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Purpose: To compare the failure rates and the prevalence of technical complications between full-coverage tooth-supported monolithic zirconia (MZ) and porcelain-veneered zirconia (PVZ) fixed dental prosthesis, based on a systematic literature review. Methods: An electronic search was performed in three databases, supplemented by hand searching. Several statistical methods were used. Results: Seventy-four publications reported 6370 restorations (4264 PVZ; 2106 MZ; 8200 abutment teeth; 3549 patients), followed up until 152 months. A total of 216 prostheses failed, and survival was statistically significant different between groups. PVZ had higher occurrence of complications than MZ; the difference was especially greater for either minor or major chipping. The difference in prevalence of either minor or major chipping was statistically significant for PVZ prostheses between cementation with glass ionomer and adhesive resin cement (higher), adhesive resin and resin-modified glass ionomer cement (RMGIC, higher), and between RMGIC (higher) and glass ionomer cement. For MZ the difference was significant only for minor chipping between RMGIC (higher) and adhesive resin cement. Abutment teeth to PVZ prostheses more often lost vitality. Decementation was not observed with RMGIC. Air abrasion did not seem to clinically decrease the decementation risk. The 5-year difference in the occurrence of minor or major chipping between MZ and PVZ prostheses was statistically significant, but nor for catastrophic fracture. Conclusion: Tooth-supported PVZ prostheses present higher failure and complication rates than MZ prosthesis. The difference in complications is striking when it comes to chipping. Clinical relevance: Awareness of the outcome differences between different types of zirconia prostheses is important for clinical practice. [ABSTRACT FROM AUTHOR]

Objectives: To examine factors influencing the primary stability of dental implants when stabilized in over-sized osteotomies using a calcium phosphate-based adhesive cement was the objective. Methods: Using implant removal torque measurements as a surrogate for primary stability, we examined the influence of implant design features (diameter, surface area, and thread design), along with cement gap size and curing time, on the resulting primary implant stability. Results: Removal torque values scaled with implant surface area and increasing implant diameters. Cement gap size did not alter the median removal torque values; however, larger gaps were associated with an increased spread of the measured values. Among the removal torque values measured, all were found to be above 32 Ncm which is an insertion torque threshold value commonly recommended for immediate loading protocols. Conclusion: The adhesive cement show potential for offering primary implant stability for different dental implant designs. In this study, the primary parameters influencing the measured removal torque values were the implant surface area and diameter. As the liquid cement prevents the use of insertion torque, considering the relationship between insertion and removal torque, removal torque can be considered a reliable surrogate for primary implant stability for bench and pre-clinical settings. Clinical relevance: At present, the primary stability of dental implants is linked to the quality of the host bone, the drill protocol, and the specific implant design. The adhesive cement might find applications in future clinical settings for enhancing primary stability of implants under circumstances where this cannot be achieved conventionally. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study is to evaluate the longevity of two fiber post cementation strategies in a prospective, multicenter, non-inferiority, double-blind randomized controlled trial. Methods: A total of 152 teeth, with adequate endodontic treatment and loss of coronal structure and bilateral simultaneous posterior occlusal contacts, were randomly allocated to receive glass fiber posts cemented with a conventional cementation strategy (CRC group: adhesive system + resin cement) (Adper Single Bond + RelyX ARC; 3 M-ESPE) or a self-adhesive cementation strategy (SRC group: self-adhesive resin cement; RelyX U100/U200; 3 M-ESPE). The patients were recalled annually for clinical and radiographical evaluation with a 93% recall rate (142 teeth, with 74 at CR groups and 68 at SRC group). The primary outcome was survival rate, considering the fiber post debonding (loss of retention). The secondary outcome included the success rate of the prosthetic treatment with crown debonding, post fracture, and tooth loss (not related to