Randomized controlled pilot study assessing efficacy, efficiency, and patient-reported outcomes measures of chairside and labside single-tooth restorations.

OBJECTIVES: To test whether or not a chairside workflow (CHAIR) is similar to a labside workflow (LAB) in terms of efficacy (primary outcome) and efficiency (secondary outcome). MATERIAL AND METHODS: Eighteen subjects in need of a single-tooth restoration in the posterior region of the maxilla or mandible were consecutively recruited and randomly assigned to the CHAIR or LAB workflow. Patient-reported outcome measures (PROMs; efficacy) were assessed using a questionnaire with visual analog scale. The white AEsthetic score (WES) was applied to evaluate the AEsthetic outcome objectively. The clinical and laboratory time (efficiency) were recorded. Nonparametric methods were applied for the group comparisons. RESULTS: The overall median AEsthetic evaluation after treatment was 10 (interquartile range = IQR: 9.5-10) in group CHAIR and 10 (IQR: 9.5-10) in-group LAB (Mann-Whitney [MW] test p = 1.000). The WES amounted to 4 (IQR: 3-5) (CHAIR) and to 8 (IQR: 7-9) (LAB) (MW test p < 0.0001). The median total working time for the clinician in-group CHAIR was 49.9 min. (IQR: 40.9-63.7) and 41.4 min. (IQR: 37.2-58.2) in-group LAB (MW test p = 0.387). CONCLUSIONS: Subjective PROMs of single-tooth supported restorations fabricated in a CHAIR or LAB workflow led to similar scores of patients' satisfaction and a moderate negative correlation for the objective evaluation of the clinician in the LAB workflow. CLINICAL SIGNIFICANCE: PROMs can be considered a key element in the decision-making process for restoring single-tooth restorations. The patients' perception of AEsthetics was similar for the CHAIR or LAB workflows. The additional efforts undertaken with the LAB workflow did not result in a patient benefit when compared to a CHAIR workflow.

EPA Consensus Project Paper: Failure Rates of Direct Versus Indirect Single-Tooth Restorations. A Systematic Review and Meta-Analysis.

INTRODUCTION: The purpose of this systematic review and meta-analysis was to evaluate and compare the failure rates of direct and indirect restorations for single-tooth restorations. METHODS: A literature search was conducted by using electronic databases and relevant references for clinical studies on direct and indirect dental restorations with a follow-up of at least 3 years. The risk of bias was assessed with the ROB2 and the ROBINS- I tools. The I2 statistic was used for the assessment of heterogeneity. The authors reported summary estimates of annual failure rates of single-tooth restorations using a random-effects model. RESULTS: Of 1415 screened articles, 52 (18 RCTs, 30 prospective, 4 retrospective) met the inclusion criteria. No articles with direct comparisons were identified. No significant difference was found in the annual failure rates of single teeth restored with either direct or indirect restorations, which were calculated as 1% using a random-effects model. High heterogeneity was found, ranging from 80% (P⟨0.01) for studies on direct restorations to 91% (P⟨0.01) for studies on indirect restorations. Most of the studies presented some risk of bias. CONCLUSIONS: Annual failure rates were similar for direct and indirect single-tooth restorations. Further randomized clinical trials are needed to draw more definitive conclusions.

A 5-year randomized controlled trial comparing zirconia-based versus metal-based implant-supported single-tooth restorations in the premolar region.

OBJECTIVE: To compare 5-year biological, technical, aesthetic, and patient-reported outcomes of single-tooth implant-supported all-ceramic versus metal-ceramic restorations. MATERIALS AND METHODS: Thirty patients with 63 premolar agenesis participated in the 5-year follow-up. The prosthetic treatment on single-tooth implants was randomly assigned to all-ceramic crowns on zirconia abutments (AC = 31) or metal-ceramic crowns on metal abutments (MC = 32). All patients were recalled to clinical examinations at baseline, 1, 3, and 5 years after prosthetic treatments. Biological, technical, and aesthetic outcomes including complications were clinically and radiographically registered. The patient-reported outcomes were recorded using OHIP-49 questionnaire before treatment and at each follow-up examination. RESULTS: At the 5-year examination, the survival rate was 100% for implants and 100% for AC and 97% for MC crowns and abutments. The marginal bone loss after 5 years was minor and not significantly different (p = .056) between AC (mean: 0.3, SD: 1.1) and MC (mean: -0.1, SD: 0.4) restorations. The success rate of the implants based on marginal bone loss was 77.4% for AC- and 93.7% for MC restorations. The marginal adaptation was significantly better for MC than for AC restorations (p = .025). The aesthetic outcomes and patient-reported outcomes between AC and MC restorations were not significantly different. CONCLUSIONS: The biological, aesthetic and patient-reported outcomes for implant-supported AC and MC restorations were successful and with no significant difference after 5-years. The marginal adaptation of the MC crowns cemented on titanium abutments showed a significantly better fit than restorations based on zirconia crowns cemented on zirconia abutments.

Lithium disilicate posterior overlays: clinical and biomechanical features.

