Is the assessment of the mandibular molar danger zone affected by field of view and voxel size in cone beam computed tomography examinations?

OBJECTIVE: To verify if assessment of the danger zone (DZ) in the mesial root of mandibular molars is affected by field of view (FOV) and voxel sizes in cone beam computed tomography (CBCT) scans. STUDY DESIGN: Forty mandibular molars were scanned by micro-computed tomography, creating the reference standard. The teeth were then submitted for CBCT scans with FOVs of 10 × 5.5 cm and 5 × 5.5 cm and voxel sizes of 0.4, 0.2, 0.15, and 0.075 mm3. The smallest dentin thickness in the DZ from the mesiobuccal and mesiolingual canals was measured at 2, 4, and 6 mm apical to the root furcation. Descriptive statistics, paired t-tests, and intraclass correlation coefficients were used for statistical analysis with significance established at P < .05. RESULTS: All CBCT measurements overestimated the DZ dentin thickness (P < .001) compared to the reference standard. The greatest overestimation occurred in the 5 × 5.5 cm FOV with 0.4 mm3 voxels (P = .007). Dentin thickness measured with the 5 × 5.5 cm FOV and 0.075 mm3 voxels was significantly smaller and produced the best ICC value with the reference standard (0.936). CONCLUSIONS: CBCT overestimates the dentin thickness of the DZ regardless of FOV and voxel sizes. The 5 × 5.5 cm FOV showed the best performance with the 0.075 mm3 voxel size, but it performed poorly with 0.4 mm3 voxels.

Assessing the Impact of the Metal Artifact Reduction Tool on Detecting Furcation Lesions in Maxillary Molars with Different Intracanal Posts: An Ex Vivo Cone-beam Computed Tomography Study.

INTRODUCTION: Considering the potential image compromise and diagnostic challenges posed by metals, this study aimed to assess the efficacy of the metal artifact reduction (MAR) tool in cone-beam computed tomography examinations for detecting furcation lesions in upper molars treated endodontically and restored with different intracanal posts. METHODS: This ex vivo study used 45 endodontically treated maxillary first molars, categorized into the following3 groups (n = 15): control (without intracanal post), metal post, and fiberglass post. Simulations were conducted in the laboratory to replicate alveolar bone, periodontal ligament, and grade I, II, and III furcation lesions. Cone-beam computed tomography scans were obtained with and without the MAR tool, and the furcation lesions were evaluated considering a 5-point Likert scale. Data were analyzed at 5%. RESULTS: In the control group, there was no influence of MAR (P > .05); grade II lesions were not diagnosed, and grade III lesions were the most detected (P < .05). In the metal post group with MAR, grade III lesions were diagnosed more frequently than I and II (P < .05) and grade III without MAR (P < .05). In the fiberglass post group, the diagnosis of grade I lesions decreased with MAR (P < .05), and without MAR, grade III was most diagnosed (P < .05); grade III lesions were the most diagnosed (P < .05). CONCLUSIONS: The MAR tool was only effective for diagnosing grade III furcation lesions, regardless of the intracanal material. Its application for grade I and II lesions did not contribute to improved diagnosis. Furthermore, in the fiberglass post group with grade I lesions, the MAR tool negatively affected the detection of the lesions.

Dental caries in HIV-infected children and adolescents: A systematic review with meta-analysis.

This study aimed to evaluate and compare the risk of dental caries in between human immunodeficiency virus (HIV)-infected and uninfected children and adolescents. An electronic search was performed on PubMed/MEDLINE, Web-of-Science, Scopus, LILACS, ProQuest, and ClinicalTrials.gov up to May 2022. The critical appraisal checklist developed by the Joanna Briggs Institute was used to evaluate the quality of the included studies. Meta-analysis was performed using the RevMan 5.4. Sixteen studies were included. A total of 3231 participants were evaluated, including 1701 and 1530 HIV-infected and uninfected children and adolescents, respectively. The meta-analysis revealed a higher risk of dental caries for primary dentitions in HIV-infected children and adolescents by decayed, missing, filled tooth (dmft) (SMD:0.34; p = 0.006) and decayed, missing, filled surface (dmfs) scores (SMD:0.37; p = 0.001). Similar results were observed for permanent dentition, with increased dental caries in HIV-infected children and adolescents with DMFT (SMD:0.32; p = 0.003) and DMFS (SMD:1.78; p < 0.0001) scores. Regarding the quality assessment, most of the included studies were moderate or good quality. However, the certainty of the evidence of the outcomes was very low. This systematic review and meta-analysis showed higher caries severity in permanent and deciduous teeth among HIV-infected children and adolescents.

