O emprego da moldagem digital na prática odontológica - relato de caso / The use of digital molding in dental practice ­ case report

O avanço da tecnologia de digitalização de imagens e desenvolvimento de dispositivos de fresagem possibilitaram a otimização de diversos processos na Odontologia. O emprego do escaneamento intraoral e do sistema CAD-CAM (CAD - Computer Aided Design; CAM - Computer Aided Manufacturing) aprimorou a realização de reabilitações protéticas, permitindo a obtenção de peças de alta qualidade em tempo reduzido. O objetivo deste trabalho é relatar um caso de reabilitação de um incisivo central inferior a partir de escaneamento intraoral, com scanner Omnicam (DentsplySirona Charlotte, NC, EUA) e aplicação do sistema CAD-CAM.

The advancement of image digitization technology and the development of milling devices have made it possible to optimize various processes in Dentistry. The use of intraoral scanning and the CAD-CAM system (CAD - Computer Aided Design; CAM - Computer Aided Manufacturing) has improved the performance of prosthetic rehabilitations, allowing the obtaining of high quality parts in a reduced time. The objective of this work is to report a case of rehabilitation of a lower central incisor using intraoral scanning, with an Omnicam scanner (Dentsply Sirona) and application of the CAD-CAM system.

Investigação ex vivo do diâmetro anatômico do canal mesiopalatino de primeiros molares superiores humanos / Ex vivo investigation of the anatomical diameter of the mesiopalatal canal of human maxillary first molars

Objetivou-se investigar ex vivo o diâmetro anatômico e conicidade do canal mesiopalatino de primeiros molares superiores. Para tanto, trinta e três primeiros molares superiores humanos foram acessados, explorados para confirmação da existência do canal mesiopalatino, identificados, suas raízes mesiovestibulares seccionadas transversalmente em três níveis e, então, os fragmentos foram fotografados com microscópio digital, que permitiu a realização das determinações dos diâmetros anatômicos deste canal em cada amostra. Os resultados foram calculados em função dos valores médios e de desvio padrão dos diâmetros em cada nível, obtendo-se respectivamente 0,20 mm e ±0,09 mm (nível cervical), 0,20 mm e ±0,08 mm (nível médio) e 0,17 mm e ±0,06 mm (nível apical). Nas condições deste estudo, de acordo com caráter atrésico e baixa conicidade do conduto mesiopalatino, sugere-se a necessidade de uso de instrumentos de diâmetro de ponta mínimo de 0,25 mm e conicidade 0,03 para o seu preparo.

The aim was to investigate ex vivo the anatomical diameter and taper of the mesiopalatine canal of maxillary first molars. To this end, thirty-three human maxillary first molars were accessed, explored to confirm the existence of the mesiopalatine canal, identified, their mesiobuccal roots transversely sectioned at three levels and then the fragments were photographed using a digital microscope, which allowed the anatomical diameters of this canal to be determined in each sample. The results were calculated according to the mean and standard deviation values of the diameters at each level, obtaining 0.20 mm and ±0.09 mm (cervical level), 0.20 mm and ±0.08 mm (middle level) and 0.17 mm and ±0.06 mm (apical level) respectively. Under the conditions of this study, given the atresic nature and low taper of the mesiopalatine canal, it is suggested that instruments with a minimum tip diameter of 0.25 mm and a taper of 0.03 should be used for its preparation.

Percepção de aprendizagem on-line na disciplina de biomateriais / Perception of online learning in the biomaterials course

Com as universidades fechadas e a implementação do Ensino Remoto Emergencial, as atividades curriculares ocorreram através de plataformas digitais. O objetivo do presente trabalho foi avaliar a percepção de aprendizagem on-line na disciplina de Biomateriais da Faculdade de Odontologia da Universidade Federal Fluminense no período da pandemia. O questionário COLLES (Constructivist OnLine Learning Environment Survey) foi enviado individualmente por e-mail aos cinquenta alunos, apresentando 24 declarações divididas em seis quesitos: relevância, reflexão crítica, interatividade, apoio dos tutores, apoio entre os colegas e compreensão; e para cada declaração cinco opções de resposta: quase sempre, frequentemente, algumas vezes, raramente e quase nunca. Quarenta e um alunos responderam. A soma das médias obtidas em quase sempre e frequentemente foi de 87,2% para relevância, 70% para reflexão crítica, 33,9% para interatividade, 47,6% para apoio dos tutores, 44,2% para apoio dos colegas e 89,5% para compreensão. Concluiu-se que a relevância, a reflexão crítica e a compreensão apresentaram melhores resultados, enquanto a interatividade, o apoio entre os colegas e o apoio dos tutores demonstraram necessidade de aprimoramento. E apesar das limitações do ERE, a avaliação positiva dos alunos evidenciou esta modalidade de educação on-line como uma solução plausível.

