Iêda Crusoé-Rebello

Canalis sinuosus: a rare anatomical variation

The infraorbital canal issues a small branch on its lateral face close to its midpoint to allow passage of the anterior superior alveolar nerve. This small canal, sometimes called the canalis sinuosus, runs forward and downward to the inferior wall of the orbit, lateral to the infraorbital canal and medially bent to the anterior wall of the maxillary sinus, passing below the infraorbital foramen. Anatomical variations in the maxilla are rarely described in the literature and, in most cases, are related to the nasopalatine canal. This article describes a rare anatomical variation of the presence of a bilateral accessory canal extending from the nasal cavity lateral wall to an accessory foramen located on the hard palate, adjacent to the maxillary lateral incisor observed in cone beam computed tomography (CBCT) images. This case is an anatomical variation of the anterior superior alveolar nerve (canalis sinuosus). Identification of individual anatomical variations, especially on CBCT, may help the surgeon to avoid injuries to nerves during implant placement.

Rare anatomical variation related to the nasopalatine canal

The nasopalatine canal is a relatively long narrow structure located in the midline of the maxilla that contains the nasopalatine nerve and terminal branch of the descending palatine artery. Anatomical variations related to this structure have been reported. This article aimed to report a case of a complete additional nasopalatine canal on a 53-year-old female patient who underwent an examination by cone beam computed tomography. On sagittal slices, it was possible to observe the presence of an additional canal anterior and superior to the nasopalatine canal, separated by a bony septum. Each canal extended from independent superior openings (located in the nasal cavity) to independent openings located in the remaining alveolar process of the anterior maxilla. Identification of individual anatomical variations, especially involving neurovascular structures, plays an important role in the successful outcomes of surgical procedures involving the anterior maxilla.

Prevalence of Supernumerary Teeth in Orthodontic Patients from Southwestern Brazil

El objetivo de este estudio fue investigar la prevalencia de dientes supernumerarios en una poblacion pediatrica de Brasil. Un examinador evaluo la presencia de dientes supernumerarios en radiografias panoramicas de 1719 sujetos (762 hombres y 957 mujeres), con edades comprendidas entre 4 y 14,5 anos (media 8,4 anos de edad), del archivo del Curso de Ortodoncia Preventiva del Hospital de Rehabilitacion de Bauru, Sao Paulo. Los dientes supernumerarios se presentaron en treinta sujetos (1,7%, 16 hombres y 14 mujeres). La diferencia entre sexos no fue estadisticamente significativa. Veintinueve dientes supernumerarios (96,7%) se ubicaron en el maxilar, y solo 1 (3,3%) se ubico en la mandibula. Diecisiete dientes supernumerarios (56,7%) ubicados en el maxilar eran mesiodens. El diagnostico precoz de los dientes supernumerarios es esencial para prevenir la maloclusion y malposicion de los dientes permanentes, lo que demuestra la importancia de la radiografia panoramica en su deteccion.

Temporomandibular Joint Disc Adhesion Without Mouth-Opening Limitation

We present a case of a 26-year-old female patient complaining of articular pain and clicking on the left side, caused by mastication, of 5 years’ duration. Clinically, the patient presented with jaw-opening limitation, with deflection of the mandible to the right side without correction of the trajectory at the end of the jaw-opening movement. Imaging studies led to a diagnosis of bilateral disk adhesion (anchored disc phenomenon [ADP]) and slight limitation of the right condyle translation. This case, likely the first to be reported in the literature, confirms that reciprocal clicking may occur in cases of ADP and that, contrary to the general concept, ADP without mouth-opening limitation can occasionally occur.