Associated oral manifestations with HIV southeastern Brazilian patients on antiretroviral therapy

Abstract Objectives This study aimed to assess the prevalence of oral lesions in patients living with HIV infection and their association with CD4 count, viral load, and antiretroviral therapy in patients with HIV. Methods A cross-sectional study was conducted on a sample of 161 patients attending the… All the patients were examined for their oral lesions, current CD4 counts, type, and duration of the therapy. Data analyses were carried out using Chi-Square, Student T/Mann-Whitney, and logistic regression tests. Results Oral lesions were observed in 58.39% of patients with HIV. Periodontal disease with 78 (48.45%) or without mobility 79 (49.07%) was observed more frequently, followed by hyperpigmentation of oral mucosa 23 (14.29%), Linear Gingival Erythema (LGE) 15 (9.32%), candidiasis pseudomembranous 14 (8.70%). Oral Hairy Leukoplakia (OHL) was observed only in 3 (1.86%). A relationship between periodontal disease with dental mobility and smoking was found (p = 0.04), as well duration of treatment (p = 1.53e-3) and age (p = 0.02). Hyperpigmentation was related to race (p = 0.01) and smoking (p = 1.30e-6). CD4 count, CD4:CD8 ratio, viral load, or type of treatment were not associated with oral lesions. Logistic regression showed that the duration of treatment has a protective effect on the periodontal disease with dental mobility (OR = 0.28 [−2.27 to −0.25]; p-value = 0.03), independent of age or smoking. To hyperpigmentation, the best model included smoking (OR = 8.47 [1.18-3.10], p = 1.31e-5), without race or type and duration of treatment. Conclusion Among HIV patients undergoing antiretroviral treatment, oral lesions can be observed, predominantly periodontal disease. Pseudomembranous candidiasis and oral hairy leukoplakia were also observed. No relationship was found between associated oral manifestations in HIV patients and the start of the treatment, TCD4+ and TCD8+ cell count, TCD4:TCD8 ratio, or viral load. The data indicate that there is a protective effect of duration of treatment with relation to periodontal disease with mobility and that hyperpigmentation seems to be more related to smoking than type and duration of treatment. Level of evidence Level 3 (OCEBM Levels of Evidence Working Group*. "The Oxford 2011 Levels of Evidence").

Associated oral manifestations with HIV southeastern Brazilian patients on antiretroviral therapy.

OBJECTIVES: This study aimed to assess the prevalence of oral lesions in patients living with HIV infection and their association with CD4 count, viral load, and antiretroviral therapy in patients with HIV. METHODS: A cross-sectional study was conducted on a sample of 161 patients attending the… All the patients were examined for their oral lesions, current CD4 counts, type, and duration of the therapy. Data analyses were carried out using Chi-Square, Student T/Mann-Whitney, and logistic regression tests. RESULTS: Oral lesions were observed in 58.39% of patients with HIV. Periodontal disease with 78 (48.45%) or without mobility 79 (49.07%) was observed more frequently, followed by hyperpigmentation of oral mucosa 23 (14.29%), Linear Gingival Erythema (LGE) 15 (9.32%), candidiasis pseudomembranous 14 (8.70%). Oral Hairy Leukoplakia (OHL) was observed only in 3 (1.86%). A relationship between periodontal disease with dental mobility and smoking was found (p=0.04), as well duration of treatment (p=1.53e-3) and age (p=0.02). Hyperpigmentation was related to race (p=0.01) and smoking (p=1.30e-6). CD4 count, CD4:CD8 ratio, viral load, or type of treatment were not associated with oral lesions. Logistic regression showed that the duration of treatment has a protective effect on the periodontal disease with dental mobility (OR = 0.28 [-2.27 to -0.25]; p-value=0.03), independent of age or smoking. To hyperpigmentation, the best model included smoking (OR=8.47 [1.18-3.10], p= 1.31e-5), without race or type and duration of treatment. CONCLUSION: Among HIV patients undergoing antiretroviral treatment, oral lesions can be observed, predominantly periodontal disease. Pseudomembranous candidiasis and oral hairy leukoplakia were also observed. No relationship was found between associated oral manifestations in HIV patients and the start of the treatment, TCD4+ and TCD8+ cell count, TCD4:TCD8 ratio, or viral load. The data indicate that there is a protective effect of duration of treatment with relation to periodontal disease with mobility and that hyperpigmentation seems to be more related to smoking than type and duration of treatment. LEVEL OF EVIDENCE: Level 3 (OCEBM Levels of Evidence Working Group*. "The Oxford 2011 Levels of Evidence").

