Dental cavity liners for Class I and Class II resin-based composite restorations.

BACKGROUND: Resin-based composite (RBC) is currently accepted as a viable material for the restoration of caries for posterior permanent teeth requiring surgical treatment. Despite the fact that the thermal conductivity of the RBC restorative material closely approximates that of natural tooth structure, postoperative hypersensitivity is sometimes still an issue. Dental cavity liners have historically been used to protect the pulp from the toxic effects of some dental restorative materials and to prevent the pain of thermal conductivity by placing an insulating layer between restorative material and the remaining tooth structure. This is an update of the Cochrane Review first published in 2016. OBJECTIVES: The objective of this review was to assess the effects of using dental cavity liners in the placement of Class I and Class II resin-based composite posterior restorations in permanent teeth in children and adults. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 12 November 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 10) in the Cochrane Library (searched 12 November 2018), MEDLINE Ovid (1946 to 12 November 2018), Embase Ovid (1980 to 12 November 2018) and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 12 November 2018). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: We included randomized controlled trials assessing the effects of the use of liners under Class I and Class II posterior resin-based composite restorations in permanent teeth (in both adults and children). We included both parallel and split-mouth designs. DATA COLLECTION AND ANALYSIS: We utilized standard methodological procedures prescribed by Cochrane for data collection and analysis. Two review authors screened the search results and assessed the eligibility of studies for inclusion against the review inclusion criteria. We conducted risk of bias assessments and data extraction independently and in duplicate. Where information was unclear we contacted study authors for clarification. MAIN RESULTS: Eight studies, recruiting over 700 participants, compared the use of dental cavity liners to no liners for Class I and Class II resin-based composite restorations.Seven studies evaluated postoperative hypersensitivity measured by various methods. All studies were at unclear or high risk of bias. There was inconsistent evidence regarding postoperative hypersensitivity (either measured using cold response or patient-reported), with a benefit shown at some, but not all, time points (low-quality evidence).Four trials measured restoration longevity. Two of the studies were judged to be at high risk and two at unclear risk of bias. No difference in restoration failure rates were shown at 1 year follow-up, with no failures reported in either group for three of the four studies; the fourth study had a risk ratio (RR) 1.00 (95% confidence interval (CI) 0.07 to 15.00) (low-quality evidence). Three studies evaluated restoration longevity at 2 years follow-up and, again, no failures were shown in either group.No adverse events were reported in any of the included studies. AUTHORS' CONCLUSIONS: There is inconsistent, low-quality evidence regarding the difference in postoperative hypersensitivity subsequent to placing a dental cavity liner under Class I and Class II posterior resin-based composite restorations in permanent posterior teeth in adults or children 15 years or older. Furthermore, no evidence was found to demonstrate a difference in the longevity of restorations placed with or without dental cavity liners.

A new classification system for the restoration of root filled teeth.

The aim of this report is to (i) review the current literature on the status of root filled teeth, (ii) analyse the most important factors in decision-making, (iii) discuss the current restorative concepts, and (iv) classify both the evidence and clinical practice in a way that seeks to be clear, understandable and helpful for clinicians. Restoration of root filled teeth represents a challenge for the clinician and remains a controversial subject. The guidelines describe a new classification that is drawn from evidence presented in the literature and also from clinical expertise-based reviews. It describes five categories of teeth.

An analysis of the timing and materials associated with pulp disease following restorative dental treatment.

AIM: To assess whether the timing of pulp disease after tooth restoration was associated with type of restorative dental material used, extent of the restoration or tooth type. METHODOLOGY: A comprehensive search and analysis of data using the Titanium Oral Health Management software program at The Oral Health Centre of Western Australia were performed to correlate procedural codes for teeth that had restorations placed and subsequently developed pulp disease requiring endodontic treatment or extraction from 1st January 2009 to 31st December 2013. Manual analysis of paper and/or electronic patient record cards was also performed. Data collected included restoration type, restored tooth surfaces, tooth type and the dates of restoration and subsequent endodontic intervention or extraction. RESULTS: Of 330 teeth that met the inclusion criteria, 84 (26%) had composite resin restorations, 80 (24%) had amalgams, 119 (36%) had glass-ionomer cement (GICs), and 47 (14%) had crowns. The average time between restoration and further intervention was 330 days with a range from 3 to 1775 days (approximately 5 years). Teeth restored with crowns or five-surface restorations were significantly more likely to require earlier intervention than other restorations. Premolar and anterior teeth were also more likely to require earlier intervention. CONCLUSIONS: Teeth that developed pulp disease requiring further intervention that were restored with crowns and five-surface GIC developed the disease sooner than teeth that were restored with amalgam or composite. In teeth with five-surface restorations that developed pulp disease requiring further intervention, premolar and anterior teeth developed the pulp disease sooner than molars.

