3-Year clinical evaluation of posterior packable composite resin restorations

Physical Properties and Clinical Performance of Short Fiber Reinforced Resin-based Composite in Posterior Dentition: Systematic Review and Meta-analysis

OBJECTIVE

This study compares the physical properties and clinical performance of short fiber reinforced composites (SFRC) to those of particulate-filled resin-based composites (PFRC) for class I and II direct restorations in permanent dentition.

METHODS

Systematic review and meta-analysis was conducted using PubMed, Embase (Elsevier), and Dentistry and Oral Sciences Source (EBSCO) databases. The outcomes evaluated were physical properties including flexural strength, flexural modulus, elastic modulus, microhardness, shrinkage, fracture toughness, degree of conversion, and depth of cure. Clinical performance was evaluated with a systematic review.

RESULTS

The meta-analyses favored SFRC for flexural strength and fracture toughness compared to every PFRC subgroup, with a high quality of evidence. For all other properties, the meta-analyses favored SFRC to overall PFRC, with some non-significant differences with certain PFRC subgroups. The most recent clinical trial showed SFRC performed similarly to PFRC, however older studies suggest inferior surface texture and discoloration of SFRC compared to PFRC.

CONCLUSION

This study can aid dental professionals in clinical decision making, supporting that SFRC offers improved physical properties, especially fracture resistance and flexural strength, compared to PFRC.

Evidence-based clinical practice guideline on restorative treatments for caries lesions: A report from the American Dental Association

BACKGROUND

An expert panel convened by the American Dental Association (ADA) Council on Scientific Affairs together with the ADA Science and Research Institute's program for Clinical and Translational Research conducted a systematic review and developed recommendations for the treatment of moderate and advanced cavitated caries lesions in patients with vital, nonendodontically treated primary and permanent teeth.

TYPES OF STUDIES REVIEWED

The authors searched for systematic reviews comparing carious tissue removal (CTR) approaches in Ovid MEDLINE, Embase, Cochrane Database of Systematic Reviews, and Trip Medical Database. The authors also conducted a systematic search for randomized controlled trials comparing direct restorative materials in Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform. The authors used the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the certainty of the evidence and formulate recommendations.

RESULTS

The panel formulated 16 recommendations and good practice statements: 4 on CTR approaches specific to lesion depth and 12 on direct restorative materials specific to tooth location and surfaces involved. The panel conditionally recommended for the use of conservative CTR approaches, especially for advanced lesions. Although the panel conditionally recommended for the use of all direct restorative materials, they prioritized some materials over the use of others for certain clinical scenarios.

PRACTICAL IMPLICATIONS

The evidence suggests that more conservative CTR approaches may decrease the risk of adverse effects. All included direct restorative materials may be effective in treating moderate and advanced caries lesions on vital, nonendodontically treated primary and permanent teeth.

Direct materials for restoring caries lesions: Systematic review and meta-analysis-a report of the American Dental Association Council on Scientific Affairs

BACKGROUND

The goal of restoring caries lesions is to protect the pulp, prevent progression of the disease process, and restore the form and function of the tooth. The purpose of this systematic review was to determine the effect of different direct restorative materials for treating cavitated caries lesions on anterior and posterior primary and permanent teeth.

TYPE OF STUDIES REVIEWED

The authors included parallel and split-mouth randomized controlled trials comparing the effectiveness of direct restorative materials commercially available in the United States placed in vital, nonendodontically treated primary and permanent teeth. Pairs of reviewers independently conducted study selection, data extraction, and assessments of risk of bias and certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation approach. The authors conducted pair-wise meta-analyses to summarize the evidence and calculated measures of association and their 95% CIs.

RESULTS

Thirty-eight randomized controlled trials were eligible for analysis, which included data on Class I and Class II restorations on primary teeth and Class I, Class II, Class III, Class V, and root surface restorations on permanent teeth. Included studies assessed the effect of amalgam, resin composite, compomer, conventional glass ionomer cement, resin-modified glass isomer cement, and preformed metal crowns. Moderate to very low certainty evidence suggested varying levels of effectiveness across restorative materials.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Owing to a relatively low event rate across various outcomes indicating restoration failure, there was limited evidence to support important differences between direct restorative materials used in practice.