Assessment of enamel-dentin caries lesions detection using bitewing PSP digital images

Objectives The aim of this study was to evaluate the detection of enamel-dentin occlusal caries using photostimulable phosphor plates. Material and Methods The ability to detect enamel-dentin occlusal caries in 607 premolars and molars from 47 patients between 10 and 18 years old, referred to the School of Dentistry of the Federal University of Bahia, Brazil, was evaluated based on clinical and radiographic examinations, using the criteria proposed in a previous study. A total of 156 bitewing digital images were obtained using Digora® (Soredex Medical Systems, Helsinki, Finland) phosphor plates. The plates were scanned and the images were captured and displayed on a computer screen. Image evaluation was done using Digora® for Windows 2.1 software, Soredex®. The radiologists were allowed to use enhancement tools to obtain better visibility during scoring of the teeth based on the radiographic criteria proposed in a previous study. Descriptive analysis and chi-squared proportion tests were done at 5% significance level. Results The results of clinical examination showed a higher prevalence of teeth with a straight dark line or demineralization of the occlusal fissure (score 1) and a lower prevalence of sealed teeth (score 5). In the bitewing digital images, 47 teeth presented visible radiolucency, circumscribed, in dentin under occlusal enamel (enamel-dentin caries lesions). Conclusions Correlating the clinical and radiographic findings, it was found that in the majority of teeth diagnosed by radiographic images as having enamel-dentin caries, no caries could be detected by clinical examination.

Avaliação de doses referenciais obtidas com exames de tomografia computadorizada de feixe cônico adquiridos com diferentes tamanhos de voxel

Objectives: The aim of this study was to evaluate the dose–area product (DAP) and the entrance skin dose (ESD), using protocols with different voxel sizes, obtained with i-CAT Cone-Beam Computed Tomography (CBCT), to determine the best parameters based on radioprotection principles. Methods: A pencil-type ionization chamber was used to measure the ESD and a PTW device was used to measure the DAP. Four protocols were tested: (1) 40s, 0.2 mm voxel and 46.72 mAs; (2) 40s, 0.25 mm voxel and 46.72 mAs; (3) 20s, 0.3 mm voxel and 23.87 mAs; (4) 20s, 0.4 mm voxel and 23.87 mAs. The kilovoltage remained constant (120 kVp). Results: A significant statistical difference (p<0.001) was found among the four protocols for both methods of radiation dosage evaluation (DAP and ESD). For DAP evaluation, protocols 2 and 3 presented a statistically significant difference, and it was not possible to detect which of the protocols for ESD evaluation promoted this result. Conclusions: DAP and ESD are evaluation methods for radiation dose for Cone-Beam Computed Tomography, and more studies are necessary to explain such result. The voxel size alone does not affect the radiation dose in CBCT (i-CAT) examinations. The radiation dose for CBCT (i-CAT) examinations is directly related to the exposure time and milliamperes.OBJETIVO: o objetivo deste estudo reside na avaliacao do produto dose-area (DAP) e das doses de entrada na pele (DEP), empregando protocolos com tamanho de voxel diferente, obtidos com o aparelho de Tomografia Computadorizada de Feixe Conico (TCFC) i-CAT, a fim de determinar melhores parâmetros baseados nos principios da radioprotecao. METODOS: para medicao do DEP foi utilizada uma câmara de ionizacao do tipo lapis, e para o DAP foi utilizado um aparelho PTW. Quatro protocolos foram testados, a saber: (1) 40 seg., voxel de 0,2mm e 46,72mAs; (2) 40 seg., voxel de 0,25mm e 46,72mAs; (3) 20 seg., voxel de 0,3mm e 23,87mAs; (4) 20 seg., voxel de 0,4mm e 23,87mAs. A quilovoltagem permaneceu constante (120KVp). RESULTADOS: detectou-se diferenca estatisticamente significativa (p<0,001) entre os quatro protocolos, para os dois metodos de avaliacao da dose de radiacao (DAP e DEP). Na avaliacao do DAP, os protocolos 2 e 3 promoveram uma diferenca estatisticamente significativa, nao sendo possivel detectar qual dos protocolos na avaliacao da DEP proporcionou esse resultado. CONCLUSAO: DAP e DEP apresentam-se como metodos de avaliacao para doses de radiacao em tomografia computadorizada de feixe conico, sendo necessarios mais estudos para elucidar tal achado. O tamanho do voxel, isoladamente, nao e capaz de interferir na dose de radiacao em exames de TCFC (i-CAT). A dose de radiacao para exames de TCFC (i-CAT) esta diretamente relacionada ao tempo de exposicao e a miliamperagem.

