Five-year clinical evaluation of universal adhesive applied following different bonding techniques: A randomized multicenter clinical trial

ObjectivesTo evaluate the clinical performance of a universal adhesive system (Futurabond U, Voco) when applied following different adhesive strategies in non-carious cervical lesions (NCCLs) after 5 years.MethodsFifty participants were included. Futurabond U (Voco) was applied in NCCLs using four adhesive strategies (n = 50 each): only self-etch (SE); selective enamel etching + self-etch (SET + SE); etch-and-rinse with dry dentin (ERD); and etch-and-rinse with wet dentin (ERW). All cavities were restored with Admira Fusion composite resin (Voco). Restorations were evaluated after 1, 3, and 5 years using the World Federation criteria (FDI) and the modified United States Public Health Service (USPHS) criteria.ResultsAfter 5 years, retention rates were 81 % (65.8–90.5) for SE, 87 % (73.2–94.4) for SET + SE, 84 % (69.6–92.6) for ERD, and 78 % (63.6–88.9) for ERW (p > 0.05). Thirty-five restorations were considered to have minor discrepancies in marginal adaptation at the 5-year recall (14 for SE, 9 for SET + SE, 6 for ERD, and 6 for ERW; p > 0.05). Sixteen restorations were detected as a minor marginal discoloration (6 for SE, 4 for SET + SE, 1 for ERD, and 5 for ERW; p > 0.05) and one restoration showed a recurrence of caries (1 for ERW; p > 0.05) at the 5-year recall. No restorations showed postoperative sensitivity after 5 years.SignificanceNCCLs restorations using a universal adhesive showed satisfactory clinical performance after 5 years, regardless of the adhesive strategy.     

Effect of calcium silicate-based endodontic sealer on the retention of fiber posts cemented at different time intervals

ObjectiveTo evaluate the effect of BC HiFlow, a new calcium silicate-based endodontic sealer, compared with a resin epoxy-based sealer after 2 different times of cementation on the pull-out bond strength of glass-fiber–reinforced composite posts cemented with a self-adhesive resin cement (RelyX Unicem).MethodologySixty human maxillary central incisors were decoronated, prepared and obturated with gutta-percha and sealer. Roots were distributed into 5 groups according to the sealer and time of post cementation: (1) AH Plus sealer with immediate post fixation, (2) BC HiFlow with immediate post fixation, (3) AH Plus and post fixation after 7 days, (4) BC HiFlow and post fixation after 7 days, and (5) fiber post fixation in canals obturated with gutta-percha only (no sealer). After 1 week of post cementation, the pull-out test was performed and the failure mode was examined under a digital microscope. Data were analyzed using ANOVA followed by Tukey's post hoc and t tests (p < .05).ResultsWith immediate post cementation, AH Plus group showed significantly higher pull-out retentive strength than the BC HiFlow and control groups (p = .009 and p < .001, respectively). There was no significant difference between the groups when the posts were cemented 7 days after obturation (p = .726). The time of post cementation had a significant influence on the canals obturated with AH Plus (p = .003). The time did not significantly affect the canals obturated with BC HiFlow (p = .289). The prominent type of failure was mixed mode in all groups.ConclusionBC HiFlow sealer did not affect the pull-out bond strength of glass-fiber–reinforced composite posts cemented with a self-adhesive resin cement immediately after or 7 days after obturation. For immediate post cementation, AH Plus increased the pull-out bond in comparison to BC HiFlow.     

Photobiomodulation vs NSAIDs in the management of postoperative dentoalveolar pain

