The clinical performance of bulk-fill versus the incremental layered application of direct resin composite restorations: a systematic review

22 months follow-up of deep marginal acquisition with thermacut bur in management of deep subgingival interproximal carious lesions: a case report

BACKGROUND

Minimally invasive dentistry is now becoming the forefront of restorative dentistry, involving less traumatic treatment protocols, conservation of tooth structure and surrounding tissues, enhancing the long-term survivability of treated teeth, and improving the overall quality of life for patients.

OBJECTIVE

The current case report was conducted to evaluate acquiring deep subgingival interproximal carious lesions by the mean of thermacut bur gingivectomy, in terms of patient satisfaction through pain evaluation, Bleeding on Probing, Pocket Depth, Crestal Bone Level evaluation, and restoration evaluation using modified USPHS criteria.

MATERIAL AND METHODS

A patient with a deep proximal cavity in the posterior tooth was thoroughly examined and underwent Thermacut Bur Gingivectomy (TBG) after caries removal followed by direct resin composite restoration of the prepared cavity. Patient Satisfaction using a Visual Analogue Scale (VAS) as a primary outcome. Bleeding on Probing (BoP), Probing Depth (PD), and Crestal Bone Level (CBL) as secondary outcomes, and Marginal Integrity using Modified USPHS Criteria as a tertiary outcome, were evaluated at the baseline, immediate post-operative, 6 month, 12 month and 22 month follow-up intervals.

RESULTS

Thermacut bur gingivectomy revealed minimal immediate post-operative pain, minimal time-consuming procedure, minimal (BoP), appropriate (PD) and no need for extra specialty involvement in the treatment of deep interproximal carious lesions in addition to preservation of the alveolar bone crest with excellent restoration margin at different time intervals.

CONCLUSIONS

Thermacut bur gingivectomy can be considered a valid treatment for managing of deep subgingival interproximal carious lesions in vital teeth. Thermacut bur gingivectomy can be introduced as an easy technique for clinicians in the management of deep subgingival interproximal carious lesions, without the need to refer patients to periodontists and without the need for special devices.

Physical and Mechanical Properties of Bulk-fill Resin Composites Submitted to Additional Polymerization for Use in Semi-direct Restorations

Physical and mechanical properties of high-viscosity bulk-fill resin composites submitted to additional polymerization for semi-direct use were evaluated. Filtek Z350 XT, Aura Bulk Fill, Beautifil Bulk Restorative, Filtek One Bulk Fill Restorative, and Tetric N-Ceram Bulk Fill were submitted to additional polymerization to evaluate sorption, solubility, surface microhardness, surface roughness before and after simulated brushing, color stability after coffee staining, flexural strength, elastic modulus, and modulus of resilience. Filtek Z350 XT and Filtek One Bulk Fill Restorative showed higher sorption values, while Aura Bulk Fill showed higher solubility (p<0.0001). Microhardness values were significantly higher for Filtek Z350 XT (p<0.0001). Roughness increased after wear for all resins (p<0.05). All resins exhibited staining, with significantly higher ΔEab, ΔE00, and ΔWID values observed for Beautifil Bulk Restorative (p<0.0001). Flexural strength values were higher for Filtek Z350 XT and Filtek One Bulk Fill Restorative in comparison with the others (p<0.0001). Filtek One Bulk-Fill had higher elastic modulus and modulus of resilience values (p<0.0001). Physical and mechanical properties varied according to the composition. None of the bulk-fill resins showed surface microhardness and roughness properties after brushing similar to or superior to those of the conventional type. Color stability after staining depended on resin composition, with Beautifil Bulk Restorative showing more intense staining.

