Evaluation of dehiscence and fenestration in adolescents affected by bilateral cleft lip and palate using cone-beam computed tomography.

INTRODUCTION: We evaluated the dehiscence and fenestration presence in maxillary and mandibular anterior teeth of patients affected by bilateral cleft lip and palate (BCLP) and compared the findings with a well-matched control group of noncleft patients using cone-beam computed tomography. METHODS: Cone-beam computed tomography images of 51 patients were divided into 2 groups (group 1, 21 patients affected by BCLP; mean age; 14.62 ± 2.89 years; and group 2, 30 patients as the noncleft control group; mean age, 14.22 ± 1.05 years) and assessed them for dehiscence and fenestration in the anterior maxillary and mandibular teeth. Data were analyzed with the Student t test, Pearson chi-square test, and Fischer exact test. RESULTS: The prevalences of dehiscence in patients affected by BCLP were 61.11% in the maxillary and 48.41% in the mandibular anterior teeth, whereas the rates in the noncleft group were 7.78% and 16.67%, respectively (P < 0.001). The presence of fenestration was found to be statistically significantly higher in the maxillary central incisors of the BCLP group compared with the noncleft controls (P < 0.05), and almost similar rates were noted for the other teeth, with no statistically significant differences (P > 0.05). CONCLUSIONS: Our data suggest that patients affected by BCLP may have higher prevalences of dehiscence in the maxillary and mandibular anterior teeth and of fenestration in the maxillary central incisors.

An Asymptomatic and Overelongated Styloid Process.

Elongation of the styloid process is a rare condition. Only 4% of patients have clinical symptoms where elongated styloid process (ESP) occasionally irritates or disrupts adjacent anatomical structures, which is called Eagle syndrome. This present report was aimed at reporting an asymptomatic ESP with unusual width and length.

Effects of impacted maxillary canines on root resorption of lateral incisors : A cone beam computed tomography study.

OBJECTIVES: The aim of this study was to analyze the amount of root resorption of maxillary lateral incisors by relating the position, location, and angulation of the impacted canine using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: The study sample consisted of panoramic and CBCT radiographs of 46 patients with a unilateral impacted canine (16 males and 30 females; mean age: 19.53 ± 6.66 and 19.44 ± 5.77 years, respectively). Sector location and canine angulation were measured in panoramics. All tomographs were obtained using CBCT (NewTom 5G, QR, Verona, Italy) and three-dimensional (3D) reconstructions of the maxillary laterals assessed by Mimics 14.01 image analysis software. RESULTS: Upper lateral incisor volume was smaller on the impacted side (401.95 ± 83.69 mm3) than on the nonimpacted side (433.54 ± 92.6 mm3, P < 0.05). There were no significant differences of lateral root resorption volume when comparing the impacted canines being on the labial or palatal sides (P > 0.05), but impacted canine angulation was significantly steeper on the labial side (70.85°) than on the palatal side (46.09°, P < 0.05). The volume of root resorption of laterals when comparing the various positions of the canine in different sectors or canine angulation in 30o intervals was not statistically significantly different (P > 0.05). CONCLUSIONS: The impacted canines caused root resorption of lateral incisors. The angulation of the canine was steeper on the labial side than on the palatal side but root resorption of adjacent laterals was not different. There were no statistically significant differences in the amount of root resorption of the laterals when the canine was evaluated according to localization and angulation.

Evaluation of the Transverse Craniofacial Morphology of Adolescents With Repaired Unilateral Cleft Lip and Palate Using Cone-Beam Computed Tomography.

