OBJECTIVE:This study aims to develop and evaluate machine learning (ML) models predicting headache at 40 years of age using longitudinal data from the 1982 Pelotas Birth Cohort, Brazil. METHODS:Analysis included 2,963 participants followed from birth to age 40. The outcome of interest was self-reported headache at age 40, ascertained by a standardized yes/no item. Predictors spanning sociodemographic, lifestyle, sleep, diet, mental health, and orofacial pain domains over the life course were used. Five supervised ML algorithms were evaluated: XGBoost, CatBoost, Random Forest, LightGBM, and TabPFN, benchmarked against multivariable logistic regression. Model performance was primarily assessed using the area under the ROC curve, with accuracy, precision, recall, and F1-score also reported. Data analysis was conducted in Python, with the database split into training (70%) and test (30%) sets. Model interpretability was assessed using Shapley values. RESULTS:Self-reported headache was reported by 1,275 individuals (43.0%). The tuned XGBoost classifier achieved the highest discriminative performance (AUC = 0.79, 95% CI 0.76-0.82), which did not differ significantly from multivariable logistic regression (AUC = 0.78, 95% CI 0.75-0.81). Across all algorithms, AUC ranged from 0.76 to 0.79, with specificity consistently high (0.79-0.83) and sensitivity moderate (0.54-0.64). At the 0.50 threshold, the tuned XGBoost classifier showed positive and negative predictive values of 0.70 and 0.75. Restricted to variables measured before age 40, the same classifier achieved an AUC of 0.74 (95% CI 0.71-0.78). Shapley analysis identified female sex, poor sleep quality, psychological distress, dietary trigger foods, lower household income, and reduced social support from friends as the dominant contributors to model output. CONCLUSION:ML models using life-course data can predict midlife headache with moderate-to-good discriminative ability. The prominence of modifiable psychosocial and socioeconomic predictors suggests concrete targets for future etiological and interventional research. Further model refinement, external validation, and assessment of clinical and public health utility are needed before real-world implementation. CLINICAL SIGNIFICANCE:Sleep quality, psychological distress, social support and household income, asked during routine dental history-taking, identify adults more likely to report headache; bruxism and dental attendance do not. Because sensitivity is moderate, these items should guide who warrants fuller headache and orofacial pain assessment rather than serve as a screening test.
OBJECTIVE:To quantify the degree of conversion (DC), shrinkage strain, shrinkage stress, and polymerization kinetics of ten commercial resin-based composites (RBCs). METHODS:Ten RBCs were tested. Four rapid-cure Tetric formulations (Tetric plus Fill, PowerFill, Tetric plus Flow, and PowerFlow) were photocured for 3 s at 3.0 W/cm² for DC and strain measurements and the corresponding stress specimens received 2.5 W/cm² for 3 s. Six comparator RBCs were photocured for 10 or 20 s at 1.2 W/cm² in accordance with their manufacturers' instructions. The DC was measured using ATR-FTIR on 0.2-mm-thick specimens for 720 s, whereas axial shrinkage strain and stress were recorded on 1.0-mm-thick specimens for 24 h. Because material and protocol were not varied independently, across-material comparisons were interpreted as intended-use comparisons rather than isolated formulation effects. RESULTS:Tetric plus Fill and Tetric PowerFill produced comparable DC and 24 h shrinkage strain and stress. Among the regular-viscosity RBCs, Admira Fusion x-tra produced the lowest 24 h strain and stress. Tetric PowerFlow produced lower 24 h strain and stress than Tetric plus Flow. The rapid-cure Tetric material/protocol combinations exhibited earlier and larger DC-, strain-, and stress-rate peaks. Estelite Flow had a lower maximum DC rate and a broad, lower strain-rate peak, but it achieved the highest DC at 720 s and had a smaller late-time strain slope. In a regression constrained through the origin, the 24 h shrinkage stress increased with 24 h shrinkage strain under the tensometer geometry and compliance used in this study. SIGNIFICANCE:The 24 h measurements show that low early shrinkage values may not predict the final material values and ranking.
