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1.
Clin Oral Investig ; 23(3): 1263-1270, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29984377

RESUMO

OBJECTIVES: To evaluate the influence of artifacts produced by zirconium implant on the diagnosis of vertical root fracture (VRF) in teeth close and distant to the implant in cone beam computed tomography (CBCT) images. We also determined if kilovoltage (kVp) and metal artifact reduction (MAR) tool could influence this diagnosis. MATERIALS AND METHODS: Twenty single-root teeth were divided in control and fractured groups (n = 10). The teeth were randomly positioned in the first and second and right and left pre-molar alveoli of a dry human mandible. CBCT exams were acquired using a ProMax 3D unit with varying kVp (70, 80, or 90 kVp), with or without MAR, and with and without a zirconium implant placed in the alveolus of first right molar. The images were evaluated by five observers. The area under the receiver operating characteristic curve (ROC), sensitivity, and specificity were calculated and compared by analysis of variance with a significance level of 5%. RESULTS: In general, ROC and sensitivity were not affected by the factors studied (p > 0.05). The main effects occurred in specificity; when implant was used without MAR, the values were lower for tooth 45 for all kVps (p = 0.0001). CONCLUSIONS: Artifacts produced in the vicinity of teeth with suspected VRF impair the diagnosis by decreasing the specificity, because they can mimic the VRF line generating false positives. However, MAR improves the specificity, being its use recommended when metallic objects are present near teeth with suspected VRF. CLINICAL RELEVANCE: Since nowadays, many patients who undergo CBCT show implants and they definitively produce artifacts, it is important to evaluate the influence of such artifacts in the diagnosis of teeth that are close to the generator-artifact object.


Assuntos
Artefatos , Implantes Dentários , Fraturas dos Dentes/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Humanos , Mandíbula , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/lesões
2.
Acta Odontol Scand ; 75(2): 79-86, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27881042

RESUMO

OBJECTIVE: To assess the correlation between third molar mineralization (TMM), spheno-occipital synchondrosis (SOS) fusion, chronologic age and cervical vertebrae maturation (CVM) for skeletal maturation. MATERIALS AND METHODS: Radiographs for 116 patients between 8 and 28 years were evaluated for age determination using mandibular TMM, SOS fusion and CVM. Spearman Correlation and Kappa test analyses were used to assess the relationship between variables and for intraobserver reliability. RESULTS: Strong correlation was found between chronological age and TMM for males (r = .802) and females (r = .842), very strong correlation was found between age and CVM for males (r = .812) and moderate for females (r = .449), it was strong between age and SOS fusion for males (r = .810) and females (r = .643). Correlation between TMM and SOS was found to be strong for males (r = .759) and moderate for females (r = .534), it was strong between TMM and CVM for males (r = .723) and weak for females (r = .371). Very strong correlation was found between CVM and SOS fusion for males (r = .851) and strong correlation for females (r = .618). CONCLUSION: Good correlation was found between the degrees of TMM, fusion of SOS and CVM in young Turkish population.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Determinação da Idade pelos Dentes/métodos , Vértebras Cervicais/diagnóstico por imagem , Dente Serotino/diagnóstico por imagem , Osso Occipital/diagnóstico por imagem , Osso Esfenoide/diagnóstico por imagem , Adolescente , Vértebras Cervicais/crescimento & desenvolvimento , Criança , Feminino , Humanos , Masculino , Dente Serotino/crescimento & desenvolvimento , Radiografia Panorâmica , Reprodutibilidade dos Testes , Calcificação de Dente , Turquia , Adulto Jovem
3.
Int J Legal Med ; 130(3): 799-808, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26637329

