Search Results (140)

The integration of artificial intelligence (AI) and advanced digital workflows is revolutionising full-arch implant dentistry, particularly for geriatric patients with edentulous and atrophic arches, for whom achieving both prosthetic passivity and optimal aesthetic outcomes is critical. This narrative review evaluates current challenges in intraoral scanning accuracy—such as scan distortion, angular deviation, and cross-arch misalignment—and presents how innovations like the Medit SmartX AI-guided workflow and the Scan Ladder system can significantly enhance precision in implant position registration. These technologies mitigate stitching errors by using real-time scan body recognition and auxiliary geometric references, yielding mean RMS trueness values as low as 11–13 µm, comparable to dedicated photogrammetry systems. AI-driven prosthetic design further aligns implant-supported restorations with facial symmetry and smile aesthetics, prioritising predictable midline and occlusal plane control. Early clinical data indicate that such tools can reduce prosthetic misfits to under 20 µm and lower complication rates related to passive fit, while shortening scan times by up to 30% compared to conventional workflows. This is especially valuable for elderly individuals who may not tolerate multiple lengthy adjustments. Additionally, emerging AI applications in design automation, scan validation, and patient-specific workflow adaptation continue to evolve, supporting more efficient and personalised digital prosthodontics. In summary, AI-enhanced scanning and prosthetic workflows do not merely meet functional demands but also elevate aesthetic standards in complex full-arch rehabilitations. The synergy of AI and digital dentistry presents a transformative opportunity to consistently deliver superior precision, passivity, and facial harmony for edentulous implant patients. Full article

Objectives: The relationship between oral health and general health of geriatric in-hospital patients (GIH) who are poly-morbid and edentulous is currently unclear. This study determined the relationship between oral health and general health, and further implications and recommendations were derived. Methods: This retrospective cohort study included 81 GIH patients with impairment of oral state and masticatory function and need for immediate prosthetic treatment. The number of medical diagnoses, particularly main diagnoses of being hospitalized, comorbid diagnoses and the dental/oral state, were evaluated. Laboratory data of vitamin D3 and albumin concentrations were measured. Intraoral risk factors (IRF) affecting the masticatory function were intraoral inflammation, mucogingival impairment (MGI) and severe bone crest atrophy (SBCA). Masticatory function was evaluated by DMF*-T Index (number of destroyed/diseased, missing teeth and artificial fabrication), Eichner Index and Scores. The clinical relevance was surveyed by significance and effect size calculations. Results: In GIH, the number of medical diagnoses correlated significantly with the occurrence of IRFs. SBCA was the most affecting IRF, as measured by Eichner Index at baseline (p = 0.001). Single main diagnoses CNS and gastro-intestinal disease (GID) correlated with both deficiency of vitamin D3 levels (p = 0.011; p = 0.028) and hypoalbuminemia (p = 0.013; p = 0.023). Single comorbid diagnoses significantly correlated with both vitamin D3 deficiency and hypoalbuminemia (CVD (p = 0.031); DM (p = 0.042). Hypoalbuminemia was further found to be correlated with the sum of comorbid diagnoses (p = 0.033). Conclusions: GIH patients suffered from general and dental poly-morbidity. The prevalence of diseases was higher due to SBCA and impaired masticatory function. Deficiency of vitamin D3 and hypoalbuminemia were possible malnutrition markers. Full article

Background/Objectives: With aging linked to increased oral health conditions, the communication skills of dental professionals are vital to ensure patient satisfaction and improve the quality of geriatric dental care. This cross-sectional study evaluated geriatric patients’ satisfaction with communication at a university dental clinic, comparing interactions with dentists and fifth-year dental students. Methods: A self-report questionnaire was administered to 111 patients, assessing sociodemographic data, general health, and satisfaction across six communication dimensions: verbal and nonverbal communication, empathy, respect, problem-solving, and support materials. The data were analyzed using Mann–Whitney U tests (α = 0.05). Results: The geriatric patients exhibited higher levels of satisfaction when interacting with dentists compared to students, particularly in the domains of nonverbal communication (p = 0.007), empathy (p = 0.035), and respect (p = 0.017). However, no statistically significant differences (p > 0.05) were observed in terms of verbal communication, problem-solving, and support materials. Conclusions: The geriatric patients demonstrated greater satisfaction with interactions with practicing dentists. These findings indicate that an attending dentist’s clinical experience enhances interpersonal interactions with geriatric patients. Therefore, developing the interpersonal skills of future dentistry professionals, as well as adapting communication to the needs of the elderly, is essential to provide more satisfactory experiences in geriatric dental care. Full article

