BACKGROUND: An optimum restoration for reconstructing endodontically treated teeth should provide excellent marginal adaptation, high fracture resistance as well as maximum tooth structure conservation. The purpose of this study was to evaluate the marginal adaptation and fatigue resistance of different coronal restorations in endodontically treated premolars.
METHODS: Thirty sound maxillary first premolars were endodontically treated and received MOD cavities. Teeth were randomly allocated into three groups (n = 10) according to the type of coronal restoration: Group R: polyethylene fibers (ribbond), fibers-reinforced composite (everX posterior) and final layer of nano-hybrid composite. Group O: indirect lithium disilicate overlay and Group C: fiber-post, resin composite restoration, and lithium disilicate crown. Marginal gap assessment was performed before and after thermocycling (5000 cycles) using stereomicroscope. Samples were subjected to stepwise-stress loading starting at 200 N, and increased by 100 N in each step until failure occurred. Statistical analysis was done by One-way ANOVA followed Tukey`s Post Hoc test for multiple comparison. Paired t test was used to compare the marginal adaptation before and after thermocycling. Survival probability was evaluated by Life table survival analysis. Failure mode analysis was performed with Chi-square test.
RESULTS: Marginal gap was significantly the lowest in group R (37.49 ± 5.05) and (42.68 ± 2.38), while being the highest in group C (59.78 ± 5.67) and (71.52 ± 5.18) in before and after thermocycling respectively (P < 0.0001). Fatigue resistance was the highest for group O (1310.8 ± 196.7), and the lowest for group R (905.4 ± 170.51) with a significant difference between groups (P < 0.0001). Crown group had the highest percentage (80%) of catastrophic failure, while, overlay group exhibited the lowest (20%).
CONCLUSIONS: Direct restoration without cuspal coverage using ribbon fibers with short FRC provided better marginal adaptation than indirect overlays and crowns, but fatigue resistance wasn\'t significantly improved. Adhesive ceramic overlays showed the best fatigue performance and the least catastrophic failure rate compared to both direct fiber-reinforced composite and indirect ceramic full coverage restorations.
CONCLUSIONS: Indirect adhesive overlays are a suitable, more conservative restorative option for endodontically treated teeth than full coverage restorations, especially when tooth structure is severely compromised.

OBJECTIVE: This study evaluated the effect of cervical margin relocation (CMR) with two different materials and contamination with hemostatic agents on the margin adaptation and microleakage of ceramic restorations.
METHODS: Mesial-occlusal-distal cavities were prepared in 60 human first molars and distributed to 3 groups (n = 20) according to the margin relocation procedure. The groups were: group F; flowable composite applied in two 2 mm increments, group B; bulk-fill flowable composite applied as a bulk increment of 4 mm thickness and group C (control); no CMR was done. Each group was subdivided into two subgroups (subgroup N; no hemostatic agent applied and subgroup H; hemostatic agent was applied). In all groups, ceramic inlays were prepared and cemented. The samples were subjected to thermocycling (10,000 cycles). The adaptation of the cervical margin was evaluated with scanning electron microscopy (200×). Samples were then assessed for microleakage analysis with the dye penetration method. Marginal adaptation data were normally distributed and analyzed using two-way ANOVA followed by Tukey\'s post hoc test. Ordinal microleakage score data were analyzed using cumulative link models followed by the analysis of deviance using Wald chi-square tests.
RESULTS: Both CMR and contamination with a hemostatic agent had significant effects on the margin adaptation of the cervical margin. Group C showed the highest adaptation with no significant difference from group F. The lowest adaptation was revealed in group B with a significant difference from group C. Subgroup N (in all groups) showed a statistically higher adaptation than subgroup H. Regarding microleakage assessment, CMR had no significant effect but hemostatic agent application showed a significantly higher microleakage score for all groups.
CONCLUSIONS: Both the CMR procedure and contamination with AlCl3 hemostatic agent had a negative effect on marginal adaptation. For microleakage assessment, only contamination with hemostatic agent negatively affected the microleakage with no effect on the margin relocation procedure.