RESUMO

For forensic age estimation, radiographic assessment of third molar mineralization is important between 14 and 21 years which coincides with the legal age in most countries. The spheno-occipital synchondrosis (SOS) is an important growth site during development, and its use for age estimation is beneficial when combined with other markers. In this study, we aimed to develop a regression model to estimate and narrow the age range based on the radiologic assessment of third molar and SOS in a Turkish subpopulation. Panoramic radiographs and cone beam CT scans of 349 subjects (182 males, 167 females) with age between 8 and 25 were evaluated. Four-stage system was used to evaluate the fusion degree of SOS, and Demirjian's eight stages of development for calcification for third molars. The Pearson correlation indicated a strong positive relationship between age and third molar calcification for both sexes (r = 0.850 for females, r = 0.839 for males, P < 0.001) and also between age and SOS fusion for females (r = 0.814), but a moderate relationship was found for males (r = 0.599), P < 0.001). Based on the results obtained, an age determination formula using these scores was established.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Determinação da Idade pelos Dentes/métodos , Dente Serotino/diagnóstico por imagem , Osso Occipital/diagnóstico por imagem , Osteogênese , Osso Esfenoide/diagnóstico por imagem , Adolescente , Adulto , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Antropologia Forense , Odontologia Legal , Humanos , Masculino , Dente Serotino/crescimento & desenvolvimento , Radiografia Panorâmica , Análise de Regressão , Estudos Retrospectivos , Caracteres Sexuais , Calcificação de Dente , Adulto Jovem
4.
Clin Oral Implants Res ; 27(9): 1072-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26364803

RESUMO

BACKGROUND: Buccal plate thickness is of clinical importance in treatment planning for implants. The purpose of this study was to evaluate the buccal plate thickness in posterior dentate areas of both the maxilla and mandible using cone beam computed tomography in order to estimate the approximate distributions of this anatomic variable. METHODS: Two hundred and sixty-five subjects were included for a total of nine hundred and thirty-four roots assessed by cone beam computed tomography. CBCT scans were taken and evaluated at the ideal buccolingual cross-sections of each root at 1 mm, 3 mm, and 5 mm apical to the alveolar crest to measure buccal plate thickness. Data are reported by geometric means and 95% confidence intervals. RESULTS: Both arches demonstrated increasing buccal plate thickness from anterior to posterior. Maxillary teeth had a significant decrease in thickness from coronal to apical along the tooth root (P < 0.001), except at second molars. The first premolar and mesial root of the first molar were significantly thinner than all other roots in the maxilla. Conversely, the mandible demonstrated a significant increase in buccal plate thickness from coronal to apical (P < 0.001). The premolars were significantly thinner than all other roots. Age and sex were found to have limited impact on buccal plate thickness in both arches. CONCLUSIONS: Buccal plate thickness is highly dependent upon the arch position, tooth location, and measurement point, but age and sex have limited impact.


Assuntos
Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Raiz Dentária/diagnóstico por imagem , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Pessoa de Meia-Idade , Dente Molar/diagnóstico por imagem , Fatores Sexuais , Adulto Jovem
5.
Gen Dent ; 63(4): 56-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26147169

RESUMO

With the increasing use of digital radiography, the display parameters of the devices used to view radiographs have become important factors in caries detection. Interest in the use of tablet devices for this application has increased due to their availability, portability, and ease of use. However, to be effective in clinical situations, these portable devices must have displays that perform well under multiple lighting conditions and at different angles. The purpose of this study was to assess the utility of the iPad with Retina Display for the detection of Class II caries under common overhead lighting conditions. The device was used in both standing and angled positions by 5 reviewers, and their diagnoses of caries were compared to the diagnoses the same reviewers made using a thin-film transistor flat-panel display (TFT-FPD) in dim lighting conditions. Histological analysis was used as the gold standard to confirm the presence or absence of caries. In a standing position, the tablet device performed as well as the TFT-FPD. When used in the angled position, the tablet performed slightly worse than the TFT-FPD. The findings suggest that if the user can compensate for overhead glare, the tablet device may perform as well as a calibrated, upright display in a dimly lit room.


