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ABSTRACT Objectives Material and Methods Results Conclusions Clinical Significance To analyze survival and complication rates for anterior and premolar laminate‐veneers out of different ceramic materials (feldspathic, leucite‐reinforced glass–ceramic [LRGC], lithium‐disilicate [LDS] and zirconia).A systematic literature search was conducted across multiple databases for clinical studies on ceramic laminate‐veneers with a minimum‐follow‐up of ≥ 1 year. The date of last search was on February 19, 2024. Survival, technical, esthetic and biological events were assessed for different laminate‐veneer materials at three observation periods (short‐ [1–3 years], mid‐ [4–6 years] and long‐term [≥ 7 years]).Twenty‐nine studies were included. Meta‐analysis revealed a pooled survival‐rate of 96.13% for feldspathic, 93.70% for LRGC and 96.81% for LDS at 10.4 years. No difference was found between materials. Complication rates (technical/esthetic/biological) were as follows: Feldspathic: 41.48%/19.64%/6.51%; LRGC: 29.87%/17.89%/4.4%; LDS: 6.1%/1.9%/0.45% at 10.4 years. Zirconia showed a 100% survival‐rate with no complications at 2.6 years. No long‐term data was available for zirconia.Feldspathic, LRGC and LDS laminate‐veneers showed high survival‐rates at long‐term observation. LDS slightly outperforms feldspathic and LRGC laminate‐veneers with lower long‐term complication rates. More studies providing long‐term data on zirconia laminate‐veneers are needed.Ceramic laminate‐veneers are a reliable treatment option. LDS may be preferred as a restorative material for long‐term success. [ABSTRACT FROM AUTHOR]

The primary aim of this in vitro study was to compare the load-bearing capacity of lithium disilicate occlusal veneers, fabricated via different manufacturing processes. Secondary objectives included assessing internal accuracy and production time-efficiency. Four fabrication methods for ultra-thin lithium disilicate occlusal veneers on extracted human molars with simulated erosive defects were compared (n = 20/group): CAM: milled lithium disilicate (IPS e.max CAD); HPR: heat-pressed lithium disilicate (IPS e.max Press) out of a milled PMMA template (Ddpmma CAST); 3DP: 3D-printed lithium disilicate (experimental lithium disilicate); PTE: heat-pressed lithium disilicate (IPS e.max Press) out of a 3D-printed template (SilaPrint cast). Internal accuracy was measured prior to thermo-mechanical aging, followed by static loading to measure the load-bearing capacity (F max). Fabrication time (time-efficiency) was also recorded. Statistical analysis was performed using the Kruskal-Wallis (KW) test. No statistically significant differences were found in median load-bearing capacities (F max) between the groups (KW p = 0.5902): CAM 1821 N, HPR 1896 N, 3DP 2003 N, PTE 1687 N. Significant differences were found in internal accuracy between the groups that employed printing processes (3DP, PTE) and all other groups in margins (p < 0.001), cusps (p < 0.0018), and fossae (p < 0.0346). The time-efficiency measurements indicated an increase in fabrication time, starting from CAM 67.2 ± 5.8 min, followed by HPR 200.8 ± 33.0 min, PTE 289.2 ± 38.7 min, and peaking with the highest duration observed for 3DP 701.6 ± 8.1 min. The fabrication method of ultra-thin lithium disilicate occlusal veneers does not significantly impact their load-bearing capacity, but affects the clinical fit and adaptation of the veneers. • All fabrication methods exhibited high load-bearing capacities, with no significant differences between the groups. • Milled or heat-pressed restorations demonstrated minimal marginal discrepancies and high internal accuracy. • 3D-printed restorations showed larger marginal gaps but superior internal accuracy in the cusp and fossa regions. • Direct milling was the most time-efficient; 3D-printing the most time-consuming, and procedures involving methacrylate-based templates were intermediate. [ABSTRACT FROM AUTHOR]

Background. Multilayer zirconia has more optical and aesthetic features than regular zirconia. Therefore, its mechanical properties should be compared with monochromatic zirconia. Among the mechanical characteristics that can be checked are the wear of the opposite tooth and the bond to the porcelain. This study assessed the effect of zirconia type (multilayer versus monochromatic) on the shear bond strength (SBS) to feldspathic porcelain and the wear of the opposing teeth. Methods. The present in vitro study was conducted in two phases. In the first phase, 15 multilayer and 15 monochromatic zirconia blocks measuring 10×5×5 mm were designed, milled, sintered, veneered with porcelain, and underwent thermocycling. Their SBS was then measured in a universal testing machine. In the second phase, 15 multilayer and 15 monochromatic zirconia blocks were placed in a chewing simulator, and 30 sound premolars served as antagonistic teeth. The magnitude of wear of the buccal cusp of premolars was quantified from a 4-mm reference point after 100000 cycles. Data were analyzed by independent t test (α=0.05). Results. The mean SBS of monochromatic zirconia to porcelain (24.49±3.58 MP) was slightly higher than that of multilayer zirconia (22.98±2.98 MP), but the difference was not significant (P>0.05). The mean wear of the opposing teeth was also slightly higher in the monochromatic group (284.1±66.53 µm) than in the multilayer group (263.2±58.69 µm), but this difference was not significant either (P>0.05). Conclusion. Monochromatic and multilayer zirconia showed comparable SBS to feldspathic porcelain and caused comparable wear of the opposing teeth in vitro. Thus, multilayer zirconia may serve as an alternative to monochromatic zirconia.

Porcelain laminate veneers (PLV) offer a conservative aesthetic solution for interdental space closure. However, space is typically not distributed symmetrically, and the mesiodistal width of the restored teeth may increase unless multiple teeth are prepared for conventional PLV to maintain appropriate individual tooth proportion. Ceramic fragments can be suggested to close the space without modifying tooth size and dental proportion. This article presents two cases where interdental gaps were closed using lingually placed porcelain laminate (LPPL). All stages of the restorative procedures, including treatment planning, temporization, tooth preparation, and cementation of these delicate restorations, are detailed. Based on the results of these clinical reports, we regard the use of LPPL as a successful treatment option in selected cases, as evidenced by 2- and 6-year follow-ups. The Modified United State Public Health Criteria is reported. [ABSTRACT FROM AUTHOR]

In addition to many materials, silver vanadate (AgVO3) has gained interest due to its antimicrobial properties, which opens up the potential for use as an antibacterial agent for biomedical applications. This work aimed to study the effect of AgVO3 addition on the structural and morphological properties of a developed dental porcelain (DP) prepared from natural raw materials. AgVO3 nanowires, prepared by the coprecipitation method, were added in different amounts (1, 3, and 5 wt.%) to a DP mass with the initial composition of 80 wt.% feldspar, 15 wt.% quartz, and 5 wt.% kaolin, obtained by sintering the mixture at 1300 °C. The structural and morphological properties of AgVO3 and DP were investigated by X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), and transmission electron microscopy (TEM). The results showed the formation of α-AgVO3 nanowires coated with semispherical metallic silver nanoparticles. Moreover, α-AgVO3 additions do not influence the structural and morphological properties of DP, with the presence of Ag and V clearly identified in the DP with the α-AgVO3 addition. Our findings highlight the potential of this novel material for use in various dental applications. Future studies need to establish the antibacterial properties of the prepared dental material. [ABSTRACT FROM AUTHOR]

