gender. Root fillings appearing homogenous and ending within 2 mm from radiographic apex were regarded as adequate, otherwise inadequate. All radiographs were re-studied by one observer regarding periapical status and root filling quality. Risk was analyzed by means of a GEE model. RESULTS: Type of restoration, root filling quality, number of teeth with apical periodontitis within the individual and age were found to be predictors of AP in root filled teeth. Presence of recurrent caries and gender were not found to be associated with AP. CONCLUSIONS: According to the present study, root filling quality and type of restoration may be predictive of AP in root filled teeth.

Endodontic Inflammatory Disease and Future Cardiovascular Events and Mortality: A Report from the PAROKRANK Study.

INTRODUCTION: Prospective studies assessing the relation between endodontic inflammatory disease and subsequent cardiovascular events are few. The present aim was to explore associations between endodontic variables and future cardiovascular events in patients with myocardial infarction and matched controls participating in the PAROKRANK (Periodontitis and Its Relation to Coronary Artery Disease) study. METHODS: Eight-hundred five patients hospitalized for a first myocardial infarction and 805 controls were recruited between 2010 and 2014. Signs of endodontic inflammatory disease were assessed in panoramic radiographs taken at baseline. Mortality and morbidity data during the approximately 8 years of follow up were obtained from national registries. The risk for future cardiovascular events (first of mortality and nonfatal myocardial infarction, stroke, or hospitalization for heart failure) was analyzed with the log-rank test and Cox proportional hazards regression adjusted for the following confounders: sex, age, smoking, myocardial infarction, diabetes, education, marital status, family history of cardiovascular disease, and marginal periodontitis. RESULTS: In total, 285 future events were observed during the follow-up period. Unadjusted analyses revealed that ≥1 root-filled tooth increased the risk of a future event. After adjustment, the number of remaining teeth and non-root-filled teeth decreased the risk of future events, whereas a higher Decayed, Missing and Filled Teeth score increased the risk and ≥1 primary apical periodontitis decreased the risk of suffering cardiovascular events. A higher Decayed, Missing and Filled Teeth score and decayed teeth increased the risk of all-cause mortality. CONCLUSIONS: Tooth loss is a strong indicator of an increased risk for future cardiovascular events. Root-filled teeth seem of limited value as a risk indicator when accounting for other risk factors. The potential effect of dental interventions on future events should be assessed in future research.

Treatment of pulps in teeth affected by deep caries - A systematic review of the literature.

BACKGROUND: This systematic review assesses the effect of methods commonly used to manage the pulp in cases of deep caries lesions, and the extent the pulp chamber remains uninfected and does not cause pulpal or periapical inflammatory lesions and associated tooth-ache over time. STUDY DESIGN: An electronic literature search included the databases PubMed, EMBASE, The Cochrane Central Register of Controlled Trials and Cochrane Reviews from January 1950 to March 2013. In addition, hand searches were carried out. Two reviewers independently evaluated abstracts and full-text articles. An article was read in full if at least one of the two reviewers considered the abstract potentially relevant. Altogether, 161 articles were read in full text. Of these, 24 studies fulfilled established inclusion criteria. Based on studies of at least moderate quality, the quality of evidence of each procedure was rated in four levels according to GRADE. RESULTS: No study reached the high quality level. Twelve were of moderate quality. The overall evidence was insufficient to assess which of indirect pulp capping, stepwise excavation, direct excavation and pulp capping/partial pulpotomy, pulpotomy or pulpectomy is the most effective treatment approach for teeth with deep caries. CONCLUSIONS: Because of the lack of good studies it is not possible to determine whether an injured pulp by deep caries can be maintained or whether it should be removed and replaced with a root canal filling. Both randomized studies and prospective observational studies are needed to investigate whether a pulp exposed to deep caries is best treated by measures intended to preserve it or by pulpectomy and root filling.

Pulp exposures in adults--choice of treatment among Swedish dentists.

This study comprises a survey of Swedish dentists'treatment preferences in cases of carious exposure of the dental pulp in adults.The survey was conducted as part of a comprehensive report on methods of diagnosis and treatment in endodontics, published in 2010 by the Swedish Council on Health Technology Assessment. A questionnaire was mailed to a random subsample of 2012 dental offices where one dentist at each office was requested to answer all questions. Each questionnaire contained one of three sets of questions about endodontic practice routines.Thus around one-third of the subsample received case-specific questions about treating carious exposure. Only general practitioners aged below 70 years were included.The final study sample comprised 412 participants.The dentists were presented with two case scenarios. In Case 1 a 22-year old patient had a deep carious lesion in tooth 36 and in Case 2 a 50-year old patient had a deep carious lesion in tooth 14.The participants were asked to nominate their treatment of choice: pulp capping, partial pulpotomy or pulpectomy. For Case 1, 17 per cent of the respondents selected pulpectomy; the corresponding rate for Case 2 was 47 per cent. Female gender and age group 25-49 years were predictive of selection of less invasive treatment options. However, according to recent guidelines (2011) from the National Board of Health and Wellfare, Swedish dentists are recommended to elect pulpectomy prior to pulp capping/partial pulpotomy when confronted with a tooth having a cariously exposed pulp in adults.

