Nomogram to predict radicular grooves in maxillary lateral incisors in preoperative orthodontic population.

OBJECTIVES: This study aimed to develop and validate a predictive nomogram for diagnosing radicular grooves (RG) in maxillary lateral incisors (MLIs), integrating demographic information, anatomical measurements, and Cone Beam Computed Tomography (CBCT) data to diagnose the RG in MLIs based on the clinical observation before resorting to the CBCT scan. MATERIALS AND METHODS: A retrospective cohort of orthodontic patients from the School and Hospital of Stomatology, Wuhan University, was analyzed, including demographic characteristics, photographic anatomical assessments, and CBCT diagnoses. The cohort was divided into development and validation groups. Univariate and multivariate logistic regression analyses identified significant predictors of RG, which informed the development of a nomogram. This nomogram's performance was validated using receiver operating characteristic analysis. RESULTS: The study included 381 patients (64.3% female) and evaluated 760 MLIs, with RG present in 26.25% of MLIs. The nomogram incorporated four significant anatomical predictors of RG presence, demonstrating substantial predictive efficacy with an area under the curve of 0.75 in the development cohort and 0.71 in the validation cohort. CONCLUSIONS: A nomogram for the diagnosis of RG in MLIs was successfully developed. This tool offers a practical checklist of anatomical predictors to improve the diagnostic process in clinical practice. CLINICAL RELEVANCE: The developed nomogram provides a novel, evidence-based tool to enhance the detection and treatment planning of MLIs with RG in diagnostic and therapeutic strategies.

The Assessment of C-shaped Canal Prevalence in Mandibular Second Molars Using Endodontic Microscopy and Cone Beam Computed Tomography: An In Vivo Investigation.

Background Understanding root canal anatomy variations, particularly C-shaped canals, is crucial for successful endodontic treatment. This study used clinical and radiographic methods to assess the prevalence and characteristics of C-shaped canals in mandibular second molars in Western Maharashtra. Materials and methods This prospective study was conducted in the western region of Maharashtra, India. The samples included patients requiring endodontic treatment for mandibular second molars. Clinical evaluation was conducted using a surgical endodontic microscope and cone beam computed tomography (CBCT) imaging. Inclusion and exclusion criteria ensured the selection of a focused and homogeneous sample. Data analysis included assessment of unilateral/bilateral occurrence, canal distribution, and cross-sectional characteristics. Results Out of 200 mandibular second molars, 7.5% exhibited C-shaped root canals, with no significant gender differences. Canal distribution varied across coronal, middle, and apical levels, with prevalent configurations being C1, C2, C3, and C4. No significant differences were observed in canal distribution based on root levels. No significant gender differences were found in the presence of grooves on the root surfaces. Conclusion This study provides valuable insights into the prevalence and characteristics of C-shaped canals in mandibular second molars in Western Maharashtra. Further research into histological and genetic aspects can enhance our understanding, leading to improved treatment strategies for complex root canal anatomy variations.

A Rare Case of Single-Rooted Maxillary First Molar With Type II Canal Configuration.

The morphological variations in roots and root canals vary greatly in multi-rooted teeth making it a challenge for accurate diagnosis and effective endodontic therapy. In addition to using technology appropriately, this article highlights how important it is to have a complete understanding of root canal morphology. With the assistance of cone-beam computed tomography (CBCT) images and a dental operating microscope (DOM), successful endodontic treatment was performed on a single-rooted maxillary first molar with Vertucci's type II canal configuration. CBCT and DOM proved to be valuable tools for the effective diagnosis and management of this atypical morphology.

Mandibular advancement device in obstructive sleep apnea treatment: what happens to the condyle position and patient response?

