A Review of Stem Cell Attributes Derived from the Oral Cavity.

Oral cavity stem cells (OCSCs) have been the focus of intense scientific efforts due to their accessibility and stem cell properties. The present work aims to compare the different characteristics of 6 types of dental stem cells derived from the oral cavity: dental pulp stem cells (DPSC), stem cells from human exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSC), stem cells from the apical papilla (SCAP), bone marrow mesenchymal stem cells (BMSC), and gingival mesenchymal stem cells (GMSC). Using immunofluorescence and real-time polymerase chain reaction techniques, we analysed the cells for stem cell, differentiation, adhesion, and extracellular matrix markers; the ability to proliferate in vitro; and multilineage differentiation potential. Markers such as vimentin, CD44, alkaline phosphatase, CD146, CD271, CD49f, Oct 3/4, Sox 9, FGF7, nestin, and BMP4 showed significant differences in expression levels, highlighting the heterogeneity and unique characteristics of each cell type. At the same time, we confirmed that all cell types successfully differentiated into osteogenic, chondrogenic, or adipose lineages, with different readiness. In conclusion, our study reveals the distinct properties and potential applications of various dental-derived stem cells. These findings contribute to a deeper understanding of OCSCs and their significance in future clinical applications.

Experimental study on dimensional variations of 3D printed dental models based on printing orientation.

This research investigates the trueness and precision of 3D printing technology in dental applications, specifically focusing on dimensional variations observed in models printed at different angles. The methodology involved importing a dental model into slicing software, adjusting its orientation, and implementing support structures for stability. Subsequently, the model underwent 3D printing five times for each orientation using appropriate equipment and underwent post-processing steps, including cleaning, washing, and UV-light post-curing. The printed models were then scanned using a specialized desktop scanner for further analysis. Accuracy assessment was carried out using dedicated software, employing an algorithm for precise alignment by comparing the scanned files. Color deviation maps were utilized to visually represent variations, aiming to evaluate how positioning during printing influences the trueness and precision of 3D-printed dental models. Trueness and precision analyses involved the Shapiro-Wilk test for normality and a one-way ANOVA to compare means of three independent groups, with statistical analyses conducted using IBM SPSS Statistics software. The color maps derived from 3D comparisons revealed positive and negative deviations, represented by distinct colors. Comparative results indicated that models positioned at 0° exhibited the least dimensional deviation, whereas those at 90° showed the highest. Regarding precision, models printed at 0° demonstrated the highest reproducibility, while those at 15° exhibited the lowest. Based on the desired level of precision, it is recommended that printed models be produced at an inclination angle of 0°.

Dental Students' and Dental School Graduates' Practical Skills: An International Survey of Perceptions of National Dental Associations in Europe.

PURPOSE: Dental students learn knowledge and practical skills to provide oral health care to the population. Practical skills must be maintained or continuously developed throughout a professional career. This cross-sectional survey aimed to evaluate the perception of practical skills of dental students and dental-school graduates by national dental associations (NDAs) in international comparison in the European Regional Organization of the FDI World Dental Federation (ERO-FDI) zone. MATERIALS AND METHODS: A questionnaire of 14 items collected information on pre-/postgraduate areas. RESULTS: A total of 25 countries participated (response rate: 69.4%), with 80.0% having minimum requirements for practical skills acquisition and 64.0% starting practical training in the 3rd year of study. In countries where clinical practical work on patients begins in the 2nd year of study, practical skills of graduates are perceived as average, starting in the 3rd year of study as mainly good, starting in the 4th as varying widely from poor to very good. In total, 76.0% of respondents feel that improvements are needed before entering dental practice. Improvements could be reached by treating more patients in dental school (32.0%), increasing the quantity of clinical training (20.0%), or having more clinical instructors (12.0%). In 56.0% of the countries, it is possible to open one's own dental practice immediately after graduation, and in 16.0%, prior vocational training is mandatory. CONCLUSIONS: All participating countries in the ERO-FDI zone reported practical training in dental school, most starting in the 3rd year of study. The perception of practical skills of dental students and dental-school graduates among NDAs is very heterogeneous. Reasons for the perceived deficiencies should be further explored.

