Clinical evaluation of a posterior composite 10-year report

A 23-Year Observational Follow-Up Clinical Evaluation of Direct Posterior Composite Restorations

The purpose of this observational follow-up clinical study was to observe the quality of posterior composite restorations more than 23 years after application. A total of 22 patients, 13 male and 9 female (mean age 66.1 years, range 50–84), with a total of 42 restorations attended the first and second follow-up examinations. The restorations were examined by one operator using modified FDI criteria. Statistical analysis was performed with the Wilcoxon Mann–Whitney U test and Wilcoxon exact matched-pairs test with a significance level of p = 0.05. Bonferroni–Holm with an adjusted significance level of alpha = 0.05 was applied. With the exception of approximal anatomical form, significantly worse scores were seen for six out of seven criteria at the second follow-up evaluation. There was no significant difference in the first and second follow-up evaluations in the grades of the restorations with regard to having been placed in the maxilla or mandible, as well as for one-surface or multiple-surface restorations. The approximal anatomical form showed significantly worse grades at the second follow-up when having been placed in molars. In conclusion, the study results show that significant differences regarding FDI criteria in posterior composite restorations occur after more than 23 years of service. Further studies with extended follow-up time and at regular and short time intervals are recommended.

The Influence of Low-Molecular-Weight Monomers (TEGDMA, HDDMA, HEMA) on the Properties of Selected Matrices and Composites Based on Bis-GMA and UDMA

Bisphenol A-glycidyl methacrylate (bis-GMA) and urethane dimethacrylate (UDMA) are usually combined with low-viscosity monomers to obtain more desirable viscosity, handling characteristics and general properties. The present study determined the flexural strength (FS), flexural modulus (FM), diametral tensile strength (DTS), and hardness (HV) of five matrices and composites based on these resins. The polymerization shrinkage stress (PSS) was also studied for the composites. The polymer matrices were formed using bis-GMA and UDMA. TEGDMA, HEMA and HDDMA acted as co-monomers. The composites had 45 wt.% of filler content. The highest FS and FM were obtained from the UDMA/bis-GMA/TEGDMA/HEMA matrix and the composite (matrix + filler). The best DTS values were obtained from the UDMA/bis-GMA/HEMA matrix and the composite. One of the lowest values of FS, FM, and DTS was obtained from the UDMA/bis-GMA/HDDMA matrix and the composite. All the composites demonstrated similar hardness values. The lowest polymerization shrinkage stress was observed for the UDMA/bis-GMA/TEGDMA/HEMA composite, and the highest PSS was observed for the UDMA/bis-GMA/TEGDMA/HDDMA composite. The addition of HEMA had a positive effect on the properties of the tested materials, which may be related to the improved mobility of the bis-GMA and UDMA monomers.

Compliance of randomized controlled trials in posterior restorations with the CONSORT statement: a systematic review of methodology

OBJECTIVES

This study aims to investigate the compliance of randomized controlled trials (RCTs) in posterior restorations with the Consolidated Standards of Reporting Trials Statement (CONSORT) statement and to analyze the risk of bias (RoB) of these studies.

METHODS

A systematic search was performed in PubMed, Scopus, Web of Science, LILACS/BBO, and Cochrane Library. Only RCTs published in peer-reviewed journals were included. The compliance with the CONSORT was evaluated in a 0-2 scale where 0 = no description, 1 = poor description and 2 = adequate description. Descriptive analyses of the CONSORT mean score by journal, country, and RoB were performed. The RoB in RCTs was evaluated by using the Cochrane Collaboration's tool version 1.0.

RESULTS

A total of 15,476 studies were identified after duplicates removal. O only 202 meet the eligibility criteria, among which 31 were follow-up studies. Concerning the overall RoB, only 29 out of 171 were classified as low risk of bias. The overall mean CONSORT score was 19 ± 5.4 points, which means compliance of approximately 59%. Significant differences among countries, publication period, and RoB were observed (p < 0.001). The journal's impact factor was not correlated with the overall CONSORT score (p = 0.36).

CONCLUSIONS

The adherence of RCTs conducted in posterior restorations to the CONSORT Statement is still low. In addition, most studies were classified as at unclear risk of bias. These results call up an urgent need for improvement.

CLINICAL RELEVANCE

Most RCTs conducted in posterior teeth have poor reporting and are mainly classified as having an unclear risk of bias.

Rubber dam isolation for restorative treatment in dental patients

BACKGROUND

The effective control of moisture and microbes is necessary for the success of restoration procedures. The rubber dam, as an isolation method, has been widely used in dental restorative treatments. The effects of rubber dam usage on the longevity and quality of dental restorations still require evidence-based discussion. This review compares the effects of rubber dam with other isolation methods in dental restorative treatments. This is an update of the Cochrane Review first published in 2016.

OBJECTIVES

To assess the effects of rubber dam isolation compared with other types of isolation used for direct and indirect restorative treatments in dental patients.

