Guided Endodontic Access in a Calcified Central Incisor: A Conservative Alternative for Endodontic Therapy

Guided endodontic access is a promising method to treat teeth with pulp calcification. This report aimed to describe a case of root canal treatment performed through guided endodontic access in a calcified anterior tooth with apical periodontitis. A 23-year-old female with a history of trauma 10 years ago in the anterior maxilla was referred to the dental office.  Her chief complaint was discolouration of the left central incisor crown. The tooth was sensitive to percussion and responded negatively to pulp sensitivity tests. The periapical radiography showed pulp calcification and periapical radiolucency. Cone-beam computed tomography (CBCT) was obtained to allow a more detailed view of the pulp canal and the periapical area. An intraoral scan was performed and the standard tessellation language (STL) archive was combined with digital imaging and communications on medicine (DICOM) images from CBCT in the Implant Viewer software. Subsequently, a 3D model was designed and printed to guide the endodontic access in position and appropriate angulation for dental instrumentation. The mold was positioned on the patient's tooth and the root canal treatment was performed. After two years, complete healing of periapical tissues was observed. This method facilitates the drill targeting during access, reducing the risk of deviations and perforations

Major salivary glands magnetic resonance imaging

Objetivos: Fornecer informações básicas sobre as modalidades de ressonância magnética (RM), enfatizando o método da imagem ponderada em difusão, bem como apontar sua aplicabilidade para diagnosticar doenças das glândulas salivares maiores. Métodos: O método Prisma foi usado durante a extração e avaliação dos dados. As buscas foram feitas no banco de dados MEDLINE (PubMed) considerando o período de 2010 a novembro de 2017 e estudos que contivessem informações básicas sobre as modalidades de RM, bem como seu uso para diagnosticar doenças das glândulas salivares. A extração de dados incluiu informações sobre a aplicação das modalidades de RM, especialmente dos métodos de coeficiente de difusão aparente e da imagem ponderada em difusão, para diagnosticar doenças das glândulas salivares maiores. Resultados: A busca encontrou 58 publicações no MEDLINE (PubMed). A triagem inicial das publicações foi realizada usando os resumos e palavras-chave. Após a aplicação dos critérios de exclusão, um total de 9 estudos foi identificado como elegível para ser avaliado. Os estudos apontaram dois tipos principais de modalidades de RM: o coeficiente de difusão aparente e a imagem ponderada em difusão. A maioria dos estudos sugere que a RM pode ser uma útil ferramenta de diagnóstico para as glândulas salivares maiores. Conclusão: Modalidades de RM são vantajosas ferramentas para avaliações dos tecidos das glândulas salivares. São necessários mais estudos envolvendo um maior número de pacientes estudados para demonstrar a eficácia dos métodos e modalidades de abordagem distinta.Objectives: To provide basic information on the magnetic resonance imaging modalities, emphasizing the diffusion-weighted imaging technique, as well as to clarify its applicability to diagnose major salivary gland disorders. Methods: The PRISMA statement was used during data assessment and extraction. The MEDLINE (PubMed) database was searched for the period from 2010 to November 2017, for studies providing basic information on the MRI modalities as well its applicability to diagnose salivary gland disorders. Data extraction included information regarding: application of MRI modalities especially ADC and DWI to diagnose major salivary gland disorders. Results: The search yielded 58 publications in MEDLINE (PubMed). The initial screening of the publications was performed using abstracts and keywords. After application of exclusion criteria, we identified a total of 9 studies as eligible to be discussed. Studies revealed two main types of MRI modalities: ADC and DWI. Most of the studies suggest that MRI can be useful as a diagnostic tool for major salivary glands. Conclusion: MRI modalities are advantageous tools for salivary gland tissue evaluations. To demonstrate the accuracy of the distinct approach methods and modalities, more studies involving a larger number of patients studied are necessary

Cone-beam computed tomography analysis of degenerative changes, condylar excursions and positioning and possible correlations with temporomandibular disorder signs and symptoms