Assuntos
Computadores de Mão , Cárie Dentária/diagnóstico , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/patologia , Humanos , Radiografia Dentária , Sensibilidade e Especificidade
6.
Tex Dent J ; 132(5): 310-4, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26234012

RESUMO

A distinctive form of paradental cyst can occur on the buccal and apical aspects of erupted mandibular molars. This cyst has peculiar clinical and radiographic features, although the microscopic findings are the same as those of odontogenic inflammatory cysts. Diagnostic and therapeutic problems can occur when this lesion is misinterpreted as a radicular cyst. The purpose of this paper is to present two additional cases of a paradental cyst in the buccal and mesial aspects of a mandibular first molar involving the apical area. The difficulty of diagnosis, treatment, and controversies regarding terminology are also discussed.


Assuntos
Doenças Mandibulares/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Cisto Periodontal/diagnóstico por imagem , Criança , Tomografia Computadorizada de Feixe Cônico/métodos , Cisto Dentígero/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Cistos Odontogênicos/diagnóstico , Cisto Radicular/diagnóstico , Radiografia Interproximal , Radiografia Panorâmica
7.
Dent Traumatol ; 29(6): 445-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23566073

RESUMO

Digital intraoral radiographic systems have been rapidly replacing conventional dental X-ray films for diagnosis of dental diseases. Current scientific literature supports the use of these digital systems for the detection of dental caries, periodontal bone loss, and periapical pathologies. However, relatively few studies have been published addressing the detection of dental root fractures. The purpose of this study was to compare the intraoral F-speed film (Insight) with two photostimulable phosphor (PSP) indirect digital systems (ScanX and Digora Optime) for the detection of simulated dental root fractures. Ten raters evaluated images acquired from 10 dry human cadaver mandibles under optimal viewing conditions. These data were analyzed by a 5-point receiver operating characteristic curve analysis for statistical differences. Sensitivity and specificity of these systems were also assessed. Since statistically significant difference between the systems was not observed, the results of this study agreeably support indirect digital PSP plates as an alternative to the evaluated conventional film for the detection of dental root fractures.


Assuntos
Radiografia Dentária Digital/estatística & dados numéricos , Radiografia Dentária/métodos , Fraturas dos Dentes/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem , Humanos , Radiografia Dentária Digital/métodos , Sensibilidade e Especificidade , Filme para Raios X
8.
Dent Traumatol ; 28(3): 233-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22066949

RESUMO

The ability of a periapical radiograph to exhibit the fracture depends on many factors including, but not limited to, the resolution of the image. The quality can be reduced by the image compression. The purpose of this study is to evaluate the effect of Joint Photographic Experts Group (JPEG) compressions on the diagnostic capability of periapical images in the detection of root fractures. Ten dry human mandibles containing 151 teeth were used in this study. Mandibles were radiographed with direct digital imaging sensor using the paralleling technique. Four observers detected root fracture on the images saved in one uncompressed and two compressed formats. Receiver operating characteristic (ROC) and anova analyses were performed to compare the performance of the three different systems and evaluate the effect of the compression on the accuracy of root fracture detection. Results did not show any statistically significant difference between the original, large images presented in tagged image file format (TIFF) and the two compressed images (JPEG medium file and JPEG small file images) in the detection of root fractures. The intra-rater comparison showed a significant consistency in the detection of the fracture. The compression reduced the file size considerably (from 1.77 MB to 453 and 95 Kb), but it did not affect the accuracy of root fracture detection. The file size reduction, on the other hand, is very beneficial for image electronic storage and mainly in teleradiology.