With universities closed and the implementation of Emergency Remote Teaching, curricular activities took place through digital platforms. The objective of this study was to assess the perception of online learning in the Biomaterials course at the Dental School of the Federal Fluminense University during the pandemic. The COLLES questionnaire (Constructivist OnLine Learning Environment Survey) was individually sent via email to fifty students, presenting 24 statements divided into six aspects: relevance, critical reflection, interactivity, tutor support, peer support, and comprehension. For each statement, there were five response options: almost always, often, sometimes, rarely, and almost never. Forty-one students responded. The sum of the averages obtained for almost always and often was 87.2% for relevance, 70% for critical reflection, 33.9% for interactivity, 47.6% for tutor support, 44.2% for peer support, and 89.5% for comprehension. It was concluded that relevance, critical reflection, and comprehension showed better results, while interactivity, peer support, and tutor support demonstrated a need for improvement. Despite the limitations of Emergency Remote Teaching, the positive evaluation from the students highlighted this mode of online education as a plausible solution.

Sedação consciente com óxido nitroso em clínica odontológica: principais indicações e segurança / Concious sedation with nitrous oxide in dental clinics: main indications and safety

A ansiedade desempenha um papel significativo na experiência de tratamentos odontológicos e pode resultar em evasão por parte dos pacientes. Isso é especialmente relevante para grupos como pacientes pediátricos e aqueles com necessidades especiais, que muitas vezes requerem técnicas de controle de comportamento ou sedação devido à ansiedade. No entanto, a ansiedade não deve ser negligenciada mesmo em pacientes sem odontofobia grave, pois está relacionada à percepção da dor durante os procedimentos odontológicos. A sedação consciente com óxido nitroso surge como uma alternativa valiosa para reduzir a ansiedade e melhorar o conforto do paciente. Ao contrário dos benzodiazepínicos e da anestesia geral, o óxido nitroso atua no sistema nervoso de uma forma que deprime levemente o córtex cerebral, sem afetar o centro respiratório. Isso permite o uso de concentrações subanestésicas do gás, administradas com oxigênio por meio de uma máscara nasal. O óxido nitroso é de rápida ação, pouco solúvel e tem um período de recuperação breve, permitindo que os pacientes retornem rapidamente às atividades normais. Este estudo, uma revisão de literatura, explora o mecanismo de ação do óxido nitroso, suas indicações na prática odontológica e examina possíveis riscos e contraindicações associados ao seu uso. Em resumo, a sedação consciente com óxido nitroso se mostra como uma opção promissora para aliviar a ansiedade e melhorar a experiência de tratamentos odontológicos, beneficiando uma ampla gama de pacientes, não apenas aqueles com fobias graves.

Anxiety, in an outpatient dental environment, plays a fundamental role in pain and discomfort expectation, resulting in increase of treatment evasion. The groups that present greater difficulty in cooperation are children and special needs patients, with behavioral control and sedation being often necessary. Nevertheless, literature emphasizes that anxiety must be evaluated as a critical stage and its management done not only in patients with elevated anxiety levels, but being crucial on pain control of every dental patient, since higher grades of restlessness equals higher pain perception. It is known that the use of nitrous oxide in conscious sedation proves to be an useful tool on reducing anxiety and enabling comfortable interventions, indicating that it is an alternative to the use of benzodiazepines and general anesthesia. The drug acts on the nervous system, promoting a slight depression of the cerebral cortex and, unlike benzodiazepines, which act at the medulla level, it does not depress the respiratory center. The technique uses sub-anesthetic concentrations of nitrous oxide delivered with oxygen through a nasal mask. Nitrous oxide is poorly soluble and has a rapid onset of action, being therefore associated with a rapid recovery period. The duration of sedation is controlled and the patient can quickly return to normal activities. This paper is a narrative review with the objective of exploring the mechanism of action of this gas, evaluating its indications for use in dental clinic and verifying possible risks and contraindications.