Aim: To describe cone-beam computed tomography (CBCT) features in patients with temporomandibular disorders (TMDs), in terms of degenerative changes, condylar excursions and positioning as well as their possible correlations with signs and symptoms. Methods: Clinical records of patients diagnosed with TMD who were seen between January 2018 and December 2019 were retrospectively evaluated. These patients were divided into the following groups based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD): arthralgia, myalgia, and arthralgia and myalgia groups. The CBCT examination findings of the patients were evaluated in relation to degenerative changes, estimates of condylar excursion, and condylar positioning. The likelihood ratio test was used to verify the possible differences among the three groups, whereas the chi-square test was used to verify the possible differences among the signs and symptoms for the tomographic findings (p ≤ 0.050). Results: In this study, 65 patients with TMD were included. These patients were predominantly female (84.6%) with a mean age of 40.6 years. Tomographic findings of flattening, hyperexcursion and posterior condylar positioning were frequent. A significant correlation was noted between osteophyte and lateral capsule pain (p = 0.027), erosion and posterior capsule pain (p = 0.026), and flattening, pseudocysts (p < 0.050) and condylar excursion (p < 0.001) with mouth opening. Conclusion: Few correlations were noted between degenerative changes and signs of joint pain as well as degenerative changes and condylar hypoexcursion with mouth opening. These correlations were likely associated with division by diagnosis, whereas condylar positioning did not correlate with signs and symptoms

Influence of Apical Patency on the Adaptation of the Master Filling Cone: A Cone-beam Computed Tomography Assessment

Introduction: This study aimed to evaluate if the apical patency can influence the adaptation of the master cone of gutta-percha, quantifying the volume of voids and areas at the last 2 mm of the working length (WL). Materials and Methods: Sixty distobuccal canals of extracted upper molars were divided into 3 groups (n=20) based on the patency length (A: passed 1 mm beyond the apical foramen (AF), B: at the AF and C: 1 mm short of the AF) with the Easy ProDesign Logic 25/0.01 file. Each group was subdivided into 2 subgroups (n=10) based on the WL established to prepare the root canal (1: 1 mm short of the AF or 2: at the AF) with the Easy ProDesign Logic 25/0.05 file. After the scan, void volumes were calculated from the last 2 mm of the WL and void areas at 0 mm, 1 mm and 2 mm of the last of WL, as well as the relation between the tip and taper of the master cone with the amount of void volume and areas. To investigate statistically significant differences, we used the Kruskal-Wallis statistical test. Results: There were more voids in volume when patency was achieved 1 mm beyond the AF and the root canal preparation was conducted at 1mm short of the AF (A1 group). Furthermore, the same group showed more voids areas, mainly on the last millimeter of WL. Conclusion: Achieving apical patency at 1 mm beyond the AF followed by instrumentation 1 mm short of the AF created more voids between the master gutta-percha cone and the root canal wall, especially on the last millimeter of WL

Effect of a metal artifact reduction algorithm on dehiscence and fenestration detection around zirconia implants with cone beam computed tomography

Objective. To assess the efficacy of the metal artifact reduction algorithm (MARA) of the Cranex 3D cone beam computed tomography (CBCT) device in the detection of peri-implant dehiscence and fenestration around zirconia implants. Study Design. In total, 60 implants were placed in bovine ribs. Dehiscence and fenestration defects were created around the implants, after which 60 CBCT images were obtained with and 60 without activation of MARA. Three radiologists examined the images for the presence of defects. The area under the curve (AUC) from receiver operating characteristic analysis, sensitivity, and specificity were calculated to assess the ability to discriminate the presence vs absence of bone defects. One-way analysis of variance was employed to analyze outcome measures. The significance level was established at 5% (a = 0.05). Results. AUC values indicated excellent discrimination of dehiscence on images with MARA activation and an excellent to outstanding range of discrimination with MARA deactivation. For fenestration, MARA activation and deactivation both led to outstanding discrimination. Sensitivity and specificity values revealed that activation of MARA was helpful in distinguishing the presence vs. absence of dehiscence, while both MARA conditions were helpful for fenestration. However, there were no statistically significant differences between MARA activation and deactivation for any outcome measure (P >.05). Conclusion. CBCT is suitable for detecting peri-implant defects, but MARA application does not significantly affect peri-implant dehiscence and fenestration detection. (Oral Surg Oral Med Oral Pathol Oral Radiol 2024;138:316-323

Hausdorff Distance evaluation of orthodontic accessories' streaking artifacts in 3D model superimposition

The aim of this study was to determine whether image artifacts caused by orthodontic metal accessories interfere with the accuracy of 3D CBCT model superimposition. A human dry skull was subjected three times to a CBCT scan: at first without orthodontic brackets (T1), then with stainless steel brackets bonded without (T2) and with orthodontic arch wires (T3) inserted into the brackets' slots. The registration of image surfaces and the superimposition of 3D models were performed. Within-subject surface distances between T1-T2, T1-T3 and T2-T3 were computed and calculated for comparison among the three data sets. The minimum and maximum Hausdorff Distance units (HDu) computed between the corresponding data points of the T1 and T2 CBCT 3D surface images were 0.000000 and 0.049280 HDu, respectively, and the mean distance was 0.002497 HDu. The minimum and maximum Hausdorff Distances between T1 and T3 were 0.000000 and 0.047440 HDu, respectively, with a mean distance of 0.002585 HDu. In the comparison between T2 and T3, the minimum, maximum and mean Hausdorff Distances were 0.000000, 0.025616 and 0.000347 HDu, respectively. In the current study, the image artifacts caused by metal orthodontic accessories did not compromise the accuracy of the 3D model superimposition. Color-coded maps of overlaid structures complemented the computed Hausdorff Distances and demonstrated a precise fusion between the data sets