Gingival Manifestations in Oral Chronic Autoimmune Bullous Diseases: A Retrospective Study.

Background and Objectives: Desquamative gingivitis (DG) is a clinical term indicating "peeling gums" and is associated with different oral manifestations. In this study, we aimed to assess the association between DG and autoimmune blistering mucocutaneous diseases (ABMD) with oral manifestations. Materials and Methods: A retrospective study including 88 patients diagnosed between 1998 and 2019 with ABMD (intraepithelial and subepithelial autoimmune blistering diseases) was performed at the Oral Medicine Department, Faculty of Dentistry, "Carol Davila" University of Medicine and Pharmacy in Bucharest. For each patient, the sociodemographic and anamnestic data, as well as clinical features of oral lesions (location), histological evaluation, and direct immunofluorescence data were collected. Results: Most of the patients involved in the study were female (78.4%). In total, 34 patients (38.63%) were diagnosed with subepithelial autoimmune diseases (SAD) and 54 (61.36%) had intraepithelial autoimmune diseases (IAD). Differences in the anatomic distribution of oral involvement were found between SAD and IAD. The presence of DG was significantly more common in patients with SAD compared to those with a diagnosis of IAD. Conclusions: Specific anatomical locations of the oral lesions are significantly associated with different subtypes of ABMD, with gingiva and hard palate mucosa being more involved in SAD and the soft palate and buccal mucosa in IAD. Desquamative gingivitis is a clinical sign that raises diagnostic challenges for several conditions in oral medicine.

The Presence of Women in the Dental Profession: A Global Survey.

OBJECTIVES: The aim of this research was to acquire knowledge about the female dental workforce, identifying factors to pursue specialty training and career choices and working in dental institutions/associations. METHODS: An original online questionnaire was developed, validated (n = 22), and sent to 189 member associations in 133 countries of the Women Dentists Worldwide section of the FDI World Dental Federation. RESULTS: In all, 3232 female dentists from 81 countries participated. Results were divided into 5 geographic areas by continent. Difference in proportion amongst questionnaire items was evaluated with χ2 test or Fisher exact test. Ordinal multinomial linear regression analysis was performed to evaluate the association of questionnaire items with total work experience in dentistry (in years), motivation to study dentistry, type of specialisation, working hours per week, perception of female dentists about working hours, sex-based inequalities, job security after maternity leaves, as well as involvement in political organisations within their country of residence and their role in dental associations. A majority of participating female dentists are self-employed (57.7%), and 60.0% have 10 to 30 years of experience. The most popular form of practice is the single private practice (29.7%), followed by the group private practice (28.8%). Further, 44.8% work 31 to 40 h/wk, 29.1% part-time up to 30 h/wk, and 26.0% more than 40 h/wk. CONCLUSIONS: Women are still poorly represented in professional organisations, and few are officers in representative assemblies, members of the board, or president. Family life with children influences perceptions and has an impact on professional life, especially in academia and political/professional associations, so that taking on leadership positions poses additional challenges.

An atypical anatomy of permanent mandibular second molar with five roots.

Especially in molars that may have sometimes aberrant additional root canals, the complexity of tooth internal morphology in individual cases sometimes does not match to admitted classification rules and underlines the risk of missed anatomy during the endodontic management. To our knowledge, a permanent mandibular second molar with independent five roots, three mesial and two distal, each of them harboring a single canal, was not yet reported. Despite the treatment difficulties this tooth could be successfully approached by using dental operative microscope and cone-beam computed tomography (CBCT) with small field of view. Though CBCT is not a routine imagistic examination, in case of atypical tooth anatomy aiming to establish adequate diagnosis and treatment plan, the successful clinical outcome prevails over the irradiation dose.

Effects of Diet Consistency on Rat Maxillary and Mandibular Growth within Three Generations-A Longitudinal CBCT Study.

