Cone-beam Computed Tomography Data Research Articles

A Novel Approach to Repositioning and Stabilization of a Luxated Tooth With Displacement Using a 3D Printed Guide

The management of traumatic dental injury aims at functional and esthetic rehabilitation. After luxation injury, a displaced tooth must be replaced into its normal position as soon as possible. Incorrect tooth repositioning can cause discomfort to the patient and compromise the outcome. This report documents a novel digital technology–based approach for the management of teeth following luxation injury with displacement. A 25-year-old female reported 2 days after traumatic dental injury to her maxillary right central incisor tooth #8. After clinical and radiographic examination, a diagnosis of lateral luxation of tooth #8 was made. The preoperative high-resolution cone-beam computed tomography (CBCT) image data set confirmed palatal luxation of tooth #8 with fractured and displaced labial cortical plate. The CBCT data were imported into a medical image processing software program, and a segmentation tool was used to segment the fractured cortical plate, luxated tooth, and alveolar process. The socket is reconstructed by realigning fractured cortical bone over the alveolar process and repositioning the tooth in the virtual planning software. A three-dimensional (3D) guiding template was designed over the repositioned tooth and adjacent teeth and printed. This 3D printed guide was used for the repositioning of luxated tooth #8 and stabilizing it during the splinting procedure. This technique of using CBCT and 3D guide for repositioning is an objective, precise, and predictable approach. The 3D printed model of the dental arch after virtual tooth alignment can be used by the dentist to determine the exact splint length and contour before splinting.

Comparison of the accuracy (trueness and precision) of virtual dentofacial patients digitized by three different methods based on 3D facial and dental images

Statement of problemThe accuracy of virtual dentofacial patients has been explored, but the accuracy of virtual patients established by using a straightforward and reliable method and the accuracy of different virtual patients are unclear. PurposeThe purpose of this clinical study was to compare the accuracy of virtual dentofacial patients digitized by using registered-block impression, exposed anterior teeth, and cone beam computed tomography (CBCT) reconstruction methods based on 3-dimensional (3D) facial and dental images. Material and methodsFrom the 15 selected participants who needed CBCT scanning, 3 kinds of virtual dentofacial patients were established by using 3 registration methods based on digital dental casts: 3D facial images, CBCT data, and registered-block impression. Compared with actual measurement, 25 linear distances of all virtual dentofacial patients were selected and measured by using a software program, and 3 separate measurements were calculated by the same person. The 1-way analysis of variance (ANOVA) was used to compare the deviations among 3 kinds of virtual dentofacial patients (trueness) and the deviations within groups (precision). The 1-sample t test was used to compare the difference between the deviation and the ideal error of 0.00 (α=.05). ResultsCompared with the actual measurement, the trueness of the average deviations for registered-block impression (1.02 ±1.24 mm) was better than that of exposed anterior teeth (2.35 ±1.71 mm) and CBCT reconstruction (2.86 ±1.61 mm). The precision of the average deviations for registered-block impression (1.29 ±1.43 mm) was better than that of exposed anterior teeth (2.00 ±1.72 mm) and CBCT reconstruction (2.12 ±1.94 mm). Significant differences in trueness and precision were found among the 3 groups of virtual dentofacial patients (P<.01). Significant differences among the deviations of all linear distances and the ideal error of 0.00 were observed for all groups of virtual dentofacial patients (P<.05). ConclusionsThe accuracy of registered-block impression was better than that of the exposed anterior teeth and CBCT reconstruction. The accuracy of exposed anterior teeth was lower than that of the other methods but could satisfy the requirements of clinical diagnostics and scientific methods. The accuracy of CBCT reconstruction was poor and could only be used for special situations that permitted low accuracy.

