Clinical longevity of extensive direct resin composite restorations after amalgam replacement with a mean follow-up of 15 years

Objectives: The aim of this retrospective clinical study was to determine the survival of extensive direct resin composite restorations after amalgam replacement on vital molars and premolars after a mean observation period of 15 years.Methods: Between January 2007 and September 2013, a total of 117 extensive cusp replacing direct resin composite restorations were placed in 88 patients in a general dental practice. These were indicated for replacement of existing amalgam restorations. Tooth vitality, the absence of at least one cusp in premolars, and at least two cusps in molars were considered for inclusion. The long-term follow-up of the restorations, re-evaluated after up to 17 years using the original evaluation criteria is reported.Results: 81 of 88 patients (92.1%) and 106 of 117 restorations (90.6%) were available for follow-up. The cumulative success rate was 62.0% (95% CI: 47.3–76.2, AFR 2.79%) after a mean observation time of 163.4 months, the cumulative survival rate was 74.7% (95% CI: 59.8–89.6%, AFR: 1.70%) after a mean observation time of 179.1 months. The number of cusps replaced in premolars had a statistically significant influence on the success and survival rate of the restorations (HR of respectively, 2.974 and 3.175, p = &lt;0.0005). Premolars with two cusps replaced had 297% more chance of failure than premolars with one cusp replaced.Conclusions: Extensive direct resin composite restorations placed after amalgam replacement showed good survival after a mean observation period of 15 years. The number of cusps involved had a statistically significant influence on the longevity of the restorations in premolars.Clinical Significance: With good survival and low annual failure rates, direct resin composite restorations are a suitable treatment for repairing extensive defects in posterior teeth involving multiple cusps and surfaces, provided that they are placed by a dentist who has long experience and is skilled in the placement of direct composite materials.</p

8-year multicenter retrospective study on partial laminate veneers

Purpose: This retrospective study aimed to evaluate the survival and success rates of ceramic partial laminate veneers. Scanning electron microscopy was used to evaluate fractures and marginal defects. Methods: In total, 31 patients received 79 partial laminate veneers on the maxillary anterior teeth. After adhesive luting, restorations were evaluated by calibrated clinicians for up to eight years using modified United States Public Health Service (USPHS) criteria. In addition, epoxy resin replicas were fabricated from silicone impressions and analyzed using scanning electron microscopy. Survival analyses were performed using the Kaplan-Meier and log-rank tests (α = 0.05). Success was analyzed in percentages by comparing the baseline and last follow-up. Results: The cumulative survival rates were 100% after 1 year; 95.9% (SE 2.8%) after 5 years; and 61.4% (SE 25.3%) after 8 years. No significant differences (P &gt; 0.05) were observed between functional and non-functional restorations. Changes in the USPHS criteria evaluation were only observed for adaptation: 12.5% (SE 4.7%), marginal discoloration: 4.2% (SE 3.0%), color match: 4.2% (SE 3.0%), and fractures: 16.7% (SE 5.3%). Scanning electron microscopy evaluations revealed undetected initial cracks and deficiencies in the restorations. Conclusions: Partial laminate veneers displayed good survival rates during the long-term follow-up. The main problems observed were related to the quality of the margins, color mismatch, and restoration integrity. However, in most cases, restoration replacement was not required.</p

Deep margin elevation:A case report study

Deep subgingival margins are a much-debated topic in adhesive and restorative dentistry. The hydrophobic trait of direct composite resin materials challenges the restorative procedure of cavities with deep subgingival margins since isolation is complicated. A correct indication for a deep margin elevation (DME) treatment is the key to its clinical success, and adequate adaptation of the DME is crucial to its clinical performance. An adequate adaptation of the DME may potentially reduce bacterial accumulation and reduce the incidence of secondary caries as well as maintain periodontal health. The present case report aims to provide a step-by-step overview of the DME technique when applied in combination with a partial indirect glass-ceramic restoration and also provides clinical guidelines to tackle deep subgingival cavities. The indication for a DME and the selection of appropriate materials are explained, supported by the literature.</p

Shear bond strength of two composite resin cements to multiphase composite resin after different surface treatments and two glass-ceramics