BackgroundPostoperative pain, the most common complication of dentoalveolar surgery, is routinely controlled by non-steroidal anti-inflammatory drugs (NSAIDs). However, despite its proven efficacy, the long-term consumption of NSAIDs is associated with several serious and adverse effects. As a result, photobiomodulation (PBM) or low-level laser therapy (LLLT) is used in many treatment modalities to reduce pain, inflammation, and promote healing.Aim of the studyTo compare the analgesic effects of LLLT and Ibuprofen after surgical dental extraction.Materials and methodsA clinical trial study was conducted at Umm Al-Qura University Dental Clinics, involving 46 healthy patients between 20 and 60 years of age. The recruited patients were divided into two groups of 23 patients each. Group 1 (positive control group) was prescribed Ibuprofen and Group 2 (experimental group) was treated with LLLT. The pain was measured on days 1, 2, and 7 using the Numeric Pain Rating Scale (NPRS).ResultsThe mean level of pain decreased with both treatments. On the first postoperative day, the pain level in the laser therapy group was significantly lower than in the control group (U = 62.5, p = 0.024). The results indicated a significant decrease in pain level on the second postoperative day for both the control and experimental groups (Z = ?3.61, p < 0.005, and Z = ?3.1, p = 0.002, respectively). However, the pain level was lower in the control group, although the difference was not statistically significant (U = 79, p = 0.102).ConclusionConsidering the constraints of this study, NSAIDs were found to be significantly better at reducing pain than LLLT.     

Impact of SARS-CoV-2 on saliva: TNF-⍺, IL-6, IL-10, lactoferrin,lysozyme, IgG,IgA, and IgM

ObjectivesUnderstanding the role of certain salivary components, such as TNF-?, IL-6, IL-10, lactoferrin, lysozyme, IgG, IgA, and IgM, in airway defense during the ongoing SARS-CoV-2 pandemic is essential. The salivary immune barrier of patients with COVID-19 may play a role in their prognosis. The present study aims to evaluate the impact of SARS-CoV-2 on saliva composition.MethodsA longitudinal study was carried out with male and female firefighters aged 24–48 years. The study sample (n = 34) was divided into 3 groups: asymptomatic volunteers with a negative polymerase chain reaction (PCR) test for SARS-CoV-2 (group 1, Control, n = 21); patients with symptoms of COVID-19 of less than 7 days’ duration and a diagnosis of SARS-CoV-2 infection by PCR (group 2, COVID-19, n = 13); and recovered patients from group 2 who were free of COVID-19 symptoms for at least 2 months (group 3, post-COVID-19 recovery, n = 13). All groups underwent real-time PCR to detect the presence of SARS-CoV-2, as well as analysis of the salivary concentrations of TNF-?, IL-6, IL-10, lactoferrin, lysozyme, IgG, IgA, and IgM by the ELISA method.ResultsLactoferrin concentrations were significantly decreased in the infected group (COVID-19) when compared to those not infected by SARS-CoV-2 (control) (p = 0.032). IgA concentrations were decreased in the COVID-19 and post-COVID-19 groups compared to the control group (p = 0.005 and p = 0.016, respectively). Comparison of the COVID-19 and post-COVID-19 groups also revealed an increase in IgM concentrations during acute SARS-CoV-2 infection (p = 0.010).ConclusionSARS-CoV-2 alters the composition of the salivary immune barrier.     

Association between rs11362 polymorphism in the beta-defensin 1 (DEFB1) gene and dental caries: A meta-analysis

ObjectivesBeta-defensin 1, encoded by the DEFB1 gene, is an important molecule that confers protection from dental caries. Numerous studies have been conducted on the rs11362 polymorphism in the DEFB1 gene. We evaluated the results from studies that have investigated the association between rs11362 polymorphism and dental caries, through a meta-analysis.MethodsThis meta-analysis was designed according to the PRISMA statement guideline. Electronic databases (PubMed, Web of Science, Scopus, and Cochrane Library) were scanned by two independent researchers. The publication bias was determined by statistical analyses using funnel plot, Egger regression test, and Begg and Mazumdar rank correlation test. Heterogeneity was evaluated using the chi-square test, tau-square, and Higgins I² test. Odds ratio (OR) was used to measure the effect size.ResultsRank correlation and regression procedures showed the absence of publication bias in the meta-analysis (p > 0.05). The DEFB1 rs11362 polymorphism in the heterozygous (CC vs. CT: OR = 2.20, 95% confidence interval (CI): 1.17, 4.10; p = 0.014) and dominant (CC vs. CT + TT: OR = 3.11, 95% CI: 1.18, 8.21; p = 0.022) models in the permanent dentition subgroup showed significant differences. However, there was no significant difference between any model in either the deciduous dentition (p > 0.05) or the mixed dentition subgroups (p > 0.05).ConclusionsThis meta-analysis suggests that the DEFB1 rs11362 polymorphism is associated with dental caries in permanent dentition. Moreover, individuals with the TT genotype were found to have seven times higher risk of dental caries than individuals with the CC genotype. There was no such association or statistical difference observed for deciduous and mixed dentitions.     

