Long term clinical performance of 'open sandwich' and 'total-etch' Class II composite resin restorations showing proximal deterioration of glass-ionomer cement.

OBJECTIVES: To compare clinical performance of resin composite posterior Class-II restorations placed with etch-and-rinse adhesive or open sandwich technique using glass-ionomer cement. METHODS: Data on Class II restorations placed by one dentist between 1990 and 2016 were collected from patient files, including caries risk, tooth related variables, applied materials and dates of last check-up visit and restoration placement. Open sandwich restorations were placed before 2001, while after 2001, a total-etch technique using etch-and-rinse 3-step adhesive was used when placing a Class II composite restoration. For statistical analysis, Kaplan-Meier statistics and a multilevel Cox-Regression was conducted (p < 0.05). Annual Failures Rates (AFR) were calculated. RESULTS: 675 Class II restorations were placed in 91 patients, 491 total-etch restorations (observation time 2-18 y), and 184 open sandwich restorations (observation time 19-29 y) showing AFRs at 15 years as 2.9 % for total-etch and 9.7 % for open sandwich restorations. Secondary caries as failure was equally distributed among the 2 groups and 27 % of the failures in the open sandwich group were due to proximal deterioration of glass-ionomer cement. The Cox-regression showed a significant higher risk for failure for the open sandwich technique compared to total-etch class-II composite restorations (HR = 2.9; p < 0.001). SIGNIFICANCE: Application of glass-ionomer cement using the open sandwich technique cannot be recommended for class-II restorations as being more complex and showing poorer clinical performance.

The differences between three performance measures on dental restorations, clinical success, survival and failure: A matter of perspective.

OBJECTIVES: The aim of this retrospective methodology study was to investigate the influence of using different definitions for restoration failure and inclusion criteria on restoration longevity expressed in AFR. METHODS: EPF from fifteen general dental practices were used for collecting the data for this study. From the EPF, 321,749 composite restorations placed in 52,245 patients by forty-seven GDPs between January 2000 and December 2011 were included. Kaplan-Meier statistics were applied and mean AFRs over 2, 5 and 10 years were calculated. The effect on the AFR of using different levels of failure: based on Claims data (CD), Success (SUC), Survival (SUR) and different inclusion criteria of tooth/restoration variables were reported. RESULTS: Highest AFRs were found for level CD, in which every intervention was considered as failure, and the lowest AFRs for level SUR in which repairs and an endodontic treatments were not considered as a failure. AFRs increased when the observation period prolonged especially for SUR, followed by SUC and CD. An overview of long-term survival studies showed a wide variation in study design, performed clinical examination (USPHS criteria or GDP), number of restorations included, description of restoration failure and found AFRs for CD, SUC and SUR. SIGNIFICANCE: Using failure criteria, Success and Survival, in future clinical studies would enable a better comparison of studies as well as demonstrate the impact of more conservative restorative intervention protocols on patient care.

Impact of individual-risk factors on caries treatment performed by general dental practitioners.

OBJECTIVE: This prospective study investigated how individual patient risk factors impacted non-operative and operative treatment decisions in a dental practice-based research network in The Netherlands. METHODS: Data from were collected from 11 dental practices, whose patients visited the practice at least once during the observation period (January 2015 to September 2017). Descriptive analysis was performed, followed by multiple logistic regression. RESULTS: The records of 39,690 patients were analyzed. Approximately one-half of the population (n = 21,056) underwent a restoration procedure during the observation period, of which 5981 (28.4%) were classified with fair oral hygiene, and 5341 (25.4%) with a high risk for caries. The population without restorative intervention (n = 18,634) consisted mainly of patients with good oral health (n = 5132 [27.5%]) and low risk for caries (n = 7792 [41.8%]). A high risk for caries was associated with a greater chance of preventive instruction (odds ratio [OR] 1.60), applications of topical fluoride (OR 1.20) or sealants (OR 1.39), and restorative interventions (OR 5.72). There was wide variation among practices regarding the treatment provided. CONCLUSION: Of the 11 general dental practices that participated in this study, there was a higher chance of patients with a high risk for caries to receive preventive instructions, and professionally applied topical fluoride and sealants in the majority of practices promoting a personalized treatment approach to patients with caries. CLINICAL SIGNIFICANCE: A more personalized treatment approach for patients with caries was associated with a higher prevalence of high caries risk patients in the majority of practices. More studies, however, are needed to investigate whether general dental practitioners consider the assessment of individual patient risk factors in planning personalized treatment strategies.

