Cone Beam Computed Tomography Research Articles

Efficacy of the Coronoid Notch and Occlusal Plane As Predictable Landmarks for Determining the Medial Cut Height in Bilateral Sagittal Split Osteotomy: A Split-Mouth Observational Study.

This split-mouth observational study was conducted to assess the reliability and safety of using the coronoid notch and occlusal plane as landmarks to aid surgeons during bilateral sagittal split osteotomy(BSSO). Thirteen patients between the ages of 18 and 30 years, with class II and class III mandibular skeletal malocclusion requiring BSSO, were randomly selected and assigned to each of the study and control groups. A split-mouth study was chosen to conduct this research. Cone beam computed tomography (CBCT) imaging was conducted before the surgery to evaluate the anatomical structure, and three predefined points were marked at the superiormost point of the mandibular foramen, the inferiormost point of the mandibular foramen, and the deepest point of the sigmoid notch. A conventional sagittal split osteotomy was carried out in the control group. Preoperative values were obtained in the study group using the CBCT imaging technique by drawing an imaginary line from the inferiormost part of the mandibular foramen to the line corresponding to the occlusal plane that extended beyond the last molar. The lingual flap reflection was restricted to the internal oblique ridge. The posterior border of the mandible was not reflected. The measurements acquired via CBCT imaging were accurately transferred to the intraoperative surgical site using a vernier caliper. This facilitated the precise completion of the horizontal osteotomy, ascending ramus cuts, and vertical osteotomies. BSSO was performed, the mandibular setback or advancement was done with intermaxillary fixation, and the procedure was completed by rigid fixation. Types of lingual splits, types of lateral bone cut ends (LBCEs), any unfavorable split, and the time taken for the surgery (in minutes) were assessed. The surgery time in the control group (20.1538 ± 2.85325 min) was found to be higher than that in the study group (17.6154 ± 3.59487 min), with a p-value of 0.02. No significant differences were observed when assessing the presence of unfavorable splits in both groups (p = 0.500). Buccal LBCEs were the most prevalent, followed by inferior types. Type I lingual split was the most common in the study group (70%). This technique offers a dependable anatomical reference and significantly reduces surgical time for beginners. Additionally, the patterns of the lingual split were correlated with the types of lateral bone cut ends.

A multifunctional scannable mounting device for computer guided implant surgery: An in vitro study

As part of the growing digitization of the dental field, clinicians are looking for ways to simplify digital workflow, reduce chairside time, and provide new work patterns for future applications. Whether scanning with a multifunctional apparatus (MFA) scan body results in improved scanning is unclear. The purpose of this in vitro study was to compare the horizontal, vertical, and angular deviations with the MFA scan body with a commercially available scan body (SBIO). Sixteen identically printed edentulous maxillary models were used to plan two Ø3.8×11.5-mm implants in the right maxillary first molar and left maxillary central incisor locations. Two implants in each model were installed using a surgical guide. The models were scanned using an intraoral scanner with MFA and then rescanned twice, with SBIO using the intraoral scanner and a laboratory 3D scanner. The implants were digitally positioned according to the scanned MFA and SBIO locations in standard tessellation language (STL) files. These STL files were superimposed on the reference laboratory 3D scanner STL files. Linear measurements included implant apex/cervical horizontal/vertical deviations, as well as implant axis angular deviations. Normality was evaluated with the Shapiro-Wilk test. Paired samples t tests (2 sided) were used for the mean SBIO-MFA deviation difference. To compare the molar/incisor sites, paired samples Wilcoxon tests were used (α=.05 for all tests). No statistically significant differences were found between the MFA/ SBIO deviations, for each of the 10 sites × deviation combinations (P>.05). Overall, the lowest endpoint of the 95% confidence intervals among the 8 linear measurement comparisons was -0.107 mm (coronal vertical deviation, right maxillary first molar site) and -0.30 degrees between the 2 angular measurement comparisons. The current in vitro study demonstrated high accuracy for the novel MFA device, similar to that of the standard SBIO scan body. Furthermore, the current study offers an alternative technique to evaluate the accuracy of implant placement by using scanning and back programming over the traditional postplacement cone beam computed tomography (CBCT) scanning.

