Outcomes of abutment teeth with double crowns over an observation period of 27 years.

PURPOSE: The aim of this retrospective study was to determine the outcome of double crowns (DCs) using pooled data over a period of 27 years. METHODS: Billing data were obtained from the digital accounting system of a university dental clinic. All DCs inserted and invoiced from January 1, 1992, to December 31, 2019, were collected. The maximum observation period of a DC was determined by a recorded follow-up or the occurrence of a target event. Target events were divided into primary, i.e., tooth extraction, and secondary, i.e., failure of DC, types. The dataset was analyzed using descriptive statistics and Kaplan-Meier survival and multivariate Cox regression analyses. RESULTS: A total of 4,097 tooth-supported DCs in 1,148 patients were included in the analysis. The mean observation period for individual DC was 5.32 years. The cumulative survival rates at 5 and 10 years for the primary target event were 89.7% and 73.8%, respectively. The cumulative survival rates at 5 and 10 years for the secondary target event were 83.6% and 60.6%, respectively. In the multivariate analysis, age and metal denture bases were significantly associated with both target events. CONCLUSIONS: This study confirmed DCs as a reliable and long-term successful treatment option for anchoring removable partial dentures. The use of a metal denture base and a younger patient age might reduce the risk of complications.

Associations of early childhood medication exposure and molar incisor hypomineralization (MIH): A routine data analysis.

OBJECTIVES: Molar incisor hypomineralization (MIH) has become a major oral health problem of widely unknown origin. Besides genetic predisposition, exposure to certain drugs in early childhood are suspected to be associated with MIH. Aim of this routine data analysis was to examine associations of MIH and exposure to medication as well as perinatal factors. METHODS: Individuals with MIH were identified in claims data using a validated predefined specific treatment pattern. The database was a comprehensive routine data set of a major national health insurance company (BARMER, Germany). Based on this treatment pattern a MIH group and an unaffected control group were formed for analysis. Various medical data including medical diagnoses and prescriptions were available. Associations were examined comparing results for a set of variables in both groups. Differences between the groups were tested for significance using T-tests (P<0.01). RESULTS: Between 2010 to 2019, a total of 298,502 children between 6 and 9 years of age were included in this analysis. 22,947 were assigned to the MIH group. For individuals in this group, significantly larger prescription quantities in the main ATC (Anatomical, Therapeutic, Chemical) groups J (antiinfectives for systemic use), R (respiratory system) and S (sensory organs) were found in the first 4 years of life compared to MIH unaffected individuals. With antibiotics, there were both significantly larger prescription quantities and significantly higher numbers of respective prescriptions in the first 4 years of life. The differences amounted up to about 10.62% in frequently used antibiotics to be found in ATC J01D (other beta-lactam antibacterials) for the number of prescriptions in the 4th year of life. No association was found for premature birth, mode of delivery or the use of antipyretic or anti-inflammatory medication. CONCLUSIONS: While perinatal factors do not seem to be associated with MIH development, early life exposure to antibiotics might play a role. CLINICAL SIGNIFICANCE STATEMENT: Although causal relations can still not be proven, a responsible use of the unquestionably beneficial antibiotics is encouraged from a clinical point of view.

Tooth loss in periodontally treated patients: A registry- and observation-based analysis.