OBJECTIVE:To compare dynamic and robotic computer-assisted implant surgery (d-CAIS and r-CAIS) in the placement of short implants in terms of implant placement accuracy and primary stability. MATERIALS AND METHODS:In this controlled in vitro study, Ø3.3- and Ø4.75-mm implants with a length of 4.5 mm were placed in standardized D3-density bone-analogue models using d-CAIS or r-CAIS (n = 9 per experimental condition). Coronal, apical, and angular deviations and implant stability quotient (ISQ) were analyzed using robust two-factor linear models; and maximum insertion torque using the Kruskal-Wallis test followed by Dunn pairwise comparisons. Pairwise comparisons were adjusted using the Bonferroni adjustment (α = 0.05). RESULTS:Implant diameter significantly affected coronal and apical deviations, with significant technique-by-diameter interactions for both outcomes. Within r-CAIS, neither coronal nor apical deviation differed significantly between diameters (both P = 1.000), whereas within d-CAIS, Ø4.75-mm implants showed significantly greater coronal (MD 0.508 mm; 95% CI: 0.200 to 0.816 mm; P < .001) and apical deviations (MD 0.412 mm; 95% CI: 0.063 to 0.761 mm; P = .014) than Ø3.3-mm implants. At Ø3.3 mm, r-CAIS also showed lower angular deviation than d-CAIS (MD -1.669°; 95% CI: -2.639° to -0.699°; P < .001). Maximum insertion torque did not differ significantly between techniques at either diameter, whereas overall ISQ was slightly lower with r-CAIS than with d-CAIS (MD -4.903; 95% CI: -6.930 to -2.875; P < .001). CONCLUSIONS:Under in vitro conditions, r-CAIS may provide more consistent placement accuracy across implant diameters than d-CAIS when placing short implants, although no significant overall differences in accuracy were detected between the two CAIS techniques. Maximum insertion torque did not differ significantly between techniques at either diameter, whereas d-CAIS yielded slightly higher overall ISQ values.
OBJECTIVES:To develop and evaluate a deep learning-based framework for predicting the final color of lithium disilicate ceramic veneers and to establish a target-driven screening algorithm for identifying and ranking candidate veneer-try-in paste combinations for various abutment-target shade scenarios. METHODS:Lithium disilicate veneer specimens were fabricated in 7 shades and 3 thicknesses. Try-in pastes from 2 commercial systems and 29 VITA Linearguide 3D-MASTER shade tabs were used to simulate cementation and abutment/target shades, respectively. Spectral reflectance data were captured and converted to CIELAB coordinates. A fully connected neural network (FCNN) incorporating batch normalization and ReLU activation was trained to predict the final CIELAB coordinates of layered veneer assemblies from 12 material-related colorimetric inputs. Prediction accuracy was assessed using CIEDE2000 color differences (ΔE00), referenced against the perceptibility threshold (PT = 0.8) and acceptability threshold (AT = 1.8). The trained model was applied to 841 abutment-target shade scenarios to screen 210 candidate veneer-try-in paste combinations per scenario. The screened candidate combinations were further evaluated using measured final-color data. RESULTS:In the test set, the FCNN achieved a mean ΔE00 of 0.50 ± 0.27, with 100% of the predictions falling below the AT and 87.50% below the PT. Clinically acceptable candidate combinations were identified in 267 scenarios, yielding 514 ranked candidate combinations. When evaluated using the measured final-color data, the mean ΔE00 was 0.55 ± 0.40 between measured and predicted colors, and 1.22 ± 0.51 between measured colors and target shades; 87.16% of the screened candidate combinations remained below the AT (ΔE00 < 1.8). CONCLUSIONS:The proposed FCNN-based framework accurately predicted veneer final color and enabled target-driven screening and ranking of candidate veneer-try-in paste combinations within the predefined material library. CLINICAL SIGNIFICANCE:This framework may provide a clinically relevant decision-support approach by narrowing and prioritizing candidate veneer-try-in paste combinations before chairside try-in, potentially reducing reliance on empirical trial and error during material selection.