Endodontic retreatment decision-making: The influence of the framing effect.

OBJECTIVE: The aim of this study was to explore the influence of a framing effect in retreatment decision-making of a root-filled tooth with asymptomatic apical periodontitis (AP). METHOD: Two variants of a questionnaire were created in which the factual information about a root filled with AP was identical. The options in the first variant were framed in favor to wait and see (FW) and those in the other variant were framed in favor of retreatment (FR) Two hundred and forty-eight volunteers were by chance given one of the two versions and were asked to choose between having retreatment or to wait and see. RESULTS: Of the 125 participants given the FW version, 69 (55.2%) chose to wait and see while out of the 123 participants who were given the FR version, 38 (30.9%) made the alike choice (p = .0002). CONCLUSION: A framing effect is likely to play an essential role in endodontic retreatment decision-making of root-filled teeth with asymptomatic apical periodontitis.

Cost-effectiveness of root canal treatment compared with tooth extraction in a Swedish Public Dental Service: A prospective controlled cohort study.

OBJECTIVES: To evaluate the cost-effectiveness of root canal treatment (RCT) compared with a tooth extraction in a general dental practice setting, with reference to cost per quality-adjusted life-year (QALY) gained over 1 year. MATERIAL AND METHODS: This is a prospective controlled cohort study based on patients either starting RCT or undergoing extraction at one of six Public Dental Service clinics in the county of Västra Götaland, Sweden. From a total of 65 patients, 2 comparable groups were formed: 37 started RCT and 28 underwent extraction. A societal perspective was used for the cost calculations. QALYs were estimated, based on the EQ-5D-5L given to the patients at their first treatment appointment and then after 1, 6, and 12 months. RESULTS: The total mean cost of RCT ($689.1) was higher than for extraction ($280.1). For those patients whose extracted tooth was replaced, the costs were even higher ($1245.5). There were no significant intergroup differences in QALYs, but a significant improvement in health state values in the tooth-preserving group. CONCLUSIONS: In the short term, extraction was cost-effective compared with preserving a tooth with RCT. However, the potential need for future replacement of the extracted tooth, by an implant, fixed prosthesis, or removable partial dentures, may change the calculation in favor of RCT.

A Weighted Composite of Endodontic Inflammatory Disease is Linked to a First Myocardial Infarction.

PURPOSE: To explore a weighted composite of endodontic inflammatory disease (EID) as a risk factor for suffering a first myocardial infarction (MI). MATERIALS AND METHODS: Seven tooth-specific conditions related to EID were assessed radiographically in 797 patients suffering a first MI and 796 controls. A weighted composite of EID was calculated as the sum of all teeth, excluding third molars. Using maximum likelihood estimation, each condition was assigned a specific weight. With multivariable conditional regression, EID variables, periodontal disease, and missing teeth were assessed as predictors of a first MI. RESULTS: Periodontal disease (OR 1.38; 95% CI 1.13-1.69, p = 0.0016) and missing teeth (OR 1.03; 95% CI 1.002-1.05, p = 0.034) were related to the risk of a first MI, while none of the EID-related conditions individually were. However, when assessed as an aggregate, a weighted composite of EID (OR 1.97; 95% CI 1.23-3.17, p = 0.0050) and periodontal disease (OR 1.34; 95% CI 1.09-1.63, p = 0.0046) was associated with the risk of MI. Missing teeth did not remain a statistically significant predictor of MI in the final model. CONCLUSIONS: A weighted composite of EID was associated with the risk of MI and strengthens the evidence for a direct connection between oral inflammatory diseases and cardiovascular disorders.

Fermentation of crude glycerol from biodiesel production by Clostridium pasteurianum.

Clostridium pasteurianum can utilize glycerol as the sole carbon source for the production of butanol and 1,3-propanediol. Crude glycerol derived from biodiesel production has been shown to be toxic to the organism even in low concentrations. By examination of different pretreatments we found that storage combined with activated stone carbon addition facilitated the utilization of crude glycerol. A pH-controlled reactor with in situ removal of butanol by gas stripping was used to evaluate the performance. The fermentation pattern on pretreated crude glycerol was quite similar to that on technical grade glycerol. C. pasteurianum was able to utilize 111 g/l crude glycerol. The average consumption rate was 2.49 g/l/h and maximum consumption rate was 4.08 g/l/h. At the maximal glycerol consumption rate butanol was produced at 1.3 g/l/h. These rates are higher than those previously reported for fermentations on technical grade glycerol by the same strain. A process including pretreatment and subsequent fermentation of the crude glycerol could be usable for industrial production of butanol by C. pasteurianum.