PURPOSE. This study assessed the effect of storage time on chemical structure of a single-bottle and a two-bottle experimental ceramic primer and micro-shear bond strength (µSBS) of composite to ceramic. MATERIALS AND METHODS. This study was conducted on 60 sintered zirconia and 60 feldspathic porcelain blocks. Half of the specimens (n = 30) were subjected to surface treatment with the single-bottle Clearfil ceramic primer (n = 15) and two-bottle experimental primer (n = 15) after 24 hours. The remaining half received the same surface treatments after 6 months storage in distilled water. Composite cylinders were bonded to the ceramics, and they were then subjected to µSBS test. Also, the primers underwent Fourier-transform infrared spectroscopy (FTIR) after 24 hours and 6 months to assess their chemical structure. Data were analyzed with 3-way ANOVA and adjusted Bonferroni test (alpha = 0.05). RESULTS. The µSBS of both ceramics significantly decreased at 6 months in one-bottle ceramic primer group (P = .001), but it was not significantly different from the two-bottle experimental primer group (P = .635). FTIR showed hydrolysis of single-bottle primer, cleavage of silane and 10-MDP bonds, and formation of siloxane bonds after 6 months. CONCLUSION. Six months of storage caused significant degradation of single-bottle ceramic primer, and consequently had an adverse effect on µSBS. [ABSTRACT FROM AUTHOR]

IntroductionThe aim of this study was to evaluate the fit performance of implant infrastructures manufactured by five different techniques: heat-press (IPS), milling (ZIR), lost wax (CER), calcinable cylinder (CAL), and CAD/Waxx® (CAD).MethodsThe methodology was based on the Replica Technique, which can simulate and evaluate the fit of the infrastructure on the implant component. Thus, each infrastructure was internally filled with low-viscosity silicone addition and seated on the component until its final setting, obtaining the replica of the cementation space. After removing the coping containing the silicone film, light-density silicone was inserted addition in place of the components, and in its surroundings, condensation silicone was applied, establishing support for the assembly. The joint was sectioned mesiodistally, photographed, and analyzed in image processing software in order to measure the thickness of the interface infrastructure/implant at five different areas: marginal opening (M), gingival-axial angle (G-A), axial region (A), axial-occlusal angle (A-O) and occlusal surface (O).ResultsThe lowest and the highest average thickness between groups was, respectively, IPS: 187.5 μm and CAD: 221.6 μm, with statistically significant differences (p

Despite the development of implant-supported prostheses, there are still patients for whom conservative treatments such as resin-bonded fixed dental prostheses (RBFDPs) are more appropriate. This study's objective was to analyze the available research on full-ceramic RBFDPs. In this study, Web of Science, MEDLINE/PubMed, Scopus, Embase, Cochrane Library, and Google Scholar databases were searched for articles published in English between 2010 and 2020. A total of 14 studies were reviewed based on the eligibility criteria. The results showed that using a cantilever design with one abutment had an advantage over two abutments. Additionally, it was proposed that preparations designed with retentive aids, such as a proximal box, groove, and pinhole, could improve RBFDP survival rates. IPS e.max ZirCAD, In-Ceram alumina, and zirconia CAD/CAM were the most commonly used framework materials. Most studies used air abrasion, salinization, or hydrofluoric acid for surface treatment. Adhesive resin cements were the most frequently used type of cement. The survival rate of In-Ceram ceramics (85.3%–94.8%) was lower than that of In-Ceram zirconia and IPS e.max ZirCAD. Debonding, followed by framework fracture, was the leading cause of failure. Following 3–10 years follow-up, the survival percentage of all-ceramic RBFDPs ranged from 76% to 100%. Although RBFDPs have demonstrated satisfactory success as a conservative treatment, long-term follow-ups and higher sample sizes in clinical research are required to gain more reliable outcomes on the clinical success rate of various RBFDP designs. [ABSTRACT FROM AUTHOR]

Background.: Multilayer zirconia has more optical and aesthetic features than regular zirconia. Therefore, its mechanical properties should be compared with monochromatic zirconia. Among the mechanical characteristics that can be checked are the wear of the opposite tooth and the bond to the porcelain. This study assessed the effect of zirconia type (multilayer versus monochromatic) on the shear bond strength (SBS) to feldspathic porcelain and the wear of the opposing teeth. Methods.: The present in vitro study was conducted in two phases. In the first phase, 15 multilayer and 15 monochromatic zirconia blocks measuring 10×5×5 mm were designed, milled, sintered, veneered with porcelain, and underwent thermocycling. Their SBS was then measured in a universal testing machine. In the second phase, 15 multilayer and 15 monochromatic zirconia blocks were placed in a chewing simulator, and 30 sound premolars served as antagonistic teeth. The magnitude of wear of the buccal cusp of premolars was quantified from a 4-mm reference point after 100000 cycles. Data were analyzed by independent t test (α=0.05). Results.: The mean SBS of monochromatic zirconia to porcelain (24.49±3.58 MP) was slightly higher than that of multilayer zirconia (22.98±2.98 MP), but the difference was not significant (P >0.05). The mean wear of the opposing teeth was also slightly higher in the monochromatic group (284.1±66.53 µm) than in the multilayer group (263.2±58.69 µm), but this difference was not significant either (P >0.05). Conclusion.: Monochromatic and multilayer zirconia showed comparable SBS to feldspathic porcelain and caused comparable wear of the opposing teeth in vitro. Thus, multilayer zirconia may serve as an alternative to monochromatic zirconia. [ABSTRACT FROM AUTHOR]

Porcelain laminate veneers (PLV) offer a conservative aesthetic solution for interdental space closure. However, space is typically not distributed symmetrically, and the mesiodistal width of the restored teeth may increase unless multiple teeth are prepared for conventional PLV to maintain appropriate individual tooth proportion. Ceramic fragments can be suggested to close the space without modifying tooth size and dental proportion. This article presents two cases where interdental gaps were closed using lingually placed porcelain laminate (LPPL). All stages of the restorative procedures, including treatment planning, temporization, tooth preparation, and cementation of these delicate restorations, are detailed. Based on the results of these clinical reports, we regard the use of LPPL as a successful treatment option in selected cases, as evidenced by 2- and 6-year follow-ups. The Modified United State Public Health Criteria is reported.

Abstract Trial design This is a randomized, controlled, superiority, double-blinded, parallel-group, two-arms trial with an allocation ratio of 1:1. The aim of this trial was to compare the two-year clinical performance of partial indirect restorations fabricated from CAD/CAM nano-hybrid composite and ceramic lithium disilicate blocks using the modified USPHS criteria. Methods In two parallel groups (n = 50 restorations), fifty participants having mutilated vital teeth with a minimum of two remaining walls were randomly enrolled in this trial and received indirect restorations of either nano-hybrid composite resin blocks (Brilliant, Coltene, Switzerland) or Lithium Disilicate (IPS Emax CAD). The restorations were assessed using modified USPHS criteria by two independent blinded assessors at baseline, six months, one-year and two years follow-up visits. Categorical and ordinal data were presented as frequencies and percentages. Categorical data were analyzed using the chi-square test. Ordinal data were analyzed using the Mann-Whitney U test for intergroup comparisons and Freidman’s test followed by the Nemenyi post hoc test for intragroup comparisons. Numerical data were presented as mean and standard deviation values. They were analyzed for normality using the Shapiro-Wilk test. Data were found to be normally distributed and were analyzed using the independent t-test. The significance level was set at p ≤ 0.05 within all tests. Results Forty-eight participants received the allocated intervention and completed the follow-up periods. There was a statistically significant difference between both tested materials for all USPHS criteria regarding Marginal integrity and Marginal discoloration at six-months Follow-up, but with no statistically significant difference at one- and two-year follow-up. Conclusions Both materials showed an acceptable, successful clinical performance along the two-years follow-up period. Clinical relevance The CAD/CAM nano-hybrid composite blocks are as reliable as Lithium disilicate for restoring mutilated vital teeth.