Dental cavity liners for Class I and Class II resin-based composite restorations.

BACKGROUND: Resin-based composite (RBC) is currently accepted as a viable material for the restoration of caries for posterior permanent teeth requiring surgical treatment. Despite the fact that the thermal conductivity of the RBC restorative material closely approximates that of natural tooth structure, postoperative hypersensitivity is sometimes still an issue. Dental cavity liners have historically been used to protect the pulp from the toxic effects of some dental restorative materials and to prevent the pain of thermal conductivity by placing an insulating layer between restorative material and the remaining tooth structure. OBJECTIVES: The objective of this review was to assess the effects of using dental cavity liners in the placement of Class I and Class II resin-based composite posterior restorations in permanent teeth in children and adults. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 25 May 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 4) in the Cochrane Library (searched 25 May 2016), MEDLINE Ovid (1946 to 25 May 2016), Embase Ovid (1980 to 25 May 2016) and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 25 May 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: We included randomized controlled trials assessing the effects of the use of liners under Class I and Class II posterior resin-based composite restorations in permanent teeth (in both adults and children). We included both parallel and split-mouth designs. DATA COLLECTION AND ANALYSIS: We utilized standard methodological procedures prescribed by Cochrane for data collection and analysis. Two review authors screened the search results and assessed the eligibility of studies for inclusion against the review inclusion criteria. We conducted risk of bias assessments and data extraction independently and in duplicate. Where information was unclear we contacted study authors for clarification. MAIN RESULTS: Eight studies, recruiting over 700 participants, compared the use of dental cavity liners to no liners for Class I and Class II resin-based composite restorations.Seven studies evaluated postoperative hypersensitivity measured by various methods. All studies were at unclear or high risk of bias. There was inconsistent evidence regarding postoperative hypersensitivity (either measured using cold response or patient-reported), with a benefit shown at some, but not all, time points (low-quality evidence).Four trials measured restoration longevity. Two of the studies were judged to be at high risk and two at unclear risk of bias. No difference in restoration failure rates were shown at one year follow-up, with no failures reported in either group for three of the four studies; the fourth study had a risk ratio (RR) 1.00 (95% confidence interval (CI) 0.07 to 15.00) (low-quality evidence). Three studies evaluated restoration longevity at two years follow-up and, again, no failures were shown in either group.No adverse events were reported in any of the included studies. AUTHORS' CONCLUSIONS: There is inconsistent, low-quality evidence regarding the difference in postoperative hypersensitivity subsequent to placing a dental cavity liner under Class I and Class II posterior resin-based composite restorations in permanent posterior teeth in adults or children 15 years or older. Furthermore, no evidence was found to demonstrate a difference in the longevity of restorations placed with or without dental cavity liners.

Evaluation of a novel repetitive gas-enhanced permeation test for restoration leakage determination after thermo-mechanical loading.