post failure). Both outcomes were evaluated annually. The Kaplan–Meier method and Cox regression with 95% confidence interval were used for the statistical analysis. Results: For the primary outcome (failures directly related to fiber posts cementation strategy), there were 4 fiber post debondings (2 per group), 8 root fractures (3 for SRC group and 5 for CRC group), and one mixed failure (debonding combined with root fracture for CRC), with both strategies presenting similar survival rates (p = 0.331), with 88.9% for the CRC group and 90.9% for the SRC group. For the secondary outcome (failures not related to fiber post cementation strategies), there were 8 crown debondings, 3 post fractures, and 3 tooth losses, with no statistically difference between groups (p = 0.701), with 77% for SRC and 82% for CRC. Conclusion: Fiber post cementation strategies with conventional or self-adhesive resin cement presents similar tooth survival and success rates. Trial registration: NCT01461239 Clinical relevance: Both adhesive cementation strategies led to high survival and success rates and are indicated for fiber post cementation, even after a long follow-up period (up to 106 months). [ABSTRACT FROM AUTHOR]

Background: Endodontically treated teeth usually can reveal an extensive loss of dental structure and require the use of intraradicular posts to provide adequate support and retention. Retention of the post depends on the surface treatment of the endodontic post itself and on the root canal dentin as well as on the type of resin-matrix cement. Purpose: The main aim of this study was to conduct an integrative review on the influence of different surface treatment methods of glass fiber-reinfored resin composite (GFRC) posts on their push-out bond strength to resin-matrix cements in endodontically treated teeth rehabiliation. Method: A literature search was performed on PubMed (via National Library of Medicine) regarding articles published within the last 10 years, using the following combination of search terms: "intracanal post" OR "endodontic post" OR "root canal post" OR "intraradicular post" OR "glass fiber" AND "resin cement" AND "adhesion" OR "bond strength" OR "shear bond strength" OR "push out". Results: Results from the selected studies recorded the highest push-out bond strength around 22.5 MPa) on GFRC posts to resin-matrix cements when the surfaces were pre-treated by grit-blasting with silicate followed by silane conditioning. However, high values of push-out bond strength (21.5 MPa) were also noticed for GFRC posts after etching with hydrogen peroxide followed by silance conditioning. Thus, the highest values of bond strength of endodontic posts to the resin-matrix cements were recorded when a combined physico-chemical approach was assessed. Non-treated surfaces showed the lowest bond strength values between 5 to and 9 MPa. Surface analyses of GFRC posts showed an increased roughness after grit-blasting or etching that promoted a mechanical interlocking of the adhesive and resin-matrix cements. Conclusion: The combined treatment of glass fiber-reinforced resin composite post surfaces by physical and chemical methods can promote the increase in roughness and chemical functionalization of the surfaces prior to cementation., That results in a high mechanical interlocking of the resin-matrix cements and a stable retention of the teeth root intracanal posts. Clinical relevance: Combining chemical and physical modification methods of surfaces can provide the most promising adhesion-enhancing pathways of GFRC posts to resin-matrix cements, that can decrease the risk of clinical failures by fracture and detachment of endodontic posts. [ABSTRACT FROM AUTHOR]

Objective: This study aims to compare the radiopacities of computer-aided design/computer-aided manufacture (CAD/CAM) blocks and the adhesive cements used for their bonding. Materials and methods: 1 ± 0.2 mm thick specimens were obtained from six different CAD/CAM blocks (Incoris TZI, IPS e.max CAD, Vita Mark II, Cerasmart, Vita Enamic, and Vita Suprinity), four different adhesive resin cements (Panavia F2.0, Variolink Esthetic DC, RelyX Unicem Aplicap, G-CEM LinkAce), and a tooth. Radiographs of the specimens from each group, a tooth section, and an aluminum (Al) step-wedge were acquired. The radiopacity values of the materials were calculated as equivalents of Al thickness using the gray level values. The data were statistically analyzed using one-way ANOVA and Tukey HSD tests. Results: All the materials except Cerasmart and Vita Enamic had significantly higher radiopacity values than dentin (p < 0.05). Of the assessed blocks, the highest radiopacity value was observed in Incoris TZI, and