Assuntos
Compressão de Dados/métodos , Radiografia Dentária Digital/métodos , Fraturas dos Dentes/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem , Análise de Variância , Humanos , Curva ROC , Sensibilidade e Especificidade
9.
Oral Radiol ; 38(3): 370-377, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34609699

RESUMO

OBJECTIVES: Enamel pearl (EP) is an ectopic growth of enamel that is generally round and white and it firmly adheres to the external root surface of tooth. The aim of this study was to assess the prevalence and imaging features of enamel pearls (EPs) and to investigate the potential relationship between EP and supernumerary tooth. METHODS: Cone beam computed tomography (CBCT) images of 1003 patients were evaluated for the presence of EP. Descriptive characteristics of gender and age of patients and imaging features of EPs and presence of supernumerary tooth were recorded. RESULTS: In this study, 72 EPs were radiographically detected in 63 molars in 43 patients, with a person prevalence of 4.29% and tooth prevalence of 0.71%. Most of the EPs (95.83%) were detected in maxillary molars especially in third (n = 42, 58.33%) and second molars (n = 18, 25%). They were more frequently located at mesial (n: = 21; 29.16%); distal (n = 16; 22.22%) proximal surface of roots and the furcation between the disto-buccal and the palatal roots (n = 12; 16.67%) respectively. CBCT images of 109 (10.87%) patients showed supernumerary tooth/teeth and 13 of these also presented EP. A statistical significant relationship between supernumerary tooth and EP was found (p = 0.001). Additionally, CBCT images of four EPs showed corticated hypodens tracts similar to gubernaculum dentis (GD). CONCLUSIONS: Clinicians and radiologists should be aware that EPs are most frequently observed in maxilla especially in third and second molars. Presence of supernumerary tooth might be associated with higher presence of EPs.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Dente Supranumerário , Esmalte Dentário/diagnóstico por imagem , Humanos , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem , Dente Supranumerário/diagnóstico por imagem
10.
Gen Dent ; 59(2): e72-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21903512

RESUMO

This study sought to identify and follow the course of the incisive canal in the mental interforaminal region of the human mandible and to describe other anatomical landmarks present in this region. Cone beam computerized tomography (CBCT) studies for 40 patients were collected from the database at the Department of Oral & Maxillofacial Radiology, School of Dentistry, Lebanese University. Ten patients had edentulous mandibles; the other 30 had partially or completely dentate mandibles. Axial native images and panoramic and cross-sectional reconstructions were examined to assess the anatomical landmarks in the anterior mandible. Multiple neurovascular canals and foramina were clearly detected on CBCT studies of the mandible. Numerous foramina were seen on the internal surface of the mandible, even distant from the midline. The incisive canal was identified in 97.5% of the images. These anatomical landmarks should be evaluated carefully during preoperative planning.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Mandíbula/diagnóstico por imagem , Adulto , Pontos de Referência Anatômicos/anatomia & histologia , Pontos de Referência Anatômicos/diagnóstico por imagem , Anatomia Transversal/métodos , Dentição , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Arcada Edêntula/diagnóstico por imagem , Arcada Edêntula/patologia , Arcada Parcialmente Edêntula/diagnóstico por imagem , Arcada Parcialmente Edêntula/patologia , Masculino , Mandíbula/irrigação sanguínea , Mandíbula/inervação , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Radiografia Panorâmica/métodos , Estudos Retrospectivos , Adulto Jovem
11.
Scanning ; 2021: 2679012, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484553

