Convenient model of hard tissue simulation for dental radiographic research and instruction.

BACKGROUND: The authors describe a technique for building an alternative jawbone phantom using dental gypsum and rice for research and dental radiology instruction. AIM: To investigate the potential of an alternative phantom to simulate the trabecular bone aspect of the human maxilla in periapical radiographs. METHODS: Half-maxillary phantoms built from gypsum-ground rice were exposed to X-rays, and the resulting images (experimental group) were compared to standardized radiographic images produced from dry human maxillary bone (control group) (n = 7). The images were blindly assessed according to strict criteria by three examiners for the usual trabecular aspects of the surrounding bone, and significant differences between groups and in assessment reliability were compared using Fisher's exact and kappa tests (α = 0.05). RESULTS: The differences in the trabecular aspects between groups were not statistically significant. In addition, interobserver agreement among observers was 0.43 and 0.51 for the control and experimental groups, respectively, whereas intraobserver agreement was 0.71 and 0.73, respectively. CONCLUSION: The tested phantom seemed to demonstrate potential for trabecular bone image simulation on maxillary periapical radiographs.

Evaluation of the Nasopalatine Canal of Patients With and Without Cleft Lip and Palate in CBCT Exams.

OBJECTIVE: To identify and compare the morphology and dimensions of the nasopalatine canal (NPC) of individuals with and without cleft lip and palate using Conical Beam Computed Tomography (CBCT) images and to relate the results to the type of cleft and tooth absences in the region. SETTING: This is a cross-sectional, analytical study with a retrospective sample. PATIENTS, PARTICIPANTS: 100 CBCT exams from patients with cleft lip and palate and 100 CBCT exams from patients without cleft lip and palate were used. INTERVENTIONS: The NPC was evaluated for its morphology and measurements in the coronal, sagittal, and axial reformatting of CBCT exams. RESULTS: It was obtained as a result that in the group of patients with a cleft, the shapes of funnel, banana, and needle of the NPC were more frequent than in the control group. Patients with cleft lip and palate had significantly a larger nasopalatine foramen and a larger NPC diameter, besides a significantly shorter NPC, compared to controls. In both groups, edentulous patients had less anterior maxillary bone thickness, when compared to patients with maxillary anterior teeth. Patients with clefts had a bone thickness buccal to the NPC less than in the control group. CONCLUSIONS: This study confirms the anatomical variability of NPC in patients with cleft lip and palate. This finding reinforces the need for thorough surgical planning of the anterior region of the maxilla, in CBCT exams, by the dentist.

The impact of medication-related osteonecrosis of the jaws on the quality of life in cancer patients.

BACKGROUND: To evaluate the impact of oral health on the quality of life (QOL) of individuals undergoing cancer treatment at the time of diagnosis of medication-related osteonecrosis of the jaw (MRONJ). MATERIAL AND METHODS: The present cross-sectional study analyzed patients with MRONJ from 2013 to 2019. The collected data included demographic data, base disease, medications associated with MRONJ, route of administration and time of use, signs, symptoms, and tomographic features of acute MRONJ, staging according to American Association of Oral and maxillofacial Surgeons position paper 2014 (AAOMS), type of dental treatment performed, outcome, and the responses to the Oral Health Impact Profile questionnaire (OHIP-14). Statistical analysis was performed using the Tukey test to study the association between oral condition and the QOL. A p-value of less than 0.05 was considered statistically significant. RESULTS: The sample consisted of 16 medical records of patients with MRONJ. Psychological discomfort showed alarmingly significant results (p< 0.001) with strong negative impact on the QOL of the patients. Functional limitation was the least affected dimension (p = 0.747). The other dimensions did not show statistically significant results. CONCLUSIONS: MRONJ compromises oral health and negatively impacts the QOL, especially with respect to the psychological discomfort (worry and stress). The OHIP-14 questionnaire proved to be an effective tool in the assessment of this impact. Key words:Medication-related osteonecrosis of the jaw, quality of life, oral health, OHIP-14.

Study Between Panoramic Radiography and Cone Beam-Computed Tomography in the Diagnosis of Ameloblastoma, Odontogenic Keratocyst, and Dentigerous Cyst.