BACKGROUND: In this study, wistar rats were used to examine the impact of diet consistency on maxillary and mandibular growth over three generations. METHODS: In this investigation, a breeding sample of 60 female and 8 male wistar rats was used. Measuring was only performed on female animals. The first generation's primary breeding sample consisted of 20 female wistar rats that were 30 days old and 4 male rats that were also 30 days old; two subsequent generations were created from these animals. At the age of 100 days, CBCTs were collected of all male rats. Twenty-eight craniofacial landmarks were selected for the linear measurements on stl format extracted from the DICOM files. A Bonferroni test was performed for the statistical analysis. RESULTS: Means of measurements of all soft diet groups compared to corresponding measurements of the hard diet groups were significantly different. According to linear measurements, there was statistical difference on the maxillary measurements between the soft diet groups of the first and third generation, while the rest did not appear to have any statistical difference. There was significant difference for the mandibular dimensions only when the first generation soft diet group was compared with the third generation soft diet group. CONCLUSIONS: Food consistency has a significant impact on the growth and development of the maxilla and mandible. Soft diet habits may result in retrognathic mandible, and narrower maxilla.

Digital Workflow for Producing Hybrid Posts and Cores.

A novel and straightforward digital workflow is described to aid clinicians in producing in-office hybrid posts and cores. The method is based on scanning and using the basic module of a computer-assisted design and computer-assisted manufacturing (CAD-CAM) software program for dental applications. The applicability of the technique in a digital workflow is the simplicity of in-office production of a hybrid post and core that can be delivered to the patient in the same day.

Oral leukoplakia: A clinicopathological study and malignant transformation.

OBJECTIVES: To assess the clinicopathological characteristics of a cohort of patients with oral leukoplakia (OL) managed in a Romanian dental hospital and to evaluate the risk of malignant transformation (MT). MATERIALS AND METHODS: We conducted a hospital-based retrospective study using the clinical charts of patients diagnosed with OL that had complete clinical and histopathological evaluation followed up for 1-16 years. RESULTS: From 120 included patients, 68 (56.7%) were females, and 71 (59.2%) were current smokers. The homogeneous form was present in 60% of cases; the buccal mucosa was the most frequently involved site. MT was observed in 9 cases, which was more common in females and in those with dysplastic leukoplakia. A significant statistical association was found between MT and dysplasia grade (χ2 test: p = 0.007). MT occurred during a mean interval of time 75 months in both treated and non-treated patients. CONCLUSIONS: In this leukoplakia cohort, most of the lesions encountered were in smokers, clinically homogeneous and 62.5% proved histologically benign. But despite the clinically benign appearance of leukoplakia, tissue diagnosis of some cases was carcinoma. The results of the current study advocate the necessity for biopsy even in apparently homogeneous, clinically benign lesions. The malignization rate was 7.5%; two-thirds were nonhomogeneous lesions.

Complete morphofunctional oral rehabilitation by physiological increase of occlusal vertical dimension according to computerized mandibular scanner.

Increasing the occlusal vertical dimension (OVD) is often indicated in complex oral rehabilitation to gain restorative space and improve the occlusal relationship and aesthetics. The effect of increasing the OVD on lower facial height and facial aesthetics is not well understood and evaluated. The authors present the philosophy of the neuromuscular concept and illustrate it through a case report of a 58-year-old female patient who presented severe deep bite, bruxism, and temporomandibular disorders (TMDs). After clinical evaluation, the extraoral examination showed a reduction of the lower facial height, protuberant lips, wrinkles, and over-closed commissures. In addition, intraoral examination showed a severe anterior deep bite articulation, and the upper incisors completely covering the lower incisors labial surfaces. Through the philosophy of the neuromuscular concept the diagnostic ability, the quality and stability of the treatment increases. A temporary long-term fixed prosthesis was made at the enlarged OVD to be used in the first stage of the rehabilitation. Compared to the initial situation, the new prosthesis was delivered at a vertical dimension (VD) higher with 7 mm. The purpose of the neuromuscular philosophy and methodology is to harmonize the facial profile, functional occlusion, the joint function, and neuromuscular control. Through the neuromuscular methodology, we can assess the patient's ability to manage a significant increase in VD and to restore a functional OVD by physiological measurements.