OBJECTIVES: To assess leakage of class-I restorations using a gas-enhanced permeation test (GEPT) as compared with conventional SEM or dye analysis. MATERIALS AND METHODS: Pressure differences over time and penetrating water volumes were measured simultaneously in a two-chamber system (GEPT) before and after class I cavity preparation in 30 molars. Ten teeth were restored with a composite restoration without bonding (A1), a composite restoration with bonding (A2) or a ceramic indirect restoration (B). Five intact teeth served as controls (C). Another GEPT measurement was performed and impressions were taken. Teeth were subjected to thermodynamic loading (1 200 000 cycles) and final GEPT measurements and impressions were made. SEM evaluation of the marginal continuity was performed and teeth were subjected to a Fuchsin dye penetration test. Spearman's rank test was used to compare results from different tests. RESULTS: The GEPT and SEM values did not correlate before loading (0.359, p = 0.051), but significantly correlated afterwards (0.662, p < 0.0001). The correlations between the Fuchsin dye penetration test and GEPT and SEM surface marginal analysis were significant (0.777 and 0.534, p-values < 0.0001 and 0.002, respectively). CONCLUSIONS: SEM marginal analysis was mainly limited in reflecting the surface restoration integrity. GEPT evaluation may, therefore, serve as a tool to non-destructively assess restoration sub-surface integrity over time. CLINICAL RELEVANCE: The current study provided proof that restoration margin quality does not necessarily reflect its leakage behaviour.

Comparative evaluation of microleakage of a carbomer/fluoroapatite-enhanced glass-ionomer cement on primary teeth restorations.

AIM: Carbomer cement represents a novel glass-ionomer which gradually mineralises into fluoroapatite. Purpose of this study was to evaluate microleakage around restorations in deciduous teeth made with composite resin, conventional glass-ionomer cement, resin-modified glass-ionomer cement and carbomer/fluoroapatite-enhanced glass-ionomer cement. MATERIALS AND METHODS: A group of 40 primary upper canines, primary upper and lower molars was divided into 4 groups (n=10). Class I cavities were prepared by diamond cylindrical bur at high speed and were restored with a composite resin (Group 1), with a glass- ionomer cement (Group 2), with a resin-modified glass-ionomer cement (Group 3) and with a carbomer/fluoroapatite-enhanced glass- ionomer cement (Group 4). Hard tissue's bonding involved, in the case of composite resin a total etch bonding procedure, and in glass ionomers the use of their respective primers. Restorations were finished and polished. A 24-hour water storage was followed by thermocycling (1500 cycles, 5°C - 36°C - 55°C - 36°C with a dwell time of 15 seconds) and dye penetration test with immersion in 5% methylene blue for 24 hours. In order to assess the degree of microleakage longitudinal cuts were produced by means of a microtome at 0.5 mm and at 1 mm from the restoration margin, and photographs were taken with a stereomicroscope at 100X. Microleakage was classified according to the number of surfaces and the depth at which dye penetration was observed. Data were analysed with ANOVA and post-hoc analysis was performed with Bonferonni test (p<0.05). RESULTS: Statistical analysis exhibited no significant statistical difference between Group 2 and Group 3 (p>0.05). Statistical difference was exhibited between Group 3 and Group 4 (p<0.01), with Group 4 exhibiting lower microleakage values. Group 1 exhibited the lowest mean microleakage values and statistical difference in comparison with all groups (p<0.001). Group 4 exhibited the lowest microleakage values among the cements. CONCLUSION: Superior marginal integrity is achieved in restored primary teeth when composite resin is used. If the clinical case suggests the use of a glass-ionomer cement, carbomer/fluoroapatite-enhanced glass-ionomer cement is prefered in terms of microleakage.

Evaluation of Microleakage of Nanoionomer and Nanocomposite Restorations, immersed in Fruit Drink, Fresh Fruit Juice and Soft Drink--An in vitro Study.

AIM: To evaluate microleakage of Nanoionomer (3M ESPE Ketac(™) N100 Light cured Nanoionomer Restorative) and Nanocomposite (3M ESPE Filtek(™) Z350 XT Universal Restorative) restorations, immersed in fruit drink, fresh fruit juice and soft drink. STUDY DESIGN: Eighty caries free maxillary premolars extracted for orthodontic purpose were used for the study. Class V cavities were prepared and restored with Nanocomposite on buccal surface and Nanoionomer on the palatal surface. The teeth were thermocycled following the restoration. The experimental groups comprised of 72 teeth (3 groups comprising 24 teeth each for fruit drink, fresh fruit juice and soft drink), while remaining 8 formed the control group. Each of experimental group was further divided into three subgroups (low, medium and high immersion). The teeth were finally immersed in Rhodamine B dye, sectioned and evaluated under stereomicroscope. Statistical analyses used were Mann-Whitney test and ANOVA test. RESULTS: The teeth showed statistically significant microleakage as the immersion regime increased. Soft drink group showed highest microleakage followed by fresh fruit juice and fruit drink. Nanocomposite exhibited more microleakage but the comparison was not statistically significant. CONCLUSION: The three beverages used in the study affected the microleakage of both restorative materials significantly. The microleakage scores increased as the frequency of the immersions increased. Soft drink caused highest microleakage followed by fresh fruit juice and fruit drink.