RESUMO

This study was aimed to evaluate the diagnostic accuracy of cone beam computed tomography (CBCT) in detecting noncavitated approximal caries at different exposure parameters and to assess the impact of artifacts generated by amalgam restorations in an in vitro study. Seventy-eight approximal surfaces of extracted teeth were prepared with intentionally created noncavitated approximal caries of different depths; then, thirteen teeth with class 2 amalgam restorations were replaced with one tooth with normal surfaces in each block. CBCT volumes for all teeth were acquired using a Planmeca Promax 3D Mid imaging unit before and after placement of amalgam teeth, with different exposure parameters at low and high definition, both applying and omitting the Metal Artifact Reduction algorithm. The lesions were classified into four groups with regard to lesion extension. All teeth underwent histological analysis as gold standard. The histological examination showed that the distribution of lesions was as follows: 39.8% sound, enamel lesions of less and more than half the enamel thickness each 17.8%, and 24.6% dentin lesions. The detection sensitivity was found to be 0.972%, and specificity was found to be 0.937% for the detection of noncavitated approximal initial enamel and dentin caries. The highest diagnostic accuracy was found when using operating parameters of 90 kVp, 8 mA, and high resolution (75 µm) with nonamalgam teeth; all modes showed statistically significant higher AUCs than mode 2 (80 kVp, 7 mA, and 75 µm). However, for teeth with amalgam restorations, the highest accuracy was obtained at low resolution (200 µm) with the other parameters kept the same. It could be concluded that increasing the peak voltage and current improves diagnostic accuracy for the detection of noncavitated approximal caries. Moreover, diagnostic accuracy was found to be higher upon using high spatial resolution when diagnosing caries without adjacent amalgam restorations. There is a statistically significant difference with and without amalgam with respect to all modes.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Artefatos , Tomografia Computadorizada de Feixe Cônico , Cárie Dentária/diagnóstico por imagem , Humanos , Sensibilidade e Especificidade
12.
J Periodontol ; 92(3): 419-427, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32786147

RESUMO

BACKGROUND: The aim of this study was to determine if image enhancement improves a clinician's ability to identify the presence of calculus on digital radiographs. METHODS: Seventy-one hopeless teeth were collected from 34 patients. Teeth were stained with 1% methylene blue, the largest interproximal calculus deposit was scored, and photographs of each interproximal root surface were taken. The surface area of calculus deposit was determined as a percentage of the total interproximal root surface area. Digital radiographs of teeth taken before extraction were modified using the following enhancements: auto-contrast, emboss, invert, and sharpen. Radiographic presence of calculus was determined by two examiners. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each examiner and enhancement. A receiver operating characteristic curve was used to compare differences between the image enhancements in the detection of dental calculus. The kappa statistic was used to compare ratings between examiners. RESULTS: None of the enhanced images were statistically superior to original images in identifying radiographic calculus (P > 0.05). The average sensitivity of digital radiography was 50%, average specificity was 82.2%, PPV was 94%, and NPV 23.2%. A threshold of >30% of interproximal root surface covered with calculus and increasing size of deposits were associated with improved detection (P < 0.05). CONCLUSIONS: Digital enhancements do not significantly improve radiographic detection of dental calculus. As area of calculus on the root surface and size of calculus deposits increased, sensitivity of detection also increased.


Assuntos
Intensificação de Imagem Radiográfica , Dente , Cálculos Dentários/diagnóstico por imagem , Humanos , Radiografia Dentária Digital , Raiz Dentária
13.
Clin Exp Dent Res ; 7(6): 1103-1111, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34096195

RESUMO

OBJECTIVES: To examine ridge dimensional changes and histologic parameters of healing when ridge preservation (RP) was performed at molar sites using dense polytetrafluoroethylene (dPTFE) membrane alone, without a bone graft. MATERIAL AND METHODS: Eighteen patients had molar extraction and RP using dPTFE membrane alone. Ridge dimensions were measured using two standardized cone beam computerized tomography (CBCT) scans taken within 72 h and 3 months following extraction. Following a 3-month healing period, an implant osteotomy was prepared using a trephine drill and bone cores were collected for histological analysis. Four-arm analyses were performed using data from three previously published study arms of the same research group. RESULTS: There was a significant change in the buccal ridge height between the four groups at all aspects of the socket. Alveolar ridge width reduction at 3 mm from crest for all aspects (mesial, midpoint, distal) of the socket showed statistically significant difference for dPTFE alone group compared to the other three groups. Percentage of vital bone formation (62.10%) was significantly greater in dPTFE alone group compared to the other groups. CONCLUSIONS: RP using dPTFE membrane alone in molar sites with intact socket walls showed successful outcomes in maintaining ridge dimensions and in histologic wound healing.