Comparing Small Buccal Dehiscence Defects Treated with or without Guided Bone Regeneration. A Sub-Analysis of a RCT.

to assess clinical and radiographical outcomes of single tooth posterior implants with a dehiscence defect treated with or without guided bone regeneration (GBR). In a randomized clinical trial of 59 patients, single-tooth posterior implants were placed. For the subanalysis of 16 patients with a buccal dehiscence defect (≤ 5mm), the implants were randomly assigned to GBR or spontaneous healing (SH). In 8 patients, the implants were surrounded by native bone (Native bone). A transmucosal healing approach was chosen for all sites. Patients were examined at restoration delivery (RD) and at one year (1y). Measurements included: soft tissue thickness (STT), bone tissue thickness (BTT) and buccal contour, based on cone-beam computed tomography (CBCT), optical scans, clinical parameters. All data were analyzed descriptively. The mean STT at implant shoulder (IS) showed a gain of 0.15 mm (Q1: - 0.16, Q3: 0.49) for the GBR group and 0.03 mm (Q1: -0.49, Q3: 0.13) for the SH group. The mean BBT 1 mm below IS showed a loss of 0.25 mm (Q1: -0.85, Q3: -0.09) for the GBR group and 0.04 mm (Q1: -0.14, Q3: 0.17) for the SH group. All peri-implant soft tissue parameters indicated healthy peri-implant tissues with no clinically relevant differences between the groups. Patient-reported outcomes regarding pain one day after surgery were similar among the study groups. The present sub-analysis resulted in a similar buccal contour and similar radiographic outcomes as well as peri-implant health for sites treated with or without GBR.

Three-dimensional Analysis of Skeletal Stability in Cleft Lip and Palate Patients Undergoing Bimaxillary Surgery With Le Fort I Osteotomy and Intraoral Vertical Ramus Osteotomy.

Orthognathic surgery in patients with lip and palate clefts is challenging owing to scar tissue from primary repairs and severe deformities. In this study, we evaluated the stability of Le Fort I osteotomy with intraoral vertical ramus osteotomy (IVRO) in patients with cleft lip and palate using 3-dimensional (3D) analysis. This retrospective study comprised 14 cleft lip and palate patients (3 females, 11 males; the average age at surgery: 23.8y) who underwent bimaxillary orthognathic surgery involving Lefort I osteotomy and IVRO. Cone-beam computed tomography (CBCT) images were obtained at preoperative (T0), 1-month postoperative (T1), and 1-year follow-up (T2) periods. The 3D analysis assessed the transitions and rotations of the maxilla and mandible using a virtual triangle. The maxilla showed stability in all directions at the 1-year follow-up with minimal relapse. The distal segment of the mandible exhibited clinically acceptable anterior (1.15mm relapse) movements and pitch rotation (2.88° counterclockwise relapse) during the first year postoperatively. The proximal mandibular segment underwent anterior-inferior transition (1.21 and 2.01mm, respectively) and lateral-outward rotation (4.90° and 7.51°, respectively) postsurgery, remaining unchanged 1 year postoperation. Le Fort I osteotomy with IVRO provides skeletal stability in patients with cleft lips and palates. This study demonstrated a minimal maxillary relapse and clinically acceptable movements in the distal mandibular segment during the first postoperative year. The proximal mandibular segment moved anteriorly and inferiorly, rotated laterally and outward after surgery, and remained unchanged at the 1-year follow-up.