A dynamic mechanical method to assess bulk viscoelastic behavior of the dentin extracellular matrix

ObjectivesTo develop a protocol for assessment of the bulk viscoelastic behavior of dentin extracellular matrix (ECM), and to assess relationships between induced collagen cross-linking and viscoelasticity of the dentin ECM.MethodsDentin ECM was treated with agents to induce exogenous collagen cross-linking: proanthocyanidins (PACs) from Vitis vinifera – VVe, PACs from Pinus massoniana - PMe, glutaraldehyde – (GA), or kept untreated (control). A dynamic mechanical strain sweep method was carried out in a 3-point bending submersion clamp at treatment; after protein destabilization with 4 M urea and after 7-day, 6-month, and 12-month incubation in simulated body fluid. Tan δ, storage (E’), loss (E”), and complex moduli (E*) were calculated and data were statistically analyzed using two-way ANOVA and post-hoc tests (α = 0.05). Chemical analysis of dentin ECM before and after protein destabilization was assessed with ATR-FTIR spectroscopy.ResultsSignificant interactions between study factors (treatment vs. time points, p < 0.001) were found for all viscoelastic parameters. Despite a significant decrease in all moduli after destabilization, PAC-treated dentin remained statistically higher than control (p < 0.001), indicating permanent mechanical enhancement after biomodification. Covalently crosslinked, GA-treated dentin was unaffected by destabilization (p = 0.873) and showed the lowest damping capacity (tan δ) at all time points (p < 0.001). After 12 months, the damping capacity of PMe and VVe groups decreased significantly. Changes in all amide IR resonances revealed a partial chemical reversal of PAC-mediated biomodification.SignificanceViscoelastic measurements and IR spectroscopy aid in elucidating the role of inter-molecular collagen cross-linking in the mechanical behavior of dentin ECM.     

Correlation of plasma osteopontin and osteocalcin with lower renal function in dental patients with carotid artery calcification and tooth loss

ObjectivesTo investigate plasma osteopontin (OPN) and osteocalcin (OCN) levels in dental patients with carotid artery calcification (CAC) and determine the correlations between these proteins and renal function and tooth loss.MethodsThe health parameters and number of teeth of 99 participants were recorded. Panoramic radiographs were taken for CAC evaluation, and OPN and OCN levels were measured.ResultsNone of the participants had overt kidney disease, and 14 (14.14%) had CAC. The age, sex, and health profiles of patients with CAC were not different from those without CAC. The OPN and OCN levels in participants with CAC were higher than in those without (p = 0.026 and p = 0.025, respectively). The OPN levels were correlated with the estimated glomerular filtration rate (eGFR) (p = 0.021) and tooth loss (p = 0.027). The OCN levels were correlated with the eGFR (p = 0.002), tooth loss (p = 0.023), blood urea nitrogen (p = 0.040), and creatinine levels (p = 0.031). The median tooth loss in individuals with an eGFR <60 mL/min/1.73 m² was higher than that of individuals with an eGFR ≥60 mL/min/1.73 m² (p = 0.033). In individuals with CAC, tooth loss correlated more strongly with the eGFR, and the correlation between OPN and OCN levels was more apparent.ConclusionDental patients with CAC and increased tooth loss have a greater tendency for decreased renal function, which may be associated with OPN and OCN; thus, these patients should be referred for investigation.     