In Vitro Evaluation of Microleakage and Microhardness of Ethanolic Extracts of Propolis in Different Proportions Added to Glass Ionomer Cement.

OBJECTIVE: To evaluate the effect of ethanolic extracts of propolis (EEP) addition in different proportions to glass ionomer cement (GIC) on microleakage and microhardness of GIC. STUDY DESIGN: The cement was divided into four groups: one using the original composition and three with 10%, 25%, and 50% EEP added to the liquid and then manipulated. For microleakage assessment, sixty primary molars were randomly divided into four groups (n=15). Standard Class II cavities were prepared and then filled with EEP in different proportions added to GICs. Microleakage test was performed using a dye penetration method. The data were analyzed using one-way ANOVA and Mann-Whitney U tests (α = 0.05). Disc shaped specimens were prepared from the tested GIC to determine Vickers hardness (VHN). The data were analyzed using one-way ANOVA and post hoc Tukey test (α = 0.05). RESULTS: There were no statistically significant differences between the groups in terms of microleakage (p > 0.05). There were statistically significant differences between the VHN values of groups (p < 0.05). Increasing addition of EEP to GIC statistically significantly increased VHN value of GIC (p < 0.05). CONCLUSIONS: The addition of EEP to GIC increased the microhardness of the GIC and did not adversely affect the microleakage. Thus, it might be used during routine dental practice due to its antibacterial properties.

A Retrospective Study of the 3-Year Survival Rate of Resin-Modified Glass-Ionomer Cement Class II Restorations in Primary Molars.

OBJECTIVE: To determine the three-year survival rate of Class II resin-modified glass-ionomer cement (RMGIC), Vitremer, restorations in primary molars and to compare these results with measurements of survival of Class II restorations of standard restorative materials. STUDY DESIGN: Data on Class II restorations placed in primary molars during a six-year period were collected through a chart review and radiographic evaluation in the office of a board-certified pediatric dentist. A radiograph showing that the restoration was intact was required at least 3 years after placement to qualify as successful. If no radiograph existed, the restoration was excluded. If the restoration was not found to be intact radiographically or was charted as having been replaced before three years it was recorded as a failure. The results of this study were then compared to other standard restorative materials using normalized annual failure rates. RESULTS: Of the 1,231 Class II resinmodified glass-ionomer cement restorations placed over six years 427 met the inclusion criteria. There was a 97.42% survival rate for a 3-year period equivalent to an annual failure rate of 0.86%. CONCLUSIONS: A novel approach comparing materials showed that in this study Vitremer compared very favorably to previously published success rates of other standard restorative materials (amalgam, composite, stainless steel crown, compomer) and other RMGIC studies.

British Society of Prosthodontics Debate on the Implications of the Minamata Convention on Mercury to Dental Amalgam--Should our Patients be Worried?.

In 2013, the Minamata Convention on Mercury called for a global phase-down of amalgam use, with a view to reduce environmental mercury pollution. This will significantly impact UK dentistry, given the still extensive use of amalgam in U.K. general dental practice. However, until now there has been little national discussion or debate. In Spring 2015, The British Society of Prosthodontics dedicated a significant part of its Annual Conference to debating the implications of this issue. Clinical case examples were discussed with audience interaction and voting facilitated using innovative Audience Response System Technology. A remarkable range of concerns and opinions were given. The debate elicited specific concerns amongst clinicians regarding the suitability of mercury-free alternatives to amalgam; particularly where cavities are large and extend beneath the gingival anatomy. There are also anecdotal reports of Dental Foundation (DF) dentists not being adequately taught the use of dental amalgam in undergraduate dental schools. CPD/CLINICAL RELEVANCE: Many clinicians, especially those treating patients for whom moisture control is challenging, feel that amalgam should remain available for clinicians to choose in certain clinical circumstances for the restoration of posterior teeth, even in the event of a complete phase-down.

