Assessment of Decision-Making and Material Selection for Vital Pulp Therapy in Deep Carious Lesions: A Study at the Faculty of Dentistry, King Abdulaziz University.

PURPOSE: The purposes of this study were to assess decision-making, material selection, and management of deep carious lesions in permanent teeth requiring vital pulp therapy (VPT); investigate the intradepartmental and interdepartmental consensus in the management of those cases; and correlate this study's results to the current scientific literature, clinical experience, and postgraduate training among staff and postgraduate students at the Faculty of Dentistry, King Abdulaziz University. MATERIALS AND METHODS: The survey included faculty from pedodontics, endodontics, and restorative/operative dentistry; postgraduate students; and interns, excluding specific categories such as retired faculty, external trainers, non-faculty hospital specialists, general practitioners, students, interns outside the institution, and other departments. An anonymous electronic questionnaire was developed and validated. Ethical approval was obtained, and the questionnaire was distributed to all 148 English-proficient members of the targeted population via email and WhatsApp, accompanied by a cover letter. The questionnaire encompassed demographic, education, experience, assessment, decision-making, and management sections. Data were collected and analyzed using Microsoft Excel, with results presented using categorical variables, Pareto charts, and statistical tests. RESULTS: There were 86 responses, representing 58% of the target population, with the key findings including the prominence of "Pre-operative vitality test result" as the most important factor in assessing deep carious lesions, with no significant differences among specialties. The (one-step and one-visit) management approach was preferred by 50% of participants, with no significant specialty differences. For deep carious lesions without pulpal exposure, glass ionomer (GI)/resin-modified glass ionomer (RMGI) base was the top choice, with no variation among all specialties. In cases with pulpal exposure, the one-visit approach (direct pulp capping (DPC), base, and restoration) was the most favored, with no specialty differences. Material availability significantly influenced decision-making, with no specialty variations. CONCLUSION: The study highlights the crucial role of pre-operative vitality tests in assessing deep carious lesions for VPT or root canal treatment (RCT). Participants generally favored VPT for cases with normal pulp vitality, with some departmental variation. Controlling bleeding post-pulpal exposure was a central concern. Mineral trioxide aggregate (MTA) was the most commonly used VPT material, followed by Ca(OH)2 and Biodentine. Factors such as treatment access, patient compliance, remaining dentin thickness, and oral hygiene had minimal impact on treatment choice. Limited availability of VPT materials was the primary reason for non-use. The survey's acceptable response rate raises concerns about potential non-response bias, though limitations include a lack of data on non-responders. Nevertheless, the survey's strength lies in its comprehensive coverage of key clinical aspects, engaging professionals from diverse specialties and educational levels who are collectively interested in addressing deep caries cases.

Flexural Strength Properties of Five Different Monolithic Computer-Aided Design/Computer-Aided Manufacturing Ceramic Materials: An In Vitro Study.

Objective The purpose of this in vitro study is to compare the flexural strength and Weibull modulus of 5 different monolithic computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics. Methods A total of 50 specimens were fabricated, 10 from each of the following materials: lithium disilicate-based ceramic (IPS e.max CAD), zirconia -reinforced lithium-silicate ceramic (Vita Suprinity), leucite-based glass ceramic (IPS Empress CAD), and two zirconia-based ceramics (Zenostar and CopraSmile). The specimens were 4 mm wide, 2 mm thick, and 16 mm long. Flexural strength test was executed using a universal testing machine (Model 5980, Instron Industrial Products, Norwood, MA, USA). The two-parameter Weibull distribution function was used to analyze the variability of flexural strength values. Statistical analysis was performed on SPSS Version 23 (IBM Corp., Armonk, NY, USA) using one-way analysis of variance (ANOVA) and post-hoc Tukey's test. Results Suprinity had the highest Weibull modulus value, while Empress CAD displayed the lowest value. One-way ANOVA showed significant difference in the flexural strength between the different materials tested (p<0.05). Post-hoc analysis revealed significant differences among all the test groups in terms of flexural strength. Zenostar presented the highest mean flexural strength value (1033.90 MPa), while Empress CAD had the lowest value. Conclusion High-translucency zirconia had superior flexural properties than translucent zirconia, lithium disilicate ceramics, zirconia-reinforced lithium silicate ceramics, and leucite-based glass ceramics.