Tooth-level predictors of tooth loss and exposed bone after radiation therapy for head and neck cancer

BackgroundThe objective of this study was to identify tooth-level risk factors for use during preradiation dental care management to predict risk of tooth failure (tooth lost or declared hopeless) and exposed bone after radiation therapy (RT) for head and neck cancer (HNC).MethodsThe authors conducted a prospective observational multicenter cohort study of 572 patients receiving RT for HNC. Participants were examined by calibrated examiners before RT and then every 6 months until 2 years after RT. Analyses considered time to tooth failure and chance of exposed bone at a tooth location.ResultsThe following pre-RT characteristics predicted tooth failure within 2 years after RT: hopeless teeth not extracted pre-RT (hazard ratio [HR], 17.1; P < .0001), untreated caries (HR, 5.0; P < .0001), periodontal pocket 6 mm or greater (HR, 3.4; P = .001) or equaling 5 mm (HR, 2.2; P = .006), recession over 2 mm (HR, 2.8; P = .002), furcation score of 2 (HR, 3.3; P = .003), and any mobility (HR, 2.2; P = .008). The following pre-RT characteristics predicted occurrence of exposed bone at a tooth location: hopeless teeth not extracted before RT (risk ratio [RR], 18.7; P = .0002) and pocket depth 6 mm or greater (RR, 5.4; P = .003) or equaling 5 mm (RR, 4.7; P = .016). Participants with exposed bone at the site of a pre-RT dental extraction averaged 19.6 days between extraction and start of RT compared with 26.2 days for participants without exposed bone (P = .21).ConclusionsIndividual teeth with the risk factors identified in this study should be considered for extraction before RT for HNC, with adequate healing time before start of RT.Practical ImplicationsThe findings of this trial will facilitate evidence-based dental management of the care of patients receiving RT for HNC. This clinical trial was registered at Clinicaltrials.gov. The registration number is NCT02057510.     

Biochemical and X-ray micro-computed tomographic analyses of critical size bone defects grafted with autogenous bone and mercerized bacterial cellulose membranes salified with alendronate

ObjectivesThis study aimed to evaluate the repair of critical-sized bone defects grafted with autogenous bone and mercerized bacterial cellulose membranes (BCm) salified with alendronate (ALN).MethodsForty-eight male Wistar rats underwent surgery to create a 5 mm-diameter bone defect in the calvarium. The removed bone was particularized, regrafted into the defect, and covered by a BCm according to the group: control group (CG), simply mercerized BCm; group 1 (G1), negatively charged BCm (BCm-CM^-) salified with ALN; and group 2 (G2), positively charged BCm (BCm-DEAE⁺) salified with ALN. Serum samples were collected preoperatively and before euthanasia to analyze osteoprotegerin (OPG), parathyroid hormone (PTH), sclerostin (SOST), and fibroblast growth factor 23 (FGF23) levels. The animals were euthanized after 15 or 60 d. Calvaria were analyzed using quantitative microtomography (μCT).ResultsThere was an increased level of PTH in the CG compared to the G2 group, at day 60 (p = 0.019). When analyzing the same group over time, G1 presented an increased FGF23 level on days 15 and 60 (p < 0.05). CG presented an increase in PTH (p = 0.037) at day 60. The μCT analysis detected increased trabecular separation on day 15 in G2 compared to G1 (p = 0.040).ConclusionsSalification of ionized BCm with ALN had no direct effect on bone repair; however, BCm-CM^- increased the levels of FGF23 over time. BCm-DEAE⁺ decreased PTH levels compared to mercerized BCm. BCm-CM-salified with ALN-induced superior bone quality, with respect to trabecular separation, compared to BCm-DEAE⁺.     

Prophylactic antibiotic regimens in dental implant failure: A systematic review and meta-analysis