OBJECTIVE: To determine how the diagnosis may or may not be influenced by cone-beam computed tomography (CBCT), comparing the diagnostic hypotheses obtained using images of panoramic radiographs and CBCT in cases of ameloblastoma, odontogenic keratocyst, and dentigerous cyst. STUDY DESIGN: Five cases were selected for each lesion. Panoramic radiographs and CBCT scans were analyzed by 15 dentists for the formulation of the diagnostic hypotheses. Two observers performed the analyses and measurement of qualitative and quantitative features of the lesions evaluated in the CBCT. RESULTS: There was no statistically significant difference in correct diagnostic average between panoramic radiography and CBCT, but there was a significant difference in correct diagnostic average in the diagnosis of ameloblastoma using CBCT compared to panoramic radiography. Master's and PhD-level observers had greater correct diagnostic average in the diagnosis of odontogenic keratocyst using panoramic radiograph compared to specialists, with a significant difference. CONCLUSION: Cone-beam computed tomography images revealed that the ameloblastomas were greater in size and expansion compared to the odontogenic keratocyst and the dentigerous cysts. Ameloblastomas showed a higher incidence of multiloculated aspects compared to odontogenic keratocyst and dentigerous cysts. There were no differences between quantitative and qualitative features of odontogenic keratocyst and dentigerous cysts.

A case-control study of dental abnormalities and dental maturity in childhood cancer survivors.

OBJECTIVE: The aim of this study was to evaluate dental abnormalities and dental maturity (DM) in the permanent dentition of childhood cancer survivors (CCSs) in comparison with that of healthy individuals. STUDY DESIGN: A retrospective, case-control study, with convenience sampling, evaluated 111 panoramic radiographs (PRs) of CCSs compared with 111 PRs of healthy individuals matched for age and gender. Dental anomalies (DAs) were associated with age of cancer diagnosis and type of antineoplastic treatment. DM was assessed by using the Demirjian method. RESULTS: A higher prevalence of microdontia, hypodontia, and dental root anomalies were present in CCSs compared with healthy individuals (P < .05). CCSs were the only individuals with 10 or greater DAs compared with healthy individuals. Microdontia was the only DA associated with age of cancer diagnosis less than 71 months (P < .05). Impacted teeth were associated with multimodal cancer treatment (P < .001). DM did not present a significant statistical difference between CCSs and healthy individuals (P > .05). CONCLUSIONS: CCSs had a higher prevalence of DAs without DM alteration compared with healthy individuals. Age of cancer diagnosis and type of treatment can influence the prevalence of some dental abnormalities.

Conservative Treatment of Chronic Osteomyelitis Associated with Florid Osseous Dysplasia / Tratamiento Conservador de la Osteomielitis Crónica Asociada con Displasia Ósea Florida

ABSTRACT: Florid osseous dysplasia (FOD) is an extensive form of osseous dysplasia where normal trabecular bone is substituted by fibrous connective tissue and amorphous mineralized tissue. Usually, the lesions are mainly asymptomatic and the patients should be followed with clinical and imaging examination, requiring no intervention. Nevertheless, due to the poor vascularization of the lesion and to local trauma, secondary infections and osteomyelitis may occur. Patients may present with pain, mucosal ulceration, lesion exposure in the oral cavity, fistula and swelling. In such cases, the correct diagnosis and management of the lesion is decisive to reestablish patient's health and quality of life. The aim of this article is to present a case of complicating secondary chronic osteomyelitis treated successfully with conservative intervention. A 68-year-old black female patient reported a "swelling of the gums" that was present for eleven years, with episodes of periodic pain and swelling. On physical examination, a papule with suppuration in the alveolar mucosa in the right side of the mandible was observed. Panoramic radiography and CBCT showed a mixed lesion surrounded by sclerotic bone. The patient was diagnosed with chronic osteomyelitis in association with FOD and treated with antibiotic therapy together with surgical curettage. The incidence, etiophatology, differential diagnosis, treatment and prevention of secondary osteomyelitis associated with FOD are discussed in the light of literature. This information might assist the dentists while choosing the best treatment options for similar cases.