Photobiomodulation and Stem Cell on Repair of Osteoporotic Bones

Objective: This study examined the use of photobiomodulation (PBM) plus adipose-derived stem cells (ASCs) to enhance the osteogenic properties of demineralized bone matrix (DBM) scaffold in a critical size femoral defect (CSFD) of ovariectomy-induced osteoporotic (OVX) rats. Background: PBM could be used as a unique strategy to enhance the osteogenic potential of DBMs seeded with ASCs. Materials and methods: The OVX rats with a CSFD were divided into six groups: (1) Control (C); (2) DBM scaffold alone (S); (3) S+PBM; (4) S+alendronate; (5) S+ASC; (6) S+PBM+ASC. Stereological analysis, real-time polymerase chain reaction (RT-PCR), and cone-beam computed tomography (CBCT) were performed after euthanization at 4 and 8 weeks postimplantation surgery. Results: In the 8th week, Groups 4 and 6 showed a greatly high new trabecular bone volume than the scaffold group (all, p = 0.009). The CBCT data demonstrated that the CSFD was significantly smaller in the two, three, and six groups relative to the control group (p = 0.01, p = 0.000, and p = 0.000, respectively). RT-PCR revealed that Groups 3 and 6 had higher messenger RNA levels of osteocalcin (OC) and osteoprotegerin (OPG) compared with the control group (p = 0.05). Group 6 had significantly lower expression of receptor activator of nuclear factor-κB ligand (RANKL) compared with the control group (p = 0.02). Conclusions: The combination of DBM plus PBM plus ASC, as well as DBM plus PBM significantly improved the healing of CSFD in OVX rats, and affected the expression of OPG, OC, and RANKL genes.

The Role of Cone-Beam Computed Tomography in the Imaging Guided Implantology with Surgical Stent for Dental Implants Placement _ a Case Report

Three-dimensional imaging, particularly cone-beam computed tomography (CBCT), has made significant contributions to the planning and placement of implants of missing tooth or at immediately removed tooth. The accuracy of CBCT data can be used to fabricate a surgical guide that transfers the implant planning information to the surgical site to facilitate implant placement. Prosthetically driven implant prosthesis assures good aesthetics, function and more importantly hygiene maintenance enabling long time success. Accuracy in treatment planning and implementation of planned treatment is vital for this success. Here we describe a method for applying CBCT data to aid in the planning and placement of implant using CBCT data to aid in planning and placement of Missing and immediate extracted tooth implant.

EXAMINATION OF THE RELATIONSHIP BETWEEN CONCHA BULLOSA WITH NASAL SEPTUM DEVIATION AND MAXILLARY SINUS PATHOLOGIES USING CONE-BEAM COMPUTED TOMOGRAPHY

ABSTRACT Objective: To evaluate the relationship between concha bullosa (CB) and nasal septum deviation (NSD) with maxillary sinus pathologies with cone-beam computed tomography (CBCT). Materials and Methods: The whole face CBCT data of 700 (383 male and 317 female) patients aged between 6-92 years who applied to Gaziantep University Faculty of Dentistry Department of Dentomaxillofacial Radiology for any reason between 2017-2019 was evaluated retrospectively. CB, NSD and maxillary sinus pathologies were investigated on the images. Results: NSD was found as 64.3%, concha bullosa as 27.9% on the right, 24.1% on the left, and maxillary sinus pathologies were 48.6% on the right and 44.4% on the left. While NSD was towards the left, the absence of right concha bullosa was found to be significant (p &amp;lt; 0.05). No significant relationship was observed between the presence of CB and maxillary sinus pathologies (p &amp;gt; 0.05). There was no significant relationship between NSD and maxillary sinus pathologies (p &amp;gt; 0.05). Conclusion: There was a significant relationship between the presence of CB and NSD, but the presence of CB had no effect on maxillary sinus pathologies. CBCT is an important diagnostic tool in the evaluation of the anatomical variations of the osteomeatal complex and three-dimensional examination of maxillary sinus.

A randomized controlled trial: evaluation of efficiency and safety of a novel surgical guide in the extraction of deeply impacted supernumerary teeth in the anterior maxilla.