Evaluation of Alveolar Bone Dimensions and Root Positioning of Anterior Teeth in the Maxilla.

Buccal bone walls present significant resorption after tooth extraction, possibly related to the smaller bone thickness, length, and the sagittal position of the root, as well as the bone morphology. The goal of the present study was to measure the thickness of the cortical bone of the vestibular and palatal walls in the anterior maxilla by means of CBCT images. Measurements were taken from CBCT scans of 300 maxillary anterior teeth from 50 patients (25 women, 25 men) aged 18 to 30 years. The parameters evaluated included the thickness of the buccal and palatal cortical bone in the cervical, apical, and middle thirds of the root, as well as six specific angular measurements from each tooth. The lateral incisors showed a significant difference in thickness between each of the buccal and palatal thirds, and measurements were also significantly smaller than the central and canine incisors. Bone anatomy is tooth-and location-specific, and thus the sagittal root position within the alveolus influences the regional bone morphology and may explain the gingival zenith position in the anterior maxilla. These specific buccal and palatal anatomic parameters should be carefully taken into consideration for surgical planning and intervention in the esthetic area.

Fracture resistance of weakened roots restored with relined or milled CAD-CAM glass fiber posts.

This in vitro study compared the fracture resistance of weakened roots restored with milled or relined glass fiber post (GFP). Seventy bovine incisors were divided into seven groups, according to the weakening protocol (none: control; medium-weakened: MW; highly-weakened: HW) and post anatomization technique (non-relined, relined with Bulk Fill or Z350 resin; milled GFP: M). Roots were thermomechanical cycled and submitted to compression. Frequencies and groups were compared by the chi-square test and two-factor ANOVA, Tukey's, and t-test (α=5%). The HW-M obtained the lowest values, showing significant differences compared to all groups (p<0.001). The highest value was HW-Bulk fill, with significant difference compared to MW-M (p=0.037) and HW-M (p<0.001). The frequency of repairable fractures was 100% in the control, 87%, and 63% in the MW and HW, respectively. Relined or milled GFPs can be considered to rehabilitate weakened teeth since failure patterns were predominantly repairable in all groups.

The effectiveness of EDTA 17% as a cleaning solution for the fiber post space after filling with cements

Aim: To evaluate the resistance of the union between a glass fiber post and radicular dentine after cleaning the root with 17% EDTA and filling with different endodontic cements. Methods: Forty uniradicular bovine incisors were removed to obtain root lengths of 18 mm. Endodontic treatment was performed on all roots using different filling cements (zinc oxide and eugenol-based, OZE; cement based on epoxy resin, AH) and cleaning solutions (saline, SA or EDTA), which made it possible to obtain four groups: OZESA, OZEEDTA, AHSA and AHEDTA. Subsequently, 12 mm of filling material was removed from the roots, and they were prepared to receive fiber posts luted with resin cement. To execute the mechanical cycles (2x106 cycles, 90 N, 4 Hz), coronal reconstruction was performed with a silicon matrix. The roots were then sliced (2-mm thick) to perform the push-out test. The results were analyzed using analysis of variance (one factor and two factors) and Tukey's test (α=0,05). Results: Bond strength (Mpa) was significantly higher for OZEEDTA (9,18) and AHEDTA (8,70) than for OZESA (6,06) AHSA (8,7). OZEEDTA also presented the highest values in the cervical region (15,18) but was significantly lower in the apical region (2,99). However, AHEDTA had a homogeneous bond strength in all thirds. Conclusion: Regardless of the endodontic cement used, EDTA was used as an irrigating solution, culminating in a higher bond strength between the glass fiber post and dentin