OBJECTIVES: The aim of this study was to evaluate the survival rate of lithium disilicate overlays in increasing occlusal vertical dimension (OVD) in the setting of minimally invasive techniques and the restoration thicknesses at different tooth sites. MATERIALS AND METHODS: This is an observational study evaluating 43 lithium disilicate overlays (Lithium IPS e.max Press, Ivoclar Vivadent) on 8 patients, prepared with minimally invasive criteria over a follow-up period between 19 to 45 months (mean follow-up of 32 months). Occlusal vertical dimension's increase was planned using occlusal treatment plan and diagnostic wax-up. Prior to adhesive cementation, restoration thicknesses were measured with a caliber. The survival rate was calculated by Kaplan-Meier analysis. RESULTS: Restoration survival rates at 32 months were 97.7%. One infiltration was observed, no cases of fracture occurred. The greatest thickness in monolithic restorations was detected in the cusp sides of teeth, whereas the thinnest was highlighted in the central fossa. The average amount of dental tissue removed during preparation was 0.98 mm in non-functional cusps, 0.88 mm in functional cusps, and 0.57 mm in the central fossa. CONCLUSIONS: Lithium disilicate posterior overlays show an excellent complication-free survival rate, and the material allows for conservative restorations with minimum thickness. CLINICAL RELEVANCE: Monolithic lithium disilicate overlays feature a satisfying 32-month survival rate. The technique allows to perform restorations with a minimal removal of dental tissue, while limiting fractures over time. Its esthetical performance is excellent.

Accuracy of single-tooth restorations based on intraoral digital and conventional impressions in patients.

OBJECTIVES: The purpose of this clinical study was to compare the marginal fit of dental crowns based on three different intraoral digital and one conventional impression methods. METHODS: Forty-nine teeth of altogether 24 patients were prepared to be treated with full-coverage restorations. Digital impressions were made using three intraoral scanners: Sirona CEREC AC Omnicam (OCam), Heraeus Cara TRIOS and 3M Lava True Definition (TDef). Furthermore, a gypsum model based on a conventional impression (EXA'lence, GC, Tokyo, Japan) was scanned with a standard laboratory scanner (3Shape D700). Based on the dataset obtained, four zirconia copings per tooth were produced. The marginal fit of the copings in the patient's mouth was assessed employing a replica technique. RESULTS: Overall, seven measurement copings did not fit and, therefore, could not be assessed. The marginal gap was 88 µm (68-136 µm) [median/interquartile range] for the TDef, 112 µm (94-149 µm) for the Cara TRIOS, 113 µm (81-157 µm) for the laboratory scanner and 149 µm (114-218 µm) for the OCam. There was a statistically significant difference between the OCam and the other groups (p < 0.05). CONCLUSION: Within the limitations of this study, it can be concluded that zirconia copings based on intraoral scans and a laboratory scans of a conventional model are comparable to one another with regard to their marginal fit. CLINICAL RELEVANCE: Regarding the results of this study, the digital intraoral impression can be considered as an alternative to a conventional impression with a consecutive digital workflow when the finish line is clearly visible and it is possible to keep it dry.

Influence of minimal extended firing on dimensional, optical, and mechanical properties of crystalized zirconia-reinforced lithium silicate glass ceramic.

This study should evaluate the influence of extended firing on the dimension, optical properties and flexural strength of a fully crystalized zirconia-reinforced lithium-silicate ceramic (ZLS) for single tooth restorations. METHODS: 150 ZLS (Celtra Duo) and 30 lithium disilicate (LDS, IPS e.max CAD) specimens (17 × 4 × 1 mm) were milled in a standard device (Cerec MC XL). The ZLS specimens were distributed equally to five experimental groups (polished, standard firing [IFU], and three extended firings). LDS acted as a control group. The extended firings of ZLS addressed the first glaze firing (EF1) as well as the subsequent glaze firing (EF2) by a controlled overheating of +15 °C during the holding time. Color was measured with a digital spectrophotometer (Shadepilot), and dimensions with a digital calliper, before and after firing. A color change of ΔE ≥1.5 and a volume change of ±0.5% was regarded as clinical relevant. All specimens underwent a three-point-bending test to calculate flexural strength and Weibull statistics. RESULTS: The color change after firing of ZLS (ΔE value; mean = 1.06; SD = 0.53) exceeded the perceptible threshold of ΔE ≥1.5 in 20% of IFU (mean = 1.18) and EF1+2 (mean = 0.95), 23% of EF1 (mean = 1.11), and 10% of EF2 (mean = 0.99) specimens with no statistical difference between the experimental groups. In 80% of IFU, 63% of EF2, 56% of EF1, and 33% of EF1+2 vol. change after firing exceeded ±0.5%. Characteristic Weibull strength σ0 and modulus m of polished ZLS specimen was affected by firing in IFU (σ0 = 314.35 MPa; m = 5.81), EF1 (σ0 = 324.68 MPa; m = 5.67), EF2 (σ0 = 326.4 MPa; m = 7.24), and EF1+2 (σ0 = 357.15 MPa, m = 3.69). LDS revealed σ0 = 405.7 MPa; m = 8.04, and polished ZLS σ0 = 219.3 MPa; m = 8.9 with statistical significant difference of the flexural strength between all fired ZLS experimental groups towards "as polished" as well as LDS. CONCLUSION: Firing of ZLS led to changes in dimensions, color, and Weibull modulus. Firing increases flexural strength, but minimal temperature extension also increases materials inhomogeneity and risk of failure. The findings call for further investigations towards firing behavior of ZLS and its clinical relevance for restorations.

