Journal of Dental Sciences最新文献

Background/purpose: -2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (THSG) is a bioactive component in the Chinese herb Polygonum multiflorum, recognized for its anti-inflammatory and lipid-lowering properties. Human dental pulp stem cells (hDPSCs) have excellent capabilities in tooth regeneration, wound healing, and neural repair. The exosomes (Exo) released by hDPSCs contain bioactive molecules that influence cell proliferation, differentiation, and immune responses. Therefore, we aimed to unveil the potential of THSG-Exo and evaluate its regenerative capabilities through the in vitro experiment and rat bone defect model.

Materials and methods: The effects of hDPSC-derived exosomes, with or without THSG treatment, on repair and bone regeneration were evaluated through in vitro and in vivo studies. Finally, we conducted a proteomic analysis to meticulously compare the compositional contents of the two types of exosomes.

Results: In vitro data showed that 10 and 100 μM THSG-Exo enhanced cell proliferation and osteogenic differentiation, reducing wound size to 40 % of its original size. In our maxillary bone defect rat model, THSG-Exo significantly increased bone volume, trabecular thickness, and bone density in the bone defect area. In addition, proteomic analysis of THSG-Exo revealed diverse proteins linked to bone differentiation and tissue repair, including bone morphogenetic protein-1 (BMP-1) and tumor necrosis factor (TNF)-α-stimulated gene 6 (TNFAIP6). Our searches in functional databases revealed that THSG-Exo is involved in numerous biological pathways.

Conclusion: THSG-Exo enhanced cell proliferation, wound healing, and osteogenesis in vitro, while also expediting tissue repair and bone regeneration in vivo. The protein diversity of THSG-Exo contributes significant value in both basic and regenerative medicine.

Background/purpose: The Lancet Infectious Diseases launched a call to action for dermatologists in the rise of syphilis. In practice, dermatologists and stomatologists perform early diagnoses of syphilis and refer patients to adequate treatment.

Materials and methods: This scientometric study aimed to investigate and compare research trends and characteristics of syphilis publications by dermatologists and stomatologists in the Scopus database, with emphasis on the analysis of the keywords that can reflect research directions and topics of concern.

Results: Among 18,120 papers on syphilis, 1981 (10.9%) and 201 (1.1%) were published by dermatologists and stomatologists, respectively. The total citation count was 18,629 and 2,376 with an h index of 52 and 25 for publications by dermatologists and stomatologists, respectively. Common keywords in papers by both dermatologists and stomatologists included male, Treponema pallidum, benzathine penicillin, differential diagnosis, human immunodeficiency virus, secondary syphilis, syphilis serology, cutaneous syphilis, neurosyphilis, congenital syphilis, lymphadenopathy, chancre, gonorrhea, rash, erythema, and papule. Distinctive keywords used by dermatologists included infant, pregnancy complications, lymphocytic infiltration, spirochete, and genetics. Keywords that included questionnaire, awareness, infection risk, attitude to health, sexual health, oral sex, and unprotected sex were used by stomatologists.

Conclusion: In the modern context, both dermatologists and stomatologists play important roles in providing early recognition and timely diagnosis of syphilis, advocating for public health campaigns aimed at increasing awareness, and improving access to care for at-risk patient populations.

Background/purpose: The impact of thermal behavior on the clinical performance of gutta-percha points (GP) is unclear. This study aimed to investigate the thermal behavior of three different types of GP and their temperature changes (TC) in a simulated clinical environment.

Materials and methods: The GP tested were Conform Fit® Gutta-Percha Points (CF), Autofit™ Feathered Tip Gutta Percha (AF), and Gutta Percha Root Canal Points (GC). The phase transition temperatures of the samples were analyzed using differential scanning calorimetry (DSC). The TC at the tips of the GP was examined with the heat source positioned at specific distances from the tip. Additionally, the TC of the GP in the apical foramen of a simulated canal during the warm vertical compaction (WVC) technique was evaluated. Differences in the apical temperature of the GP during WVC were compared using two-way ANOVA, with statistical significance set at P < 0.05.

Results: The phase transition temperatures peaked at approximately 51 °C and 61 °C. The temperature analysis showed the maximum average temperatures of AF and CF decreased to 38 °C when the heat source was 3 mm from the tip. During WVC, the average maximum apical temperatures for AF, CF, and GC were 37.7 °C, 36.0 °C, and 35.5 °C, respectively. Both the elapsed time of WVC and the brand of GP significantly (P < 0.05) affected the apical temperature.

Conclusion: The apical temperature elevation of the GP during WVC was minimal. Neither AF nor CF reached the moldable temperatures when the heat source was 3 mm away.