AIM: According to retrospective clinical studies, periodontal treatment retains teeth. However, evidence on the effectivity of periodontal treatment stemming from the general population is lacking. MATERIALS AND METHODS: We analysed data of periodontally treated patients from routine data of a major German national health insurance (BARMER-MV; sub-sample of the Federal State of Mecklenburg-Vorpommern) and from a clinical cohort (Greifswald Approach to Individualized Medicine, GANI_MED), as well as periodontally untreated and treated participants of the Study of Health in Pomerania (SHIP-TREND) with either ≥2 or ≥4 teeth with pocket depths ≥4 mm. Yearly tooth loss (YTL) estimates and incidence rates were evaluated. RESULTS: For moderately to severely affected groups, YTL and incidence rates were higher in BARMER-MV patients (0.35 and 0.18, respectively) than in untreated SHIP-TREND controls (0.19 and 0.08, respectively). In line, treated SHIP-TREND participants exhibited higher YTL rates than untreated SHIP-TREND controls (0.26 vs. 0.19). For severely affected groups, results with respect to tooth loss were inconclusive regarding the beneficial effects of periodontal treatment conducted either in the university (GANI_MED data) or in the general practice. CONCLUSION: Until 2021, periodontal treatment performed in German general dental practices within the national health insurance system was probably not efficient in retaining more teeth in the short- to mid-term. Since reimbursement schemes were changed in 2021 and now cover periodontal treatment to a much larger extent, the future will show whether these new reimbursement codes will improve the quality of periodontal treatment and whether they will lead to more long-term tooth retainment.

Three-year clinical performance of posterior monolithic zirconia single crowns.

STATEMENT OF PROBLEM: Monolithic zirconia has become widely used for single crowns, with the advantages of minimal tooth reduction and good esthetics. However, clinical studies evaluating the performance of and patient satisfaction with posterior monolithic zirconia crowns are sparse. PURPOSE: The purpose of this clinical study was to evaluate the clinical performance of and patient satisfaction with posterior monolithic zirconia crowns. MATERIAL AND METHODS: Within a prospective cohort study design, participants were recruited from a university dental clinic if they required 1 posterior monolithic zirconia crown. The clinical performance was evaluated at follow-up appointments 1, 2, and 3 years after insertion. Bleeding on probing and pocket probing depths for the crowned teeth were recorded. Overall patient satisfaction was measured by using a visual analog scale (VAS), and quality of life was measured by using the validated German version of the Oral Health Impact Profile 14 (OHIP-G14). Descriptive statistical methods were applied. Mean values were calculated and compared by using the paired t test (α=.05). RESULTS: Thirty participants received a monolithic zirconia crown (14 premolars, 16 molars). One biologic complication (vertical root fracture) was identified at the 1-year follow-up. Three years after insertion, 22 participants could be examined, and the crowns were still in function. The gingival and the periodontal status of the crowned teeth had not changed significantly over the 3 years. After insertion, a significant improvement in patient satisfaction was measured up to 3 years CONCLUSIONS: Posterior monolithic zirconia crowns led to enhanced patient satisfaction up to 3 years after insertion. They provided good middle-term success and offered a promising alternative to conventional metal-ceramic crowns.

Performance of fixed dental prostheses up to 6 years-A massive data analysis.

STATEMENT OF PROBLEM: Metal and metal-ceramic fixed dental prostheses (FDPs) have been clinically determined to provide long-term durable restorations. However, data on their performance under practice conditions are sparse. PURPOSE: The purpose of this clinical study was to evaluate the longevity of FDPs under practice conditions by analyzing a large insurance claims database. MATERIAL AND METHODS: Data were extracted from the data warehouse of a major German national health insurance company (BARMER). The analysis focused on the FDP types with the lowest deductibles in the insurance system. All metal-based FDPs replacing up to 3 adjacent teeth were included. Ceramic veneering was optional and only approved on the labial surfaces of maxillary teeth mesial to the first molar and mandibular teeth mesial to the second premolar. Fee codes allowed clinical courses to be traced on a day count basis. Three groups with FDPs replacing 1 tooth, 2 teeth, and 3 teeth were formed. Kaplan-Meier survival analyses were conducted for the target events removal or extraction, indicating FDP failure and extraction of an abutment tooth. RESULTS: The sample comprised 124 660 FDPs that replaced 1 tooth (76.5%), 2 teeth (19.8%), or 3 teeth (3.7%). The cumulative survival rates for removal or extraction at 6 years differed significantly, with 83.0% for 1-pontic FDPs, 78.1% for 2-pontic FDPs, and 74.0% for 3-pontic FDPs. Thus, approximately 1 of 6 one-pontic FDPs, 1 of 5 two-pontic FDPs, and 1 of 4 three-pontic FDPs failed. The cumulative survival rates for extraction of an abutment tooth at 6 years showed no significant difference, with 96.0% for 1-pontic FDPs, 95.6% for 2-pontic FDPs, and 95.1% for 3-pontic FDPs. CONCLUSIONS: The survival rates of FDPs according to insurance data were lower than those reported by clinical studies, indicating a gap between efficacy and effectiveness.

