جستجوی مقالات مرتبط با کلیدواژه "cone-beam computed tomography" در نشریات گروه "پزشکی"

 The middle mesial canal (MMC) of mandibular molars is of particular interest in endodontics due to its complexity. This study investigated the association between MMC presence in first and second mandibular molars and the radiolucency in the furcation area using cone-beam computed tomography (CBCT) scans. 

 CBCT scans of 400 patients referred to the largest radiology center in Kerman City from January 1, 2022, to January 1, 2023, were examined. All CBCT scans were assessed for radiolucency in the furcation area and the presence of MMC. Variables, including age, gender, tooth number, and MMC presence were recorded. Chi-squared tests and logistic regression analyses were employed to compare MMC frequency and its impact on furcation radiolucency. 

 Of 201 examined teeth, 37 (18.4%) had MMC, and 23 (11.4%) exhibited furcation radiolucency. However, teeth with a mesial canal showed a higher prevalence of furcation lesions compared to those without (38% vs. 5.2%) (P<0.001). A significant association was observed between a mesial canal and furcation radiolucency, with odds of furcation radiolucency at 12.7 after controlling for age and gender (P<0.001). 

 A strong association exists between MMC presence in first and second mandibular molars and furcation radiolucency, unaffected by age and gender.

Taurodontism is a dental anomaly characterized by the absence of cervical constriction at the cemento-enamel junction, apical shifting of the pulpal floor, and an expanded pulp chamber. This condition presents unique challenges in endodontic diagnosis and treatment due to its variable morphology, deeply located orifices, and complex root canal system. This paper reports three cases of hypertaurodontism (Taurodont Index ≈ 50), including a maxillary first molar, mandibular third molar, and mandibular second premolar in systemically healthy patients. The identification and treatment planning were facilitated by cone-beam computed tomography (CBCT). Root canal therapy was performed under a dental operating microscope, with careful exploration, chemomechanical instrumentation using rotary files, copious irrigation with 5.25% sodium hypochlorite, and warm vertical obturation. Twelve months later, follow-up visits showed that all patients were clinically and radiographically asymptomatic, indicating successful outcomes. Taurodontism presents significant challenges due to its anatomical complexities. A multifaceted approach involving CBCT, dental operating microscopes, ultrasonic irrigation, and warm vertical obturation is recommended. This case series demonstrates that with advanced diagnostic aids and meticulous techniques, even hypertaurodontic teeth can be effectively managed.

The present study aimed to assess the frequency, Lingual Concavity Angle (LCA) and the different types of lingual concavity in the posterior mandible. In this study Cone Beam Computerized Tomography (CBCT) images of 670 mandibular bodies in the molar areas were evaluated. Cross-sectional images of the mandible were reconstructed at furcation points of first molar area. The LCA was measured. The subjects with LCA smaller than 85° were considered as concave. Then, the concave subjects were classified into three groups: angle less than 40°, angle between 40-60°, and angle between 60-85° were designated as extremely deep, deep, and mild deep, respectively. The most common type of lingual concavity was mild deep, followed by deep, and extremely deep. There was a significant positive correlation between the LCA and the age of participants (p<0.001). There was also significant relationship between the age of participants and the type of lingual concavity (p<0.001). The subjects in mild deep group were significantly older than deep group (p=0.032). Also, the non-concave subjects were significantly older than deep and mild deep subjects. (p=0.001 and 0.040, respectively). The LCA was significantly higher in males than females (p=0.020). The LCA was significantly larger on the left side (p<0.001).  The presence of deep lingual concavity was common (95%.). Also, mandibular lingual concavity types were found to vary by age, and laterality. Moreover, the LCA was significantly different according to patient age, sex, and laterality.

Understanding the characteristics of the pterygoid hamulus (PH) is crucial for diagnosing and treating various oropharyngeal and craniofacial conditions. It also aids in interpreting radiographs and diagnosing unexplained oropharyngeal pains. Cone-beam computed tomography (CBCT) is a valuable tool, offering clinical insights into this previously understudied area. Accordingly, this study aimed to evaluate the morphology and dimensions of the PH and its changes by ageing in 20-40-year-old women in the Dental Branch of Islamic Azad University of Sciences, Tehran, Iran.

  This cross-sectional study was conducted on CBCT scans from 258 women aged 20-40. The morphology, length, width, and angle of the PH in coronal and sagittal planes were investigated.