Minimally Invasive Intervention for Primary Caries Lesions: Are Dentists Implementing This Concept?

Contemporary minimally invasive treatment concepts for restorative treatment of primary caries lesions include both delayed intervention and smaller-sized preparations restricted to removal of carious tissue. The aim of this study was to investigate whether these concepts have resulted in a trend towards a more conservative choice made by dentists regarding treatment thresholds and restorative techniques. The results from previously conducted, precoded questionnaires developed by Espelid and Tveit, as well as from a recent Dutch questionnaire, were collected and analysed. A worldwide trend towards more minimally invasive strategies in the operative treatment of caries lesions could not be observed, neither for the initiation of operative treatment nor for the preparation techniques. However, in some countries, changes over time could be assessed, especially in Norway, where a reduction in the proportion of interventions is visible for both occlusal and approximal lesions, indicating that more dentists are postponing interventions until the lesions have progressed to a deeper level. From the Dutch national survey, it could be concluded that operators that intervene at an earlier stage of approximal lesioning (stage ≤4) also intervene at an earlier stage of occlusal caries (stage ≤3) (p = 0.012; OR = 2.52; 95% CI: 1.22-5.22). Generally, it can be concluded that dentists worldwide still tend to operatively intervene at a too early stage of caries, although variations exist between countries. A worldwide shift could be observed in the restorative material applied, since composite resin has almost completely replaced amalgam for restoring primary caries lesions.

Decision-making of general practitioners on interventions at restorations based on bitewing radiographs.

OBJECTIVE: The aim of this study was to compare decision-making based on bitewing analysis of restored proximal surfaces by general dental practitioners (GDPs) with diagnossis and clinical decisions made by experts in cariology and restorative dentistry. METHODS: This practice-based study used a database of 7 general dental practices. Posterior bitewing radiographs were selected from the electronic patient files of patients, and 770 cases of proximal restored surfaces were selected. Fifty percent of the cases which lead to the restorative decision, and the other half were cases decided for monitoring by the GDPs. Three experts performed radiographic assessment. The outcome variables were agreement of diagnosis and decision of treatment. Cohen's kappa statistic was used. RESULTS: For the experts, moderate to substantial intraexaminer agreement was observed for the diagnostic criteria, and kappa values of 0.77, 0.79, and 0.88 were obtained for each expert regarding the treatment assignment. Agreement between GDPs and the majority of experts for secondary caries varied between 67 and 83%. One hundred seventy-three out of 385 cases that were treated by GDPs were decided for monitoring by the experts, while 8 cases that were decided for monitoring by the GDPs were decided for treatment. The agreement between experts and GDPs was moderate for secondary caries detection, and fair for treatment decision. CONCLUSION: The GDPs tend to have a less conservative approach regarding the decision to intervene or not concerning the reassessment of restorations, showing moderate agreement with the experts for secondary caries detection and fair agreement regarding the treatment decision. CLINICAL SIGNIFICANCE: This study highlights that GDPs tend to have a less conservative approach to the decision to intervene or not in posterior restorations, compared to experts in cariology and restorative dentistry. Efforts should be made to reduce these differences based on minimally invasive dentistry.

A practice based longevity study on single-unit crowns.

