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1.
J Dent (Shiraz) ; 24(4): 395-403, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38149228

RESUMO

Statement of the Problem: Early detection of caries and the extent of carious lesions for appropriate treatment planning are very important and lead to introduction of new diagnostic tools. Purpose: This study aimed to compare the diagnostic accuracy of VistaCam IX Proxi and bitewing radiography for detection of posterior interproximal caries. Materials and Method: This in vitro study was performed on 40 extracted posterior teeth without cavitated carious lesions. Bitewing radiographs were obtained, infrared (IR) examination was performed, and the teeth were sectioned for histopathological analysis under a stereomicroscope as the gold standard for detection of caries and determination of the extent of carious lesions. Data were analyzed with Cohen's kappa statistic, and Wilcoxon rank sum test. Results: The specificity of VistaCam IX Proxi and bitewing radiography was 71.4% and 87.7%, respectively. Their sensitivity was 100% and 40% for enamel caries, 72.8% and 54.5% for external half dentin caries, and 82.3% and 58.8% for internal half dentin caries, respectively (p= 0.048). Conclusion: Bitewing radiography had a higher specificity and lower rate of false positive results. However, VistaCam IX Proxi had higher sensitivity for caries detection with lower rate of false negative results. Considering the higher sensitivity and significantly lower frequency of false negative results by VistaCam IX Proxi, it may be reliably used for caries detection specially enamel caries, and can serve as an adjunct to bitewing radiography.

2.
Radiol Res Pract ; 2023: 5539719, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554657

RESUMO

Objective: Dental implant artifacts can compromise the quality of cone-beam computed tomography (CBCT) scans and challenge radiographic detection in surrounding regions. This literature review was conducted to examine the impact of implant angle modification on reducing metal artifacts in CBCT scans. Materials and Methods: A scoping review of literature was carried out in PubMed, Embase, Scopus, and Cochrane databases. Results: Different spatial planes, including alpha, beta, gamma, and phi, along with 0°, 5.2°, 9.8°, 14.5°, 15°, 30°, 45°, 60°, 75°, and 90° angles were studied. Changes in the angular position of implants may reduce metal artifacts and improve the quality of CBCT scans. Conclusions: Rotating implants within the alpha plane and angling them at 90° in the alpha plane enables reducing dental implant artifacts.

3.
Int J Dent ; 2022: 8257256, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35662891

RESUMO

Methods and Materials: Cone beam computed tomography records of 35 patients (70 quadrants) from maxilla were evaluated. The images were analyzed using the NNT viewer software (version 23). The measurements were made on axial sections at 2, 4, 6, and 8 mm from CEJ. The optimal sites were defined in terms of mesiodistal palatal or buccal interradicular distance, alveolar cortical bone thickness, and palatal or buccal safe depth of the bone for miniscrew insertion. Descriptive statistics, paired t-test, and repeated measure ANOVA were used to analyze the data. Results: The mean buccal interradicular distance was the lowest between first and second molar (2.44 mm) and the highest between first and second premolar (3.28 mm). The mean palatal interradicular distance was the lowest between first and second premolar (3.64 mm) and the highest between second premolar and first molar (5.30 mm). The mean buccal safe depth was the lowest between canine and first premolar (1.96 mm) and the highest between first and second molar (2.61 mm). The mean palatal safe depth was the lowest between second premolar and first molar (3.35 mm) and the highest between first and second molar (3.56 mm). The thinnest and thickest buccal cortical thicknesses were detected on canine and first molar (1.04 mm) and on the second premolar and second molar (1.56 mm). Conclusion: The quantity and quality of the maxillary alveolar process is an important factor to decide where to insert the orthodontic miniscrews, necessitating careful preoperative evaluation.

