Peri-prosthetic soft tissues play a critical role in maintaining biologic stability, functional longevity, and esthetic outcomes of restorative and implant therapy. Rather than acting as passive barriers, these tissues function as dynamic biologic interfaces that respond to restorative procedures, prosthetic contours, and mechanical influences. Contemporary understanding has expanded the traditional concept of gingival biotype into the broader periodontal and peri-implant phenotype, encompassing soft tissue thickness, keratinized mucosa width, and supracrestal tissue dimensions. To ensure a comprehensive overview of the literature, a focused electronic search was conducted across the PubMed, Scopus, and Cochrane Central Register of Controlled Trials databases for articles published between January 2000 and March 2026. Search strings utilized combinations of Medical Subject Heading (MeSH) terms and free-text terms including “peri-prosthetic soft tissue,” “peri-implant phenotype,” “emergence profile,” and “supracrestal tissue attachment”. Selection prioritized randomized controlled trials, prospective clinical studies, and high-quality systematic reviews published in English. Additionally, classic historical landmark papers establishing foundational biological concepts were manually retrieved and included to provide necessary context. Evidence indicates that soft tissue phenotype significantly influences marginal tissue stability, recession susceptibility, and peri-implant bone remodeling. Prosthetic design variables, including emergence profile, restoration contour, margin placement, and cementation techniques, play a decisive role in maintaining peri-prosthetic tissue health. Adequate soft tissue thickness and keratinized mucosa are associated with improved biologic stability, although some aspects remain subjects of ongoing debate. Recent advances in soft tissue augmentation, biomaterials, digital workflows, and minimally invasive approaches have expanded opportunities for phenotype modification and tissue optimization. Successful peri-prosthetic tissue management requires integration of periodontal biology, prosthetic design principles, and phenotype-driven treatment planning. Contemporary strategies focused on biologic preservation, soft tissue optimization, and minimally traumatic restorative protocols contribute to long-term peri-prosthetic health, stability, and esthetic success.
To evaluate the association between smile arc curvature, skeletal pattern, and maxillary incisor display among orthodontic patients attending King Khalid University College of Dentistry. This retrospective cross-sectional analytical study included 150 eligible orthodontic patients. Standardized pretreatment posed smile photographs and lateral cephalometric radiographs were analyzed. Smile arc curvature was classified as consonant, flat, or reverse. Associations with sagittal skeletal pattern (ANB), vertical skeletal pattern (SN–MP), and maxillary incisor display were evaluated using Pearson’s chi-square or Fisher’s exact test. Multinomial and binary logistic regression analyses were performed to explore adjusted associations. Consonant smile arc was the most prevalent pattern (63.3
This study evaluates the reliability and participants’ responses to a contactless artificial intelligence (AI) device powered by Remote Photoplethysmography (rPPG) technology for screening vital signs. The contactless AI-based device was compared with automated devices and the manual method as part of its validation for potential healthcare screening applications in dental clinics. A survey was conducted to assess the participants’ perception. The Bland–Altman analysis was performed to assess agreement between methods. A total of 499 patients were recruited for this study. There were no significant differences between the contactless AI-based device system and automated or manual measurements for respiratory rate and oxygen saturation (p > 0.05). Significant differences were observed in heart rate, and systolic and diastolic blood pressure compared with the automated device (p < 0.05). Bland-Altman analysis revealed wide limits of agreement for blood pressure (± 30 mmHg for SBP, ± 20 mmHg for DBP) with proportional bias, indicating that BP measurement requires substantial algorithmic refinement before clinical implementation. Respiratory rate and oxygen saturation demonstrated excellent agreement with reference methods. Participants demonstrated high acceptance and positive perceptions of the AI-based system (all mean scores > 4.0) on a 5-point Likert scale. Participants also perceived that people and patients were generally optimistic about the potential of a contactless AI-based device used in dentistry. This study demonstrates that contactless rPPG technology shows validated clinical accuracy for respiratory rate and oxygen saturation monitoring in dental settings. However, blood pressure measurement algorithms require substantial refinement and further validation before clinical deployment. (250 words)