OBJECTIVE: The interrelationships between dental prostheses, abutments, and supporting periodontal tissue are dynamic. Clinical studies assessing the quality and associated complications of fixed dental prostheses (FDPs) in the Saudi population are scarce. The aims of this project were to assess the location and accuracy of marginal adaptation and proximal contact quality of FDPs provided by dentists in the Kingdom of Saudi Arabia and to assess the impact of these factors on the health of the periodontium and caries susceptibility.
METHODS: This retrospective cohort study collected demographic, dental, and social history data from patients with FDPs. Fixed dental prostheses quality was assessed using the United States Public Health Service Criteria, and periodontal health indices were measured. Descriptive and inferential statistics were used for data analysis. Logistic and multiple linear regression analyses were performed to assess predictors of caries risk and periodontal disease, respectively.
RESULTS: Sixty-two patients with 62 FDPs were assessed. The mean patient age was 32.45 ± 9.0 (19-61) years with a male-to-female ratio of 3:1. On the assessment, 74.2% had marginal discrepancy, 54.8% had subgingival margins, 22.6% had open or tight proximal contacts, and 8.1% had marginal caries. Well-adapted margins promoted periodontal health, and inadequate proximal contact increased the risk of marginal caries.
CONCLUSIONS: This study suggests that 26% of FDPs provided by dental practitioners in the Western province, Kingdom of Saudi Arabia, were of high marginal fit and proximal contact quality.
CONCLUSIONS: Constructing FDPs with high-quality marginal fit and proximal contact promotes periodontal health and reduces caries risk, thereby improving FDP outcome.

The current restorative materials used for cervical lesions restoration still need to be improved. A low E-modulus restorative material Bondfill SB (group BF) is developed. This study was to evaluate marginal adaptation and nanoleakage expression at dentin bonding interface of BF before and after artificial aging cycling when used for class V cavity restoration in vitro. Cavities were prepared in human premolars and restored with either Bondfill SB or Z100 (group SZ). Quantitative data were analyzed by t-test (α = 0.05). Before cycling, there was no significant differences between groups for perfect margin and modes of failure. After cycling, SZ showed a higher (p = 0.002) perfect margin value (55.08 ± 15.20%) and less (p = 0.01) adhesive failure (35.35 ± 15.02%) to enamel than BF (25.15 ± 12.47% and 61.78 ± 15.41%, respectively). BF exhibited less (p = 0.01) adhesive failure (12.89 ± 5.58%) to dentin than SZ (44.17 ± 17.50%). BF showed more cohesive failures at both enamel (12.01 ± 3.65%) (p < 0.0001) and dentin (9.58 ± 3.14%) (p = 0.02) sides than SZ (0.77 ± 1.21% and 4.68 ± 1.39%, respectively). Transmission electron microscope (TEM) showed that hybrid layers in SZ and BF were around 0.5 μm thick. Before cycling, more silver deposits were found at dentin bonding interface in SZ. After cycling, the deterioration in SZ mostly occurred at the bottom and on the surface of the hybrid layer. While in BF, the deterioration occurred at the bottom of the hybrid layer and in Bondfill SB. BF showed a more reliable dentin bonding after artificial aging and might buffer the cervical stress concentration. Bondfill SB may be a new promising choice for long-term success of cervical lesions restoration. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2050-2056, 2019.

OBJECTIVE: This survey was undertaken to assess dentist\'s opinion regarding the occurrence and pattern of food impaction in relation to fixed partial denture (FPD) prostheses, its commonly observed consequences, factors contributing to it, and its management.
METHODS: A descriptive survey was conducted on a sample size of 150 dental practitioners. The pro forma consisted of informed consent, demographic information, and questionnaire. The results were tallied and quantitative analysis was performed to obtain the descriptive statistics for the data using SPSS version 20.
CONCLUSIONS: All the study respondents had come across patients who complained of food impaction in relation to FPD. The most common consequences of food impaction were proximal caries of the adjacent teeth and interdental bone loss. Majority of the dentists considered faulty FPD design with improper contact relation, improper crown contour, poor margin adaptation, and faulty pontic design as the most likely reason for food impaction. Repeating the FPD with emphasis on prescribing and reinforcing the use of proper interdental aids was considered as the ideal treatment option. It was also observed that about half of the dentists always communicated inadequate information of the FPD prostheses that needed replacement to the dental laboratory technician for the successive bridge. Most of the times, prosthodontists were consulted to rectify the problem of food impaction resulting from faulty FPD prostheses. However, it is obvious that it is easier and more prudent to prevent rather than treat food impaction. This study gives an overview of some of the common errors in designing the FPD prostheses which often lead to food impaction and measures to be taken to overcome them.
CONCLUSIONS: It may be concluded as all the dentists participating in the survey agreed that food impaction is one of the common complaint among FPD Patients. Proximal caries and interdental bone loss were the prevalent outcomes of food impaction. Faulty FPD design was allegedly attributed as the reason for food impaction. Prosthodontists were routinely consulted to resolve the dilemma of food impaction. However, it is rational to prevent food impaction rather than to tackle the sequel later.