RESUMEN: La displasia ósea florida (DOF) es una forma de displasia ósea donde el hueso trabecular normal es sustituido por tejido conectivo fibroso y tejido mineralizado amorfo. En general, las lesiones son de origen asintomático y los pacientes deben ser seguidos con el examen clínico. Sin embargo, debido a la pobre vascularización de la lesión y al trauma local, pueden producirse lesiones secundarias y osteomielitis. Los pacientes pueden presentarse con dolor, ulceración mucosa, lesión de exposición en la cavidad oral, fístula y edema. En estos casos, el correcto diagnóstico y tratamiento de la lesión es decisivo para reestabilizar la salud y la calidad de la vida. El objetivo de este artículo consistió en presentar un caso de complicación secundaria crónica de osteomielitis tratados con tratamiento conservador. El paciente, negro, de 68 años de edad, consulta por "hinchazón de las encías" que se presentó durante once años, con episodios de dolor. En el examen intraoral, se observó una pápula con supuración en la mucosa alveolar en el lado derecho de la mandíbula. La radiografía panorámica y CBCT mostraron una lesión mixta rodeada de hueso esclerótico. El paciente fue diagnosticado con osteomielitis crónica en asociación con DOF y fue tratado con tratamiento antibiótico junto con curetaje quirúrgico. La incidencia, la etiopatología, el diagnóstico diferencial, el tratamiento y la prevención de la osteomielitis secundaria asociada con DOF se discuten a la luz de la literatura. Esta información puede ayudar a los dentistas a elegir las mejores opciones de tratamiento para casos similares.

Influence of scan mode (partial/full rotations) and FOV size in the formation of artefacts in cone beam CT.

OBJECTIVE: To evaluate the influence of rotation degree and field of view (FOV) size on the amount of artefacts produced in cone beam CT (CBCT) images. METHODS: A cylindrical wax utility phantom, with a metallic sample in its interior, was scanned with two FOV sizes (100 x 100 and 40 x 40 mm) and in full (360°) and partial (~180°) rotations. After the acquisitions, images were objectively assessed in the ImageJ software, obtaining the standard deviation in areas around the metal sample. The influence of artefacts produced by the several FOVs and rotation degrees was compared by two-way analysis of variance (α = 0.05). RESULTS: The images obtained with a large FOV presented a higher amount of noise compared to a restricted FOV, both for partial (p = 0.0037) and full (p = 0.0023) rotation degrees. For images obtained with a restricted FOV, full rotation resulted in images with less noise (p = 0.0259). For images obtained with large FOV, there was no statistically significant difference (p = 0.1494) in noise for both rotation protocols. CONCLUSIONS: As there were no significant differences in the amount of artefacts in rotation protocols for large FOVs, the partial rotation can be indicated due to its lower exposure to radiation. For acquiring images with restricted FOVs, the full rotation is recommended.

Levantamento de seio maxilar atraumático sem enxertia óssea: uma revisão integrativa / Atraumatic maxillary sinus augmentation without bone grafting: an integrative review

Objetivo: avaliar a eficácia do levantamento do seio maxilar atraumático sem enxerto ósseo e a taxa de sobrevivência da instalação de implantes imediatos. Material e métodos: realizou-se uma estratégia de busca nas bases de dados Pubmed, Web of Science e Science Direct, obtendo 103 artigos, sendo selecionados 07 estudos publicados entre 2008 até 2019. Resultados: foram registrados 576 pacientes com idades entre 19 e 85 anos de idade, de ambos os sexos e 1,113 implantes instalados. Verificou-se uma taxa de sucesso e sobrevivência dos implantes de 96,6%, após um seguimento de 1 a 3 anos e houve um ganho ósseo de aproximadamente 3mm. Considerações finais: o levantamento de seio maxilar atraumático sem enxerto ósseo é eficaz para reabilitação de áreas edêntulas e mostra um bom resultado ao longo do tempo, com uma taxa média de sobrevivência dos implantes de 96,3%. Ainda faltam estudos para determinar qual tipo de implante é melhor para este tipo de técnica. (AU)