Abstract Artificial intelligence (AI) is transforming healthcare delivery globally, with increasing applications in public health dentistry. This scoping review maps and synthesises the current state of AI integration in public health dentistry practice, education, research, and surveillance. A comprehensive literature search was conducted across PubMed, Scopus, Web of Science, Embase, and the Cochrane Library (with Google Scholar used as a supplementary source) from database inception to December 31, 2024. Thirteen studies were included to map the range of evidence on AI applications, performance metrics, and implementation challenges using PRISMA-ScR guidelines and a structured narrative synthesis. Consistent with scoping review methodology, this study aimed to map existing evidence and identify research gaps rather than evaluate or establish the effectiveness of AI interventions. In preliminary studies conducted under varied and predominantly controlled or pilot conditions, AI applications were reported across multiple public health dentistry domains: (1) disease surveillance, with reported machine learning accuracy of 82–94% for caries prediction in individual studies; (2) community screening, with reported sensitivity of 85–92%; (3) health education, with reported 18–23% improvements in knowledge scores; (4) tele-dentistry, with reported diagnostic concordance of 81–87%; and (5) policy planning, with reported utilisation prediction accuracy of 76–82%. These figures are derived from heterogeneous, predominantly pilot studies and should not be interpreted as indicators of real-world effectiveness. Major implementation challenges included data quality issues (9/13 studies, 69%), algorithmic bias concerns (8/13, 62%), privacy and security barriers (7/13, 54%), and AI literacy gaps (10/13, 77%). Included studies suggest that AI may support several functions within public health dentistry; however, these conclusions are drawn from a small and heterogeneous evidence base dominated by pilot studies and narrative reviews, limiting generalisability to routine public health dental settings. Successful implementation will require addressing data quality, algorithmic transparency, workforce training, and ethical considerations.
Using finite element analysis, the present work examined the three-dimensional biomechanical responses of anterior and posterior teeth to a range of intrusion-to-retraction ratios during anterior space closure with clear aligners after extraction of a maxillary first premolar. A three-dimensional model of a maxillary first premolar extraction case was built, comprising the upper dentition, periodontal ligament, aligner, and attachments. The intrusion-to-retraction ratio was altered in a stepwise manner to define seven groups (C0–R6), and movement was reproduced through an iterative simulation of alveolar bone remodeling. For anterior and posterior teeth alike, three-dimensional displacement, change in tooth angulation, and the torque-loss-per-posterior-displacement (TL/PD) ratio were quantified. As the ratio rose, anterior crown displacement generally shifted from extrusion toward intrusion. Compared with C0, the 1:1 intrusion-to-retraction ratio reduced crown extrusion by 59.5
Post-2022 increase of large language models (LLMs) in dental education has generated a expansive heterogeneous literature spanning MCQ benchmarking, OSCE support, curriculum mapping. Despite significant increase, there is no evidence map showing where knowledge is robust or where methodological investment is needed. The function of retrieval-augmented generation (RAG) and knowledge graphs (KGs) in minimizing hallucinations is unexplored. The DentalEdu-AI Graph was created from 667 records: PubMed (549), Scopus (20), and web sources (98). After screening, 447 studies were chosen. Multi-label extraction identified AI type, dental specialty, assessment format, study design, and four quality flags was identified. A 37-node/49-edge knowledge graph of the dental AI ecosystem was constructed and validated with TF-IDF RAG-lite retrieval across 10 curriculum queries. Publication output risen considerably from 2 in 2022 to 203 in 2025 (+ 10,050
Accurate three-dimensional (3D) reproduction of facial soft-tissue geometry is a prerequisite for planning and fabricating maxillofacial epitheses. This single-subject pilot study compared the surface agreement of seven 3D facial scanning configurations available on the Ukrainian market against a cone-beam computed tomography (CBCT)-derived reference surface, reporting trueness-related surface-deviation metrics and acquisition time. Because only one participant was examined and no repeated acquisitions were obtained, the work is exploratory and does not establish device precision (repeatability) or population-level accuracy. A prospective comparative pilot acquisition was performed on one healthy adult volunteer at rest on a single day. Three radiopaque fiducial markers were placed over low-mobility sites (glabella, both temporal regions). A CBCT volume (Planmeca ProMax 3D Mid) was segmented in 3D Slicer (v5.10.0) to yield the reference soft-tissue surface. Seven configurations were assessed: Shining 3D MetiSmile, Creality CR-Scan Raptor Pro, Revopoint Miraco Pro, RAYFace Facial Scanner, Planmeca ProMax 3D ProFace, and Qlone Dental App (iPad and iPhone). In CloudCompare (v2.14.alpha), fiducial-based Point-Pairs registration was followed by Iterative Closest Point (ICP) alignment, and cloud-to-mesh (C2M) surface-deviation distances were computed. Only descriptive statistics were used. Across the evaluated low-mobility region, the structured-light devices showed sub-millimetre surface deviation, with Shining 3D MetiSmile and Creality CR-Scan Raptor Pro showing the smallest dispersion (RMSE 0.288 and 0.328 mm). RAYFace recorded the highest proportion of points within ≤ 2 mm (98.74