SEARCH METHODS

Cochrane Oral Health's Information specialist searched the following electronic databases: Cochrane Oral Health's Trials Register (searched 13 January 2021), Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 12) in the Cochrane Library (searched 13 January 2021), MEDLINE Ovid (1946 to 13 January 2021), Embase Ovid (1980 to 13 January 2021), LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 13 January 2021), and SciELO BIREME Virtual Health Library (1998 to 13 January 2021). We also searched Chinese BioMedical Literature Database (CBM, in Chinese) (1978 to 13 January 2021), VIP database (in Chinese) (1989 to 13 January 2021), and China National Knowledge Infrastructure (CNKI, in Chinese) (1994 to 13 January 2021). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform, OpenGrey, and Sciencepaper Online (in Chinese) for ongoing trials. There were no restrictions on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (including split-mouth trials) over one month in length assessing the effects of rubber dam compared with alternative isolation methods for dental restorative treatments.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the results of the electronic searches, extracted data, and assessed the risk of bias of the included studies. Disagreement was resolved by discussion. We strictly followed Cochrane's statistical guidelines and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included six studies conducted worldwide between 2010 and 2015 involving a total of 1342 participants (of which 233 participants were lost to follow-up). All the included studies were at high risk of bias. Five studies compared rubber dam with traditional cotton rolls isolation. One study was excluded from the analysis due to inconsistencies in the presented data. Of the four remaining trials, three reported survival rates of the restorations with a minimum follow-up of six months. Pooled results from two studies involving 192 participants indicated that the use of rubber dam isolation may increase the survival rates of direct composite restorations of non-carious cervical lesions (NCCLs) at six months (odds ratio (OR) 2.29, 95% confidence interval (CI) 1.05 to 4.99; low-certainty evidence). However, the use of rubber dam in NCCLs composite restorations may have little to no effect on the survival rates of the restorations compared to cotton rolls at 12 months (OR 1.38, 95% CI 0.45 to 4.28; 1 study, 30 participants; very low-certainty evidence) and at 18 months (OR 1.00, 95% CI 0.45 to 2.25; 1 study, 30 participants; very low-certainty evidence) but the evidence is very uncertain. At 24 months, the use of rubber dam may decrease the risk of failure of the restorations in children undergoing proximal atraumatic restorative treatment in primary molars but the evidence is very uncertain (hazard ratio (HR) 0.80, 95% CI 0.66 to 0.97; 1 study, 559 participants; very low-certainty evidence). None of the included studies mentioned adverse effects or reported the direct cost of the treatment.

AUTHORS' CONCLUSIONS

This review found some low-certainty evidence that the use of rubber dam in dental direct restorative treatments may lead to a lower failure rate of the restorations compared with cotton roll usage after six months. At other time points, the evidence is very uncertain. Further high-quality research evaluating the effects of rubber dam usage on different types of restorative treatments is required.

Does a new formula have an input in the clinical success of posterior composite restorations? A chat study

OBJECTIVE

To compare the clinical behavior of a universal light-curing, ultra-fine particle hybrid composite and successor of this material in class I and II cavities after 60 months.

MATERIALS AND METHODS

Forty patients (21 females, 19 males) with ages ranging between 18 and 38 years (23.15 ± 5.15) received 80 (13 Cl I and 67 Cl II) resin composite restorations (Charisma/Charisma Classic, Kulzer GmbH) in combination with an etch and rinse adhesive system (Gluma 2Bond) under rubber dam isolation. Two experienced operators performed all the restorations. Restorations were evaluated by the other two examiners according to the FDI criteria at baseline and at 6, 12, 18, 24, 36, 48 and 60 months. Surface characteristics of one restoration selected randomly were examined under a scanning electron microscope (SEM) at each recall. Data were analyzed statistically (p < 0.05).

RESULTS

After 60 months, recall rate was 90%. None of the restorations failed. Three restorations from Charisma and 4 from the Charisma Classic group showed minor surface staining. Twelve Charisma and 14 Charisma Classic restorations were scored as 2 for margin staining. Four restorations from both groups showed minor shade deviations but no significant difference was observed between the two restorative materials for any criteria evaluated after 60 months (p > 0.05). SEM evaluations were in accordance with the clinical findings.

CONCLUSIONS

Both materials exhibited clinically similar and successful performance over the 60-month observation period.

CLINICAL RELEVANCE

A new formulation of resin composite may not always perform better clinical performances.

TRIAL REGISTRATION

ClinicalTrials.gov : NCT02888873.

Ageing of Dental Composites Based on Methacrylate Resins-A Critical Review of the Causes and Method of Assessment

The paper reviews the environmental factors affecting ageing processes, and the degradation of resins, filler, and the filler-matrix interface. It discusses the current methods of testing materials in vitro. A review of literature was conducted with the main sources being PubMed. ScienceDirect, Mendeley, and Google Scholar were used as other resources. Studies were selected based on relevance, with a preference given to recent research. The ageing process is an inherent element of the use of resin composites in the oral environment, which is very complex and changes dynamically. The hydrolysis of dental resins is accelerated by some substances (enzymes, acids). Bonds formed between coupling agent and inorganic filler are prone to hydrolysis. Methods for prediction of long-term behaviour are not included in composite standards. Given the very complex chemical composition of the oral environment, ageing tests based on water can only provide a limited view of the clinical performance of biomaterial. Systems that can reproduce dynamic changes in stress (thermal cycling, fatigue tests) are better able to mimic clinical conditions and could be extremely valuable in predicting dental composite clinical performance. It is essential to identify procedure to determine the ageing process of dental materials.

The Dental Amalgam Phasedown in New Zealand: A 20-year Trend

BACKGROUND AND OBJECTIVES

Information on the choice of material and performance of restorations placed in a dental practice annually is limited. The Minamata Convention on Mercury is likely to affect the use of amalgam worldwide. The objective of this research was to investigate the use of restorative materials at the University of Otago Faculty of Dentistry in New Zealand from 1998 to 2017.

METHODS

Data from the Faculty of Dentistry's database from the years of interest were compiled. These data included information on the characteristics of restorations, including information on the material used and number of surfaces involved for each restoration. The tooth in which each restoration was placed was categorized by arch, tooth type, and deciduous or permanent dentition.