BackgroundIn this systematic review and meta-analysis, the authors examine the efficacy of antibiotic prophylaxis (AP) and specific antibiotic regimens for prevention of dental implant failure in patients who are healthy overall.Types of Studies ReviewedThe authors independently conducted electronic database and manual searches to identify randomized controlled trials (RCTs). The authors selected articles on the basis of eligibility criteria and assessed for risk of bias by using the Cochrane Handbook. Implant failure was the primary outcome studied; perimucositis or implantitis, prosthetic failure, and adverse events were secondary outcomes studied. The authors conducted random effects meta-analysis for risk ratios of dichotomous data and used OpenMeta[Analyst] (Center for Evidence Synthesis, Brown School of Public Health) for qualitative assessment of administration schedules.ResultsWith duplicates removed, the authors screened 1,022 abstracts, reviewed 21 full-text articles, and included 8 RCTs that included 2,869 implants in 1,585 patients. Meta-analysis results indicated that AP resulted in a statistically significantly lower number of implant failures for all regimens combined (implant, P = .005; patient, P = .002), as well as preoperative (implant, P = .01; patient, P = .007), pre- and postoperative (implant, P = .04), and postoperative AP only (implant, P = .02), compared with no antibiotics. The authors found no statistically significant differences in analysis of comparative antibiotic treatments or secondary outcomes. The authors identified confounding variables.Conclusions and Practical ImplicationsAlthough meta-analysis results suggested that AP may reduce implant failure, definitive conclusions cannot be achieved yet. The overall nonsignificant differences reported in individual trials, limitations discussed, implant infection outcomes, and antibiotic-associated risks must be considered. Thus, the results for implant failure outcomes may not warrant the indiscriminate use of antibiotics in patients who are healthy who are receiving dental implants. Investigators must conduct large-scale RCTs to determine the efficacy of AP and various regimens, independent of confounding variables.     

Combination of fluorescence visualization and iodine solution-guided surgery for local control of early tongue cancer

The control of enclosed oral epithelial dysplasia is important for the control of oral cancer. Fluorescence visualization and iodine solution are able to detect oral epithelial dysplasia and surrounding oral cancer. The purpose of this study was to clarify the effectiveness of combining fluorescence visualization and iodine solution-guided surgery for early tongue cancer. Participants comprised 264 patients with primary early tongue cancer who underwent surgery. The surgical margin was set at 10 mm outside the clinical tumour, and 5 mm outside the area of fluorescence visualization loss, and 5mm outside the iodine unstained area. The 5-year disease-free survival rate was 87.1% vs 76.1% (P = 0.016) and the 5-year local control rate was 98.6% vs 93.0% (P = 0.008) for combination-guided surgery when compared to conventional surgery. Positive margin rates were 0% for cancer, and 6.5% and 0% for low- and high-grade dysplasia, respectively, with combination-guided surgery (P = 0.257). Multivariate analysis revealed that combination-guided surgery (odds ratio 0.140, 95% confidence interval 0.045–0.437; P < 0.001) and intraoperative frozen section examination (odds ratio 0.302; 95% confidence interval 0.115–0.791; P = 0.015) were significantly associated with local control. The combination of fluorescence visualization and iodine solution are effective in selecting surgical margins for early tongue cancer.     

The influence of periodontal status and serum biomarkers on salivary leptin levels in systemic lupus erythematosus patients

ObjectiveThis study aimed to investigate the influence of periodontal status, clinical data, and serum markers on salivary leptin levels in patients with systemic lupus erythematosus (SLE).MethodsA case–control study was conducted with 38 patients with SLE and 29 healthy controls. Periodontal data included periodontal probing depth (PPD), clinical attachment level (CAL), and gingival bleeding on probing (BOP). Stimulated saliva samples were collected to analyze salivary leptin levels. Clinical and serum data were collected from the SLE group. Statistical analysis included the t-test, Mann–Whitney test, Spearman correlation coefficient, and a structural equation model.ResultsThe SLE group had a lower salivary leptin level than the control group (P = 0.002). The model revealed that SLE had an inverse and independent effect on salivary leptin (standardized estimate =  ? 0.289, P = 0.023). Moreover, salivary leptin level negatively correlated with the serum levels of triglyceride, creatinine, and leukocytes, positively correlated with the serum total cholesterol, but was not significantly correlated with the periodontal status.ConclusionThese findings suggest that patients with SLE have a lower salivary leptin level. In addition, the level of salivary leptin does not appear to be related to periodontal status in patients with SLE.     