The greater palatine foramen (GPF) is a critical anatomical landmark for palatal nerve block anesthesia, periodontal surgery, and soft tissue graft harvesting. Population-specific morphometric data are needed for safe clinical practice. However, standardized CBCT-based GPF morphometric data with reliability analysis are lacking for the Saudi population. This retrospective cross-sectional study evaluated 68 CBCT scans of adult Saudi patients (18–65 years) from King Saud Dental University Hospital. Three primary variables were measured using Planmeca Romexis software: the distance from the GPF to the midline maxillary suture (GPF-MMS), the anteroposterior (AP) diameter, and the lateromedial (LM) diameter. Data were analyzed using R (version 4.5.3). Descriptive statistics, normality testing, and sex-based comparisons were performed. The mean GPF-MMS distance was 15.25 ± 1.26 mm (95
Psychological factors such as anxiety and stress frequently affect orthodontic treatment outcomes, but the underlying mechanisms remain unclear. To review evidence on how psychological factors influence orthodontic outcomes and to describe the biological pathways involved. We conducted a narrative review of Web of Science and PubMed up to January 2025, including 102 peer-reviewed studies on orthodontics, psychology, oral microbiota, taste, and inflammatory markers. Psychological factors affect orthodontic treatment through three pathways: First, nervous system activation (HPA axis and autonomic nervous system); Second, alterations in oral microbiota and salivary biomarkers (cortisol, α-amylase, s-IgA), and third, modulation of alveolar bone remodeling via pro-inflammatory cytokines (IL-1β, IL-6, IL-8). Taste changes under stress may indirectly alter dietary habits and oral microbial ecology. Most evidence is cross-sectional, limiting causal inference. Psychological factors significantly influence orthodontic outcomes via measurable biological mechanisms. Routine psychological assessment and patient education should be integrated into orthodontic practice
The study aimed to assess and compare the periodontal status, salivary thiocyanate levels and salivary pH among non-tobacco users, smoked tobacco users and smokeless tobacco users. A cross-sectional investigation was carried out on 75 construction workers from active construction sites in Mangalore, Karnataka, India, aged 20–60 years. Participants were categorized into three groups: individuals with no tobacco habit, those consuming smoked tobacco, and those using smokeless tobacco. The periodontal condition of all subjects was evaluated with the WHO Oral Health Assessment Form (2013). Salivary thiocyanate concentration was estimated with an ultraviolet spectrophotometer set at a wavelength of 447 nm, whereas salivary pH was measured using a digital pH meter. Data analysis was performed using the Statistical Package for Social Sciences (SPSS, version 19.0). To compare variations among the groups, one-way analysis of variance (ANOVA) was applied, followed by Tukey’s post hoc test for pairwise comparisons. Gingival bleeding scores were elevated in smokeless tobacco users (100
This study aimed to analyze global scientific trends in digital behavior management strategies in pediatric dentistry between 2000 and 2025. A bibliometric analysis was conducted using the Web of Science Core Collection, including English-language articles and reviews published between 2000 and 2025. Performance indicators, collaboration networks, Bradford’s Law, Lotka’s Law, keyword co-occurrence, and thematic mapping were evaluated using Bibliometrix and VOSviewer. A total of 150 publications were identified, with scientific output increasing markedly after 2018. Audiovisual distraction, anxiety, and pain emerged as central themes, while virtual reality was identified as a motor theme with high centrality and density. India, the United States, and Saudi Arabia were the most productive countries. Research output was concentrated in leading pediatric dentistry journals, and author productivity suggested a fragmented but growing field. Overall, digital behavior management research has expanded substantially, with immersive technologies such as virtual reality becoming increasingly prominent. Future multicenter collaborations and standardized outcome measures may facilitate clinical translation.