Relação entre a recorrência do herpes simples e o estresse durante a pandemia de covid-19 em estudantes de odontologia / Relation between the recurrence of herpes simplex and stress during the covid-19 pandemic in dental students

Introdução: A infecção viral causada pelo HSV-1 leva ao aparecimento das lesões do herpes simples e é caracterizada por períodos de infecção primária, latência e recorrência. Durante a vida do indivíduo esta infecção pode ser reativada por diversos fatores como o estresse. No contexto pandêmico de COVID-19, observa-se um aumento de efeitos psicológicos negativos derivados da exaustão emocional entre os estudantes universitários. Objetivo: Avaliar a relação entre o estresse e a recorrência de lesões do herpes simples bucal durante a pandemia de COVID-19 nos estudantes de graduação em odontologia. Materiais e Métodos: Este estudo observacional, descritivo, transversal e de abordagem quali-quantitativo, foi realizado com uma população constituída por 347 estudantes de odontologia, maiores de 18 anos independente de gênero e cor da pele, que já apresentaram episódios primários e/ou recorrentes de herpes simples bucal antes da pandemia de COVID-19. Foram excluídos os estudantes matriculados em odontologia que se recusaram a concordar com o termo de consentimento livre e esclarecido (TCLE). Resultados: A maioria dos participantes era do gênero feminino (81%) com idade entre 20 e 23 anos. Somente 8% apresentaram recorrência das lesões do herpes simples durante o período pandêmico. Entre eles, 78% apresentaram 1 vez, 11% indicaram 4 vezes e 11% revelaram 5 vezes. Analisou-se o nível de estresse, ansiedade e depressão dos participantes por meio da escala DASS-21 e observou-se que entre os colaboradores que apresentaram recorrência do herpes simples bucal, 44% apresentavam ansiedade grave. Ademais, 44% dos participantes manifestaram nível grave e outros 44% nível moderado de estresse. Conclusão: O estudo mostrou o impacto negativo que o período da pandemia de COVID-19 tem causado nos estudantes de odontologia. Notou-se que a parcela da população que apresentou a recorrência das manifestações do vírus em grande maioria indicou ansiedade no nível grave e estresse nos níveis moderado e grave.

Introduction: The viral infection caused by HSV-1 leads to manifestation of herpes simplex lesions and is characterized by periods of primary infection, latency and recurrence. During the individual's life, this infection can be reactivated by several factors such as stress. In the COVID-19 pandemic context, an increase in negative psychological effects derived from emotional exhaustion among university students is observed. Objective: To evaluate the relationship between stress and recurrence of oral herpes simplex lesions during the COVID-19 pandemic in undergraduate dentistry students. Materials and Methods: This observational, descriptive, cross-sectional study, with a quali-quantitative approach, was carried out with a population consisting of 347 dentistry students, over 18 years old, regardless of gender and skin color, who had already had primary episodes and/or recurrent oral herpes simplex before the COVID-19 pandemic. Students enrolled in Dentistry who refused to agree to the free and informed consent form (ICF) were excluded. Results: Most participants were female (81%), aged between 20 and 23 years. Only 8% had recurrence of herpes simplex lesions during the pandemic period. Among them, 78% presented 1 time, 11% indicated 4 times and 11% revealed 5 times. The level of stress, anxiety and depression of the participants was analyzed using the DASS-21 scale and it was observed that among the collaborators who presented recurrence of oral herpes simplex, 44% had severe anxiety. Besides, 44% of participants expressed a severe level and another 44% moderate level of stress. Conclusion: The study showed the negative impact that the period of the COVID-19 pandemic has caused in dentistry students. It was noted that the portion of thepopulation that presented the recurrence of the manifestations of the virus in the vast majority indicated severe level anxiety and stress at moderate and severe levels

Factors associated with advanced-stage oral and oropharyngeal squamous cell carcinoma in a Brazilian population