4.
J Long Term Eff Med Implants ; 32(2): 61-71, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35695628

RESUMO

The aim of this study was to assess the morphology and dimension of maxillary alveolar ridge at anterior and posterior regions using cone beam computed tomography (CBCT) prior to the placement of immediate implants. CBCT scans of 192 patients were evaluated. Measurements were taken at the cross sectional views in the maxillary central incisor, lateral incisor, canine incisor, first and second premolars and first and second molars regions. Alveolar ridge width and height, buccal plate thickness, buccal undercut, inter-root septum height, and root penetration to sinus floor were measured. Independent T-test was used for statistical analysis. The mean value of alveolar height in the maxillary incisors were higher than the posterior teeth with central incisors having the highest value of 19.23 ± 8.74 mm. At anterior maxilla, the lateral incisor with the mean value of 1.07 ± 0.64 mm exhibits the highest buccal undercut and the thinnest ridge width. At the site of posterior regions premolars had higher buccal undercut than molars. Canine with the mean value of 0.19 ± 0.31 mm thickness at the mid-alveolar of buccal plate, had the thinnest plate among other maxillary incisors. Sinus penetration and inter-root septum height were higher in premolar teeth than molars. The mean value of ridge width at all levels was significantly different between men and women, except at the level of crest in central incisor. CBCT evaluation presents accurate measurements for ridge assessment prior to immediate implant insertion. The recommended appropriate size of implant platform would be 5 mm in the incisor and almost 6 mm in premolar region.


Assuntos
Levantamento do Assoalho do Seio Maxilar , Tomografia Computadorizada de Feixe Cônico Espiral , Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Estudos Transversais , Feminino , Humanos , Maxila/diagnóstico por imagem
5.
J Long Term Eff Med Implants ; 32(2): 73-80, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35695629

RESUMO

Detection of location of greater palatine foramen (GPF) and its anatomical variations are vital prior to posterior maxillary surgeries. The aim of this study is to determine the anatomical position and size of the greater palatine canal and GPF using cone beam computed tomography (CBCT) scan. To determine the anatomical foramen position, the posterior maxilla area was divided into five regions on the axial view (A to E from the mesial surface of the second molar to distal surface of third molar). The length of the canal was investigated on both coronal and sagittal views. Independent t-test was used to analyze the data. Among 80 females and 68 males, the anatomical position of the GPF was mainly located in region E on the left (55%) and the right (50%), and then, respectively, in region D and region C. The mean diameter of GPF was 4/48 mm on the left and 4/63 mm on the right side (P = 0/01). The average length of the canal on the coronal view was 29.46 mm on the left side and 29.75 mm on the right (P = 0.005). The average length of the canal on the sagittal view was 29.62 mm on the left and 30.02 mm on the right (P = 0.001). The anatomical position of the GPF was primarily located distal to the third maxillary molar. CBCT is a valuable diagnostic tool for evaluation of vital anatomic landmarks in the maxillofacial region prior to surgeries.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Palato Duro , Feminino , Humanos , Irã (Geográfico) , Masculino , Maxila/diagnóstico por imagem , Dente Molar
6.
Iran J Radiol ; 13(4): e37265, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27895878

RESUMO

BACKGROUND: Detection of foreign bodies (FBs) is challenging. Selection of a fast and affordable imaging modality to locate the FB with minimal patient radiation dose is imperative. OBJECTIVES: This study sought to compare four commonly used imaging modalities namely cone beam computed tomography (CBCT), magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound (US) for detection of FBs in the head and neck region. MATERIALS AND METHODS: In this in vitro study, iron, glass, stone, wood, asphalt, and tooth samples measuring 0.1 × 0.5 × 0.5 cm were placed in the tongue muscle, soft tissue-bone interface and nasal cavity in a fresh sheep's head and subjected to MRI, US, CT and CBCT. A total of 20 images were captured by each imaging system from the six materials in the afore-mentioned locations. The images were observed by an expert oral and maxillofacial radiologist and a general radiologist. To assess reliability, 20 images were randomly observed by the observers in two separate sessions. The images were classified into three groups of good visibility, bad visibility and invisible. The data were analyzed using SPSS version 18, Wilcoxon Signed Rank, Pearson chi square, and Fisher's exact tests. RESULTS: All FBs in the tongue and at the soft tissue-bone interface had good visibility on US (P = 1.00). Also, CBCT and CT had significantly different performance regarding FB detection (P < 0.001). All wooden samples in the nasal cavity were invisible on CT scans; while, only 20% of them were invisible on CBCT scans. MRI showed significant differences for detection of FBs in the three locations (P < 0.001). MRI could not locate iron samples due to severe artifacts and only showed their presence (bad visibility) but other FBs except for wood and tooth in the nasal cavity (100% invisible) had good visibility on MRI. CONCLUSIONS: Ultrasound is recommended as the first choice when FB is located within the superficial soft tissues with no bone around it. In case of penetration of FB into deeper tissues or beneath bone, CT or CBCT are recommended. Otherwise, considering lower dose, CBCT is preferred over CT. We can use MRI if the FB is not ferromagnetic. However, CT is the first choice in emergency situations because of higher sensitivity.

