Evaluation of the effect of the inversion filter on enhancing the visibility of the mandibular incisive canal in comparison with the original images.

BACKGROUND: The mandibular incisive canal (MIC) is a neural canal containing one of the lower branches of the inferior alveolar nerve, called the mandibular incisive nerve, which can get damaged and cause complications during the removal of bone from the interforaminal region. OBJECTIVES: The aim of this study was to determine the effect of the inversion filter (IF) on improving the visibility of MIC as compared to the original images. MATERIAL AND METHODS: In this retrospective, descriptive, analytical study, 343 samples of digital panoramic radiography were examined. The images were analyzed with and without IF. The frequency and confidence intervals (CIs) of identifying MIC were used to determine its visibility, both with IF and in the original images. Besides, the difference between the maximum and minimum diameters of the canal as well as the distance from MIC to the alveolar crest and to the mental foramen were examined. For statistical analysis, McNemar's test and the paired t-test were used, and the concordance was calculated using the kappa coefficient. RESULTS: No significant differences were found in the prevalence of the incisive canal, or in its unilateral or bilateral visibility between the original and filtered radiography in this study (p = 0.42 and p = 0.67, respectively). The absolute values of the interval difference between MIC and the mental foramen, the maximum and minimum diameters of MIC, and the distance from MIC to the alveolar crest were statistically significant between the filtered and original radiography, although the difference was clinically unimportant. CONCLUSIONS: The use of IF produced results similar to the original radiography; its application neither increased the clarity nor improved the visibility of the incisive canal.

Evaluation of the gray level of restorative materials using cone-beam computed tomography: A cross-sectional study.

BACKGROUND: Densitometry plays an important role in the diagnosis and treatment planning. Due to diversity in density, equal amounts of different materials absorb various amounts of X-rays and yield different radiographic views. OBJECTIVES: The aim of this study was to evaluate the gray scales of 5 commercially available restorative materials, including amalgam, composite resin, flowable composite resin, glass-ionomer, and Dycal. MATERIAL AND METHODS: Samples of the 5 test materials from various manufacturers were prepared, each 5-millimeter-thick. There were 7 glass-ionomer samples and 10 of each of the other materials, making a total of 47 samples in the study. The test materials were scanned using a Kodak cone-beam computed tomography (CBCT) unit. Subsequently, the gray scales were determined and evaluated by a radiologist using OnDemand3DTM Dental software and analyzed with SPSS v. 22 software. RESULTS: Amalgam had a higher gray scale than the other groups of restorative materials. In some cases, it was the same as that of composite resin; however, it was significantly different from gray scales of flowable composite resin, glass-ionomer and Dycal. It was concluded that composite resin and amalgam were high in gray scale, while flowable composite resin, glass-ionomer and Dycal exhibited low gray scales. CONCLUSIONS: Amalgam and composite resin had high gray scales, and glass-ionomer and Dycal exhibited the lowest gray scale values. The findings show that CBCT can be helpful in differentiating amalgam and composite resin from other materials.

Assessment of digital panoramic radiography's diagnostic value in angular bony lesions with 5 mm or deeper pocket depth in mandibular molars.

BACKGROUND: Assessment of alveolar bone level in periodontitis is very important in determining prognosis and treatment plan. Panoramic radiography is a diagnostic tool used to screen patients. The aim of the present study was to assess the diagnostic value of digital panoramic radiography in angular bony defects with 5 mm or deeper pocket depth in mandibular molars. MATERIALS AND METHODS: In this cross-sectional study, ninety angular bony defects in mandibular molars teeth with 5 mm or deeper pocket depth were selected in sixty patients with the diagnosis of chronic periodontitis. Before surgery, bone probing was performed. During the surgery, the vertical distance from cementoenamel junction to the most apical part of bony defect was measured using a Williams probe and this measurements were employed as gold standard. This distance was measured on the panoramic radiographs by a Digital Calliper and Digital Ruler. All data were compare dusing independent samples t-test and Pearson's correlation coefficient. RESULTS: No significant difference was found between the results of bone probing and intra-surgical measurements (P = 0.377). The mean defect depth determined by Digital Caliper and Digital Ruler on panoramic radiographs was significantly less than surgical measurements (P < 0.001). The correlation between bone probing and surgical measurements in determining the defect depth was strong (r = 0.98, P < 0.001). Radiographic measurements made by Digital Ruler (r = 0.86), comparing to Digital Caliper (r = 0.79), showed a higher degree of correlation with surgical measurements. CONCLUSION: Based on this study, bone probing is a reliable method in vertical alveolar bone defect measurements. While the information obtained from digital panoramic radiographs should be used with caution and the ability of digital panoramic radiography in the determination of defect depth is limited.