Objectives: The objective of this in vitro study was to evaluate the shear bond strength between the ceramic veneer and additively manufactured titanium with different surface treatments, and to compare with milled titanium. Also, to characterize the surface and the presence of an α‐case layer of additively manufactured and milled titanium. Material and Methods: Sixty additively manufactured titanium grade 23, and 20 milled titanium grade 4 cylindrical specimens were divided into four groups based on surface treatments, air‐particle abrasion and grinding. After ceramic veneering half of each group were thermocycled. The bond strength was analyzed using a shear bond strength test. The surfaces were analyzed using interferometry and scanning electron microscopy. Results: The grinding procedure and air‐particle abrading pressure had no significant effect on the shear bond strength (p =.264 and p =.344). Thermocycling showed a tendency towards an effect but not significant (p =.052). The group with the highest air‐abrading pressure showed the highest surface roughness. No presence of an α‐case layer was detected in any of the groups. Conclusion: Additively manufactured titanium grade 23 may be veneered with ceramics without prior grinding of the surfaces. [ABSTRACT FROM AUTHOR]

In addition to many materials, silver vanadate (AgVO3) has gained interest due to its antimicrobial properties, which opens up the potential for use as an antibacterial agent for biomedical applications. This work aimed to study the effect of AgVO3 addition on the structural and morphological properties of a developed dental porcelain (DP) prepared from natural raw materials. AgVO3 nanowires, prepared by the coprecipitation method, were added in different amounts (1, 3, and 5 wt.%) to a DP mass with the initial composition of 80 wt.% feldspar, 15 wt.% quartz, and 5 wt.% kaolin, obtained by sintering the mixture at 1300 °C. The structural and morphological properties of AgVO3 and DP were investigated by X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), and transmission electron microscopy (TEM). The results showed the formation of α-AgVO3 nanowires coated with semispherical metallic silver nanoparticles. Moreover, α-AgVO3 additions do not influence the structural and morphological properties of DP, with the presence of Ag and V clearly identified in the DP with the α-AgVO3 addition. Our findings highlight the potential of this novel material for use in various dental applications. Future studies need to establish the antibacterial properties of the prepared dental material.

Abstract Purpose This study aimed to assess the diagnostic accuracy of cone-beam computed tomography (CBCT) and digital intraoral radiography for the detection of proximal caries adjacent to amalgam, e.max porcelain, and metal-ceramic restorations (MCRs). Materials and methods Parallel intraoral radiographs were obtained from 40 posterior teeth using PSP sensors. To obtain CBCT scans, the teeth were first radiographed alone, and were then positioned next to a tooth with an amalgam restoration, MCR, and e.max porcelain crown, and radiographed again. Two blinded observers scored radiographs using a four-point scale (0: absence of proximal caries, 1: enamel caries, 2: carious lesion extending to the outer half of dentin, 3: carious lesion extending to the inner half of dentin). Tooth sections were made, and the grade of caries was determined under a light microscope at x12 magnification. The sensitivity, specificity, and accuracy of CBCT and intraoral radiographs were then calculated. Results Artifact-free CBCT scans and intraoral radiographs had the highest diagnostic accuracy (0.826 and 0.657, respectively) while CBCT images of the teeth next to the amalgam restorations (0.526) had the lowest accuracy. The diagnostic accuracy of CBCT images of the teeth next to the porcelain crowns and MCRs was 0.613 and 0.601, respectively. Conclusion Artifact-free CBCT images had higher diagnostic accuracy than intraoral radiography for the detection of all grades of proximal caries. The diagnostic accuracy of CBCT images of teeth adjacent to amalgam, porcelain, and MCRs was lower compared to intraoral radiographs and artifact-free CBCT images.

Abstract Objectives The objective of this in vitro study was to evaluate the shear bond strength between the ceramic veneer and additively manufactured titanium with different surface treatments, and to compare with milled titanium. Also, to characterize the surface and the presence of an α‐case layer of additively manufactured and milled titanium. Material and Methods Sixty additively manufactured titanium grade 23, and 20 milled titanium grade 4 cylindrical specimens were divided into four groups based on surface treatments, air‐particle abrasion and grinding. After ceramic veneering half of each group were thermocycled. The bond strength was analyzed using a shear bond strength test. The surfaces were analyzed using interferometry and scanning electron microscopy. Results The grinding procedure and air‐particle abrading pressure had no significant effect on the shear bond strength (p = .264 and p = .344). Thermocycling showed a tendency towards an effect but not significant (p = .052). The group with the highest air‐abrading pressure showed the highest surface roughness. No presence of an α‐case layer was detected in any of the groups. Conclusion Additively manufactured titanium grade 23 may be veneered with ceramics without prior grinding of the surfaces.

Porcelain fused to metal (PFM) is commonly used in dental restorations but is prone to fractures. Packable resin composites, influenced by various surface treatments like hydrofluoric acid, serve as alternatives. The acid treatment's specifics affect the porcelain's microstructure. Recently, ceromer resin composites have been introduced for indirect restorations. The purpose of this study is to determine the differences in packageable resin composites and ceromers as dental restorative materials. Cylindrical dental feldspathic porcelain was used, while the hydrofluoric acid was applied on the surface of the dental porcelain. The adhesive behaviours were measured, and the determination of the relationship between the timing effects and resin composites was carried out via statistical analysis. The atomic force microscopy (AFM) characterizations were performed to determine the surface roughness of restorative technique. The results showed that there were differences in packable resin composites and ceromers, in which every treatment times showed relationship to the adhesive behaviours on the cohesive fractures. The average value of adhesive strengths of packageable resin composites and ceromers respectively accounted for 2.73±1.69 MPa and 4.43±2.43 MPa. Statistical results showed that the highest adhesive strength was found in the 4-minutes of etching time due to more and deeper pores in accordance with AFM results, indicating easier penetration of silane as coupling agents and repairing materials. The conclusion of this study is that as the time of etching of hydrofluoric acid in porcelain increases, the value of the adhesive strength of the restorative material increases with a higher ceromer value than packable. [ABSTRACT FROM AUTHOR]

Background: This study aims to investigate the color stability of feldspathic porcelains with different concentrations of silver nanoparticles (AgNPs). Materials and Methods: In this experimental study, feldspathic porcelain disks with AgNPs of 0 parts per million (ppm), 250 ppm, and 500 ppm were used (sample size = 180). These ceramic discs were subjected to thermocycling in tea, orange juice, and artificial saliva.The optical parameters of disks were measured before and after being immersed in the solutions. Then, the color change (ΔE 00) of the samples was measured by using the CIEDE 2000 formula. The data were analyzed by one-way analysis of variance (ANOVA) and Tukey's post hoc test. The level of significance was determined to be 0.05. Results: The results of the ANOVA test show that there was a significant difference in ΔE 00 (P < 0.05).The maximum ΔE 00 was visible in the samples with AgNPs 0 ppm that were exposed to orange juice, and the minimum ΔE 00 was related to the disks with AgNPs 500 ppm in artificial saliva. Conclusion: Based on the results of this study, adding AgNPs to feldspathic porcelain increases the color stability of the ceramic discs. [ABSTRACT FROM AUTHOR]

Purpose: This systematic review aimed to evaluate the medium-term (3-year) overall survival and success rates, marginal bone loss and different biological parameters displayed with one-piece zirconia implants. Materials and methods: Electronic searches were conducted of the MEDLINE (via PubMed), Scopus (Elsevier), Cochrane Library (Wiley) and Web of Science (Clarivate Analytics) databases and manual searching was also performed for relevant articles published up to 14 November 2022. The review included human studies with a minimum of 10 subjects and/or 20 implants and with a follow-up period of at least 3 years after implant placement. Results: Twelve studies met the inclusion criteria and were included for analysis, giving a total of 1,621 one-piece zirconia implants. Eleven studies were included to perform a meta-analysis of survival rates, and six for success rates and marginal bone loss. The survival and success rates at the 3-year follow-up were 94.4% (95% confidence interval 90.4%–98.4%; P < 0.001) and 91.6% (95% confidence interval 84.2%–98.9%; P < 0.001), respectively, and marginal bone loss was 0.231 mm (95% confidence interval 0.190–0.272; P < 0.001). Conclusions: One-piece zirconia implants appear to be a reliable option for restoring missing teeth, obtaining an implant survival rate of 94.4% and a success rate of 91.6% after a follow-up period of at least 3 years. Moreover, the results showed acceptable rates of marginal bone loss and adequate biological parameters. [ABSTRACT FROM AUTHOR]

