Effect of surface treatment and aging on bond strength of composite resin onlays.

STATEMENT OF PROBLEM: Additional polymerization of indirect composite resins enhances their physical properties but lessens the potential for chemical bonding. PURPOSE: The purpose of this in vitro study was to evaluate the influence of different surface treatments and 6-month water storage on the microtensile bond strength (µTBS) of composite resin onlays. MATERIAL AND METHODS: Composite resin onlays (Filtek Z250) randomly received 6 different surface treatments: (1) airborne-particle abrasion with 27-µm alumina particles+Adper Scotchbond 1XT adhesive application, (2) airborne-particle abrasion with alumina particles+silane application (ESPE SIL)+Adper Scotchbond 1XT, (3) airborne-particle abrasion with alumina particles+Scotchbond Universal adhesive, (4) tribochemical silica coating with 30-µm particles (CoJet Sand)+Adper Scotchbond 1XT adhesive, (5) tribochemical silica coating+silane application+Adper Scotchbond 1XT, and (6) tribochemical silica coating+Scotchbond Universal adhesive. Onlays were luted to fresh composite resin specimens with RelyX Ultimate resin cement. Bonded assemblies were stored in water for 24 hours or 6 months at 37°C and subjected to the µTBS test. Additional surface-treated composite resin onlays were analyzed with a contact profilometer to determine average roughness, and micromorphologic changes were analyzed with scanning electron microscopy. RESULTS: Airborne-particle abrasion with alumina followed by Adper Scotchbond 1XT or Scotchbond Universal adhesive application provided the highest bond strength values at 24 hours. Lower values were obtained after tribochemical silica coating. After 6 months of artificial aging, airborne-particle abrasion with alumina or silica-coated alumina particles followed by Scotchbond Universal application yielded the greatest bond strength results. Airborne-particle abrasion with alumina produced the highest roughness values and a more irregular surface. CONCLUSION: Adhesive selection seems to be relevant to the µTBS of luted composite resin onlays after 6 months of water aging, as specimens treated with Scotchbond Universal, after alumina airborne-particle abrasion or tribochemical silica coating, yielded the highest values and better aging stability.

Clinical Performance of Indirect Composite Onlays as Esthetic Alternative to Stainless Steel Crowns for Rehabilitation of a Large Carious Primary Molar.

OBJECTIVE: The aim of the present study was to evaluate the clinical performance of indirect resin composite onlays (IRC onlay) compared to stainless steel crowns (SSCs), as an esthetic alternative for rehabilitation of extensively carious primary molars. STUDY DESIGN: Fifty pediatric patients each received either IRC onlay or SSC randomly on extensively carious endodontically treated primary molars. All the restorations were evaluated at baseline and then every 6 months till 36 months using 'modified FDI criteria' for retention, marginal integrity, occlusion, proximal contact, secondary caries and gingival health. The dental chair side treatment time and post-operative acceptability were also evaluated for both the groups. RESULTS: The cumulative survival rate of IRC onlays was 82.9% compared to 90.7% for SSCs over a time period of 36 months. The difference between the two study groups at various time intervals in terms of retention, marginal integrity, secondary caries, proximal contact, occlusion and gingival health was not statistically significant (p>0.05). The IRC onlays required significantly less mean chair side treatment time and were preferred the most by parents and children as per VAS scores compared to SSCs. CONCLUSION: IRC onlays are an acceptable esthetic alternative to SSCs and may be considered for use in aesthetically conscious children/parents as per their preference.

Analysis of an administrative database of indirect restorations over 11 years.

AIM: This paper describes the database used to assess the survival of indirect restorations and presents general data on survival of these restorations. METHODS: Data, based on the complete attendance and treatment history, over the 11 years from 1991 to 2001, of a statistically representative sample of 23,165 General Dental Services' (GDS) patients in England and Wales, all of whom received at least one indirect restoration during the observation period, have been analysed. The patients on the database received a total of 36,397 courses of treatment, and there were 52,481 indirect restorations placed. The method of analysis involved the estimation of the probability that the patient will eventually return, given an interval without attending, by analysing the observed patterns of re-attendance. This estimated probability of re-attendance was then used to modify the standard Kaplan-Meier procedure to produce realistic estimates of the hazard of re-intervention. RESULTS: Overall, 75% of indirect restorations remained without re-intervention after 5 years, and 61% after 10. Crowns outperformed other types of indirect restoration. Multi-surface metal inlays, by contrast, had a median interval to re-intervention of less than 8 years. CONCLUSIONS: The times to re-intervention for different types of indirect restoration have been successfully estimated and crowns shown to outperform veneers and inlays.