The gag reflex is a common challenge during dental procedures, often impairing clinical performance and causing patient discomfort. While pharmacological interventions are commonly employed, they can lead to adverse effects or be poorly tolerated. Herbal alternatives with local mucosal activity have gained increasing attention as potentially safer adjuncts. Quercus persica (Persian oak), rich in tannins, exhibits astringent and mucosal-desensitizing properties that may contribute to reducing gag reflex sensitivity. To evaluate the efficacy of a Quercus persica extract lozenge in reducing gag reflex severity in adult dental patients. In this randomized, double-blind, placebo-controlled clinical trial, 80 adult patients with a documented history of gag reflex were enrolled and equally allocated (1:1) into intervention and placebo groups (n = 40 each). Participants received either a 1-gram lozenge containing 200 mg of Quercus persica extract or an identical placebo. Gag reflex severity was assessed before and after intervention using a standardized 4-point ordinal scale across five intraoral regions. The primary outcome was the change in overall gag reflex score. Baseline demographic characteristics were comparable between the two groups. The Quercus persica group exhibited a significant reduction in overall gag reflex score (from 5.98 ± 2.26 to 1.38 ± 1.72; p = 0.001), in the placebo group (from 5.83 ± 2.01 to 5.10 ± 2.10; p = 0.002). Between-group comparison confirmed a significantly greater reduction in the intervention group (p < 0.001). Region-specific analysis revealed the greatest improvements in the soft palate and tonsillar regions, with mean reductions of 1.75 and 1.73 points, respectively (p < 0.001). Quercus persica lozenges were associated with a statistically significant reduction in gag reflex severity compared to placebo, particularly in highly sensitive intraoral regions. These findings suggest that Quercus persica may serve as a potential adjunctive approach for gag reflex management; however, conclusions should be interpreted with caution given the short-term assessment, and further studies are required to evaluate long-term efficacy, safety, and patient-reported outcomes.
Oral cancer, particularly oral squamous cell carcinoma, represents a major global health challenge with high rates of morbidity and mortality. Current treatments often encounter limitations such as toxicity and drug resistance. Curcumin, a natural polyphenol derived from turmeric, has shown significant promise as a therapeutic agent due to its anti-inflammatory, antioxidant, and broad-spectrum anticancer activities. However, its clinical application has been limited by poor solubility, rapid metabolism, and low bioavailability. This review examines the potential of novel curcumin formulations developed to address these challenges in oral cancer treatment. It explores advanced delivery systems including nanoparticle-based carriers, liposomes, niosomes, and hybrid technologies that enhance bioavailability and enable targeted delivery. Additionally, the review discusses synthetic curcumin analogues that offer improved stability and potency. These innovative approaches demonstrate enhanced anticancer effects through pro-apoptotic, anti-proliferative, and anti-angiogenic mechanisms, often exhibiting synergistic activity with conventional therapies. This review aims to synthesize current evidence on the mechanisms and efficacy of these advanced curcumin-based strategies and provide future perspectives on their role as safe and effective options in oral oncology.
Optimal wound healing is crucial in oral surgery, particularly in compromised conditions. Diabetes mellitus is associated with impaired wound healing due to reduced vascularization, immune dysfunction, and altered collagen deposition. Propolis, a bioactive resin produced by honeybees, has demonstrated antimicrobial, anti-inflammatory, and pro-healing properties. This study aimed to evaluate the impact of propolis-silver nanoparticles (AgNPs) coated sutures on early wound healing in the oral mucosa of healthy and diabetic rats through histological assessments. Propolis-silver nanoparticles (AgNPs) were synthesized and examined using FTIR. The propolis-AgNPs then used to coat polyglycolic acid (PGA) sutures. Before using the sutures in the experimental surgery, sutures Tensile Strength and SEM Analysis were performed. 12 Sprague–Dawley female rats (6 healthy, 6 diabetic) were used to create bilateral buccal mucosa punch incisions, with one side sutured using the propolis-AgNPs-coated PGA and the other with non-coated PGA sutures as a control. Wound healing was assessed after seven days through histological analysis using hematoxylin eosin and Masson’s trichrome staining. Data were analyzed using Chi-square, Fisher’s exact test, and Welch’s t test (p ≤ 0.05 considered significant). In healthy rats, propolis-coated sutures significantly improved collagen fiber organization and mature collagen deposition (p = 0.030). Although diabetic rats did not show statistically significant differences (p > 0.05), a trend toward enhanced collagen fiber alignment and mature collagen formation was observed. A slight reduction in blood vessel formation was noted in both groups. Propolis-AgNPs-coated sutures demonstrated enhanced collagen organization in healthy rats and showed potential for improving wound healing in diabetic models.