Exploring the potential of tomato juice (Solanum lycopersicum L.) patch for tooth bleaching.

Background: Tomato, renowned for its tooth-whitening properties due to its hydrogen peroxide and peroxidase enzyme content, requires formulation for enhanced applicability. This study assessed the dental whitening efficacy of a patch containing tomato juice as the active ingredient. Methods: Tomato juice patches were formulated at concentrations of 55%, 60%, and 65%. A control group (C) containing a 12% hydrogen peroxide patch was also included. A matrix layer of the patches was prepared using the solvent casting method at 40 for 18 h, with TegadermTM applied as the backing layer. For the dental whitening procedure, each group of patches was applied to the labial surface of anterior stained teeth (n=6/group) for 3 h, repeated 14 times. Tooth brightness was evaluated qualitatively and quantitatively using digital dental photo CIEL*a*b* analysis. Meanwhile, enamel surfaces were examined under a scanning electron microscope (SEM). Repeated-measures analysis of variance (ANOVA) was employed for statistical analysis. Results: The application of tomato juice patches led to enhanced tooth brightness. The patch containing 65% tomato juice significantly improved stained tooth brightness (P<0.05). SEM analysis revealed less enamel erosion with the 65% tomato juice patch compared to the 12% hydrogen peroxide patch. Conclusion: Tomato juice patches effectively increased tooth brightness while minimizing demineralization. Further research is needed to optimize formulation and explore its potential.

Clinical assessment of monolithic zirconia crowns fabricated using an intraoral scanner.

Background: This in vivo study assessed the accuracy of single-tooth monolithic zirconia crowns made using an intraoral scanner (IOS) and computer-aided design/computer-aided manufacturing (CAD/CAM) technology. Methods: Thirty patients requiring single posterior crowns were selected. The teeth were prepared with a deep chamfer finish line with a 1-mm extension subgingivally and a 1-mm reduction in all surfaces by one prosthodontist. The gingival margins were retracted using a gingival retraction paste before making impressions using a Trios scanner. All the digital impression files were sent to one laboratory using the dental designer software (3Shape, Copenhagen, Denmark). After completing the milling and sintering processes, the crowns were dyed and glazed. After removing the temporary crown, the qualitative assessment of proximal contacts of definitive monolithic zirconia crowns was performed according to the CDA criteria. Data were analyzed with Friedman's two-way analysis and independent t-test at α=0.05. Results: The difference in axial and total gaps between premolar and molar teeth was not significant; however, the mean marginal gap of molars was higher than that of the premolars (P=0.043). Furthermore, the comparison of the axial, total, and marginal gaps between the upper and lower jaws showed no significant difference (P>0.05). The distribution of occlusal and proximal contacts indicated 60% and 66.7% proper contacts and no contacts in 6.7% and 10% of cases, respectively. Conclusion: Using IOSs could result in accurate monolithic zirconia crowns in terms of adaptation. Also, most occlusal and proximal contacts did not need any adjustments.

Effect of postoperative 660-nm low-level laser therapy on the radiographic crestal bone loss of fresh-socket dental implants.

Background: Although the benefits of low-level laser therapy (LLLT) in soft tissue healing have been demonstrated, the effects of laser on bone have remained controversial. This study investigated the impact of postoperative 660-nm LLLT on the radiographic crestal bone loss of fresh-socket dental implants. Methods: Thirty patients referred to the Department of Oral and Maxillofacial Surgery for tooth extraction and placement of fresh-socket implants were selected and assigned to two groups: laser (intervention) and no-laser (control) groups. Immediately after tooth extraction, the implant was inserted into the tooth socket. 660-nm LLLT was immediately started after surgery and was repeated three times per week for two weeks. Bone quantification at the implant site was assessed using periapical intraoral radiographs and computerized software immediately after surgery and after six months. Results: This study showed a statistically significant difference in mean bone resorption between the mesial and distal aspects of the two groups, with lower bone resorption in the laser group compared to the no-laser group. Conclusion: The results of this study suggest that LLLT can effectively reduce bone resorption in fresh-socket implant placement. This might indicate the positive effect of LLLT on bone resorption reduction.

Multiaxial fatigue life assessment of dental implants.