7.
Iran J Radiol ; 13(3): e34985, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27853499

RESUMO

BACKGROUND: Selecting a voxel size that yields minimal radiation dose with no significant compromise of the diagnostic accuracy of cone beam computed tomography (CBCT) is particularly important. OBJECTIVES: This study aimed to assess the effect of voxel size on detection accuracy of simulated external root resorption defects using NewTom CBCT system. MATERIALS AND METHODS: In this diagnostic study, the roots of 90 extracted human central incisors were hypothetically divided into cervical, middle, and apical thirds. Variable-size defects were prepared in the buccal and lingual surfaces of the roots and CBCT scans were obtained with four different voxel sizes (150, 200, 250, and 300). Presence or absence of defects on CBCT scans was determined by three radiologists and the results were compared with the gold standard (actual size and depth of defects). Sensitivity and specificity values were calculated and reported for different groups. RESULTS: In the lingual surfaces, the highest specificity and sensitivity belonged to 300µm voxel size (92.9%), and 200 and 250µm voxel sizes (both 97.4%) in the cervical third, respectively. In the middle third, the highest specificity and sensitivity belonged to 250 and 200µm voxel sizes (84.6% and 100%, respectively). In the apical third, the highest specificity and sensitivity belonged to 300 µm voxel size (100% and 97.9%, respectively). In the buccal surfaces, the highest specificity and sensitivity belonged to 150 (75.0%), 300 and 250 µm voxel sizes (100%) and the minimum values belonged to 200 µm voxel size (60% and 97.3%) in the cervical third. In the apical third, the highest specificity and sensitivity were noted in 300 µm voxel size (100% and 97.6%, respectively) and the minimum values were seen in 200 and 150 µm voxel sizes (93.8%, 90.5%, respectively). In the middle third, 300, 250 and 200 µm voxel sizes yielded the highest specificity (88.9%), while 150 µm voxel size yielded the highest sensitivity (98.8%). CONCLUSION: Considering the similar diagnostic efficacy of all voxel sizes, 300 µm voxel size can be used with adequate efficacy for detection of external root resorption defects with minimal patient radiation dose and the shortest scanning time.

8.
Dermatol Online J ; 22(1)2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26990467

RESUMO

BACKGROUND: Osteoma cutis is a rare soft tissue ossification of cutaneous tissue and may be primary or secondary. In the majorityof cases it is clinically asymptomatic and may detected incidentally on radiographic examination. Cone beam computed tomography (CBCT) has can be of great assistance in the detection of this asymptomatic lesion. OBJECTIVES: In this retrospective study, the prevalence and different radiographic appearance of osteoma cutis was evaluated. MATERIALS AND METHODS: A total of 6,500 CBCT images were evaluated for the presence of osteoma cutis. Ectopic existence of calcified tissue within the soft tissue of the dermis or epidermis that was incompatible with the calcification of other anatomic structures or soft tissue calcifications was considered to be osteoma cutis. Accordingly, the detected patterns were divided into four distinct groups: (1) a single nodule, (2) plate-like lesion, (3) single or multiple depth lesion(s), trans-epidermal, and (4) multiple, disseminated lesions of various sizes known as multiple miliary. The data were evaluated in terms of prevalence and variations. The frequency, total prevalence, percentage and the prevalence of different radiographic forms of this lesion were calculated. RESULTS: One hundred and forty eight (2.27%) cases of 6,500 evaluated tomograms had osteoma cutis. Of these, 5 (0.07%) were in the form of a single nodule, 4 (0.06%) were single, plate-like lesions, 7 (0.1%) were multiple plate-like lesions, 2 (0.03%) were in the form of a deep thread-like lesion, and 130 (2%) presented as multiple disseminated lesions. CONCLUSION: According to the radiographic views, osteoma cutis may be categorized into single nodular, single or multiple plate- like, deep, and multiple disseminated forms. Of the mentioned radiogarphic patterns, the multiple disseminated form (miliary) hada higher prevalence in our study. CBCT images enable accurate evaluation of the nature and frequency of osteoma cutis.