The average length of the right and left hamulus was 5.50±1.37 and 5.37±1.36 mm. The average width of the right and left hamulus was 2.16±0.72 and 2.11±1.06 mm. The average coronal angle of the right and left hamulus was 22.3±9.79° and 30.16±8.99°. The average sagittal angle of the right and left hamulus was 26.11±7.26° and 26.34±7.63°. In contrast with the sagittal angle, the right and left hamulus’s length, width, and coronal angles were not symmetrical. Slender morphology was the most frequent morphology, and it was symmetrical only in the 20-30-year-old age group. Finally, no variable was affected by ageing.

  Hamulus dimensions and morphology did not change with ageing in women aged 20-40. The PH symmetry varied by age group. Also, CBCT was a suitable tool for investigating hamulus changes.

Endodontic success mainly depends on the complete root canal system debridement, both mechanically and chemically. The maxillary first molar possesses one of the most complex root canal anatomy. The purpose of this study was to map the maxillary first molar's root canal anatomy and its variations. Cone Beam Computed Tomography (CBCT) was used to determine the prevalence of the Second Mesiobuccal Canal (MB2) and its possible relation to the gender of the patient in the Iraqi population.

Images from documented archives of CBCT scans for 415 patients who had maxillofacial diagnosis or root canal treatment were used in this study. Totally 656 maxillary first molars (336 females and 320 males) were included. The root canal configuration, frequency of MB2, and its two-sided symmetry were observed. The (chi-square test) was used to calculate the gender correlation. The P-value of less than 0.05 (p < 0.05) was considered significant.

In 61.1% of the cases, the MB2 canal was discovered with high bilateral symmetry (73.6%). Genders did not show any statistically significant differences.

The existence of MB2 canal in the maxillary first molars is high and approximately more than half of the cases. No relation was found between the existence of the MB2 canal and the gender of the patient. CBCT is a clinically efficient method for the diagnosis and improvement of root canal therapy.

Invasive cervical resorption (ICR) is an aggressive pathological condition that can affect any permanent tooth. This process is characterized by replacement of the tooth structure with granulomatous fibrovascular or fibro-osseous tissue. Despite its asymptomatic nature, ICR can lead to tooth loss. This study reports a case of ICR in a 15-year -old boy with a history of dental trauma. The patient had a diagnosis of ICR in tooth #21. After considering the risks of an external surgical approach and exclusive endodontic treatment, intentional re-implantation combined with extraoral composite resin restoration and endodontic treatment was proposed. The procedure consisted of atraumatic tooth extraction, removal of granulomatous tissue, restoration of the cavity with composite resin, re-implantation of the tooth in the alveolus, and endodontic treatment. This approach resulted in satisfactory repair of the resorptive lesion observed in over 3 years of follow-up. This case highlights intentional re-implantation combined with appropriate endodontic treatment as a viable treatment option for ICR.

 The removal of impacted lower third molars surgically can cause complications, and the lingual cortical bone thickness in this region becomes a determining factor in the risk of perforation and injury to the lingual nerve (LN). This study was conducted to assess the relationship between different angulations of impacted lower third molars based on Winter’s classification and the thickness of the lingual cortical bone. Variations in lingual cortical bone thickness among the genders were evaluated as well.

 Cone-beam computed tomography (CBCT) scans of 50 impacted lower third molar teeth of 50 patients (26 men and 24 women) were evaluated in this study. The lingual bone thickness surrounding impacted lower mandibular teeth was measured at three key points, namely, the cemento-enamel junction of the second mandibular molar, the mid-root of the impacted third molar, and the root apex of the impacted third molar. Mesiodistal angulation and buccolingual angulations of the impacted mandibular third molars underwent investigation. Statistical analysis was conducted using SPSS 23. Data were analyzed using the independent sample t test, one-way ANOVA, multiple linear regression analysis, and Fisher’s exact test.

 There was a statistically significant relationship between the means of lingual cortical bone thickness surrounding the third molars based on Winter’s classification of third molars impacted at mesiodistal angulation (P=0.00). Regarding gender, buccolingual angulation demonstrated a statistically significant relationship among the means of lingual bone thickness around the third molars (P=0.022).

 In our study, the thickness of the lingual cortical bone was notably affected in the middle and apical areas of the impacted third molar region. The variable position of the LN near the mandible third molar region was significant in dental procedures due to its proximity. Three-dimensional (3D) imaging CBCT provides preoperative risk assessment that reduces preventable complications that cannot be answered by 2D imaging.