Objectives This study evaluated the anticariogenic effect and antibacterial activity of a titanium tetrafluoride (TiF4)/chitosan (Ch) toothpaste on enamel and dentin demineralization in an in vitro microcosm biofilm model. Methods Microcosm biofilm was produced from human saliva mixed with McBain saliva (0.2% sucrose) on bovine enamel and dentin for three days (5% CO2, 37°C). The treatments were applied as slurry (1 × 60 s/day): 1) TiF4/Ch (1400 ppm F⁻, 0.5% chitosan, 75% deacetylation, 500 mPas, pH 4.5); 2) TiF4 (1400 ppm F-, pH 4.5); 3) Ch (0.5% chitosan, 75% deacetylation, 500 mPas, pH 4.5); 4) Elmex® Caries Protection (GABA, Switzerland, 1450 ppm F- as AmF, pH 4.5, positive control); 5) placebo (pH 7.0, negative control); and 6) phosphate-buffered saline (PBS, pH 7.2). Colony-forming units (CFU) count was performed for total microorganisms, Lactobacillus spp., and Streptococcus mutans/S. sobrinus. Demineralization was measured by transverse microradiography (TMR). Data were compared using Kruskal-Wallis/Dunn test (p < 0.05). Results In enamel biofilm, TiF4/Ch significantly reduced Streptococcus mutans/S. sobrinus compared to placebo, whereas in dentin biofilm, this effect was observed only for TiF4 alone compared to both placebo and PBS. In enamel, TiF₄/Ch showed the lowest values of the integrated mineral loss (ΔZ) and lesion depth (LD), differing from Chitosan, Placebo and PBS groups. In dentin, similar performance was found for TiF4 and Elmex® on ΔZ, but not on LD (Elmex® was similar to placebo). No performance difference was observed between TiF4 and TiF4/Ch under this model. Conclusions In conclusion, toothpastes containing TiF4 were able to reduce enamel and dentin demineralization in an in vitro microcosm biofilm model. Clinical Relevance TiF₄/Ch toothpaste reduced enamel and dentin demineralization under the present in vitro model, supporting its anticaries potential.
Objectives To evaluate the predictive accuracy of single-factor, multi-factor, and machine learning-based caries risk assessment (CRA) methods in predicting caries risk among children and adults, updating the 2015 review. Data The review was reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020, supplemented by relevant items adapted for prognostic accuracy reviews. Paired sensitivity and specificity data were extracted, and 2 × 2 contingency tables were reconstructed where necessary. Source PubMed, Web of Science, Cochrane Library, Embase, and Scopus were searched from February 2015 to July 2025. Study Selection Studies evaluating CRA methods with a minimum 1-year follow-up and sufficient data to reconstruct a 2 × 2 table were included. Of the 7,332 records identified, 30 studies met the inclusion criteria; 16 contributed to the meta-analysis. Results The full Cariogram in children demonstrated pooled sensitivity 72.10% and specificity 69.96%. Caries Management by Risk Assessment (CAMBRA) yielded a sensitivity of 67.65% and a specificity of 58.96% with substantial heterogeneity. The American Academy of Paediatric Dentistry (AAPD) CRA showed high sensitivity (95.56%) but very low specificity (5.12%), suggesting it may be more suitable for initial screening than for definitive risk stratification. Past caries experience demonstrated moderate predictive accuracy. Machine learning showed potential but lacked sufficient data for pooling. Conclusions CRA methods demonstrate moderate predictive accuracy, with substantial variability across populations, tools, and study designs. Clinical Significance CRA methods should be used alongside clinical judgement. Further prospective validation and incorporation of objective biomarkers may improve future caries risk prediction.
OBJECTIVES:To investigate Norwegian dentists' use of restorative materials and techniques for Class II restorations over a nine‑year period (2015-2024), following the national transition to non‑amalgam restorative dentistry. METHODS:A questionnaire survey was administered to dentists attending operative dentistry continuing‑education courses at 16 locations in Norway between 2015 and 2024. Participants recorded diagnostic information, restorative procedures and materials for Class II restorations during five working days. In total, 5056 restorations from 581 dentists were included. RESULTS:Resin-based composite was used in 94.4% of the restorations, with a strong preference for conventional composites over bulk‑fill versions. One‑third of the restorations involved multi‑material layering, most frequently with bulk‑fill flowable composites as base materials. The use of protective pulpal liners declined from 16% to 6% over time. Adoption of universal adhesives increased markedly from 10% in 2015 to 60% in 2024. Rubber dam isolation was used in 7% of the procedures, with most clinicians relying on cotton rolls or pads. CONCLUSIONS:Norwegian dentists have almost entirely transitioned to conventional composite materials for Class II restorations, with growing adoption of multi-material layering and universal adhesives. Use of pulpal liners declined substantially over the study period. CLINICAL SIGNIFICANCE:These findings provide a comprehensive overview of national restorative practices and highlight key trends relevant for clinical training, guideline preparation, and future research and development of restorative materials and techniques.