A root canal filling per se does not have a significant negative effect on the marginal periodontium.

AIM: To evaluate the periodontal status of single-rooted endodontically treated teeth (ET), correcting for patient- and tooth-related factors. METHODS: Clinical parameters (BoP,PD,CAL) of 240 ET and 240 contralateral vital teeth (VT), before and after non-surgical periodontal treatment, were extracted retrospectively from the journals of 175 patients. Possible patient-related (age, gender, smoking status) and tooth-related (interproximal restoration, root canal filling's extent, post, tooth type) confounders were tested. RESULTS: At baseline, frequency of BoP at an interproximal site at ET versus VT was 70.4% versus 65.0%, respectively. The frequency of teeth with interproximal PD ≥ 5 mm and CAL ≥ 5 mm was 47.9% versus 42.9% and 54.6% versus 49.6% at ET and VT, respectively. Interproximal PD and CAL at ET versus VT were 3.86 versus 3.61 mm and 4.11 versus 3.95 mm. After correcting for tooth-related factors, no significant differences were observed between ET and VT. An improper restoration had a significant (p < 0.001) negative effect on BoP [OR 3.49 (95%CI: 1.95-6.27)], PD [36.81% (95%CI: 18.52-57.92)] and CAL [27.01% (95%CI: 12.67-43.18)]. No significant differences between ET and VT were observed regarding clinical outcome of non-surgical periodontal therapy. CONCLUSIONS: Presence of a root canal filling per se does not have a significant negative influence on the marginal periodontium, when correcting for the quality of the interproximal restoration.

Genetic susceptibility to dental caries differs between the sexes: a family-based study.

Many of the factors affecting susceptibility to dental caries are likely influenced by genetics. In fact, genetics accounts for up to 65% of inter-individual variation in dental caries experience. Sex differences in dental caries experience have been widely reported, with females usually exhibiting a higher prevalence and severity of disease across all ages. The cause for this sex bias is currently uncertain, although it may be partly due to the differential effects of genetic factors between the sexes: gene-by-sex interactions. In this family based study (N = 2,663; 740 families; ages 1-93 years), we assessed dental caries via intra-oral examination and generated six indices of caries experience (DMFS, dfs, and indices of both pit-and-fissure surface caries and smooth surface caries in both primary and permanent dentitions). We used likelihood-based methods to model the variance in caries experience conditional on the expected genetic sharing among relatives in our sample. This modeling framework allowed us to test two lines of evidence for gene-by-sex interactions: (1) whether the magnitude of the cumulative effect of genes differs between the sexes, and (2) whether different genes are involved. We observed significant evidence of gene-by-sex interactions for caries experience in both the primary and permanent dentitions. In the primary dentition, the magnitude of the effect of genes was greater in males than females. In the permanent dentition, different genes may play important roles in each of the sexes. Overall, this study provides the first direct evidence that sex differences in dental caries experiences may be explained, in part, by gene-by-sex interactions.

Biomechanical Behavior of Extensively Restored Premolars: Cusp Deformation, Marginal Integrity, and Fracture Resistance.