Routine Data Analyses for Estimating the Caries Treatment Experience of Children.

Oral health surveys are considered the gold standard for assessing the caries experience of children. Analyses of routine data offer additional opportunities not yet fully explored. This study aimed at estimating the caries treatment experience by mining an insurance claims database. Comprehensive claims data sets were extracted from the data warehouse of a major health insurance company (BARMER, Germany). A surrogate variable for caries experience was formed that reflected the proportion of children without any former potentially caries-related treatment (filling, root canal treatment, and extraction) at ages from 1 to 14 years. The statistical calculations were based on Kaplan-Meier survival analyses. The evaluation for the permanent dentition comprised N = 593,330 children at 6 years and N = 114,568 at 12 years. At 12 years of age, 66.8% had not yet experienced potentially caries-related treatments. This value hints at a significantly higher caries experience at 12 years compared to available epidemiological data. For the deciduous dentition, the respective rates were 74.0% at 6 years and 45.8% at 10 years. Although various sources of bias have to be taken into account, the potential of routine data mining is evident. The approach is supplemental to oral health surveys. It can be useful in coming closer to reality when estimating the caries experience of children. From our results, we conclude that the oral health of up to 14-year-olds in Germany remains in urgent need of improvement.

Massive data analyses show negative impact of type 1 and 2 diabetes on the outcome of periodontal treatment.

OBJECTIVES: The aim was to evaluate the impact of diabetes on the outcome of periodontal treatment based on massive data analyses. MATERIALS AND METHODS: Data originated from the database of a major German National Health Insurance. Patients who underwent periodontal treatment were allocated to four groups according to their medical condition: type 1 diabetes (D1), type 2 diabetes with the intake of oral anti-diabetics (D2M), type 2 diabetes without the intake of oral anti-diabetics (D2), and a control group without diabetes (ND). Four-year Kaplan-Meier survival analyses on the patient level and multivariate regression analyses were conducted for tooth extraction. RESULTS: Of 415,718 patients, 4139 matched the criteria for D1, 22,430 for D2M, and 23,576 for D2. At 4 years, the cumulative survival rate (no extraction) was 51.7% in the D1 group, 54.0% in the D2M group, and 57.7% in the D2 group. The ND control group had a significantly higher survival rate of 65.9% (P < 0.0001). In the multivariate analyses, both diabetes types were significantly associated with further tooth loss after periodontal treatment. CONCLUSIONS: The diagnosis of diabetes type 1 or 2 seems to be associated with a higher risk of tooth loss after periodontal treatment. CLINICAL RELEVANCE: The long-term prognosis of teeth in diabetes patients should be judged carefully.

Six-year survival of single crowns - A massive data analysis.