Comparative evaluation of remaining dentin thickness and root canal transportation in curved canals with newer nickel–titanium single and multiple rotary file systems: A cone-beam computed tomography study

Abstract Context: The purpose of this study was to evaluate and compare the remaining dentin thickness and root canal transportation of WaveOne GOLD, XP-endo Shaper, and GenEndo file systems to assess their performance in curved canals using cone-beam computed tomography (CBCT) imaging. Materials and Methods: Seventy-five extracted maxillary first molars were selected with a curvature ranging between 15° and 30°. The samples were allocated into three groups (n = 25) and shaped using WaveOne GOLD, XP-endo Shaper, and GenEndo files. CBCT images were captured before and after instrumentation. Statistical Analysis: The remaining dentin thickness and root canal transportation were measured at 3, 5, and 7 mm from the apex in both mesiodistal and buccolingual directions. The data were statistically analyzed using one-way ANOVA followed by Tukey’s post hoc test. Results: GenEndo file system demonstrated greater preservation of remaining dentin thickness and resulted in less root canal transportation compared to the WaveOne GOLD and XP-endo Shaper systems across all three levels. Conclusions: GenEndo file system which comprises multiple files has removed less amount of dentin and canal transportation when compared to single file systems, i.e., WaveOne GOLD and XP-endo Shaper file systems.

Assessment of the mandibular incisive and mental canal in dentate and edentulous mandibles using cone-beam computed tomography

ObjectivesThis study evaluated the prevalence, diameter and location of the mandibular incisive canal (MIC) and the transition pattern and anterior loop length (ALL) of the mental canal and compared these values between dentate and edentulous mandibles. MethodsA total of 187 cone-beam computed tomography (CBCT) images of mandibles, namely, 100 images of dentate mandibles and 87 images of edentulous mandibles, were obtained. CBCT data related to the incisive canal and mental canal were analyzed by one examiner. ResultsThe prevalence of the MIC was 75∼78 %, showing no difference based on laterality or the presence of teeth. The ALL significantly differed depending on the presence of teeth as well as sex. The presence of teeth affected the size of the MIC in the female group, and the diameter of the MIC in the edentulous group was significantly narrower than that in the dentate group. The diameter of the MIC was significantly greater in males than in females in the edentulous group. Meanwhile, the location of the MIC in the male group depended on the presence of teeth at each measuring point, and the MIC was significantly closer to the lower border of the mandible in the female group than in the male group at all measuring points except at 0 mm. ConclusionsThis study indicated that the presence of teeth significantly affects the type of transition of the mental canal, the ALL, and the diameter and location of the MIC. Additionally, sex could be a factor affecting MIC location, MIC diameter and anterior loop length.

Adaptive assessment based on fractional CBCT images for cervical cancer.

Anatomical and other changes during radiotherapy will cause inaccuracy of dose distributions, therefore the expectation for online adaptive radiation therapy (ART) is high in effectively reducing uncertainties due to intra-variation. However, ART requires extensive time and effort. This study investigated an adaptive assessment workflow based on fractional cone-beam computed tomography (CBCT) images. Image registration, synthetic CT (sCT) generation, auto-segmentation, and dose calculation were implemented and integrated into ArcherQA Adaptive Check. The rigid registration was based on ITK open source. The deformable image registration (DIR) method was based on a 3D multistage registration network, and the sCT generation method was performed based on a 2D cycle-consistent adversarial network (CycleGAN). The auto-segmentation of organs at risk (OARs) on sCT images was finished by a deep learning-based auto-segmentation software, DeepViewer. The contours of targets were obtained by the structure-guided registration. Finally, the dose calculation was based on a GPU-based Monte Carlo (MC) dose code, ArcherQA. The dice similarity coefficient (DSCs) were over 0.86 for target volumes and over 0.79 for OARs. The gamma pass rate of ArcherQA versus Eclipse treatment planning system was more than 99% at the 2%/2mm criterion with a low-dose threshold of 10%. The time for the whole process was less than 3 min. The dosimetric results of ArcherQA Adaptive Check were consistent with the Ethos scheduled plan, which can effectively identify the fractions that need the implementation of the Ethos adaptive plan. This study integrated AI-based technologies and GPU-based MC technology to evaluate the dose distributions using fractional CBCT images, demonstrating remarkably high efficiency and precision to support future ART processes.