Assuntos
Neoplasias Ósseas/diagnóstico , Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias Faciais/diagnóstico , Imageamento Tridimensional/métodos , Osteoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Pele/diagnóstico por imagem , Adulto , Idoso , Neoplasias Ósseas/classificação , Neoplasias Faciais/classificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica , Osteoma/classificação , Neoplasias Cutâneas/classificação
9.
J Clin Diagn Res ; 9(11): TC04-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26675339

RESUMO

INTRODUCTION: Bitewing radiography is a valuable technique for assessment of proximal caries, alveolar crest and periodontal status. Technical errors during radiography result in erroneous radiographic interpretation, misdiagnosis, possible mistreatment or unnecessary exposure of patient for taking a repeat radiograph. AIM: In this study, we aimed to evaluate the efficacy of a film holder modified from the conventional one and compared it with that of conventional film holder. MATERIALS AND METHODS: Our study population comprised of 70 patients who were referred to the Radiology Department for bilateral premolar bitewing radiographs as requested by their attending clinician. Bitewing radiographs in each patient were taken using the newly designed holder in one side and the conventional holder in the other side. The acceptability of the two holders from the perspectives of the technician and patients was determined using a 0-20 point scale. The frequency of overlap and film positioning errors was calculated for each method. RESULTS: The conventional holder had greater acceptability among patients compared to the newly designed holder (mean score of 16.59 versus 13.37). From the technicians' point of view, the newly designed holder was superior to the conventional holder (mean score of 17.33 versus 16.44). The frequency of overlap was lower using the newly designed holder (p<0.001) and it allowed more accurate film positioning (p=0.005). CONCLUSION: The newly designed holder may facilitate the process of radiography for technicians and may be associated with less frequency of radiographic errors compared to the conventional holder.

10.
Iran J Radiol ; 12(3): e16059, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26557271

RESUMO

BACKGROUND: In orthodontic science, diagnosis of facial skeletal type (class I, II, and III) is essential to make the correct treatment plan that is usually expensive and complicated. Sometimes results from analysis of lateral cephalometry radiographies are not enough to discriminate facial skeletal types. In this situation, knowledge about the relationship between the shape and size of the sella turcica and the type of facial skeletal class can help to make a more definitive decision for treatment plan. OBJECTIVES: The present study was designed to investigate this relationship in patients referred to a dental school in Iran. PATIENTS AND METHODS: In this descriptive-analytical study, cephalometric radiographies of 90 candidates for orthodontic treatment (44 females and 46 males) with an age range of 14 - 26 years and equal distribution in terms of class I, class II, and class III facial skeletal classification were selected. The shape, length, diameter, and depth of the sella turcica were determined on the radiographs. Linear dimensions were assessed by one-way analysis of variance while the correlation between the dimensions and age was investigated using Pearson's correlation coefficient. RESULTS: Sella turcica had normal morphology in 24.4% of the patients while irregularity (notching) in the posterior part of the dorsum sella was observed in 15.6%, double contour of sellar floor in 5.6%, sella turcica bridge in 23.3%, oblique anterior wall in 20% and pyramidal shape of the dorsum sella in 11.1% of the subjects. In total, 46.7% of class I patients had a normal shape of sella turcica, 23.3% of class II patients had an oblique anterior wall and a pyramidal shape of the dorsum sella, and 43.3% of class III individuals had sella turcica bridge (the greatest values). Sella turcica length was significantly greater in class III patients compared to class II and class I (P < 0.0001). However, depth and diameter of sella turcica were similar in class I, class II, and class III patients. Furthermore, age was significantly correlated to the diameter of sella turcica as greater diameters were observed in older ages (P < 0.04). CONCLUSION: A significant relationship exists between the type of facial skeletal classification and the shape of the sella turcica; as in class III patients, sella turcica bridge was reported with a higher frequency. Also, sella turcica had a significantly higher length in these patients than in those with class I and class II facial skeletal types.