Monolithic CAD/CAM laminate veneers: Reliability and failure modes.

OBJECTIVES: to evaluate the probability of survival and failure modes of lithium-disilicate, feldspathic-ceramic, and resin-nanoceramic anterior veneers cemented on dentin analog substrates after sliding-contact step-stress accelerated life testing (SSALT). METHODS: A virtual incisor tooth preparation was produced with a reduction of 1.5mm at the incisal edge and of 0.7mm buccally. A .STL file of the preparation was generated and CAD/CAM based G10 dentin-analog material was used for testing. Laminate veneers were milled in three different materials: lithium-disilicate (LDS, E.max CAD), resin-nanoceramic (RN, Lava Ultimate), and feldspathic-ceramic (FELDS, Vita Blocks). SSALT was employed where a spherical indenter contacted the veneer, slided along its interface with G10 to lift off and start a new cycle at 2Hz in water. Qualitative fractography was performed. The probability of survival (90% confidence-bounds) was calculated for several load/cycle missions. RESULTS: The probability of survival for a mission of 50,000 cycles decreased from 50 up to 150N equally for all groups and were not different between them. At 200N, the probability of survival was significantly lower for FELDS (10%) compared to RN veneers (41%), whereas LDS presented intermediate values (22%). The characteristic strength of RN (247N) was significantly higher than LDS (149N), and FELDS (151N). In FELDS and LDS, hackles, wake hackles and twist hackles indicated the direction of crack propagation. In RN, hackles were observed. CONCLUSIONS: Differences in probability of survival were observed only at 180 and 200N between groups. Failure modes were similar with veneer fracture down to the tooth-analog substrate.

Failure Rate of Direct High-Viscosity Glass-Ionomer Versus Hybrid Resin Composite Restorations in Posterior Permanent Teeth - a Systematic Review.

PURPOSE: Traditionally, resin composite restorations are claimed by reviews of the dental literature as being superior to glass-ionomer fillings in terms of restoration failures in posterior permanent teeth. The aim of this systematic review is to answer the clinical question, whether conventional high-viscosity glass-ionomer restorations, in patients with single and/or multi-surface cavities in posterior permanent teeth, have indeed a higher failure rate than direct hybrid resin composite restorations. METHODS: Eight databases were searched until December 02, 2013. Trials were assessed for bias risks, in-between datasets heterogeneity and statistical sample size power. Effects sizes were computed and statistically compared. A total of 55 citations were identified through systematic literature search. From these, 46 were excluded. No trials related to high-viscosity glass-ionomers versus resin composite restorations for direct head-to-head comparison were found. Three trials related to high-viscosity glass-ionomers versus amalgam and three trials related to resin composite versus amalgam restorations could be included for adjusted indirect comparison, only. RESULTS: The available evidence suggests no difference in the failure rates between both types of restoration beyond the play of chance, is limited by lack of head-to-head comparisons and an insufficient number of trials, as well as by high bias and in-between-dataset heterogeneity risk. The current clinical evidence needs to be regarded as too poor in order to justify superiority claims regarding the failure rates of both restoration types. Sufficiently large-sized, parallel-group, randomised control trials with high internal validity are needed, in order to justify any clinically meaningful judgment to this topic.

Implantodontia guiada no tratamento estético-reabilitador de alto desempenho: qualidade e agilidade / Guided implantology in high performance rehabilitation aesthetic treatment: quality and speed

O objetivo deste estudo foi relatar um caso clínico no qual foi utilizado o sistema KEA-TECH, para planejamento e confecção do guia tomográfi co/cirúrgico na colocação de implante cone-morse com carga imediata. Foi proposta ao paciente (sexo masculino, 69 anos), com fratura radicular do elemento 11, a utilização da coroa natural remanescente como elemento provisório imediato. Pôde-se concluir que o planejamento adequado garante sucesso na reabilitação com implantes em áreas estéticas. Além disso, a utilização do sistema KEA-TECH proporciona facilidade e rapidez nos procedimentos clínicos.

The aim of this study was to report a clinical case where the KEA-TECH system was used to plan the tomographic/surgical guide and place a morse cone implant for immediate loading. The male, 69 years-old patient presented a root fracture at tooth 11, and his natural crown was used as a provisional immediate restoration. It was demonstrated that the adequate planning guarantees the success of implant rehabilitation in esthetic areas. Besides, the use of the KEA-TECH system allows for an easier and speed procedure at the daily clinics.