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Objective: The purpose of this study was to assess 6th year students' attitudes and perceptions towards problem-based learning sessions during their clinical internship. Methods: A cross-sectional study was conducted among undergraduate dental students at the hospital Farhat Hached Sousse in Tunisia from February to August 2023. Use questionnaires to survey students' attitudes and perceptions about problem-based learning sessions. Data were analyzed using SPSS 21. Results: 6th year dental students reported positive attitudes toward all programs, including self-directed learning, critical thinking, integrating fundamental concepts into clinical science, identifying knowledge gaps, and improving problem-solving skills. Conclusions: Most undergraduate students preferred PBL and felt it should be included in the curriculum along with other teaching methods.

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Aim: To determine the effect of ethylenediaminetetraacetic acid (EDTA), lactic acid and citric acid on root dentin microhardness. Materials and Methods: In this in vitro study, twenty freshly extracted anterior teeth were transversely sectioned at the level of cementoenamel junction. The middle third of each root is then horizontally sectioned into slices that are 4 mm thick to obtain a total of 20 dentin discs. Based on the chelating agent used, the samples were randomly divided into four groups- saline (control group), 17% EDTA, 20% lactic acid and 10% citric acid. Vicker’s indenter was used to test the microhardness of the dentin before and after treatment with the chelating agents for two minutes. Data was obtained and statistically evaluated using a one-way analysis of variance (ANOVA), paired – t test and Tukey’s post hoc test. Results: The microhardness values varied significantly among the groups. Citric acid and and lactic acid were less effective at reducing dentin microhardness. EDTA led to a higher reduction in microhardness. Conclusion: All the chelating solutions reduced the microhardness. Lactic acid showed less alteration in the hardness of root dentin than EDTA.

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Objective: To evaluate the quality of the services provided by the dental clinics of the Autonomous University of Baja California (UABC) Otay-Tijuana Campus using the Donabedian and SERVPERF methodologies to know strategies that allow improving the quality of care. Methodological design: A prospective cross-sectional study was carried out in a random sample of 1,315 surveys of patients who attended the clinics of the Tijuana Faculty of Dentistry of the UABC in the period 2023-1. To collect the information, the PERCACEL tool was used, developed using the Donabedian and SERVPERF methodologies, which consists of 4 sections: 1) Specifications of the clinic that provided the service and time in which the care was received, 2) General data of the respondent, 3) Perceptions of the care received and 4) User perception of the service provided. This survey was validated in the city of Puebla to be used in dental care clinics, obtaining a Cronbach's Alpha of 0.923 for the Donabedian instrument and 0.963 for the SERVPERF instrument. Results: The average of the evaluation obtained from the perception of quality through the SERVPERF model was 9.13, slightly higher than that obtained through the Donabedian model, which was 8.98, demonstrating that the quality of care provided by the university community is high without great variations.

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The aim of this study was to determine whether the intensity of preoperative pain was a predictive factor for the prevalence and intensity of postoperative pain, considering demographic and clinical variables. The study involved́ 80 teeth with pulpal or periapical pathologies. Root canal treatment was performed in one or two sessions. Pain intensity was assessed using the visual analogue scale before treatment and then 6h, 12h, 24h, 48h, 72h and one week after root canal treatment. The sample consisted of 46 women and 34 men. This study showed́ that postoperative pain was statistically associated with female gender (p=0.05), tooth types (p=0.006), and its location on the mandibular arch (p=0.03). The main finding was that patients with a higher intensity of pre-operative pain had a higher incidence of post-operative pain (p<0.05). In the group of patients who had no pre-operative pain, 63% (17/27) of patients remained asymptomatic after root canal treatment, while only 7.4% (2/27) had severe post-operative pain with a significant difference (p<0.05). However, in the group with severe pre-operative pain, 100% of patients had post-operative pain, of which 75% (15/20) of patients had high levels of pain requiring analgesics.