As screwed joints, dental restorations may suffer mechanical failures such as screw loosening and implant or prosthetic screw failure due to fatigue. This work is focused on the failure of the implant and develops a numerical methodology to predict its fatigue life under cyclic loading conditions. This methodology is based on the combination of Critical Plane Methods and the Theory of Critical Distances to account for stress multiaxiality and notch effects. The obtained predictions were validated experimentally, which can be used to identify the main geometrical, assembly and operational factors affecting the fatigue behavior of dental implants. As a result, a powerful and efficient design tool for fatigue life prediction of dental implants is presented. This methodology complements a previously presented one focused on the fatigue life prediction of the prosthetic screw, thereby, offering now a complete design tool package regardless the critical component of the dental restoration, predicting accurately the fatigue response of the restoration, with no need for long-term fatigue test campaigns. This is a pioneering work since no other fatigue design methodology for dental implants with such a solid foundation and experimental validation has been published to date.

Oral diseases and systemic conditions: correlation analyses from the Colombian national health records between 2016 and 2023.

Introduction: Prevalence of oral, metabolic, circulatory, and nutritional diseases has tended to increase globally. As these diseases have common contributing factors, such as unhealthy diets, evaluating their epidemiological trends and the relation between them is relevant. In Colombia, the Ministry of Health records the frequency of consultation for these diseases through the Integrated Social Protection Information System. It facilitates the evaluation of their epidemiological behavior at the population level. Aim: To analyze and correlate the burden of oral diseases (caries and periodontitis) with respect to nutritional, circulatory and metabolic pathologies, as well as their relationships with socioeconomic indices in Colombian regions from 2016 to 2023. Methods: This study analyzes retrospective data collected between 2016 and 2023 by the National Health Registry in Colombia (SISPRO) according to the ICD-10. Sociodemographic data and the number of disease consultations were extracted. The number of consultations for oral diseases was correlated with systemic pathologies, socioeconomic indices through the Spearman test. Associations were explored via multiple linear regressions. A Principal Component Analyses (PCA) was conducted to identify patterns between socioeconomic, oral and systemic disease variables, as well as to reduce the complexity of the analysis by creating clusters that capture the greatest possible variability in the data. Results: The average number of consultations per biennium was 24.550.435 being the highest number for 2018-2019. The highest percentage of consultations was related to extensive caries, followed by chronic gingivitis. Moreover, consultations for oral diseases were found to correlate with systemic pathologies. All socioeconomic indices were associated with caries and/or periodontal diseases. This study is the first in Colombia that uses national data on diagnoses assigned to medical and dental consultations. PCA revealed a clustering pattern of pathologies suggesting that they are highly associated one to each other. Conclusion: Correlations between consultations for oral and systemic diseases stratified by life cycle and socioeconomic indices highlight the importance of conducting epidemiological and public health characterizations and their associations. Identifying these factors is imperative in the prevention and management of both diseases.

Evolutionary palaeoecology of European rhinocerotids across the Oligocene-Miocene transition.

The Oligocene-Miocene transition witnessed great environmental and faunal changes, spanning from late Oligocene to early Miocene (MP28-MN3). Its drivers and consequences on mammals are, however, poorly understood. Rhinocerotoids are among the most affected taxa, reflected by great taxonomical and morphological changes. However, potential associated changes in ecology have not been explored. Here, we investigated the palaeoecology of 10 rhinocerotid species coming from 15 localities across Western Europe and ranging from MP28 to MN3. We explored evolutionary trends for diet, physiology and habitat via dental wear, hypoplasia, body mass and stable isotopy. All rhinocerotids studied were C3 feeders, whether browsing or mixed-feeding, but clear dietary differences were observed at some localities and between Oligocene and Miocene rhinocerotids. The prevalence of hypoplasia was low (less than 10%) to moderate (less than 20%), but there were great differences by loci, species and localities. Body mass covaried with hypoplasia prevalence, suggesting that larger species might be more susceptible to stresses and environmental changes. We reconstructed similar warm conditions at all localities except Gaimersheim, but found greater variations in precipitation. Indeed, a clear shift in δ13C values was noticed at the end of the Oligocene, consistent with climatic and vegetation changes reported at that time.

Energy-dispersive Laue diffraction analysis of the influence of statherin and histatin on the crystallographic texture during human dental enamel demineralization.