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Purpose: This study aimed to assess the diagnostic accuracy of cone-beam computed tomography (CBCT) and digital intraoral radiography for the detection of proximal caries adjacent to amalgam, e.max porcelain, and metal-ceramic restorations (MCRs). Materials and methods: Parallel intraoral radiographs were obtained from 40 posterior teeth using PSP sensors. To obtain CBCT scans, the teeth were first radiographed alone, and were then positioned next to a tooth with an amalgam restoration, MCR, and e.max porcelain crown, and radiographed again. Two blinded observers scored radiographs using a four-point scale (0: absence of proximal caries, 1: enamel caries, 2: carious lesion extending to the outer half of dentin, 3: carious lesion extending to the inner half of dentin). Tooth sections were made, and the grade of caries was determined under a light microscope at x12 magnification. The sensitivity, specificity, and accuracy of CBCT and intraoral radiographs were then calculated. Results: Artifact-free CBCT scans and intraoral radiographs had the highest diagnostic accuracy (0.826 and 0.657, respectively) while CBCT images of the teeth next to the amalgam restorations (0.526) had the lowest accuracy. The diagnostic accuracy of CBCT images of the teeth next to the porcelain crowns and MCRs was 0.613 and 0.601, respectively. Conclusion: Artifact-free CBCT images had higher diagnostic accuracy than intraoral radiography for the detection of all grades of proximal caries. The diagnostic accuracy of CBCT images of teeth adjacent to amalgam, porcelain, and MCRs was lower compared to intraoral radiographs and artifact-free CBCT images. [ABSTRACT FROM AUTHOR]

Feasibility investigation of natural teeth shades replication on dental prosthetics fabricated via functionally graded additive manufacturing (FGAM) using combination of feldspathic porcelain (FP) and yttrium aluminum garnet cerium (Y 3 Al 5 O 12: Ce, YAG:Ce) as a promising esthetic restoration option. Color-graded feldspathic crown fabrication parameter through FGAM method was comprehensively examined from the slurry rheology, cure depth, debinding to sintering temperature. Effect of light absorbent also checked towards overcuring reaction during UV exposure by the shape comparison. Lastly, the flexural bending strength measured following ISO 6872:2015 to assure the applicability. Applying the studied parameter, natural teeth shades then imitated and investigated by alteration of FP and FP + 0.1 wt% YAG:Ce (Y-FP). Generated color across the structure captured through mobile camera, interpreted through the CIELAB coordinate and the gradation confirmed by the color differences (ΔE 00) calculated using CIEDE2000 formula. Parameter study indicated that 70 wt% of FP slurry with 3 wt% dispersant and 0.2 wt% light absorbent is favored. It produces excellent flowability in our FGAM system with less overcuring justified by edge margin reduction from 95.65° to 90.00° after UV exposure on rectangle shapes masking. The obtain structure also offers adequate flexural bending strength of 106.26 MPa (FP) and 101.36 MPa (Y-FP) after sintering at 780 °C. This validated the materials as class 2 dental prosthetics citing ISO 6872:2015. Color gradation was verified by the yellow b* value reduction (14.8 to −3.33) as it shifted from cervical to incisal area while ΔE 00 further affirmed the differences from each segment in comparison with the FP and Y-FP. Color gradation was successfully replicated by FP and YAG:Ce composition shift via FGAM technique. This result highlights the potential of FGAM as an alternative for fabricating dental prosthetics with high efficiency and improved esthetic appeal. [Display omitted] [ABSTRACT FROM AUTHOR]

Background and Objective: This study aimed to compare the surface finish of milled leucite-reinforced ceramics polished with ceramic and composite polishing systems based on the manufacturers' recommendations. Materials and Methods: Sixty subtractive computer-aided manufactured (s-CAM) leucite-reinforced glass-ceramic specimens (IPS-Empress-CAD) were assigned into six groups: no polishing, a ceramic polishing kit, and four composite kit groups. The roughness average (Ra) was evaluated in microns using a profilometer, and scanning electron micrographs were obtained for qualitative analysis. A Tukey HSD posthoc test (α = 0.05) was used to determine significant intergroup differences. Results: After surface evaluation of the ceramics, the Ra values of the polishing systems ranked OptraFine (0.41 ± 0.26) < Enhance (1.60 ± 0.54) < Shofu (2.14 ± 0.44) < Astropol (4.05 ± 0.72) < DiaComp (5.66 ± 0.62) < No Polishing (5.66 ± 0.74). Discussion: Composite polishing systems did not provide as smooth surfaces as the ceramic polishing kit for CAD-CAM leucite-reinforced ceramics. Thus, using ceramic polishing systems, polishing leucite ceramics is recommended, whereas composite polishing systems should not be considered as an alternative for use in minimally invasive dentistry. [ABSTRACT FROM AUTHOR]

The main disadvantage of conventional zirconia is its high opacity. Depending on different conditions, especially the content of the yttrium stabilizer, it is possible to circumvent this issue, in view of this, several generations of yttrium stabilized zirconia were developed seeking to combine the robustness of zirconia with the aesthetics of porcelain veneers. The present work aimed to carry out an analysis on how the increase or decrease in the percentage of yttrium in the composition of monolithic zirconia can influence their properties, especially with regard to translucency. This study was carried out through a review in the Scielo, PubMed and Google Scholar databases with articles published between 2008 and 2021. In this way, it was concluded that the higher content of Y2O3 tended to increase the amount of isotropic cubic phase present and reduce the amount of birefringent tetragonal phase in ZrO2 together with a minimization of light scattering by secondary phases, leading to increased translucency and aging resistance. As yttrium oxide increases, zirconia grain sizes tend to increase as well, and translucency may improve with increasing grain size. Toughness and fracture toughness can be sacrificed considerably.

Background and Aim : One of the main reasons for the failure of metal-ceramic restorations is insufficient bond strength between porcelain and metal, which depends on various factors, including the manufacturing method. The purpose of this study was to evaluate the effect of manufacturing method on bond strength of porcelain to titanium substructure made by EBM or Milling method. Materials and methods: In this in-vitro study two groups comprised of twenty metal bars each were prepared with EBM or Milling method. first a resin bar was molded into standard ISO:9693 dimensions of 25 mm × 3 mm × 0.5 mm. then it scanned and Ten bars from each group were manufactured using milling device from titanium disks or from an EBM device from Ti-6Al-4Va titanium alloy. bars were sandblasted with 110 μm aluminum oxide particles and were impregnated with bonding agent before the application of 1/1 mm of porcelain onto 8 mm × 3 mm rectangular area in the center of each bar porcelain. Afterwards, bond strengths of the samples were assessed using 3-point bending test with a Universal Testing Machine. Statistical analysis was performed using T-test and a significant level of 0.05 was considered Results: The mean bond strength of EBM group (34.36±3.67MPa) was lower than Milling group (46.52±4.34 MPa) and there was statistically significant difference between groups (p-value<0.001). Conclusion: Bond strength of EBM-manufactured samples were lower than milled group while both groups exceed the minimum requirement of bond strength for metal-ceramic restoration according to ISO9693. [ABSTRACT FROM AUTHOR]

Tooth reduction guides allow clinicians to obtain the ideal space required for ceramic restorations. This case report describes a novel design (CAD) for an additive computer-aided manufactured (a-CAM) tooth reduction guide with channels that permitted access for the preparation and evaluation of the reduction with the same guide. The guide features innovative vertical and horizontal channels that permit comprehensive access for preparation and evaluation of the reduction with a periodontal probe, ensuring uniform tooth reduction and avoiding overpreparation. This approach was successfully applied to a female patient with non-carious lesions and white spot lesions, resulting in minimally invasive tooth preparations and hand-crafted laminate veneer restorations that met the patient's aesthetic demands while preserving tooth structure. Compared to traditional silicone reduction guides, this novel design offers greater flexibility, enabling clinicians to evaluate tooth reduction in all directions and providing a more comprehensive assessment. Overall, this 3D printed tooth reduction guide represents a significant advancement in dental restoration technology, offering clinicians a useful tool for achieving optimal outcomes with minimal tooth reduction. Future work is warranted to compare tooth reductions and preparation time for this guide to other 3D printed guides. [ABSTRACT FROM AUTHOR]