Assuntos
Politetrafluoretileno , Alvéolo Dental , Colágeno , Humanos , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Estudos Prospectivos , Extração Dentária/efeitos adversos , Alvéolo Dental/diagnóstico por imagem , Alvéolo Dental/cirurgia , Cicatrização
14.
Int J Oral Maxillofac Implants ; 25(3): 548-57, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20556254

RESUMO

PURPOSE: The purpose of this study was to evaluate the radiographic bone level and stability changes around early loaded chemically modified sandblasted and acid-etched implants with and without a machined collar. MATERIALS AND METHODS: Seventy-two chemically modified sandblasted and acid-etched implants 4.1 mm in diameter and 8 mm in length were placed in six dogs. Thirty-six implants had no machined collar (NMC) and 36 had a 2.8-mm machined collar (MC). Resonance frequency measurements were obtained at placement and weekly for 3 weeks. All implants were loaded 21 days after surgery. Standardized periapical radiographs were obtained at baseline, at 3 weeks, and at 3, 6, 9, and 12 months. The radiographs were randomized and digitized, and linear measurements of the distance from the first bone-to-implant contact to the shoulder of the implant were performed at the mesial and distal aspects of each implant. For statistical analysis, mixed-model repeated-measures analysis of variance was used. RESULTS: All implants achieved hard and soft tissue integration clinically and radiographically and were clinically immobile. From placement to week 3, the mean implant stability increased for MC implants by more than 5 ISQs and for NMC implants by more than 7 ISQs. Radiographically, there were significant differences between treatment groups beginning at 3 months. After 12 months of loading, the MC implants presented a mean bone loss of 1.00 mm and the NMC implants presented a mean bone gain of 0.11 mm. CONCLUSIONS: Chemically modified sandblasted and acid-etched implants without a machined collar presented bone gain, and implants with a machined collar showed bone loss after a 1 year following early (21-day) loading. The tendency toward a coronal apposition of bone observed under these conditions may be attributed to the osteoconductive properties of the chemically modified surfaces of these implants and to the absence of the machined collar.


Assuntos
Perda do Osso Alveolar , Corrosão Dentária/métodos , Implantes Dentários/efeitos adversos , Planejamento de Prótese Dentária/efeitos adversos , Osseointegração , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Animais , Implantação Dentária Endóssea , Retenção em Prótese Dentária , Cães , Masculino , Mandíbula , Radiografia , Distribuição Aleatória , Propriedades de Superfície , Vibração
15.
J Endod ; 46(8): 1052-1058, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32437787

RESUMO

INTRODUCTION: External cervical resorption (ECR) is a relatively uncommon type of external resorption; its treatment planning and prognosis are largely dependent on the clinician's subjective assessment. This study aimed to provide a volumetric assessment of ECR cases while correlating them to the Heithersay classification, treatment decision, and prognosis determined by 3 calibrated, independent evaluators. METHODS: A total of 168 ECR cases with corresponding periapical radiographs and cone-beam computed tomographic (CBCT) imaging were included in this study. An oral and maxillofacial radiologist calculated the volume occupied by the resorptive defects in root structures on CBCT imaging using Amira software (Thermo Scientific, Waltham, MA). Also, 3 board-certified endodontists evaluated anonymized and randomized periapical radiographs and corresponding CBCT images in separate sessions. Examiners were asked to provide a Heithersay classification, whether they would surgically repair the ECR lesion, and the expected prognosis of each case. RESULTS: The percentage of radicular volume affected by ECR ranged from 0.5%-58% with a median of 12%. The volumetric quantification of ECR best correlated with classification and prognosis assigned by the independent examiners using CBCT evaluation. The greatest variation in agreement was observed on whether to surgically repair the ECR. However, examiners agreed more uniformly on not to treat when the resorptive port of entry was found on either the lingual or proximal surfaces of the tooth. CONCLUSIONS: For the first time, the volumetric quantification of resorptive defects was calculated in vivo and correlated to the Heithersay classification and prognosis. Because the longevity of teeth affected with ECR depends on the integrity of the remaining root, the findings of this study provide important information to help clinicians decide on treatment planning and inform their patients of the expected prognosis. Future studies should focus on automating volumetric assessments of ECR to aid in unbiased chairside treatment planning decisions.