Diagnosis of oral and oropharyngeal cancer in advanced stages may be associated with social nature factors, access to health care, education, occupation, and behavioral/ cultural factors. Aim: To determine the factors related to high clinical-staging in patients diagnosed with squamous cell carcinoma in the oral and oropharyngeal region in a Cancer Center in Brazil between 2009 and 2015. Methods: It is an epidemiological, retrospective, and exploratory study. Patients diagnosed with squamous cell carcinoma had their medical records analyzed. The variables considered were sociodemographic, lifestyle, and disease characteristics. Descriptive and exploratory tests (Pearson's, chi-square test and, Student's t-test) were realized. Results: We analyzed 365 patient records, among which 289 (79.17%) were male, and 73 (20.0%) were female. Age ranged from 16 to 101 years, with a mean of 61.13. Regarding education, 157 (43.01%) studied < 8 years, 103 (28.21%) were illiterate and 102 (27.94%) studied > 8 years. 305 (83.56%) patients live in urban areas. There was an association between high clinical-staging and low educational level. For high clinical-staging, symptomatology, tobacco, and alcohol intake as well. Conclusion: Patients with low educational levels tend to report the disease later, and their diagnostics occurred in advanced stages. Thus, specific public health policies for this population, including access to dental care to recognize the clinical signs and early diagnosis, are necessary

Assessment of the Metal Artifact Reduction Tool for the Detection of Root Isthmus in Mandibular Molars with Intraradicular Posts in Cone-beam Computed Tomographic Scans.

INTRODUCTION: This study evaluated the performance of the metal artifact reduction (MAR) tool in cone-beam computed tomographic scans using different fields of view (FOVs) in the detection of a root isthmus in mandibular molars with intraradicular posts. METHODS: Twenty-eight teeth were scanned by micro-computed tomographic imaging (gold standard images). Thereafter, specimens were allocated into the following groups: gutta-percha (teeth without posts, n = 10), a prefabricated metal post (n = 9), and a fiberglass post (n = 9). Cone-beam computed tomographic scans were taken using 8 acquisition protocols, varying the size of the FOV (10 × 5.5 cm and 5 × 5.5 cm) and the MAR tool (disabled, low, normal, and high modes). A root isthmus was evaluated considering a 5-point scale. Data were analyzed considering a 5% significance level. RESULTS: Intra- and interexaminer agreement varied from moderate to substantial. The frequency of correct diagnosis varied significantly in all groups regardless of the image acquisition protocol selected (P < .05). In the gutta-percha group, there was no difference in the accuracy, sensitivity, and specificity values between the tested protocols. In the metal and fiberglass post groups, the accuracy values were higher with the "disabled" and "low" modes of the MAR tool regardless of the FOV size. This was also observed for the sensitivity values in the metal post group (P < .05). CONCLUSIONS: The size of the FOV did not affect the performance of the MAR tool in the diagnosis of a root isthmus in molars with intraradicular posts. Our findings suggest that the use of the tool in the "normal" and "high" modes is contraindicated for this purpose.

Probability of oral complications of radiotherapy and chemotherapy for head and neck cancer.

The objective of this study was to investigate the relationship between antineoplastic treatments and oral complications in patients with head and neck cancer. Medical records from 400 patients treated at a cancer center were analyzed. Univariable analysis was initially performed to verify the association between the variables and the presence of oral complications. Multivariable analysis was performed using multiple linear regression to assess the association between the type of treatment performed and the presence and types of oral complications. The medical records of 290 patients included information about the presence or absence of oral complications of therapy, and 199 of these patients experienced oral complications. An average of 1 oral complication per patient was found; 104 patients experienced 1 complication, 74 patients experienced 2 complications, and 21 patients experienced 3 or 4 complications. Oral complications were correlated with tobacco use (P = 0.01), alcohol use (P = 0.006), radiotherapy (P = 0.000), and chemotherapy (P = 0.028). The association between oral complications and radiotherapy was greater than the association between oral complications and chemotherapy, but the risk increased when both therapies were performed (odds ratio [OR] = 4.41; P = 0.004). Mucositis was associated with both radiotherapy and chemotherapy, and the incidence increased when both types of treatment were combined (OR = 5.28; P = 0.001). Oral complications of antineoplastic therapy are related to lifestyle habits and treatment modalities. Clinicians should educate patients with head and neck cancer about the role of lifestyle habits in possible adverse treatment effects and consider a more careful approach to follow-up care of patients who are undergoing both radiotherapy and chemotherapy.

Reliability of panoramic radiography in predicting proximity of third molars to the mandibular canal: A comparison using cone-beam computed tomography.