The shift towards virtual assessment in dental education represents a significant advancement over traditional evaluation methods, offering new opportunities for assessing both theoretical knowledge and practical skills. This review examines the use of virtual assessment tools within the context of dental education. A narrative literature review was conducted, analyzing studies published between 2000 and 2024, sourced from PubMed, the Cochrane Library, and Embase. From the initial search, 13 studies were selected for qualitative synthesis. The results indicate that virtual assessments, facilitated by technologies such as computer-based simulations and remote objective structured clinical examinations (OSCEs), have enhanced the accuracy and comprehensiveness of dental student evaluations. These methods allow for more consistent and objective assessments of competencies, addressing some limitations of traditional practical exams. However, the integration of virtual assessments presents challenges, including the need for significant investment in technology, infrastructure, and training for faculty and students. Despite these challenges, the review concludes that virtual assessment has the potential to become a cornerstone of modern dental education, offering a scalable and adaptable solution for evaluating dental competencies in diverse learning environments.

Background/purpose: This study aimed to evaluate the initial implementation of competency-based medical education (CBME) through entrustable professional activities (EPAs) in Taiwan dental education, focusing on tooth extraction EPAs across undergraduate year (UGY), postgraduate year (PGY), and oral and maxillofacial surgery-residency (OS-R) levels.

Materials and methods: Using the Delphi method, an advisory team developed and validated three levels of trial EPAs, which were implemented through the Emyway platform. A structured questionnaire was used to evaluate teachers' and students' experiences and satisfaction with Emyway and the EPAs. Data were collected from the participants at two university-affiliated hospitals in Taiwan. Statistical analyses comparing teachers' and students' experiences and satisfaction were conducted.

Results: The EQual rubric scores for the EPAs were high across all levels (UGY: 4.80, PGY: 4.78, R: 4.79) with no significant differences. The demographic characteristics and Emyway experiences were similar among 7 teachers and 17 students. No significant difference was observed in terms of satisfaction with EPA design and usage between the teachers and students. For the teachers and students, the overall Emyway satisfaction scores were 3.86 and 3.76 and the EPA content satisfaction scores were 4.00 and 3.71, respectively, with no significant differences.

Conclusion: The study successfully introduced EPAs into Taiwan dental education, demonstrating high EQual rubric scores and moderate satisfaction. Emyway is a convenient and effective platform for EPA implementation. Future efforts should focus on the expansion of EPAs to other dental specialties and integration of CBME into Taiwan dental education to align with international standards.

Background/purpose: Computer-assisted implant surgery (CAIS) is increasingly performed to reduce deviations in implant position. Dynamic CAIS or navigation systems provide instant display of implant drilling instruments and patient positions directly on the computer monitor. Augmented reality (AR) technology allows operators to visualize real-time information projected onto the lenses of AR glasses. Although AR is being used in medical applications, there are few clinical studies on applying AR glasses to dental implants. The purpose of this randomized clinical study was to compare the accuracy of implant position using the dynamic CAIS with and without AR glasses.

Materials and methods: Twenty patients who needed a single dental implant were randomly divided into two groups: combined dynamic CAIS with AR glasses (AR glasses group, n = 10) and dynamic CAIS without AR glasses (non-AR glasses group, n = 10). Three-dimensional (3D) deviations of implant platform, apex and angular deviations were measured and analyzed using independent t-tests (P < 0.05).

Results: The 3D angular deviations in the AR glasses and non-AR glasses groups were 1.47 ± 1.01° and 2.42 ± 0.76°, respectively. Mean 3D entry point and apical deviations were 0.75 ± 0.45 mm and 0.87 ± 0.45 mm in the AR glasses group, whereas the non-AR glasses group were 1.11 ± 0.44 mm and 1.18 ± 0.50 mm, respectively. There was no statistically significant difference between the two groups.

Conclusion: Implant position accuracy using dynamic CAIS with AR glasses was similar to dynamic CAIS without AR glasses during a single implant placement.

Oral and maxillofacial surgery (OMS) is a field that straddles knowledge and clinical experience from both medical and dental specialties. In the small island nation of Singapore, the rapidly and constantly changing needs of its diverse and aging population, as well as changes in the mindsets of both students and educators have led to many developments in the local OMS program. Tied to the only dental school in the country, the curriculum of the training program has kept up with the changes in the demographics and attitudes of the local patient pool, which comprises a multicultural population with both traditional and modern mindsets. Since its inception, the training program has also shifted away from the traditional apprenticeship model of surgical specialties to include more integrated and modular learning with a heavy emphasis on evidence-based medicine, simulation training workshops, and more focus on digital planning and other technological advancements. This review explores the current scope of training and practice in the Singapore landscape, and how it has evolved and been tailored to meet the needs of its patients and future clinicians.