An Analysis of Visibility and Anatomic Variations of Mandibular Canal in Digital Panoramic Radiographs of Dentulous and Edentulous Patients in Northern Iran Populations.

STATEMENT OF THE PROBLEM: Insufficient information about the anatomical positions and structure of mandibular canal provokes unwanted damage to this important structure of mandible. PURPOSE: The aim of this study was to determine the visibility and anatomical variations of mandibular canal in digital panoramic radiographs of dentulous and edentulous patients in a sample of Iranian population. MATERIALS AND METHOD: In this retrospective-analytical research, 249 digital panoramic radiographs in dentulous group and 126 in edentulous group were studied by an expert oral and maxillofacial radiologist. In both groups, the visibility of canal borders in anterior, middle, and posterior areas were examined. In dentulous group, the distance between the canal and apex of the first and second molars were measured. Canal-to-alveolar crest distance and lower mandibular border was measured in three different points for both groups. Finally, the upper-lower positions of canals were determined. RESULTS: In both groups, most visibility occurred in 1/3 of posterior and the least visibility was detected in 1/3 of anterior, with the intermediate being the most visible part (Type 2). There was no significant difference between the left and right sides in all cases. In dentulous group, no correlation was found between the visibility, age, and gender (p> 0.05); however, canal position was related to gender (p= 0.03 and p= 0.04 in right and left sides, respectively). High position was more frequent in females and intermediate position was more common in males. In edentulous group, no correlation was found between age, gender, and canal position (p> 0.05). CONCLUSION: The most visibility of mandibular canal was in its third posterior and the least was in its third anterior part. Although the middle position of canal was more frequently visible than the high position in this study, it does not refute the possibility of damaging the mandibular canal in critical surgeries.

The Effects of Septal Deviation, Concha Bullosa, and Their Combination on the Depth of Posterior Palatal Arch in Cone-Beam Computed Tomography.

STATEMENT OF THE PROBLEM: Nasal breathing is the major pattern of air intake. Changes in breathing pattern alter the posture of the head, jaws and tongue that could change pressure on the jaw and teeth and affect their growth. PURPOSE: This study aimed to investigate the relationship between septal deviations (SD) per se and in combination with concha bullosa (CB) on maxilla; particularly the depth of palatal arch. MATERIALS AND METHOD: This descriptive-comparative study was performed on 116 cone-beam computed tomography (CBCT) images. The images were categorized into four groups (n=29) as follows; group 1: SD+CB, group 2: only SD, group 3: neither SD nor CB, and group 4: only CB. In coronal images, deviated septal length (DSL), angle of deviated septal curve (DSCA), palatal arch depth (PAD), palatal interalveolar length (PIL), PAD/PIL ratio, septal vertical length (SVL), maxillopalatal arch angle (MPAA), interjugum distance (IJD), and jugum angle (JA) were measured. The data were statistically analyzed with Tukey's HSD and Chi-square tests. RESULTS: There were statistically significant differences in DSL and DSCA (p= 0.0001) among the four groups. The study groups were not statistically different regarding the IJD, JA, MPAA, PAD/PIL, PAD, PIL, and SVL. However, in group 1, PAD/PIL were significantly correlated with DSCA and DSL (p= 0.037, and p= 0.043, respectively). CONCLUSION: Based on the findings of this study, simultaneous occurrence of SD and CB influenced the depth and curve of the palatal bone. The PAD/PIL ratio was negatively correlated with the DSCA angle. This correlation was associated with a decrease in PAD, indicating that concurrent occurrence of SD and CB remarkably affected the palatal base of maxilla.

Nucleated red blood cells count in pregnancies with idiopathic intra-uterine growth restriction.

OBJECTIVE: Elevated nucleated red blood cell (NRBC) count is introduced as a potential marker of intra-uterine growth restriction (IUGR). To investigate the probable association regardless of any known underlying disease, we aimed to study disturbances in NRBC count in infants experiencing idiopathic IUGR. MATERIALS AND METHODS: Twenty three infants regarded IUGR without any known cause were chosen to be compared to 48 normal neonates. Blood samples were collected instantly after birth and the same measurements were done in both groups. RESULTS: NRBC count/100 white blood cells was significantly higher in the IUGR group (P value < 0.001). pH measurements did not reveal any significant difference. CONCLUSION: Increased NRBC count in cases of idiopathic IUGR in absence of chronic hypoxia could strengthen its predictive value suggested in previous studies. It could help early IUGR detection and beneficial intervention.