Background/Objectives: This ex vivo study aimed to evaluate the diagnostic performance of ultra-low-dose (ULD) cone-beam computed tomography (CBCT) protocols in detecting vestibular bone defects for immediate implant planning, using intraoral scan (IOS) data as a reference. Methods: Four CBCT protocols (ENDO, A, B, C) were applied to four dried human skulls using a standardized setup and a single CBCT unit (Planmeca ProMax^® 3D Mid, Planmeca Oy, Helsinki, Finland). All scans were taken at 90 kV, with varying parameters: (1) ENDO (40 × 50 mm, 75 µm, 12 mA, 80–120 µSv, 15 s), (2) A (50 × 50 mm, 75 µm, 9 mA, 20–40 µSv, 5 s), (3) B (100 × 60 mm, 150 µm, 7.1 mA, 22–32 µSv, 5 s), and (4) C (100 × 100 mm, 200 µm, 7.1 mA, 44 µSv, 4 s). Vestibular root surfaces of single-rooted teeth (FDI regions 15–25 and 35–45) were digitized via IOS and exported as STL files. CBCT datasets were superimposed using 3D software (Blender 2.79), and surface defects were measured and compared using one-sample t-tests and Bland–Altman analysis. The level of significance was set at p < 0.05. Results: A total of 330 vestibular surfaces from 66 teeth were analyzed. Compared to the IOS reference, protocols ENDO and A showed minimal differences (p > 0.05). In contrast, protocols B and C exhibited statistically significant deviations (p < 0.05). Protocol B demonstrated a mean difference of −0.477 mm² with limits of agreement (LoA) from −2.04 to 1.09 mm² and significant intra-rater variability (p < 0.05). Protocol C revealed a similar mean deviation (−0.455 mm²) but a wider LoA (−2.72 to 1.81 mm²), indicating greater measurement variability. Overall, larger voxel sizes were associated with increased random error, although deviations remained within clinically acceptable limits. Conclusions: Despite statistical significance, deviations for protocols B and C remained within clinically acceptable limits. ULD CBCT protocols are, thus, suitable for evaluating vestibular bone defects with reduced radiation exposure. Full article

Background/Objectives: Oral health is an important element of overall health and quality of life. However, few studies have evaluated the association between quality of life (QOL) and oral function, including tongue and lip movements. This study aimed to investigate the relationship between oral-related QOL and oral function, including tongue and lip movements, in independent elderly people. Methods: The participants were 143 community-dwelling elderly people in Taiwan (40 men, 103 women; 76.4 ± 6.4 years). We used the General Oral Health Assessment Index (GOHAI) to evaluate oral-related QOL. The items used to evaluate oral function were as follows: the speed of tongue movement from side to side, maximum tongue pressure, maximum lip pressure, the repeated saliva swallowing test, oral diadochokinesis (speed and dexterity when pronouncing /pa/, /ta/, and /ka/), and masticatory performance. In addition, we surveyed the number of remaining teeth, denture use, and awareness of problems at mealtimes. For the analysis, we compared the GOHAI score for each group, divided by cutoff values. Results: The univariate analysis revealed significant differences in the GOHAI score according to denture use, the number of remaining teeth, the state of occlusal support areas, the speed of tongue movement from side to side, oral diadochokinesis /ta/ and /ka/, and masticatory performance. The logistic regression analysis revealed that oral diadochokinesis /ka/ was a significant explanatory variable for low GOHAI scores (odds ratio = 13.145). Conclusions: Our results imply that lower oral-related QOL was associated with slow motor function at the rear area of the tongue. Full article