BACKGROUND: This study aims primarily to assess the mandibular condyles and patient response to MAD therapy using cone-beam computed tomography (CBCT). Also, the study proposes to analyze whether variations in condylar position, OSA severity and mandibular protrusion influence patient response. METHODS: 23 patients diagnosed with mild/moderate OSA and treated with MAD comprised the sample. Clinical, CBCT, and PSG assessments were conducted at baseline and with MAD in therapeutic protrusion (4-6 months of MAD use). The condyle position was vertically and horizontally evaluated at baseline and at the therapeutic protrusion. RESULTS: The condyle position significantly changed with MAD, showing anterior (7.3 ± 2.8 mm; p < 0.001) and inferior (3.5 ± 1 mm; p < 0.001) displacement. Patients with mild OSA required more protrusion (p = 0.02) for improvement. Responders exhibited a significantly prominent (p = 0.04) anterior baseline condyle position. A negative modest correlation was found between treatment response and baseline condyle anterior position (p = 0.03; r=-0.4), as well as between OSA severity and the percentage of maximum protrusion needed for therapeutic protrusion (p = 0.02; r=-0.4). The patient protrusion amount did not predict condylar positional changes. Neither condyle position, OSA severity, nor therapeutic protrusion were predictors of MAD treatment response. CONCLUSION: MAD resulted in anterior and inferior condylar displacement, and the amount of protrusion did not predict condylar positional changes. Responders showed a more anterior baseline condyle position. OSA severity and mandibular protrusion did not predict treatment response.

The added value of a new high-performance ring-gantry CBCT imaging system for prostate cancer patients.

BACKGROUND AND PURPOSE: A novel Cone-Beam Computed Tomography (CBCT) named HyperSight provides superior CBCT image quality compared to conventional ring gantry CBCT imaging, and it is suitable for dose calculations for prostate cancer, but it comes with considerable additional costs. The aim of this study was to determine the added value of HyperSight CBCT imaging compared to conventional CBCT imaging in terms of organ visibility in the male pelvic region. MATERIALS AND METHODS: Twenty prostate cancer patients were included in this prospective clinical study. For each patient three CBCT pairs, consisting of HyperSight and conventional CBCT scans acquired on consecutive days, were included. CBCT scans were evaluated by four observers in terms of visibility of the prostate, bladder, rectum and seminal vesicles. Visibility was scored on a 1-to-5 scale and by annotating axial slices where the organs were hard to delineate. Lastly, observers indicated whether the CBCT scans were of sufficient quality for an online adaptive radiation therapy workflow. RESULTS: All four organs were better visible on HyperSight CBCT scans compared to conventional CBCT scans. The mean visibility scores increased from 3.1 to 4.5 on a 1--5 scale of and the mean number of annotated slices reduced from 4.5 to 1.1. 99% Of the HyperSight CBCT scans were considered suitable for an online adaptive workflow vs 25-83% for the conventional CBCT scans. CONCLUSION: HyperSight CBCT scans yielded a visibility of prostate, bladder, rectum and seminal vesicles comparable to planning CT scans and, ccan replace a repeat planning CT scan in case of anatomical changes requiring a new treatment plan.

A Three-Dimensional Assessment of a Type I Shallow Palatogingival Groove by Cone Beam Computed Tomography: A Case Report.

The palatogingival groove is a developmental anomaly on the palatal surface of the maxillary anterior teeth. The shallow groove, often less than 1 mm, is challenging to diagnose, particularly in radiographic examinations. Such grooves are mistaken for root fractures. In this case study, we explore the prevalence, types, radiological appearances, and treatment options of type I shallow palatogingival grooves encountered in cone beam computed tomography.

A comparative radiographic study of bone density changes around titanium implants in the posterior mandible, preoperative, and postoperative.

Background: Implant success and the state of the surrounding bone require multiple measures, especially in humans, and this study aimed to identify the development of the state of the latter by means of radiographic examination performed during the period of osseointegration as well as investigate the changes in bone density that occur after implant installation and 2 months after functional loading. Implant success rates are affected by bone density at the implant site. Therefore, understanding changes in bone density after dental implant placement is essential, as it correlates with subsequent implant success. Materials and methods: Digital radiographs of 28 implants were taken and evaluated at four intervals: preoperatively, 1 and 3 months postoperatively, and 2 months following placement of the permanent prosthesis. Gray values were measured in different areas around the implants through analyzing X-ray images and measuring bone density around the implants using EzDent - 2D software. The aim of this study was to investigate changes in bone density around implants in three regions: apex, neck, and body, as well as to record average density values during the observation period by measuring digital image gray levels (the gray values of the digital radiographs). This was conducted to determine local bone densities in dental implant recipient sites and to study changes in local bone densities at different intervals, preoperatively and postoperatively and after placement of the prosthesis. Results: A decrease was observed in gray values proportional to reference values 1-month after implant insertion, but these increased at 3 months after insertion and continued to rise 2 months after placement of the prosthesis in the apical, body, and neck regions of the implant. Conclusion: Sensor-tuned radiography can be used as an effective method to support clinical follow-ups as well as measure changes in bone densities around implants in critical cases.