OBJECTIVES: Numerous clinical trials have proven the long-term stability of metal and metal-ceramic crowns. However, data on their performance under practice conditions are rare. PURPOSE: To evaluate the longevity of crowns by means of massive data analyses. METHODS: The data were extracted from the data warehouse of a major German national health insurance company (BARMER, Berlin, Germany). The analysis focused on crown types with the lowest deductibles. Metal crowns and metal-ceramic crowns with ceramic veneering on the vestibular aspects of teeth 15-25 and 34-44 placed from 2012 to 2017 were included. The placement of the crowns, crown removals and tooth extractions were identified using the corresponding fee codes. Kaplan-Meier survival analyses were conducted for the outcomes "crown removal or extraction" and for "extraction". RESULTS: The cumulative six-year survival rates were 88.0 % for the outcome "crown removal or extraction" and 92.5 % for the outcome "extraction" (N = 192,868). The survival functions had slightly steepening but close to linear courses. CONCLUSIONS: The outcome of the treatment with metal and metal-ceramic crowns was moderately inferior in comparison to clinical trials. However, treatment with metal and metal-crowns is judged to be a reliable and safe option under practice conditions. CLINICAL SIGNIFICANCE STATEMENT: Clinicians must inform patients about potential treatment outcomes. Therefore, additional knowledge about single crown outcomes under general practice settings based on large database analyses is important.

Periodontal treatment and peripheral arterial disease severity - a retrospective analysis of health insurance claims data.

Background: Although epidemiological data suggest an association between periodontitis (PD) and peripheral arterial disease (PAD), it is currently unclear whether treatment of PD influences the severity of PAD. Patients and methods: Whether periodontal treatment is associated with PAD disease severity was examined by analysing health insurance claims data of patients insured by the German health insurance fund, BARMER, between January 1, 2012 and December 31, 2016. The presence of PAD was determined in individuals using International Classification of Diseases (ICD) 10th revision codes for intermittent claudication (IC) or chronic limb threatening ischaemia (CLTI). Treatment of PD was assessed by adequate ambulatory coding for non-surgical and surgical treatment of PD. Multivariate logistic regression analysis was performed to evaluate the association between PAD stages and periodontal treatment, adjusted for diabetes, age and sex. Results: The study cohort included 70,944 hospitalized patients with a diagnosis of symptomatic PAD (54.99 % women, 49.05 % IC). Among these patients, 3,567 (5.03 %) had received prior treatment for PD by supra- or sub-gingival debridement. PAD patients who had received periodontal treatment showed a lower proportion of CLTI (28.76 % among treated vs. 52.12 % among non-treated). Using multivariable regression methods, exhibiting a CLTI (vs. IC) was associated with not being treated for PD (Odds Ratio 1.97, 95 %-CI 1.83-2.13) after adjustment for age, gender, and diabetes. Conclusions: In this large-scale retrospective analysis of health insurance claims data comprising hospitalized symptomatic PAD patients, treatment of PD was associated with PAD disease severity independent of age, gender and diabetes. A potential benefit of periodontal treatment in relation to PAD will have to be determined in further prospective studies.

Stabilizing mandibular complete dentures by a single midline implant-influence on quality of life: 2-year results from a randomized clinical trial comparing different loading protocols.

OBJECTIVES: The knowledge about the influence of dental treatment on health-related quality of life (HRQoL) is still limited. The aim of this multicenter randomized controlled clinical trial was to assess the effect of stabilizing an existing complete denture, by means of a single mandibular implant, on HRQoL. Furthermore, the impact of the loading protocol, i.e., immediate or delayed loading, in edentulous patients was evaluated. METHODS: One hundred fifty-eight participants aged 60-89 years were randomly assigned to study group A (immediate loading; n = 81) and to group B (delayed loading; n = 78). All participants received a single midline implant in the mandible. The implants were either immediately loaded (group A) or after a closed healing period of 3 months (group B) by connecting the existing mandibular complete dentures to ball attachments. HRQoL was assessed with the Short Form-36 questionnaire of health (SF-36) at baseline, 4 months, and 24 months after implant loading. RESULTS: Improvement of HRQoL by means of a single implant-retained mandibular overdenture could not be demonstrated after 4 and 24 months of implant loading. Furthermore, the application of two different loading protocols did not influence HRQoL ratings of study participants. CONCLUSION: The loading protocol is not a factor, influencing HRQoL in patients treated by a single midline implant in the edentulous mandible. CLINICAL RELEVANCE: A single midline implant in the edentulous mandible, stabilizing a mandibular complete denture, cannot be recommended for improving HRQoL.