Objective: To assess the efficacy of atraumatic maxillary sinus augmentation without bone grafting and the survival rate of the immediate implant installation. Material and methods: A search strategy was performed the in Pubmed, Web of Science, and Science Direct databases, resulting in 103 articles from which seven studies published between 2008 and 2019 were selected. Results: 576 patients of both sexes, aged between 19 and 85 years, were registered, as well as 1,113 implants installed. There was a success rate and survival of implants of 96.6% after a follow-up of 1 to 3 years and there was a bone gain of approximately 3 mm. Final considerations: The atraumatic maxillary sinus augmentation without bone graft is effective to rehabilitate edentulous areas and shows a good outcome over time, with an average rate of implant survival 96.3%. Further studies are still required to determine which type of implant is best for this type of technique.(AU)

Alveolodental ankylosis: biological bases and diagnostic criteria / Anquilose alveolodentária: bases biológicas e critérios para o diagnóstico

ABSTRACT Alveolodental ankylosis is the fusion of cementum or root dentin with the alveolar bone in both deciduous and permanent teeth. This leads to important clinical and radiographic changes in the affected teeth. Moreover, knowledge of the biological principles involved allows adequate management of teeth affected by this phenomenon.

RESUMO A anquilose alveolodentária consiste na fusão do cemento ou dentina radicular com o osso alveolar tanto em dentes decíduos como nos dentes permanentes. Isto leva a uma série de alterações clínicas e radiográficas importantes para o diagnóstico. Além disso, o conhecimento dos princípios biológicos envolvidos irá permitir o controle adequado dos dentes acometidos por este fenômeno.

Interpretação das imagens em tomografia computadoriza de feixe cônico / Reading and interpreting CBCT imaging

Introdução: a tomografia computadorizada de feixe cônico (TCFC) é uma ferramenta auxiliar e complementar de diagnóstico muito presente na prática clínica odontológica; porém, as tecnologias nela envolvidas requerem conhecimento e treinamento do cirurgião-dentista. Objetivo: este artigo aborda os conceitos básicos que regem a TCFC, os artefatos de imagem que comprometem a qualidade do exame, além de elucidar as ferramentas básicas para manipulação das imagens. Métodos: foi realizada uma revisão por meio de busca na base de dados PubMed, que encontrou 19 artigos publicados de 2008 a 2016. Resultados: é apresentada uma maneira otimizada de avaliação de todo o volume da imagem, bem como as principais alterações encontradas em cada região. (AU)

Zoom Reconstruction Tool: Evaluation of Image Quality and Influence on the Diagnosis of Root Fracture.

INTRODUCTION: This study evaluated the image quality and the diagnosis of root fractures when using the Zoom Reconstruction tool (J Morita, Kyoto, Japan). METHODS: A utility wax phantom with a metal sample inside was used for objective evaluation, and a mandible with 27 single-rooted teeth (with and without obturation and with and without vertical or horizontal fractures) was used for diagnostic evaluation. The images were acquired in 3 protocols: protocol 1, field of view (FOV) of 4 × 4 cm and a voxel size of 0.08 mm; protocol 2, FOV of 10 × 10 cm and a voxel size of 0.2 mm; and protocol 3, Zoom Reconstruction of images from protocol 2 (FOV of 4 × 4 cm and a voxel size of 0.08 mm). The objective evaluation was achieved by measuring the image noise, and the diagnosis of fractures was performed by 3 evaluators. The area under the receiver operating characteristic curve was used to calculate accuracy, and analysis of variance compared the accuracy and image quality of the protocols. RESULTS: Regarding quality, protocol 1 was superior to protocol 2 (P < .0001) and Zoom Reconstruction (P < .0001). Additionally, images of protocol 2 presented less noise than the Zoom Reconstruction image (P < .0001); however, for diagnosis, Zoom Reconstruction was superior in relation to protocol 2 (P = .011) and did not differ from protocol 1 (P = .228) for the diagnosis of a vertical root fracture in filled teeth. CONCLUSIONS: The Zoom Reconstruction tool allows better accuracy for vertical root fracture detection in filled teeth, making it possible to obtain a higher-resolution image from a lower-resolution examination without having to expose the patient to more radiation.