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Introduction: Skeletal unit growth may be due to epigenetic influence exerted by the functional matrix on the skeleton. Penn analysis is a method used to evaluate tomographically the transverse alterations of the maxilla. Objective: To analyze the association between transverse collapse of the maxilla and facial biotype in patients of the Polyclinic of the Orthodontics Postgraduate Program of the Autonomous University of Baja California, Mexicali campus. Materials and methods: An observational, analytical and cross-sectional study was carried out. The sample consisted of 75 patients who met the inclusion criteria. Initial tomographic studies were used to determine the presence of transverse collapse by means of Penn analysis. Lateral skull teleradiographs were plotted to determine the facial biotype by means of the Vert coefficient of Ricketts' lateral cephalometric analysis. The chi-square test was performed for statistical analysis of the association between the presence of transverse collapse of the maxilla and facial biotypes. Results: No significant results were found between the chi-square values and the p-value for patients with transverse collapse of the maxilla in association with facial biotypes. However, a statistical chi-square value of 4.8422 and a p-value of 0.2777 were obtained for the sample of female patients with transverse collapse of the maxilla. Conclusions: No association was found between the presence of maxillary transverse deficiencies and facial biotypes.

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The word "laser" is an acronym for Light Amplification by Stimulated Emission of Radiation. These words define the unique qualities of lasers, whose application in the dental field focuses on dental therapy, aesthetic dentistry, prosthetics, and oral and periodontal surgery. Through this literature review, the application of lasers in dental clinical practice and its relevant parameters will be evaluated from a bioengineering perspective. Bioengineering can serve as a transdisciplinary bridge between engineering and dentistry, which is refined in the use of lasers to enhance the oral health of patients.

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Introduction: Odontogenic maxillofacial cellulitis are infections of the cellulo -adipose tissues of the face of dental origin and which can be life-threatening for the patient. This study aims to determine the epidemiological and clinical profile of odontogenic maxillofacial cellulitis in children. Patients and Method: This is a retrospective, cross-sectional, observational, single-center study involving patients aged 0 to 18 years hospitalized at the CMF Stomatology department in Owendo from 2016 to 2022. Incomplete files, patients treated on an outpatient basis and those with non- odontogenic cellulitis. The epidemiological and clinical parameters studied were age, sex, residence, level of education, lifestyle, contributing factors, reason for consultation, consultation time, type of cellulitis, topography of the causal tooth, and sign of gravity. Results: 72 patients collected. The mean age was 9.03±5.71 years. The male gender represented 58% with a sex ratio of 1.4. 9.7% of patients brushed their teeth twice a day, 47.2% of patients did so once and 44.1% of patients did not brush their teeth. 54.2% of patients performed soft brushing, 2.8% of patients performed hard brushing. 79.2% of patients consumed cariogenic foods. 62.3% of patients self-medicated with NSAIDs. 56% of patients consulted between 1-10 days. 94% of patients presented with circumscribed cellulitis and 6% of patients presented with diffuse cellulitis. 5.6% of patients had dysphagia and 5.6% of patients had tight trismus. Conclusion: Maxioll-facial cellulite odontogenic infections are predominant in boys. They are favored by taking NSAIDs and cariogenic foods. The circumscribed stage is frequently encountered.

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Digital workflow in dentistry is an innovation technique that has made great progress in recent years that provides personalized patient care incorporating CAD/CAM technology (Computed Assisted Design/Computed Assisted Manufacturing) for the visualization and digital manipulation of structures obtained from CBCT (Cone Beam Computed Tomography) or intraoral scanner. This allows to build structures that can help the dentist in treating patients in a personalized way. The digital flow process mainly consists of three pillars: image acquisition, visualization and manipulation of three-dimensional models and 3D printing. This clinical methodology can be used in all fields of dentistry, where the design of anatomical posts to replace the use of conventional fiberglass poles stands out. The above allows to a predictable dynamic of treatment which influences the decrease of risk of fracture due to overload of chewing forces. The digital flow is improved with the integration of bioengineering, the technological and biological knowledge of this discipline allows increasing the effectiveness and efficiency of the process to obtain better results.