Tooth loss after periodontal treatment-Mining an insurance database.

OBJECTIVES: The aim of this study was to evaluate tooth loss after periodontal treatment. METHODS: The data was collected from the digital database of a major German national health insurance company. Periodontal treatment was the intervention in the treatment group. Kaplan-Meier survival analyses on the patient level with the primary outcome extraction were carried out over four years. A control group without treatment was matched and analysed. Differences were tested with the Log-Rank-test. Extraction incidences were calculated over a matched observation period six years before and four years after treatment for both treatment and control group. RESULTS: A total of 415,718 periodontal treatments could be traced. Focussing on the outcome "extraction", the cumulative four-year survival rate was 63.8% after periodontal treatment. The matched control group without periodontal treatment showed a survival rate of 72.5%. These differences were significant (p < 0.0001). The extraction incidence over time was higher in a four-year period after periodontal treatment compared to a six-year period before periodontal treatment. CONCLUSIONS: The outcome of periodontal treatment was acceptable. In about two thirds of the patients, extractions could be completely avoided within a four year period after treatment. CLINICAL SIGNIFICANCE STATEMENT: This study within the German national health insurance system shows that extractions were not observed after periodontal treatment in the majority of cases. Although periodontitis is a chronic disease, patients suffering from periodontitis have a considerable chance to prevent further tooth loss.

Clinical Fit of Monolithic Zirconia Single Crowns.

PURPOSE: To analyze the clinical fit of monolithic zirconia single crowns (MZSCs) in a prospective cohort study. MATERIALS AND METHODS: A total of 30 posterior teeth were restored with MZSCs. Silicone replicas were made to measure the clinical fit using a stereomicroscope. Measurements were conducted at 17 points per crown at the marginal and occlusal surfaces. RESULTS: The mean clinical fit was 0.104 mm at the crown margin and 0.101 mm at the occlusal surface. Measured distances at the marginal and occlusal surfaces were comparable. CONCLUSION: MZSCs showed acceptable clinical fit.

The single mandibular implant study - Short-term effects of the loading protocol on Oral Health-related Quality of Life.

PURPOSE: A single implant can be placed to retain an overdenture in the edentulous mandible. This study aimed at the development of Oral Health-related Quality of Life comparing immediate and delayed implant loading, i.e., loading after 3 months of submerged healing. METHODS: In a randomized controlled trial, 158 participants received a single mandibular implant in the midline. Quality of life was measured using the summary score of the German 49-item Oral Health Impact Profile at baseline, one month after implant placement (direct loading group) as well as one and four months after loading. RESULTS: Mean scores at baseline were comparable. Four months after implantation, a decrease of mean scores was recognized for both groups, indicating a significantly enhanced quality of life after treatment. When comparing the groups after both 1 and 4 months of loading, quality of life was insignificantly higher in the delayed loading group (1 month: 42.1 vs. 32.3; 4 months: 33.6 vs. 27.7). For immediate loading, an insignificant tendency to an earlier improvement was recognized (Δ1month-baseline: 9.7, compared to Δ1month-baseline: 6.4). CONCLUSIONS: The single mandibular implant concept was associated with a positive impact on quality of life. However, no statistically significant influence of implant loading on quality of life was found.

Four-year outcomes of restored posterior tooth surfaces-a massive data analysis.