OBJECTIVES: This retrospective longitudinal study aimed to assess the longevity of single unit crowns placed by several dentists and to investigate risk factors associated with crown failures. METHODS: From patient files, longevity of 3404 full crown restorations placed in 1557 patients by 8 Dutch dentists between 1996 and 2011 were analyzed. Annual failure rates (AFRs) were calculated and variables associated with failure (success and survival of crowns) were assessed by multivariate Cox-regressions analysis with shared frailty for patients. RESULTS: Most of crowns were PFM (63.8%) placed in molars (58.1%) and non endodontically treated teeth (65.4%). The observation time of restorations varied from 3 weeks to 11 years with a mean of 7 years, resulting in a mean AFR at 11 years of 2.1% and 0.7% for success and survival of crowns, respectively. Among dentists a relevant variation for type of interventions was observed with AFR varying between 1.2% and 3.5%. The most significant risk factor for failure of crowns was the presence of an endodontic treatment, resulting in Hazard ratios of 1.31 for success [95%CI 1.07-1.61] and 1.89 [95%CI 1.35-2.65] for survival of crowns. Tooth type, tooth position (jaw) and gender showed also a significant influence on success of crowns. For survival, increase in patients' age results in a higher risk for failure. CONCLUSIONS: Overall, crowns placed by a selected group of dentist showed a good to acceptable success and survival rates, mainly dependent from the practice. The presence of an endodontically treated tooth was a significant risk factor leading to more failures.

Sealing of restorations with marginal defects does not affect their longevity.

PURPOSE: To evaluate sealed amalgam and resin-based composite restorations after 12 years to determine whether sealing minor defects (micro-repairs) enhanced the longevity of restorations. METHODS: 34 subjects aged 18-80 were recruited. This sample group underwent 137 restorations, including 51 resin-based composite (RC) and 86 amalgam (AM) restorations. Existing restorations with localized, marginal defects were assigned to one of two groups: (a) the Sealing group (n=48, 27 AM; 21 RC) or (b) the Control group (n=89, 59 AM; 30 RC). The quality of each restoration was scored according to the modified USPHS criteria by two examiners at the beginning of the study and after 1-5, 10, and 12 years. Kaplan Meier survival curves were created and a Cox regression was applied to investigate survival variables. Mantel Cox, Wilcoxon, and Friedman tests were performed for comparisons within groups. RESULTS: After 12 years, no statistically significant differences were observed for the variables "restorative material" (P= 0.538) or "sealing yes/no" (P= 0.136) with respect to the longevity of the restorations. All groups behaved similarly with regard to marginal adaptation, secondary caries, and tooth sensitivity (P≥ 0.05). Cumulatively, after a 12-year observation period, sealing minor restoration defects did not affect the longevity of the restorations. CLINICAL SIGNIFICANCE: Sealing minor marginal defects for resin composites or amalgam restorations did not affect their longevity. This intervention may be considered over-treatment for patients with low-to-medium risks for developing dental caries.

Repair may increase survival of direct posterior restorations - A practice based study.

OBJECTIVES: To investigate repairs of direct restorations by a group of Dutch general dental practitioners (GDPs) and its consequences on longevity of restorations. METHODS: Data set was based on dental records of patients attending 11 general dental practices (24 Dentists) in the Netherlands. Patients that received Class II Amalgam or Composite restorations were included in the study. The outcomes were considered in two levels: "Success" - When no intervention was necessary on the original restoration, it was considered clinically acceptable. "Survival" - Repaired restorations were considered clinically acceptable. Kaplan-Meier statistics and Multivariate Cox regression were used to assess restorations longevity and factors associated with failures (p<0.05). RESULTS: 59,722 restorations placed in 21,988 patients were analyzed. There was a wide variation in the amount of repairs among GDPs when a restoration had failed (Level 1). Repairs of multi-surface restorations were more frequent (p<0.001). A total of 9253 restorations (Level 1) or 6897 restorations (Level 2) had failed in a 12-year observation time. "Success" and "Survival" of the restorations reached 65.92% (AFR=4.08%) and 74.61% (AFR=2.88%) at 10 years, respectively. Patient (age, removable denture) and tooth/treatment-related factors (molars, >2 restored surfaces, endodontic treatment, Amalgam) were identified as risk factors for failure (p<0.001). CONCLUSION: Overall, the GDPs showed satisfactory rates of restoration longevity over 10 years. Repair can increase the survival of restorations although, substantial differences exist among practitioners in repair frequency and AFRs. Molars, multi-surface restorations, presence of an endodontic treatment and a removable denture were identified as risk factors for failure. CLINICAL SIGNIFICANCE: Repair, instead of total replacement of a defective restoration, is a Minimally Invasive procedure which can increase the survival of the original filling, reducing the risk for pulp complications and treatment costs.