Neurosurgical Risk Assessment of Dental Patients using Conebeam CT

Neurosurgical Risk Assessment of Dental Patients using Conebeam CT

Gel dosimetry: An overview of dosimetry systems and read out methods

Gel dosimetry has emerged over the past three decades in response to a growing need in high-precision radiotherapy to assess, in three dimensions, the absorbed radiation dose, as would be administered in cancer patients. Radiation-induced reaction mechanisms are dependent on the class of gel dosimeter, with four classes emerging as primary dosimeters for use in radiation therapy dose verification: (i) Fricke gel dosimeters contain a Fricke solution consisting of ammonium iron (II) sulfate in an acidic solution of sulfuric acid. In Fricke systems an oxidation of ferrous ions results in a change in the nuclear magnetic resonance (NMR) relaxation rate, which enables reading out Fricke gel dosimeters by use of MRI. The radiation-induced oxidation in Fricke gel dosimeters can also be visualized by adding a redox indicator. (ii) Polymer gel dosimeters exploit the radiation induced polymerization reaction of vinyl monomers and are predominantly read out by quantitative MRI or X-ray CT. (iii) Radiochromic dosimeters do not demonstrate a significant radiation-induced change in NMR properties but can be scanned by use of optical scanners (optical CT). In contrast to Fricke gel dosimeters, radiochromic gel dosimeters do not rely on the oxidation of a metal ion but exhibit a color change upon radiation. (iv) Radiofluorogenic dosimeters become fluorescent when exposed to ionizing radiation and can be read out with a planar scanning light beam. Likewise, the imaging modality used to extract quantitative dose information depends on the class of dosimeter being used, and three primary imaging modalities have emerged in this context: quantitative MRI, x-ray CT, and optical CT imaging. The accuracy and precision of the dose information extracted from gel dosimetry systems depends on both the dosimetric properties of the gel dosimeters and the readout technique, and the optimal readout method depends on the gel dosimeter response. Despite remaining an active field of research and illustrations of the application of gel dosimetry for the validation of clinical dose distributions, the utilizatio of gel dosimetry as a routine clinical dosimeter has been rather limited. However, with the introduction of new radiotherapy techniques that focus on organ motion compensation, new fractionation schemes, and extreme dose rates, the need for 3D radiation dosimetry is apparent. Even with the need for 3D dosimetry being apparent, gel dosimetry faces continued challenges in areas regarding the extraction of reproducible, accurate, and precise dose information. This review paper focuses on an introduction to gel dosimeter classes; a detailed examination of the three readout techniques with emphasis on the achievable accuracy, precision, and optimization of readout parameters; an outlook on future applications in emerging new radiotherapy techniques. We note that the introduction of theragnostic hybrid MRI-Linacs that combine an MRI-scanner and a clinical linear accelerator create new opportunities for inline polymer gel dosimetry. Likewise, the use of cone beam CT on linear accelerators opens up the possibility to read out gel dosimeters on the linac. Multiple optical CT designs have shown that optical CT gel dosimetry is eminently capable of providing high quality dosimetric information from clinically relevant treatment regimes. As a result, gel dosimetry provides exciting opportunities for 3D radiation dosimetry that were not available even a few years ago. The unique feature set of a properly executed gel dosimetry workflow allows for the extraction of dosimetric information, in 3D, that is not possible with any other dosimetry system and hence gel dosimetry provides exciting opportunities for clinical and research work in the area of radiation dose measurement.

EP.07A.25 Portable Cone Beam CT for Intraoperative Marking of Small Pulmonary Nodules; Anywhere, Anytime!

EP.07A.25 Portable Cone Beam CT for Intraoperative Marking of Small Pulmonary Nodules; Anywhere, Anytime!

Setup errors analysis in iterative kV CBCT: A clinical study of cervical cancer treated with Volumetric Modulated Arc Therapy.