Dentist-time expenditure for two different adhesive all-ceramic systems.

OBJECTIVES: The purpose of this clinical investigation was to compare a chair-side adhesive all-ceramic system to a laboratory processed adhesive all-ceramic system with respect to quality and time expenditure for the dentist. METHODS: The same dentist treated 10 patients, who were each to receive two large posterior single tooth restorations of similar location and extent. One restoration was made in the laboratory by using the IPS Empress system [LAB], the other one was done chair-side by utilizing the Cerec system [CHAIR]. The time expenditure was measured for [LAB] and [CHAIR] and compared by the Wilcoxon signed rank test. The restorations were also evaluated according to the USPHS criteria. RESULTS: The mean time expenditure for the dentist with low-level assistance was 111:03 min [S.D.+/-24:09 min] for [LAB] and 115:31 min [S.D.+/-15:54 min] for [CHAIR]. Time expenditure with medium level assistance for the operator was 100:53 min [S.D.+/-23:59] for [LAB] and 105:50 [S.D.+/-15:28] for [CHAIR]. Assuming a high level of assistance, the mean time values were 53:11 min [S.D.+/-14:29] for [LAB] and 54:29 min [S.D.+/-09:21] for [CHAIR]. The baseline investigation according to the modified USPHS criteria did not reveal any differences between [CHAIR] and [LAB]. CONCLUSION: There were no statistical significant differences with respect to time expenditure or quality between [LAB] and [CHAIR] in this study.

[Clinical evaluation of a quality criteria system for ceramic inlay restorations]. / Minoségi követelményrendszer alkalmazása kerámia-restaurációk ellenorzo vizsgálatában.

The aim of this study was to test the utilization of a generally accepted quality criteria system (United States Public Health Services Modified Quality Criteria) in the authors' practice, in the cases of all ceramic inlays and onlays. 41 ceramic inlays/onlays--29 pressed and 12 laminated--were made for 28 patients. Restorations were controlled after 2 years of cementation. According to the USPHS criteria system the following characteristics were controlled: anatomic contour, marginal integrity, marginal discoloration, color match, secondary caries, and surface roughness. In addition, postoperative sensitivity, patient's satisfaction and tooth vitality were examined as well. The USPHS quality criteria system together with the complementary data proved to be an objective examination method that was easily applicable to our clinical practice. On the basis of these studies the utilization of this system together with patient's satisfaction, tooth vitality and sensitivity records appeared a good basis for a regular quality control system of ceramic inlays and onlays.

Survival Rate of Resin and Ceramic Inlays, Onlays, and Overlays: A Systematic Review and Meta-analysis.

This systematic review and meta-analysis aimed to evaluate the survival rate of ceramic and resin inlays, onlays, and overlays and to identify the complication types associated with the main clinical outcomes. Two reviewers searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials for articles published between 1983 through April 2015, conforming to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews. Clinical studies meeting the following criteria were included: 1) studies related to resin and ceramic inlays, onlays, and overlays; 2) prospective, retrospective, or randomized controlled trials conducted in humans; 3) studies with a dropout rate of less than 30%; and 4) studies with a follow-up longer than 5 y. Of 1,389 articles, 14 met the inclusion criteria. The meta-regression indicated that the type of ceramic material (feldspathic porcelain vs. glass-ceramic), study design (retrospective vs. prospective), follow-up time (5 vs. 10 y), and study setting (university vs. private clinic) did not affect the survival rate. Estimated survival rates for glass-ceramics and feldspathic porcelain were between 92% and 95% at 5 y (n = 5,811 restorations) and were 91% at 10 y (n = 2,154 restorations). Failures were related to fractures/chipping (4%), followed by endodontic complications (3%), secondary caries (1%), debonding (1%), and severe marginal staining (0%). Odds ratios (95% confidence intervals) were 0.19 (0.04 to 0.96) and 0.54 (0.17 to 1.69) for pulp vitality and type of tooth involved (premolars vs. molars), respectively. Ceramic inlays, onlays, and overlays showed high survival rates at 5 y and 10 y, and fractures were the most frequent cause of failure.

Marginal adaptation of different types of all-ceramic partial coverage restorations after exposure to an artificial mouth.