Energy-dispersive Laue diffraction (EDLD) is a powerful method to obtain position-resolved texture information in inhomogeneous biological samples without the need for sample rotation. This study employs EDLD texture scanning to investigate the impact of two salivary peptides, statherin (STN) and histatin-1 (HTN) 21 N-terminal peptides (STN21 and HTN21), on the crystallographic structure of dental enamel. These proteins are known to play crucial roles in dental caries progression. Three healthy incisors were randomly assigned to three groups: artificially demineralized, demineralized after HTN21 peptide pre-treatment and demineralized after STN21 peptide pre-treatment. To understand the micro-scale structure of the enamel, each specimen was scanned from the enamel surface to a depth of 250 µm using microbeam EDLD. Via the use of a white beam and a pixelated detector, where each pixel functions as a spectrometer, pole figures were obtained in a single exposure at each measurement point. The results revealed distinct orientations of hydroxyapatite crystallites and notable texture variation in the peptide-treated demineralized samples compared with the demineralized control. Specifically, the peptide-treated demineralized samples exhibited up to three orientation populations, in contrast to the demineralized control which displayed only a single orientation population. The texture index of the demineralized control (2.00 ± 0.21) was found to be lower than that of either the STN21 (2.32 ± 0.20) or the HTN21 (2.90 ± 0.46) treated samples. Hence, texture scanning with EDLD gives new insights into dental enamel crystallite orientation and links the present understanding of enamel demineralization to the underlying crystalline texture. For the first time, the feasibility of EDLD texture measurements for quantitative texture evaluation in demineralized dental enamel samples is demonstrated.

Opinions of Dental Technologists in Nigeria on Quality of Work Authorization for Removable Dental Prosthesis.

BACKGROUND: When fabricating a removable dental prosthesis, clear and sufficient communication between the dentist and dental laboratory technologist is crucial to ensure a successful outcome. OBJECTIVES: To evaluate the quality of communication between dentists and dental laboratories via work authorizations for the fabrication of removable prosthesis across the six geographical zones in Nigeria. MATERIALS AND METHODS: A cross-sectional descriptive study was conducted among dental technologists in Nigeria. A 22- item, online survey questionnaire was sent to all the participants through their respective states and the National Dental Technologist Association across the six geographical zones in the country. Data obtained were analyzed. Association between variables was carried out using the Chi-square test. Binary logistic regression was used to predict group membership. RESULTS: A total of 62 dental technologists participated in this study; the highest percentage of respondents, 29.1% was from South West. Only 21% of the respondents reported that they received work authorizations with adequate information to complete a denture setup most time. Also, 16.1% of the technologists received casts with adequate rest seats and guide planes prepared on the abutment teeth. Eighteen respondents (29%) stated that the authorization card does not contain all the required information. Fabrication of more than 7cast RPDs could be used to predict dental technologists who hold a positive view on the provision of quality work authorization by dentists. (P≤0.05).

CONTEXTE: Lors de la fabrication d'une prothèse dentaire amovible, une communication claire et suffisante entre le dentiste et le technologue de laboratoire dentaire est cruciale pour garantir un résultat satisfaisant. OBJECTIFS: Évaluer la qualité de la communication entre les dentistes et les laboratoires dentaires par le biais d'autorisations de travail pour la fabrication de prothèses amovibles dans les six zones géographiques du Nigeria. MATÉRIEL ET MÉTHODES: Une étude descriptive transversale a été menée auprès des prothésistes dentaires au Nigeria. Un questionnaire d'enquête en ligne de 22 questions a été envoyé à tous les participants par l'intermédiaire de leurs États respectifs et de l'Association nationale des technologues dentaires dans les six zones géographiques du pays. Les données obtenues ont été analysées. L'association entre les variables a été réalisée à l'aide du test du chi carré. La régression logistique binaire a été utilisée pour prédire l'appartenance à un groupe. RÉSULTATS: Au total, 62 technologues dentaires ont participé à cette étude ; le pourcentage le plus élevé de répondants, soit 29,1 %, provenait du Sud-Ouest. Seulement 21% des répondants ont déclaré avoir reçu des autorisations de travail avec des informations adéquates pour réaliser un montage de prothèse dentaire la plupart du temps. De plus, 16,1 % des technologues ont reçu des moulages avec des sièges de repos et des plans de guidage adéquats préparés sur les dents piliers. Dix-huit répondants (29 %) ont déclaré que la carte d'autorisation ne contenait pas toutes les informations requises. La fabrication de plus de sept prothèses dentaires de recouvrement pourrait être utilisée pour prédire les technologues dentaires qui ont une opinion positive sur la fourniture d'une autorisation de travail de qualité par les dentistes. (P≤0.05). CONCLUSIONS: La qualité de l'autorisation de travail pour la fabrication de prothèses dentaires amovibles était moins qu'adéquate dans les six zones géographiques du Nigeria. Cela laisse généralement une grande partie de la prise de décision aux technologues de laboratoire dentaire. MOTS-CLÉS: Technologue dentaire, prothèse dentaire amovible, autorisation de travail.