Root canal obturation length may significantly affect the development of apical periodontitis lesions. This study aimed to investigate the prevalence of periapical periodontitis and its relationship with previous root canal treatment in terms of root canal obturation length.

In this cross-sectional observational study, 264 root canal-treated premolars and molars from patients referred to the Faculty of Dentistry at Azad University of Isfahan, who had undergone root canal treatment at least one year prior, were examined using CBCT radiography. A total of 630 canals with previous root canal treatments were selected. The screening protocol involved an initial selection of roots, followed by alignment in three planes (coronal, sagittal, axial) to ensure centrality. The roots were then classified based on the presence of periapical periodontitis and obturation length. Data analysis was conducted using Fisher’s exact test (α=0.05).

There was no significant difference between quality of obturation length among root treated teeth in all study groups (p>0.05). Significant difference was observed between the obturation length and the frequency of apical periodontitis. The lesions among canals with proper obturation length were significantly less than canals with under or over obturation (p<0.001). But no significant difference was shown in pairwise comparison of each teeth type. (molars -premolars, first- second) (P>0.05).

There was a relationship between the length of root canal obturation and the prevalence of apical periodontitis, with a significantly lower presence of lesions in canals with appropriate obturation. However, this relationship was not observed based on the type of teeth.

This study aimed to assess the accuracy of age estimation by pulp/tooth area ratio (PTR) of maxillary canine teeth on cone-beam computed tomography (CBCT) scans.

This descriptive analytical study was conducted on 99 CBCT scans of patients between 18 to 71 years with fully erupted sound maxillary canine teeth. The CBCT scans were evaluated in five sections namely the mid-sagittal section, mid-coronal section, and axial planes [cementoenamel junction (CEJ) section, root section at one-quarter distance from the CEJ, and mid-root section] using OnDemand software. The tooth and pulp surface areas and PTR were calculated. The absolute error of age estimation was calculated by the regression test. 

In females, PTR of the CEJ section (-0.338) and one-quarter root section of the axial plane (-0.459; P=0.003 and P=0.000, respectively), and in males, PTR of the mid-root section of the axial plane (-0.346) and mid-sagittal section (-0.455; P=0.013 and  P=0.002, respectively ) had significant correlations with age. The mean absolute error of age estimation in the present method, compared with the chronological age of individuals, was 7.227 years. In 39.5% of the cases, the obtained regression formula could estimate age with less than 5 years difference. No significant difference was noted in age estimation for males and females in this method.

It appears that PTR on CBCT images of maxillary canine teeth has a significant correlation with chronological age.  The obtained formula in this study could estimate age with acceptable accuracy (less than 7.5 years).

Errors that occur during root canal treatment can be caused by lack of information about the anatomical conditions of the root canal system. The purpose of this study was to examine the root and ca-nals morphology of mandibular anterior teeth using cone-beam computed tomography (CBCT).

In this descriptive analytical study, 165 CBCT images of mandibular anterior teeth of patients from 15 to 60 years in the archives from oral & maxillofacial radiology department in 2015-2021 were used. CBCT images were examined in three axial, sagittal and coronal sections and the infor-mation of each tooth were recorded in pre-prepared forms. The data were analysed by Chi-square and Fisher exact test (α=0.05).

All mandibular central teeth were single-rooted, of which 59.7% were single canal and 40.3% were double-canal. 99.4% of the mandibular lateral teeth were single-rooted and 0.6% of the teeth were double-rooted. 62.8% of single-rooted laterals had a single-canal where 37.2% had double-canals. 97.6% of canine teeth were single-rooted and 2.4% of teeth were double-rooted. In single-rooted teeth, 95.3% had a single-canal. In mandibular single-rooted anterior teeth with two canals, Vertucci type III was the most common configuration. The frequency distribution of the variation of mandibular central and lateral teeth canals between women and men were not statistically significant, while in single-rooted canines significant differ-ences were observed (p= 0.031).

Anterior teeth with two roots was not common. It was more prevalent in canines, laterals and central teeth. The prevalence of single-rooted mandibular teeth with two canals was mostly seen in central, lateral, and canine teeth.