Finger prosthesis often needs refabrication due to its discoloration following use. This article presents a novel, economical, and cost-effective technique to duplicate the patient׳s existing prosthesis to obtain a new wax replica, which is then clinically tried and processed to obtain new silicone finger prosthesis. This technique requires comparatively less clinical and laboratory steps as to fabricate an entirely new prosthesis. The newly fabricated silicone finger prosthesis has the fit and marginal adaptation of the patient׳s existing prosthesis but the esthetics is improved.

OBJECTIVE: To evaluate the cervical marginal and internal adaptation of posterior bulk fill resin composites of different viscosities, before and after thermo-cycling (TMC).
METHODS: Eighty box-only class II cavities were prepared in 40 extracted human premolars with the distal proximal box beneath the enamel-cementum junction (CEJ). The teeth in the experimental groups were restored with bulk fill resin composite restorations (Gr. I- Sonic Fill, Gr. II- SDR, Gr. III- Tetric N Ceram Bulk Fill or a conventional composite designed for 2-mm increments (Gr. IV- Tetric N Flow along with Tetric N Ceram). Before and after thermal cycling, the gap-free marginal length was analyzed using SEM of epoxy resin replicas. After thermal cycling, specimens were cut longitudinally in order to investigate internal dentine adaptation by epoxy replicas under SEM (500 × magnification).
RESULTS: Statistical analysis was performed using the ANOVA and Tukey Post Hoc tests (P < 0.05). In enamel, high percentages of gap-free margins were initially identified for all the groups, which declined after thermal cycling. However, no significant differences were identified among any of the groups (P > 0.05). In dentine, bulk fill groups performed at par with the incremental placement; for both marginal and internal adaptation (P < 0.05), for all materials except Tetric N Ceram Bulk Fill.
CONCLUSIONS: Viscosity of the bulk fill restorative material influenced the proportion of gap-free marginal interface and the internal adaptation in dentin.

OBJECTIVE: To examine the effects of composite type (bulk-fill/conventional) and placement (4-mm bulk/2-mm increments) on internal marginal adaptation of Class I preparations.
METHODS: Cylindrical, Class I, 4-mm×4-mm preparations were made on 50 recently extracted human molars and restored using either a bulk-fill (SureFil SDR Flow (SDR), Quixx (QX), SonicFill (SF), Tetric EvoCeram Bulk (TEC)) or a conventional composite designed for 2-mm increments (Filtek Supreme Ultra (FSU)). Restorations were placed in 1 or 2 increments using the manufacturer\'s bonding agent and curing light (n=5). Teeth were sectioned occluso-gingivally and dye was placed on the internal margin and visually examined by 3 observers. Gap-free marginal lengths were analysed within three different regions of the sectioned tooth: enamel, mid-dentine, and pulpal floor.
RESULTS: Marginal integrity was unaffected by placement method. Bulk-placement demonstrated significantly fewer gap-free margins at the pulpal floor than in enamel, for all materials except SDR. Greater percentages of gap-free margins were found within the mid-dentine than at the pulpal floor for FSU. QX had more gap-free margins in enamel compared with the mid-dentine. Proportion of gap-free margins within enamel and mid-dentine was not significantly different for any incrementally placed product. Excluding FSU, gap-free margins within enamel were significantly greater than at the pulpal floor. Notably, significantly more gap-free margins were found within mid-dentine than at the pulpal floor for SF.
CONCLUSIONS: No significant differences in gap-free margins were found between placement methods within a given product per location. Except for SDR, percentage of gap-free margins was significantly lower at the pulpal floor interface than at the enamel interface for bulk-fill.