Altered Passive Eruption among Patients Visiting Dental Outpatient Department in a Tertiary Care Center: A Descriptive Cross-sectional Study.

INTRODUCTION: The eruption of teeth is considered to be a continuous phenomenon. Two types of eruption are possible namely, active and passive eruption. Failure in passive eruption (by the apical movement of gingiva from the enamel surface) generally results in a clinical condition known as altered passive eruption. It can result in the shortened crown height of a tooth and an esthetically unpleasant situation i.e., excessive gingival display or gummy smile. The main motto of this study was to find out the prevalence of altered passive eruption and associated gingival biotypes in adult patients visiting for dental treatment in tertiary centers along with strategically placed outreach centers. METHODS: A descriptive cross-sectional study was done in the Department of Dentistry, Dhulikhel Hospital, and four outreach centers of the same hospital. The study was conducted from October 2022 to April 2023 after obtaining the ethical approval. Convenience sampling was done. Point estimate and 95% Confidence Interval were calculated. RESULTS: Among 165 patients, the prevalence of altered passive eruption was 21 (12.72%) (7.62-17.78 at 95% Confidence Interval). Furthermore, among 21 patients, the altered passive eruption was seen in the thick biotype patients in 16 (76.19%) and thin biotype patients in 5 (23.81%). CONCLUSIONS: The prevalence of altered passive eruption appeared to be equivalent when compared with the previous studies.

The dentition of a new adult Neanderthal individual from Grotte Mandrin, France.

Grotte Mandrin is located in the middle Rhône River Valley, in Mediterranean France, and has yielded 11 Pleistocene archeological and paleoanthropological layers (ranging from the oldest layer J to the youngest layer B) dating from Marine Isotope Stage (MIS) 5 to MIS 3. We report here the nearly complete dentition of an adult Neanderthal individual, nicknamed 'Thorin,' associated to the last phase of the Post-Neronian II, in layer B2 (∼44.50-42.25 ka). A previous paleogenetic analysis revealed that Thorin is a male individual and that he shows a deep genetic divergence with other penecontemporaneous Neanderthals from western Europe that possibly occurred ∼105 ka. The 31 teeth of Thorin (including two distomolars) are described and analyzed using microcomputed tomography imaging and are compared with other Neanderthals and modern humans. Based on direct observation and measurements on the fossil remains, and using microtomographic imaging, tooth wear, nonmetric characters, crown dimensions, and dental tissue proportions were investigated, and the shape of the enamel-dentine junction of the M2, M2, and M3 was analyzed by geometric morphometrics. Our results indicate that Thorin's teeth show dental characteristics typical of MIS 5-3 Neanderthals. It is also the first time that the presence of two distomolars is reported in a Neanderthal individual, a trait that is rare among modern human populations. Combined with the genetic peculiarities of this individual, the results of the present study imply either a process of morphological convergence among the latest Neanderthal groups or an underestimation of the genetic variability of recent Neanderthal groups.

Modulation of regenerative responses by retinoic and ascorbic acids in human apical papilla cells.