In this study, Cone-Beam Computed Tomography (CBCT) was used to assess the dimension and posture of the tongue, as well as Alveolar Bone Thickness (ABT) and labiolingual inclination of mandibular central incisors in order to look for any correlations.  A total of 200 CBCT images of skeletal Class I and II individuals were studied. Each group of malocclusion was divided into three subgroups: low-angle, normal-angle, and high-angle. Buccal and lingual alveolar bone thickness (BT & LT), and the Inclination of Mandibular Plane Angle (IMPA) were measured and compared by using T-test. The spearman rank correlations test analyzed the correlations between dental variables and tongue measurements (p<0.05).  Significant weak correlations were identified between dental variables and tongue measurements. In Cl I malocclusion, IMPA and Tongue Length (TGL) were found to be significantly correlated with a correlation value of 0.324 (p=0.001). In Cl II malocclusion, there was a significant correlation between BT3 and TGH. About BT3, there was a significant correlation with D4’ and a negative correlation with D5’. Further comparison among vertical subgroups revealed the same results.  Class I patients with superior tongue posture may have thicker lingual alveolar bone around mandibular incisors and Class II patients showed that thicker labial alveolar bone of  lower incisor and thinner alveolar bone at the lingual side may be associated with a superior position of the posterior portion of the tongue.

This work analyzed the efficacy of Cone-Beam Computed Tomography (CBCT) enhanced scan in evaluating the therapeutic effect and prognosis of interventional therapy in patients with liver cancer (LC).

Eighty-two individuals diagnosed with primary LC were enrolled here and grouped according to the intraoperative treatment. Patients in group A were only treated with digital subtraction angiography (DSA) during the operation, while those in group B received DSA and CBCT during the operation. The operation time, radiation dose, detection rate of tumor lesions, and lipiodol deposition were compared between two groups.

In group A, 54 lesions were identified before operation, 48 lesions during intraoperative angiography, and 6 lesions remained undetected. In group B, 57 LC lesions were identified before operation, and 57 lesions during intraoperative CBCT enhanced scan, and 2 small LC lesions not presented previously were detected. The number of lesions with complete lipiodol precipitation in group B (42) was clearly higher as against group A (32) (P < 0.05). The operation time of group B was clearly longer as against group A (P < 0.05), but there existed no substantial difference in radiation dose patients in different groups (P > 0.05).

The results indicated that CBCT enhanced scan was superior to conventional DSA in detecting tumor    lesions, nutrient arteries, and lipiodol deposition in patients undergoing LC chemoembolization. Importantly, this enhanced method did not increase radiation dose but prolonged the operation time.

 This study assessed the correlation of tongue posture with dental arch characteristics in sagittal and vertical skeletal patterns using cone-beam computed tomography (CBCT).

 This cross-sectional study evaluated 225 CBCT scans of sagittal Class I, II, and III patients. Class I and II groups were subdivided into high-angle, normal, and low-angle vertical subgroups. Palatal length, width, and height, maxillary width (Wmax), mandibular width (Wman), tongue posture according to the Graber’s analysis, tongue length (TGL), and tongue height (TGH) were three-dimensionally measured. Statistical analyses were conducted using one-way and two-way ANOVA, and Pearson and Spearman tests (alpha=0.05).

 All dental arch parameters were significantly greater in Class III, compared with Class I and II groups (P<0.05), except for) Wman, palatal length, and palatal height( . Palatal height was significantly greater in Class II and III, than Class I group (P<0.05). Wmax was lower in high-angle than low-angle, and palatal length was lower in high-angle than low-angle and normal groups (P<0.05). In Class I normal-angle patients, Wmax had a positive correlation with TGL. In Class I low-angle patients, Wmax had a moderate positive correlation with TGH.

 Significant differences were found in Wmax and palatal length among the vertical groups. In different skeletal patterns Wmax, Wman had a low to moderate positive correlations with D4, D5, D5ʹ, TGL and TGH. Wmax in Class I was significantly lower than that in Class III; this variable in Class II was significantly lower than that in Class III

This study aimed to assess the changes in alveolar ridge dimensions following immediate implantation with and without buccal gap filling using cone-beam computed tomography (CBCT).

This prospective randomized clinical trial was conducted on 15 patients (mean age = 44.7 years) with 26 hopeless teeth. The teeth were extracted and immediately replaced with implants. The patients were randomly assigned to two test and control groups (N=13 implants each). In the test group, the gap around the implants was filled with allograft, while the control group did not receive buccal gap filling. CBCT scans were obtained at twodays and fourmonths postoperatively. The buccolingual ridge dimensions, buccal plate thickness, and buccal gap distance were measured at the implant platform and 2 and 4 mm apical to it, and changes were analyzed by the mixed-effects model (alpha = 0.05).