BackgroundPreoperative X-ray and cone-beam computed tomography (CBCT) are helpful for locating supernumerary teeth, but the images cannot be transferred to the operation. To design a novel surgical guide plate for intraoperative navigation, we transfer the patient’s oral CBCT and gypsum model scan data to a computer for analysis. In our study, we evaluate the efficiency and safety of a novel surgical guide plate for the extraction of deeply impacted supernumerary teeth (DIMSNT) in the anterior maxilla.MethodsForty patients treated at the Department of School & Hospital of Stomatology, Wenzhou Medical University from March 2019 to December 2020 with DIMSNT (type II/III according to Liu et al.) in the anterior maxilla were randomly divided into 2 groups (20 patients for each group) for the extraction. For group I, a novel surgical guide was selected using CBCT and gypsum model scan. In contrast, for group II who underwent freehand surgery, only the CBCT data was used. The evaluation of operation time, complications, satisfaction score, and the number of cases that underwent extraction immediately after removing the bone were performed to assess the efficiency and safety of this novel surgical plate.ResultsAll patients completed the surgery successfully. The guides for group I had a good application effect. Group I’s operation time (23.35±5.39 min) was shorter than group II (29.60±9.76 min) (P=0.0194). The average pain degree of group I (1.8±1.08) was significantly less than group II (2.82±1.68) (P<0.05). The average swelling score of group I (34) was significantly less than group II (44.7). Patient satisfaction was significantly higher in group I (8.95±1.05) than in group II (7.90±1.51) (P=0.0152).ConclusionsThe novel surgical guide assisted with DIMSNT extraction have been effective in improving the quality of the surgery, patient satisfaction, and reduce its difficulty and duration. We can construct a surgical guide plate to guide the incision and osteotomy in DIMSNT surgery through the data analysis of DIMSNT on computer, which has a broad application prospect for clinical use.Trial registrationChinese Clinical Trial Registry ChiCTR2100054523.

Three-dimensional perception of cinematic rendering versus conventional volume rendering using CT and CBCT data of the facial skeleton

The aim of this exploratory study is to analyse whether three-dimensional cinematic rendering image reconstructions offer advantages over conventional volume rendering in the visualisation of cone beam computed tomography (CBCT) and computed tomography (CT) images of the facial skeleton. This is of interest, as some information gets lost during the rendering process. This especially applies to structures in the background of the image and some surface information which can be lost. The commonly applied two-dimensional representation of CBCT or CT images in three different axes requires experience for interpretation. Cinematic rendering is a new three-dimensional post processing reconstruction technique, creating photo realistic visualisations, thus possibly enabling an easier interpretation of the images.In this study, ten investigators assessed ten separate patient cases of the orofacial skeleton. For each case, a conventional volume rendering image reconstruction and a cinematic rendering reconstruction of the same area was created. A specially designed questionnaire assessed both objective and subjective criteria of image perception. Objective criteria were assessed by predefined questions on the visual perception of anatomical image characteristics, showing the two reconstruction types of each case randomly to the investigators in two sessions. Subjective criteria were assessed via a visual analogue scale, showing both reconstructions simultaneously in a third session.The results show that cinematic rendering offers advantages especially in the evaluation of depth perception and three-dimensionality. Volume rendering shows advantages in surface sharpness. Cinematic Rendering was subjectively rated higher for almost all reconstructions. The cinematic rendering process however may cause loss of information and blurring of surfaces compared to volume rendering. With respect to the subjective impression, cinematic rendering scored better than volume rendering. The visualisation is perceived as being very close to reality.