Periodontitis is a chronic inflammatory disease affecting more than 1 billion people worldwide and leading to irreversible alveolar bone loss. Although salivary biomarkers are potentially non-invasive diagnostic targets, the longitudinal changes in osteocalcin (a marker of bone turnover) following periodontal therapy have been poorly described across levels of disease progression. In this prospective longitudinal study, a new multimodal method combining salivary biomarker analysis and Cone-Beam Computed Tomography (CBCT) was employed. A total of 100 patients (25 systemically healthy controls and 75 patients with periodontitis, stratified into Stages I, II, or III according to the World Workshop 2017 classification) received non-surgical periodontal therapy (NSPT). Salivary osteocalcin and clinical parameters (PPD, CAL, PI) were evaluated at baseline, 3 months, and 6 months. The sample size was estimated by G*Power software to achieve reliable power (> 90
ObjectivesThe aim of this bibliometric analysis was to illustrate research interests and trends in the field of alveolar ridge augmentation (ARA) between 1990 and 2024.MethodsA database search was performed in the Web of Science Core Collection to retrieve relevant studies published from 1990 to 2024. Bibliometric and statistical network analyses were conducted using R language, CiteSpace, and VOSviewer. Scientific maps were then constructed for journals, countries, institutions, authors, keywords, and citations.ResultsA total of 4386 papers were published from 1990 to 2024. Both annual publication output and citations exhibited sustained growth until 2021, followed by stabilization from 2021 to 2024. The journal with the highest number of publications and citations was Clinical Oral Implants Research. At the country level, the United States ranked first, with 1000 publications, while Europe was the most productive continent. Sixty-six high-frequency keywords were selected, among which 3D printing and polycaprolactone (PCL) emerged as the most recent high-frequency keywords. Thirty papers with the strongest citation bursts were selected. Additionally, 16 reference clusters were extracted, among which dental implants (#1), titanium mesh (#2), and tooth extraction (#5) gained prominence over the past decade.ConclusionThis study provides an overview of the development and research trends of ARA. The findings indicate strong contributions from the United States and Europe. Guided bone regeneration (GBR) was the most extensively studied technique for ARA, and alveolar ridge preservation (ARP) has also received substantial attention. The latest research themes focus on advances in defect-specific regenerative strategies, including 3D printing, PCL, and electrospinning. Given the limitations inherent to retrieval from a single database, further comprehensive data analysis is needed.
Biomimetic dentistry seeks to restore the structure and function of natural tooth tissues using materials that closely approximate their biological counterparts. Despite the growing clinical adoption of materials marketed as “biomimetic” or “bioactive,” a persistent terminological ambiguity between these two terms has complicated evidence synthesis and clinical decision-making, particularly in the paediatric context. This narrative review, in which no systematic risk-of-bias assessment was performed, proposes a conceptual two-tier classification framework for biomimetic dental materials, distinguishing passive biomimetics, which replicate physical tooth tissue properties without inducing a biological response, from bioactive substances, which actively promote healing or remineralisation. Passive biomimetics encompass dental ceramics and resin-based composites. Bioactive substances are further subdivided into ion-releasing materials, bioceramic-based substances, biomolecular/bioinductive systems, and smart adhesive/hybrid systems. Each category is appraised against the FDI 2022 Policy Statement criteria for bioactive restorative materials. The proposed classification has not been prospectively validated and is intended as a conceptual framework to guide clinical reasoning and future research. Evidence quality varies considerably across categories: while materials such as glass ionomer cements and mineral trioxide aggregate are supported by extensive clinical data, emerging approaches including self-assembling peptide P11-4 and bioactive adhesive systems remain primarily supported by in vitro or short-term evidence. Future research should prioritise long-term randomised controlled trials in paediatric populations to validate the clinical relevance of emerging biomimetic strategies.