Background: Iron metabolism has emerged as a critical factor in cancer biology, with elevated intracellular iron levels contributing to increased oxidative stress and tumorigenesis. However, the molecular determinants governing ferroptosis sensitivity remain incompletely understood. Triosephosphate isomerase 1 (TPI1), a key glycolytic enzyme, has been implicated in cancer progression, but its role in ferroptosis regulation, particularly in the context of chemoresistance, is largely unexplored. In this study, we investigated the impact of TPI1 silencing on ferroptosis in cisplatin-resistant oral squamous cell carcinoma (OSCC), aiming to elucidate its mechanistic role and therapeutic potential. Methods: We conducted in vitro and in vivo analyses to evaluate the functional consequences of TPI1 knockdown in cisplatin-resistant OSCC cell lines and tumor xenograft models. The effects of TPI1 silencing and/or cisplatin treatment were assessed with respect to cell proliferation, migration, and invasion, along with ferroptosis-associated markers, including lipid ROS, free iron levels, lipid peroxidation, and the expression of key ferroptosis-related genes. Additionally, we analyzed the clinical relevance of TPI1 expression in human OSCC tissue samples, examining its association with clinicopathological features and patient prognosis. Results: TPI1 was found to be significantly upregulated in both OSCC tissues and cell lines, and high TPI1 expression correlated with poor clinical outcomes. Multivariate analysis identified TPI1 as an independent prognostic factor for tumor progression. Functionally, TPI1 knockdown suppressed OSCC cell proliferation, migration, and invasion, while its overexpression enhanced these oncogenic behaviors. Mechanistically, silencing TPI1 led to increased intracellular ROS accumulation, elevated free iron, and enhanced lipid peroxidation, collectively promoting ferroptotic cell death in cisplatin-resistant OSCC cells. In vivo, TPI1 depletion resulted in marked tumor growth inhibition and synergized with cisplatin to further suppress tumor burden in xenograft models. Moreover, TPI1 silencing disrupted the epithelial–mesenchymal transition (EMT), a key driver of cancer metastasis and drug resistance. Conclusions: Our study reveals a previously unrecognized role of TPI1 in protecting oral cancer cells from ferroptosis, especially in the setting of cisplatin resistance. These findings suggest that TPI1 not only contributes to tumor aggressiveness but also mediates resistance to ferroptosis. Targeting TPI1 may therefore represent a promising therapeutic strategy to overcome chemoresistance and enhance ferroptosis-based therapies in oral cancer. Full article

The limitations of traditional, autologous bone grafts, such as the scarcity of donor material and the risks of secondary surgical trauma, have spurred the development of alternatives for the repair of large bone defects. Bionic bone scaffolds fabricated via fused deposition modeling (FDM)—a three-dimensional (3D) printing technique—are considered promising. While gyroid-structured scaffolds mimic the complex micro-architecture of cancellous bone, their application in FDM 3D printing remains understudied. Furthermore, no consensus has been reached on the ideal pore size for gyroid scaffolds, which is influenced by the infill density. In this study, we fabricated five groups of polycaprolactone/hydroxyapatite (PCL/HA) scaffolds with different infill densities (40%, 45%, 50%, 55%, and 60%) using a solvent-free filament preparation method. Scanning electron microscopy (SEM) observation showed that all scaffolds exhibit an interconnected porous structure. The scaffold with the 55% infill density, featuring a pore size of 465 ± 63 μm, demonstrated optimal hydrophilicity and mechanical properties comparable to natural cancellous bone. In addition, this scaffold supported cellular bridging within its pores and showed the highest alkaline phosphatase (ALP) activity and calcium salt deposition. Our findings offer novel insights into the design of gyroid-like scaffolds and their fabrication via FDM, paving the way for potential clinical applications. Full article

Background: Osteoporosis is a global health problem that significantly decreases patients’ quality of life and causes tremendous medical burdens. Therefore, exploring effective targeting strategies for osteoporosis treatment is crucial. Previous studies have indicated that pleiotrophin (PTN) was a secretory factor involved in several biological processes, such as angiogenesis, neural development, and abnormal osteogenic functions in osteoporosis. However, the roles of PTN in osteogenics and the mechanisms remain unclear. Methods: In this study, we explored the effects and mechanisms of PTN in regulating osteogenic functions using real-time quantitative PCR, immunofluorescence, ALP detection, a TUNEL assay, RNA sequencing, and phosphorylation quantitative proteomics. Fracture-healing experiments in osteoporosis rats were also conducted to evaluate the osteogenic functions of PTN in vivo. Results: We found that PTN significantly inhibited apoptosis and promoted the osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs). Further experiments showed that PTN regulated the biological functions of rBMSCs by promoting antioxidant functions and reducing cellular reactive oxygen species (ROS), thereby protecting rBMSCs from accumulated ROS. Additionally, we found that PTN binds to the PTPRZ1 receptor, inducing intracellular PLCG1 phosphorylation and NCOA3 nuclear translocation, which regulate the downstream antioxidant functions of rBMSCs. Additionally, we verified that PTN effectively promoted fracture healing in osteoporotic animals. Conclusions: This study elucidates the mechanisms by which PTN promotes osteogenesis and verifies this effect in vivo, offering an effective target for osteoporosis treatment. Full article