AIM: To compare the shear bond strength (SBS) after aging of two dual-curing composite resin cements to multiphase composite resin (experiment) and glass-ceramics (control). METHODS: Seventy computer-aided design/computer-aided manufacturing (CAD/CAM) blocks were prepared: 24 multiphase composite resin blocks (Lava Ultimate; experiment), and 12 control blocks (groups 5 and 6: 6 IPS e.max CAD, 6 IPS Empress CAD). Surface treatments of the experiment groups were: 1) Al2O3 airborne particle abrasion; 2) bur-roughening; 3) silica-coated aluminum oxide particle abrasion; and 4) hydrofluoric (HF) acid etching. Per study group, Variolink II (a) and RelyX Ultimate (b) were used as cements. Per treatment group, four cement cylinders were adhered to the conditioned blocks (n = 12). After thermocyclic aging (10.000x, 5°C to 55°C), notch-edge shear testing was applied. Modes of failure were examined. A P value of 0.05 was considered significant. RESULTS: Groups 1a (18.68 ± 3.81) and 3a (17.09 ± 3.40) performed equally to 6a (20.61 ± 4.10). Group 5a (14.39 ± 2.80) did not significantly differ from groups 1a, 3a, and 4a (15.21 ± 4.29). Group 2a (11.61 ± 3.39) showed the lowest bond strength. For the RelyX Ultimate specimens, mean bond strengths were: 1b (18.12 ± 2.84) > 4b (15.57 ± 2.31) > 2b (12.34 ± 1.72) = 3b (11.54 ± 2.45) = 6b (12.31 ± 1.87) > 5b (0.78 ± 0.89). Failure mode analysis showed a significant association between bond strength values and modes of failure (chi-square). CONCLUSION: The SBS of the composite cements to the multiphase composite resin that was treated by Al2O3 or silica-coated aluminum oxide particle abrasion is comparable to the bond of the control groups

Shear bond strength of two composite resin cements to multiphase composite resin after different surface treatments and two glass-ceramics

AIM: To compare the shear bond strength (SBS) after aging of two dual-curing composite resin cements to multiphase composite resin (experiment) and glass-ceramics (control). METHODS: Seventy computer-aided design/computer-aided manufacturing (CAD/CAM) blocks were prepared: 24 multiphase composite resin blocks (Lava Ultimate; experiment), and 12 control blocks (groups 5 and 6: 6 IPS e.max CAD, 6 IPS Empress CAD). Surface treatments of the experiment groups were: 1) Al2O3 airborne particle abrasion; 2) bur-roughening; 3) silica-coated aluminum oxide particle abrasion; and 4) hydrofluoric (HF) acid etching. Per study group, Variolink II (a) and RelyX Ultimate (b) were used as cements. Per treatment group, four cement cylinders were adhered to the conditioned blocks (n = 12). After thermocyclic aging (10.000x, 5°C to 55°C), notch-edge shear testing was applied. Modes of failure were examined. A P value of 0.05 was considered significant. RESULTS: Groups 1a (18.68 ± 3.81) and 3a (17.09 ± 3.40) performed equally to 6a (20.61 ± 4.10). Group 5a (14.39 ± 2.80) did not significantly differ from groups 1a, 3a, and 4a (15.21 ± 4.29). Group 2a (11.61 ± 3.39) showed the lowest bond strength. For the RelyX Ultimate specimens, mean bond strengths were: 1b (18.12 ± 2.84) > 4b (15.57 ± 2.31) > 2b (12.34 ± 1.72) = 3b (11.54 ± 2.45) = 6b (12.31 ± 1.87) > 5b (0.78 ± 0.89). Failure mode analysis showed a significant association between bond strength values and modes of failure (chi-square). CONCLUSION: The SBS of the composite cements to the multiphase composite resin that was treated by Al2O3 or silica-coated aluminum oxide particle abrasion is comparable to the bond of the control groups

Shear bond strength of two composite resin cements to multiphase composite resin after different surface treatments and two glass-ceramics

AIM: To compare the shear bond strength (SBS) after aging of two dual-curing composite resin cements to multiphase composite resin (experiment) and glass-ceramics (control). METHODS: Seventy computer-aided design/computer-aided manufacturing (CAD/CAM) blocks were prepared: 24 multiphase composite resin blocks (Lava Ultimate; experiment), and 12 control blocks (groups 5 and 6: 6 IPS e.max CAD, 6 IPS Empress CAD). Surface treatments of the experiment groups were: 1) Al2O3 airborne particle abrasion; 2) bur-roughening; 3) silica-coated aluminum oxide particle abrasion; and 4) hydrofluoric (HF) acid etching. Per study group, Variolink II (a) and RelyX Ultimate (b) were used as cements. Per treatment group, four cement cylinders were adhered to the conditioned blocks (n = 12). After thermocyclic aging (10.000x, 5°C to 55°C), notch-edge shear testing was applied. Modes of failure were examined. A P value of 0.05 was considered significant. RESULTS: Groups 1a (18.68 ± 3.81) and 3a (17.09 ± 3.40) performed equally to 6a (20.61 ± 4.10). Group 5a (14.39 ± 2.80) did not significantly differ from groups 1a, 3a, and 4a (15.21 ± 4.29). Group 2a (11.61 ± 3.39) showed the lowest bond strength. For the RelyX Ultimate specimens, mean bond strengths were: 1b (18.12 ± 2.84) > 4b (15.57 ± 2.31) > 2b (12.34 ± 1.72) = 3b (11.54 ± 2.45) = 6b (12.31 ± 1.87) > 5b (0.78 ± 0.89). Failure mode analysis showed a significant association between bond strength values and modes of failure (chi-square). CONCLUSION: The SBS of the composite cements to the multiphase composite resin that was treated by Al2O3 or silica-coated aluminum oxide particle abrasion is comparable to the bond of the control groups