Periodontal probing on digital images compared to clinical measurements in periodontitis patients

The aim of the study was to compare the supra-alveolar gingival dimension (GD) and the clinical pocket probing depth (PD) by combining data from an intraoral scanner (IOS) and cone-beam computed tomography (CBCT) and identify the clinical features affecting the clinical PD. 1,071 sites from 11 patients were selected for whom CBCT, IOS images, and periodontal charts were recorded at the same visit. CBCT and IOS data were superimposed. GD was measured on cross-sectional images of the probed sites. The level of agreement and correlation between GD and PD were assessed for the entire population and within groups (treated vs untreated, bleeding on probing [BOP] vs no BOP, and PDs of 0–3 mm vs 4–5 mm vs ≥ 6 mm). The mean [± SD] difference between GD and PD was 0.82 [± 0.69] mm, and they were positively correlated (r = 0.790, p < 0.001). The correlations between GD and PD were stronger for untreated sites, sites with BOP, and sites with a larger PD. Within the limitations of this study, the similarity between GD and PD may suggest a possible tendency of overestimation when recording PD.

A novel method of superimposing dentition on cone beam computed tomography images of the palatal mucosa coated with barium sulphate

ABSTRACT Purpose This study examined the accuracy of the superimposition of dentition on cone-beam computed tomography (CBCT) images using palatal mucosa with and without barium sulphate coating. Materials and Methods The heads of six slaughtered pigs (six months old) were used. Intraoral digital models of the upper molars and palatal and segmented data from CBCT images with and without barium sulphate coating were acquired from samples. We performed superimposition of intraoral digital models using the palatal soft-tissue portion to compare the superimposition errors between segmented data from CBCT with and without barium sulphate coating. Errors were calculated as the distances between the dentulous areas of the digital model and CBCT data. Results The average error of the superimposition with barium sulphate coating was 0.35 mm, and the maximum was 7.45 mm. When CBCT was performed without the palate being coated with barium sulphate, the average error was 2.16 mm with a maximum of 14.3 mm. Errors when CBCT images were obtained using barium sulphate were significantly smaller than when using uncoated images (p = 0.02). Conclusions A novel and non-invasive method for accurately superimposing an intraoral digital model on CBCT images based on palatal mucosa coated with barium sulphate was developed.

A novel dental reconfigurable drilling guide based on standardized drilling sleeves and personalized substrate

Drilling guide that consists of a personalized substrate and additional guide sleeves has been widely used to precisely position the implants in dental surgery. However, the traditional drilling guide cannot be reused or disassembled because the guide sleeves are affixed in the substrate. Additionally, the guide sleeves are not as wearable as they are made of titanium. In this paper, based on standardized drilling sleeves and a personalized substrate, a novel dental reconfigurable drilling guide is proposed, which is beneficial to ensure the accuracy of implant insertion. The drilling sleeves are installed in the substrate through transition fit and can be easily disassembled. First, the three-dimensional model of mandible was reconstructed based on the cone beam computed tomography data. Secondly, according to the implant planning from the dentist, the drilling sleeves were designed based on the diameter of special drills. The drilling sleeves was used in conjunction with the special drill. Thirdly, different substrates were designed through medical image processing software based on the oral cone-beam computed tomographic data. Afterwards, the designed drilling sleeves and substrates were manufactured by means of computer numerical control machining and three-dimensional printing, respectively. Finally, the reconfigurable drilling guide was formed by installing the standardized drilling sleeves in different substrates. The results were demonstrated that the standardized drilling sleeves can be reused in different substrates for different drilling guides. Reusing the reconfigurable drilling sleeves economizes medical materials, reduces the time to prepare the drilling guide, and simultaneously achieves prospective precision in the implant placement.