OBJECTIVE:To describe a technical proof-of-concept workflow using a patient-specific digital index as a physical intraoperative reference for positioning a porcine acellular dermal matrix and limited peripheral application of an n-butyl-2-cyanoacrylate-methacryloxy sulfolane surgical adhesive (Glubran 2; GEM Srl, Viareggio, Italy) to maintain the clinically selected matrix position during root coverage surgery. MATERIALS AND METHODS:Standardized photographs and an intraoral scan were used for virtual planning. A tooth-supported matrix-positioning index was designed and fabricated by vat photopolymerization and used as a physical reference for extraoral matrix trimming and intraoperative positioning. The fully hydrated matrix was adapted within the indexed boundaries and stabilized with discrete peripheral adhesive microdroplets while the central matrix-to-bed interface was kept free of adhesive. RESULTS:The index seated passively and provided a physical reference for the planned matrix boundaries. The matrix remained clinically stable during index removal, flap advancement, and suturing. Baseline and 1-year clinical measurements are reported for descriptive context; no quantitative index-transfer accuracy assessment was performed. CONCLUSIONS:This single-patient technical proof of concept showed that a patient-specific index could be used as an intraoperative reference for matrix positioning, with limited peripheral cyanoacrylate stabilization before flap closure. CLINICAL SIGNIFICANCE:A patient-specific index may provide a physical reference for planned matrix positioning, while limited peripheral cyanoacrylate may help maintain matrix stability before flap closure.
BACKGROUND:Early childhood caries (ECC) is preventable, and household secondhand smoke (HSHS) is a modifiable risk factor. However, evidence regarding critical early-life exposure windows and potential sex differences in the association remains limited. OBJECTIVE:To examine the associations between HSHS exposure from early fetal life to 24 months of age and ECC in preschool children, and to explore potential sex differences. METHODS:Data from 2,431 mother-child pairs in the Shanghai Maternal-Child Pairs Cohort were analyzed. HSHS exposure was self-reported during early and late pregnancy and at 2, 6, and 24 months of age. ECC was clinically diagnosed at 3-5 years of age. Group-based trajectory modeling identified HSHS exposure patterns, and Cox proportional hazards models estimated associations between HSHS exposure and ECC. RESULTS:Three distinct HSHS exposure trajectories were identified: Never Exposure (31.8%), Prenatal Decline-Postnatal Rebound (40.5%), and Persistently High Exposure (27.7%). Children in the latter two trajectories had a higher risk of ECC compared with those in the Never Exposure group (adjusted HR=1.23, 95% CI: 1.01-1.49; and adjusted HR=1.36, 95% CI: 1.12-1.66, respectively). Exposure at all assessed time points was associated with increased ECC risk, with the strongest associations observed during early pregnancy and at 24 months. Sex-stratified analyses showed significant associations among girls but not among boys. CONCLUSION:Early-life household secondhand smoke exposure was associated with an increased risk of early childhood caries in the overall study population, with significant associations observed among girls but not boys in sex-stratified analyses. CLINICAL SIGNIFICANCE:Assessment of household secondhand smoke exposure during early life may provide useful information for caries risk assessment and oral health counseling in preschool children.
OBJECTIVE:To develop a mixed reality (MR)-assisted, guide-free workflow for patient-specific implant (PSI)-based maxillary fixation and evaluate its positioning equivalence and procedural efficiency relative to conventional guide-assisted PSI fixation. METHODS:In this non-randomized cohort study, 28 patients undergoing Le Fort I osteotomy independently selected their preferred workflow after receiving detailed information on both approaches and were categorized according to the workflow received. MR navigation guided osteotomy lines and screw-hole positioning in the MR-assisted group, whereas conventional surgical guides were used in the guide-assisted group. Equivalence was assessed using two one-sided tests (TOST), with margins of ±0.5 mm for translational and ±1.0° for rotational outcomes. RESULTS:All 90% confidence intervals (CIs) for between-group differences in translational and rotational positioning errors were entirely within the prespecified equivalence margins, supporting statistical equivalence within these bounds. Small directional offsets were observed for A-X (mean difference, -0.206 mm), UL6-Y (0.168 mm; 90% CI, 0.070-0.267 mm), and yaw (0.159°; 90% CI, 0.017-0.302°), although all remained within the equivalence margins. Preoperative preparation time and mean Le Fort I segment time were reduced in the MR-assisted group, which also required fewer intraoperative adjustments (2.29 ± 1.49 vs. 4.29 ± 1.20; P = 0.0006). CONCLUSION:MR-assisted, guide-free PSI fixation showed positioning outcomes statistically equivalent to guide-assisted fixation within the prespecified margins and was associated with greater procedural efficiency. CLINICAL RELEVANCE:MR-assisted, guide-free PSI fixation may reduce reliance on surgical guides while maintaining between-workflow positioning differences within prespecified equivalence bounds.