Adolescents and Children Age Estimation Using Machine Learning Based on Pulp and Tooth Volumes on CBCT Images.

OBJECTIVES: To estimate adolescents and children age using stepwise regression and machine learning methods based on the pulp and tooth volumes of the left maxillary central incisor and cuspid on cone beam computed tomography (CBCT) images, and to compare and analyze the estimation results. METHODS: A total of 498 Shanghai Han adolescents and children CBCT images of the oral and maxillofacial regions were collected. The pulp and tooth volumes of the left maxillary central incisor and cuspid were measured and calculated. Three machine learning algorithms (K-nearest neighbor, ridge regression, and decision tree) and stepwise regression were used to establish four age estimation models. The coefficient of determination, mean error, root mean square error, mean square error and mean absolute error were computed and compared. A correlation heatmap was drawn to visualize and the monotonic relationship between parameters was visually analyzed. RESULTS: The K-nearest neighbor model (R2=0.779) and the ridge regression model (R2=0.729) outperformed stepwise regression (R2=0.617), while the decision tree model (R2=0.494) showed poor fitting. The correlation heatmap demonstrated a monotonically negative correlation between age and the parameters including pulp volume, the ratio of pulp volume to hard tissue volume, and the ratio of pulp volume to tooth volume. CONCLUSIONS: Pulp volume and pulp volume proportion are closely related to age. The application of CBCT-based machine learning methods can provide more accurate age estimation results, which lays a foundation for further CBCT-based deep learning dental age estimation research.

Osteosarcoma associated with cemento-osseous dysplasia: co-incidence or two related entities?

BACKGROUND: Osteosarcoma of the jaws is a rare primary malignant tumor of bone. The clinical, radiological and histopathological features of a case associated with cemento-osseous dysplasia is presented. CASE REPORT: A 57-year-old mixed-race female presented with a large, progressive, swelling of the right mandible. Radiographic examination revealed two associated lesions. Partially defined irregular radiopacities were noted in the left mandible, extending from the premolar to the molar region. The lesion had a cotton-wool appearance and resembled a fibro-osseous lesion; i.e. cemento-osseous dysplasia. A second large, expansive and irregular, radiopaque lesion was noted on the right angle of the mandible, extending beyond the inferior cortex of the mandible. The internal structure was heterogeneous and resembled irregular bone formation. The classic "sunburst" appearance of radiating bony spicules can be seen in the posterior-anterior view and the CBCT 3D reconstruction, indicating the outgrowth of the tumor matrix. Histopathological exam confirmed a final diagnosis of osteosarcoma closely associated with cemento-osseous dysplasia. The patient underwent a fludeoxyglucose-18 (FDG) positron emission tomography (PET) scan which indicated metastasis in the left lung and increased uptake in the right mandible. Chemotherapy was initially administered with a plan to resect the tumor, however, the patient demised as a result of medical complications. CONCLUSION: The question in the literature remains whether these two entities are coincidentally found or arise from each other. Nevertheless, it is important for clinicians to closely monitor patients with cemento-osseous dysplasia and biopsy any suspicious lesions that may develop into osteosarcoma.

Breaking New Ground in Interventional Pulmonology: Integrating Cone Beam CT and Robotic-Assisted Bronchoscopy for High-Risk Pneumothorax in Peripherally Located Solitary Pulmonary Nodules.