11.
Iran J Radiol ; 12(3): e25518, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26557283

RESUMO

Desmoplastic fibroma (DF) is a rare and locally aggressive intraosseous tumor with unknown etiology. The mandible is the common site of involvement in the maxillofacial region. However, it is believed that DF can arise in any bone of the body. A wide age distribution has been reported for DF occurrence, extending from birth to the sixth decade of life, with a peak incidence at 10 to 19 years of age. In this study, diagnostic and therapeutic management of a 6-year-old girl with a desmoplastic fibroma of the inferior orbital rim and zygomatic buttress are discussed. Cone beam computed tomography (CBCT) revealed a mixed lesion in infraorbital rim, which had ill-defined borders and a straight thick bony septum inside the lesion. It also involved the zygomatic process of maxilla and zygomatic bone. According to radiologic concepts, this rare lesion may mimic fibro-osseous, benign and especially malignant lesions. Regarding different treatment plans, identification of this lesion is essential. Furthermore, presence of coarse and irregular or straight septa along with some imaging criteria for malignant lesions such as destruction of the cortex, periosteal reaction and soft tissue invasion would be helpful to differentiate this lesion from malignant and multilocular benign lesions.

12.
Iran J Radiol ; 12(4): e16242, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26793287

RESUMO

BACKGROUND: Radiographs, adjunct to clinical examination are always valuable complementary methods for dental caries detection. Recently, progressing in digital imaging system provides possibility of software designing for automatically dental caries detection. OBJECTIVES: The aim of this study was to develop and assess the function of diagnostic computer software designed for evaluation of approximal caries in posterior teeth. This software should be able to indicate the depth and location of caries on digital radiographic images. MATERIALS AND METHODS: Digital radiographs were obtained of 93 teeth including 183 proximal surfaces. These images were used as a database for designing the software and training the software designer. In the design phase, considering the summed density of pixels in rows and columns of the images, the teeth were separated from each other and the unnecessary regions; for example, the root area in the alveolar bone was eliminated. Therefore, based on summed intensities, each image was segmented such that each segment contained only one tooth. Subsequently, based on the fuzzy logic, a well-known data-clustering algorithm named fuzzy c-means (FCM) was applied to the images to cluster or segment each tooth. This algorithm is referred to as a soft clustering method, which assigns data elements to one or more clusters with a specific membership function. Using the extracted clusters, the tooth border was determined and assessed for cavity. The results of histological analysis were used as the gold standard for comparison with the results obtained from the software. Depth of caries was measured, and finally Intraclass Correlation Coefficient (ICC) and Bland-Altman plot were used to show the agreement between the methods. RESULTS: The software diagnosed 60% of enamel caries. The ICC (for detection of enamel caries) between the computer software and histological analysis results was determined as 0.609 (95% confidence interval [CI] = 0.159-0.849) (P = 0.006). Also, the computer program diagnosed 97% of dentin caries and the ICC between the software and histological analysis results for dentin caries was determined as 0.937 (95% CI=0.906-0.958) (P < 0.001). Bland-Altman plot showed an acceptable agreement for measuring the depth of caries in enamel and dentin. CONCLUSIONS: The designed software was able to detect a significant number of dentin caries and acceptable measuring of the depth of carious lesions in enamel and dentin. However, the software had limited ability in detecting enamel lesions.

13.
Iran J Radiol ; 12(4): e25272, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26793289

RESUMO

BACKGROUND: Vertical root fracture (VRF) is a common problem in endodontically treated teeth. Due to its poor prognosis, a reliable technique must be used to make an accurate diagnosis. Cone beam computed tomography (CBCT) has been recently introduced for maxillofacial imaging. Despite the high diagnostic value of this method, metal artifacts resulting from intra-canal posts still make the detection of VRFs challenging. OBJECTIVES: This study aimed to assess the effect of object position in the field of view (FOV) of CBCT on detection of VRFs in teeth with intra-canal posts. MATERIALS AND METHODS: The crowns of 60 extracted premolar teeth were cut at the level of cementoenamel junction (CEJ). Root canals were filled with gutta-percha and filling of the coronal 2/3 of the root canals was subsequently removed to fabricate intra-canal cast posts. The teeth were randomly divided into two groups of 30. Fracture was induced in group one using an Instron machine. Group two was considered as the control group with no fracture. All teeth were then randomly positioned and scanned in five different positions starting at the center of the FOV as well as right, left anterior and posterior relative to the center (3, 9, 12, and 6 O'clock) via the New Tom VGI CBCT unit. Two observers evaluated images for VRFs. Sensitivity and specificity of fracture diagnosis in each position was calculated in comparison with the gold standard. Wilcoxon test was used for data analysis. RESULTS: Considering deterministic and probabilistic diagnostic parameters, probabilistic sensitivity was similar in all positions; but probabilistic specificity of the center position (65.1%) was significantly higher than that of 6 and 12 O'clock positions. Considering the deterministic diagnostic parameters, the overall sensitivity and specificity values decreased in all positions in FOV, but sensitivity of the center position of FOV was significantly higher than that of other positions; specificity was significantly higher at the 3 O'clock position (58.5%). CONCLUSION: Concerning the positions in FOV, the center position is suitable for detection of VRF in teeth with intra-canal posts due to significantly higher sensitivity at this position. The 3 O'clock position would be suitable for assessment of intact teeth without fractures due to significantly higher specificity at this position.