Objectives To evaluate the three-dimensional bone regeneration achieved with digitally customized titanium meshes in patients presenting Cawood and Howell Class V defects, 8 months after surgery. Methods This retrospective clinical case series included 9 patients with severe alveolar ridge atrophy (Cawood and Howell Class V), who underwent guided bone regeneration using customized titanium meshes at 10 surgical sites (8 mandibular and 2 maxillary). Meshes were designed through a fully digital workflow based on cone-beam computed tomography (CBCT) data and manufactured using Direct Metal Laser Sintering (DMLS). This approach allowed accurate preoperative planning, optimal adaptation of the mesh, smooth and rounded margins, intrinsic stability, and reduced intraoperative time. Surgical procedures were performed with careful flap management to achieve tension-free primary closure. Clinical and histological outcomes were assessed at 8 months postoperatively. Results No cases of mesh exposure, infection, or graft failure were observed. The mean vertical bone gain was 5.18 ± 1.82 mm, while the mean horizontal bone gain was 7.27 ± 1.74 mm. The mean regenerated bone volume was 1.25 ± 0.67 cm³. Histological analysis revealed vital, well-vascularized bone in direct contact with residual graft material. Conclusions Within the limitations of this retrospective case series, customized titanium meshes were associated with measurable three-dimensional bone gain in Cawood and Howell Class V defects. These preliminary findings support the feasibility of this patient-specific digital approach and warrant further investigation in larger prospective studies with appropriate control groups.
OBJECTIVE:To investigate the oral health status, oral health-related behaviours (OHB), and oral microbiota between preschool children and their parents. METHODS:This cross-sectional study recruited 294 families. The caries and oral hygiene status of children and parents were assessed by calibrated dentists. Plaque samples collected from children with severe early childhood caries and their parents were analysed using 16S rRNA sequencing. OHB was collected via questionnaires. Bivariate analysis, Principal Coordinates Analysis, Binary Logistic Regression, and Spearman's rank correlation were performed. RESULTS:Children's caries status was correlated with fathers' (rs=0.30, 95%CI:0.10-0.47, p=0.002, n=103 pairs) and mothers' caries status (rs=0.29, 95% CI:0.16-0.41, p< 0.001, n=215 pairs). Higher odds of caries were observed among children whose fathers (OR = 4.67, 95%CI:1.74-12.49, p = 0.002) or mothers (OR = 2.63, 95% CI:1.30-5.33, p = 0.007) had caries. The proportion of children who established favourable OHB was higher among children whose fathers (p=0.002) or mothers (p<0.001) had favourable OHB. Children's toothbrushing duration was correlated with fathers (rs =0.58,95% CI: 0.41-0.72, p<0.001, n=78 pairs) and mothers (rs=0.55,95% CI: 0.45-0.64, p<0.001, n=207 pairs), while snacking frequency was solely correlated with mothers (rs=0.45,95%CI:0.33-0.56, p<0.001). Likewise, the relative abundance of Porphyromonas gingivalis (rs = 0.45, 95% CI: 0.16-0.68, adjusted p = 0.009) and Streptococcus sobrinus (rs = 0.42, 95% CI: 0.12-0.65, adjusted p = 0.021) were correlated only in child-mother pairs. CONCLUSION:Children's caries status, OHB, and oral microbiota were associated with those of their parents. Exploring family-centered health promotion strategies is recommended. CLINICAL SIGNIFICANCE:Children's caries status, establishment of favourable oral health-related behaviours, and oral microbial profiles were associated with those of their parents, particularly mothers. Early childhood caries management should focus not only on the child but also on parents. Enhancing parental engagement and family cohesion may contribute to better child health outcomes.