AIM: The aim of the study was to evaluate the transverse craniofacial morphology of the adolescent patients affected by unilateral cleft lip and palate (UCLP) and to compare the findings with age- and sex-matched control group without any cleft using their cone-beam computed tomography (CBCT) images. METHODS: The study sample (n = 56 patients; mean age: 14.35 ±â€Š3.06 years) consisted of 26 UCLP (n = 26 patients; 10 women and 16 men; mean age: 13.70 ±â€Š2.94 years) and 30 control (n = 30 patients; 19 women and 11 men; mean age: 14.90 ±â€Š3.10 years) subjects. Twenty-five conventional skeletal and dental tissue landmarks were identified. Twenty widely used frontal cephalometric variables (14 linear distances, 3 angles, and 3 ratios) were measured. The data were analyzed using the independent t-test between the groups. RESULTS: Patients affected by UCLP had statistically significantly smaller interorbital width (89.83 ±â€Š4.16 mm), maxillary width (58.02 ±â€Š5.77 mm), maxillary intermolar width (52.83 ±â€Š4.83 mm), and upper face height (57.64 ±â€Š4.57 mm) (P < 0.05) compared with the control group. Conversely, ANS-isf distance was significantly greater in the UCLP group (29.62 ±â€Š5.19 mm) than in the control group (26.74 ±â€Š3.99 mm) (P = 0.023). Moreover, alveolar cleft width had significant effect on Cr-ANS (r = 0.446, P = 0.022) and the ANS-isf (r = 0.459, P = 0.018) measurements. CONCLUSION: The UCLP group showed statistically significantly smaller values for interorbital width, maxillary width, maxillary intermolar width, and upper face height than the noncleft controls.

C-shaped mandibular primary first molar diagnosed with cone beam computed tomography: A novel case report and literature review of primary molars' root canal systems.

Knowledge of the different anatomical variations in root canal system of dedicious dentition will improve the practice of the pediatric dentists. The teeth with C-shaped root canal configurations are definitely a problem in endodontic treatment. Dentists who are specialists of endodontics must have adequate knowledge about various root canal morphologies of primary tooth that have a tendency for rapid progression of dental caries to achieve a technically satisfactory outcome. This report presents an extraordinary case of unusual tooth morphology involving the mandibular first primary molar with a C-shaped configuration which has not yet been reported.

Evaluation of the Reliability of Cone-beam Computed Tomography Scanning and Electronic Apex Locator Measurements in Working Length Determination of Teeth with Large Periapical Lesions.

INTRODUCTION: This study evaluates the endodontic working-length measurements in teeth with large periapical lesions and persistent intracanal exudate by using preexisting cone-beam computed tomography (CBCT). It compares the measurements with clinical root canal lengths determined by using 2 electronic apex locators. METHODS: All patients had undergone a CBCT scan independent of the present study and needed root canal treatment of at least 1 tooth visible in the field of view. Seventy-three teeth with single roots and canals were studied. An endodontist measured each root canal length with 2 different electronic apex locators. The measurements were repeated 3 times by using a digital caliper, and the mean was recorded. This mean was compared with the root canal length as measured on CBCT sections by an oral radiologist not involved in the endodontic treatment. The CBCT measurements were taken twice for analysis of intrarater reliability. The data were statistically analyzed. RESULTS: There were no significant measurement differences between the methods used (P > .05). CONCLUSIONS: In teeth with large periapical lesions and persistent intracanal exudate, measurement of the root canal length by using CBCT was as reliable as measurements that used apex locators.

A novel PTCH1 gene mutation in a pediatric patient associated multiple keratocystic odontogenic tumors of the jaws and Gorlin-Goltz syndrome.

Gorlin-Goltz syndrome (GGS) is an uncommon autosomal dominant inherited disorder which comprises the triad of basal cell carcinomas (BCCs), odontogenic keratocysts, and musculoskeletal malformations. Besides this triad, neurological, ophthalmic, endocrine, and genital manifestations are known to be variable. It is occasionally associated with aggressive BCC and internal malignancies. This report documents a case of GGS with a novel mutation in the PTCH1 gene in an 11-year-old child. The clinical, radiographic, histopathologic and molecular findings of this condition, and treatment are described, and a review of GGS was carried out.

Genotypes and virulence factors of Candida species isolated from oralcavities of patients with type 2 diabetes mellitus.

BACKGROUND/AIM: This study compared the genotypes and virulence factors of Candida species isolated from oral cavities of healthy individuals and patients with diabetes mellitus (DM). MATERIALS AND METHODS: A total of 142 healthy individuals and 73 diabetic patients participated in this study. Study populations were classified into 4 groups as follows: Group I - Healthy, without caries; Group II - Healthy, with caries; Group III - DM, with caries; Group IV - DM, without caries. Diabetic patients' blood glucose and hemoglobin A1c concentrations were determined. Identification of Candida species was performed with conventional methods. Biofilm production, proteinase, phospholipase, and esterase were analyzed. The genetic diversity of Candida species was established using rep-PCR. RESULTS: The most isolated species was Candida albicans. There were statistical differences in terms of isolated Candida frequency between healthy subjects and diabetic patients. There was no statistical difference between the virulence factors of groups. Twelve genotypes were determined. While there were statistical differences in aerobe biofilm production, proteinase, and phospholipase activity between genotypes, there were no statistical differences in anaerobe biofilm production and esterase activity between genotypes. CONCLUSION: Diabetes has no effect on the activities of virulence factors of Candida species. Different genotypes of Candida albicans exhibited different virulence activities.