A self-etch bonding system with potential to eliminate selective etching and resist proteolytic degradation.

OBJECTIVES: Bonded restorations using self-etch (SE) systems exhibit a limited lifespan due to their susceptibility to hydrolytic, enzymatic or fatigue degradation and poor performance on enamel. This study was conducted to develop and assess the performance of a two-step SE system using a functional monomer bis[2-(methacryloyloxy)ethyl]phosphate (BMEP) and demonstrate a strategy to enhance stability of bonded resin composite restorations to both enamel and dentine. METHODS: A two-step SE system was formulated with a primer containing BMEP, with an adhesive with or without BMEP, and compared to a commercial 10-MDP-containing system, ClearfilTM SE Bond 2 (CFSE). The systems were evaluated on enamel for surface roughness and microshear bond strength (µSBS) and on dentine for microtensile bond strength (µTBS), nanoleakage, MMP inhibition and cyclic flexural fatigue. RESULTS: Whilst all bonding systems resulted in statistically similar µSBS, BMEP-based primers yielded greater enamel surface roughness than the CFSE primer. The BMEP-free adhesives resulted in statistically similar or higher µTBS and lower nanoleakage compared to CFSE. In situ zymography revealed minimal to no MMP activity within the hybrid layer of BMEP-based systems. The BMEP-free adhesive exhibited flexural strength and fatigue resistance statistically similar to CFSE. CONCLUSIONS: Incorporation of BMEP in the primer led to satisfactory bond strengths with both enamel and dentine, potentially eliminating the need for selective enamel etching. Combined with an adhesive formulation that is solvent-free and hydrophobic, and confining the acidic functional monomer in the primer resulted in minimal interfacial leakage, and resistance to proteolytic degradation and the cyclic nature of chewing. CLINICAL SIGNIFICANCE: The SE bonding system containing BMEP combines the potent etching of phosphoric acid with the therapeutic function of the phosphate-based monomer in creating a homogenous hybrid layer with protection against endogenous proteolytic enzymes. This strategy may overcome current challenges that arise during selective enamel etching.

Effect of Light Curing Distance on Microhardness Profiles of Bulk-Fill Resin Composites.

Bulk-fill (BF) dental resin composites are made to be polymerized in increments of up to 5 mm rather than the 2 mm increment recommended for conventional composites. This project aimed to determine microhardness (MH) profiles of BF resin composites at different depths and varying light cure (LC) distances from the light source in an attempt to mimic varying clinical situations. Forty-eight cylindrical specimens (4 mm diameter and 6 mm height) were prepared from 3 BF composites: Tetric N-Ceram Bulk-Fill (TBF), Filtek One Bulk-Fill (FBF), and Sonic-Fill 2 (SF2). Four different distances (0, 2, 4, and 6 mm) from the LC unit were investigated. Vickers MH was measured at the top and bottom of the samples and at every 1 mm, by creating 3 indentations at each depth. The bottom-top microhardness ratio (MHR) and percentage reduction in MHR were also measured. Data was analyzed using mixed-model repeated-measure ANOVA at 0.05 significance level. The main variables effects "material, LC distance, and depth" were significant (p < 0.001). Increasing LC distance and the depth of the tested BF significantly affected Vickers MH and MHR. None of the tested BF materials had sufficient MHR at the depths of 4-6 mm. SF2 showed the least MHR reduction.

Efficiency of light curing units in a government dental school.

The light intensity of a light-curing unit is a crucial factor that affects the clinical longevity of resin composites. This study aimed to investigate the efficiency of light-curing units in use at a local governmental dental school for curing conventional and bulk-fill resin materials. A total of 166 light-curing units at three locations were examined, and the brand, type, clinic location, diameter of curing tip, tip cleanliness (using a visual score), and the output (in mW/cm2 using a digital radiometer) were recorded. Only 23.5% of the units examined had clean tips, with the graduate student clinical area containing the highest percentage of clean tips. Further, tips with poor cleanliness score values were associated with significantly lower output intensities. A small percentage (9.4%) of units was capable of producing intensities higher than 1,200 mW/cm2 and lower than 600 mW/cm2 (7.6%). The majority of the low intensity units were located in the undergraduate student area, which also contained the highest number of units with intensities between 900 and 1,200 mW/cm2. The output of all the units in service was satisfactory for curing conventional resin composites, and most units were capable of curing bulk-fill resin materials.