Assuntos
Planejamento de Assistência ao Paciente , Tomografia Computadorizada de Feixe Cônico , Humanos , Prognóstico , Reabsorção da Raiz , Colo do Dente
16.
Artigo em Inglês | MEDLINE | ID: mdl-31956069

RESUMO

OBJECTIVES: The aim of this ex vivo study was to measure the sensitivity, specificity, and receiver operating characteristic (ROC) area under the curve (AUC) of a caries diagnostic system based on photothermal radiometry and modulated luminescence (PTR/LUM) and compare them with the values for digital intraoral radiography (IR) and cone beam computed tomography (CBCT) in detecting recurrent decay. STUDY DESIGN: Class 2 composite restorations were prepared on 70 proximal surfaces: 35 with caries and 35 without caries. The gingival floor of the restored surfaces was assessed for caries under the restorations using each of the 3 modalities. Statistical calculations and analysis were performed using the R statistical computing environment. RESULTS: The average scores for sensitivity among the 6 observers were 0.89 for PTR/LUM, 0.38 for IR, and 0.40 for CBCT. Sensitivity for PTR/LUM was significantly greater than sensitivity for IR and CBCT. Average scores for specificity were 0.83, 0.80, and 0.70 for PTR/LUM, IR, and CBCT, respectively. CBCT had significantly lower specificity. The AUC was 0.65 for IR and 0.59 for CBCT, which were significantly different. PTR/LUM had moderate intraobserver agreement. CONCLUSIONS: PTR/LUM, which involves non-ionizing radiation, can serve as a sensitive adjunct in early caries detection and monitoring.


Assuntos
Cárie Dentária , Luminescência , Tomografia Computadorizada de Feixe Cônico , Humanos , Curva ROC , Radiografia Dentária Digital , Radiometria , Sensibilidade e Especificidade
17.
Artigo em Inglês | MEDLINE | ID: mdl-31628073

RESUMO

OBJECTIVE: We quantitatively compared the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in T1 weighted imaging (WI) and T2 WI sequences in 3 Tesla (T) magnetic resonance imaging (MRI) using zirconium, titanium (grades 4 and 5), and titanium-zirconium alloy implants to evaluate the effect of implant type and imaging sequence. STUDY DESIGN: MRI was acquired using a 3 T magnet with a 16-channel head coil. Implants of each type were mounted in gel and scanned in axial, coronal, and sagittal planes using fast spin echo sequences in T1 WI (TR = 600, TE = 12 milliseconds) and T2 WI (TR = 3000, TE = 80 milliseconds) sequences. Data were transferred to Synapse 3-D software, and images were measured twice by an oral and maxillofacial radiologist blinded to the type of implants. RESULTS: Zirconium implants resulted in the lowest SNR and CNR values (P < .05). No significant differences were identified between titanium (grades 4 and 5) and titanium-zirconium implants. The T2 WI sequence had a significantly higher SNR and CNR than T1 WI. There was no difference in intraobserver agreement between T1 WI and T2 WI. CONCLUSIONS: CNR and SNR at 3 T MRI are dependent on implant type and imaging sequence. Titanium (grades 4 and 5) and titanium-zirconium implants and the T2 WI sequence produced higher SNR and CNR values.