PURPOSE: The purpose of this study was to analyze the reliability of 7 panoramic radiographic signs for predicting proximity of the root apices of mandibular third molars to the mandibular canal using cone-beam computed tomography and to correlate these findings with the Pell and Gregory and the Winter classification systems. MATERIALS AND METHODS: An observational, cross-sectional, descriptive study was conducted on 74 patients with bilateral impacted mandibular third molars. Four panoramic radiographic signs were observed in the tooth root (darkening, deflection, and narrowing of the root apices, and bifid apices), and another 3 in the mandibular canal (diversion, narrowing, and interruption of the mandibular canal). Cone-beam computed tomography images were analyzed to identify disruption and diversion of the mandibular canal and root deflection. RESULTS: Binary logistic regression showed that only 4 of the 7 panoramic radiographic signs were able to predict proximity of the root apices of the mandibular third molars to the mandibular canal: darkening of the root, deflection of the root, narrowing of the root, and interruption of the mandibular canal (P<0.05). CONCLUSION: Darkening, deflection, and narrowing of the root, in tandem with the interruption of the mandibular canal on panoramic radiographs, indicate that cone-beam computed tomography should be performed when planning the extraction of impacted mandibular third molars. Proximity between mandibular third molars and the mandibular canal is correlated with the Winter classification.

Morphometric analysis of the mandibular fossa in dentate and edentulous patients: A cone beam computed tomography study.

STATEMENT OF PROBLEM: Mandibular fossa roof thickness and lateral inclination could be associated with the presence of bone changes in the mandibular condyle in dentate and edentulous patients. However, literature regarding the relationship between the presence and absence of teeth and the morphologic features of the temporomandibular joint is lacking. This knowledge could provide a better understanding of changes affecting the correct functioning of the stomatognathic system. PURPOSE: The purpose of this clinical study was to assess the mandibular fossa roof thickness and lateral inclination in relation to sex, presence or absence of teeth, and bone changes in the mandibular condyle through cone beam computed tomography (CBCT). MATERIAL AND METHODS: CBCT scans of 100 individuals (50 dentate and 50 edentulous) were evaluated in terms of mandibular fossa roof thickness and lateral inclination. Bone changes in the mandibular condyle were classified dichotomously in relation to osteophytes, erosion, sclerosis, and flattening. Differences were assessed with the Student t test, the chi-square test, and 2-way analysis of variance (ANOVA), with Tukey post hoc tests (α=.05). RESULTS: Sex was not related to mandibular fossa measurements. Edentulous participants showed a higher mandibular fossa lateral inclination (P<.001) and lower roof thickness (P=.001) than dentate participants. When the association between bone changes in the mandibular condyle was evaluated in dentate and edentulous groups, only sclerosis showed a statistically significant association (P<.001). The 2-way ANOVA showed that the mandibular fossa roof thickness was lower in edentulous participants in the presence of flattening and erosion and that the mandibular fossa lateral inclination was higher in the presence of osteophytes, erosion, and sclerosis (P<.001). Among dentate participants, the mandibular fossa lateral inclination was higher in the presence of flattening (P=.024). CONCLUSIONS: Mandibular fossa roof thickness and lateral inclination are not associated with sex. However, tooth absence and bone changes in the mandibular condyle are related to mandibular fossa measurements.

Missed canals in endodontically treated maxillary molars of a Brazilian subpopulation: prevalence and association with periapical lesion using cone-beam computed tomography.