Infection Control Barrier and Curing Time as Factors Affecting the Irradiance of Light-Cure Units.

OBJECTIVE: The objective of the study is to investigate the effect of infection control barrier (ICB) and curing time on irradiance of light cure units (LCUs). METHODS: Irradiance (mW/cm2) of the LCUs at a government dental school were recorded with and without ICB at 0 (T0), 10 (T10), and 20 (T20) seconds using a digital radiometer. Data were analyzed using IBM® SPSS® Statistics Version 17 for Windows software for the analysis of variance and Bonferroni methods at 0.05 significance level. RESULTS: Using ICB resulted in a statistically significant effect on the irradiance mean (P < 0.01). A significant difference existed between the four different brands of LCUs at different time intervals, irrespective of the use of ICB. At T0 and T10, the mean output of Acteon mini-light-emitting diode (LED) was significantly higher than that of either the Kerr Demi Ultra or the Kavo Polylux II. At T20, E-Morlit's mean irradiance was significantly higher than that of Kerr Demi Ultra, which in turn was significantly higher than that of the Kavo PolyLux II. The mean irradiance of the LEDs was significantly higher than that of the halogens irrespective of barrier placement and at all-time points. CONCLUSION: The ICB used in this study resulted in a statistically significant reduction in the irradiance output. No significant difference in the irradiance was found at different curing time intervals for the tested units regardless of ICB usage.

In Vitro Antimicrobial Effectiveness of Root Canal Sealers against Enterococcus faecalis: A Systematic Review.

INTRODUCTION: The purpose of this systematic review was to summarize the outcomes of in vitro studies of root canal sealers for their antimicrobial effectiveness against Enterococcus faecalis on the basis of direct contact test. METHODS: An exhaustive literature search was performed by using MEDLINE, Scopus, TRIP, and OpenThesis databases, followed by an extensive hand search of references of identified articles. Two independent reviewers evaluated the studies for eligibility against inclusion and exclusion criteria and performed data abstraction and risk of bias evaluations. RESULTS: A total of 31 articles were assessed for eligibility. Of these, 24 met the inclusion criteria and were included in the systematic review. A considerable heterogeneity was found in the methodologies of included studies. Therefore, it was not feasible to perform meta-analysis. Majority of the studies reported that different categories of freshly prepared sealers possessed some form of positive antimicrobial activity against E. faecalis for up to 24 hours. Antimicrobial efficacy was lost as the material set. Moderate evidence was found for no antimicrobial activity of aged (2-day to 7-day set) sealer samples across all categories. CONCLUSIONS: The evidence indicated positive antimicrobial activity of freshly mixed sealers against E. faecalis. Antimicrobial efficacy was lost as the material set, with no bacterial growth inhibition by 2-day to 7-day set sealer samples. However, the studies included in this review presented medium to high risk of bias. This review identified the need for the development of standardized methods to evaluate antimicrobial activity of root canal sealers in in vitro studies.

Comparison of Stresses Generated within the Supporting Structures of Mandibular Second Molars Restored with Different Crown Materials: 3-D Finite Element Analysis (FEA).

PURPOSE: This study compares the FEA-calculated stresses generated within the supporting periodontal structure of a mandibular second molar restored with a full ceramic crown and with a porcelain-fused-to-metal (PFM) crown, each resisting occlusal forces acting at different inclinations. MATERIALS AND METHODS: Three-dimensional finite element models representing the crown of an unrestored mandibular second molar and two relevant restoration designs were constructed. Two designs represented the molar restored with a full ceramic crown and with a PFM crown, each cemented with the same resin cement. Occlusion was assumed at three contact areas, which equally shared a 100 N force. The analysis was carried out for forces located in the bucco-axial-lingual plane at five inclinations, 0, 22.5°, 45°, 67.5°, and 90°, measured from the axial direction of the tooth. The magnitudes and sites of the maximum equivalent stress (MES) generated within the supporting periodontium of each analyzed model were collected. RESULTS: Generally, there were no significant differences in the site and magnitude of MES in the regions of the supporting structure for the analyzed models. The MES was located at the tooth periodontal ligament (PDL) bifurcation area and distal root apex, crestal bone at the junction between cortical and cancellous bone, and the distal wall of the mesial root socket of cancellous bone. The highest stresses corresponded to a horizontal load, followed by the axial load in the PDL and cortical zones. The results show opposite observations for the cancellous bone. The lowest stresses were generated under a load inclination between 22.5° and 45°. CONCLUSION: Considering the stresses generated within the supporting structures, the present work validates, by calculation, the proposed clinical use of either a full ceramic crown or a PFM crown as a restoration for mandibular second molars.