OBJECTIVES:Oral submucous fibrosis (OSF) is a chronic and progressive potentially malignant disorder with an increased risk of transformation to oral squamous cell carcinoma (OSCC). Some histopathological features of OSF may complicate adequate recognition of malignancy in OSF. This study aimed to develop a lightweight deep learning framework for classifying OSF-associated OSCC from OSF using whole-slide images (WSIs). METHODS:This retrospective study involved hematoxylin and eosin (H&E)-stained WSIs from 156 OSF and 94 OSF-OSCC, treated at the National Dental Hospital, Colombo, Sri Lanka. Data were allocated into training and test datasets according to an 80:20 split. A total of 4,966,521 image patches extracted from 200 WSIs were used to train and cross-validate a hybrid-operator multiple instance learning (MIL) model for classifying OSF and OSF-OSCC. The model was then tested preliminarily using 50 WSIs (20% unseen images) and 20 external photomicrographs. Discrimination, calibration, and net benefit of the model were evaluated. RESULTS:The framework achieved an AUC of 0.986 (95% CI: 0.953-1.000), an AUPRC of 0.977 (95% CI: 0.935-1.000), and a Brier score of 0.034 (95% CI: 0-0.084) on the internal test WSIs. Moreover, 19 out of the 20 external photomicrographs for preliminary external testing were correctly classified by the framework. On both datasets, The recall, specificity, precision, balanced accuracy, and negative predictive value of the MIL model in classifying OSF-OSCC and OSF were 100% (95% CI: 83.2-100%), 92% (95% CI: 80.8-97.8%), 83.3% (95% CI: 62.6-95.3%), 96% (95% CI: 82-98.9%), and 100% (95% CI: 92.3-100%) respectively. Additionally, the model had potential net benefit at all evaluated probability thresholds for classifying OSF and OSF-OSCC. CONCLUSION:A lightweight deep learning model demonstrated satisfactory performance in classifying OSF-associated OSCC and OSF at internal testing and preliminary external photomicrograph testing. CLINICAL SIGNIFICANCE:The deep learning model may serve as a diagnosis decision-support tool for classifying OSF and OSF-associated OSCC. The model may help flag suspicious cases for pathologist review following external WSI and prospective multicenter validation.
Objectives To evaluate the effect of intraarch connector design and build angle on the fabrication trueness and precision, and overall accuracy, of additively manufactured (AM) compared to subtractively manufactured (SM) frameworks in high-impact polymer composite (HIPC) for complete-arch implant-supported prostheses on four implants. Materials and Methods A typodont model with four implants and their multiunit abutments were digitized and an implant-supported complete-arch framework was designed. Three design files (no bar, horizontal bar, Y-shaped bar) were used to fabricate AM specimens using a glass-filler-reinforced composite resin in three different build angles (0°, 45°, 90°) (n=10). Ten SM frameworks fabricated from HIPC served as the control group. All frameworks were digitized and superimposed. Trueness and precision were evaluated in separate regions, as well as linear abutment and interimplant distance deviations. Marginal gaps were evaluated after seating the frameworks with one screw inserted in left posterior abutment. Data were statistically analyzed (α = 0.05) Results Both build angle and intraarch connector design significantly affected trueness, precision, linear deviations, and marginal gaps. Compared to the control group, test groups mostly showed similar or lower accuracy. No clear pattern among other test groups was observed. Marginal gaps differed significantly among groups (p<0.05), ranging from 50.2 µm at the right posterior abutment in the 0°-no-bar group to 573.7 µm at the left anterior abutment in the 90°-horizontal-bar group. 0° no-bar mostly showed the lowest surface deviation, lowest linear deviation, and least marginal gaps (p<0.05). Conclusions Within the limitations of this single-system in vitro study, AM complete-arch implant-supported interim fixed prostheses in a 0° no-bar configuration demonstrated accuracy comparable to SM HIPC. The marginal gaps found in some groups were beyond clinical acceptability. Printing such prostheses in 45° and 90° configurations using the tested printer, resin, and post-processing combination cannot be recommended. Clinical Significance The differences in marginal gaps found between the groups showed magnitudes beyond clinical acceptability and therefore additive manufacturing of complete-arch implant-supported interim fixed prostheses using build angles other than 0°and/or incorporating intraarch connectors should be approached with caution.