Review of nanomaterials in dentistry: interactions with the oral microenvironment, clinical applications, hazards, and benefits

Interest in the use of engineered nanomaterials (ENMs) as either nanomedicines or dental materials/devices in clinical dentistry is growing. This review aims to detail the ultrafine structure, chemical composition, and reactivity of dental tissues in the context of interactions with ENMs, including the saliva, pellicle layer, and oral biofilm; then describes the applications of ENMs in dentistry in context with beneficial clinical outcomes versus potential risks. The flow rate and quality of saliva are likely to influence the behavior of ENMs in the oral cavity, but how the protein corona formed on the ENMs will alter bioavailability, or interact with the structure and proteins of the pellicle layer, as well as microbes in the biofilm, remains unclear. The tooth enamel is a dense crystalline structure that is likely to act as a barrier to ENM penetration, but underlying dentinal tubules are not. Consequently, ENMs may be used to strengthen dentine or regenerate pulp tissue. ENMs have dental applications as antibacterials for infection control, as nanofillers to improve the mechanical and bioactive properties of restoration materials, and as novel coatings on dental implants. Dentifrices and some related personal care products are already available for oral health applications. Overall, the clinical benefits generally outweigh the hazards of using ENMs in the oral cavity, and the latter should not prevent the responsible innovation of nanotechnology in dentistry. However, the clinical safety regulations for dental materials have not been specifically updated for ENMs, and some guidance on occupational health for practitioners is also needed. Knowledge gaps for future research include the formation of protein corona in the oral cavity, ENM diffusion through clinically relevant biofilms, and mechanistic investigations on how ENMs strengthen the tooth structure.

A 6-year prospective evaluation of a one-step HEMA-free self-etching adhesive in Class II restorations

OBJECTIVE

The aim of this study was to evaluate the clinical effectiveness of a one-step HEMA-free self-etching adhesive (SEA) placed with a micro-fine hybrid resin composite in Class II restorations. The restorations were compared intraindividually with 2-step HEMA containing SEA-giomer restorations.

MATERIAL AND METHODS

Fifty-four patients with at least one pair of two similar Class II cavities participated (30 men, 24 women; mean age 57.1yrs). A total of 115 Class II composite restorations were placed with (1) a one step HEMA-free adhesive and a micro-fine hybrid resin composite (Gbond/Gradia Direct: 60; GG) and (2) a 2-step HEMA-containing SEA and a giomer (FL Bond/Beautifil: 55; FB). Each participant received in a randomized way at least one restoration with each of the experimental materials. The restorations were evaluated at baseline and yearly during a 6 year followup using modified USPHS criteria.

RESULTS

During the 6 years, 111 restorations could be evaluated. No post-operative sensitivity was reported by the participants. Fourteen failed restorations (12.6%) were observed during the follow up, 5 GG (8.5%; 4 premolar and 1 molar teeth) and 9 FB (17.7%; 1 premolar and 8 molar teeth) (p<0.05). Annual failure rate at 6 years were 1.4% for GB and 3.0% for FB. Main reasons of failure were bulk fracture of resin composite for FB and tooth fracture for GB.

SIGNIFICANCE

The HEMA-free SEA-hybrid RC restorations showed good clinical durability in Class II cavities after 6 years. The HEMA-containing SEA-giomer restorations showed a rather high failure frequency.

Randomized Clinical Trial of Four Adhesion Strategies: 18-Month Results

Clinical Relevance

SUMMARY

Statement of the Problem

With Institutional Review Board approval, 39 patients who needed restoration of noncarious cervical lesions (NCCLs) were enrolled in this study. A total of 125 NCCLs were selected and randomly assigned to four groups: 1) a three-step etch-and-rinse adhesive, Adper Scotchbond Multi-Purpose (MP, 3M ESPE, St Paul, MN, USA); 2) a two-step etch-and-rinse adhesive, Adper Single Bond Plus (SB, 3M ESPE); 3) a two-step self-etch adhesive, Adper Scotchbond SE (SE, 3M ESPE); and 4) a one-step self-etch adhesive, Adper Easy Bond (EB, 3M ESPE). A nanofilled composite resin was used for all restorations. Restorations were evaluated at six months and 18 months using modified U.S. Public Health Service (USPHS) parameters.