OBJECTIVES: To determine the influence of the preparation design and the dimensions of all-ceramic partial coverage restorations (PCR) on the marginal accuracy before and after masticatory simulation. METHODS: In this in vitro study 80 extracted human maxillary molars were restored with MOD inlay restorations and four different modified PCR restorations using a new press ceramic IPS e.max Press (IPS e.max Press VP 1989). The teeth were divided into five groups of 16 specimens each and prepared as follows: Group A received an MOD inlay preparation and Group B, C, D and E received modified PCR. The restorations were adhesively luted and exposed to a mastication simulator. The discrepancies of the marginal fit were examined on epoxy replicas before and after luting as well as after masticatory simulation at 200x magnification. RESULTS: The mean (geometrical) [95% confidence limits] marginal gap decreased from Group A to E before cementation (A-83[77-90]microm, B-68[65-70]microm, C-59[55-64]microm, D-56[52-61]microm, E-50[45-55]microm). Group A had significantly higher marginal gap values than group B (p = 0.017) and the other groups (p<0.0001). After cementation the marginal accuracy was recorded as following: A-103[93-114]microm, B-101[94-108]microm, C-93[89-98]microm, D-102[98-105]microm and E-99[96-102]microm. Cementation increased the marginal gap in groups B-E significantly (p<0.00001), not significantly in group A (p = 0.059). Artificial ageing (A-116[106-127]microm, B-114[109-120]microm, C-106[103-110]microm, D-109[100-118]microm and E-109[105-112]microm) led to further significant decrease of marginal accuracy in Group B (p = 0.029) and C (p = 0.026) only. After cementation and masticatory simulation of the ceramic restorations, the marginal gap values of Groups A, B, C, D and E did not significantly differ from each other (p = 1.00). CONCLUSIONS: The result of this in vitro study showed that IPS e.max Press can be used to fabricate all-ceramic inlays and PCR which meet the requirements in terms of a clinically acceptable marginal gap, irrespective of the preparation design used. However, the preparation design and dimensions of the restorations appeared to affect the initial marginal fit and flowing off of luting material during the cementation process. The factors responsible for these findings require further substantiation.

The quality of impressions for crowns and bridges received at commercial dental laboratories.

OBJECTIVE: To determine the quality of impressions for crown and bridge work made in general dental practice. DESIGN AND SETTING: All impressions for crown and bridge work which had been sent to four commercial dental laboratories in the UK were assessed by two examiners, each laboratory being visited on two occasions. MATERIALS AND METHODS: 290 cases which had been received by the laboratories on the days of the visits were assessed for a number of factors related to quality. There was no selection or rejection--all impressions received were examined. RESULTS: Flexible plastic trays were used for the majority of working impressions for crown and bridge work in general dental practice (72%), many had been re-used (> 13%), defects in the recording of the prepared teeth were common, and cross infection control was not routine. CONCLUSIONS: Quality standards for impressions for crown and bridge work in general dental practice in the UK are a cause for concern if the sample of cases seen in this study is typical.

The clinical performance of ceramic inlays: a review.

The availability of improved ceramic materials, bonding techniques, new technology and issues of amalgam safety have led to a revival of interest in ceramic inlays in dentistry over the past ten years. Clinical studies have been carried out during this time using various evaluation techniques to assess the clinical performance of these restorations. In this paper, recent clinical studies are examined and a review of the current state of knowledge regarding the clinical performance and survival statistics of ceramic inlays is presented. The major problems associated with ceramic inlay therapy appear to be fracture, hypersensitivity, degree of fit, maintenance of marginal integrity, microleakage, bond failures and cement wear. Other areas which also affect the clinical performance of ceramic inlays are ceramic wear, opposing tooth wear, plaque accumulation, gingivitis, secondary caries, colour stability, anatomic form and radiopacity. Recommendations based on the findings of clinical studies are also presented and whilst no specific material or technique has been shown to be clearly superior, certain principles which predispose to success can be identified. When compared with other forms of aesthetic intracoronal restorations, ceramic inlays perform well. However, their high cost and extreme technique sensitivity would appear to restrict their use to certain limited clinical situations.

[Grinding precision and accuracy of the fit of Cerec-2 CAD/CIM inlays]. / Schleifpräzision und Passgenauigkeit von Cerec-2-CAD/CIM-Inlays.