In-vitro cytocompatibility of self-adhesive dual-curing resin cements on human mesenchymal stem cells (hMSC) and periodontal ligament cells (PDL-hTERT)

ObjectivesSelf-adhesive dual cured resin cements provide easier clinical application than conventional resin cements but release higher amounts of unreacted monomers, potentially affecting their biocompatibility. This study aimed to compare the cytotoxic effects of self-adhesive dual cured resin cements with two conventional resin cements.MethodsSamples of four resin cements, two self-adhesive dual cured cements (group A: RelyX Unicem, group B: SmartCem), and two conventional resin cements (group C: Panavia 2.0, group D: Variolink Esthetic DC) were prepared with a similar dimension under standardized polymerization conditions and stored in water. For each material 18 samples were used and cell cultures of human mesenchymal stem cells (hMSCs) or periodontal ligament cells (PDL-hTERT) were added under appropriate conditions. One experimental group (group E) was left untreated as control. A cell viability WST test, was performed in each experimental group at day 1, 7, 14 and 21. Moreover, microscopic examination of cells was performed using cell viability staining.ResultsViability of both cell types as determined by WST test was significantly impaired at all time periods by the four different cement materials compared to the untreated control. Comparison between the four materials revealed different inhibition of the viability of both, PDL-hTERT and hMSC cells (group C > group B > group A > group D; p < 0.0001).SignificanceAll resin-based cements caused significant impairment of cell viability, reflecting considerable cytotoxicity. Variolink caused significantly smaller changes of viability than the other tested materials.     

The effect of accelerated aging on crystalline structures and optical properties of different monolithic zirconia: A qualitative systematic review

ObjectiveThis study aimed to systematically review the literature related to the impact of low temperature degradation (LTD) on the crystalline structures and optical properties of different types of dental monolithic zirconia materials.MethodsThe systemic review was performed based on the PRISMA statement. In vitro studies investigating the effect of accelerated aging in autoclave (2 bar pressure 134°C – ISO standard 13356-2008) on the crystalline structure and/or optical properties of Yttria-partially stabilized zirconia (Y-PSZ) were included. Specific search terms were used for peer-reviewed articles published in PubMed, Ovid MEDLINE, and EMBASE databases.ResultsFrom 286 eligible articles, 51 articles were selected for full-text analysis, 10 failed to meet the inclusion criteria, and 41 articles were included in this review. Autoclave aging (30 min – 300 h) results in an increase in monoclinic phase (m) content up to 80% for tetragonal zirconia and reaching saturation after 35 h of autoclave aging. All included articles reported less than 1% of monoclinic phase for cubic zirconia after autoclave aging. Translucency parameter was reported between 2.34 and 19.7 after autoclave aging (4–100 h). For same aging time, contrast ratio ranged between 0.48 and 0.95.SignificanceAn increase in monoclinic phase was reported for tetragonal zirconia, while cubic zirconia demonstrates resistance to LTD. The optical properties for all zirconia materials investigated seem more compromised with increasing aging time.     

The relationship between diabetes and carotid artery calcifications detected via dental cone-beam computed tomography in patients undergoing implant treatment planning

BackgroundThe authors investigated the association between carotid artery calcifications (CACs) detected incidentally on dental cone-beam computed tomographic scans and positive diabetes status.MethodsTwo patient groups were identified retrospectively from a patient database: positive for CACs based on cone-beam computed tomographic scans and positive diabetes status. In addition to demographic characteristics, data including diabetes status and presence, type, and absence of CACs were obtained. A χ² statistical analysis was completed by means of dividing the data into sets of known CAC and known history of diabetes; significance level was P < .05.ResultsTo satisfy the a priori power analysis, records from 2010 through 2021 were used.For the positive CAC group, data were obtained from 288 patients (171 men, 117 women) and 68 patients (24%) had a positive diabetes status at the time of cone-beam computed tomography (P < .001). There were significantly more male patients (n = 47) than female patients (n = 21) with diabetes (χ² = 9.9; P = .002). For the positive diabetes group, data were obtained from 225 patients (149 men, 76 women), and 100 patients (44%) had an identifiable CAC. There were significantly more male patients (n = 73) than female patients (n = 27) with CAC (χ² = 21.2; P < .001).ConclusionsThere was a significant relationship to diabetes for patients with CACs, indicating potential undiagnosed diabetes. Male patients with diabetes are significantly more at risk of developing CACs.Practical ImplicationsPeople with CAC may be at risk of having undiagnosed diabetes and require heightened awareness during implant treatment planning.     