the lowest radiopacity value was observed in Vita Enamic. Variolink Esthetic DC and RelyX Unicem Aplicap showed significantly higher radiopacity (p < 0.05) than the other adhesive cements, including enamel and dentin. Conclusions: In this study, the majority of the CAD/CAM materials and all the adhesive resin cements were found to have sufficient radiopacity for prosthetic restorations according to the criteria set by the International Organization for Standardization (ISO). Clinical Relevance: From a clinical and biological point of view, materials should be chosen according to their radiopacity and other properties, such as biocompatibility and esthetics. If the selected restorative CAD/CAM blocks have a radiopacity value less than or equal to dentin, cements with higher radiopacity values are recommended to facilitate radiological diagnoses for periphery and interface of restorations. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to evaluate the shear bond strength inherent to immediate and delayed definitive composite resin restorations, over three different biomaterials. Methods: Fifty-four aluminum blocks were randomly assigned to six experimental groups (n = 9) according to the biomaterial (Biodentine, TotalFill BC Putty, or PCM) and restoration timing (immediate or 7 days delayed). Regarding the restorative procedures, a two-step self-etch bonding system (Clearfil SE Bond) was applied and subsequently restored using a flowable composite resin (SDR). After shear bond strength testing, fracture pattern analysis was performed. The significance level was set at α = 0.05. Results: Within the immediate groups, Biodentine showed the highest mean shear bond strength value, with no statistically significant differences (P > 0.05) being detected when compared with both TotalFill (P = 0.072) and PCM (P = 0.232) groups. Regarding the delayed restoration groups, Biodentine and TotalFill presented the highest mean shear bond strength value, with statistical differences when compared with PCM (P = 0.002 and P = 0.043, respectively). No statistically significant differences (P > 0.05) were verified between both immediate and delayed groups for each tested biomaterial. Also, a statistically significant association was found between the fracture type and the biomaterial (P < 0.001). Conclusions and clinical relevance: Our findings suggest that all tested biomaterials present suitable alternatives which allow to perform restorative procedures immediately after pulp capping biomaterial placement (3 or 12 min, depending on the bioactive cement), therefore requiring one single appointment to complete the procedure. Biodentine and TotalFill BC Putty have shown superior shear bond strength results when compared with PCM, within a delayed timeframe (7 days). [ABSTRACT FROM AUTHOR]

Objectives: To perform a review on the influence of preheating and/or heating of resinous and ionomeric materials on their physical and mechanical properties and to discuss the benefits and methods of preheating/heating that have been used. Material and methods: A search was performed in the Pubmed, Scopus, Scielo, and gray literature databases. In vitro studies published from 1980 until now were searched using the descriptors "composite resins OR glass ionomer cements OR resin cements OR adhesives AND heating OR preheating." Data extraction and quality of work evaluation were performed by two independent evaluators. Results: At the end of reading the search titles and abstracts, 74 articles were selected. Preheating of composite resins reduces viscosity, facilitates adaptation to cavity preparation walls, increases the degree of conversion, and decreases the polymerization shrinkage. Preheating of resin cements improves strength, adhesion, and degree of conversion. Dental adhesives showed good results such as higher bond strength to dentin. However, unlike resinous materials, ionomeric materials have an increase in viscosity upon heating. Conclusions: Preheating improves the mechanical and physical properties. However, there is a lack of clinical studies to confirm the advantages of preheating technique. Clinical relevance: Preheating of dental restorative materials is a simple, safe, and successful technique. In order to achieve good results, agility and training are necessary so the material would not lose heat until the restorative procedure. Also, care is necessary to avoid bubbles and formation of gaps, which compromises the best restoration performance. [ABSTRACT FROM AUTHOR]