RESULTS

Records identified 227,514 permanent restorations placed from January 1998 to December 2017, of which 91.7% were direct restorations. Among direct restorations, composite resin was the most commonly used material, followed by amalgam, glass ionomer, and compomer. The use of amalgam for direct restorations decreased from 52.3% of direct restorations in 1998 to 7.1% in 2017. A corresponding increase was observed in the use of tooth-colored direct restorations, particularly composites. Among indirect restorations, porcelain fused to metal, gold, and stainless steel (in pediatric applications) were the materials most frequently used.

CONCLUSIONS

Despite having no official policy on reducing the use of dental amalgam, the Faculty of Dentistry is following the global trend in reducing its use, with composite resin now well established as the predominant restorative material used. If the current rate of decline persists unchecked, the Faculty of Dentistry could transition to being amalgam free by 2020, although it seems likely that the characteristics and principles of use of the material (and its removal) will be taught for some time to come. This knowledge is important to planning curriculum changes needed to prepare graduates for clinical practice.

A Retrospective Audit of Dental Treatment Provided to Special Needs Patients under General Anesthesia During a Ten-Year Period

OBJECTIVE

The purpose of this study was to perform a comprehensive audit of dental treatment provided to special needs patients (SNP) under general anesthesia (GA) over a ten-year period.

STUDY DESIGN

Special needs patients who received dental treatment under GA as an in-patient at Queen Mary Hospital, Hong Kong SAR during the time period January 2002 and December 2011 were included in the study. The study population was divided into three groups, based on age (<6years, 6-12 years, >12 years). One-way ANOVA was used to evaluate the effect of "age group" on duration of treatment, post-recovery time, treatment procedures and utilization of different restorative materials. Kappa statistics were used for intra-examiner reliability.

RESULTS

A total of 275 patients (174 males and 101 females) were included in the study. The mean age of the patients at the time they received GA was 12.37±10.18 years. Dental procedures performed were mostly restorative in nature (47%). The >12 years group had significantly shorter treatment duration (p<0.05). No significant difference in post-operative recovery time was observed among the three age groups (p>0.05). The <6 years group received significantly less preventive, but more restorative procedures (p<0.05). Significantly fewer extractions were performed in the 6-12 years group (p<0.05). The use of composite restorations was significantly higher in the <6 years group; while amalgam restorations were more frequently used in the >12 years group (P<0.05). Stainless steel crowns were more frequently employed in SNP under 12 years of age (p<0.05). Intra-examiner reliability was good (k=0.94).

CONCLUSIONS

Most of the dental procedures performed under GA on SNP were restorative procedures. For children less than 6 years of age, had longer treatment time under GA. Composite restorations and stainless steel crowns were more frequently used in the primary dentition and amalgam restorations were more frequently employed in the permanent dentition.

Informatics Systems to Assess and Apply Clinical Research on Dental Restorative Materials

Dental biomaterials are used clinically for one or more of the following purposes: to restore function, to enhance esthetics, and to prevent or arrest demineralization of tooth structure. Studies of the clinical performance of restorations and prostheses made from these materials have generally focused on quality assessment and survival statistics. Data from these studies should provide probabilities of specific treatment outcomes that are useful for practicing dentists. However, the utility of these data is limited by the lack of national and international standards for assessing these clinical outcomes. Standardized approaches toward clinical informatics and treatment-decision analysis are urgently needed to minimize the variability of clinical outcomes reported in publications associated with direct and indirect restorative materials used for dental restorations and prostheses.

Rubber dam isolation for restorative treatment in dental patients

BACKGROUND

Successful restorations in dental patients depend largely on the effective control of moisture and microbes during the procedure. The rubber dam technique has been one of the most widely used isolation methods in dental restorative treatments. The evidence on the effects of rubber dam usage on the longevity of dental restorations is conflicting. Therefore, it is important to summarise the available evidence to determine the effects of this method.

OBJECTIVES

To assess the effects of rubber dam isolation compared with other types of isolation used for direct and indirect restorative treatments in dental patients.

SEARCH METHODS

We searched the following electronic databases: Cochrane Oral Health's Trials Register (searched 17 August 2016), Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 7) in the Cochrane Library (searched 17 August 2016), MEDLINE Ovid (1946 to 17 August 2016), Embase Ovid (1980 to 17 August 2016), LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 17 August 2016), SciELO BIREME Virtual Health Library (1998 to 17 August 2016), Chinese BioMedical Literature Database (CBM, in Chinese) (1978 to 30 August 2016), VIP (in Chinese) (1989 to 30 August 2016), and China National Knowledge Infrastructure (CNKI, in Chinese) (1994 to 30 August 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform, OpenGrey and Sciencepaper Online (in Chinese) for ongoing trials. There were no restrictions on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (including split-mouth trials) assessing the effects of rubber dam isolation for restorative treatments in dental patients.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the results of the electronic searches, extracted data and assessed the risk of bias of the included studies. We resolved disagreement by discussion.

MAIN RESULTS

We included four studies that analysed 1270 participants (among which 233 participants were lost to follow-up). All the included studies were at high risk of bias. We excluded one trial from the analysis due to inconsistencies in the presented data.The results indicated that dental restorations had a significantly higher survival rate in the rubber dam isolation group compared to the cotton roll isolation group at six months in participants receiving composite restorative treatment of non-carious cervical lesions (risk ratio (RR) 1.19, 95% confidence interval (CI) 1.04 to 1.37, very low-quality evidence). It also showed that the rubber dam group had a lower risk of failure at two years in children undergoing proximal atraumatic restorative treatment in primary molars (hazard ratio (HR) 0.80, 95% CI 0.66 to 0.97, very low-quality evidence). One trial reported limited data showing that rubber dam usage during fissure sealing might shorten the treatment time. None of the included studies mentioned adverse effects or reported the direct cost of the treatment, or the level of patient acceptance/satisfaction. There was also no evidence evaluating the effects of rubber dam usage on the quality of the restorations.