BACKGROUND:The association between sustained anterior head flexion during portable electronic device use and neuromuscular function remain poorly understood. This study aimed to investigate the relationship between TMD status, the HT operational classification, and the surface electromyographic activity of the masticatory muscles. METHODS:This cross-sectional study included 100 adults (63 F, 37 M; mean age 32.4 ± 11.3 years), equally distributed into four groups according to TMD status and HT classification. HT operational classification was defined by portable electronic device-use duration and an illustrated postural scale. Surface electromyography was recorded during clenching in the neutral head position and during 40°-60° anterior head flexion. POC TA, POC MM, Asymmetry Index, Activity Index, Torque Index, and Impact were analyzed. Main effects and interactions were assessed using Scheirer-Ray-Hare tests, and within-group changes using paired Wilcoxon tests. Statistical significance was set at p < 0.05. Multiple related comparisons were adjusted using the Benjamini-Hochberg false discovery rate procedure (FDR). RESULTS:TMD status was significantly associated with POC TA, POC MM, Asymmetry Index, and Torque Index in both positions (all pFDR ≤ 0.027). HT operational classification was significantly associated with Activity Index in both conditions (both pFDR < 0.001). Activity Index decreased during flexion in all groups (all pFDR ≤ 0.041), but the magnitude of change did not differ by TMD status, HT operational classification, or their interaction (all p ≥ 0.205). CONCLUSIONS:TMD status and HT operational classification showed distinct associations with the investigated sEMG parameters. Participants with TMD exhibited lower muscular symmetry and greater imbalance, whereas HT operational classification was associated primarily with differences in temporalis-masseter recruitment. Activity Index emerged as a potentially posture-sensitive parameter. However, TMD-related findings should be interpreted cautiously because the analyses were not adjusted for demographic differences. CLINICAL RELEVANCE:Activity Index may represent a potentially posture-sensitive sEMG parameter reflecting posture-associated differences in neuromuscular function; however, its clinical, diagnostic, and prognostic relevance remains to be established.
OBJECTIVES:To evaluate the influence of thickness and build orientation on the optical properties and relative translucency of an additively manufactured 3Y-TZP zirconia system and to compare its optical behavior with that of a subtractively manufactured 3Y-TZP zirconia system. MATERIALS AND METHODS:Zirconia discs were fabricated at five thicknesses (0.25-2.00 mm) and allocated to three groups: additively manufactured at 0º (AM0º), additively manufactured at 90º (AM90º), and subtractively manufactured (SM) (n = 9). Spectral reflectance was measured over white and black backgrounds. Kubelka-Munk scattering (S) and absorption (K), transmittance (T%), light reflectivity (RI), infinite optical thickness (χ∞), and albedo coefficient (a) were calculated. Relative translucency (RTP00) and translucency differences were determined according to translucency perceptibility and acceptability thresholds. RESULTS:Scattering was the dominant optical property governing light extinction in all groups (0.978 < a < 0.999). Scattering and absorption increased, whereas transmittance decreased, with increasing specimen thickness. The SM zirconia system showed lower scattering and higher transmittance than the AM zirconia system. RTP00 values were higher for SM zirconia than for AM 3Y-TZP zirconia at equivalent thicknesses. Translucency differences between SM and AM groups exceeded the translucency acceptability threshold, whereas differences between AM0º and AM90º remained below the perceptibility threshold. CONCLUSIONS:The additively manufactured 3Y-TZP zirconia system exhibited higher scattering and lower translucency than the subtractively manufactured 3Y-TZP zirconia system, whereas differences in translucency between build orientations remained below the perceptibility threshold. CLINICAL RELEVANCE:The additively manufactured 3Y-TZP zirconia system exhibited lower translucency than the subtractively manufactured 3Y-TZP zirconia system at equivalent thicknesses. These findings may be considered when selecting between the evaluated zirconia systems for esthetically demanding restorative situations.