Characterization of silver diamine fluoride cytotoxicity using microfluidic tooth-on-a-chip and gingival equivalents

ObjectiveThis study aims to characterize the cytotoxicity potential of silver diamine fluoride (SDF) on dental pulp stem cells (DPSC) and gingival equivalents.MethodsDPSC cultured on 96-well plates was exposed directly to SDF (0.0001–0.01%) and cell viability (IC₅₀) quantified. Effect of SDF on DPSC viability under flow (with dentin barrier) conditions was evaluated using a custom-designed microfluidic "tooth-on-a-chip”. Permeability of dentin discs (0.5–1.5 mm thickness) was evaluated using lucifer yellow permeation assay. Dentin discs were treated with 38% SDF (up to 3 h), and cell viability (live/dead assay) of the DPSC cultured in the inlet (unexposed) and outlet (exposed) regions of the pulp channel was evaluated. To assess the mucosal corrosion potential, gingival equivalents were treated with 38% SDF for 3 or 60 min (OECD test guideline 431) and characterized by MTT assay and histomorphometric analysis.ResultsDPSC exposed directly to SDF showed a dose-dependent reduction in cell viability (IC₅₀: 0.001%). Inlet channels (internal control) of the tooth-on-a-chip exposed to PBS and SDF-exposed dentin discs showed> 85% DPSC viability. In contrast, the outlet channels of SDF-exposed dentin discs showed a decreased viability of< 31% and 0% (1.5 and ≤1.0 mm thick dentin disc, respectively) (p < 0.01). The gingiva equivalents treated with SDF for 3 and 60 min demonstrated decreased epithelial integrity, loss of intercellular cohesion and corneal layer detachment with significant reduction in intact epithelial thickness (p < 0.05).SignificanceSDF penetrated the dentin (≤1 mm thick) inducing significant death of the pulp cells. SDF also disrupted gingival epithelial integrity resulting in mucosal corrosion.     

Zirconia-ceramic versus metal-ceramic posterior multiunit tooth-supported fixed dental prostheses: A systematic review and meta-analysis of randomized controlled trials

BackgroundThe authors aimed to compare the survival and complication rates of zirconia-ceramic (ZC) versus metal-ceramic (MC) restorative material in multiunit tooth-supported posterior fixed dental prostheses (FDP).Types of Studies ReviewedThe authors conducted a systematic search of randomized controlled trials (RCTs), with no time or language restrictions, up to May 2019 using the MEDLINE (PubMed), Scopus, Web of Science, and Cochrane Central Register of Controlled Trials databases, followed by a manual search.ResultsThe authors included 7 RCTs in the review and 5 RCTs in the meta-analysis. All studies had a low risk of bias. The authors included 330 participants (177 ZC and 173 MC tooth-supported FDP) in the meta-analysis, which revealed a medium-term survival rate of 95.4% (95% confidence interval [CI], 90.5% to 99.1%) for ZC FDP compared with 96.9% (95% CI, 94.3% to 99.4%) for MC FDP, with no significant differences (P = .364). The biological or technical complications did not show statistically significant differences, except in the global ceramic veneering chipping analysis (P = .023; risk difference [RD], 22.3%; 95% CI, 3.0% to 41.6%) and their subanalysis: minor chipping or chipping that can be solved with polishing (P = .044; RD, 19.5%; 95% CI, 0.5% to 38.4%), and major chipping or chipping that needs repair in the laboratory (P = .023; RD, 6.0%; 95% CI, 0.8% to 11.3%).Conclusions and Practical ImplicationsPosterior multiunit ZC restorations are considered a predictable treatment in the medium term, although they are slightly more susceptible to chipping of the veneering ceramic than MC restorations.