Abstract Accurate determination of age and sex is fundamental in forensic anthropology, archaeology, and clinical diagnostics. Conventional methods are often limited by subjectivity and low precision. Cone Beam Computed Tomography (CBCT), with its high-resolution three-dimensional imaging, offers a reliable alternative for evaluating craniofacial structures. This study aimed to assess the utility of atlantoaxial morphometric parameters, particularly the atlantodental interval, in age and sex determination using CBCT. A retrospective observational study was conducted on 200 full-field CBCT scans (100 males, 100 females) of individuals aged 20–80 years. Scans meeting inclusion criteria were analyzed using standardized protocols. Eight parameters related to atlas (C1) and axis (C2) morphology and atlantodental intervals (AADI, PADI, LADI) were measured. Statistical analysis included ANOVA, independent t-tests, effect size estimation, and discriminant function analysis. Most parameters showed no significant variation across age groups, except posterior atlantodental interval (PADI), which demonstrated statistical significance. Sex-based comparisons revealed significantly greater atlas and axis dimensions in males (p < 0.01), indicating marked sexual dimorphism. Effect size analysis showed very large effects for atlas measurements and moderate to large effects for axis parameters. Discriminant analysis identified axis vertical length as the most reliable predictor of sex (accuracy: 82.5%), followed by axis anteroposterior length (72%). Atlantodental interval measurements showed limited discriminatory value. Atlantoaxial parameters exhibit selective age- and sex-related variations, with axis measurements demonstrating the highest utility for sex estimation. However, overall diagnostic accuracy remains moderate, indicating that these parameters should be used adjunctively. Further large-scale studies are required to validate their application in forensic and clinical settings.
Gingival recession is a highly prevalent mucogingival condition that can significantly compromise oral health and esthetics. Patients commonly suffer from dentinal hypersensitivity, root caries, poor esthetics, discomfort during brushing, and in severe cases tooth mobility or tooth loss, ultimately affecting their quality of life. To compare the effectiveness of Platelet Rich Fibrin (PRF) and Amnio-Chorion Membrane (ACM) with Coronally Advanced Flap (CAF) to manage the case of isolated gingival recession defects (GRD). The study is a split-mouth randomised trial that included 13 patients (n = 26) with bilateral Miller Class 1 or 2 maxilla anterior and premolar recession of the gingiva. The randomizing of locations was also done to 13 sites in each group of either Group I (CAF+ PRF, n = 13) or Group II (CAF +ACM, n = 13). At 6 months follow-up, plaque Index (PI), Gingival Index (GI), Probing pocket depth (PPD), gingival recession depth (GRD), Clinical attachment level (CAL), Keratinized gingiva width (WKG), Percentage of root coverage, and root coverage Esthetic score (RES) were measured. All data were analyzed in the SPSS v21.0 software; paired t-tests and unpaired t-tests were used for comparing the intragroup and intergroup respectively. The level of statistical significance was defined as p < 0.05. At 6 months, statistically significant improvements in PRF and CAM in all clinical parameters was seen. Root coverage of Group I was 78.84 ± 19.13 and Group II was 74.99 ± 15.59. Intergroup comparisons showed no statistically significance in clinical outcome, RES or root coverage percentage (p > 0.05). PRF and ACM had both positive outcomes on gingival thickness, WKG, and CAL. PRF or ACM resulted in significant improvement in clinical periodontal parameters, root coverage, and esthetic outcomes, with no statistically significant difference between the two groups.
Endodontically treated teeth often have compromised tooth structure, which increases their susceptibility to fracture. This in vitro study compared the fracture resistance of endodontically treated mandibular premolars restored using the sandwich technique, Nayyar core composite, and semi-direct composite onlay. Seventy-six extracted mandibular premolars were randomly allocated into four groups (n = 19): intact teeth (control), conventional sandwich technique, Nayyar core composite, and semi-direct composite onlay. All groups except the control teeth group underwent standardized root canal treatment and obturation, followed by composite restoration according to the group allocation. Specimens were loaded axially in a universal testing machine until fracture. Fracture resistance was recorded in kilonewtons (kN). Data were analyzed using one-way ANOVA and Dunnett T3 post-hoc tests (p < 0.05). Mean fracture resistance was highest in the intact control group (8.70 ± 4.09 kN), followed by the sandwich technique (7.50 ± 1.55 kN), Nayyar core composite (6.10 ± 1.61 kN), and semi-direct composite onlay (4.94 ± 3.16 kN). The overall difference among the groups was statistically significant (p = 0.001). Post-hoc analysis showed significant differences between the control and semi-direct onlay groups (p = 0.019) and between the sandwich technique and semi-direct onlay groups (p = 0.022). Within the limitations of this in vitro study, the sandwich technique demonstrated the highest fracture resistance when compared with Nayyar core composite restoration and semi-direct composite onlay in endodontically treated mandibular premolars with conservative access preparation and intact marginal ridges.