OBJECTIVES:This meta-analysis compared hydraulic calcium silicate-based (HCSS) versus other types of root canal sealers regarding postoperative pain and treatment outcomes. DATA AND SOURCES:Five electronic databases were searched for randomized and non-randomized clinical studies from 1947 to 2026. Post-operative pain assessment was extracted as visual analogue scale scores (0-10). Treatment success and failure were recorded according to prespecified loose and strict radiographic criteria. For continuous and dichotomous outcomes, pooled effect estimates (e.g. standardized mean differences (SMD), odds ratios (OR)) with 95% confidence intervals (95%CI) were calculated using fixed- or random-effects models. STUDY SELECTION/RESULTS:Fifty-five articles were included, reporting on 53 cohorts comprising 5913 teeth at the end of the observation period. Forty studies investigated postoperative pain; 21 assessed treatment outcome using loose criteria and 14 strict criteria, with both reported in 12 studies. Sealer extrusion or resorption was documented for 25 cohorts. Patients treated with HCSS reported slightly lower postoperative pain scores after 6 hours (OR=-0.27, 95%CI:-0.51--0.04, moderate level of evidence), although this tendency was inconsistent over different postoperative intervals. For treatment success defined according to loose criteria, use of HCSS resulted in significantly fewer failures than other types of sealers (OR=0.70, 95%CI:0.50-0.99,high level of evidence), whereas no significant difference between sealer types was observed when strict criteria were applied (OR=0.89, 95%CI:0.67-1.19, high level of evidence). CONCLUSION:HCSS represent a clinically validated sealer group with no increased risk of elevated postoperative pain and can contribute to successful root canal treatment, with success rates comparable to those of other types of sealers. CLINICAL SIGNIFICANCE:Hydraulic calcium silicate-based root canal sealers were promoted for their biocompatibility and bioactivity. The results of clinical trials show that HCSS perform similar to other types of root canal sealers in terms of postoperative pain and treatment outcomes and display a well-investigated alternative to epoxy resin or zinc oxide eugenol sealers. REGISTRATION:PROSPERO database CRD420261365434.
Background Conventional caries indices, such as Decayed, Missing, and Filled Teeth (DMFT) and Decayed, Missing, and Filled Surfaces (DMFS), remain widely used. However, they do not adequately distinguish between lesion severity, restoration extent, and caries-related tooth loss, nor do they account for differences in the available tooth surfaces. This study aimed to develop a Severity-Adjusted Caries Index (SACI), an age-stratified and surface-normalized composite index designed as a structurally differentiated refinement of conventional cumulative caries-burden measures, and to evaluate its external known-groups validity. Methods This two-phase methodological cross-sectional study included a derivation cohort of 223 adults and an independent external validation cohort of 200 adults, including 100 participants with type 1 diabetes mellitus (T1D) and 100 controls without diabetes. The SACI integrates ICDAS-based caries lesion severity, restoration extent, and caries-related tooth loss within a surface-normalized framework. Age-specific weights were derived separately for participants aged <35 and ≥35 years using a deterministic exact constrained search against a composite optimization target incorporating CAMBRA-derived burden measures and conventional caries indices. External known-groups validation assessed the discriminatory performance against T1D status using ROC analysis, logistic regression, and pairwise DeLong comparisons. Results The SACI showed clear age-specific weighting patterns. In the derivation phase, the final age-specific models showed moderate correlations with the composite target (Pearson r=0.641 for <35 years and 0.638 for ≥35 years). Nested 5-fold cross-validation of the complete weight-selection procedure yielded pooled out-of-fold R² values of 0.345 and 0.315, respectively. In the validation cohort, SACI was significantly higher in participants with T1D than in controls (p<0.001) and showed the highest discriminatory performance among the evaluated indices (AUC=0.671), compared with DMFT (AUC=0.606) and DMFS (AUC=0.572). Conclusions SACI provided a more structurally differentiated and age-sensitive representation of cumulative caries burden than conventional unweighted indices and showed greater discrimination of T1D status in an independent adult cohort. These findings support SACI as a potential refinement of conventional caries-burden assessment rather than as a wholly distinct construct. Further validation against direct caries-related outcomes and in broader populations is warranted. Clinical Significance Conventional caries indices may not fully reflect the structural complexity of caries experience in adults because they treat lesions, restorations, and tooth loss as equivalent components. SACI provides a severity-weighted, age-sensitive, and surface-normalized refinement of cumulative caries-burden assessment by incorporating lesion severity, restoration extent, and caries-related tooth loss. It is intended to complement and refine, rather than replace, conventional indices such as DMFT and DMFS.