Assessment of computerized tomography density patterns of ameloblastomas and keratocystic odontogenic tumors

The aim of this study was to evaluate computerized tomography (CT) density patterns of solid ameloblastomas (SA), unicystic ameloblastomas (UA), and sporadic and multiple keratocystic odontogenic tumors (SK and MK, respectively). A region of interest (ROI) was delimited corresponding to almost the entire lesional area on each axial slice of 25 CT exams. For each ROI, CT values (HU(ROI)) and heterogeneity (HTG(ROI)) were recorded and compared among lesion groups as well as among central and peripheral slices of the same lesion. The average HU(ROI) were: SA 35.9 +/- 12.6; UA 31.0 +/- 6.0; SK 28.4 +/- 10.5; and MK 30.5 +/- 20.6. SK and MK had the lowest CT values and highest heterogeneity. SA and UA did not show statistical difference for HU(ROI). However, SA had greater HTG(ROI) values. SA presented a different pattern when the central slices were compared with the peripheral slices. HU(ROI) was higher, whereas HTG(ROI) was lower, among the central slices of SA.

Uncommon dentigerous cyst related to a maxillary lateral incisor in a 03-year-old boy

BackgroundThe dentigerous cyst is usually defined as a cystic cavity that surrounds the crown of an unerupted tooth on the cementoenamel junction. The present article reports a case of an uncommon dentigerous cyst, highlighting its clinical, radiographic and surgical characteristics and discussing the aspects related to its development in infancy.Case reportA 03-year-old boy patient presented with an extensive radiolucid area involving the crown of the right maxillary lateral incisor. A surgical excision was performed. Anatomopathological examination revealed a cystic tissue with a fibrous wall surrounded by nonkeratinized stratified squamous oral epithelium, without atypia.ConclusionIt is possible that the dentigerous cyst grows in the dental germ in any stage of development and not only in the follicle of a tooth with calcified crown attached to the cementoenamel junction.

Correlation between maxillofacial radiographic features and systemic severity as sickle cell disease severity predictor.

This study was conducted to investigate the relationship among radiographic features observed on panoramic radiographs of sickle cell disease patients and analyze their relationship with history of systemic severity of the disease. Panoramic radiographs of 71 subjects with sickle cell disease were evaluated for the presence of the following radiographic bony alterations: radiopaque areas, increased spacing of bony trabeculae, horizontal arrangement of bony trabeculae and corticalization of mandibular canal. History of clinical systemic severity was assessed through direct questioning about the frequency of vaso-occlusive crisis, history of stroke, clinical jaundice, femur head necrosis, and leg ulceration. Chi-square or Fisher’s exact test were applied in order to analyze possible associations between radiographic features and history of complications, with p < 0.05 significance level. Increased spacing of bony trabeculae was statistically associated with absence of corticalization of mandibular canal (p < 0.01) and horizontal arrangement of bony trabeculae (p = 0.04). Statistically significant associations were demonstrated between history of clinical jaundice and presence of increased spacing of bony trabeculae (p = 0.02) and between history of stroke and presence of horizontal arrangement of bony trabeculae (p = 0.04). Based on the results of the current study, maxillofacial radiographic features may be associated with clinical parameters of systemic complications in sickle cell disease patients. The relationship between radiographic features and history of complications associated with clinical severity of sickle cell disease has not been demonstrated in the literature. Acknowledgment of such possible association may help establish prognosis and influence clinical treatment of systemic and oral complications.

Radiographic changes of the jaws in HbSS and HbSC genotypes of sickle cell disease

This study used panoramic radiographs to evaluate the presence of radiographic changes in the jaws of a population who had sickle cell disease (SCD). The authors compared the frequency of findings between subjects with and without SCD. Panoramic radiographs of 71 subjects with SCD (36 with HbSS and 35 with HbSC) and 52 healthy controls (HbAA) were evaluated for the presence of the following radiographic alterations: radiopaque areas, increased spacing of bony trabeculae, horizontal arrangement of bony trabeculae, and absence of mandibular canal corticalization. The control group had a significantly smaller number of all the radiographic features evaluated. Differences were not statistically significant between the groups with HbSS and HbSC, except for more trabecular spacing in the molar region in the HbSS genotype, suggesting a possible correlation between radiographic findings and disease presentation.