Infrared spectroscopic analysis of restorative composite materials' surfaces and their saline extracts.

This study aims at finding out if multiple attenuated internal reflection-infrared (MAIR-IR) spectroscopic analysis can be used as a tool to differentiate commercial resin composite brands and to find out if different resin composites will have different abilities of leaching materials that are cytotoxic to human gingival fibroblasts (HGFs) Tooth-colored resin fillings have become increasingly popular as restorative materials, which make it important to differentiate the commercial brands for forensic and biological purposes. Fourteen resin composite brands were used in the study. MAIR-IR spectroscopic analysis was used for surface characterization of the organic and inorganic parts of the resin composite samples which were studied as is and after 2 weeks of saline incubation. IR spectroscopy was also done on the saline extracts to find out if different resin composite materials would have different leaching abilities. The saline extracts were also used for the viability testing of HGF cell cultures. One-way analysis of variance test statistics was used to analyze the results. It was found that the resin composite brands have different spectra after saline soaking. It was also found that these resin composite brands possess different leaching abilities with regard to the amount and type of materials and different cytotoxic effects, which were found to be threshold dependent, meaning there is a critical or threshold value of leaching material at or above which the toxic effect will be significant and below which there is no toxic effect. Therefore, IR spectroscopy might be considered as a useful tool for dental resin composite characterization. However, more oral simulating environmental testing methods, different surface characterization methods, and more cell viability testing methods and assays must be considered for more specific results which relate more to the behavior of these dental resin composites in the oral environment.

Expanding the Grading of Recommendations Assessment, Development, and Evaluation (Ex-GRADE) for Evidence-Based Clinical Recommendations: Validation Study.

Clinicians use general practice guidelines as a source of support for their intervention, but how much confidence should they place on these recommendations? How much confidence should patients place on these recommendations? Various instruments are available to assess the quality of evidence of research, such as the revised Wong scale (R-Wong) which examines the quality of research design, methodology and data analysis, and the revision of the assessment of multiple systematic reviews (R-AMSTAR), which examines the quality of systematic reviews.The Grading of Recommendation Assessment, Development, and Evaluation (GRADE) Working Group developed an instrument called the GRADE system in order to grade the quality of the evidence in studies and to evaluate the strength of recommendation of the intervention that is proposed in the published article. The GRADE looks at four factors to determine the quality of the evidence: study design, study quality, consistency, and directness. After combining the four components and assessing the grade of the evidence, the strength of recommendation of the intervention is established. The GRADE, however, only makes a qualitative assessment of the evidence and does not generate quantifiable data.In this study, we have quantified both the grading of the quality of evidence and also the strength of recommendation of the original GRADE, hence expanding the GRADE. This expansion of the GRADE (Ex-GRADE) permits the creation of a new instrument that can produce tangible data and possibly bridge the gap between evidence-based research and evidence-based clinical practice.

Osteoimmunopathology in HIV/AIDS: A Translational Evidence-Based Perspective.

Infection with the human immunodeficiency virus-1 (HIV) and the resulting acquired immune deficiency syndrome (AIDS) alter not only cellular immune regulation but also the bone metabolism. Since cellular immunity and bone metabolism are intimately intertwined in the osteoimmune network, it is to be expected that bone metabolism is also affected in patients with HIV/AIDS. The concerted evidence points convincingly toward impaired activity of osteoblasts and increased activity of osteoclasts in patients with HIV/AIDS, leading to a significant increase in the prevalence of osteoporosis. Research attributes these outcomes in part at least to the ART, PI, and HAART therapies endured by these patients. We review and discuss these lines of evidence from the perspective of translational clinically relevant complex systematic reviews for comparative effectiveness analysis and evidence-based intervention on a global scale.