Dental porcelain was produced by mixing feldspar, silica, kaolin and bone ash by varying the contents of feldspar and silica. The processing steps include milling, sieving, pressing/shaping, drying, and sintering while the characterisation techniques were Hardness, Compressive strength, X-ray diffraction, Scanning electron microscopy and Fourier Transform Infrared (FTIR). The mixture was subjected to temperatures of 1100 and 1200 °C in a sintering furnace. The chemical composition was determined using X-ray fluorescence and they confirm that SiO2 and Al2O3 are the two major constituents in feldspar and kaolin while CaO is the major constituent in bone ash. For samples sintered at 1200°C, the X-ray diffraction showed that some glass phase possibly consisting of hedenbergite, ilmenite and silica were formed while crystalline phases namely microcline and sanidine were obtained for samples sintered at 1100°C. The morphology of the grains revealed that samples sintered at 1200°C had some hexagonal silica crystals while flakes f different sizes were obtained for samples sintered at 1100°C. Hardness values between 262 and 536 BHN, compressive modulus values ranging from 219 MPa to 324 MPa and linear shrinkage values between 6.34 and 7.6% were obtained. The batches of different compositions with ranges: quartz (silica) (15-25%), feldspar (70-80%), kaolin (Edda/Bauchi) (4%) and bone ash (1%) were fired at 1100, 1200°C, and the developed properties were tested. The sample with 70 wt.% of feldspar, 25 wt.% silica, 4 wt.% of Bauchi clay, and 1 wt.% bone ash sintered at 1200°C gave the best properties and has the potential to be used in dental restoration. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to investigate the influence of the quantity and positioning of feldspathic ceramic specimens inside the furnace on their flexural strength and translucency. The tested hypotheses were that the arrangement of specimens in the furnance would not influence 1) the translucency or 2) the biaxial strength of the porcelain. Methods: Ninety porcelain specimens were made (1.2 mm thickness and 13.5 mm diameter) and assigned into two main groups (n=15): G1 group - 15 firing cycles containing only one specimen each, always at the center of the refractory; and G5 group - 15 firing cycles containing five specimen each, where one specimen was at the center of the refractory and four specimens positioned equidistantly on the periphery. The translucency test was performed using a spectrophotometer, followed by the flexural strength test, according to ISO 6872:2015. T-student test was performed for both the mechanical and optical obtained data. Results: The flexural strength of the porcelain was not affected by the positioning (center x periphery) of the specimens inside the furnace (p =0.08), but the translucency was affected (periphery > center; p =0.009). Regarding to the number of feldspathic ceramic specimens, the biaxial flexural strength was affected (p =0.025), as well as the translucency (p <0.05). Conclusion: A higher quantity of feldspathic ceramic specimens for each firing cycle decreased its biaxial flexural strength and translucency. Also, specimens positioned at the center of the refractory became less translucent than those positioned at the periphery. [ABSTRACT FROM AUTHOR]

Abstract Objective The purpose of this study is to evaluate the color changes of lithium disilicate ceramics when cemented with different brands of cement by varying the thickness of the ceramic. Materials and Methods Forty ceramic discs, shade A2, were fabricated with 0.5 and 0.8 mm thickness. Forty composite resin discs, shade A3, were also produced. The ceramic samples were cemented to the composite resin discs, with two colors of resin cement, Neutral and Warm. A spectrophotometer evaluation was made. Translucency and color change analysis was performed by calculating the ΔE. A two‐way analysis of variance test and multiple comparisons were performed using the Bonferroni method with a 95% confidence interval. Results There are statistically significant differences between the two ceramic thicknesses with different brands of cement (p

Background: This systematic review and meta-analysis aimed to evaluate the wear of the antagonist tooth in ceramic restorations. Material and methods: This study was carried out based on Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) recommendations; it was also registered in PROSPERO (register number: CRD42022316252). Three databases were consulted in the literature search, Embase, Scopus, and Web of Science. The citation searching was conducted by two researchers independently. The clinical studies that evaluated wear in antagonist teeth concerning ceramic restoration were included. Twelve articles were selected after eliminating duplicates ones and applying the inclusion criteria, and two were chosen through citation. Fourteen articles were considered for the qualitative and quantitative analysis (meta-regression and meta-analysis). Results: The mean linear wear of the antagonist tooth in relation to feldspathic was 8.914 μm, for lithium disilicate it was 0.018 μm, and for zirconia it was 0.257 μm. The mean volumetric wear of the antagonist tooth in relation to feldspathic was 0.273 mm3, for hybrid ceramic it was 0.030 mm3, for lithium disilicate it was 0.018 mm3, and for zirconia it was 0.014 mm3. The mean natural tooth wear was 0.7974 μm per month. Tooth wear caused by zirconia at six months was 31.755 μm, at 12 months it was 24.648 μm, and at 24 months it was 20.662 μm. Conclusions: Feldspathic produces greater wear of the antagonist tooth from ceramic restorations linearly and volumetrically. In addition, zirconia generates the least wear that will decrease over time, and it will be equal to or less than the natural wear in the tooth. [ABSTRACT FROM AUTHOR]

Purpose: is to investigate the longevity, survival and complications rate of laminate veneers produced from Feldspathic and Glass Ceramic. Materials and Methods: Literature search was conducted, using electronic MEDLINE database, relevant references, citations and hand search. Inclusion Criteria were human cohort studies (prospective and retrospective) reporting on survival and complications of ceramic veneers fabricated of Feldspathic and Glass ceramic with a minimum follow up of 2.5 years. The search period spanned from 01.01.2000 up to 30.11.2018. Of the 522 articles identified, 110 went throw full text screening for eligibility and 20 studies were included in our study. Survival rate were assessed. Complication rates for Laminate veneers most common complications were in subgroups calculated using forest plot. Comparison between complication of poor marginal adaptation and fracture of feldspathic and Glass Ceramic Veneers were conducted using random effect models. Results: The mean observation time of the veneers 8.2 years. Survival rate of both materials was over 90%. The most frequent complications reported were: poor marginal adaptation 4% (95% CI: 2% to 8%), fracture 4% (95% CI: 3% to 6%) and marginal discoloration 9% (95% CI: 5% to 15%). There was no statistically significant difference in the complication rates of poor marginal adaptation and fracture between the subgroups of both materials. Clinical significance: Complication rate of both Feldspathic and Glass Ceramic Veneers was similar. Survival rate was remarkably higher in glass ceramics, but was still considered to be satisfactory in both materials, which leads us to conclude that porcelain laminate veneers are reliable treatment methods. [ABSTRACT FROM AUTHOR]

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Background: For all-ceramic restorations to last a long time, the ceramic veneering and substructure need to have a strong sufficient bond. This research compared how two different surface treatments affected the tensile and shear bond strengths of zirconium-reinforced lithium silicate and porcelain (Suprinity). Materials and Methods: A total of 120 samples were divided into three groups at random: control (no surface treatment), aluminium oxide sandblasting, Erbium, Chromium-doped Yttrium, Scandium, Gallium, and Garnet (Er, Cr: YSGG) laser irradiation, and 60 samples to evaluate tensile bond strength and 60 samples to evaluate shear bond strength. By using one-way ANOVA and the post-hoc Tukey's test, the tensile and shear bond strength between Suprinity and porcelain (VITA VM 11) was analyzed in all groups. Results: The maximum and minimum tensile bond strength was seen in sandblasting group (7.86 ± 2.22 Mpa) and control group (4.88 ± 1.58 Mpa), respectively (P < 0.001). The amount of shear bond strength in the laser group, sandblast group, and control group was (5.16 ± 1.66 Mpa), (5.00 ± 1.34 Mpa), (4.39 ± 1.54 Mpa) respectively (P = 0.252). In tensile and shear bond strength tests, most failures were cohesive in VITA VM 11 layering porcelain (65.0% vs. 66.7%) followed by mixed failures (33.3% vs. 20%). Conclusion: Suprinity and layering porcelain produced higher tensile bonds as a result of Al2O3 sandblasting and Er, Cr: YSGG laser irradiation. While no pure adhesive failure was seen, cohesive failure was predominant. [ABSTRACT FROM AUTHOR]