OBJECTIVE: This study investigated the bioactive effects of retinoic acid and ascorbic acid on hSCAPs in vitro. DESIGN: Cells were obtained from human third molars (n=4) and characterized for mesenchymal stem cell markers by flow cytometry. The experimental groups: control (α-MEM); vehicle control group (α-MEM + 0.17 % DMSO); retinoic acid 0.1, 1, and 10 µM; and ascorbic acid 3, 30, and 300 µM (n=8) were tested for cell viability (alamarBlue; 1, 3, and 7 days), total collagen synthesis (Sirius Red; 1 and 7 days), mineralized matrix formation (Alizarin red; 14 days), and the regulation of gene expression related to mineralization (ALPL and DSPP), cell migration (ITGAV and CXCL12) angiogenesis (VEGFA) and collagen synthesis (COL1A1 and COL3A1; RT-qPCR) on 1 and 7 days. ACTB and GAPDH were used as reference genes. Data were analyzed by ANOVA and complementary tests at a 5 % significance level. RESULTS: Ascorbic acid 300 µM increased viability, and retinoic acid reduced it dose-dependently. Retinoic acid 0.1 µM and ascorbic acid 30 and 300 µM increased mineralized matrix formation and total collagen synthesis, and retinoic acid 10 µM decreased. On day 1, 0.1 µM retinoic acid upregulated the gene expression of COL1A1, COL3A1, VEGFA, CXCL12, ALPL, DSPP e ITGAV, and 300 µM ascorbic acid upregulated COL1A1, COL3A1 and DSPP. However, on day 7, retinoic acid downregulated ALPL, COL3A1, CXCL12, and VEGFA and downregulated ITGAV and VEGFA. CONCLUSION: Retinoic acid 0.1 µM and ascorbic acid 300 µM biostimulated hSCAPs to differentiate into pro-regenerative phenotypes with potential application for REPs.

Inflammatory and adhesion profile of gingival fibroblasts to lithium disilicate ceramic surfaces.

OBJECTIVES: Lithium disilicate (LS) ceramic emerges as a compelling option for customized implant abutments. However, ensuring its safety and reliability requires clarification on key aspects, notably its impact on inflammation and potential for cell adhesion. This study delves into these considerations, examining the influence of LS ceramic on cytokine release and the transcriptional profile of human gingival fibroblasts (hGFs) in direct contact with various LS surfaces. METHODS: hGFs were cultured on LS disks featuring three distinct surfaces (unpolished, polished, and polished glaze), while titanium disks served as reference material and cells cultured directly on plates as controls. The surface of the disks was analyzed using a scanning electron microscope. The cell metabolism was analyzed by MTT test, cytokine release by MAGPIX and the expression of genes related to cell adhesion was evaluated by qPCR. RESULTS: The disks exhibited similar topography with smooth surfaces, except for the unpolished LS disks, which had an irregular surface. Contact with LS surfaces did not substantially reduce cell metabolism. Moreover, it generally decreased cytokine release compared to controls, particularly pro-inflammatory mediators like IL-1ß, IL-6, and TNF-α. Significantly increased expression of genes related to cell adhesion to LS was observed, comparable to titanium, the gold standard material for implant abutments. SIGNIFICANCE: This study unveils that LS ceramic not only fails to trigger pro-inflammatory cytokine release, but also significantly enhances gene expression associated with cell adhesion. These mechanisms are closely linked to gene pathways such as PTK2, SRC, MAPK1, and transcription factors ELK-1 and MYC. In summary, the findings underscore LS ceramic's potential as a biocompatible material for implant abutments, shedding light on its favorable inflammatory response and enhanced cell adhesion properties.

Undergraduate endodontic curricula across Canadian Dental Schools: A cross-sectional analysis.

INTRODUCTION: This study aimed to evaluate and assess the degree of uniformity in endodontics education at the undergraduate level among Canadian dental schools. The objective is to enhance Canadian dental education programs to meet societal oral health needs while incorporating advancements in the field of endodontics. METHODS: An online survey comprising 36 multiple-choice questions targeting the nature of endodontic teaching was conducted as our methodology. Participation was sought from directors of the undergraduate endodontics program at all ten Canadian dental schools in 2021 and 2022. RESULTS: A remarkable 100% response rate and the findings revealed a certain level of consistency among Canadian schools concerning pedagogical and assessment methods, as well as the endodontic topics taught to undergraduate students. However, notable variations were observed in the equipment and materials utilized. This study serves as a fundamental reference for identifying future modifications to the undergraduate endodontics curriculum in Canada.

Risk of Severe Early Childhood Caries over Time in Low-Income Preschoolers.