Background/purpose: Spacing between teeth is a common trait across different stages of dentition. With the tide of the digital impression, the scanning trueness of the intraoral scanner (IOS) is a hot subject. This study aimed to determine the correlation between the level of the spaced dentition and trueness of the intraoral scanning.

Materials and methods: Four arch lengths of deciduous tooth models (spacing Model 1, Model 2, Model 3, Model 4 = 0, 1, 2, 3 mm; maxillary arch length = 73.268, 81.922, 90.776, 97.698 mm; mandibular arch length = 69.092, 76.160, 86.228, 94.344 mm) were designed to measure trueness via an IOS. Statistical analysis included one-way analysis of variance followed by post hoc Tukey tests for comparisons of the data.

Results: The trueness varied across different levels of spacing, with the highest deviation observed between intraoral and desktop scans in Model 3, followed by Model 4, Model 2, and Model 1 in the maxillary arch. In the mandibular arch, the sequence of deviation from highest to lowest was Model 4, Model 3, Model 1, and Model 2. Significant differences were observed among these models in both the maxilla and mandible (P < 0.001).

Conclusion: In both the maxilla (2 mm spacing, arch length ≥81.922 mm) and mandible (3 mm spacing, arch length ≥86.228 mm), scanning accuracy decreases with longer arch lengths. This indicates that as arch length increases, so does the deviation in scanning accuracy. Therefore, the clinician should notice the deviation when using IOSs for the spaced cases.

Background/purpose: Titanium (Ti) is extensively used in dental and orthopedic implants due to its excellent mechanical properties. However, its smooth and biologically inert surface does not support the ingrowth of new bone, and Ti ions may have adverse biological effects. The purpose is to improve the corrosion resistance of titanium and create a 3D structured coating to enhance osseointegration through a very simple and fast surface treatment.

Materials and methods: This study investigated the use of sandblasting, acid etching, and NaOH leaching to produce porous Ti implants with enhanced biological activity and corrosion resistance.

Results: These surface modifications generated a mixed oxide layer resembling the extracellular matrix (ECM), consisting of a dense amorphous TiO2 inner layer (50-100 nm thick) and a TiO2 outer layer with interconnected pores (pore size 50-500 nm; 150-200 nm thick). The inner layer significantly improved corrosion resistance, while the hydrophilic outer layer, with its porous structure, facilitated protein albumin adsorption and promoted the attachment, proliferation, and mineralization of human bone marrow mesenchymal stem cells.

Conclusion: The combined surface treatment approach of sandblasting, acid etching, and NaOH leaching offers a comprehensive solution to the challenges associated with titanium implants' biological inertness and corrosion susceptibility. By enhancing both the biological activity and corrosion resistance of Ti surfaces, this protocol holds significant promise for improving dental and orthopedic implants' success rates and longevity. Future studies should focus on in vivo assessments and long-term clinical trials to further validate these findings and explore the potential for widespread clinical adoption.

Background/purpose: Daily flushing of dental unit waterlines is important for infection control. However, the effect of flushing on water quality management in portable dental units (PDUs) for mobile dental treatments remains unclear. In this study, we aimed to investigate the factors affecting the effectiveness of PDU flushing.

Materials and methods: Free residual chlorine concentration (FRCC) and heterotrophic plate counts (HPCs) in handpiece discharge water were evaluated as water quality indicators to determine the effectiveness of flushing PDUs, considering flushing duration, periods of PDU use, FRCC in the water used, pre-water drainage in water tanks and waterlines, and season. The effect of flushing on heterotrophic bacterial flora was analyzed by 16S rRNA gene sequencing.

Results: PDUs with longer usage periods required a longer flushing duration for FRCC recovery. FRCC reached the standard level for water quality in Japan after at least 20 s of flushing. Flushing changed heterotrophic bacterial flora close to that of fresh tap water by reducing Sphingomonas. Flushing with purified water or stagnant tap water with insufficient FRCC did not allow the HPCs to reach the target level. Without pre-water drainage of the water tanks and waterlines in the summer, the HPCs did not always reach the target level, even with flushing.

Conclusion: Periods of PDU use, pre-water drainage, water temperature, and FRCC substantially affect the effectiveness of PDU flushing. Flushing for at least 20 s with water containing appropriate free residual chlorine effectively restores the water quality of PDUs.