Tooth enamel wear occurs because of daily mastication and occlusion. This study investigated the wear behavior of bovine teeth against aesthetic restorative materials in vitro. Abrader specimens were fabricated using four tooth-colored restorative materials (zirconia, lithium disilicate glass ceramic, dental porcelain, and resin composite), with bovine tooth enamel as a control. Flattened bovine tooth enamel was used as the substrate specimen. These materials were characterized by Vickers hardness tests and surface roughness measurements. Two-body wear tests between the abrader and substrate specimens were performed, and the worn topographies were evaluated using a contour-measuring instrument and 3D laser microscope. The restorative materials and bovine tooth enamel had similar surface roughness but different hardness and wear behaviors. Bovine teeth showed the largest wear in tooth–tooth contact as the abrader and substrate specimens. Compared to bovine teeth, zirconia, lithium disilicate glass ceramic, and dental porcelain showed greater hardness and less wear on their surfaces, and less substrate wear of the opposite tooth enamel. The lowest hardness resin composite showed intermediate wear on its surface, resulting in the lowest substrate wear. Accordingly, dentists should pay attention to the selection of restorative materials to reconstruct their morphologies owing to different wear behaviors. [ABSTRACT FROM AUTHOR]

Introduction: Dental porcelain is fired at a high temperature inside the furnace and subsequently glazed for intraoral use as a restoration. There is no clarity on the correlation between physical properties of porcelain and its surface finishing techniques. Aim: To evaluate surface hardness and fracture toughness of feldspathic porcelain with different porcelain surface finishing methods. Materials and Methods: This in-vitro descriptive study was conducted between November 2018 and August 2019 at Department of Prosthodontics, Ragas Dental College and Hospital with 40 samples of Nickel Chrome (Ni Cr) alloy specimens, with addition of porcelain. The sample were divided into four groups S1: Unpolished, S2: Polished, S3: Autoglazed, S4: Add-on glaze according to the finishing procedures used with each group containing ten samples. All samples were tested for surface hardness and Fracture toughness and were subjected to One way ANOVA, Bonferroni posthoc tests and Statistical Package of the Social Sciences (SPSS) California, USA. Results: Mean value of fracture toughness (in MPa1/2) for 0.2 kg load was 0.729672 for S1, 1.187567 for S2, 0.89482 for S3, 1.324399 for S4. Mean value of surface hardness (in kg/mm2) for 1 kg load was 360.048 for S1, 519.166 for S2, 508.817 for S3, 527.916 for S4. Maximum deviation of 24.752 and error of 7.8273 was found in S4, least deviation of 10.77 and error of 3.4077 was found in S1 group. Conclusion: The glazed porcelain had the highest micro hardness and fracture toughness followed by polished porcelain and autoglazed porcelain. [ABSTRACT FROM AUTHOR]

Objective: To compare porcelain and metal repair done with both nanocomposite and conventional composite. Material and Methods: A total of 30 cylinders were fabricated from Porcelain (I), Porcelain fused to metal (II), and metal (III) substrate each. Control group (A) was bonded with conventional micro-hybrid composite and experimental group (B) was bonded with nanocomposite in a 2 mm thickness. All specimens were thermocycled and stored in distilled water at 37 °C for 7 days. A universal testing machine was used to measure the Shear bond strength (SBS). The difference between bond strengths of the groups was compared using an independent t-test. Results: In all three groups, the SBS was higher in the experimental group as compared to the control group. The use of nanocomposite of metal alloy presented maximum shear bond strength, followed by samples of porcelain fused to metal and finally porcelain, showing the lowest values of SBS. Conclusion: Porcelain and alloys bonded with nanocomposite exhibit enhanced adhesiveness as well as aesthetic and mechanical properties. This subsequently would translate into providing higher clinical serviceability and durability and hence a cost-effective and accessible repair option for human welfare.

Introduction: Dental porcelain is fired at a high temperature inside the furnace and subsequently glazed for intraoral use as a restoration. There is no clarity on the correlation between physical properties of porcelain and its surface finishing techniques. Aim: To evaluate surface hardness and fracture toughness of feldspathic porcelain with different porcelain surface finishing methods. Materials and Methods: This in-vitro descriptive study was conducted between November 2018 to August 2019 at Department of Prosthodontics, Ragas Dental College and Hospital, Tamil Nadu, India, with 40 samples of Nickel Chrome (NiCr) alloy specimens, with addition of porcelain. The sample were divided into four groups S1: Unpolished, S2: Polished, S3: Autoglazed, S4: Add-on glaze according to the finishing procedures used with each group containing 10 samples. All samples were tested for surface hardness and Fracture toughness and were subjected to One-way Analysis of Variance (ANOVA), Bonferroni posthoc tests and Statistical Package of the Social Sciences (SPSS) California, USA. Results: Mean value of fracture toughness (in MPa1/2) for 0.2 kg load was 0.729672 for S1, 1.187567 for S2, 0.89482 for S3, 1.324399 for S4. Mean value of surface hardness (in kg/mm2) for 1 kg load was 360.048 for S1, 519.166 for S2, 508.817 for S3, 527.916 for S4. Maximum deviation of 24.752 and error of 7.8273 was found in S4, least deviation of 10.7760 and error of 3.4077 was found in S1 group. Conclusion: The glazed porcelain had the highest micro hardness and fracture toughness followed by polished porcelain and autoglazed porcelain.

Background and Objective: This study aimed to compare the surface finish of milled leucite-reinforced ceramics polished with ceramic and composite polishing systems based on the manufacturers’ recommendations. Materials and Methods: Sixty subtractive computer-aided manufactured (s-CAM) leucite-reinforced glass-ceramic specimens (IPS-Empress-CAD) were assigned into six groups: no polishing, a ceramic polishing kit, and four composite kit groups. The roughness average (Ra) was evaluated in microns using a profilometer, and scanning electron micrographs were obtained for qualitative analysis. A Tukey HSD posthoc test (α = 0.05) was used to determine significant intergroup differences. Results: After surface evaluation of the ceramics, the Ra values of the polishing systems ranked OptraFine (0.41 ± 0.26) < Enhance (1.60 ± 0.54) < Shofu (2.14 ± 0.44) < Astropol (4.05 ± 0.72) < DiaComp (5.66 ± 0.62) < No Polishing (5.66 ± 0.74). Discussion: Composite polishing systems did not provide as smooth surfaces as the ceramic polishing kit for CAD-CAM leucite-reinforced ceramics. Thus, using ceramic polishing systems, polishing leucite ceramics is recommended, whereas composite polishing systems should not be considered as an alternative for use in minimally invasive dentistry.

