Impact of matrix systems on proximal contact tightness and surface geometry in class II direct composite restoration in-vitro

Current trends in placing posterior composite restorations: Perspectives from Palestinian general dentists: A questionnair study

Aim

The success of composite restorations relies on material selection and practitioner-related factors that shape the overall outcome. This study explores the practices of Palestinian general dental practitioners in placing posterior composites, examining the impact of work sector, experience, and gender on their choices.

Materials and Methods

The study was conducted as an online cross-sectional questionnaire and involved 351 participants, with a response rate of 69.8%. The survey comprised 18 closed-ended questions covering demographics, material selection, and composite placement in special cases, techniques, and factors influencing the choices. Statistical analyses included descriptive statistics, chi-squared tests, and Fisher's exact tests.

Results

Composite was the predominant choice for small-size (83.7%) and large-size posterior cavities (60.4%). Practitioners commonly opted for composite restorations in cases involving occlusal parafunctional activity (60%), poor oral hygiene (78%), and subgingival cavities (72.2%). Only 19.6% and 5.3% reported occlusal and gingival beveling, respectively. Rubber dams for isolation stood at 30%, one-step self-etch adhesives at 44.9%, and the oblique layering technique at 51%. Light-emitting diode curing units were popular (97.55%), but monitoring output with a radiometer was infrequent (93.5%). Tofflemire metal matrix usage was 46.1%, whereas a sectional matrix system was employed by 29.8%. A 2 mm layer exposure to light curing for 20 s was reported by 62%, and 27.75% utilized additional light-curing postmatrix band removal.

Conclusion

The study highlights the need for Palestinian dental professionals to update their clinical approaches in placing composite restorations in posterior teeth. Gender, work sector, and experience influence practitioners' choices, emphasizing the importance of tailored continuing education programs for improving clinical practices.

New Technique for Wedge Selection in Direct Class II Restorations: A Pilot Study

Background: Performing an appropriate Class II direct restoration is a great challenge. The correct selection of the matrix system and the elements used for its stabilization will have a great impact on the result. The aim of this study is to show a new digital method for a predictable selection of the wedge and compare it with the conventional method. Methods: Sixty patients were randomly divided into two groups. In Group 0, the wedge was selected intraoperatively by visual examination, while in Group 1 the wedge was selected preoperatively through the measurement of the cervical embrasure on the bite-wing radiography. The number of wedges used, modifications to them, and tissue damage were registered, along with the quality of the proximal contact and the marginal adaptation. Results: Student's t-test revealed a statistical difference between the number of wedges used, which was higher in Group 0 (p < 0.05). Pearson Chi-square test showed that tissue damage was statistically higher in Group 0 (p < 0.05), while there was no statistically significant difference between groups in wedge modifications (p > 0.05). Group 1 revealed a higher frequency of satisfactory proximal contact and marginal adaptation (p < 0.05). Conclusions: This new technique reduces wedges waste and tissue damage and provides an adequate interproximal anatomy.

Proximal contact tightness of direct Class II composite resin restorations with various matrix systems: A systematic review

Background

Restoring an ideal proximal contact in direct Class II composite resin restorations is challenging due to polymerization shrinkage, absence of condensability of composite materials, thickness of matrix bands, and the use of various separation techniques, retainers, and bands.

Aims

The aim of this study was to evaluate the proximal contact tightness that is achieved by various matrix systems used to restore a direct Class II cavity with composite resin restoration.

Methods

A systematic review was carried out according to the PRISMA 2020 statement guidelines. The online search for the articles was done in electronic databases of MEDLINE/PubMed, Cochrane, and Google Scholar. The articles comparing different matrix systems for restoration were selected. Out of 146 articles, a total of 6 articles met the selection criteria and were included. The QUIN risk-of-bias (RoB) tool was used for assessing the study quality. The data extracted from full text articles selected for inclusion, using a standardized software (Office Excel 2013 Software, Microsoft Corporation, Redmond, WA, USA).

Results and Conclusion

Combination of sectional matrices and separation rings resulted in tighter proximal contact compared to other matrix systems.