Results

At six months after initial placement, 107 restorations (85.6% recall rate) were evaluated. At 18 months, 94 restorations (75.2% recall rate) were available for evaluation. The 6 mo/18 mo overall retention rates (%) were 100/90.9 for MP; 100/91.7 for SB; 100/90.9 for SE; and 96.4/92.3 for EB with no statistical difference between any pair of groups at each recall. Sensitivity to air decreased significantly for all adhesives from the preoperative to the postoperative stage and was stable thereafter. Interfacial staining did not change statistically from baseline to six months; however, interfacial staining at the enamel margins was statistically worse at 18 months than at baseline for the two self-etch adhesives EB and SE. Marginal adaptation was statistically worse at 18 months compared with baseline only for EB. This tendency was already significant at the six-month recall.

Conclusion

Although 18-month retention was similar for the different adhesion strategies, enamel marginal deficiencies were more prevalent for the self-etch adhesives.

Morphological analysis of proximal contacts in class II direct restorations with 3D image reconstruction

OBJECTIVES

To evaluate the proximal contact on class II composite restorations constructed using various restorative approaches by a morphological analysis.

METHODS

Sixty plastic premolar teeth were prepared for class II cavities. These teeth were divided into six groups and restored using different materials and matrix systems. Two composite materials used were a microhybrid composite Filtek Z100 (3M/ESPE) and a packable composite P60 (3M/ESPE). Three interproximal matrix systems were two circumferential metal matrices (0.05 mm and 0.03 mm thin, respectively) combined with a Tofflemire retainer, and a pre-contoured sectional matrix system (Palodent). The contact morphologies of the restorations were visually inspected with regard to their buccolinugal and mesiodistal aspects. The contact tightness was measured by inserting different amounts of metal strips. For quantitatively morphologic analysis, three-dimensional (3D) scans of proximal contacts were performed. The results were analysed with two-way ANOVA and the Tukey test.

RESULTS

Under visual observation, contact surfaces in sectional matrix groups showed anatomic profile but concave in the centre, whilst the circumferential matrix groups showed flat profiles. The sectional matrix improved the contact tightness. The 3D analysis revealed that the matrix system was correlated with the contact morphology, since the sectional matrix generated significantly deeper and wider surface concavity.

CONCLUSIONS

All the interproximal matrix systems presented some deficiency in either the contact tightness or contours. Although the sectional matrix system enhanced contact tightness, it caused contact concavity by formation of interproximal marginal overhang. The quantitative morphologic analysis helps to examine improper proximal contact and the associated problems.

Clinical Evaluation of Resin-based Composites in Posterior Restorations: Two-year Results

Nanohybrid and low-shrinkage posterior resin composites, placed with self-etch adhesive systems in posterior teeth, showed satisfactory and similar results after two years.

Eighteen-month clinical evaluation of microhybrid, packable and nanofilled resin composites in Class I restorations

The aim of this article was to report the results of an 18-month longitudinal randomized clinical trial that evaluated the clinical performance of microhybrid, packable and nanofilled resin composite restorations placed in Class I cavities of molar teeth. Three Class I resin composite restorations were placed in each of 35 patients. Each patient received one microhybrid ('Point 4'; Kerr, Orange, CA, USA), one packable ('Packable Premise'; Kerr, Orange, CA, USA) and one nanofilled ('Nanofilled Premise'; Kerr, Orange, CA, USA) resin composite restoration. Clinical evaluation was performed at baseline (2 weeks after placement), and after 6, 12 and 18 months after placement using modified Ryge criteria. No patients were lost from the study. At the final appointment (after 18 months), 95.4%, 93.7% and 96.2% respectively of the microhybrid ('Point 4'), packable ('Packable Premise' and nanofilled ('Nanofilled Premise') resin composite restorations received Alfa ratings. Regardless of the type of restorative material, no significant changes were observed in the modified Ryge criteria at the baseline and 18-month recalls (P <or=0.05). Three restorations (one from each group) exhibited post-operative sensitivity at the baseline and 6-month appointment. After 18 months, one packable resin composite restoration failed because of secondary caries, while secondary caries was not detected on any of the other restorations. The clinical performance of microhybrid ('Point 4'), packable ('Packable Premise') and nanofilled ('Nanofilled Premise') resin composite restorations was acceptable after 18 months. Further studies with longer follow-up periods are recommended to investigate the long-term survival of these restorations.

Six-year Clinical Evaluation of Packable Composite Restorations

As a posterior composite, Filtek P60 exhibited very good clinical performance in Class II cavities for six years.

In vitro bonding performance of self-etch adhesives: II--ultramorphological evaluation

OBJECTIVE

To study the interfacial ultra-morphology formed by "all-in-one" self-etch adhesives.