The surface management of dental porcelain for different dental applications is an important procedure in dentistry. On one hand, we need rough and course surfaces for bonding purposes, and on the other hand, the surface of the dental porcelain needs to be glazed to acquire the best aesthetic appearance and strength. As pores and voids scatter the light and decrease the translucency and may initiate chipping off the material from high-stress points. Mainly the consolidation of the porcelain and elimination of porosity is achieved by sintering. The reduction of porosity is more dependent upon temperature than on time. Therefore, it is possible to attain optimum glazing at a comparatively faster rate by using energy delivery through laser irradiation. In this study, Nd: YAG laser is irradiated on porcelain samples in pellet form. After laser irradiation, a glazed and mechanically improved porcelain surface is obtained with no considerable change in its microstructure. [ABSTRACT FROM AUTHOR]

• Fatigue behavior of lithium disilicate crowns depends on cement viscosity and topographical changes from ceramic treatment. • Superior fatigue failure results are obtained with HF/silane + High viscosity; or Etch & Prime + Low viscosity. • The defects at the ceramic intaglio surface need to be filled by the luting agent for fatigue improvements. • The luting agent viscosity play a crucial role for filling the defects. • HF etching induced a more pronounced topographical alteration compared to the Etch & Prime agent. To assess the effects of a resin cement in high and low viscosity and distinct conditioning of the intaglio surface of lithium disilicate glass-ceramic crowns on fatigue performance of the crowns. Prosthetic preparations (full-crown) in resin epoxy and crowns in lithium disilicate glass-ceramic were machined and allocated considering 2 factors (n = 10): "surface treatment" (HF – 5% hydrofluoric acid etching, followed by silane application; or E&P–self-etching ceramic primer) and "resin cement" (high or low viscosity). The preparations were etched with 10% hydrofluoric acid and an adhesive was applied. The intaglio surfaces of the ceramic crowns were treated as aforementioned (HF or E&P) and luted with high or low viscosity. The bonded sets were subjected to fatigue testing (step-stress approach: initial load of 200 N, step-size of 50 N, 10,000 cycles/step, 20 Hz) and complementary analyses (fractographic, topographic, and cross-sectional bonded interfacial zone analyses) were performed. Treatment with HF and silane with high viscosity resin cement (955 N/156,000 cycles) and E&P with low viscosity resin cement (1090 N/183,000 cycles) showed the best fatigue performance (statistical similarity between them). The failures originated from defects of the cement-ceramic interface, and the HF treatment induced a more pronounced topographical alteration. Distinct topographical patterns from the HF and E&P treatments induced better fatigue results for the specific viscosity of the resin cement. Therefore, the fatigue performance depended on the existing topography, type of intaglio surface's defects/irregularities after surface treatment, and how the luting agent filled the irregularities. [ABSTRACT FROM AUTHOR]

Objectives: This study evaluated the effect of deep margin elevation (DME) and restorative materials (leucite-reinforced glass–ceramics [C] vs. indirect resin composite [R]) on the fatigue behavior and stress distribution of maxillary molars with 2-mm deep proximal margins restored with MOD inlay. Methods: Fifty-two extracted human third molars were randomly assigned into four groups (n = 13): C; DME + C; R; and DME + R. Inlays were fabricated in CAD-CAM and bonded to all teeth. The fatigue behavior was assessed with the stepwise stress test (10,000 cycles/step; step = 50 N; 20 Hz; initial load = 200 N). Fatigue failure loads and the number of cycles were analyzed with 2-way ANOVA and Tukey's test (p < 0.05) and Kaplan–Meier survival plots. The stress distribution was assessed with finite element analysis. The models were considered isotropic, linear, and homogeneous, and presented bonded contacts. A tripod axial load (400 N) was applied to the occlusal surface. The stress distribution was analyzed with the maximum principal stress criterion. Results: For fatigue, there was no difference for DME factor (p > 0.05). For the material factor, the load and number of cycles for failure were statistically higher in the R groups (p < 0.05). The finite element analysis showed that resin composite inlays concentrated more stress in the tooth structure, while ceramic inlays concentrated more stress in the restoration. Non-reparable failures were more frequent in the resin composite inlays groups. Conclusions: DME was not negative for fatigue and biomechanical behaviors. Resin composite inlays were more resistant to the fatigue test, although the failure mode was more aggressive. Clinical significance: DME does not impair mechanical behavior. Resin composite inlays failed at higher loads but with a more aggressive failure mode. [ABSTRACT FROM AUTHOR]

Amaç: Bu çalışmanın amacı, estetik dental uygulamalardan biri olan porselen laminate veneer uygulamaları hakkındaki YouTube videolarının içeriğini değerlendirmektir.Gereç ve Yöntem: ‘Porselen laminate veneer’ anahtar sözcükleri kullanılarak YouTube’da sistematik bir arama yapıldı. Videolar yükleyiciye göre sınıflandırılıp, bilgi içerikleri değerlendirildi. Video bilgileri-kalite indeksi aracılığıyla video kalitesi hesaplandı. Ayrıca videoların etkileşim ve görüntülenme oranları da analiz edildi. Elde edilen veriler, istatistiksel olarak incelendi ve anlamlılık p

Resin cement and preheated restorative resin composite may be used for luting laminate veneers. The main advantage of resin composite is increased wear resistance, which could lead to better marginal performance in long term. This article reports a clinical treatment with feldspar laminate veneers luted to the maxillary teeth with preheated resin composite in a private practice. Case was finalized in May 2009 and followed by 10 years. Excellent clinical service and remarkable long-lasting marginal integrity were observed after 123 months. Scanning electron microscopy analysis showed no wear, gaps, or ditching at the margins. Restorative margins showed a smooth transition between ceramic and tooth with no signs of degradation. Preheated resin composite for luting ceramic laminate veneers may be considered an excellent clinical option.

A 28-year-old male patient reported with a chief complaint of poor aesthetic due to missing tooth in upper front region of jaw since two years. Extraoral examination [Table/Fig-1] showed squarish facial form, straight profile and adequate lip support with thin long competent lips. Intraoral examination showed Ellis class III fracture with maxillary Right Central Incisor (11) [Table/Fig-2]. As the amount of tooth structure was less and it was carious so it was decided to extract 11. The site was allowed to heal for three weeks. The patient did not agreed for the implant placement due to the time and cost factor. So a minimally invasive all ceramic maryland bridge was planned to restore missing maxillary right central incisor. Shade selection of A2 was done with maxillary left central incisor as reference. A diagnostic impression was made using irreversible hydrocolloid [Table/Fig-3] and diagnostic mock-up was done [Table/Fig-4] followed with mock trial for patient approval [Table/Fig-5]. Minimal tooth preparation on the lingual surfaces of the abutments 12 and 21 was done using deep chamfer 1.0 diamond bur and finished using finishing bur. Preparations were not extended beyond the linguo-proximal line angles on the abutments. Lingual preparation ended 0.5 mm from the incisal edge and a feather finish line was prepared 0.5 mm supragingivally [Table/Fig-6] [1]. Single step final impression was made using addition silicone (flexceed). Final wax up was done on the final cast for all ceramic lithium disilicate maryland bridge [Table/Fig-7]. Lithium disilicate bridge was fabricated using pressable technique [Table/Fig-8]. Shade, aesthetic, fit and occlusion was evaluated during bisque trial. The final finishing and polishing was done. Following bonding protocol was followed for lithium disilicate maryland bridge with 12, 21. Ceramic was etched with 10% of hydrofluoric acid for 10 seconds and teeth were etched using 37% of phosphoric acid for 20 seconds followed by cleaned and washed under water and air dried giving a white frosty appearance [Table/Fig-9] [2]. Followed by application of bonding agent to the teeth and bridge and light cured using light curing unit [Table/Fig-10]. Following this final cementation of maryland bridge with 12, 11 and 21 was done using variolink resin cement [Table/Fig-11]. The following post cementation instructions were given to the patient. Do not bite from the front teeth as the prosthesis can get fracture. Oral hygiene instructions to be followed of 45o angle brushing twice a day and flossing once a day to avoid getting a cavity or gum disease around your new prosthesis. Flossing is especially important in preserving the health of your bridge [3]. The patient follow-up was done at interval of 1 day, 1 week, 3 months and yearly; the prosthesis was in good condition [Table/Fig-12,13]. Implants fixed prosthesis, three unit fixed dental prosthesis, adhesive bridges, fibre reinforced prosthesis are various treatment options available for replacement of missing single anterior teeth. Implant is a surgical procedure and requires longer time, three unit fixed dental prosthesis requires more preparation of the abutment teeth, fibre reinforced prosthesis are temporary option to overcome these disadvantages a conservative treatment option of all ceramic lithium disilicate maryland bridge was chosen. The maryland bridge, also known as resin-bonded bridge can be used for anterior as well as for posterior single missing tooth as concluded by Gulati JS et al., [4]. A maryland bridge consists of a metal framework with porous surface and a porcelain tooth connected onto the front of the framework [5]. Advantages of maryland bridge are conservative, reversible, less trauma to pulp of abutment tooth, unaltered natural teeth and less periodontal irritation [6]. Disadvantages of maryland bridge are indicated for single missing tooth, colour change due to metal hue, debonding of metal wing and recementation [6]. To overcome the problems of metal wing and with the advancement in metal free materials we have opted for all ceramic pressable lithium disilicate maryland bridge (IPS e.max) which has increased strength, better retention and aesthetics as compared to metal adhesive bridges [7]. However, the failures can occurs in the form of debonding (78%), fracture (13%) as concluded by Balasubramanian GR in 2017 [8]. On two year follow-up the maryland bridge was in good condition without any signs of failure or fracture or debonding.