A bioética no contexto da Odontologia Hospitalar: uma revisão crítica / Bioethics in the context of the Hospital Dentistry: a critical review

Objetivo: realizar uma reflexão sobre a aplicação dos princípios bioéticos na atuação do cirurgião-dentista em âmbito hospitalar. Material e Métodos: uma revisão crítica da literatura foi realizada acessando-se as bases de dados PubMed, Scielo e Biblioteca Virtual em Saúde, utilizando-se os descritores "Bioética", "Equipe Hospitalar de Odontologia", "Ética Odontológica" e "Ética Institucional". Resultados: não foram encontrados estudos específicos sobre o tema proposto. Há escassez de trabalhos na literatura científica específicos sobre a aplicação dos princípios bioéticos ao dia a dia dos profissionais de Odontologia em âmbito hospitalar. Conclusão: a observância e o respeito aos pilares bioéticos da autonomia, justiça, beneficência e não maleficência devem estar incluídos nas atitudes do cirurgião-dentista e da equipe multiprofissional, minimizando os desconfortos ocasionados por problemas de ordem geral e bucal.

Objective: to reflect on the application of the basic principles of bioethics in the performance of the dentist in a hospital environment. Materials and Methods: a critical review of the scientific literature was performed by searching the PubMed, Scielo, and Virtual Health Library databases using the descriptors "Bioethics," "Dental Staff, Hospital," "Ethics, Dental" and "Ethics, Institutional." Results: there were no specific studies on the proposed theme. There was a lack of studies in the scientific literature on the specific application of the bioethical principles in the routine of dental professionals at hospitals. Conclusion: the observance and respect for the bioethical pillars of autonomy, justice, beneficence and non-maleficence must be included in the attitudes of the dentist and the multidisciplinary team, minimizing the discomforts caused by problems of general and oral disorders.

Comparative dimensional tomographic study of the mandibular condyle of individuals with transverse maxillary deficiency

Transverse maxillary deficiency is characterized by posterior uni or bilateral crossbite, crowded and rotated teeth, as well as high palate. Its treatment in adult individuals is surgically assisted rapid palatal expansion. The aim of this study was to verify the occurrence of dimensional alterations in the mandibular condyles of patients with TMD submitted to surgically assisted maxillary expansion. Measurements of the mandibular condyles using the DISTANCE tool in cone beam computed tomography iCat software were performed. The values obtained were submitted to statistical analysis by the paired t-test and the results showed statistically significant dimensional reduction in the axial posterior-anterior lateral (-0.74mm), axial posterior-anterior lateral left (-0.90mm) and coronal medium right (-1.24mm) dimensions. The coronal inferior (1.13mm), coronal inferior left (1.78mm) and coronal superior-inferior right (0.76mm) measurements showed statistically significant dimensional increase. The results allowed us to conclude that dimensional alterations occurred in the mandibular condyles in individuals with maxillary transversal deficiency that underwent surgically assisted rapid palatal expansion (SAPE), which can be understood by remodeling, since they are characterized by dimensional increase or reduction, depending on the location where the measurement was performed (AU)

Study of Genial Tubercles of Craniofacial Anomalies Individuals on Cone Beam Computed Tomography Scans.

PURPOSE: Genial tubercles (GTs) are bony protuberances on the lingual aspect of the mandible symphysis, where genioglossus and geniohyoid muscles are inserted. In the literature, few papers report their real dimensions. Cleft lip and palate are craniofacial anomalies involving the maxilla, but the anatomical structures of the mandible can be altered when these have associated with the cleft, some syndrome. This study aimed to evaluate the GTs of 30 individuals and to make their measurements in cone beam computed tomography examinations. METHODS: A sample of 30 individuals, 19 of them with cleft lip and palate, 6 individuals with Treacher Collins syndrome (TCS), and 5 individuals with Pierre Robin sequence, was used. The GTs were evaluated about the amount and the following measurements were performed: A--distance from the apex of the central incisors to GT, B--mandibular thickness in the region of GT, C-GT height, D-GT width, and E--distance from inferior border of mandible to GT. RESULTS: The individuals presented since the absence of GTs to 3. The TCS group had the highest average of the measurements A, D, and E with statistical difference (P = 0.006) (P = 0.011) and (P = 0.017), respectively. The Pierre Robin sequence group had the highest average measurement of B and C, but there was no statistical difference. CONCLUSIONS: The difference in the measurements can be explained perhaps because individuals with TCS have glossoptosis and changes on retrognathic mandible, which would affect the position of the GT.