Color adjustment potential of universal shade bulk-fill resin composites

This study investigates how the cavity depth of restorations influences the color adjustment potential of universal shade bulk-fill resin composites. Standard cavities, with diameters of 4 mm and depths of either 2 or 4 mm, were created at the center of artificial teeth occlusal surfaces. A structural-colored bulk-fill resin composite and two pigment-incorporated universal shade bulk-fill resin composites were used. Each resin composite was placed into the cavity to assess its color adjustment potential in relation to the artificial tooth color. Following application, the resin composites' surfaces were polished using diamond-impregnated silicone polishers. Color difference analysis revealed ΔE*ab values of 3.3-4.6 and 2.2-9.6 for structural-colored resin composites and pigment-incorporated universal shade resin composites, respectively, as well as ΔE00 values of 2.7-3.4 and 1.7-5.8 for these resin composites, respectively. These findings suggest that the tested bulk-fill resin composites' color adjustment potential was influenced by restoration depth.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of select 2023 dental literature to briefly touch on several topics of interest to modern restorative dentistry. Each committee member brings discipline-specific expertize in their subject areas that include (in order of appearance here): prosthodontics; periodontics, alveolar bone, and peri-implant tissues; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine, oral and maxillofacial surgery, and oral radiology; and dental caries and cariology. The authors have focused their efforts on presenting information likely to influence the daily dental treatment decisions of the reader with an emphasis on current innovations, new materials and processes, emerging technology, and future trends in dentistry. With the overwhelming volume of literature published daily in dentistry and related disciplines, this review cannot be comprehensive. Instead, its purpose is to inform and update interested readers and provide valuable resource material for those willing to subsequently pursue greater detail on their own. Our intent remains to assist colleagues in navigating the tremendous volume of newly minted information produced annually. Finally, we hope readers find this work helpful in providing evidence-based care to patients seeking healthier and happier lives.

Teaching posterior composite restorations: A survey of dental schools in Palestine

Aim

This study aimed to assess different aspects of teaching posterior composite restorations in two dental schools in Palestine.

Materials and methods

A questionnaire was emailed to the heads of the operative and conservative dentistry departments to collect detailed information on the teaching practices related to posterior composite restorations. The questionnaire comprised 22 questions structured to collect information on the time dedicated to teaching the topic, competency assessments, future plans for allocating time for each restoration type, relevant indications and contraindications, specific materials and techniques utilized in the application, and fees charged for posterior restorations. The gathered responses were collated in Excel and analyzed.

Results

Both dental schools allocated similar teaching times to posterior composites and amalgam in their preclinical operative dentistry courses. However, there was a greater emphasis on composites in the clinical course than in the preclinical course at both institutions. Despite these differences, both institutions expressed a shared intention to allocate more time to teaching posterior composites while reducing the emphasis on teaching amalgam procedures. Consistency was observed across competency testing, cavity design preferences, and contraindications, with both schools favoring slot-type cavities. Furthermore, uniformity was noted in the management of operatively exposed dentin and matrix techniques, although variations existed in moisture isolation. Notably, both schools taught circumferential and sectional metal matrices but did not teach clear sectional matrices or use of bulk-fill composites. Additionally, the adhesive and light-curing practices remained consistent across both institutions.

Conclusion

The findings of this study indicate that the teaching of posterior composite restorations is consistent across both Palestinian dental schools. Their curricula are aligned with contemporary international practices, demonstrating a strong commitment to modern operative dentistry and adherence to global standards. These findings offer valuable insights for educators and researchers and emphasize the need for ongoing adaptations to maintain high clinical standards.

Clinical Outcomes of Bulk-Fill Resin Composite Restorations: A 10-Year Mapping Review and Evidence Gap Map

OBJECTIVE

To map the evidence regarding the clinical performance of posterior restorations with bulk-fill resin composites and identify research gaps.

MATERIALS AND METHODS

This mapping review was conducted following PRISMA-ScR guidelines for scoping reviews, and its protocol was registered on the Open Science Framework platform. Systematic searches were conducted, considering studies published between 2013 and February 2024 in the PubMed, Embase, and Cochrane databases. Clinical studies investigating the performance of bulk-fill resin composite restorations in class I and/or class II preparations with increments of 4 to 5 mm were included.

RESULTS

A total of 147 articles were identified, and based on the eligibility criteria, 26 studies were selected for descriptive analysis. Of the reviewed studies, 73% (n = 19) investigated high-viscosity bulk-fill composites, while 30% (n = 8) focused on low-viscosity bulk-fill composites. Evaluation periods ranged from 1 week to 10 years. Reported annual failure rates varied from 0% to 3%, with survival rates between 78.9% and 100%.

CONCLUSIONS

Bulk-fill resin composites of high viscosity were the most analyzed in the published studies, with evaluation periods of up to 10 years. The review of available scientific evidence showed clinically acceptable performance for composite bulk-fill restorations, with high survival rates and minimal annual failure rates. There is a need for long-term clinical studies on bulk-fill resin composites.

CLINICAL SIGNIFICANCE

This review demonstrates that both high and low-viscosity bulk-fill resin composites exhibit satisfactory clinical performance, which can help clinicians optimize chairside time. However, it is important to highlight the need for further studies with longer follow-up periods.