Aims: This in silico study aimed to investigate the effect of implant–abutment contact surfaces on the stress generation of Morse taper implants under oblique loading. Materials and methods: Three-dimensional finite element models of Bone-Level and Tissue-Level implants were simulated with Standard and Partial contacts between the abutment and implant. The dimensional parameters followed the ISO 14801 guidelines, and an oblique load of 300 N was applied to the implants. The von Mises stress was acquired. Results: The Tissue-Level design showed a significant difference in the stress level when the connection with the implant, abutment, and screw was Partial. For the implant fixture, abutment, and screw, the Tissue-Level design showed 13% more stress in the implant, abutment, and screw when the connection was Partial. The Bone-Level design did not affect the connection and showed an overall 42% lower stress than the Tissue-Level design for the implant fixture. However, in the screw, there was a difference between the Bone-Level implants with a Standard and Partial connection. In contrast, for the Tissue-Level implant, this difference was less evident with higher stress peaks in the entire set. Conclusion: To achieve optimal outcomes, it is highly recommended to use original abutments, as they provide a more precise fit. The stress peaks were notably lower in Bone-Level implants compared to Tissue-Level implants. Furthermore, an implant–abutment connection with more contacting areas significantly reduced stress concentration, especially in Tissue-Level implant designs. By choosing well-fitting abutments, one can ensure more stable and durable implant performance with less stress. Full article

Background/Objectives: Macronutrients (protein, fat, and carbohydrate) provide sources of energy and play crucial roles in various physiological functions. However, sex differences in the relationships between protein, fat, and carbohydrate intakes and all-cause mortality remain unclear. The present study investigated sex differences in the relationships between protein, fat, and carbohydrate intakes and all-cause mortality using longitudinal epidemiological data. Methods: A total of 3743 healthy residents (1666 men and 2077 women) aged 40 years or older were followed up (men: 6.64 ± 1.51 years, women: 6.76 ± 1.28 years from 2013) in Shika Town, Ishikawa Prefecture, Japan. Nutrient intake was assessed at the baseline survey using the Brief Self-Administered Dietary History Questionnaire. The prospective relationship between baseline nutrient intake and all-cause mortality during the follow-up period, stratified by sex, was evaluated using two-way analysis of covariance and multiple logistic regression analysis, adjusted for age and BMI. Results: We documented 330 deaths (179 men and 151 women) during the 10-year follow-up period. Significant interactions between death and sex were observed for the intake of total protein (p < 0.001), animal protein (p < 0.001), vegetable protein (p = 0.033), total fat (p = 0.012), and animal fat (p = 0.024). Multiple logistic regression analysis demonstrated that total protein (p = 0.004), and animal protein (p = 0.010) decreased the all-cause mortality and increased carbohydrates (p = 0.046) in women. In men, total fat (p = 0.017) decreased the all-cause mortality. Conclusions: The present study revealed distinct sex differences in the effects of total protein, animal protein, and carbohydrate intakes on all-cause mortality. This sex difference may be due to the sex differences in nutrients intake themselves. Full article

Background/Objectives: Undernutrition increases the mortality risk in older persons requiring long-term care; further, it is associated with oral functions such as swallowing and chewing. Moreover, occlusion affects oral function and is crucially involved in nutritional intake. The present study aimed to examine the association between the number of molar occlusions and undernutrition according to body mass index (BMI) in older persons requiring long-term care. Methods: Japanese older persons requiring long-term care were categorized based on BMI (<20 kg/m² vs. 20 kg/m²). We examined the association between undernutrition and the number of molar occlusions (one in each of the left and right premolars and molars, for a total of four). Results: Among 893 included participants, 440 (49.3%) had BMI < 20 kg/m² and 453 (50.7%) had BMI > 20 kg/m². Binomial logistic regression analysis revealed that BMI < 20 kg/m² was significantly associated with increased number of molar occlusions (odds ratio: 0.52–0.70, 95% CI: 0.28–1.00). This indicated that a decrease in the number of molar occlusions was associated with malnutrition as determined through BMI in older persons requiring long-term care and residing in long-term care insurance facilities in Japan. Conclusions: Our findings suggest that maintaining occlusal support may help maintain nutritional status in older persons requiring long-term care. Full article