Role of cone-beam computed tomography in the evaluation of a paradental cyst related to the fusion of a wisdom tooth with a paramolar: A rare case report.

Fusion is an abnormality of tooth development defined as the union of two developing dental germs, resulting in a single large dental structure. This irregular tooth morphology is associated with a high predisposition to dental caries and periodontal diseases. As a result of recurring inflammatory periodontal processes, disorders such as periodontal pocket, pericoronitis, and paradental cysts may develop. A rare mandibular anatomic variation is the retromolar canal, which is very significant for surgical procedures. The fusion of a paramolar and mandibular third molar associated with a paradental cyst co-occurring with the presence of a retromolar canal is rare, and the aim of the present study is to describe the evaluation of this anatomical configuration using cone-beam computed tomography.

Evaluation of temporomandibular fossa and mandibular condyle in adolescent patients affected by bilateral cleft lip and palate using cone beam computed tomography.

The purposes of this study were to investigate the position of the mandibular condyle and temporomandibular fossa between the adolescent patients affected by bilateral cleft lip and palate (BCLP) and well-matched controls without any cleft by using cone-beam computed tomography (CBCT). The study sample consisted of 17 patients (7 females and 10 males; mean age, 14.27 ± 2.83 years) affected by BCLP and 17 patients (6 females and 11 males; mean age, 14.27 ± 2.12 years) as age-and sex-matched control group without any cleft. Using cone-beam computed tomography segmented three-dimensional temporomandibular fossa and mandibular condyle images were reconstructed and angular, linear, and volumetric measurements of the patients in both sides of the groups were examined using Paired and Student's t-tests. Comparison of the sides showed that both sides were found to be similar in BCLP and control groups, except the condylar angulation of the right side was found to be higher compared to that of the left side in both groups (p < 0.05). Comparison of the groups showed that the patients affected by BCLP and non-cleft patients had similar values for all parameters, except for the condylar angulation in the right side (BCLP group had less angulation compared to controls; p < 0.05). The condylar volume was found to be slightly less in the BCLP group in both sides compared to the controls (p > 0.05). The positions of the mandibular condyle and temporomandibular fossa were found to be similar in patients affected by BCLP and control group of without any cleft. SCANNING 38:720-726, 2016. © 2016 Wiley Periodicals, Inc.

Evaluation of root canal morphology of human primary molars by using CBCT and comprehensive review of the literature.

OBJECTIVE: Knowledge of primary tooth morphology is essential for clinical dentistry, especially for root canal treatment and dental traumatology. However, this has not been well documented to date with a large sample. This study was carried out to investigate the variation in number and morphology of the root canals of the primary molars, to study the applicability of cone beam computerized tomography (CBCT) in assessing the same and to provide a comprehensive review of the literature. MATERIALS AND METHODS: A total of 343 primary molars, without any root resorption, were divided into four main groups including the maxillary first molars, maxillary second molars, mandibular first molars and mandibular second molars. All of them were analysed in CBCT images in the axial, sagittal and coronal planes. Various parameters such as the number of roots, number of canals, the root canal type, diameter of root and root canal and root canal curvature were studied. RESULTS: Primary molars in all four groups showed variability in the number of roots and root canals. As far as length of the roots was concerned, the palatal root of the maxillary molar was found to be longest, while the distobuccal root was shortest. In mandibular molars, the mesial root was longer than the distal root. The length of distobuccal root canal of the maxillary molars and the distolingual canal of the mandibular molars was found to be shortest. The number of roots and root canals varied from two to four and three to four, respectively. The maxillary molars exhibited more one-canal than two-canal roots. CONCLUSION: The present study provides comprehensive information to the existing literature concerning the variation in root canal morphology of the maxillary and mandibular primary molar teeth. These data may help clinicians in the root canal treatment of these teeth.

Evaluation of the mandibular volume and correlating variables in patients affected by unilateral and bilateral cleft lip and palate: a cone-beam computed tomography study.