24 Months clinical prospective of proximal restorations with repeated preheating bulk fill composite up to ten cycles: randomized controlled trial

This study aimed to clinically evaluate the performance of non-preheated bulk fill resin composite in class II cavities versus one, five and ten-time preheating cycles at 68 °C. Eighty-four recruited participants were randomly allocated into four groups (21 patients per group). One posterior Bulk-fill proximal restoration was performed for each participant according to the preheating cycles where in group I; teeth were restored with non-heated resin composite, group II: One preheating cycle of composite syringe was performed prior restoration, and group III: five preheating cycles while for group IV: Ten preheating cycles were performed. These restorations were clinically evaluated at 6, 12, 18 and 24 months. Statistical analysis was performed using one way ANOVA, with set p-value < 0.05. The results revealed that there was perfect agreement between both observers and observations WK (95% CI) [0.908 (0.780:1.000)] and [0.940 (0.824:1.000)], respectively. All restorations showed acceptable clinical performance with alpha and bravo scores. No replacement was required for any restoration. No statistically significant differences were detected between the control and intervention groups across all parameters during the various evaluation stages. It could be concluded that the clinical performance of ten cycles of repeated preheated bulk fill resin composite was equivalent to that of non-preheating resin composites after 24 months follow-up period, with great improvement in manipulation. Preheating of resin composite could be performed up to ten cycles prior to placement without any clinical adverse consequences on the performance of the restoration.

Efficiency of bulk-fill versus conventional resin-based composite in class II restorations: A dental student perspective

Purpose/objectives

The aim of the study was to evaluate the effect of two distinct light-polymerization protocols, used by dental students, on the placement time and polymerization efficiency of bulk-fill (BF) and conventional (CRC) resin-based composites (RBCs).

Methods

Thirty dental students participated in this study. Each student was asked to complete four Class II RBC restorations using two different types of RBCs (BF and CRC) paired with two distinct light-polymerization protocols: one using 1200 mW/cm2 irradiance (P1200) and one using 800 mW/cm2 irradiance (P800). Manufacturer instructions for curing times relative to these irradiance levels were adhered to. The restorations were retrieved, sectioned and Vickers microhardness (VMH) was measured at specific reading points. The placement time was recorded for each procedure. Multivariate analysis of variance and Bonferroni post hoc test were used for data analysis.

Results

Bulk-fill RBCs were associated with significantly shortened placement times (P < 0.001). VMH values of CRC-P800 were significantly higher compared to all other groups (P < 0.02). Across all groups tested, the VMH values at the deepest reading points exceeded those at the occlusal surfaces by over 80 %.

Conclusions

The use of BF RBCs with a P1200 light-polymerization protocol reduced students' procedural times while maintaining effective polymerization of the restorations.

Postoperative sensitivity of composites using novel Bacillus subtilis nanofortified adhesives: a triple-blind study

NANOTECHNOLOGY: is the art and science of dealing with nanoscale particles. This has transformed contemporary dental practices through myriad contributions to biomaterial science. Titanium dioxide nanoparticles procured from Bacillus subtilis, an eco-friendly and biogenic source, can significantly magnify the physiochemical attributes of dental materials. However, postoperative sensitivity is a major drawback of composite restorations. The incorporation of these nanoparticles into dental adhesives can greatly benefit clinical dentistry by resolving this issue. This trial aimed to evaluate the effectiveness of a novel titanium dioxide nanofortified adhesive on the postoperative sensitivity of composite restorations.

METHODS

This triple-blind, parallel-group randomized controlled trial was conducted at the Department of Operative Dentistry and Endodontics, School of Dentistry, Islamabad, from May 15, 2023, to November 25, 2023. Participants (n = 60) with Class I and II primary carious lesions with a minimum cavity depth of 3-5 mm were randomly assigned to two groups (n = 30). After obtaining informed consent, the restorative procedure was accomplished using a minimally invasive approach and etch-and-rinse adhesive strategy. In group A, a nanofortified adhesive was used for composite restoration, whereas in group B, an adhesive without nanoparticles was used. Postoperative sensitivity was evaluated using the Visual Analog Scale (VAS) score at follow-up periods: of one day, one week, two weeks and one month. A Chi-square test was used to compare postoperative sensitivity between the two groups. The level of significance was set at p < 0.05.