AUTHORS' CONCLUSIONS

We found some very low-quality evidence, from single studies, suggesting that rubber dam usage in dental direct restorative treatments may lead to a lower failure rate of the restorations, compared with the failure rate for cotton roll usage. Further high quality research evaluating the effects of rubber dam usage on different types of restorative treatments is required.

Ten-Year Survival of Class II Restorations Placed by General Practitioners

The aim of this retrospective practice-based study was to investigate the survival of direct class II restorations placed by a group of general dental practitioners (GDPs) and to analyze the effect of practice-, patient-, and tooth/restoration-related factors. Electronic patient files of 24 general dental practices were used for collecting the data for this study. From the patient files, survival rates of 222,836 composites, amalgams, glass ionomers, and compomers placed in 61,121 patients by 67 GDPs between 1999 and 2011 were analyzed by Kaplan-Meier statistics and a multiple Cox regression. The investigated group of GDPs placed restorations with a satisfactory survival (mean AFR₁₀, 4.9%; 95% confidence interval, 2.1 to 7.7), although a wide variation in annual failure rate (AFR) existed between the different operators, varying between 2.6% and 7.0%. Restorations placed in young adults (21-30 y old) survived longest, whereas they showed a shorter survival in children (hazard ratio [HR], 1.553) and the elderly (HR, 1.593). Restorations in molar teeth, restorations placed in endodontically treated teeth, and multisurface restorations are more at risk for reintervention. However, restoration size (included surfaces) has a greater impact on restoration survival in premolar teeth. For the future, improved data collection at the practice/operator, patient, and tooth/restoration level (e.g., risk assessment and diagnoses) will provide the opportunity to evaluate even more extensively the risk factors involved. Knowledge Transfer Statement: The results of this study give insight into the long-term survival of direct dental restorations and the influencing practice-, patient-, and tooth/restoration-related variables.

A randomized controlled 27 years follow up of three resin composites in Class II restorations

OBJECTIVE

To evaluate the durability of three conventional resin composites in Class II restorations during 27 years.

METHODS

Thirty participants, 25 female and 5 male (mean age 38.2 years, range 25-63), received at least three (one set) as similar as possible Class II restorations of moderate size. The three cavities were chosen at random to be restored with a chemical-cured (Clearfil Posterior) and two visible light-cured resin composites (Adaptic II, Occlusin). A chemical-cured enamel bonding agent (Clearfil New Bond) was applied after Ca(OH)2 covering of dentin and enamel etch. Marginal sealing of the restorations was performed after finishing. One operator placed 99 restorations (33 sets). Evaluation was performed with slightly modified USPHS criteria at baseline, 2, 3, 10 and 27 years.

RESULTS

Postoperative sensitivity was observed in 5 patients. Three participants with 11 restorations (11%) could not be evaluated at the 27 year recall. Thirty-seven restorations failed (13 AII, 10 CP and 14 O). The overall success rate after 27 years was 56.5% (AII 55.2%, CP 63.0%, O 51.7%; p=0.70), with an annual failure rate of 1.6%. The main reason for failure was secondary caries (54.1%), followed by occlusal wear (21.6%) and material fracture (18.9%). Non-acceptable color match was seen in 24 (28.3%) of the restorations (AII 2, CP 16, O 6). Cox regression-analysis showed significant influence of the covariates tooth type, caries risk, and bruxing activity of the participants.

CONCLUSIONS

Class II restorations of the three conventional resin composites showed an acceptable success rate during the 27 year evaluation.

Longevity of posterior composite restorations: a systematic review and meta-analysis

The aim of this meta-analysis, based on individual participant data from several studies, was to investigate the influence of patient-, materials-, and tooth-related variables on the survival of posterior resin composite restorations. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a search resulting in 12 longitudinal studies of direct posterior resin composite restorations with at least 5 years' follow-up. Original datasets were still available, including placement/failure/censoring of restorations, restored surfaces, materials used, reasons for clinical failure, and caries-risk status. A database including all restorations was constructed, and a multivariate Cox regression method was used to analyze variables of interest [patient (age; gender; caries-risk status), jaw (upper; lower), number of restored surfaces, resin composite and adhesive materials, and use of glass-ionomer cement as base/liner (present or absent)]. The hazard ratios with respective 95% confidence intervals were determined, and annual failure rates were calculated for subgroups. Of all restorations, 2,816 (2,585 Class II and 231 Class I) were included in the analysis, of which 569 failed during the observation period. Main reasons for failure were caries and fracture. The regression analyses showed a significantly higher risk of failure for restorations in high-caries-risk individuals and those with a higher number of restored surfaces.

The Normalized Failure Index: a method for summarizing the results of studies on restoration longevity?

Satisfactory restoration longevity is central to operative dentistry and is the subject of a wide variety of publications. However, combining the results of a number of studies to provide an overview, for example, for a meta-analysis may be problematic because of the heterogeneity of the data, and a high proportion of studies may therefore not be included. It is the purpose of this study to present a means whereby the data from cohort studies may be combined to present a representation of restoration longevity, termed the "Normalized Failure Index."