PURPOSE: To study the biomechanical behavior of extensively restored premolars by determining the effect of the composite type, presence of cusp weakening, and compressive loading on the cusp deformation (CD), marginal integrity (MI), and fracture resistance (FR) of directly restored premolars. MATERIALS AND METHODS: Forty premolars received Class II mesio-occlusal-distal (MOD) cavities and were divided into 4 groups (n = 10) in accordance with the two study variables: composite type (conventional: Filtek Z250 XT [Z250], 3M ESPE; low shrinkage: Venus Diamond [VD], Heraeus-Kulzer) and the presence of cusp weakening (with/without). Cusp deformation upon restoration was assessed using strain gauges during the restorative procedure and thereafter when the restorations were subjected to an occlusal load of 100 N. The samples were subjected to thermal and mechanical cycling. Epoxy resin replicas of the proximal tooth/restoration interfaces were made to analyze the marginal integrity (MI) using scanning electron microscopy. To determine the fracture resistance (FR), the teeth were loaded at a crosshead speed of 0.5 mm/min until fracture. RESULTS: The conventional composite Z250 had higher CD, lower MI, and lower FR than the low-shrinkage composite VD. Cusp weakening had no influence on CD, but MI and FR decreased. CONCLUSION: The low-shrinkage composite VD performed better in restoring extensively destroyed premolars than did Z250.

Ten-year Clinical Performance of Posterior Resin Composite Restorations.

PURPOSE: To investigate the clinical behavior of two different resin-based restorative systems in Class II cavities in a controlled prospective split-mouth study over 10 years. MATERIALS AND METHODS: Thirty patients received 68 resin composite restorations (Solobond M + Grandio: n = 36; Syntac + Tetric Ceram: n = 32) by one dentist in a private practice. 35% of cavities revealed no enamel at the bottom of the proximal box, 48% of cavities provided < 0.5 mm of remaining proximal enamel. Restorations were examined according to modified USPHS criteria at baseline, after 6 months, and 1, 2, 4, 6, 8, and 10 years. RESULTS: Twenty-nine out of 30 patients attended the 10-year recall. The overall success rate of all restorations was 96.9%. One Grandio restoration suffered marginal fracture with exposed dentin and one Tetric Ceram restoration failed due to cusp fracture. After 10 years, Grandio showed higher surface roughness (p = 0.03) and less color match (p = 0.024; Mann-Whitney U-test). Molar restorations performed worse than premolar fillings regarding marginal integrity (4 and 10 years), filling integrity (4, 8, and 10 years), and tooth integrity (4, 8, and 10 years). The main reasons for degradation of resin composites were chipping and cracks in molar restorations after 8 years. Beyond the 4-year recall, marginal staining increased (43% bravo for stained margins at four years, 52% at 8 years, and 71% at 10 years). Tooth integrity deteriorated significantly due to more enamel cracks and chipping over time (9% at baseline and 89% after 10 years (p<0.05). CONCLUSIONS: Direct resin composite restorations performed satisfactorily over 10 years of clinical service.

Evaluation of Microtensile Bond Strength and Microleakage of a Self-adhering Flowable Composite.

PURPOSE: To evaluate the microtensile bond strength (µTBS) and marginal sealing ability of a self-adhering flowable composite between dentin and composite interfaces, as well as the microleakage of Class V restorations. MATERIALS AND METHODS: The occlusal thirds of 40 third molars were removed and randomly divided into 4 groups according to the applied adhesive: Adper Easy One (AEO, 3M ESPE), Clearfil SE Bond (CSEB, Kuraray), Prime & Bond NT (PBNT, Dentsply) and a self-adhering flowable composite (Dyad Flow, DF, Kerr). Filtek Flowable (3M ESPE) resin composite crowns were then built up in the first three groups; in group DF, composite crowns were built up without the application of an adhesive. Thirty stick-shaped microspecimens were prepared per group, 10 of which were used for morphological observation of bonded interfaces by scanning electron microscopy (SEM) after decalcification. The remaining microspecimens underwent microtensile bond strength testing and the failure mode was analyzed. Microleakage evaluation was performed on 10 premolars per group in which standardized box-shaped Class V cavities were prepared. After 500 thermocycles, the premolars were immersed in 1% methylene blue for 24 h, and three slices from each tooth were observed under a stereomicroscope and scored. Statistical analysis was performed using one-way ANOVA, Student-Newman-Keuls and chi-square tests. RESULTS: The PBNT group presented the highest µTBS values, followed by the CSEB and AEO groups, which did not differ significantly from each other. The DF group showed the lowest µTBS values. No significant differences in microleakage were observed among these four groups. CONCLUSION: Although individual usage of the self-adhering flowable composite showed the lowest bond strength, the same marginal sealing ability was observed as that of combining self-etching and etch-and-rinse adhesives with flowable composite.