This study aims to analyze setup errors in pelvic Volumetric Modulated Arc Therapy (VMAT) for patients with non-surgical primary cervical cancer, utilizing the onboard iterative kV cone beam CT (iCBCT) imaging system on the Varian Halcyon 2.0 ring gantry structure accelerator to enhance radiotherapy precision. We selected 132 cervical cancer patients who underwent VMAT with daily iCBCT imaging guidance. Before each treatment session, a registration method based on the bony structure was employed to acquire iCBCT images with the corresponding planning CT images. Following verification and adjustment of image registration results along the three axes (but not rotational), setup errors in the lateral (X-axis), longitudinal (Y-axis), and vertical (Z-axis) directions were recorded for each patient. Subsequently, we analyzed 3642 iCBCT image setup errors. The mean setup errors for the X, Y, and Z axes were 4.50±3.79mm, 6.08±6.30mm, and 1.48±2.23mm, respectively. Before correction with iCBCT, setup margins based on the Van Herk formula for the X, Y, and Z axes were 6.28, 12.52, and 3.26mm, respectively. In individuals aged 60 years and older, setup errors in the X and Y axes were significantly larger than those in the younger group (p<0.05). Additionally, there is no significant linear correlation between setup errors and treatment fraction numbers. Data analysis underscores the importance of precise Y-axis setup for cervical cancer patients undergoing VMAT. Radiotherapy centers without daily iCBCT should appropriately extend the planning target volume (PTV) along the Y-axis for cervical cancer patients receiving pelvic VMAT. Elderly patients exhibit significantly larger setup errors compared to younger counterparts. In conclusion, iCBCT-guided radiotherapy is recommended for cervical cancer patients undergoing VMAT to improve setup precision.

Braids and beyond: a comprehensive study on pipeline device braid stability from PREMIER data

BackgroundThe pipeline embolization device (PED) has been increasingly used to treat brain aneurysms; however, concerns have been raised about braid stability with newer drawn filled tubing technology devices.ObjectiveTo evaluate braid...

Intraoperative marking of pulmonary nodules in a hybrid operating room: electromagnetic navigation bronchoscopy versus percutaneous marking.

Intraoperative identification of subsolid or small pulmonary nodules during minimally invasive procedures is challenging. Recent localization techniques show varying success and complications. Hybrid operating rooms (HORs), equipped with radiological tools, facilitate intraoperative imaging. This study compares the accuracy and safety of marking pulmonary nodules using electromagnetic navigation bronchoscopy (ENB) combined with Cone Beam Computed Tomography (CBCT) vs. CBCT-guided percutaneous marking (PM). This retrospective cohort study included patients with pulmonary nodules scheduled for minimally invasive resection in a HOR. Marking techniques included ENB assisted by CBCT and PM guided by CBCT. The study compared the success rate, procedure time, intraoperative complications and radiation dose of both techniques. A total of 104 patients with 114 nodules were included (October 2021-July 2024). Thirty nodules were marked using ENB, and 84 with PM. One case used both techniques due to ENB failure. No differences among groups were found in nodule characteristics. Success rates were similar (93.3% in ENB group vs. 91.7% in PM group, p = 1). Marking took significantly longer time in the ENB group (median 40 min) compared to PM group (25 min, p = 0.007). Five (6%) patients in the PM group experienced intraoperative complications compared to none in the ENB (p = 0.323). Radiation dose was significantly higher in the ENB group (p = 0.002). ENB assisted by CBCT is a safe and effective technique, with success rates comparable to CBCT-guided PM, though it may result in longer procedural times and higher radiation doses.

The Sensitivity and Specificity of Susceptibility Weighted Imaging Phase (Swip) in Detecting Intracranial Large Artery Calcium Stenosis Compared to Cone Beam CT