Patient Risk Factors’ Influence on Survival of Posterior Composites

This practice-based retrospective study evaluated the survival of resin composite restorations in posterior teeth, focusing on the influence of potential patient risk factors. In total, 306 posterior composite restorations placed in 44 adult patients were investigated after 10 to 18 yrs. The history of each restoration was extracted from the dental records, and a clinical evaluation was performed with those still in situ. The patient risk status was assessed for caries and “occlusal-stress” (bruxism-related). Statistical analysis was performed by the Kaplan–Meier method and Cox-regression multivariate analysis. In total, 30% of the restorations failed, of which 82% were found in patients with 1 or 2 risk factors. Secondary caries was the main reason of failure within caries-risk patients, whereas fracture was the main reason in “occlusal-stress-risk” patients. The patient variables gender and age did not significantly affect survival, but risk did ( p < .001). Tooth type ( p < .001), arch ( p = .013), and pulpal vitality ( p = .003) significantly affected restoration survival. Within the limits of this retrospective evaluation, the survival of restorations is affected by patient risk factors, which should be included in survival analyses of restorations.

56-month clinical performance of Class I and II resin composite restorations

OBJECTIVE

This study evaluated the 56-month clinical performance of Class I and II resin composite restorations. Filtek P60 was compared with Filtek Z250, which are both indicated for posterior restorations but differ in terms of handling characteristics. The null hypothesis tested was that there is no difference in the clinical performance of the two resin composites in posterior teeth.

MATERIAL AND METHODS

Thirty-three patients were treated by the same operator, who prepared 48 Class I and 42 Class II cavities, which were restored with Single Bond/Filtek Z250 or Single Bond/Filtek P60 restorative systems. Restorations were evaluated by two independent examiners at baseline and after 56 months, using the modified USPHS criteria. Data were analyzed statistically using Chi-square and Fisher's Exact tests (a=0.05).

RESULTS

After 56 months, 25 patients (31 Class I and 36 Class II) were analyzed. A 3% failure rate occurred due to secondary caries and excessive loss of anatomic form for P60. For both restorative systems, there were no significant differences in secondary caries and postoperative sensitivity. However, significant changes were observed with respect to anatomic form, marginal discoloration, and marginal adaptation. Significant decreases in surface texture were observed exclusively for the Z250 restorations.

CONCLUSIONS

Both restorative systems can be used for posterior restorations and can be expected to perform well in the oral environment.

Reasons for replacement of restorations: dentists' perceptions

OBJECTIVE

This study aimed at evaluating dentists' perceived reasons for replacement of restorations and ascertaining the differences arising from dentists' gender, time since graduation and working sector (salaried vs private).

MATERIALS AND METHODS

A postal questionnaire was sent to a total of 592 working-age general dental practitioners in Finland, 57% (n = 339) responded. The dentists were asked to rank in order of priority the six most common reasons for replacement of composite in the incisors and posterior teeth and amalgam in the posterior tooth from a list of 12 reasons. Ranking order 1 was worth six points and order 6 one point; the non-ranked reasons were equal to zero. Differences in the means of the summed scores of caries-related (RC), fracture- and failure-related (RF) and miscellaneous (RO) groups were evaluated by ANOVA. The level of significance was set at p = 0.05.

RESULTS

For each of three restorations, the RF group comprised 48-56% of the sum-scores. Of the single reasons, secondary caries predominated (20-24%). For composite restorations in the incisors, the mean sum-score of the RO group was greater for private-sector dentists (p = 0.04). For composite restorations in the posterior teeth, the mean sum-score of RF group was higher for male than female dentists (p = 0.009). For amalgam, mean score for RF was 10.2, followed by RC (8.5) and RO (1.1).

CONCLUSION

Secondary caries and various fractures and failures predominate as dentists' perceived reasons for replacement of restorations. Private dentists included miscellaneous reasons as one of their six reasons more often than did the salaried dentists. The complex process of treatment planning and decision-making is influenced by many as of yet unknown factors, calling for emphasis on investigating of perceptions.

Preliminary clinical evaluation of short fiber-reinforced composite resin in posterior teeth: 12-months report

This preliminary clinical trial evaluated 12 month clinical performance of novel filling composite resin system which combines short fiber-reinforced composite resin and conventional particulate filler composite resin in high stress bearing applications. A total of 37 class I and II restorations (compound and complex type) were placed in 6 premolars and 31 molars. The restorations were reviewed clinically at 6 months (baseline) and 12 months using modified USPHS codes change criteria for marginal adaptation, post-operative sensitivity, pulpal pain and secondary caries criteria. Photographs and x-rays were obtained for restorative analysis. Results of 12 months evaluation showed 5 restorations having little marginal leakage (B score) and 1 patient had minor pulpal symptom and post-operative sensitivity (B score). No secondary caries or bulk fracture was detected. The majority of restorations exhibited A scores of the evaluated criteria. After 12 months, restorations combining base of short fiber reinforced composite resin as substructure and surface layer of hybrid composite resin displayed promising performance in high load bearing areas.

A review of the developments of self-etching primers and adhesives -Effects of acidic adhesive monomers and polymerization initiators on bonding to ground, smear layer-covered teeth

This paper reviews the developments of self-etching primers and adhesives, with a special focus on the effect of acidic adhesive monomers and polymerization initiators on bonding to ground, smear layer-covered teeth. Ionized acidic adhesive monomers chemically interact with tooth substrates and facilitate good bonding to ground dentin. Polymerization initiators in self-etching primers further promote effective bonding to ground dentin. To promote bonding to both dentin and enamel, phosphonic acid monomers such as 6-methacryloyloxyhexyl phosphonoacetate (6-MHPA) were developed. These novel adhesive monomers also have a water-soluble nature and are hence endowed with sufficient demineralization capability. A new single-bottle, self-etching, 2-hydroxyethyl methacrylate (HEMA)-free adhesive comprising 6-MHPA and 4-acryloyloxyethoxycarbonylphthalic acid (4-AET) was developed. This novel adhesive enabled strong adhesion to both ground enamel and dentin, but its formulation stability was influenced by pH value of the adhesive. To develop hydrolytically stable, single-bottle, self-etching adhesives, hydrolytically stable, radical-polymerizable acidic monomers with amide or ether linkages have been developed.