Diabetes mellitus: Plasticizers and nanomaterials acting as endocrine-disrupting chemicals (Review).

Various plasticizers and nanomaterials have been linked to endocrine disruptors or endocrine-disrupting chemicals (EDCs) which represent a large, heterogeneous, yet incompletely understood group of structures acting on normal and pathological body pathways such as hormonal production, secretion, transport and receptor binding. By contrast, various applications of nanoparticles are currently under investigation since the delivery of useful drugs, particularly insulin in diabetes mellitus, is essential in case of insulin deficiency. The aim of the present review was to introduce and examine different plasticizers and nanomaterials with potential applications for diabetic patients (such as selenium or gold-based nanoparticles that help the oral delivery of insulin) or plasticizers/nanomaterials acting similarly to EDCs in relation to the human and animal body, particularly glucose metabolism impairment such as diabetes mellitus (DM). Bisphenol A is a chemical used worldwide; however, the effect of exposure varies with regard to the source, environment, time of exposure and the age of the organism. Daily exposure is mostly related to food and drinks stored in polycarbonate plastics. However, exposure may also be through the skin or through the maternal placenta or breast milk which are risk factors for the fetus and for the newborn. It exerts an estrogen-like profile, but it also induces insulin resistance by impairing peripheral insulin receptors or it decreases insulin secretion by acting at the level of insulin-secreting pancreatic ß-cells. Phthalates, compounds of flexible plastics, act as EDCs via their human metabolites such as diethyl phthalate and derivative monoethyl phthalate. Their role in inducing gestational DM and weight gain/obesity during pregnancy has been showcased. The vast field of plasticizers and nanomolecules acting as endocrine disruptors is widely linked to clinical aspects of DM, a serious condition with a major population impact. The importance of understanding and using these agents and applications is reflected in saving numerous human lives.

Correlations between periodontal indices and osteoporosis.

In the pathogenesis of chronic periodontitis, there are general systemic factors which play a major role, such as osteoporosis, with menopause as the most common etiological factor, and other pathological determining conditions for osteoporosis as well (ovary, thyroid and malignant tumors). The aim of the present study was to assess the correlations between periodontal indices and osteoporosis. The study was performed on 35 patients with periodontal disease aged between 45 and 79 years. These patients were divided into two groups: a study group with osteoporosis and periodontal disease (n=25) and a control group with periodontal disease (n=10) only. The periodontal assessment included community periodontal index (CPI), gingival inflammation index (GI), plaque index (PI), body mass index (BMI), bone mineral density (BMD), tooth mobility and tooth loss. Osteoporosis was assessed by dual-energy X-ray absorptiometry. Results were statistically analyzed with Microsoft Excel software and XLSTAT. The results showed that patients in the study group had higher values of periodontal indices, and a highly significant inverse correlation was observed between the CPI and the tooth loss. Inverse correlations between BMI and tooth mobility, as well as BMI and CPI were determined for the study group. In conclusion, the positive association between BMD and GI shows that the gingival index can be a predictive factor in the occurrence of osteoporosis.

Intraoral Scanners in Orthodontics: A Critical Review.

BACKGROUND: The use of digital technology has exponentially increased over recent years. Intraoral scanners, especially, have gained traction within orthodontics. The objective of the present review is to investigate the available evidence to create an up-to-date presentation of various clinical aspects of intraoral scanners in orthodontics. METHODS: Search without restrictions in seven databases (Pubmed, CENTRAL, Cochrane Reviews, Scopus, Web of Science, Clinical Trials, Proquest) since inception, and hand searching until October 2020, were conducted. RESULTS: The majority of studies were either cross-over or parallel group studies. The accuracy and reproducibility of intraoral scanners, in comparison to conventional methods, were investigated in several studies, with controversial results. The duration of the procedure did not report any clear outcome in favor of any method. Patients seem to prefer intraoral scanning, even though numerous studies point out the importance of operators' experience and skills. CONCLUSIONS: Despite the innovations that intraoral scanners have brought in orthodontic clinical practice, there are still some challenges and limitations in their use. The majority of existing limitations may be overcome with experience and good clinical skills. More high-quality studies need to be conducted so that clinicians can have a clear image of this new technology.