The grinding precision of one Cerec-1 (C1) and one Cerec-2 (C2) CAD/CIM unit each was evaluated using standardized inlay-like (mod) samples (n = 40) of Vita Cerec Mk II porcelain and Dicor MGC glass ceramic. Typical dimensions (B, E, F, H) of the sampleS were measured and the standard deviations (SD) analysed statistically using the F-test. SD of C2-machined sample dimensions were significantly lower using both Vita, B: p < 0.05; E: p < 0.001; F: p < 0.001; H: p < 0.001, and Dicor MGC, B: p < 0.05; E: p < 0.001; F: p < 0.001; H: p < 0.01, than those machined with C1, indicating a strong improvement of grinding precision of C2 compared to C1. Accuracy of fit to human molar cavities of mod inlays machined with C1 (n = 6) and C2 (n = 6) was evaluated using a scanning electron microscope with 100x magnification. The width of the interfacial luting gap was generally lower in C2 inlays (56 +/- 27 microns) than with C1 (84 +/- 38 microns). Significant differences (t-test) were seen in margin sections "cervical line angles above CEJ" (C1 = 124 +/- 44/C2 = 59 +/- 30 microns, p < 0.05), "cervical line angles at CEJ" (C1 = 109 +/- 55/C2 = 67 +/- 27 microns, p < 0.05) and "gingival margin above CEJ" (C1 = 81 +/- 32 microns/C2 = 31 +/- 18 microns, p < 0.05).

Indirect posterior composite inlays and onlays.

Indirect posterior composite inlays and onlays are a valuable part of the cosmetic dentist's repertoire of services. They fulfill most of the requirements for an esthetic alternative to the previously considered amalgam, gold, porcelain, and directly placed composite restorations. As in all other cosmetic dental procedures, attention to detail is essential for success. Improving technology will continue to have an impact on the place these restorations occupy in future cosmetic practice.

[Porcelain onlays]. / Porseleinen onlays.

This article covers the clinical application of feldspathic porcelain onlays. The indication, tooth preparation, try-in and cementation procedures using total etching and the latest concepts in dentin bonding are discussed. When properly executed fired porcelain onlays can meet the highest esthetic demands but they require maximum skills, both of the dental surgeon and of the dental technician.

[Composite inlays]. / Composietinlays.

Composite restorations shrink most during curing. In large cavities more shrinkage may be expected. The composite inlay is especially developed to overcome these disadvantages. After curing of the composite inlay causes secondary polymerization increasing several material properties such as wear resistance and stress relaxation. Clinical results are reviewed and the benefits of the composite inlay technique discussed.

In search of a gold standard.

This is a review article of relevant research to offer best-practice advice to the practitioner regarding the choice of intracoronal indirect restorative materials. The paper reviews the use of cast gold, a variety of porcelain materials and indirect composite resin materials as inlay materials. Subjects reviewed are the effects on tooth strength, the effect of bonding the material on tooth strength, stress analysis on teeth using different restorative material choice of luting material, wear of the material and its antagonist surface and clinical research outcomes and conclusions.

[Ceramic inlays and onlays]. / Keramische inlays en onlays.

Large direct composite restorations can induce shrinkage related postoperative sensitivity. Indirect resin-bonded (tooth colored) restorations may perhaps prevent these complaints. Indirect bonded ceramics are especially attractive because of their biocompatibility and esthetic performance. Several procedures and techniques are currently available for the fabrication of ceramic restorations: firing, casting, heat-pressing and milling. In this article the different systems are described. Advantages, disadvantages and clinical performance of ceramic inlays are compared and discussed.

[In vivo and in vitro study of the marginal sealing in ceramic-covered gold inlays]. / A kerámialeplezésü aranyinlayk széli záródásának in vivo és in vitro vizsgálata.

In the view of the patients, Galvano-Inlays fulfil esthetic requirements in contrast to cast restaurations. However, it was decided to evaluate the fine gold margins. The marginal seal of Galvano-Inlays in different stages of production was evaluated by means of light microscopy, and scanning electron microscopy. In addition Galvano-Inlays which had been in the mouth for two years, were evaluated in the same way. Besides good contact of the fine gold to the tooth, marginal discrepancies in the range of 60 to 160 microns were found which can hardly be improved by means of burnishing. After all, the insufficiency results from the inevitable gap of cementation or from breaking failure of the polished and thus hardened margin of the fine gold.

[Metal-based esthetic inlays]. / Fémvázalapú esztétikus betétek.

The aesthetic appearance and marginal accuracy of porcelain fused to metal inlays/onlays have been evaluated in this study. The metal frameworks of the restorations were fabricated by casting or by galvanic techniques. Both the gold collar and the insufficient thickness of covering porcelain influenced the aesthetic features of inlays negatively. The good aesthetic appearance achieved in case of onlays was independent of manufacturing procedures. Inlays/onlays accomplished by galvanic technique showed a better marginal fitting as compared to that of cast ones.

Influence of immediate dentin sealing techniques on cuspal deflection and fracture resistance of teeth restored with composite resin inlays.