22-Year clinical evaluation of the performance of two posterior composites with different filler characteristics

OBJECTIVES

This retrospective longitudinal study investigated the longevity of posterior restorations placed in a single general practice using 2 different composites in filler characteristics and material properties: P-50 APC (3M ESPE) with 70vol.% inorganic filler loading (midfilled) and Herculite XR (Kerr) with 55vol.% filler loading (minifilled).

METHODS

Patient records were used for collecting data. Patients with at least 2 posterior composite restorations placed between 1986 and 1990, and still in the practice for regular check-up visits, were selected. 61 patients (20 male, 41 female, age 31.2-65.1) presenting 362 restorations (121 Class I, 241 Class II) placed using a closed sandwich technique were evaluated by 2 operators using the FDI criteria. Data were analyzed with Fisher's exact test, Kaplan-Meier statistics, and Cox regression analysis (p<0.05).

RESULTS

110 failures were detected. Similar survival rates for both composites were observed considering the full period of observation; better performance for the midfilled was detected considering the last 12 years. There was higher probability of failure in molars and for multi-surface restorations.

SIGNIFICANCE

Both evaluated composites showed good clinical performance over 22 years with 1.5% (midfilled) and 2.2% (minifilled) annual failure rate. Superior longevity for the higher filler loaded composite (midfilled) was observed in the second part of the observation period with constant annual failure rate between 10 years and 20 years, whereas the minifilled material showed an increase in annual failure rate between 10 years and 20 years, suggesting that physical properties of the composite may have some impact on restoration longevity.

In Vivo and In Vitro Evaluations of Microleakage Around Class I Amalgam and Composite Restorations

The lining of amalgam restorations showed no significant effect on microleakage around restoration margins. In vivo and in vitro evaluations confirmed that microleakage was higher in resin composite restorations than in amalgam.

12-year Survival of Composite vs. Amalgam Restorations

Information about the long-term clinical survival of large amalgam and composite restorations is still lacking. This retrospective study compares the longevity of three- and four-/five-surface amalgam and composite restorations relative to patients’ caries risk. Patient records from a general practice were used for data collection. We evaluated 1949 large class II restorations (1202 amalgam/747 composite). Dates of placement, replacement, and failure were recorded, and caries risk of patients was assessed. Survival was calculated from Kaplan-Meier statistics. After 12 years, 293 amalgam and 114 composite restorations had failed. Large composite restorations showed a higher survival in the combined population and in the low-risk group. For three-surface restorations in high-risk patients, amalgam showed better survival.

Qualitative and quantitative radiographic assessment of sealed carious dentin: a 10-year prospective study

OBJECTIVE

The objective of this study was to assess radiographic outcomes after partial carious dentin removal performed in deep caries lesions over a 10-year period.

STUDY DESIGN

Baseline image was compared to 3 follow-up radiographs (at 6-7 months, 3 years, and 10 years). Tertiary dentin deposition and lesion depth were qualitatively assessed. Radiographic density changes in the radiolucent zone (RZ) beneath the restoration were quantitatively compared to the control areas (CA) using digital subtraction radiography (Friedman repeated-measures analysis of variance).

RESULTS

A total of 13 teeth were evaluated. In most cases, lesion depth remained unchanged or decreased (12/13) and tertiary dentin formation was observed (10/13) after the 10-year follow-up. Differences between RZ and CA at the 6- to 7-month and 3-year follow-up periods were similar but significantly lower than those at the 10-year assessment.

CONCLUSIONS

Sealing of carious dentin arrested the caries process, promoted deposition of tertiary dentin, and induced mineral gain in the radiolucent zone.

Is it the end of the road for dental amalgam? A critical review

The longevity of dental restorations is dependent on many factors, including those related to materials, the dentist, and the patient. Dental amalgams have successfully served the profession for over a century. The main reasons for restoration failure are secondary caries, fracture of the bulk of the restoration or of the tooth, and marginal deficiencies and wear. The importance of direct-placement, aesthetic, tooth-colored restorative materials is still increasing. Amalgam restorations are being replaced because of alleged adverse health effects and inferior aesthetic appearance. All alternative restorative materials and procedures, however, have certain limitations. This article will attempt to critically analyse both amalgams and resin based composites, through an evaluation of scientific literature.

Posterior amalgam restorations--usage, regulation, and longevity

The use of dental amalgam has declined, but in most of the world, amalgam is the most widely used and widely taught direct restorative material for load-bearing posterior restorations. There are few national regulations on the use of amalgam; however, there are several nations where few amalgam restorations are placed. Long-term studies have shown that under optimum conditions, posterior restorations of amalgam and resin composite last longer than reported previously and that amalgam restorations outlast composite restorations. In general practice settings, posterior amalgam and composite restorations both have lower longevities.

Degradation, fatigue, and failure of resin dental composite materials

The intent of this article is to review the numerous factors that affect the mechanical properties of particle- or fiber-filler-containing indirect dental resin composite materials. The focus will be on the effects of degradation due to aging in different media, mainly water and water and ethanol, cyclic loading, and mixed-mode loading on flexure strength and fracture toughness. Several selected papers will be examined in detail with respect to mixed and cyclic loading, and 3D tomography with multi-axial compression specimens. The main cause of failure, for most dental resin composites, is the breakdown of the resin matrix and/or the interface between the filler and the resin matrix. In clinical studies, it appears that failure in the first 5 years is a restoration issue (technique or material selection); after that time period, failure most often results from secondary decay.