Management of pulp canal obliteration using static-guided endodontic technique: Case series

The present case series aims to describe the management of teeth with pulp canal obliteration (PCO) using the novel static-guided endodontic technique. Traumatic dental injury may result in partial or complete PCO, with and without periapical rarefaction and pose challenges during endodontic management. Three young adolescent patients presented to the department with a chief complaint of pain/discoloration/broken upper front teeth. The teeth were tender on percussion. Thermal and electrical pulp tests were negative for the concerned incisors. The periapical radiographic examinations revealed PCO and signs of periapical changes. A diagnosis of pulp necrosis; symptomatic apical periodontitis was established and nonsurgical endodontic treatment using the guided endodontic approach was planned with the patient consent. A cone-beam computed tomography (CBCT) scan and intraoral scanning were obtained using the special software to facilitate guided endodontics procedure. The surgical guides and a customized drill were fabricated. The drilling depth for the access to the calcified part was established using CBCT data, ensuring straight-line access. Conventional root canal treatment was completed. One-year follow-up examination revealed the absence of pain and periapical healing. In complicated cases with PCO and apical periodontitis, a CBCT and “Guided Endodontics” could be useful to save the tooth with minimal destruction of tooth structure and increase the chances of endodontic success.

Morphological Variations of the Posterior Mandible: Proposing a Classification for Ridge Morphology Based on Cone-Beam Computed Tomography Data.

This study sought to assess the morphological variations of the posterior mandible and propose a classification for ridge morphology based on cone-beam computed tomography (CBCT) data. This retrospective, cross-sectional study evaluated 130 CBCT scans of patients with edentulous mandibles. Qualitative variables including lingual and crestal concavity, vertical, horizontal and angular limitations, and ridge morphology were assessed at 631 sites on CBCT scans of 87 males and 43 females. A classification for ridge morphology in the posterior mandible was proposed based on the collected data. The kappa coefficient was calculated to assess the intra-observer agreement, and data were analyzed using the chi-square test and Pearson's correlation test. The frequency of lingual concavity increased from the anterior towards the posterior region relative to the mental foramen (P < 0.05). The maximum frequency of lingual concavity (11.1%) was noted at 21 mm distance from the mental foramen while its minimum frequency (4.1%) was noted at 5 mm from the mental foramen (P < 0.05). Ridge morphology, defined as ridge angulation < 15°, no lingual or crestal concavity, no limitation in width, and 8-10 mm height, had the highest frequency. Its suggested treatment plan included a 10-mm implant without width limitation or severe angulation. The majority of common morphologies had no width limitation with ridge angulation < 15°. Height limitation was only present in two of them, which can be resolved by placement of a short implant or ridge augmentation.

The study of bone healing after endodontic microsurgery using cone beam computed tomography: A retrospective cohort study.

BackgroundThe main aims of this study were to evaluate mean volume reduction, radiographic healing rate and healing outcome two years after endodontic microsurgery. The effects of certain preoperative clinical factors upon preoperative volume, volumetric changes and healing outcome were also studied. Material and MethodsA clinical database was searched for patients who had undergone endodontic microsurgery and with the availability of a cone beam computed tomography (CBCT) scan preoperatively and after a control period. Volumetric analysis of the periapical area was made to assess volumetric reduction. The modified Penn 3D criteria were applied. The relationship between preoperative volume, volumetric reduction and healing outcome and certain preoperative factors was also studied. ResultsFifty-seven cases were evaluated. Initially, the bone cavities had a median volume of 163.2 mm3, and this volume decreased by 147.7 mm3 after treatment, with a radiographic healing rate of 6.2 mm3 per month. After applying the modified Penn 3D Criteria, 53 cases were classified as successful healing (93%). Regarding the influence of the different preoperative factors, patient age and sex, dental arch and cortical bone significantly influenced preoperative volume, while only the dental arch exerted a significant influence upon volumetric changes and preoperative symptoms on healing outcome. ConclusionsThe CBCT data evidenced a significant volume reduction of 79.1%, with a monthly volume reduction rate of 6.2 mm3. The success rate obtained was 93%. Patient age and sex, dental arch and cortical bone influenced preoperative volume, tooth type had an impact upon the volumetric changes, and the preoperative symptoms influenced healing outcome. Key words:Cone beam computed tomography, endodontic microsurgery, healing, lesion volume, prognostic factors.

Stress and Strain Created Around Miniscrews during En Masse Retraction - A Finite Element Method.