Objective: This study evaluated the influence of endodontic sealers with different chemical compositions on bond strength of resin cement/glass fiber post junction to root dentin. Materials and methods: Seventy-two maxillary canines roots were instrumented with Reciproc (#R50) and distributed in 6 groups (n = 12) according to endodontic sealers: G1—control (no sealer); G2—Endofill; G3—Sealapex; G4—AH Plus; G5—Sealer Plus; G6—EndoSequence BC. The glass fiber post was cemented with Panavia F in 10 of the specimens. Two specimens from each group did not receive post and were analyzed by SEM to verify presence of filling material. Three slices were obtained from each third. The first slice was subjected to push-out test and type of failure. The second slice was imaged using laser confocal microscopy for evaluation of dentin/resin cement adhesive interface. Bond strength (BS) data were analyzed using two-way ANOVA and Tukey's post hoc tests; for LCM data, we used Kruskal-Wallis and Dunn's tests. Results: Endofill yielded the lowest BS values (p < 0.05). The control and AH Plus groups differed from all others (p < 0.05). In all groups, adhesive to dentin failure predominated. Most specimens of control and AH Plus groups had acceptable interfaces, while those of EndoSequence BC, Sealapex, and Sealer Plus groups ranged between acceptable and poor interfaces. Overall, few filling material remnants were observed on the dentin. Conclusion: EndoSequence BC, Sealapex, Sealer Plus, and Endofill negatively interfere with BS of glass fiber post/resin cement junction to root dentin. Clinical relevance: In cases whose restoration planning includes a post cemented with resin cement, it is recommended that endodontic sealer be based on epoxy resin. [ABSTRACT FROM AUTHOR]

Objectives: This in vitro study aimed to predict the potential of fracture initiation after long-term incubation (LTI) of lithium-disilicate restorations due to a hygroscopic expansion of self-adhesive resin cement (SARC) used as core build-up material. Methods: Human maxillary central incisors were divided into four groups ( n = 10). Teeth were endodontically treated and decoronated. Specimens were restored in a one-stage post-and-core procedure using experimental dual-curing SARC. Three application protocols to build up the core were compared as follows: I, auto-polymerisation; II, dual curing including 40 s light-initiated polymerisation; and III, an open matrix technique in a dual-curing mode. In group IV, a chemical-curing composite core build-up material served as control. For all specimens, a 2-mm ferrule design was ensured. Full anatomic lithium-disilicate crowns were adhesively luted. One-year LTI in 0.5 % chloramine solution at 37 °C was performed. Restorations were examined after 3, 6, 9 and 12 month of storage. Survival rates were calculated using log-rank statistics ( p = 0.05). Results: Fifty per cent of lithium-disilicate crowns of groups I and II showed visible crack propagation after 9 months of incubation, while one crown failed in group III. No failure was observed in group IV. The survival rates differed significantly ( p = 0.017). Conclusion: SARC used to build up the core of severely damaged endodontically treated teeth does have the potential to cause fracture of lithium-disilicate crown restorations. Clinical relevance: Hygroscopic expansion of self-adhesive resin cements used as a core build-up material might have an adverse impact on longevity of glass-ceramic crowns. [ABSTRACT FROM AUTHOR]

Objectives: Marginal discoloration of luting cement may affect the appearance of esthetic restorations. This study evaluated the color stability of current adhesive resin cements after immersion in coffee. Materials and methods: Four dual-cured resin cements (Clearfil SA cement Automix Universal, Maxcem Elite Clear, Maxcem Elite Yellow, and RelyX Unicem2 Automix A2) and two chemical-cured resin cements (Super-Bond C&B Clear and Super-Bond C&B Esthetic) were examined. The CIE L* a* b* of 2.0-mm-thick disc-shaped specimens was measured using a spectrophotometer on a white background ( n = 6). The color differences (∆ E) after 1-day and 1-week immersion in 37 °C water or coffee were analyzed by two-way ANOVA by selecting immersion solution and product as main factors, followed by Tukey's HSD test (α = 0.05). Water sorption and solubility were also evaluated. Results: The two-way ANOVA of the ∆ Es suggested that the two main factors and their interaction were significant. The ∆ Es after coffee immersion were significantly greater than those after water immersion, except for Super-Bond C&B Esthetic. The ∆ Es after water immersion were not significantly different among the products; those of Maxcem Elite Clear and Maxcem Elite Yellow after coffee immersion were significantly greater than the others. The water sorption and solubility significantly correlated with the ∆ Es. Conclusions: The ∆ Es of the adhesive resin cements examined after 1-week coffee immersion were significantly different among the products. The product showing greater water sorption and solubility displayed greater color change. Clinical relevance: Adhesive resin cements should be carefully selected when the marginal appearance of the ceramic restoration is important. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the push-out strength of glass fiber posts dependent on the resin cement. One hundred human teeth were divided into five groups ( n = 20). Two glass fiber post systems (DT Light SL (DTSL) and RelyX Fiber Post (RF)) were used. DTSL posts were cemented with one 'etch & rinse' system (ER) or one of three self-adhesive resin cements (SA). The RF posts were cemented with RelyX Unicem. Afterwards, half of the specimens were thermocycled (TC; 5°C/55°C, 5,000 cycles). All specimens were cut into disks (thickness, 2 mm). The push-out test was performed (crosshead speed, 1 mm/min), fracture types were determined (×25 and ×40 magnification), and statistical analysis was performed (one-way analysis of variance (ANOVA), Scheffe test, p < 0.05). One-way ANOVA showed a significant influence of the resin cement on the push-out strength of the glass fiber posts before thermocycling ( p < 0.001). After TC, no significant differences were detected. Microscopic evaluation showed mainly adhesive failures between post and cement for ER or mixed fractures for SA. The bond strength of adhesively cemented glass fiber posts is not dependent on the type of resin cement after TC. The use of SA can lead to bond strength values comparable to ER. Self-adhesive resin cements could be used just as well as resin cements with 'etch & rinse' adhesive systems for the cementation of glass fiber posts. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the push-out bond strengths of self-adhesive resin cements to epoxy resin-based fiber posts after challenging by thermocycling. Thirty-six single-rooted premolars were endodontically treated, and the post-spaces were drilled to receive RelyX Fiber posts #1. Three self-adhesive resin cements (RelyX Unicem, G-Cem, and Breeze) were used for luting fiber posts. The bonded specimens were either stored for 1 month in a moist field (37°C) or submitted to thermocycling (5,000 times) prior to push-out test. The maximum force required to dislodge the post via an apical-coronal direction was recorded (megapascal). The data were statistically analyzed with two-way ANOVA and Tukey tests ( p < 0.05). The factors 'luting cement' and 'thermocycling' significantly influenced bond strengths. The initial push-out values of RelyX Unicem and Breeze were higher than those of G-Cem. After thermocycling, the bond strength of G-Cem increased and no differences were found between groups. RelyX Unicem and Breeze bond strengths were not affected by the thermal challenge. Thermal cycling and cement type differently influence the bond strengths of self-adhesive resin cements. Self-adhesive cements can represent an option for luting fiber posts into root canal [ABSTRACT FROM AUTHOR]

This study tested the impact of Gluma Desensitizer on the tensile strength of zirconia crowns bonded to dentin. Human teeth were prepared and randomly divided into six groups ( N = 144, n = 24 per group). For each tooth, a zirconia crown was manufactured. The zirconia crowns were cemented with: (1) Panavia21 (PAN), (2) Panavia21 combined with Gluma Desensitizer (PAN-G), (3) RelyX Unicem (RXU), (4) RelyX Unicem combined with Gluma Desensitizer (RXU-G), (5) G-Cem (GCM) and (6) G-Cem combined with Gluma Desensitizer (GCM-G). The initial tensile strength was measured in half ( n = 12) of each group and the other half ( n = 12) subjected to a chewing machine (1.2 Mio, 49 N, 5°C/50°C). The cemented crowns were pulled in a Universal Testing Machine (1 mm/min, Zwick Z010) until failure occurred and tensile strength was calculated. Data were analyzed with one-way and two-way ANOVA followed by a post hoc Scheffé test, t test and Kaplan-Meier analysis with a Breslow-Gehan analysis test ( α = 0.05). After the chewing simulation, the self-adhesive resin cements combined with Gluma Desensitizer showed significantly higher tensile strength (RXU-G, 12.8 ± 4.3 MPa; GCM-G, 13.4 ± 6.2 MPa) than PAN (7.3 ± 1.7 MPa) and PAN-G (0.9 ± 0.6). Within the groups, PAN, PAN-G and RXU resulted in significantly lower values when compared to the initial tensile strength; the values of all other test groups were stable. In this study, self-adhesive resin cements combined with Gluma Desensitizer reached better long-term stability compared to PAN and PAN-G after chewing simulation. [ABSTRACT FROM AUTHOR]