14.
Artigo em Inglês | MEDLINE | ID: mdl-22991626

RESUMO

BACKGROUND AND AIMS: With the introduction of Cone Beam Computed Tomography (CBCT) in dentistry, a question has been raised whether the technique significantly increases the diagnostic accuracy in comparison with other techniques or not. Therefore, the present study was undertaken to assess the accuracy of CBCT modality in detecting proximal carious lesions as compared to conventional periapical radiographs. MATERIALS AND METHODS: This diagnostic study was carried out on 84 human extracted molars and premolars. The teeth were mounted and divided in 28 blocks of 3 teeth. Periapical and CBCT images of teeth were obtained. Five observers scored the images for the detection of proximal carious lesions using a 2-point scale (caries, present; caries, absent). The gold standard was determined by histopathologic sections. Sensitivity, specificity, PPV, NPV and receiver operating charac-teristics (ROC) curves were traced for observers in both systems. The results were analyzed by paired t-test. RESULTS: The area under the ROC curve, sensitivity, specificity, accuracy, positive and negative predictive values of CBCT images were 0.568, 0.835, 0.637, 0.714, 0.598 and 0.856, respectively. These parameters were 0.432, 0.837, 0.722, 0.77, 0.687 and 0.858 for the periapical conventional technique, respectively. CONCLUSION: The CBCT images did not enhance detection of proximal caries in comparison with periapical images.

15.
Dent Traumatol ; 28(6): 478-82, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22340129

RESUMO

Root fracture diagnosis is a clinical difficulty that in most cases can only be detected through radiography. The objective of this study was to compare the diagnostic accuracy of two types of digitally enhanced images (reverse-contrast and colorization) with original digital radiographies in detecting experimental root fractures. Two hundred extracted single-rooted human teeth were endodontically instrumented and then divided in two groups, one control group and one test group, including fractured teeth. Vertical root fractures were experimentally made in the fractured group. The digital image of each tooth was taken, using the paralleling technique. There were three groups of images: (i) original, (ii) reverse contrast, and (iii) colorized. Three experienced dental specialists examined the images with no prior knowledge of the distribution of the root fractures. Two-way analysis of variance was used to assess the differences in accuracy, sensitivity, and specificity of each technique in detecting root fractures. Cohen's kappa coefficients were calculated to investigate the degree of interobserver agreement. The accuracy, sensitivity, and specificity of original images were 67.4%, 66.7%, and 68%, respectively; these amounts were 61.5%, 61%, and 65.5% in reverse contrast images and 66.4%, 70.7%, and 62% in colorized digital radiography. The original images had the best inter observer kappa coefficients (between 0.45 and 0.55). The results showed that the accuracy of original images is better than reverse contrast and colorized images. Use of reverse-contrast and colorization digital images in root fracture detection should be regarded as an adjunct to other diagnostic methods not as a highly critical diagnostic aid.