Objective: The purpose of this study is to evaluate the color changes of lithium disilicate ceramics when cemented with different brands of cement by varying the thickness of the ceramic. Materials and Methods: Forty ceramic discs, shade A2, were fabricated with 0.5 and 0.8 mm thickness. Forty composite resin discs, shade A3, were also produced. The ceramic samples were cemented to the composite resin discs, with two colors of resin cement, Neutral and Warm. A spectrophotometer evaluation was made. Translucency and color change analysis was performed by calculating the ΔE. A two‐way analysis of variance test and multiple comparisons were performed using the Bonferroni method with a 95% confidence interval. Results: There are statistically significant differences between the two ceramic thicknesses with different brands of cement (p <.001). In addition, using the translucency analysis it was found that there are statistically significant differences between the two ceramic thicknesses in both types of cement (p <.001). Conclusions: The use of different cementation materials on lithium disilicate ceramics appears to have little visible influence at the clinical level. Different ceramic thicknesses have a clinically visible influence on the final restoration color. [ABSTRACT FROM AUTHOR]

Introduction: The prevalence of using different esthetic methods increases the possibility of close contact between them with potential adverse interactions. This study aimed to compare the surface changes (microhardness and roughness) in two types of feldspathic porcelain after laser bleaching and post-bleach polishing. Methods: 12 standardized rectangular specimens were prepared for each porcelain group (conventionally layered and CAD-CAM milled). Vickers microhardness and roughness were evaluated before and after the bleaching procedure and after polishing. Data were statistically analyzed using repeated measures ANOVA and t test (P < 0.05). Results: The surface roughness of both groups increased significantly after laser bleaching (P < 0.001 for conventional and P = 0.004 for CAD-CAM porcelains). The polishing process reduced the roughness of both groups; the reduction was significant in conventional specimens (P = 0.020). The surface hardness values did not change significantly in the groups after bleaching and post-bleach polishing stages (P = 0.142). Generally, the average surface roughness of CAD-CAM specimens was significantly lower (P < 0.001), and the surface microhardness of the CAD-CAM group was significantly higher than conventional porcelains (P = 0.011). Conclusion: Laser bleaching significantly increased the surface roughness of feldspathic porcelains; however, it did not affect the surface microhardness significantly. Unlike CAD-CAM specimens, polishing significantly improved the surface smoothness of conventional porcelains. [ABSTRACT FROM AUTHOR]

Background: With the constantly increasing demand for metal‐free solutions in dental therapy, numerous ceramic restorations have found their way into everyday clinical practice, but long‐term clinical data are limited. Objective: The aim of this prospective clinical study was to evaluate three‐ and four‐unit fixed partial dentures in the posterior region made of zirconium dioxide frameworks veneered with feldspathic porcelain after 10 years in clinical use. Methods: Based on the two studies published in 2009 and 2012, in which the all‐ceramic FDPs were evaluated after 3 and 5 years of function, a clinical evaluation of a total of 17 restorations after 10 years with regard to their condition and long‐term stability was carried out in the course of this study. The restorations were fabricated using feldspathic ceramic‐veneered, yttria‐stabilised, tetragonal zirconium dioxide as the framework material. The data collection was based on modified CDA criteria and included, for example, the shape, shade, surface condition and the success and survival rates of the restorations. Results: The all‐ceramic prostheses embodied excellent biocompatibility and colour reproduction. As a result of an increased incidence of chipping fractures, the success rate was 60%. The survival rate, however, was 88.2%, as 2 of the 17 restorations were lost. Conclusion: All‐ceramic concepts for FDP constructions in the posterior region achieved satisfactory results in terms of durability after 10 years. The main problem was chipping, as has been generally recognised. Nevertheless, the materials were characterised by excellent aesthetics and biocompatibility, which ultimately makes them a good alternative to conventional restorative options. Trial registration: This study is registered in DRKS—German Clinical Trials Register with the register number DRKS00021743. [ABSTRACT FROM AUTHOR]

Objective: To compare porcelain and metal repair done with both nanocomposite and conventional composite. Material and Methods: A total of 30 cylinders were fabricated from Porcelain (I), Porcelain fused to metal (II), and metal (III) substrate each. Control group (A) was bonded with conventional microhybrid composite and experimental group (B) was bonded with nanocomposite in a 2 mm thickness. All specimens were thermocycled and stored in distilled water at 37 °C for 7 days. A universal testing machine was used to measure the Shear bond strength (SBS). The difference between bond strengths of the groups was compared using an independent t-test. Results: In all three groups, the SBS was higher in the experimental group as compared to the control group. The use of nanocomposite of metal alloy presented maximum shear bond strength, followed by samples of porcelain fused to metal and finally porcelain, showing the lowest values of SBS. Conclusion: Porcelain and alloys bonded with nanocomposite exhibit enhanced adhesiveness as well as aesthetic and mechanical properties. This subsequently would translate into providing higher clinical serviceability and durability and hence a cost-effective and accessible repair option for human welfare. [ABSTRACT FROM AUTHOR]

Objective: To assess the effects of coloring beverages on the color stability of two types of hybrid ceramics with different surface treatments. Material and Methods: 180 specimens of two hybrid ceramics (Vita Enamic and Mazic Duro) and a feldspathic ceramic (Vita Mark II) were prepared (n=60 in each group). Half of the discs in each group were glazed while the other was polished. The specimens were then divided into three subgroups and immersed in distilled water, carrot juice, and coffee. The overall color difference (∆E) was calculated based on CIE L*a*b* color space. Data were analyzed using three-way and one-way ANOVA; Tukey’s honest significant difference was also done for pairwise comparisons (α=0.05). Results: Vita Mark II specimens revealed less overall color changes compared to other groups. The ∆E of the glazed Vita Enamic specimens was greater than polished specimens following immersion in distilled water (p=0.03) and coffee (p=0.001), but it was not significant for carrot juice. The same results were obtained for polished Mazic Duro specimens. Relatively similar amounts of ∆E were recorded in polished and glazed subgroups of Vita Mark II. Conclusion: The ∆E of hybrid ceramics was higher than Vita Mark II. Polishing could be recommended for surface treatment of hybrid ceramics instead of glazing, saving time and facilitating the process. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the marginal adaptation of computer-aided designing and computer-aided machining (CAD/CAM) fabricated cobalt-chromium and zirconium-oxide-based ceramic crowns compared to those produced by a conventional method. Material and Methods: The study consists of three groups; 45 crowns fabricated from cobalt-chromium (CAD-CoCr) and 45 crowns manufactured from zirconium CAD/CAM technology (CAD-Z), and 45 control (C) which consists of conventional metal-ceramic crowns. The marginal discrepancies in vertical dimensions were assessed utilizing a microscope in four surfaces (mesial, distal, vestibular, and oral) for each crown. On completion of the microscopic evaluation, multivariate analysis of variance (MANOVA) was used to study the difference in the four surfaces, considered altogether. Two-way ANOVA revealed the effect of three systems used for gap measurements of each landmark. The differences observed were considered significant at p<0.05. Results: There were no differences in the four surfaces revealed by ANOVA in the three groups when considered altogether. Twoway ANOVA of each surface discovered no differences among all groups as well. Conclusion: The CAD/CAM crowns revealed a comparable and satisfactory marginal adaptation compared to conventional metal-ceramic crowns. [ABSTRACT FROM AUTHOR]