Introduction: Intracranial calcifications are common and often associated with advanced stages of atherosclerosis. Studies estimating the prevalence of intracranial calcifications using other imaging modalities are common, however, studies comparing the diagnostic accuracies of cone-beam computed tomography (CBCT) and susceptibility-weighted imaging (SWI) and generated scoring systems for SWI are not well established. Aims: The objectives of the present study are to identify locations of intracranial calcifications; estimate the sensitivity and specificity rates for each intracranial vessel and each modality; estimate the sensitivity and specificity rates for diagnosing each grade of stenosis for each modality; and generate cutoff value for predicting each grade of intracranial stenosis and for each modality; as well as to develop a scoring system for estimating intracranial stenosis using SWI. Material and Methods: The study employs a prospective cross-sectional study design to collect brain data from 146 stroke patients who had initially undergone CBCT and SWI examinations. Data were collected using pro forma from January 2021 to December 2022 at Hospital Pengajar Universiti Putra Malaysia. Results: The results show an estimated prevalence of intracranial calcification of 87.7% and 92.5% for CBCT and SWI respectively. Regarding intracranial calcium grades, the prevalence of minimum – mild, moderate, and severe grade stenosis were 18.5%, 58,9%, and 10.3% respectively for CBCT and 2.7%, 33.8%, and 57.5% for SWI. Further, the results revealed that CBCT attained a sensitivity of 100% for the anterior cerebral artery, 71% for the middle cerebral artery, and 100% for the vertebral artery as well as a specificity of 90%, 80%, and 42% for the anterior cerebral artery, middle cerebral artery, and vertebral artery respectively. However, with the SWI modality, basilar, vertebral, and middle cerebral arteries reached a sensitivity of 90%, 63%, and 87% and a specificity of 82%, 95%, and 59%. Conclusion: In conclusion, both CBCT and SWI demonstrate reliable means of detecting intracranial calcifications and vessel stenosis with SWI outperforming CBCT.

Cone-beam computed tomography-guided shape-sensing robotic bronchoscopy vs. electromagnetic navigation bronchoscopy for pulmonary nodules.

Electromagnetic navigation bronchoscopy (ENB) and shape-sensing robotic-assisted bronchoscopy (ssRAB) are minimally invasive technologies for the diagnosis of pulmonary nodules. Cone-beam computed tomography (CBCT) has shown to increase diagnostic yield by allowing real-time confirmation of position of lesion and biopsy tool. There is a lack of comparative studies of such platforms using CBCT guidance to overcome computed tomography to body divergence. The aim of this study was to compare the diagnostic yield of ENB- and ssRAB-guided CBCT for biopsy of pulmonary nodules. We conducted a retrospective comparative study of consecutive patients undergoing ENB-CBCT and ssRAB-CBCT. Navigational success was defined as biopsy tool within lesion confirmed during CBCT. Diagnostic yield was assessed using two methods: (I) presence of malignancy or benign histological findings that lead to a specific diagnosis at the time of bronchoscopy, and (II) longitudinal follow-up of patients with nonspecific benign finding during bronchoscopy. ENB-CBCT was used to biopsy 97 nodules and ssRAB-CBCT was used to biopsy 111 nodules. Median size of the lesion for the ENB-CBCT group was 16.5 mm [interquartile range (IQR), 12-22 mm] as compared to 12 mm (IQR, 9-16 mm) in the ssRAB-CBCT group (P<0.001). Navigational success was 70.1% in ENB-CBCT arm as compared to 83% in ssRAB-CBCT arm respectively (P=0.03). Diagnostic yield was 66% for ENB-CBCT and 89.2% for ssRAB-CBCT (P<0.001) following bronchoscopy; 79.4% for ENB-CBCT and 95.4% for ssRAB-CBCT (P<0.001) with longitudinal follow-up data respectively. Following multivariate regression analysis adjusting for the size of the lesion, distance from the pleura, presence of bronchus sign, number of CBCT spins, and number of nodules, the odds ratio for the diagnostic yield was 4.72 [95% confidence interval (CI): 2.05-10.85; P<0.001] in the ssRAB-CBCT group as compared with ENB-CBCT. The overall rate of adverse events was similar in both groups (P=0.77). ssRAB-CBCT showed increased navigational success and diagnostic yield as compared to ENB-CBCT for pulmonary nodule biopsies.