OBJECTIVES: The aims of the present study were to evaluate the mandibular volume in patients affected by unilateral (UCLP) and bilateral cleft lip and palate (BCLP) and to compare the findings with a well-matched normal occlusion sample without cleft. MATERIALS AND METHODS: The study sample consisted of 66 patients divided into UCLP (24 patients; mean age, 14.46 ± 3.24 years), BCLP (17 patients; mean age, 14.28 ± 2.85 years), and control (25 patients; mean age, 14.40 ± 2.81 years) groups. The volume of the mandible including the condyle and the roots of the teeth and craniofacial measurements were performed using cone-beam computed tomography and analyzed using the one-way variance analysis and post hoc Tukey's tests. Regression analyses were used to evaluate the relationships of the measurements and the mandibular volume. RESULTS: Patients affected by UCLP and BCLP had similar craniofacial features (p > 0.05), including decreased SNB, Co-A, Co-Gn, Co-Go, and Go-Gn and increased ANB and SN-MP measurements compared to the control group. Both UCLP and BCLP groups had decreased values of mandibular volume compared to the normal occlusion group, while these differences were found to be statistically insignificant (p > 0.05). Co-Go (Beta = 0.420; p = 0.014) and Co-Gn variables (Beta = 0.708; p = 0.045) were positively correlated with mandibular volume, while SNB (Beta = -0.669; p = 0.044) and SN-MP (Beta = -0.358; p = 0.049) variables were negatively correlated (R (2) = 60.3 and p = 0.000). CONCLUSION: Mandibular volume insignificantly differs in cleft patients (p > 0.05), and the variables of Co-Go, Co-Gn, SNB, and SN-MP significantly correlate with the volume. CLINICAL RELEVANCE: This article investigates mandibular volume in patients affected by UCLP and BCLP that has never been investigated in the literature. The present study showed that both UCLP and BCLP groups had insignificantly decreased values of mandibular volume compared to the normal occlusion group.

Evaluation of dehiscence and fenestration in adolescent patients affected by unilateral cleft lip and palate: A retrospective cone beam computed tomography study.

OBJECTIVE: To evaluate the presence of dehiscence and fenestration defects around anterior teeth in the cleft region and to compare these findings with the noncleft side in the same patients using cone beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT scans of 44 patients (26 males, 18 females; mean age, 14.04 ± 3.81 years) with unilateral cleft lip and palate (UCLP) were assessed to define dehiscences and fenestrations of the anterior teeth in both cleft and noncleft sides of the UCLP patients and a control group of noncleft patients (51 patients; 21 males, 30 females; mean age, 14.52 ± 1.16 years). Data were analyzed using Pearson's χ(2) and Student's t-test. RESULTS: The prevalence of dehiscences at the maxillary central incisors, lateral incisors, and canines teeth were 43.2%, 70.6%, and 34.1% on the cleft side and 22.7%, 53.1%, and 27.3% on the noncleft side of UCLP patients, and 13.7%, 7.8%, and 13.7% in controls, respectively (statistically no difference between the sides of cleft patients). The cleft patients had a statistically significantly higher prevalence of dehiscences than did the controls on both the cleft and noncleft sides (P < .05), except for the maxillary central incisors. Fenestrations for these teeth were significantly more common on the cleft side in UCLP patients compared with controls (P < .05), whereas the difference for maxillary lateral incisors was not statistically significant. CONCLUSIONS: Patients with UCLP showed a higher prevalence of dehiscence and fenestration defects around the maxillary anterior teeth.

Cone beam computed tomographic analysis of maxillary premolars and molars to detect the relationship between periapical and marginal bone loss and mucosal thickness of maxillary sinus