RESULTS

A noteworthy association was observed between sensitivity and the group variable at all four evaluation periods: after one day (p = 0.002), 1 week (p = 0.002), 2 weeks (p = 0.007) and one month. In conclusion, participants who underwent restorative intervention using titanium dioxide nanoreinforced adhesives reported a notable reduction in sensitivity at all time intervals. Hence, the occurrence and severity of postoperative sensitivity are significantly reduced using Bacillus subtilis-procured nanofortified adhesives as compared to conventional adhesives without nanoparticles.

TRIAL REGISTRATION

This trial was retrospectively registered at ClinicalTrials.gov (ID: NCT06242184) on 03/02/2024. All procedures involving human participants were performed in conformance with this protocol.

Comparison of Bulk Polymeric Resin Composite and Hybrid Glass Ionomer Cement in Adhesive Class I Dental Restorations: A 3D Finite Element Analysis

This study aimed to investigate the mechanical behavior of resin composites and hybrid glass ionomer cement in class I adhesive dental restorations under loading and shrinkage conditions. Three CAD models of a mandibular first molar with class I cavities were created and restored with different techniques: a bi-layer of Equia Forte HT with Filtek One Bulk Fill Restorative composite (model A), a single layer of adhesive and Filtek One Bulk Fill Restorative (model B), and a single layer of Equia forte HT (model C). Each model was exported to computer-aided engineering software, and 3D finite element models were created. Models A and B exhibited a similar pattern of stress distribution along the enamel-restoration interface, with stress peaks of 12.5 MPa and 14 MPa observed in the enamel tissue. The sound tooth, B, and C models showed a similar trend along the interface between dentine and restoration. A stress peak of about 0.5 MPa was detected in the enamel of both the sound tooth and B models. Model C showed a reduced stress peak of about 1.2 MPa. A significant stress reduction in 4 mm deep class I cavities in lower molars was observed in models where non-shrinking dental filling materials, like the hybrid glass ionomer cement used in model C, were applied. Stress reduction was also achieved in model A, which employed a bi-layer technique with a shrinking polymeric filling material (bulk resin composite). Model C's performance closely resembled that of a sound tooth.

A Historical Perspective on Dental Composite Restorative Materials

This review article will discuss the origin of resin-based dental composite materials and their adoption as potentially useful adjuncts to the primary material used by most dentists for direct restorations. The evolution of the materials, largely driven by the industry's response to the needs of dentists, has produced materials that are esthetic, strong, and versatile enough to be used in most areas of the oral cavity to replace or restore missing tooth structures. Significant advancements, such as the transition from chemical to light-curing materials, refinements in reinforcing particles to produce optimum polishing and wear resistance, formulating pastes with altered viscosities to create highly flowable and highly stiff materials, and creating materials with enhanced depth of cure to facilitate placement, will be highlighted. Future advancements will likely reflect the movement away from simply being a biocompatible material to one that is designed to produce some type of beneficial effect upon interaction within the oral environment. These new materials have been called "bioactive" by virtue of their potential effects on bacterial biofilms and their ability to promote mineralization of adjacent tooth structures.

The clinical performance of dental resin composite repeatedly preheated: A randomized controlled clinical trial

OBJECTIVES

To assess the clinical performance of class II restorations performed by repeatedly preheated resin composite "RC" at 68 °C up to ten times.

METHODS

105 patients were selected and randomized into three groups, each comprising 35 patients. Each patient was provided with a single class II Bulk-fill resin composite "BF-RC" posterior restoration based on the number of preheating cycles; group I (H0): The BF-RC was packed non-heated, group II (H1): BF-RC preheated once, and group III(H10): BF-RC preheated ten cycles. These restorations were evaluated at 1, 3,6, and 12 months, using the modified United States Public Health Service "USPHS". Statistical analysis was performed using Kruskal-Wallis test, Mann Whitney U test, and Friedmann test, where p = 0.05.

RESULTS

All the 105 restorations did not suffer from any clinical situation that recommended replacement regarding retention, fracture, secondary caries, or anatomical form. Although all performed restorations did have Alpha and Bravo scores with good clinical performance, the non-preheated RC restorations"" suffered from relatively inferior clinical performance through the follow-up period regarding marginal adaptation, marginal discoloration, and color matching when compared to preheated groups. One and ten times of preheating conducted better clinical performance.