Survival and reasons for failure of amalgam versus composite posterior restorations placed in a randomized clinical trial

BACKGROUND

Failure of dental restorations is a major concern in dental practice. Replacement of failed restorations constitutes the majority of operative work. Clinicians should be aware of the longevity of, and likely reasons for the failure of, direct posterior restorations. In a long-term, randomized clinical trial, the authors compared the longevity of amalgam and composite. SUBJECTS, METHODS AND MATERIALS: The authors randomly assigned one-half of the 472 subjects, whose age ranged from 8 through 12 years, to receive amalgam restorations in posterior teeth and the other one-half to receive resin-based composite restorations. Study dentists saw subjects annually to conduct follow-up oral examinations and take bitewing radiographs. Restorations needing replacement were failures. The dentists recorded differential reasons for restoration failure.

RESULTS

Subjects received a total of 1,748 restorations at baseline, which the authors followed for up to seven years. Overall, 10.1 percent of the baseline restorations failed. The survival rate of the amalgam restorations was 94.4 percent; that of composite restorations was 85.5 percent. Annual failure rates ranged from 0.16 to 2.83 percent for amalgam restorations and from 0.94 to 9.43 percent for composite restorations. Secondary caries was the main reason for failure in both materials. Risk of secondary caries was 3.5 times greater in the composite group.

CONCLUSION

Amalgam restorations performed better than did composite restorations. The difference in performance was accentuated in large restorations and in those with more than three surfaces involved.

CLINICAL IMPLICATIONS

Use of amalgam appears to be preferable to use of composites in multisurface restorations of large posterior teeth if longevity is the primary criterion in material selection.

Retrospective audit of caries management techniques for children under general anesthesia over an 18-year period

The aim of this study was to review the outcomes of dental treatment under general anesthesia and to analyze the different types of caries management techniques for children in different age groups and time periods. Seven hundred inpatient general anesthetics were administered for 656 children between 1982 and 1999 were included in the analysis. This study concluded that the treatment modality of the caries management techniques varied according to the different age groups. Furthermore, the nature of the treatment changed the relative proportion of restorative procedures increased during the period under investigation.

A retrospective clinical study on longevity of posterior composite and amalgam restorations

OBJECTIVES

The purpose of this study was to evaluate retrospectively the longevity of class I and II amalgam and composite resin restorations placed in a general practice.

METHODS

Patient records of a general practice were used for collecting the data for this study. From the files longevity and reasons for failure of 2867 class I and II amalgam and composite resin restorations placed in 621 patients by two operators between 1990 and 1997 were recorded in 2002.

RESULTS

912 amalgam restorations (502 by operator 1 and 410 by operator 2) and 1955 posterior composite resin restorations (1470 by operator 1 and 485 by operator 2) were placed. One hundred and eighty-two amalgam and 259 posterior composite resin restorations failed during the observation period. The main reasons for failure of the restorations were caries (34%), endodontic treatment (12%) and fracture of the tooth (13%). Life tables calculated from the data reveal a survival for composite resin of 91.7% at 5 years and 82.2% at 10 years. For amalgam the survival is 89.6% at 5 years and 79.2% at 10 years. Cox-regression analysis resulted in a significant effect of the amount of restored surfaces on the survival of the restorations. No significant effect of operator, material as well as combination of material and operator was found.

SIGNIFICANCE

In the investigated general practice, two dentists obtained comparable longevity for amalgam and composite resin restorations.

A clinical evaluation of posterior composite restorations: 17-year findings

OBJECTIVE

Since an increasing number of composite restorations in posterior teeth are placed as a routine, this study was conducted to evaluate long-term survival of these restorations placed in general practice.

METHODS

Patients from a private dental office that received restorations in posterior teeth between 1987 and 1988 with P-50 (3M) or Herculite XR (Kerr) resin composites were selected and invited to participate. Restorations were placed under rubber dam isolation. Dentine walls were covered with glass ionomer cement, and composites were placed according to manufacturer's instructions. Thirty-eight patients agreed to participate and signed an informed consent prior to the evaluation. Two calibrated operators worked independently in the evaluation, using modified USPHS criteria. Survival of restorations or subsets of restorations grouped on the basis of variables (material, tooth, cavity type and size) was determined using Kaplan-Meier survival curves.

RESULTS

Ninety-eight failures were recorded among the 282 restorations providing a crude estimate of 34.8% failures. The survival rate was not significant for material (p=0.92) but was significant between tooth (lower premolars and lower molars, p<0.0001), cavity type (p<0.001) and size (p<0.001). The majority of restorations exhibited A or B scores for the evaluated criteria. The main failure cause was fracture of both composites.

CONCLUSIONS

The clinical performance of posterior resin composite restorations evaluated was acceptable after 17-year evaluation. However, the probability of failure of resin composite restorations in molars, Class II, and large restorations is higher.

Influence of explorer tip diameter in identifying restoration margin discrepancies

OBJECTIVES

Evaluations of the marginal adaptation of restorations in clinical trials rely on subjective assessments by evaluators. The purpose of the present study was to assess the use of dental explorers with different tip diameters to detect simulated marginal discrepancies.