Analysis of the reproducibility of the gray values and noise of a direct digital radiography system.

The aim of this study was to evaluate the reproducibility of the gray values and noise of a direct digital radiography system (Visualix eHD) for various exposure times and analyzed regions. To obtain radiographic images in a standardized manner, the digital sensor of the system and a stepwedge were positioned in a phantom at a focus-film distance of 30 cm in a dental device at 70 kV, 7 mA and 2.2 mm filtration. Ten consecutive repetitions of X-ray imaging were performed at each exposure time (0.05, 0.07, 0.09 and 0.13 s). Gray values were analyzed using ImageJ software in five regions of interest (ROIs): alveolar bone (AB), soft tissue (ST) and three steps of the stepwedge (S1, S2 and S3). The results showed that both the variability of the gray values and the noise were statistically greater (p < 0.05) in the most radiolucent region (ST). Only the noise was affected by the exposure time. In conclusion, the reproducibility of the gray values and the noise of the Visualix eHD system can vary in specific areas with different radiolucency.

Identification of the bony canal of the posterior superior alveolar nerve and artery in the maxillary sinus: tomographic, radiographic, and macroscopic analyses.

The aim of this study was to identify the shape and route of the bony canal of the posterior superior alveolar artery (PSAA) and posterior superior alveolar nerve (PSAN) using different identification methods, including computed tomography (CT), panoramic radiograph, and macroscopic evaluation (corpse and dry skull). Twenty-four patients were analyzed by CT and panoramic and posterior anterior (PA) radiographs; additionally, 90 dry skulls and 21 dissected anatomical specimens were examined. Three-dimensional-CT revealed that the lateral wall of the maxillary sinus resembled a tunnel format in 60% of the treated patients. Out of all 24 patients, the panoramic radiograph identified the bony canal in only one patient; whereas the PA radiograph identified it in 80% of the patients. The dry skulls showed tunnellike routes of the PSAA and PSAN in 65% of the cases. Moreover, the pathway was also visibly observed in the dissected anatomical specimens as a straight shape in 85% of the cases. Thus, our results demonstrated that the most common shape of the bony canal of the PSAA and PSAN is the tunnel format with a straight route by 3D-CT, posterior anterior radiography, and macroscopic evaluation. However, in the panoramic radiographs, it was difficult to identify this canal.

Utilização e vantagens da TomografiaComputadorizada por Feixe Cônico emUniversidade Pública / Use and advantages of Cone Beam Computed Tomography in Public University

Realizar uma análise crítica sobre a utilização da Tomografia Computadorizadapor Feixe Cônico (TCFC) na Faculdade de Odontologia de Bauru - USP e as respectivas indicaçõesdeste exame por imagem. Materiais e Métodos: O estudo foi realizado por um únicoexaminador, que avaliou e registrou todos os dados referentes às imagens de TCFC realizadasno período compreendido entre os anos de 2008 a 2011. Resultados: Um total de 1061 examesde imagem de TCFC foram solicitados em um período de quatro anos. Destes, foram considerados722 exames correspondentes ao critério de inclusão. Os motivos pelas quais os examesforam solicitados: avaliação ortodôntica, avaliação endodôntica, reabsorção dentária, cirurgiaparaendodôntica, localização de sialólito, avaliação óssea, dente supranumerário, avaliação daarticulação temporomandibular,, fratura radicular, dente irrompido, avaliação de terceiro molar,retratamento endodôntico, avaliação do seio maxilar, diagnóstico de lesão maxilar, avaliaçãoperiodontal, diagnóstico de lesão mandibular, controle pós-operatório e avaliação para implante.Conclusão: As solicitações de TCFC na Faculdade de Odontologia de Bauru - USP no períododeterminado no estudo em questão foram coerentes com as indicações apresentadas pela literaturacientífica, o preenchimento completo da requisição para a realização do atendimentoainda não é uma prática frequente e mecanismos para o esclarecimento dos usuários do serviço...