CONCLUSIONS

After 12-months follow-up, although no restoration needed replacement or repair in the 3 tested groups, restorations with single and ten times of preheating aided in better clinical performance of RC restorations compared to the non-preheated restorations. Preheating of RC for 10 times could be used safely with good clinical performance of restorations.

CLINICAL SIGNIFICANCE

By continually preheating RC syringe up to ten times, the dentist will not only benefit from the enhanced clinical performance and easiness of application but also will use preheated RC syringes without hesitation, relying on the absence of drawbacks related to multiple preheating cycles.

Impact of repeated preheating of bulk-fill resin composite on postoperative hypersensitivity; a randomized controlled clinical trial

BACKGROUND

This clinical study was conducted aiming to evaluate the impact of repeated preheating of bulk-fill resin composite on postoperative hypersensitivity.

METHODS

A total of 105 eligible, consenting adults were recruited. Patients had posterior teeth suffering from proximal decay with no signs of irreversible pulpitis. Patients were prepared for Class II restorations and restored with bulk-fill resin composite. Patients were randomized into three groups of 35 patients according to the number of preheating cycles for the resin composite syringe used; group I: no preheating; control group at room temperature, group II: Resin composite preheated once, and group III: Resin composite preheated ten cycles. Patients were assessed for postoperative dentin hypersensitivity using the visual analogue scale (VAS) at three-time intervals: day one, one week and by the end of one month after restorative treatment. Statistical analysis was performed; ANOVA with a single factor was used to test for significance at a p value ≤ 0.05. For nonparametric data, the Kruskal‒Wallis test was used to compare the three testing groups. Friedman's test was used to study the changes within each group. Dunn's test was used for pairwise comparisons when the Kruskal‒Wallis test or Friedman's test was significant.

RESULTS

The scores of the three groups through the three time intervals were almost zero except for the first day where VAS scores were recorded with maximum score of 3 for groups I and II. Groups II and III; there was no statistically significant change in hypersensitivity scores by time with P-values 0.135 and 0.368, respectively. However, for group I there was a significant difference from VAS score recorded on first day and the two following time intervals.

CONCLUSION

The repeated preheating cycles of bulk-fill resin composite prior to curing had no adverse effect on the patients regarding postoperative dentin hypersensitivity. This information could be of utmost significance, as the same resin composite syringe can undergo numerous preheating cycles clinically before it is completely consumed with the advantage of improvement on the handling properties.

TRIAL REGISTRATION

The protocol of the current study was registered at www.

CLINICALTRIALS

gov , with the identification number NCT05289479 on 21/03/2022. All procedures involving human participants were performed in accordance with the ethical standards of the Research Ethics Committee of the Faculty of Dentistry, Minia University, Egypt, under the approval number 73/440 on 11/09/2020.

Procedure time and filling quality for bulk-fill base and conventional incremental composite techniques-A randomised controlled in vitro trial

OBJECTIVES

The aims of this randomised controlled laboratory trial were to determine the procedure time and immediate quality (surface porosity and marginal gaps) of fillings placed using the bulk-fill base technique and the conventional incremental technique in simulated clinical settings.

METHODS

Forty-two dentists and dental students were randomly allocated to use either the bulk-fill base technique or the conventional incremental technique to fill an identical class II disto-occlusal cavity in a maxillary left first molar typodont tooth. We recorded the time the participants used to fill the cavity and evaluated the surface porosity and marginal gaps on the approximal surfaces of the fillings using a stereomicroscope and specific probes according to the FDI criteria for restoration evaluation. Data were analysed using the Mann-Whitney U, Kruskal-Wallis, and chi-square tests.

RESULTS

The median time ± interquartile range was 186 ± 80 s for the bulk-fill base technique and 463 ± 156 s for the conventional incremental technique (p < 0.001). The quality of the fillings was better for the bulk-fill base technique than for the conventional incremental technique (X2 = 9.5, p = 0.002). Neither operator experience nor the usual technique of choice were associated with the procedure time or the quality of the fillings.

CONCLUSIONS

Compared to the conventional incremental technique, the use of the bulk-fill base technique shortened the time to fill a cavity by 59.8 % or 4 min and 36 s, and it improved the immediate surface and marginal quality of the fillings, regardless of the operator's experience or technique preference.

CLINICAL SIGNIFICANCE

The use of the bulk-fill base technique instead of the conventional incremental technique leads to significant time-savings when placing large class II composite fillings. Additionally, the use of the bulk-fill base technique instead of the conventional incremental technique improves the immediate quality of large class II composite fillings.