Diagnosis of Mesiodistal Vertical Root Fractures in Teeth with Metal Posts: Influence of Applying Filters in Cone-beam Computed Tomography Images at Different Resolutions.

INTRODUCTION: The aim of this article was to evaluate the influence of applying filters in cone-beam computed tomography (CBCT) images at different resolutions. These CBCT images were obtained for diagnosing mesiodistal vertical root fractures (VRFs) in teeth with metal posts. METHODS: Forty teeth were treated endodontically, and 20 received metal posts. Ten teeth without posts and 10 teeth with posts were subjected to VRF in the mesiodistal direction. The sample was submitted to periapical radiographs and CBCT exams with a voxel of 0.25 and 0.30 mm. To reduce the influence of the metal artifact in the CT images, the teeth were evaluated with and without the application of filters ("Sharpen" and "Hard"). The images were evaluated by 2 radiologists who identified the presence of VRF. Accuracy values (receiver operating characteristic curves) for the different variables were compared by using analysis of variance and t test. RESULTS: No difference was observed between images with and without filter application (P > .05). Images obtained with a 0.25-mm voxel were more accurate (P < .05). The presence of the metal post reduced the accuracy of the diagnosis of VRF (P < .05), and the CBCT images showed superior results compared with periapical radiographs (P < .05). CONCLUSIONS: The presence of a metal post and the voxel size significantly interfere with the diagnosis of VRF. Despite the formation of metal artifacts associated with metallic cores, applying filters did not improve the diagnosis. For mesiodistal VRF, the CBCT images are superior to the periapical radiographs.

Influence of lip retraction on the cone beam computed tomography assessment of bone and gingival tissues of the anterior maxilla.

OBJECTIVE: To evaluate the influence of lip retraction on cone beam computed tomography (CBCT) assessment of bone and gingival tissues on the labial surface of the anterior maxilla. STUDY DESIGN: A retrospective study was conducted using measurements of bone and gingival tissues collected from 120 maxillary incisors. The thicknesses of the bone and gingival tissues of different regions were measured on CBCT images, with and without a lip retractor. The thicknesses of the gingival tissues obtained from CBCT were correlated with measurements performed by clinical probing. RESULTS: The thickness of bone in the more cervical region presented a higher mean value for exams performed with a lip retractor (P = .021). The thickness of bone found a significant correlation with the thickness of the gingiva (P ≤ .020) with a lip retractor in CBCT exams. The thickness of the gingival tissue obtained from CBCT scans with lip retraction found significant correlations with those obtained clinically (P ≤ .001). CONCLUSIONS: The use of lip retractors is a simple and reliable practice that allows the measurement of gingival tissues on CBCT images. This practice can exempt a patient from an invasive clinical procedure for measuring the thickness of the gingival tissue for implant cases of the anterior segment.

Assessment of mandibular posterior regional landmarks using cone-beam computed tomography in dental implant surgery.

The aim of this study has been to evaluate and correlate the anatomical features of the posterior mandibular region (submandibular fossa depth, bone height and thickness, and mandibular canal corticalization) to improve accident prevention and allow safe planning in implantology. Four parasagittal sections of cone-beam computed tomography (CBCT) from 100 patients were bilaterally analyzed. Linear measurements of the submandibular fossa depth, bone height and thickness were performed. The submandibular fossa was also classified into non-influential undercuts and influential undercuts for implant placement. Mandibular canal corticalization was also evaluated and classified according to the visualization. Data on patient age and gender were also collected. Forty-one scans (41%) were from male patients, and 59 (59%) were from female patients. Patient age ranged between 18 and 84 years, with an average age of 51.37 years. The submandibular fossa depth and implant bone thickness had a significant effect on the variability of the sample (46.1% and 22.3%, respectively). The submandibular fossa depth was quite variable, and the highest values were observed in the posterior regions. In 18.27% of the cases, the presence of the fossa directly influenced implant placement, considering a bone height of 10mm (standard implant). A significant correlation was observed between fossa depth and bone thickness. Thus, greater attention should be paid to thick ridges; although thick ridges are favorable, they may be associated with deeper submandibular fossae. The mandibular canal was the most influential anatomical structure in the premolar region due to the reduced bone height in this region and the greater difficulty in viewing the canal, and the submandibular fossa was the most influential structure in the molar region due to lower bone height leading up to the fossa and the greater fossa depth in this region. Therefore, CBCT is an important tool for assessing the mandibular region and planning for safe implant installation in the posterior mandible. Furthermore, comprehensive evaluation of the characteristics of this region is necessary, as the variables - submandibular fossa depth, bone height and thickness, and mandibular canal corticalization - are related and must be considered together when planning.