Marginal Quality of Class II Composite Restorations Placed in Bulk Compared to an Incremental Technique: Evaluation with SEM and Stereomicroscope.

PURPOSE: To evaluate the marginal quality of composite resin restorations placed in extracted molars either in bulk (4 mm) or three increments. MATERIALS AND METHODS: Sixteen extracted mandibular molars were selected and two two-surface cavities were prepared in each tooth (proximal depth 4 mm, occlusal width 5 mm). On one side of the tooth, Tetric EvoCeram Bulk Fill (Ivoclar Vivadent) was applied in a single increment; on the other side, Tetric EvoCeram (Ivoclar Vivadent) was applied in three increments: a horizontal gingival, an oblique buccal, and an oblique lingual increment. Each layer was light cured for 10 s with a Bluephase G2 curing light (1200 mW/cm2). Two adhesive systems were employed according to the instructions for use: the single-component etch-and-rinse system ExciTE F (Ivoclar Vivadent) and the self-etching two-component system AdheSE (Ivoclar Vivadent). The adhesive was light cured for 10 s with a Bluephase G2 curing light (1200 mW/cm2). Eight fillings were placed for each test group and all restoration margins were confined to the enamel. After 10,000 cycles of thermocycling (5°C/55°C), the quality of the proximal margins was semiquantitatively directly evaluated with a stereomicroscope at low magnification and a dental explorer using the SQUACE (semi-quantitative evaluation of restorations) method. In addition, replicas were made for SEM analysis, which was carried out four weeks later at high magnification (200X) by measuring the percentage of regular proximal margins in relation to the entire margin. RESULTS: After thermocycling, statistically significantly higher percentages of regular margins were detected for those fillings placed with the etch-and-rinse system ExciTE F than for those placed with the self-etching system AdheSE - irrespective of the evaluation method (Mann-Whitney non-parametric test, p < 0.05). There was no statistically significant difference between the resin restorations placed in bulk and those placed in three increments (Mann-Whitney, p > 0.05). The semi-quantitative evaluation by means of a light microscope yielded statistically significantly higher values for regular margin than did the SEM evaluation for all 4 test groups (p < 0.05). Pearson's correlation coefficient for both evaluation groups was 0.87 (p < 0.0001). CONCLUSIONS: The marginal quality of medium-sized Class II restorations of composite resins placed in one increment was similar to that of restorations placed in several increments. The semiquantitative evaluation of the marginal quality with an explorer at low magnification is an effective and rapid method to predict the clinical performance of direct restorations.

Randomized 3-year clinical evaluation of Class I and II posterior resin restorations placed with a bulk-fill resin composite and a one-step self-etching adhesive.

PURPOSE: To evaluate the 3-year clinical durability of the flowable bulk-fill resin composite SDR in Class I and Class II restorations. MATERIALS AND METHODS: Thirty-eight pairs of Class I and 62 pairs of Class II restorations were placed in 44 male and 42 female patients (mean age 52.4 years). Each patient received at least two extended Class I or Class II restorations that were as similar as possible. In all cavities, a one-step self-etching adhesive (XenoV+) was applied. One of the cavities of each pair was randomly assigned to receive the flowable bulk-fill resin composite SDR in increments up to 4 mm as needed to fill the cavity 2 mm short of the occlusal cavosurface. The occlusal part was completed with an ormocer-based nanohybrid resin composite (Ceram X mono+). In the other cavity, only the resin composite CeramX mono+ was placed in 2 mm increments. The restorations were evaluated using slightly modified USPHS criteria at baseline and then annually for 3 years. Caries risk and bruxing habits of the participants were estimated. RESULTS: No post-operative sensitivity was reported. At the 3-year follow-up, 196 restorations - 74 Class I and 122 Class II - were evaluated. Seven restorations failed (3.6%), 4 SDR-CeramX mono+ and 3 CeramX mono+ only restorations, all of which were Class II. The main reason for failure was tooth fracture, followed by resin composite fracture. The annual failure rate (AFR) for all restorations (Class I and II) was 1.2% for the bulkfilled restorations and 1.0% for the resin composite-only restorations (p > 0.05). For the Class II restorations, the AFR was 2.2% and 1.6%, respectively. CONCLUSION: The 4-mm bulk-fill technique showed good clinical effectiveness during the 3-year follow-up.