Evaluation of mandibular condyles in children with unilateral posterior crossbite

The relationship of mandibular condyle dimensions and its association with unilateral posterior crossbite (UPXB) has been suggested in the literature. The purpose of this prospective study was to evaluate mandibular condyles on the left and right sides and between crossed and non-crossed sides in the sagittal and coronal planes, using cone-beam computed tomography (CBCT). Twenty CBCT images of 40 temporo mandibular joints (TMJs) in individuals in mixed dentition phase, which included 9 males (mean 7.9 years) and 11 females (mean 8.2 years), with unilateral posterior crossbite without premature contacts and functional mandibular shifts and with transverse maxillary deficiency. The criteria for sample exclusion included the presence of painful symptoms, facial trauma history, systemic diseases such as juvenile rheumatoid arthritis, mouth opening limitation (< 40 mm), congenital or genetic anomalies, and skeletal asymmetries that may result in TMJ disorders. Dimensional measurements of the condyles between the right and left sides and crossed and non-crossed sides in sagittal and coronal view were made. There was no significant difference between the measurements of the crossed and non-crossed sides in both sagittal and coronal view. These findings suggest that the presence of unilateral posterior crossbite in children with UPXB did not result in changes between the mandibular condyles in the right and left sides or between the crossed and non-crossed sides in the coronal or sagittal plane

Assessment of Peri-implant Buccal Bone Thickness Using Digital Imaging Techniques: A Systematic Review and Meta-analysis

Objectives: This systematic review aimed to answer the following focused question: Do the currently available imaging techniques provide accuracy in the assessment of peri-implant buccal bone thickness? Methods: A search strategy was conducted in eight electronic databases, followed by an additional manual search in grey literature and references of selected articles. Studies evaluating the accuracy of imaging techniques to measure peri-implant buccal bone thickness were included. Individual risk of bias was assessed by the Quality Assessment Tool for Diagnostic Accuracy Studies-2 (QUADAS-2). Meta-analysis was performed to evaluate CBCT accuracy. The overall effect size was determined by means of the Z-test. Q test was used to evaluate the homogeneity of effect sizes among studies and I2 was applied to determine the variance within studies. Results: After an initial screening, 83 studies were further selected for full reading and 13 of them were considered eligible for this review. In sum, the accuracy of Cone-beam Computed Tomography (CBCT), of ultrasound, and of computed tomography were assessed. There was no statistically significant difference between CBCT and the gold standard (p=0.81). The mean difference between measurements of bone thickness obtained by CBCT and the goldstandard was -0.0.3mm [95%CI -0.29;0.253mm]. Conclusion: CBCT showed acceptable accuracy for assessing peri-implant bone. No meaningful conclusion could be drawn about other techniques. </jats:sec

Assessment of the Mandibular Incisive Canal by Panoramic Radiograph and Cone-Beam Computed Tomography

Objectives. The region between mental foramens is considered as a zone of choice for implants. However, complications may arise due to an extension anterior to the mental foramen that forms the mandible incisive canal [MIC]. Our goal is to evaluate identification of MIC by both panoramic radiograph [PAN] and cone-beam computed tomography [CBCT]. Methods. 150 cases with bilateral MIC were analyzed. Images of a radiolucent canal, within the trabecular bone, surrounded by a radiopaque cortical bone representing the canal walls, and extending to the anterior portion beyond the mental foramen, were considered by two independent radiologists as being images of MIC. PAN and CBCT of these cases were evaluated by 2 other radiologists at different times. Agreement between results of examination methods was assessed by the Kappa coefficient. The interexaminer and intramethod rates for detection of MIC were analyzed by the McNemar test. Gender, mandible side, examiner, and type of method were analyzed by the generalized estimating equations [GEE] model. Results. significant difference between examiners [PAN:  P=0.146; CBCT: P=0.749] was not observed. Analysis by GEE model showed no significant difference between genders [P=0.411] and examiners [P=0.183]. However, significant difference was observed for identification in both mandible right side [P=0.001], where the identification frequency was higher, and CBCT method [P<0.001]. Conclusions. PAN was not shown to be a safe examination to identify MIC. CBCT should always be used in preoperative planning and to reduce the number of complications in implant surgeries