Objective: To conduct a critical analysis on the use of Cone-Beam Computed Tomography(CBCT) scanner at Bauru School of Dentistry (USP/Brazil) and the indications of this imagingtechnique. Materials and Methods: The study was conducted by a single examiner, who evaluatedand recorded all data pertaining to the images of CBCT between the year of 2008 and2011. Results: A total of 1061 imaging of CBCT were requested in the four years of the study.Among them, 722 were considered relevant to the inclusion criteria exams. The reasons whythe tests were requested were: orthodontic evaluation, endodontic evaluation, tooth resorption,paraendodontic surgery, salivary calculi location, bone evaluation, supernumerary teeth,temporomandibular joint assessment, root fracture, erupted teeth, third molar evaluation, endodonticretreatment , evaluation of the maxillary sinus, diagnosis of jaw injury, periodontalevaluation, postoperative control and evaluation for implantation. Conclusion: Applications ofCBCT at Bauru School of Dentistry (USP-Brazil) in the given period in the current study wereconsistent with the indications established by the scientific literature. Filling out the applicationto perform the service is still not a common practice and mechanisms for the clarification ofthe service users...

Analysis of the reproducibility of the gray values and noise of a direct digital radiography system

The aim of this study was to evaluate the reproducibility of the gray values and noise of a direct digital radiography system (Visualix eHD) for various exposure times and analyzed regions. To obtain radiographic images in a standardized manner, the digital sensor of the system and a stepwedge were positioned in a phantom at a focus-film distance of 30 cm in a dental device at 70 kV, 7 mA and 2.2 mm filtration. Ten consecutive repetitions of X-ray imaging were performed at each exposure time (0.05, 0.07, 0.09 and 0.13 s). Gray values were analyzed using ImageJ software in five regions of interest (ROIs): alveolar bone (AB), soft tissue (ST) and three steps of the stepwedge (S1, S2 and S3). The results showed that both the variability of the gray values and the noise were statistically greater (p < 0.05) in the most radiolucent region (ST). Only the noise was affected by the exposure time. In conclusion, the reproducibility of the gray values and the noise of the Visualix eHD system can vary in specific areas with different radiolucency.

Pixel value analysis for detection of simulated early external root resorption.

The aim of this study was to determine the efficacy of pixel value analysis using images generated by the Digora™ and Visualix™ systems for the early detection of external root resorption (ERR). Thirty extracted human lower incisors were radiographed using the Digora and Visualix systems; then, ERR was induced by immersing the teeth in 6 mol L-1 of hydrochloric acid for different periods of time (10, 30 and 60 minutes). ERR was confirmed by calcium quantification with an atomic absorption spectrophotometer. One digital image was acquired per time period at 70 kVp, 7 mA, 2.2 mm filtration, focus-film distance of 30 cm, and with exposure times of 0.09 s in the Digora system and 0.05 s in Visualix system. The region of interest was defined using ImageJ software. Statistical analysis was performed using ANOVA and Pearson's correlation (p < 0.05). There was no statistically significant difference between the time for ERR induction and the pixel values with either system. A positive correlation between the time of ERR induction and the calcium concentration was observed (r = 0.8892; p < 0.001). In conclusion, independent of the site of ERR induction and the digital system, pixel value analysis was not effective for ERR detection.

Anatomical variation of the maxillary sinus in cone beam computed tomography.

Purpose. The aim of this paper is to report a case in which the cone beam computed tomography (CBCT) was important for the confirmation of the presence of maxillary sinus septum and, therefore, the absence of a suspected pathologic process. Case Description. A 27-year-old male patient was referred for the assessment of a panoramic radiograph displaying a radiolucent area with radiopaque border located in the apical region of the left upper premolars. The provisional diagnosis was either anatomical variation of the maxillary sinuses or a bony lesion. Conclusion. The CBCT was important for an accurate assessment and further confirmation of the presence of maxillary septum, avoiding unnecessary surgical explorations.