A pilot study on the effectiveness of a 2-year school-based oral health educational programme using experiential learning among adolescents.

OBJECTIVE: The aim of the present study was to assess the influence of a school-based experiential education programme on oral health status, knowledge and behaviour among a group of schoolchildren in Bucharest. MATERIALS AND METHODS: The study was part of an Erasmus+ project that focused on oral health promotion in schools and covered a 2-year period. Data were collected from 120 teenagers from three schools in Bucharest, Romania. At baseline, all subjects were clinically examined and received a questionnaire. They were split into two groups at baseline: a test group with 76 schoolchildren and a control group with 44 schoolchildren. The schoolchildren included in the test group received three experiential lessons. After every lesson, they filled in the same questionnaire. At the end, all subjects were clinically examined again. RESULTS: The prevalence of dental caries was increased in the control group by 8.58% (N = 3, P = 0.31) and decreased in the test group by 1.64% (N = 1, P = 0.8). Regarding incipient carious lesions, a higher decrease was observed in the test group (D1-2 S: 0.78 vs 0.63, P = 0.867). There was a statistically significant plaque index decrease in the test group (1.32 vs 1.12; P = 0.01) and an increase in the control group (1.15 vs 1.79; P = 0.0001). More children from the test group (N = 5, 7.9%, P = 0.225) adopted twice-daily tooth brushing compared to the control group (N = 1, 2.9%, P = 0.52). CONCLUSIONS: In the group studied, the oral health programme had positive effects on oral health status, oral health knowledge and behaviour among adolescents.

The moral status of cerebral organoids.

Organoids are 3D biological structures constructed from stem cells in vitro. They partially mimic the function of real organs. Although the number of articles detailing this technology has increased in recent years, papers debating their ethical issues are few. In addition, many of such articles outline a mere summary of potential ethical concerns associated with organoids, although some have focused on consciousness assessment or organoid use in cystic fibrosis treatment. This article seeks to evaluate the moral status of cerebral organoids and to determine under which conditions their use should be allowed from a bioethical standpoint. We will present an overview of recent steps in developing highly advanced cerebral organoids, followed by an analysis of their ethics based on three factors: human origin, a specific biological threshold (which, once crossed, grants an entity moral status), and the potential to generate human beings. We will also make practical recommendations for researchers working in this biological field.

Incidence of the middle mesial canals in mandibular permanent molars in a Romanian population by cone-beam computed tomography.

INTRODUCTION: Untreated middle mesial canals (MMCs) of mandibular permanent molars can result in endodontic treatment failure. AIM: The aim of this retrospective study was to investigate the incidence of MMC of mandibular molars in a Romanian population. PATIENTS, MATERIALS AND METHODS: In total, there were evaluated 144 mandibular first permanent molars and 140 mandibular second permanent molars by using cone-beam computed tomography (CBCT) scans. RESULTS: The MMC was identified in 5.67% of mandibular first permanent molars, respectively in 4.28% of mandibular second permanent molars. The male∕female ratio of MMC presence was 1:3 of mandibular first molars and inverted for mandibular second molars (5:1). The presence of MMC in mandibular first molars was associated in all cases of our study with a second distal canal, unlike the mandibular second molars where no second distal canal was associated with a MMC. CONCLUSIONS: In Romanian population, the MMC of mandibular first molars, when present, is commonly associated with a second distal canal, unlike the mandibular second molars where the occurrence of a MMC was associated with only one distal canal. When performing the preoperative evaluation, it has also to be considered the patient gender, since the male∕female ratio of MMC was 1:3 in mandibular first molars and 5:1 in mandibular second molars.

The effect of dental pulp-capping materials on hard-tissue barrier formation: A systematic review and meta-analysis.