Diagnostic Challenges and Management of Non-Odontogenic Toothache: A Case of Unilateral Pansinusitis Mimicking Dental Pain

This case report details the diagnostic challenge and subsequent management of a 38-year-old male patient who presented with severe, sharp, and non-localized pain in the right maxillary distal area. Initial¬ly unresponsive to non-steroidal anti-inflammatory drugs and antibiotics, the patient’s symptoms deviat¬ed from typical odontogenic pain characteristics. Comprehensive dental examinations revealed minimal pathologies, challenging initial assumptions of dental-origin pain. Advanced diagnostic imaging, including Orthopantomography and Cone Beam Computed Tomography (CBCT), was pivotal in identifying unilat¬eral pansinusitis, with notable obstruction in the maxillary, ethmoid, and frontal sinuses. Further microbi¬ological analysis confirmed a Staphylococcus aureus and anaerobic infection, refocusing the diagnosis to a non-odontogenic source. The patient underwent a targeted 14-day complex antibiotic regimen, supple¬mented with local treatments including Nasonex nasal spray and saline nasal irrigations. This integrative approach resulted in marked symptom improvement and was instrumental in the patient’s recovery. This case highlights the critical need for thorough evaluation in distinguishing between odontogenic and non-od¬ontogenic sources of orofacial pain, ensuring accurate diagnosis and effective treatment.

A Study on the Evaluation of Image-Guided Treatment Use in Radiotherapy Centers in Türkiye

This study presents a preliminary investigation into the use of image-guided radiation therapy (IGRT) in radiotherapy centers in Türkiye, based on survey data. Radiation therapy technologists were administered a 67-item Internet-based questionnaire. The first five items focused on demographic data, while the remaining items pertained to IGRT applications in the clinics where the technicians worked. Statistical data of the answers obtained were used in SPSS 28.0. While evaluating the study data, descriptive statistical methods (frequency, percentage) were used. A total of 314 individuals participated in the survey, with 45.9% (n=144) being female and 54.1% (n=170) being male. The study focused on patients with stomach (20.6%), rectum (18.9%), prostate (17.6%), head and neck (14.5%), lung (14.3%), and breast (13.9%) cancers. It was observed that megavoltage (MV) ports (35.7%) were used more frequently during daily checks. It has been stated that 1-25 MV ports are drawn daily. This is followed by Cone Beam Computer Tomography (CBCT) and kilovoltage (kV) port checks. In our country, it is seen that important steps have been taken in IGRT and its use is quite common. It has been observed that the technical infrastructure and manpower in the clinics are sufficient. It is predicted that the development of systems that reduce the doses received by patients and employees with IGRT and the development of wage policies will increase the use of IGRT. We hope that this result will be supported by future large-scale studies. Although we think that the use of IGRT is at an adequate level, there are differences in practices between clinics. It is thought that the establishment of national protocols for the use of IGRT will be in favour of patients and technicians.

The impact of collagen membrane fixation protocols on volume stability in horizontal ridge augmentation in the aesthetic area: A retrospective study.

This study aimed to evaluate the impact of different collagen membran fixation protocols on the volume stability in horizontal ridge augmentation in the aesthetic area. A total of 48 patients with 65 augmented sites were included in this study. Implants were placed in the aesthetic region, and simultaneous guided bone regeneration (GBR) surgery was performed for horizontal ridge augmentation. Participants were divided into four groups, each comprising 12 patients, based on different absorbable collagen membrane fixation protocols. Group 1: without fixation; Group 2: fixation with absorbable sutures; Group 3: fixation with titanium pins; Group 4: fixation with titanium pins and absorbable sutures. Cone beam computed tomography (CBCT) was performed immediately after surgery and at 6 months post-surgery, respectively. The horizontal thickness of the augmented region was analyzed for volume stability at the implant shoulder (H0) and 1-5 mm apical to the implant shoulder (H1-H5). Changes in labial thickness during bone healing were calculated as absolute values (mm) and relative values (%). After 6 months of bone healing, horizontal thickness was significantly reduced at all levels (H0-H5) in all groups compared to immediate post-surgery results (p < 0.05). At H1-H5, horizontal bone loss in group 1 was significantly higher than in the other three groups (p < 0.05). Group 4 exhibited significantly less horizontal bone loss compared to group 2 at H0-H2 (p < 0.05) and group 4 compared to group 3 at H0-H1 (p < 0.05). No significant difference in horizontal bone loss between groups 2 and 3 was detected at H0-H5 (p > 0.05). Guided bone regeneration in the aesthetic area with additional membrane fixation demonstrated superior volume stability of the augmented region compared to cases without fixation. There was no significant difference in bone volume stability between membrane fixation with titanium pins and fixation with absorbable sutures. However, the combined use of pins and absorbable sutures yielded superior volume stability.