METHODS

Using three devices simulating vertical steps, horizontal gaps, and the combination of vertical and horizontal discrepancies and explorers with five different tip diameters, 10 experienced dental faculty members were asked to identify discrepancies at the boundary between Alfa (replacement unnecessarily) and Bravo (replacement questionable) ratings, according to modified United States Public Health Service criteria.

RESULTS

A significant correlation was found between the tip diameters of the explorers and the Alfa/Bravo boundaries for the horizontal gaps, but not for the vertical steps.

CONCLUSION

It was concluded that the tip diameter of dental explorers had no significant effect on the detection of vertical steps, but had a significant effect on the detection of horizontal gaps. The diagnosis of restoration marginal discrepancies and the rating of marginal adaptation in clinical trials may subsequently be found to be best achieved using techniques other than the probing of restoration margins.

Can a single composite resin serve all purposes?

The consensus view less than a decade ago was that direct posterior composites should be restricted to small restorations, preferably in premolar teeth with little, if any, occlusal function. Major advances in adhesive systems, materials and restorative techniques have combined to allow us to question this view and our increased clinical evidence base makes it appropriate to reconsider this viewpoint.

A synthetic enamel for rapid tooth repair

The conventional treatment of dental caries involves mechanical removal of the affected part and filling of the hole with a resin or metal alloy. But this method is not ideal for tiny early lesions because a disproportionate amount of healthy tooth must be removed to make the alloy or resin stick. Here we describe a dental paste of synthetic enamel that rapidly and seamlessly repairs early caries lesions by nanocrystalline growth, with minimal wastage of the natural enamel.

Five-year clinical performance of posterior resin composite restorations placed by dental students

OBJECTIVES

To investigate the survival over a five-year period of posterior resin composite restorations placed by students.

METHODS

Class I and II resin composite restorations placed by second-fourth year dental students were evaluated. Patients attended the dental school every 6 months for a regular check-up during which all restorations were checked on their clinical acceptability. In case of replacement or repair of a restoration, this was registered in the patient's record. From each record the survival time and reasons for failure of resin composite restorations were gathered.

RESULTS

Seven-hundred three posterior resin composite restorations in 382 patients (49% female and 51% male, age 22-78) were evaluated. At 5 years 560 of the 703 restorations were still considered to be "clinically acceptable". Forty-nine restorations were considered as "functionally present", of which 44 were restored with a crown and four had received a new restoration adjacent to the existing restoration without its removal. Ninety-four restorations had failed. The main reasons for failure were restoration fracture, caries, endodontic treatment, defective margin and lack of proximal contact. The survival rate of the restorations was 87% at 5 years, resulting in an annual failure rate of 2.8%.

CONCLUSIONS

Dental students are able to place resin composite restorations in posterior teeth with an acceptable mean annual failure rate.

Dentists' molar restoration choices and longevity: a web-based survey

STATEMENT OF PROBLEM

The increasing trend toward esthetics has led to controversy as to the longevity of esthetic restorations and the wisdom of having traditional restorations replaced for esthetic reasons. With the assumption that the way dentists treat their own teeth may be a good indication of the accumulated wisdom of the profession, knowledge of dentists' own restorative choices may provide guidance in selecting the most appropriate restorations.

PURPOSE

The purpose of this article was to determine restorative choices of dentists for personal molars and estimate restoration longevity.

MATERIAL AND METHODS

Information about dentists' molars was obtained from a Web-based survey designed to receive dentists' demographic data and charting of 8 molar teeth with estimated longevity. Approximately 12,000 e-mails asking to access the website were sent to dentists' addresses randomly selected from a commercial database. Nonrespondents received 1 reminder. The responses were statistically analyzed with a chi-square analysis (alpha=.05).

RESULTS

Seven hundred fifty-seven valid replies provided information for 6,034 teeth (22% unrestored, 75% restored, 2% missing). Restorations reported included amalgam (36%), gold inlay/onlay (13%), complete veneer crown (CVC) (10%), metal-ceramic crown (MCC) (8%), and composite (7%). Other esthetic options accounted for less than 3%. Restorations with more than 20 years longevity included amalgam restorations (58%), gold inlays/onlays (48%) and crowns (23%). Fifty-six percent of esthetic restorations and 5% of amalgams were placed in the last 5 years. The following restorations were placed in the last year (n=186): 38% esthetic, 29% crowns (18% MCC; 11% CVC), and 17% gold inlay/onlay or amalgam. Significant differences (P<.001) were identified for dentist's gender, year of graduation and practice location.

CONCLUSIONS

Most dentists have not replaced traditional metallic restorations with esthetic alternatives. Dentists still choose nonesthetic options for significant numbers of their own restorations.

Marginal adaptation of class II resin composite restorations using incremental and bulk placement techniques: an ESEM study

This in vitro study compared marginal gap formation in class II resin composite restorations. Forty caries-free extracted molars were prepared in a standardized manner for class II restoration by one of four methods: bulk- or incrementally-placed light-activated resin composite (Amelogen), and bulk- or incrementally-placed chemically activated composite (Rapidfill). The restored teeth, after finishing and polishing, and thermocycling, were examined using environmental scanning electron microscopy. Marginal gap measurements at predetermined facial and lingual margin sites showed no significant differences between the two sites within any of the groups. Both the light- and the chemically-activated restorations showed no significant differences in mean marginal gap sizes whether they were placed by incremental or bulk techniques. Amelogen restorations placed by both methods had significantly larger margin gaps than those of each of the Rapidfill groups (P<0.05). Thus, although method of placement of a given material had no significant effect on the quality of marginal adaptation, both of the chemically activated resin composite restorations produced significantly smaller marginal gaps than both the bulk- and incrementally-placed light-activated composites.