INTRODUCTION: Early childhood caries (ECC), and the progression to severe ECC (S-ECC), is a serious oral health issue, leading to acute pain, sepsis, tooth loss, and compromised quality of life. Although the association between sociodemographic factors and ECC has been widely discussed, it remains unclear whether the same association exists between inequality and S-ECC. OBJECTIVES: To investigate the impact of low income on the oral health of preschool children and explore any additional risk factors for developing ECC and S-ECC during follow-up. METHODS: The study used Taipei Child Development Screening Program data from 2014 to 2019. It included children aged 3 to 5 y who had more than 2 oral exams and completed baseline oral health questionnaires. Low-income children were matched 1:4 with controls by age and gender. Evaluation of ECC and S-ECC used the dmft index during follow-up exams. Generalized estimating equations (GEEs) assessed the impact of household income on ECC and S-ECC risk over time. RESULTS: Of the 895 participants, 179 were from low-income households. We revealed a significantly higher risk of developing S-ECC (adjusted odds ratio [aOR] 1.99; 95% confidence interval [CI] 1.25-3.17) in children from low-income households, with no significantly increased of risk of developing ECC. Children who consumed sugary beverages >4 times per week showed elevated risks of developing both ECC (aOR 1.77; 95% CI 1.07-2.94) and S-ECC (aOR 1.89; 95% CI 1.13-3.17). Protective factors included children with mothers with a college education (S-ECC: aOR 0.50; 95% CI 0.32-0.79). CONCLUSION: Children from low-income households have a significant risk of developing S-ECC compared with children from non-low-income households during follow-up. Factors contributing to this risk include lower maternal education, poor maternal oral health, and increased consumption of sugar-sweetened beverages. Policymakers should develop health measures to reduce the prevalence of ECC and S-ECC in children from low-income households whose mothers have lower educational levels and poor oral health. KNOWLEDGE TRANSFER STATEMENT: The results of this study highlight the significant S-ECC risk among preschool children from low-income households in Taipei, with other risk factors including higher consumption of sugar-sweetened beverages, lower maternal education, and poor maternal oral health. Policymakers can use our findings to develop targeted policy and behavioral interventions to reduce S-ECC in vulnerable populations.

Dental Implant placement in a patient with polycythemia vera: A case report.

Polycythemia vera is a malignant myeloproliferative neoplasm. It is characterized by the proliferation of all three major hematopoietic cells, including erythrocytes, leucocytes, and platelets. The resultant hypervolemia and hyperviscosity cause patients with polycythemia vera to be at risk of bleeding and thrombotic complications. This article reports a rare case in which a patient with preexisting polycythemia vera at a dental clinic underwent dental implant placement and provides the possibility of dental implant placement with an excellent outcome for patients with polycythemia vera.

Repairing Dehiscence Defects at Implant Sites using ß-Tricalcium Phosphate/Calcium Sulfate versus Xenograft Combined With Membrane: A Randomized Clinical Trial.

Guided bone regeneration (GBR) typically involves bone grafts and a membrane to enhance bone formation. Beta-tricalcium phosphate calcium sulfate (ß-TCP/CS) is a novel material with self-hardening and tissue growth inhibition properties and can potentially replace the need for a membrane. This study compares ß-TricalciumPhosphate/CalciumSulfate with deproteinized bovine bone mineral and a collagen membrane (DBBM/CM) to repair bone defects at implant sites over six months. Sixteen implant defects were divided into ß-TCP/CS (n = 8) and DBBM/CM (n = 8). The results showed no significant differences in vertical and horizontal defect fill in millimeters between ß-TCP/CS (2.87±1.25 and 2.37±1.06 mm., respectively) and DBBM/CM (3.5±0.92 and 2.87±1.12 mm. , respectively). Buccal bone thickness (BT) alterations at the implant platform levels (BT0) were similar for both materials. However, ß-TCP/CS exhibited greater bone alteration at the 2-mm level (BT2: -1.85 mm vs. -0.47 mm) and 4-mm level (BT4: -1.79 mm vs. 0.12 mm) apical to the implant platform compared to DBBM/CM. When assessing volume alteration, ß-TCP/CS showed a significantly greater reduction at the platform to the 2 mm level (-61.98% vs. -23.76%) than DBBM/CM. In conclusion, ß-TCP/CS demonstrated promise for treating buccal bone defects around implants but exhibited higher graft reduction. This suggests that while ß-TricalciumPhosphate/CalciumSulfate may offer clinical benefits, its potential for greater graft reduction should be considered. Further research and evaluation are warranted to fully understand the long-term implications of using ß-TCP/CS in guided bone regeneration procedures.