OBJECTIVES: To evaluate the prevalence of missed canals in endodontically treated maxillary molars through cone-beam computed tomography (CBCT) images and to verify their association with the presence of periapical lesions. MATERIAL AND METHODS: Three oral radiologists evaluated 633 maxillary molars in CBCT exams regarding number of roots, number of root canals, number of missed canals, anatomic identification of missed canals, presence of periapical lesions, and root location of the periapical lesions. Data were statistically analyzed at a 5% significance level. RESULTS: Descriptive statistical analysis showed that among 395 first molars, 218 had at least one missed canal, and 186 (46.5%) had a missed canal and periapical lesion simultaneously. Of these, 72.4% (134) of the missed canals were only mesiobuccal 2 (MB2). Among 238 s molars evaluated, 121 presented at least one missed canal, and 104 (43.6%) had a missed canal and periapical lesion simultaneously. Of these, 81.7% (85) of the missed canals were only MB2. The chi-squared test showed an association between the presence of missed canals and periapical lesions for 1st and 2nd maxillary molars. Teeth that presented a missed canal showed an odds ratio (OR) of 2.57 (p < 0.0001) of being associated with a periapical lesion. Missed canal occurrence was positively related to the number of root canals (z = 13.06, p < 0.0001), meaning when the number of root canals is higher, there is a higher probability of missed canal occurrence. According to the model calculated prediction, for a one-unit increase in the number of canals, the probability of missed canals increases by 4.22%. CONCLUSIONS: It was concluded that MB2 was the most frequently missed canal, associated with the presence of periapical lesions in endodontically treated maxillary molars. CLINICAL RELEVANCE: Professionals' negligence of anatomical root variations has been contributed to the high prevalence of missed canals, leading to failures in endodontic treatment. Their association with periapical lesion occurrence emphasizes the importance of correct detection and instrumentation of these canals.

Evaluation of different teaching methods in the radiographic diagnosis of proximal carious lesions.

OBJECTIVES: To evaluate four different teaching methodologies in the radiographic diagnosis of proximal carious lesions and in the students' perception of these methodologies. METHODS: 71 undergraduate dental students were subdivided into 4 groups according to the teaching methodologies used (traditional, hybrid, e-learning and problem-based learning). All methods were applied by two properly trained researchers. Initially, students completed a pre-methodology test (index test). After applying the teaching methodologies, the students were submitted to a post-methodology test containing periapical radiographs for evaluation of proximal carious lesions. Then, the students answered a questionnaire to verify their perception of the different teaching methodologies. Statistical analysis was done. RESULTS: There were no relationship between the results of pre- and post-methodologies tests, irrespective of the teaching methodology employed (p > 0.05). No differences between the teaching methodologies studied (p > 0.05) were found regarding the amount of correct answers. However, the students who participated in the active (e-learning and problem-based learning) and hybrid teaching methodology reported a positive impact in relation to their diagnostic skills at the questionnaire. CONCLUSIONS: All the tested methodologies had a similar performance; however, the traditional methodology showed less acceptance by the students when analyzed subjectively and comparatively. The results of the present study increase comprehension about teaching methodologies for radiographic diagnosis of proximal carious lesions, and there is a potential to build on the knowledge base and provide practical support for students and educators.

Intra-articular calcifications of the temporomandibular joint and associations with degenerative bone alterations.

PURPOSE: The purpose of this study was to use cone-beam computed tomography (CBCT) images to determine the prevalence of calcifications in the temporomandibular joint (TMJ) and to evaluate any associations between the presence of such calcifications and degenerative bone alterations of the TMJ, sex, or age. MATERIALS AND METHODS: In this retrospective study, 1,058 CBCT exams were analyzed, and data regarding the presence and quantity of calcifications, the affected side, any degenerative alterations of the condyle, sex, and age were collected. To evaluate associations between the presence of calcifications and sex or age, the Fisher exact test or the Spearman correlation coefficient, respectively, was used. To assess the association between the presence of calcifications and joint bone alterations, the chi-square and Fisher exact tests were used. The significance level adopted was 5% (P<0.05). RESULTS: Twenty-eight patients (2.7%) presented with TMJ calcifications, including 23 women (82.1%) and 5 men (17.9%). Significant correlations were found between the presence of calcifications and age (P<0.05) and between the presence of calcifications and the presence of condylar alterations (P<0.05), with 73.2% of patients with bone alterations having TMJ calcifications. CONCLUSION: It may be concluded that, although rare (with a prevalence of only 2.7%), intra-articular calcifications are associated with both degenerative bone alterations and age.

Anatomical evaluation of the relationship between the maxillary posterior teeth and maxillary sinus.