Intraobserver and interobserver agreement of Goutallier classification applied to magnetic resonance images.

BACKGROUND: Fatty infiltration of the muscle bellies is an important prognostic factor in rotator cuff tears. It was described initially in computed tomography examinations, and there is an ongoing debate about whether magnetic resonance (MR) is a reliable method for staging fatty infiltration. This study sought to determine intraobserver and interobserver agreement for Goutallier's classification of fatty infiltration of the rotator cuff as evaluated through MR imaging. MATERIALS AND METHODS: Twenty MR examinations of the shoulder showing full-thickness tear of the supraspinatus tendon, with or without associated lesions, were evaluated by 3 radiologists with experience in musculoskeletal system imaging and 3 fellowship-trained shoulder surgeons. The evaluators classified the fatty infiltration of the supraspinatus muscle according to the guidelines proposed by Goutallier et al. After 8 weeks, they re-evaluated the examinations, without access to their previous reports. Weighted κ index values were determined for intraobserver and interobserver agreement analyses, and intraobserver agreement κ values are reported with 95% confidence intervals (CIs). RESULTS: The mean intraobserver agreement was 0.832 among the orthopedists (CI > 95%) and 0.741 among the radiologists (CI > 95%). Interobserver agreement was 0.8214 (evaluation 1) and 0.7231 (evaluation 2) among the orthopedists (P < .0001) and 0.6627 (evaluation 1) and 0.6067 (evaluation 2) among the radiologists (P < .0001). Intraobserver agreement was not associated with length of experience or frequency of routine evaluations. CONCLUSIONS: When it is applied to MR images of rotator cuff musculature, Goutallier's fatty infiltration staging rubric yielded highly significant intraobserver and interobserver agreement.

Estudio radiográfico de las alteraciones morfológicas de la apófisis estiloide y de la rotación del cóndilo mandibular en pacientes con desorden temporomandibular / Radiographic study of the morphological variations of the styloid process and of the condylar excursion in patients with temporomandibular disorder

En este estudio se evaluó radiográficamente en pacientes con desorden temporomandibular la posible relación entre las alteraciones morfológicas de la apófisis estiloide del hueso temporal y el patrón de rotación mandibular. Fueron analizadas 1500 radiografías convencionales de las articulaciones temporomandibulares de los archivos del Servicio-ATM - Facultad de Odontología de la Universidad Federal de Juiz de Fora. Se observó que 83 pacientes (5,53%) presentaron al menos una de las apófisis estiloide alterada morfológicamente, siendo 9 (10,8%) del sexo masculino y 74 (89,2%) del sexo femenino. La mayoría de los pacientes de este grupo se ubica entre 41 a 50 años de edad (32,5%). Los tipos morfológicos fueron clasificados en normal (13), alargados (113), seudoarticulado (21) y segmentado (19), totalizando 166 apófisis estiloide. La clasificación de la rotación condilar encontrada fue: normal (47), hipomovilidad condilar (30) y hipermovilidad condilar (89), totalizando 166 articulaciones temporomandibulares. Por el método estadístico de Cramer`s no fueron verificados indicios de relación de que las alteraciones morfológicas de la apófisis estiloide pueden interferir en la rotación del cóndilo mandibular ni relación de simetría entre los lados derecho e izquierdo, tanto para el tipo morfológico como para la rotación condilar.

The aim of this study was to assess radiographically the possible relations between the morphological variations of the styloid process of the temporal bone and the pattern of the condylar excursions in patients with temporomandibular disorders. 1500 conventional x-rays of temporomandibular joints were analyzed, all of them from the SERVIÇO-ATM-FO/UFJF files. The results show that 83 patients (5.53%) had at least one morphologic variation of the styloid process, among which 09 (10.8%) were male and 74 (89.2%) female. Most of these patients are included in the age group of 41 to 50 years (32.5%). The morphological types were classified as normal (13), elongated (113), pseudoarticulated (21) and segmented (19), totalizing 166 styloid processes. The classification of the condylar excursion was normal (47), condylar hypomobility (30) and condylar hypermobility (89), which totals 166 temporomandibular joints. According to Cramer’s V statistic method, evidences that styloid process variations may interfere in the condylar excursion were not found; there is symmetry between the left and right sides concerning both morphological type and condylar excursion.