Accuracy of Mandibular Foramen Localization Using Digital Orthopantomogram (OPG) in Middle Eastern Population.

Locating the mandibular foramen (MF) through imaging is clinically important for inferior alveolar nerve (IAN) anesthesia and mandibular ramus osteotomies. Although cone-beam computed tomography (CBCT) is superior in imaging the mandible, an orthopantomogram (OPG) is preferred for its ease of use and availability. Therefore, the present study aimed to evaluate the accuracy of digital OPG in localizing the MF, in a subset of the Middle Eastern population. Radiographic images (OPG and CBCT) of selected patients (adults, dentulous and no mandibular abnormalities) were used to locate the MF through digital measurements (mm) of the anteroposterior distance from the anterior border of the ramus (MF-AP) and the superoinferior position from the mandibular occlusal plane (MF-SI). Measurements were statistically compared between OPG and CBCT for accuracy. Differences in measurements between OPG and CBCT were compared against the anatomic location (right/left), age and biological sex, assuming a p-value < 0.05 as significant. A total of 204 radiographic records (males: 100/females: 104/mean age: 34.65 ± 11.55 years) were evaluated. The measurements for the MF were MF-AP-OPG (right: 13.53 ± 2.44/left: 13.19 ± 2.25), MF-AP-CBCT (right: 13.61 ± 2.39/left: 13.36 ± 2.19), MF-SI-OPG (right: 5.25 ± 1.71/left: 5.41 ± 1.65) and MF-SI-CBCT (right: 5.59 ± 1.66/left: 5.52 ± 1.61). Measurements between OPG and CBCT were not significantly different, except for MF-SI (right) (p = 0.042). While the overall difference between OPG and CBCT (MF-AP/MF-SI) measurements showed a significant association (p < 0.01) with the anatomic location (right/left), a significant association (p < 0.05) with biological sex was observed only for MF-AP. Based on this study's outcomes, digital OPG is an accurate modality to locate the MF based on anteroposterior (MF-AP) and superoinferior (MF-SI) measurements. This would be clinically beneficial for dental and oral surgeons to achieve the optimum IAN block anesthesia based on preoperative panoramic radiographs. Similarly, it would assist maxillofacial surgeons in planning mandibular orthognathic surgeries and ramus osteotomies without complications.

Characteristics of the Occlusal Plane Associated with Unilateral and Bilateral Articular Eminence Inclination: A Cross-Sectional CBCT Study.

The characteristics of the temporomandibular joint (TMJ) are essential in orthodontic and prosthetic treatments. Previous studies have suggested an association between articular eminence inclinations (AEI) and occlusal plane characteristics using radiographs, but no bilateral analysis has been conducted using cone beam computed tomography (CBCT). Objective: This study aimed to investigate the specific characteristics of the occlusal plane inclinations associated with unilateral and bilateral AEI using CBCT. Methods: We conducted a cross-sectional study to evaluate 200 temporomandibular joints (TMJs) from 100 records obtained at the orthodontic department. We evaluated the association between the AEI, and occlusal plane characteristics like the cant of the occlusal angle, occlusal plane angles, inclination of the upper incisor to the Frankfort plane and palatal plane using both bivariate and multivariate analyses both unilaterally and bilaterally. Results: Our findings suggested statistically significant associations (p < 0.050) between AEI (bilateral) and occlusal inclination parameters, including the cant of the occlusal plane (Coef. -0.38; 95%CI -0.70:-0.06; p = 0.017), occlusal plane angle (Coef. -0.39; 95%CI -0.740:-0.05; p = 0.024), and position of the upper incisor relative to the palatal plane (Coef. -0.34; 95%CI -0.63:-0.06; p = 0.016). Conclusion: This study suggests an association between dental inclinations and AEI, which reflects the anatomical characteristics of TMJ and its related dental structures.