BACKGROUND: The authors of this systematic review aimed to compare the effects of pulp-capping materials on hard-tissue barrier formation using histologic assessments. TYPE OF STUDIES REVIEWED: The authors included randomized controlled trials and controlled clinical trials in humans, with vital therapies performed on healthy permanent teeth undergoing experimental mechanical pulp exposures. They searched electronically in the PubMed, Cochrane, Embase, and Summon databases and carried out a manual search. Twenty-seven full-text articles were eligible for inclusion in the systematic review. After data extraction, the authors performed 2 sets of meta-analyses with odds ratios (OR) and their 95% confidence intervals (CI) on 22 studies. Ten studies compared mineral trioxide aggregate (MTA) with calcium hydroxide (CH), and 12 compared bonding agents with CH. The authors assessed bias by means of Cochrane Collaboration's tool for assessing risk, funnel plots, and Harbord test. RESULTS: The use of MTA was associated with a higher rate of hard-tissue barrier formation than CH. The OR comparing the 2 groups was 2.45 (95% CI, 1.39 to 4.29; P = .002). Use of bonding agents was associated with a lower rate of hard-tissue barrier formation than CH. The OR comparing the 2 groups was 0.02 (95% CI, 0.01 to 0.05; P < .001). CONCLUSIONS AND PRACTICAL IMPLICATIONS: The results suggest that MTA and CH have positive effects on hard-tissue barrier formation. On the basis of the evidence, the authors conclude that MTA has better effects than CH regarding dental pulp protection in the capping of mechanical pulp exposures. Conversely, bonding agents are inferior to CH.

A rare case diagnosed as dentin dysplasia type II.

According to their phenotypic features, the hereditary dentin defects in humans are categorized in two major classes: dentinogenesis imperfecta and dentin dysplasia. At its turn, the dentin dysplasia is subdivided in dentin dysplasia type I and dentin dysplasia type II, a milder clinical manifestation of the condition. Here we report the clinical and radiographic findings of dentin dysplasia type II in two members of a family, a young adult female and her mother. Except a mild shade change of the incisal margins in upper central incisors and left upper canine of the daughter no abnormal occlusal wear or crown shape change of the teeth were disclosed in both patients. However, confluent large pulp stones in the thistle-tube shaped pulp chambers and pulpal obliteration were a common finding. The condition was diagnosed as dentin dysplasia type II.

GSK-3 Inhibitors and Tooth Repair: An Ethical Analysis.

Tideglusib®, a GSK-3 inhibitor, was initially tested for the treatment of Alzheimer's disease. However, a recent report has suggested its potential off-label use for the treatment of dental cavities. Even if this effect is not yet confirmed, this off-label use can have significant public/dental health consequences, mainly because of the large number of patients with cavities. The purpose of this mini-review is to perform an ethical analysis of the use of Tideglusib in dentistry. The ethical analysis identified three main areas in which ethical breaches could be significant: 1) respect for the autonomy of the patient, 2) issues raised by horizontal shifts in the translational research process, and 3) the conflict between dental beneficence and general non-maleficence. In conclusion, the use of Tideglusib in dentistry should respect the same strict ethical and regulatory criteria from clinical medicine. A translation of the potential risks should be done only after large-scale, phase-III/IV clinical trials, explicitly designed to test the usefulness of this drug in dental medicine.

Middle mesial canal of the permanent mandibular first molars: an anatomical challenge directly related to the outcome of endodontic treatment.

To effectively clean and shape the mandibular permanent first molars it is mandatory to understand in detail their complex internal anatomy. The middle mesial canal is an additional canal located between the usual mesiobuccal and mesiolingual canals in the mesial root of mandibular first molars. The incidence of the middle mesial canal, its relationship with main canals of the mesial root and the possibility for it to be negotiated is an important practical issue in endodontics. To identify the presence of this canal is mandatory. Accordingly, a modified endodontic access, the use of the operating microscope and periapical radiographs in two different horizontal projections are indicated to enhance the long-term favorable outcome of the endodontic treatment.