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Introduction: Maxillomandibular tumors are neoformations that develop on the mandible or maxilla, and may be benign or malignant. When they are related to elements of the dental system, they are called odontogenic maxillo-mandibular tumors. Objective: To study the anatomical and clinical features of odontogenic maxillo-mandibular tumors. Patients and Methods: This was a retrospective, observational, descriptive, analytical and monocentric study conducted in the Department of Stomatology and Maxillofacial Surgery over a 6-year period, from March 2016 to June 2022. All patients with histologically proven odontogenic maxillo-mandibular tumours were included. Non-odontogenic tumours and incomplete files were excluded. The parameters studied were: Epidemiological data (prevalence, sex, age, occupation, history), histo-clinical data (time to consultation, functional signs, physical signs), paraclinical data (imaging, anatomopathology). Results: The number of cases collected was 35. Odontogenic maxillo-mandibular tumours accounted for 34.3% of all maxillo-mandibular tumours. The mean age was 31.63 years, with extremes ranging from 03 to 68 years. The sex ratio was 0.94, with females predominating. Unemployment accounted for 40% of cases. Maxillary or mandibular swelling was present in 94.3% of patients, and dental extraction was performed in 34.3%. CT scans were performed in 82.8% of patients. Anatomopathological examination revealed 88.6% benign tumours and 11.4% malignant tumours (4 patients). Ameloblastoma accounted for 61.3% of benign tumours. Ameloblastic carcinoma accounted for 50% of malignant tumours. Conclusion: Maxillo-mandibular odontogenic tumours are common and are revealed by maxillary or mandibular swelling. Their characteristics differ according to whether they are benign or malignant. Ameloblastoma is the most common maxillo-mandibular odontogenic tumor.

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The arrival of digital workflow has caused an important evolution in the way dentistry is performed nowadays. Imaging through intraoral scanning systems (IOS) and cone beam computed tomography (CBCT) combined with computer aided design and manufacturing systems (CAD/CAM), make it possible to simplify procedures in all areas of dentistry. Digital techniques are tools that allow more assertive diagnoses, as well as the planning and development of treatments with greater safety, effectiveness and speed. The purpose of this review is to learn about the application of the digital tools that give rise to the development of digital workflow and its general applications in dentistry, in the search for areas of opportunity where this technology can be useful for the development of new techniques that allow that allow for personalized patient-centered care.

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The aim of the study was to compare and evaluate fracture resistance of Custom Cast post and core, Pre-fabricated post and core and CAD/CAM fabricated post and core. Material and Methods: 60 transparent endoblocks with single root canal that simulated natural teeth were randomly divided into 3 groups of 20 endoblocks each. The working length of the root canal in the transparent endobloc was determined. The canals were prepared with K-file sizes 10,15 and 20 followed by Protaper Ni-Ti files (sizes S1, S2, F1 and F2); Dentsply by using the crown down technique to the full working length. Gutta percha was removed from the root canals with Peeso drills to a depth of 12 and post spaces were prepared in all groups with the special preparation drills of each system leaving 5mm of gutta percha in all specimens. For group 1, after root canal treatment of 20 samples, Prefabricated plastic burnout posts were coated with pattern resin and then inserted into the canal with slight pressure to take the canal impression which was further send for casting followed by using GC gold label glass ionomer resin for luting. For group 2, the Prefabricated EDELWEISS post and core were placed into the canal and the cement was allowed to set. For group 3 impression of the canal was made using pattern resin. The burnout post was scanned with a lab scanner and designing was done using the designing software. CAD-CAM fabricated post and core was placed into the canal and luted with the help of glass ionomer cement. Composite core fabrication was done and the specimens were secured in a universal load-testing machine at an angle of 1300 to the long axis of the tooth. Until fracture occurred, a compressive force was applied at a crosshead speed of 1 mm/min. The fracture loads were determined. Mean failure load for each group was recorded in N. Results: The mean fracture load of Group 1, was found to the maximum followed by Group 3 & Group 2 samples, in decreasing order. Conclusion: The mean ......