Assuntos
Implantes Dentários , Titânio , Ligas , Imageamento por Ressonância Magnética , Razão Sinal-Ruído , Zircônio
18.
Dent Traumatol ; 25(4): 358-66, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19515071

RESUMO

Imaging plays an essential role in the evaluation of maxillofacial fractures both pre- and postoperatively. Several studies support the use of conventional two-dimensional imaging for traumas involving mainly the mandible, but for more complex situations advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging have higher indication. Nowadays, besides CT, cone-beam computed tomography (CBCT) has appeared as a reasonable and reliable alternative considering radiation dosage, image quality and comfort for the patient. The purpose of this study was to review the fracture patterns involving the maxillofacial complex, provide a technical and practical comparison between CT and CBCT, and finally present the potential applications of CBCT illustrated with clinical examples.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Traumatismos Maxilofaciais/diagnóstico por imagem , Fraturas Cranianas/diagnóstico por imagem , Ossos Faciais/lesões , Humanos , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X
19.
Acta Inform Med ; 27(3): 167-170, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31762572

RESUMO

INTRODUCTION: Fractal dimension (FD) on periapical radiographs is used as a simple descriptor of the complex architecture of the trabecular bone surrounding the dentition. It is used on periapical and panoramic radiographs as a descriptor of the complex architecture of trabecular bone surrounding teeth. AIM: The aim of this study was to evaluate the effect of image resolution and different compression levels on fractal dimension of alveolar bone with images obtained using storage phosphor plate (SPP) system. METHODS: Periapical images of premolar and molar teeth on both sides of three dry human mandibles were obtained with Digora Optime (Soredex Corp., Helsinki, Finland) SPP system. The SPPs were exposed equally and scanned immediately after exposure with standard, high and very high resolutions. All the images then were compressed and saved by degrees of 0%, 25%, 50%, 75% and 90%. FD was calculated using public domain software (ImageJ with FracLac plug-in) on two non-overlapping regions of interest (ROIs) on premolar and molar periapical bone areas of each radiograph using differential box-counting method. The ROIs on corresponding images were of the same size and position. FDs were compared using two-way ANOVA and Tukey-Kramer multiple comparison tests (p=0.05). RESULTS: There was no significant difference in FD calculations in different levels of compression for all the resolutions. Images obtained with high resolution scans showed significantly lower variation in FD values compared to very high and standard resolutions for all compressions (p<0.0001). CONCLUSION: The high resolution demonstrated the lowest variation in FD values in all levels of compression which makes it the most reliable and consistent resolution for measuring the FD values. The level of compression does not make a significant difference in FD values for all the scan resolutions. Scanning resolution of SPPs should be carefully chosen when evaluating the change in FD of alveolar bone for various bone disorders.

20.
Dentomaxillofac Radiol ; 48(8): 20190139, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31386553

RESUMO

OBJECTIVES: To assess the contrast-to-noise ratio (CNR) of four different types of dental implant materials in CT and cone beam CT (CBCT) images with varying scan settings. METHODS: Four different types of implants: zirconium (Zr), titanium (Ti) Grade 4 and 5 and titanium-zirconium (Ti-ZrO2) alloy were placed in a 3% gelatin phantom in a cylindrical plastic container and scanned with two different CT machines (GE Medical systems and Toshiba Medical Systems) and one CBCT machine (I-CAT, Imaging Sciences International) with different voxel sizes of 0.2, 0.25, 0.3 and 0.4 mm. Images were analyzed using ImageJ software with the purpose of estimating the CNR. RESULTS: The CNR obtained from images acquired with CT was lower than the CBCT with all voxel sizes tested. 0.3 and 0.4 mm voxel sizes exhibited the highest CNR (p < 0.05) that gives the best image quality. Among the implant materials tested, titanium Grade 5 has the highest levels of CNR while Zirconium has the lowest (p < 0.05). CONCLUSIONS: The optimum protocol for radiographic follow-up in areas near implants on the I-CAT is low-resolution settings (0.3 and 0.4 mm voxel sizes) which gave the highest CNR thus image quality. In presence of Zr implants, an alternative imaging modality (i.e., MRI) may be considered to avoid low-quality images.


Assuntos
Implantes Dentários , Tomografia Computadorizada de Feixe Cônico Espiral , Zircônio , Tomografia Computadorizada de Feixe Cônico , Humanos , Imagens de Fantasmas
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