In cases with a sound buccal plate having a minimum thickness of one millimeter, the alveolar ridge and buccal plate resorption werethe same in the test and control groups.

The results revealed that immediate implantation with and without buccal gap filling did not prevent alveolar ridge and buccal plate resorption

Untreated canals represent the primary cause of treatment failure in molars and the second leading cause in other dental groups. This study determined the prevalence of untreated canals and their relationship with periapical periodontitis using cone -beam computed tomography (CBCT) images.

385 CBCT images with at least one treated canal were selected from the oral and maxillofacial radiology center. The number of roots and canals, presence, and size of periapical pathology, and presence of untreated canals were recorded. The study used descriptive statistics and Chi -square, Fisher's exact, and odds ratio tests to analyze data.

Of the 2053 teeth examined, 14.9% had at least one untreated canal. Untreated canals in teeth increase the chance of having a periapical lesion, raising the prevalence by 11 times. Of these, 91.8% had both untreated canals and periapical lesions. This was more than teeth without untreated canals (35.8%). Most untreated canals were in maxillary molars (65.3%), and mandibular molars (12.54%). There was a statistically significant relationship (P<0.001) between the number of roots, canals, expansion, destruction, and jaw type with the prevalence of untreated canals. The maxillary first molar (68.66%) and second mesiobuccal (MB2 ) canal (63.27%) had the highest percentages of untreated canals.

The MB2 had the highest prevalence of untreated canals. The presence of untreated canals significantly increased the risk of expansion and/or destruction. Therefore, identifying these conditions can also be useful in diagnosing untreated canals .Dentists should assess the anatomy of the tooth and the structure of the root canal to minimize the possibility of an untreated canal. CBCT can assist in this process.

The posterior superior alveolar artery (PSAA) is a branch of the maxillary artery. This study compared the anatomical position of the PSAA in the maxillary sinus between edentulous and dentate patients using cone-beam computed tomography (CBCT).

This descriptive study evaluated 280 maxillary sinus CBCT scans of edentulous and dentate patients. Visibility, vertical diameter, location and type of artery, horizontal distance from the PSAA to the sinus internal wall, distance from the artery to the sinus floor, distance from the artery to the alveolar crest, and distance from the alveolar crest to the sinus floor were studied on coronal sections using SIDEXIS 3D software. Data were analyzed by the Chi-square, Spearman rank correlation coefficient, and independent t tests. 

The artery type was mainly type I, with no difference between males and females or edentulous and dentate patients (P>0.05). PSAA was primarily located in the second molar area in dentate patients. The horizontal distance from the PSAA to the sinus internal wall, PSAA vertical diameter, distance from the alveolar crest to the sinus floor, and distance from PSAA to the maxillary sinus floor were not different in different age groups (P>0.05). Vertical diameter of PSAA and distance from PSAA to the maxillary sinus floor were not different between edentulous and dentate groups (P>0.05).

The distance from the PSAA to the sinus internal wall and to the alveolar crest, and the distance from the alveolar crest to the sinus floor were smaller in edentulous patients.

Successful endodontic treatment depends on completely clearing, shaping, and filling the prepared canals. Knowledge of the common and aberrant varying pulp anatomies is essential for suitable root canal treatment. Since, this anatomy is complex and varies morphologically in different populations. This study aims to determine the number of roots, canals, and evaluation of mandibular premolars canals using cone -beam computed tomography (CBCT) images in one of Iran's northern provinces (Golestan).

CBCT axial, coronal, and sagittal slices of two hundred and twelve mandibular premolars were analyzed to determine the number of roots and canals based on Vertucci type. The images were analyzed in a one-millimeter slice in mesiodistal and buccolingual dimensions based on gender. The data were analyzed using the Chi-score test to compare the components if the defaults were not established. A significance level of 0.05 was considered.

Of the two hundred twelve teeth evaluated, 130 (61.3%) were first premolars, and 82 (38.6%) were second premolars. Most first premolars (78.5%) and almost all second premolars (97.6%) had one root. Morphological types of root canals were identified based on Vertucci’s classification types I, II, III, IV, V, or VIII, and type I was the most frequent. There were no significant associations between number of roots and sex (P>0.05).

Mandibular premolars mostly had one root and type I Vertucci morphology. The frequency of two-canal premolars was higher in the male population. Although the abundance of two or three roots with different morphologies was also observed, the possibility of the presence of an additional root canal should be considered