BACKGROUND: This study assessed the relationship between mucosal thickness (MT) of the maxillary sinus and periodontal bone loss (PBL) and periapical condition of related teeth. We also aimed to identify the association between root apices and the inferior wall of the maxillary sinus using Cone beam computed tomography (CBCT). MATERIAL AND METHODS: In this study, CBCT images of 205 patients with 410 maxillary sinuses were examined, retrospectively. A total of 582 maxillary molars and 587 premolars were observed. The relationship of each root with maxillary sinus and apical lesions of these roots were classified, PBL was examined and the situations of adjacent teeth were estimated. The effect of these conditions on sinus mucosal thickness (MT) was evaluated. RESULTS: There was a significant correlation between MT of maxillary sinus and both PBL and age (r = 0.52, p = 0.000 and r = 0.111, p= 0.002, respectively). The frequency of MT increased as the severity of apical lesion enlarged. A positive correlation was found between MT and degree of PBL and periapical lesions. To reveal the association between MT and pulpoperiapical condition bivariate correlation was done and a significant relationship between the pulpoperiapical condition and MT was found (r = 0.17, p = 0.000). CONCLUSIONS: This retrospective study showed that MT of the maxillary sinus was common among patients with PBL and MT was significantly associated with PBL and apical lesions. The relationship of maxillary sinus to adjacent teeth had also positive correlation with MT. CBCT imaging enabled better evaluation of maxillary sinus, posterior teeth and surrounding structures compared to other imaging tolos

Maxillary sinus volumes of patients with unilateral cleft lip and palate.

BACKGROUND AND OBJECTIVE: Studies about maxillary sinuses of cleft lip-palate patients have increased since sinusitis is commonly observed in these patients. It is evident that maxillary sinus will be morphologically affected in these patients. And anatomic differences may be a cause or at least a contributor of sinusitis. The aim of this study was to compare maxillary sinus volumes of the non-syndromic patients with unilateral cleft lip-palate and control group by using Cone-Beam computed tomography. METHODS: Tomography scans of 44 unilateral cleft lip-palate patients (18 right and 26 left) with age and gender matched 45 control patients were evaluated for the study. The images used in the study were part of the diagnostic records collected due to dental treatment needs. All tomographs were obtained in supine position by using Cone-Beam computed tomography (NewTom 5G, QR, Verona, Italy). The patient-specific Hounsfield values were set to include the largest amount of voxels in the sinuses volume calculation individually. All data were measured in mm(3). RESULTS: There was no statistically difference between the gender and age distributions of the groups. No statistically significant difference was found on the cleft and non-cleft side, the right and left side of the unilateral cleft lip-palate patients and the control group (P>0.05). For the inter group comparison, mean maxillary sinus volumes volume of unilateral cleft lip-palate patients (9894.55±4171.44mm(3)) was statistically smaller than the control group (11,977.90±4484.93mm(3)) (P<0.05). CONCLUSION: Maxillary sinus volumes were effected negatively in unilateral cleft lip-palate patients when compared with the healthy control group. No difference was found on the cleft, non-cleft side and the right-left side of the unilateral cleft lip-palate patients.

Cone beam computed tomographic analysis of maxillary premolars and molars to detect the relationship between periapical and marginal bone loss and mucosal thickness of maxillary sinus.

BACKGROUND: This study assessed the relationship between mucosal thickness (MT) of the maxillary sinus and periodontal bone loss (PBL) and periapical condition of related teeth. We also aimed to identify the association between root apices and the inferior wall of the maxillary sinus using Cone beam computed tomography (CBCT). MATERIAL AND METHODS: In this study, CBCT images of 205 patients with 410 maxillary sinuses were examined, retrospectively. A total of 582 maxillary molars and 587 premolars were observed. The relationship of each root with maxillary sinus and apical lesions of these roots were classified, PBL was examined and the situations of adjacent teeth were estimated. The effect of these conditions on sinus mucosal thickness (MT) was evaluated. RESULTS: There was a significant correlation between MT of maxillary sinus and both PBL and age (r = 0.52, p=0.000 and r = 0.111, p= 0.002, respectively). The frequency of MT increased as the severity of apical lesion enlarged. A positive correlation was found between MT and degree of PBL and periapical lesions. To reveal the association between MT and pulpoperiapical condition bivariate correlation was done and a significant relationship between the pulpoperiapical condition and MT was found (r = 0.17, p=0.000). CONCLUSIONS: This retrospective study showed that MT of the maxillary sinus was common among patients with PBL and MT was significantly associated with PBL and apical lesions. The relationship of maxillary sinus to adjacent teeth had also positive correlation with MT. CBCT imaging enabled better evaluation of maxillary sinus, posterior teeth and surrounding structures compared to other imaging tools.

Assessment of the alveolar bone support of patients with unilateral cleft lip and palate: a cone-beam computed tomography study.