OBJECTIVES: There is only sparse knowledge concerning the outcomes of treatments with posterior permanent restorations in general practice settings. This study aimed at evaluating outcomes based on a large dataset by using a novel approach on a tooth surface basis. MATERIALS AND METHODS: The study based on routine data from a major German national health insurance company. Respective treatment fee codes allowed for tracking the clinical courses on a tooth surface level. The study intervention was defined as the placement of a restoration on an interproximal or occlusal posterior tooth surface regardless of its actual extension and material on which no information was available. All surfaces restored between January 1st, 2010 and December 31st, 2013 were included. Kaplan-Meier survival analyses were conducted to estimate four-year survival. The primary outcome was a restorative re-intervention on the same tooth surface. Separate analyses were performed for the secondary outcomes "crowning" and "extraction". RESULTS: Over ten million interproximal surfaces and eight million occlusal surfaces in nine million posterior teeth had been restored. At 4 years, the cumulative survival rates concerning the primary outcome "re-intervention" for mesial surfaces (81.4%; CI 81.3-81.5%) and distal surfaces (81.2%; CI 81.1-81.2%) differed significantly from those for occlusal surfaces (77.0%; CI 76.9-77.0%). Restored surfaces in premolars showed significantly higher survival rates compared to molars. Four-year survival rates for the secondary outcome "crowning" were 91.9% (CI 91.8-91.9%) for mesial surfaces, 92.1% (CI 92.1-92.2%) for distal surfaces and 93.3% (CI 93.2-93.3%) for occlusal surfaces. The respective rates for the secondary outcome "extraction" were 94.5% (CI 94.5-94.5%) for mesial surfaces, 94.8% (CI 94.7-94.8%) for distal surfaces and 95.4% (CI 95.4-95.5%) for occlusal surfaces. CONCLUSIONS: Re-interventions after restorative treatment play a significant role in general practice settings. Surface-related survival rates of restorations reveal a need for improvement. CLINICAL RELEVANCE: This study allows the estimation of the probability of re-interventions after restoring posterior tooth surfaces. It is based on several million cases from general practises under the terms and conditions of a national health insurance system.

Re-interventions after restoring teeth-Mining an insurance database.

OBJECTIVES: The aim of this study was to examine re-interventions after restorative treatment. METHODS: The data was collected from the digital database of a major German national health insurance company. Only permanent teeth were observed. Placing a permanent restoration other than a crown regardless of involved surfaces and material was the study intervention. The data did not allow for a differentiation between fillings and inlays that were estimated only a very small portion of the restorations. Success was defined as not undergoing any restorative re-intervention with fillings or inlays on the same tooth (primary outcome) and assessed with Kaplan-Meier survival analyses over four years. An additional analysis was conducted rating "crowning" and "extraction" of respective teeth as target events. Differences were tested with the Log-Rank-test. A multivariate Cox regression analyses was carried out. RESULTS: A total of 17,024,344 restorations placed in 4,825,408 anterior teeth and 9,973,177 posterior teeth could be traced. Focussing on the primary outcome re-intervention, the cumulative four-year success rate was 69.9% for one surface restorations, 74.8% for two surface restorations, 66.6% for three surface restorations and 61.0% for four surface and more extended restorations. These differences were significant (p<0.0001). Focussing on all three target events re-intervention, crowning and extraction, the cumulative four-year success rate was 66.1% for one surface restorations, 67.5% for two surface restorations, 63.0% for three surface restorations and 55.8% for four surface and more extended restorations. The number of restoration surfaces as well as the tooth position remained significant in the multivariate Cox regression. CONCLUSIONS: The sustainability of restorative dental treatment under the terms and conditions of the German national health insurance system shows room for improvement. From a public health perspective, special focus should be laid on primary and secondary prevention to minimize the restorative treatment need. CLINICAL SIGNIFICANCE STATEMENT: This study shows that re-interventions are observed regularly after restorative treatment. Therefore, preventive and restorative strategies should be revisited and optimised.

Oral Health and Quality of Life in Old Age: A Cross-Sectional Pilot Project in Germany and Poland.