A practice-based research network on the survival of ceramic inlay/onlay restorations.

OBJECTIVE: To evaluate prospectively the longevity of ceramic inlay/onlay restorations placed in a web-based practice-based research network and to investigate risk factors associated with restoration failures. MATERIALS AND METHODS: Data were collected by a practice-based research network called Ceramic Success Analysis (CSA). 5791 inlay/onlay ceramic restorations were placed in 5523 patients by 167 dentists between 1994 and 2014 in their dental practices. For each restoration specific information related to the tooth, procedures and materials used were recorded. Annual failure rates (AFRs) were calculated and variables associated with failure were assessed by a multivariate Cox-regression analysis with shared frailty. RESULTS: The mean observation time was 3 years (maximum 15 years) of clinical service, and AFRs at 3 and 10 years follow up were calculated as 1.0% and 1.6%. Restorations with cervical outline in dentin showed a 78% higher risk for failure compared to restorations with margins in enamel. The presence of a liner or base of glass-ionomer cement resulted in a risk for failure twice as large as that of restorations without liner or base material. Restorations performed with simplified adhesive systems (2-step etch-and-rinse and 1-step self-etch) presented a risk of failure 142% higher than restorations performed with adhesives with bonding resin as a separate step (3-step etch-and-rinse and 2-step self-etch). 220 failures were recorded and the most predominant reason for failure was fracture of the restoration or tooth (44.5%). CONCLUSIONS: Ceramic inlay/onlay restorations made from several glass ceramic materials and applied by a large number of dentists showed a good survival. Deep cervical cavity outline, presence of a glass ionomer lining cement, and use of simplified adhesive systems were risk factors for survival.

Longevity of direct restorations in Dutch dental practices. Descriptive study out of a practice based research network.

OBJECTIVES: The aim of this retrospective practice-based study was to investigate the longevity of direct restorations placed by a group of general dental practitioners (GDPs) and to explore the effect of practice/operator, patient, and tooth/restoration related factors on restoration survival. METHODS: Electronic Patient Files of 24 general dental practices were used for collecting the data for this study. From the patient files, longevity of 359,548 composite, amalgam, glass-ionomer and compomer placed in 75,556 patients by 67 GDPs between 1996 and 2011 were analyzed. Survival was calculated from Kaplan-Meier statistics. RESULTS: A wide variation in annual failure rate (AFR) exists between the different dental practices varying between 2.3% and 7.9%. Restorations in elderly people (65 years and older, AFR 6.9%) showed a shorter survival compared to restorations placed in patients younger than 65 years old (AFR 4.2%-5.0%). Restorations in molar teeth, multi-surface restorations and restorations placed in endodontically treated teeth seemed to be more at risk for re-intervention. CONCLUSION: The investigated group of GDPs place restorations with a satisfactory longevity (mean AFR 4.6% over 10 years), although substantial differences in outcome between practitioners exist. Several potential risk factors on practice/operator, patient, and tooth/restoration level have been identified and require further multivariate investigation.