OBJECTIVE: To assess the bone support of the teeth adjacent to a cleft using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: The CBCT scans of 31 patients with unilateral cleft lip and palate (UCLP) were assessed. The data for teeth neighboring the cleft were compared with those of contralateral noncleft teeth. For each tooth analyzed, the distance between the cementoenamel junction (CEJ) and the bone crest (AC) at the buccal side was measured as was the thickness of the buccal bone level at 0, 1, 2, and 4 mm. RESULTS: The bone thicknesses of the central teeth at the cleft region at the crest and 2 mm apically were statistically significantly thinner than that of the central incisor at a noncleft region. The CEJ-AC distance for central teeth at the cleft region was higher than that for central teeth in a noncleft region. CONCLUSIONS: Subjects with UCLP showed reduced bone support at teeth neighboring the cleft compared with controls. This may cause some problems during orthodontic treatment.

Unilateral bone cavities situated near the angle of the mandibula.

Stafne bone defects (SBDs) are asymptomatic radiolucent lingual/buccal bone lesions of the lower jaw and are frequently caused by soft tissue inclusion. These defects have a cystlike appearance on plain radiographs. The diagnosis of this defect is incidental because patients do not usually present clinical symptoms. The common variant of SBD exists at the third molar region of the mandible below the inferior alveolar canal. To date, only 1 case of multilocular SBD has been reported in the literature, including both clinical cases and archaeological specimens. The purpose of the current study was to describe a new case of multilocular appearance of SBD near the angle of the mandibula that was diagnosed with the aid of a three-dimensional cone beam computed tomographic scan.

Odontogenic tumors: a collaborative study of 218 cases diagnosed over 12 years and comprehensive review of the literature

OBJECTIVES: The objective of this study was to analyze the frequency and distribution of odontogenic tumors (OTs)in the Cappadocia region of Turkey, and to compare the findings with those reported in the literature. Study DESIGN: The records of the Oral and Maxillofacial Surgery and Pathology Departments at Erciyes University, with histologic diagnosis of odontogenic tumors (based on the World Health Organization classification,2005), over a 12-year period, were analyzed. The relative frequency of different types of tumors was also analyzed and compared with the literature. RESULTS: OTs in the present study constituted 2.74% of all the 7,942 registered biopsies. A total of 218 cases of OTs were collected and reviewed. Of these, (94.04%) were benign and (5.96%) were malignant. The mandible was the most commonly affected anatomic location, with 170 cases (77.9%). Ameloblastoma with a predilection for the posterior mandible was the most frequent odontogenic tumor (30.28%), followed by keratocystic odontogenictumor (19.5%), odontoma (13.4%), and odontogenic myxoma (8.5%).CONCLUSIONS: OTs are rare neoplasms and appear to show geographic variations in the world. In Cappadocia, Turkey, they are more common in the mandible, with ameloblastoma followed by keratocystic odontogenic tumors with the incidences observed in the present study being similar to those of previous studies from Asia and Africa, and in contrast to those reported from American countries

Evaluation of root morphology and root canal configuration of premolars in the Turkish individuals using cone beam computed tomography.

OBJECTIVE: The aim of the present study is to assess the root and root canal morphology of maxillary and mandibular premolars in a Turkish population by using cone beam computed tomography (CBCT). MATERIALS AND METHODS: In this study, CBCT images of 2134 premolars (987 maxillary, 1147 mandibular) were obtained from 404 patients. Details of gender, age, number of roots and canals, and canal configuration in each root were recorded. The canal configuration was classified and evaluated according to Vertucci's criteria. RESULTS: The majority of maxillary premolars had two separate roots; although, three roots were identified in 1% of maxillary first premolars. However, most of the mandibular premolars had a single root. The two canals (69.9%) and type I (62.6%) and type II (34.1%) configuration for upper first premolar, one canal (82.1%) and type I (77.6%) canal configuration for second premolar was the most prevalent root canal frequency. The most prevalent root canal frequency was the one canal (96.2%) and type I (94.2%) and type V (3.2%) configuration for mandibular first premolar, one canal (98.9%) and type I (98.9%) canal configuration for second premolar. There was no difference in the root canal configurations and the numbers of canals between the left and the right side of both females and males (P > 0.05). CONCLUSIONS: Recognition of morphology and anatomy of the root canal system is one of the most important factors for successful endodontic treatment. Preoperative CBCT examination allows determination of root canal configuration of premolar teeth and helps clinicians in root canal treatment.