SUMMARY This research evaluated the influence of immediate dentin sealing (IDS) techniques on cuspal deflection and fracture resistance of teeth restored with composite resin inlays. Forty-eight maxillary premolars were divided into four groups: G1, sound teeth (control); G2, without IDS; G3, IDS with Clearfil SE Bond (CSE); and G4, IDS with CSE and Protect Liner F. The teeth from groups 2, 3, and 4 received mesio-distal-occlusal preparations. The impressions were made with vinyl polysiloxane, followed by provisional restoration and storage in water for seven days. The impressions were poured using type IV die stone, and inlays with Filtek Z250 composite resin were built over each cast. The inlays were luted with Panavia F. After storage in water for 72 hours, a 200-N load was applied on the occlusal surface using a metal sphere connected to a universal testing machine, and the cuspal deflection was measured with a micrometer. The specimens were then submitted to an axial load until failure. The following mean cuspal deflection (µm) and mean fracture resistance (N) followed by the same lowercase letter represent no statistical difference by analysis of variance and Tukey (p<0.05): cuspal deflection: G1, 3.1 ± 1.5(a); G2, 10.3 ± 4.6(b); G3, 5.5 ± 1.8(ac); and G4, 7.7 ± 5.1(bc); fracture resistance: G1, 1974 ± 708(a); G2, 1162 ± 474(b); G3, 700 ± 280(b); and G4, 810 ± 343(b). IDS with CSE allowed cuspal deflection comparable with that associated with sound teeth. The application of Protect Liner F did not contribute to a decrease in cuspal deflection. The IDS techniques did not influence the fracture resistance of teeth.

Effect of proximal box elevation with resin composite on marginal quality of resin composite inlays in vitro.

OBJECTIVES: To evaluate marginal quality and resin-resin transition of lab made resin composite inlays in deep proximal cavities with and without 3 mm proximal box elevation (PBE) using resin composites before and after thermo-mechanical loading (TML). METHODS: MOD cavities with one proximal box beneath the cementoenamel junction were prepared in 40 extracted human third molars. Proximal boxes ending in dentine were elevated 3 mm with different resin composites (G-Cem, Maxcem Elite as self-adhesive resin cements and Clearfil Majesty Posterior as restorative resin composite in one or three layers bonded with AdheSE), or left untreated. Clearfil Majesty Posterior inlays were luted with Syntac and Variolink II (n = 8). Marginal quality as well as the PBE-composite inlay interface was analyzed under an SEM using epoxy resin replicas before and after thermomechanical loading (100,000 × 50 N and 2500 thermocylces between +5 °C and +55 °C). RESULTS: Bonding resin composite inlays directly to dentine showed similar amounts of gap-free margins in dentine compared to PBE applied in three consecutive layers (p > 0.05). The groups with self-adhesive resin cements for PBE exhibited significantly more gaps in dentine (p < 0.05). SIGNIFICANCES: With layered resin composite, PBE is effective in indirect resin composite bonding to deep proximal boxes. Self-adhesive resin cements are not suitable for this indication.

Clinical long-term evaluation and failure characteristics of 1,335 all-ceramic restorations.

PURPOSE: The aim of this clinical retrospective study was to evaluate the clinical quality, estimated survival rate, and failure analysis of different all-ceramic restorations in a long-term analysis of up to 20 years. MATERIALS AND METHODS: Different all-ceramic restorations (crowns [n = 470], veneers [n = 318], onlays [n = 213], and inlays ]n = 334[) were placed in 302 patients (120 men, 182 women) between 1987 and 2009 at Medical University Innsbruck, Innsbruck, Austria. Clinical examination was performed during patients' regularly scheduled maintenance appointments. Esthetic match, porcelain surface, marginal discoloration, and integrity were evaluated following modified California Dental Association/Ryge criteria. Number of restoration failures and reasons for failure were recorded. The study population included 106 (35.1%) individuals diagnosed with bruxism. The success rate was determined using Kaplan-Meier survival analysis. RESULTS: The mean observation time was 102 ± 60 months. Ninety-five failures were recorded. The main reason for failure was fracture of the ceramic (33.68%). The estimated survival rate was 97.3% after 5 years, 93.5% at 10 years, and 78.5% at 20 years. Nonvital teeth showed a significantly higher risk of failure (P < .0001). There was a 2.3-times greater risk of failure associated with existing parafunction (bruxism, P = .0045). Cementation using Variolink showed significantly fewer failures than Optec Cement (P = .0217) and Dual Cement (P = .0099). No significant differences were found for type of restoration and distribution in the mouth. CONCLUSION: All-ceramic restorations offer a predictable and successful restoration with an estimated survival probability of 93.5% over 10 years. Significantly increased failure rates are associated with bruxism, nonvital teeth, and specific cementation agents.