Highly translucent zirconia (TZ) is frequently used in dentistry. The properties of several highly translucent zirconia materials available in the market require an in-depth understanding. In this study, we assessed the translucency, crystalline phase, mechanical properties, and microstructures of three newly developed highly translucent zirconia materials (Zpex 4. m, 4 mol% yttria-stabilized zirconia: 4YSZ; Zpex Smile.m, 5YSZ; ZR Lucent ULTRA, 6YSZ). The translucency parameter (TP) was analyzed using the CIELAB system. X-ray diffraction was conducted for the crystalline phase analysis, followed by Rietveld refinement. A biaxial flexural strength test using the Weibull analysis was performed to evaluate the mechanical properties. Scanning electron microscopy, grain size distribution, and average grain size were used to analyze the microstructures. The TP content of the ZR Lucent ULTRA was the highest among the samples investigated. The Rietveld analysis revealed that the cubic zirconia phase content of the ZR Lucent ULTRA was the highest. The biaxial flexural strength of the ZR Lucent ULTRA was the lowest (622.9 MPa). The average grain size and proportion of large grains (1.0 µm < x) were the highest in ZR Lucent ULTRA. Therefore, extra-high translucent zirconia has the potential for use in anterior monolithic restorations owing to its esthetics and strength. Full article

Although in vivo studies have explored the relationship between oral environment and microbial communities, a precise analysis of the effects of environmental pH on oral microbiota remains challenging owing to their complexity and external influences. This study aimed to investigate the effect of environmental pH on the structure and diversity of oral microbiota in vitro. Tongue coating samples from ten participants were cultured anaerobically at six pH levels (5.5–8.0) using adjusted media. After DNA extraction, high-throughput sequencing of the 16s rRNA V3–V4 region was performed. Microbial diversity was analyzed using alpha and beta diversity indices, and differential taxa were identified using linear discriminant analysis effect size (LEfSe). Alpha diversity analysis revealed reduced diversity at pH 5.5 and 8.0. Beta diversity revealed that microbial communities at pH 5.5, 7.5, and 8.0 were separated from those at pH 7.0. LEfSe identified bacterial species that were significantly altered at pH 5.5 and 8.0. Environmental pH significantly influences the diversity and composition of microbial communities, with substantial changes occurring under acidic or alkaline conditions. These findings provide deeper insight into how oral biofilms respond to pH variations, underscoring the critical role of pH in oral microbiota dynamics. Full article

Salivary biomarkers are promising molecules for diagnosing systemic diseases. Cytidine/uridine monophosphate kinase 2 (CMPK2) is associated with various systemic diseases. However, little is known about the role of the CMPK2 gene in saliva and dyslipidemia. This study investigated the relationship between serum lipid levels and Cmpk2 mRNA expression in the saliva of dyslipidemic mice. Additionally, immunofluorescence staining was employed to assess the localization of the CMPK2 protein in the submandibular gland. Two types of dyslipidemic mice were utilized: mice fed a high-fat and high-cholesterol (HFHC) diet and genetically dyslipidemic ApoE-deficient mice. The mice at 9 to 46 weeks were analyzed for serum lipid levels, Cmpk2 mRNA expression in saliva, and CMPK2 protein localization in the submandibular glands. Both dyslipidemic mice displayed elevated low-density lipoprotein cholesterol and total cholesterol in serum. ApoE-deficient mice apparently exhibited increased Cmpk2 expression in saliva. Immunofluorescence staining indicated that CMPK2 proteins were primarily localized in the serous acini, potentially associated with the secretion of Cmpk2 mRNA in saliva. These findings suggest that Cmpk2 mRNA increases and is detectable in the saliva of dyslipidemic mice, providing a viable experimental model to assess the potential use of CMPK2 as a biomarker for dyslipidemia. Full article

The study investigated the impact of aging on surface roughness, color stability, and biocompatibility of hybrid resin-ceramic materials. A total of 225 specimens were produced from three three-dimensional (3D)-printed (HarzLabs Dental Sand Pro (HL), BEGO VarseoSmile Crown plus (BV), Voco V-Print c&b temp (VV)) and one milled material (Voco Grandio Blocs (VG)). Specimens were grouped into untreated, polished, and glazed surfaces. 5000 thermal cycles simulated aging. Surface roughness and color stability were analyzed, and surface topography was observed using scanning electron microscopy (SEM). Biocompatibility was evaluated with L929 cells. Surface roughness differed significantly between untreated and other groups, with no changes before and after artificial aging. Untreated milled samples were significantly smoother than 3D-printed ones. SEM analysis revealed roughest surfaces in untreated 3D-printed specimens. Polished and glazed specimens were smoother than untreated ones. Color values showed significant differences between untreated and treated/aged groups. No material showed cytotoxicity. In summary, untreated VG was smoother than 3D-printed materials, but polishing and glazing reduced roughness to levels comparable to VG. Surface treatments induced color changes, with glazing causing more changes than polishing. Aging affected color stability and biocompatibility but not surface roughness. All materials showed acceptable color changes and good biocompatibility. Full article