Background:En masse retraction of the anterior teeth may create anchorage problems. The effective means of obtaining anchorage in en masse retraction is by the usage of temporary anchorage devices.Aims and Objectives:The purpose of this study is focused on stress and strain created around miniscrew during en masse retraction using the cone beam computed tomography (CBCT) data obtained at two intervals and by the finite element analysis done using the CBCT data obtained. This will show us the stress and strain created around miniscrews and the withstanding capacity of miniscrews.Conclusion:Stress and strain was higher in TADs as compared to cortical and alveolar bone.

Evaluation of paranasal sinus anatomic variations and mucosal changes with cone beam computed tomography

Background/Aim: Anatomical variations of paranasal sinuses are common and play an role in disrupting the drainage of the sinuses, which often causes chronic sinusitis. In this article, anatomical variations of the paranasal sinuses and its relationship with mucosal changes were evaluated retrospectively by cone beam computed tomography (CBCT) which is also known as dental volumetric tomography. Material and Methods: CBCT data of 500 patients who applied to Cukurova University Faculties of Dentistry for any reason were retrospectively evaluated by maxillofacial radiologist. Anatomical variants of paranasal sinuses were included in the study. Mucosal thickening greater than 2 mm in the maxillary sinus was considered pathological. Results: The most common anatomic variation in the study was the nasal septal deviation, found in 302 (60.4%) patients. The least common anatomic variation in the study was lower concha pneumatization found in 3 (0.6%) patients. Mucosal thickening of the maxillary sinus was observed in 271 (54.2%) cases in the right sinus and 260 (52%) cases in the left sinus (p&gt;0.05). Conclusions: Nasal septum deviation was the most common variation in the study. According to the results of our study, concha bullosa, haller cell and the uncinate process had no definite effect on mucosal thickening in the maxillary sinus.

Algorithms for orthodontic treatment of patients with maxillary constriction based on the stages of formation of the palatal suture

Improving the effectiveness of complex orthodontic treatment of patients with constriction and deformation of the upper jaw during the period of replacement and permanent bite based on the analysis of cone-beam computed tomography (CBCT) data. The results of complex treatment of 70 patients with constriction and deformation of the upper jaw during the period of temporary and permanent bite are presented. The patients were divided into groups according to the stage of formation of the midpalatal suture: 1st group - 40 patients with stage «A» and «B» (average age 11.5 years); 2nd group - 15 patients with stage «C» (average age 20.5 years); 3rd group - 15 patients with stage «D» and «E» (average age 24.5 years). Orthodontic treatment was carried out using palatine expanders with a dental and intraosseous type of fixation. The complex treatment consisted of: orthodontic treatment using a bracket system, transgingival laser corticotomy, piezocorticotomy, surgically assisted rapid palatal expansion, orthodontic appliances for the expansion of the upper jaw. After conducting a clinical X-ray examination of all patients and analyzing the data obtained, we developed algorithms for therapeutic measures. As a result of the diagnosis and treatment planning, the expansion of the upper jaw was achieved both at the dental alveolar and skeletal levels. Detailed algorithms of complex treatment were developed based on the analysis of CBCT data, the stage of formation of the midpalatal suture individually for each patient. It was found that the analysis of CBCT data makes it possible to choose the optimal treatment method for patients with skeletal deformities of the dentition complex, thereby increasing the effectiveness of orthodontic treatment.