METHODS

Forty-nine extracted molars were assigned to one of five all-in-one adhesives: Adper Prompt L-Pop (AP, 3M ESPE); Clearfil S3 Bond (S3, Kuraray); G-Bond (GB, GC America); iBond (iB, Heraeus Kulzer) and Xeno IV (XE, Dentsply Caulk). Adper Single Bond Plus (SB, 3M ESPE), a two-step etch&rinse adhesive, and Clearfil SE Bond (SE, Kuraray), a two-step self-etch adhesive, were used as controls. Dentin, unground enamel and ground enamel were used as bonding substrates. Dentin specimens were processed for FESEM and TEM analyses. Enamel specimens were processed for FESEM.

RESULTS

Dentin: GB, iB, S3, SE and XE resulted in a submicron-thick hybrid layer (0.2-0.7 microm), but only S3 and SE did not result in interfacial gaps. AP resulted in the thickest hybrid layer (1.7-2.9 microm) among the self-etch adhesives. SB resulted in a 3.4-5.2 pm thick hybrid layer. Unground enamel-GB, iB and SE resulted in a mostly featureless morphology resembling that of untreated enamel with areas in which the superficial enamel layer was removed without dissolving the subsurface enamel. XE resulted in areas of intra-prismatic etching and areas without any etching pattern. S3 resulted in frequent shallow intra-prismatic etching, while AP was able to unveil the enamel crystallites across the entire enamel surface. Phosphoric acid in SB resulted in the deepest intra- and inter-prismatic demineralization. Ground enamel--AP resulted in a well-defined inter-prismatic etching pattern. iB, GB, SE and S3 resulted in islands of superficially dissolved enamel within areas without evidence of enamel dissolution. XE resulted in etched enamel areas with mild intraprismatic exposure of crystallites. Phosphoric acid in SB resulted in deep enamel etching.

CONCLUSIONS

Only AP, an aggressive self-etch adhesive, showed enamel morphological features that resemble those created by etch & rinse adhesives. S3 and SE were the only self-etch adhesives that did not result in dentin interfacial debonding.

Effect of restoration size on the clinical performance of posterior "packable" resin composites over 18 months

Fifty predominantly moderate or large Class II or multiple-surface Class I resin composite restorations were placed in molars under rubber dam isolation. The restorative systems used were: Alert Condensable (Jeneric/Pentron) and SureFil (Dentsply/Caulk). The restorations were classified according to size, with 7 small, 25 moderate and 18 large, of which 8 were cusp replacement restorations. Baseline, 6, 12 and 18-month double-blinded clinical evaluations were carried out using modified USPHS criteria. The independent variables: restorative material, restoration size and three other clinical factors, were tested using a Multiple Logistic Regression procedure to determine if any were predictive of failure. Of the 50 restorations, four failed by the 18-month recall, three failed due to fracture of the restoration and one due to secondary caries. Both restorative systems demonstrated a 92% success rate. No association between restoration size (p = 0.99) or restorative material (p = 0.65) and failure was found. Similarly, the additional variables, occlusal contact type, presence of occlusal wear facets and first or second molar, were not predictive of failure.

Clinical evaluation of two packable posterior composites: 2-year follow-up

The clinical performance of two packable posterior composites, Alert (A)-Jeneric/Pentron and SureFil (S)-Dentsply, was evaluated in 33 patients. Each patient received one A and one S restoration, resulting in a total of 66 restorations. The restorations were placed by one operator according to the manufacturer's specifications and were finished and polished after 1 week. Photographs were taken at baseline and after 2 years. Two independent evaluators conducted the clinical evaluation by using modified United States Public Health Service criteria. After 2 years, 60 restorations (30 A and 30 S), 27 class I (16 A and 11 S) and 33 class II (14 A and 19 S) were evaluated in 30 patients. Criterion A for recurrent caries, vitality, and retention was applicable to all 60 restorations. Criterion B was distributed among 40 restorations as follows: surface texture (15 A; 2 S), color (5 A; 6 S), postoperative sensitivity (1 S), marginal discoloration (8 A), marginal adaptation (3 A), and wear resistance (2 A). Data were analyzed using the Exact Fisher and McNemar tests. After 2 years, S showed a significantly better performance than A with respect to surface texture and marginal discoloration. The clinical performance of both materials was considered acceptable over the 2-year period. Further evaluations are necessary for a more in-depth analysis.