Knowledge of the anatomical relationships between the maxillary sinus (MS) and posterior teeth is important to prevent complications when endodontic or oral surgical procedures are performed. The aim of this study was to evaluate the relationships between the root apices of maxillary posterior teeth and the MS floor. Three oral radiologists evaluated 851 posterior teeth (1969 roots) imaged with cone beam computed tomography. The roots were analyzed individually in parasagittal sections, on which the most superior point of the apex was observed. A qualitative evaluation was performed, and each root was assigned a proximity score: 1, root invaginating the MS; 2, root in close contact with the MS floor; 3, root with no relationship with the MS; and 4, root with a measurable proximity to the MS. For roots classified as score 4, the distance to the MS floor was measured (quantitative analysis). Student t tests, 1-way analysis of variance, and simple linear regression analysis were performed (P < 0.05). The qualitative analysis revealed that the mesiobuccal root of the second molar had a pronounced proximity to the MS. The quantitative analysis revealed no differences in distance to the MS between right and left posterior teeth or between the different roots of the same tooth. In relation to the MS, the second molar was positioned closest, followed by the first molar, second premolar, and first premolar. Except for the comparison between mean distances of the second premolar and first molar (P = 0.11), the differences between groups of teeth were statistically significant (P < 0.05). Simple linear regression analysis showed that the more posterior the tooth was in relation to the midline, the shorter the mean distance from the root apex to the MS floor (P < 0.05). The mesiobuccal roots of second molars were closest to the MS. Second molars exhibited the shortest distances between their root apices and the MS and the greatest number of roots that were invaginating or in close contact with the MS. Therefore, second molars require special attention when endodontic or oral surgical approaches involve those regions.

Dental students' ability to detect maxillary sinus abnormalities: A comparison between panoramic radiography and cone-beam computed tomography.

PURPOSE: To compare the diagnostic ability of undergraduate dental students to detect maxillary sinus abnormalities in panoramic radiographs (PR) and cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This was a retrospective study based on the evaluation of PR and CBCT images. A pilot study was conducted to determine the number of students eligible to participate in the study. The images were evaluated by 2 students, and 280 maxillary sinuses were assessed using the following categories: normal, mucosal thickening, sinus polyp, antral pseudocyst, nonspecific opacification, periostitis, antrolith, and antrolith associated with mucosal thickening. The reference standard was established by the consensus of 2 oral radiologists based on the CBCT images. The kappa test, receiver operating characteristic curves, and 1-way analysis of variance with the Tukey-Kramer post-hoc test were employed. RESULTS: Intraobserver and interobserver reliability showed agreement ranging from substantial (0.809) to almost perfect (0.922). The agreement between the students' evaluations and the reference standard was reasonable (0.258) for PR and substantial (0.692) for CBCT. Comparisons of values of sensitivity, specificity, and accuracy showed that CBCT was significantly better (P<0.05). CONCLUSION: CBCT was better than PR for the detection of maxillary sinus abnormalities by dental students. However, CBCT should only be requested after a careful analysis of PR by students and more experienced professionals.

Periapical and Endodontic Status Scale for Endodontically Treated Teeth and Their Association with Maxillary Sinus Abnormalities: A Cone-beam Computed Tomographic Study.

INTRODUCTION: This retrospective cross-sectional study investigated the applicability of the periapical and endodontic status scale (PESS) to determine the association of endodontically treated teeth with maxillary sinus (MS) abnormalities through cone-beam computed tomographic imaging. METHODS: A total of 631 endodontically treated teeth were analyzed. MS abnormalities were classified as mucosal thickening, sinus polyp, antral pseudocyst, nonspecific opacification, periostitis, and antral calcification. The PESS was used to evaluate the quality of endodontic treatment as well as periapical tissue conditions. The data were analyzed by chi-square tests (P < .05). RESULTS: MS abnormalities were detected in 70.52% of the sample, with a greater prevalence of mucosal thickening (38.19%), whereas periapical lesions were observed in 55.94% of the cases. Treated root canals with unsatisfactory filling, homogeneity, and coronal sealing had an odds Ratio (OR) of 2.21, 2.88, and 2.99, respectively (P < .001). Periapical lesions larger than 5 mm (OR = 314.95), in more than 1 root (OR = 3.72), involving the furcation region (OR = 5.21), in contact with important structures (OR = 7.37), and with cortical bone destruction (OR = 4.09) were significantly related to the presence of MS abnormalities (P < .001). An OR of 99,668 was observed in periostitis lesions greater than 5 mm (P < .001). CONCLUSIONS: The PESS proved to be an important tool for the analysis of endodontic and periapical conditions and was applicable to determine potential associations with MS abnormalities.