BACKGROUND: The process of ageing influences all dimensions of social life and personal well-being, but the influence of health on different dimensions of quality of life (QoL) among the elderly is rarely examined. OBJECTIVES: The aim of the pilot study is to test the feasibility of a comprehensive study design to evaluate general and dental health as well as QoL in a bi-national sample. In addition, this pilot study should allow for the exploration of potential interactions between QoL, socioeconomic, health and oral health variables. MATERIAL AND METHODS: Individuals aged 64 years and older (n = 100) from university dental clinics of the Wroclaw Medical University, Poland (n = 50) and of the University Hospital in Dresden, Germany (n = 50) were examined. The oral health status of participants was assessed by clinical examination. Socio-demographic, environmental and general health status were evaluated during the medical interview. General quality of life (GQoL) was assessed by an overall question with a visual analogue scale (VAS) from -5 (worst) to +5 (best). Health-related quality of life (HRQoL) and oral health-related quality of life (OHRQoL) were measured with the EQ-5D and OHIP-14 questionnaires. Statistical analyses comprised Pearson's c2 test, Wilcoxon test, linear regression model for statistical analysis and different multivariate linear regression analyses. RESULTS: For the GQoL-VAS-Score the results for QoL measurements were 1.22 ± 2.62 (x± SD), for EQ-5D-Score 7.45 ± 2.25 (x± SD), and for OHIP-14-ADD-Score 11.04 ± 13.56 (x± SD). Differences between Polish and German populations were observed. CONCLUSIONS: The study design proved to be feasible for a senior population. The overall GQoL question, EQ-5D and OHIP-14 were regarded as appropriate instruments. Subjective and objective (oral) health measures showed differences between Germany and Poland. For methodological reasons, these differences are not generalizable, but of value for study hypotheses in larger samples.

Investigation of the Association Between Cement Retention and Prevalent Peri-Implant Diseases: A Cross-Sectional Study.

BACKGROUND: The aim of this study is to examine the association between retention type (cement-retained versus screw-retained restorations) and prevalence of peri-implant diseases in a German university-treated population. METHODS: Data were analyzed from individuals that underwent clinical and radiographic peri-implant examinations as part of a university-based cross-sectional study from September 2011 to October 2012. RESULTS: Data from 139 individuals (mean age: 57.59 years) having 394 implants were analyzed: 192 implants supporting single crowns and 202 fixed partial dentures. Overall, 11.9% of the participants had peri-implantitis, whereas 68.9% had peri-implant mucositis. Crude odds ratios (95% confidence intervals) for peri-implantitis and peri-implant mucositis for cement- versus screw-retained restorations were 1.43 (0.45, 4.60) and 0.89 (0.53, 1.48), respectively. Results remained non-significant in multivariable models adjusting for type of restoration and smoking (all P values >0.50). There was also no effect of splinting restorations on disease prevalence in adjusted analyses (P values >0.32). CONCLUSIONS: In this university-treated sample, there is no association between the type of prosthesis retention and peri-implant diseases. Current findings show that, when appropriate selection and removal of cement is performed, cement retention is not a risk indicator for peri-implant diseases.

Three-year outcomes of apicectomy (apicoectomy): Mining an insurance database.

OBJECTIVES: The outcome of apicectomy in clinical reality is supposed to be different compared to outcomes reported from clinical trials. The objective of this study was to measure the outcome of apicectomies under practice conditions by mining an insurance data base. METHODS: This retrospective study was based on claims data of a major German national health insurance company (BARMER GEK). Through the company's data warehouse fee codes and treatment dates were accessible and allowed the tracing of clinical courses. Kaplan-Meier survival analyses for the target event 'extraction' were conducted for all teeth that underwent apicectomies within a 3 year period. Testing for differences among survival rates across groups was performed with the Log-Rank-test. RESULTS: A total of 93,797 teeth in 77,636 patients could be traced after apicectomy. The cumulative 3-year survival rate was 81.6%. Anterior teeth showed a significantly higher survival rate of 84.0% compared to premolars (80.4%) and molars (80.2%). The survival rate in men (83.5%) was significantly higher than in women (80.6%). Analysis of survival by age revealed continuously declining survival rates with age (93.3% for subjects under 18 years of age to 75.6% for subjects over 84 years of age). CONCLUSIONS: The 3-year outcomes of apicectomy were still acceptable for an intervention that is mostly conducted as a retreatment after failure of a preceding measure. However at a population level, the question remains to be answered whether other treatment options would potentially be more effective.