Class I restoration margin quality in direct resin composites: A double-blind randomized controlled clinical trial.

PURPOSE: To evaluate the margin quality of direct resin composite restorations comparing the enamel-dentin adhesive standard procedure with additional use of adhesive layer at the external outline. METHODS: A total of 648 teeth with Class I occlusal lesions in molars and premolars were randomly selected and distributed into two groups of 324 each in order to compare the margin quality with two restoration strategies. Lesions were sealed with the standard adhesion procedure for direct resin composite restorations (Group 1) and with an additional procedure of enamel adhesive on the outer boundary of the finished restoration (Group 2). Evaluation of marginal quality at 6, 12, 24, 36 and 48 months was performed and described as good marginal adaption or as poor quality defined as Inadequacy A (IA): overhanging resin or change of color; Inadequacy B (IB): the presence of a gap at the enamel-composite interface that retained the probe tip; or Inadequacy C (IC) presence of gap at the enamel-composite interface with explorer tip penetration of more than 1 mm. RESULTS: Data showed a higher number of Inadequacy A for restorations with the additional technique for marginal seal (Group 2): 16 of 24 total (57%) at 6 months; 28 of 37 total (76%) at 12 months; 36 of 44 total (82%) at 18 months; 22 of 33 total (67%) at 24 months; 14 of 21 total (70%) at 36 months and 16 of 25 total (64%) at 48 months. The Inadequacy B and C of marginal seal were more prevalent for restorations without the additional marginal seal (Group 1): 18 of 28 total (64%) at 12 months with inadequacy B; 19 of 25 total (76%) with inadequacy B and 16 total (100%) with inadequacy C at 18 months; 9 of 17 total (53%) with Inadequacy B and 13 total (100%) with Inadequacy C at 24 months; 12 of 17 total (70%) with Inadequacy B and 9 of 13 total (73%) with Inadequacy C at 36 months; 14 of 24 total (58%) with Inadequacy B and 7 of 11 total (63%) with Inadequacy C at 48 months.

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

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

A study of primary teeth restored by intracoronal restorations in children participating in an undergraduate teaching programme at Cork University Dental School and Hospital, Ireland.

AIM: To study the outcomes for restored primary molar teeth; to examine outcomes in relation to tooth type involved, intracoronal restoration complexity and to the material used. DESIGN: Retrospective study of primary molar teeth restored by intracoronal restorations. A series of restored primary molar teeth for children aged 6-12 years was studied. The principal outcome measure was failure of initial restoration (re-restoration or extraction). Three hundred patient records were studied to include three equal groups of primary molar teeth restored with amalgam, composite or glass ionomer, respectively. Restorative materials, the restoration type, simple (single surface) or complex (multi-surface) restoration, and tooth notation were recorded. Subsequent interventions were examined. Data were coded and entered into a Microsoft Excel database and analysis undertaken using SPSS v.18. Statistical differences were tested using the Chi square test of statistical significance. RESULTS: Of the 300 teeth studied, 61 restoration failures were recorded with 11 of those extracted. No significant differences were found between outcomes for upper first, upper second, lower first or lower second primary molars. Outcomes for simple primary teeth restored by intracoronal restorations were significantly better than those for complex intracoronal restorations (P = 0.042). Teeth originally restored with amalgam accounted for 19.7% of the 61 failures, composite for 29.5%, while teeth restored with glass ionomer represented 50.8% of all restoration failures. The differences were significant (P = 0.012). CONCLUSIONS: The majority (79.7%) of the 300 restored primary teeth studied were successful, and 3.7% teeth were extracted. Restorations involving more than one surface had almost twice the failure rate of single surface restorations. The difference was significant. Significant differences in failure rates for the three dental materials studied were recorded. Amalgam had the lowest failure rate while the failure rate with glass ionomer was the highest.