Assuntos
Intensificação de Imagem Radiográfica/métodos , Fraturas dos Dentes/diagnóstico por imagem , Raiz Dentária/lesões , Análise de Variância , Humanos , Variações Dependentes do Observador , Sensibilidade e Especificidade , Raiz Dentária/diagnóstico por imagem
16.
Iran J Radiol ; 10(1): 1-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23599706

RESUMO

BACKGROUND: Considerable variations in the development stage among patients of the same chronological age have led to introduce the concept of the developmental age based on the maturation of different organs such as cervical vertebrae or teeth. OBJECTIVES: The purpose of this study was to investigate the correlation between the stages of tooth calcification and the cervical vertebral maturation in Iranian females. PATIENTS AND METHODS: Four hundred females (age range, 8 to 14 years) participated in the study. To determine the dental maturational stage, calcification of the mandibular teeth except for third molars were rated according to the method suggested by Demirjian et al. To evaluate the stage of skeletal maturation, cervical vertebral morphologic changes were assessed on lateral cephalometric radiographs according to the method explained by Baccetti et al. Correlations between bone maturation and teeth calcification were showed by Spearman's correlation and Kendall's tau-b coefficients. The relevant associations were investigated by ordinal logistic regression models. RESULTS: Correlations between the two stages were observed in the first and second premolars, canine and central incisors. All these correlations were significant. The association between cervical vertebral maturation and tooth calcification was greatest in the lateral incisor (odds ratio (OR) = 11, 95% confidence interval (CI): 6.6-18.3). However, considering the 95% CI for OR, no significant difference was detected among the second molar, first molar and lateral incisor. CONCLUSION: The relationship between calcification of teeth and maturation of cervical bones was significant. Bone maturation can be predicted by using teeth calcification stages, especially in the second molar, first molar and lateral incisor.

18.
Artigo em Inglês | MEDLINE | ID: mdl-23230500

RESUMO

BACKGROUND AND AIMS: Digital radiographs have some advantages over conventional ones. Application of digital recep-tors is not routine yet. Therefore, there is a need for digitizing conventional radiographs. The aim of the present study was to compare the diagnostic accuracy of digitized conventional radiographs by scanner and camera in detection of proximal car-ies. MATERIALS AND METHODS: Three hundred and sixteen surfaces of 158 extracted posterior teeth were radiographed. The radiographs were digitized using a digital camera and a scanner. Five observers scored the images for the presence and depth of caries. Histopathologic sections were the gold standard. Kappa agreement coefficient was used for statistical analysis. RESULTS: Kappa agreement coefficients between the camera and the scanner and also between each one with the gold stan-dard in detecting the depth of caries were 0.504, 0.557 and 0.454, respectively. In detection of caries, the indexes were 0.571, 0.553 and 0.527, respectively. CONCLUSION: Diagnostic accuracy of camera images in caries detection was more than that of scanned images, but there was also a moderate consistency between them. The consistency of detecting the presence of caries was more than that of detecting their depths. It seems that both digital cameras and scanners can be used interchangeably.

19.
Artigo em Inglês | MEDLINE | ID: mdl-23277849

RESUMO

BACKGROUND AND AIMS: Radiography is used to diagnose the demineralization process and carious lesions; however, conventional radiography and direct digital images do not show these lesions when the amount of demineralization is less than 40%. Digital subtraction radiography has recently been used to improve the diagnostic quality of these le-sions. The purpose of this study was to compare the caries depth estimated by digital subtraction radiog-raphy in combination with barium sulfate in diag-nosing proximal dental caries with histopathologic evaluation. MATERIALS AND METHODS: In this study 30 molars and premolars (24 demineralized lesions with cavity, 8 without cavity) were studied. Direct digital images were taken (kVp: 68, mA: 8; t: 0.12 for premolars and t: 0.16 for molars) whereas the position of X-ray tube and CCD receptor and teeth was fixed. To prepare the second images 135 gr/L barium sulfate was used. The images obtained with the same exposure and geometry and then subtracted. The depth of the lesions in direct digital and subtracted images were assessed and compared with the depth measured in histopathologic assessments. RESULTS: The mean depths (± SD) of the lesions were 1.80 ± 0.77 mm in direct digital radiography, 2.32 ± 0.76 mm in subtracted images after barium sulfate treatment, and 2.51 ± 0.43 mm in histopathologic sections. The statistical difference between direct digital radiography and the other methods was significant (P < 0.05). However, the differences were not statistically significant between subtracted images and histopathologic sections. The average intra-class correlation coefficient was 0.7241 (CI: 95%). CONCLUSION: The present study has demonstrated that digital subtraction radiography images have the potential to measure the depth of proximal caries with no significant difference with histopathologic evaluation.

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