Survival of teeth treated with cast post and cores: A retrospective analysis over an observation period of up to 19.5 years.

STATEMENT OF PROBLEM: Scientific data about the long-term survival of teeth treated with cast post and cores are scarce. Retrospective studies often use different target events for their analyses. A comparison is therefore complicated. For associated tooth-, jaw-, and patient-related factors little evidence exists as to their effect on survival. PURPOSE: The purpose of this study was to extend the knowledge on the survival of teeth treated with cast post and cores for observation periods of more than 10 years. A decrease or increase in survival times according to the presence or absence of associated parameters needs to be evaluated. MATERIAL AND METHODS: A retrospective evaluation was conducted of all cast post and cores inserted in 1 university clinic between January 1992 and June 2011. A Kaplan-Meier survival analysis was carried out by using extraction as the target event. The survival curves for different tooth types, the presence or absence of adjacent teeth, and the prosthetic restoration of the respective jaws were compared by using the log-rank test (α=.05). A Cox regression model was calculated for multivariate analyses. RESULTS: A total of 717 cast post and cores for 343 patients were recorded. The mean survival time was 13.5 years. A statistically significant decrease in survival times was found for canines (11.9 years) and premolars (13.4 years) versus molars (14.1 years), no adjacent teeth (10.6 years) versus at least 1 adjacent tooth (13.8 years), and the restoration with removable dental prostheses (12.5 years) versus fixed dental prostheses and single crowns (13.9 years). The largest reduction in survival time was found for teeth being used as an abutment for a double crown-retained removable partial dental prosthesis (telescopic denture) (9.8 years). Tooth type and adjacent tooth status remained as significant variables within the multivariate Cox regression model. CONCLUSIONS: Cast post and cores have an acceptable long-term survival time. Because different factors may influence survival, considering these factors in treatment planning may increase the long-term success of these restorations.

Three-year outcomes of root canal treatment: Mining an insurance database.

OBJECTIVES: There is doubt whether success rates of root canal treatments reported from clinical trials are achievable outside of standardized study populations. The aim of this study was to analyse the outcome of a large number of root canal treatments conducted in general practice. METHODS: The data was collected from the digital database of a major German national health insurance company. All teeth with complete treatment data were included. Only patients who had been insurance members for the whole 3-year period from 2010 to 2012 were eligible. Kaplan-Meier survival analyses were conducted based on completed root canal treatments. Target events were re-interventions as (1) retreatment of the root canal treatment, (2) apical root resection (apicoectomy) and (3) extraction. The influences of vitality status and root numbers on survival were tested with the log-rank test. RESULTS: A total of 556,067 root canal treatments were included. The cumulative overall survival rate for all target events combined was 84.3% for 3 years. The survival rate for nonvital teeth (82.6%) was significantly lower than for vital teeth (85.6%; p<0.001). The survival rate for single rooted teeth (83.4%) was significantly lower than for multi-rooted teeth (85.5%; p<0.001). The most frequent target event was extraction followed by apical root resection and retreatment. CONCLUSIONS: Based on these 3-year outcomes, root canal treatment is considered a reliable treatment in practice routine under the conditions of the German national health insurance system. CLINICAL SIGNIFICANCE: Root canal treatment can be considered as a reliable treatment option suitable to salvage most of the affected teeth. This statement applies to treatments that in the vast majority of cases were delivered by general practitioners under the terms and conditions of a nationwide health insurance system.