Do two- and three-dimensional imaging show the same risk of nerve injury during extraction of mandibular third molars depending on their angulations and distances to the inferior alveolar canal? – A retrospective clinical study over 8 years

ObjectivesInjury of the inferior alveolar canal (IAC) is a common complication during mandibular third molar (MTM) surgery. The aim of this study was to compare the MTM risk assessment using orthopantomography (OPG) and cone beam computed tomography (CBCT) images showing different MTM angulations and distances to the IAC. Materials and methodsThis retrospective study investigated 388 lower third molars of 259 patients radiologically over eight years using OPG and CBCT. Measurement and categorisation of MTM position showed four different types of angulations: vertical (type 1), mesioangular (type 2), horizontal (type 3) and distoangular (type 4). The shortest distance from the MTM and the IAC was measured and categorized after a risk classification (class 1–3) for injury of the IAC. ResultsHigh risk (class 1) was detected in 38.4%, moderate risk (class 2) in 21.9%, and low risk (class 3) in 36.1% using OPG data. In CBCT, high risk (class 1) was found in 11.6%, moderate risk (class 2) in 5.7%, and low risk (class 3) was fount in 78.6%. The same risk classification for OPG and CBCT was present in 25.1% of cases. The most common angulation was type 1 in 49.7%, followed by type 2 in 40.5%, 5.2% in type 3, and 4.4% in type 4. ConclusionPreoperative CBCTs are essential for risk evaluation and treatment planning in MTM surgery due to differences in OPG and CBCT data regarding nerve injury risk.

Multi-Projection Segmentation on Dental Cone Beam Computed Tomography Images Using Level Set Method

Segmentation of dental Cone-beam computed tomography (CBCT) images based on Boundary Tracking has been widely used in recent decades. Generally, the process only uses axial projection data of CBCT where the slices image that representing the tip of the tooth object have decreased in contrast which impact to difficult to distinguish with background or other elements. In this paper we propose the multi-projection segmentation method by combining the level set segmentation result on three projections to detect the tooth object more optimally. Multiprojection is performed by decomposing CBCT data which produces three projections called axial, sagittal and coronal projections. Then, the segmentation based on the set level method is implemented on the slices image in the three projections. The results of the three projections are combined to get the final result of this method. This proposed method obtains evaluation results of accuracy, sensitivity, specificity with values of 97.18%, 88.62%, and 97.61%, respectively.

Three-dimensional inlay-guided endodontics applied in variant root canals: A case report and review of literature

BACKGROUNDRoot canal retreatment is common after root canal therapy in clinical situations. Especially, completing the retreatment of variant root canals can be challenging. This is particularly true for the molars located at the end of the dental arch. However, advancements in digital dental diagnosis and treatment techniques can solve these problems. Here, we describe a case of a maxillary second molar with a variant distobuccal root canal treated via a novel “inlay-guided endodontics” technique based on improved computer-generated programs. CASE SUMMARYA 63-year-old man complained of a defect in the maxillary left second molar. The tooth, diagnosed with post-treatment endodontic disease, was initially treated by conventional methods, which were ineffective. Our “inlay-guided endodontics” technique was subsequently adopted, with the establishment of a precise integrated three-dimensional (3D) plate model of cone-beam computed tomography data and a digital impression of the dentition. An optimal root canal approach was generated for the “virtual file” in the 3D model. The plate data were imported into a 3D printer and printed. With the help of the guide plate, the file was accurately placed into the cervical third of the distal root canal. The root canal and prosthodontic treatments successfully proceeded subsequently. CONCLUSIONOur newly developed inlay guide plates may facilitate individualized and minimally invasive root canal treatment.

Modern approaches to the elimination of artifacts of cone-beam computed tomography of the maxillofacial region

The use of X-ray radiation is the main additional method for complete visualization of hard and soft tissues in dentistry and maxillofacial surgery. Cone-beam computed tomography (CBCT) is of leading importance among other methods. Three-dimensional reformation of CBCT data into a multiplanar or three-dimensional image of anatomical structures allows for a qualitative assessment of the area of interest and to choose the right treatment tactics if necessary. Nevertheless, there are a number of factors or artifacts that lead to distortion, disrupt the image or lead to loss of information during CBCT, in addition, the formation of overdiagnosis is not excluded. Currently, an active search is underway for ways to improve the quality of CBCT images and eliminate artifacts to improve the quality of diagnostics. This review is devoted to the description of the main causes of artifacts and modern methods of their elimination.