Lung cancer, a leading cause of global cancer-related deaths, necessitates the development of innovative diagnostic techniques. Traditional bronchoscopy, while useful, has limitations in diagnosing peripheral pulmonary lesions (PPLs) and carries a higher risk of complications such as pneumothorax. However, the field of interventional pulmonology has seen significant advancements, including the introduction of robotic-assisted bronchoscopy (RAB), cone-beam computed tomography (CBCT), radial endobronchial ultrasound (R-EBUS), and rapid on-site evaluation (ROSE). These advancements have greatly improved the precision of diagnosing high-risk PPLs. This report presents the case of a 60-year-old female smoker with chronic obstructive pulmonary disease and extensive centrilobular emphysema, who had a peripherally located high-risk pulmonary nodule. She was successfully diagnosed with metastatic adenocarcinoma using an integrated approach, despite the challenging location of the lesion and high risk of pneumothorax. The integration of RAB with CBCT and augmented fluoroscopy offers a groundbreaking approach for diagnosing and managing difficult-to-reach, high-risk pulmonary nodules, marking a significant stride in the field of interventional pulmonology.

Utilization of a 3D-Printed Mandibular Jaw for Ridge Reconstruction in Periodontics: A Case Report.

Three-dimensional (3D) printing is an emerging manufacturing technology in dentistry with a range of applications. Digital dentistry presented in cone beam CT scan radiographs is a revolution that improved surgical outcomes by optimizing accurate diagnosis and analysis of the surgical sites before surgery. A periodontist can modify the treatment plan, surgical techniques, and incision design based on bone defects seen on cone beam CT scans. Block grafting has been a technique of choice when wound stability is required for guided bone regeneration. There was no significant difference between the different surgical procedures for reconstruction and choice should be given to the simpler and less invasive procedure. A xenograft or allograft block can work as an alternative to the autogenous bone block to reduce the surgery time and patient morbidity. Preparation and shaping of block graft during surgery time to match the defect shape can prolong the operative time, reduce the treatment success, and increase postoperative complications. In this case report, a sterilized 3D-printed mandibular jaw was utilized to visualize the defect size and shape. A bovine xenograft block was then prepared, shaped, and adapted on the 3D-printed jaw 30 minutes before the surgery. The block graft was then transferred and well-fitted on the surgical defect. Handling experience was greater and surgery time and postoperative pain were reduced.

Corrigendum: Anatomical variations of the atlas arches: prevalence assessment, systematic review and proposition for an updated classification system.

[This corrects the article DOI: 10.3389/fnins.2024.1348066.].

Morphological evaluation of the nasopalatine canal using cone beam computed tomography and its clinical implications for orthodontic miniscrew insertion.

BACKGROUND: The morphology of the nasopalatine canal is crucial in the planning of prosthetic restorations in the anterior region of the maxilla, as well as in the placement of orthodontic mini-implants. OBJECTIVES: The aim of this study was to assess the morphology of the nasopalatine canal using cone beam computed tomography (CBCT) scans of patients from the University Dental Clinic in Krakow, Poland, to define the position of the canal in relation to common sites of palatal median microimplant placement, and to investigate potential correlations between the anatomy of the canal and age and gender of the patients. MATERIAL AND METHODS: A total of 120 CBCT images were used to assess the anatomy of the nasopalatine canal in 3 planes of space. The bone thickness anterior to the nasopalatine canal and the distance between the distal margin of Stenson's foramen and the predicted midpalatal microimplant position were also measured. RESULTS: The most frequently observed canal type in the coronal plane was the Y-shaped canal, which was present in 60.8% of patients. The nasopalatine canal was classified as cone-shaped in 31.7% of the scans, cylindrical in 28.3%, hourglass-shaped in 27.5%, and banana-shaped in 12.5%. The mean length of the nasopalatine canal was 11.58 mm. The mean width of the canal was 2.89 mm at the nasal fossa level, 1.94 mm in the middle, and 5.09 mm at the palatal level. The mean bone thickness anterior to the nasopalatine canal was 9.07 mm at the level of the nasal opening, 6.84 mm at the level of the oral opening, and 7.32 mm in the middle. The mean distance between the distal margin of Stenson's foramen and the predicted midpalatal microimplant position varied from 0 to 11.94 mm, with a mean of 2.49 mm. CONCLUSIONS: Given the variety of nasopalatine canal forms and dimensions, detailed analysis of CBCT scans is essential prior to the placement of implants and microimplants.

Recommendation for reducing the crystalline lens exposure dose by reducing imaging field width in cone-beam computed tomography for image-guided radiation therapy: an anthropomorphic phantom study.

In cone-beam computed tomography (CBCT) for image-guided radiation therapy (IGRT) of the head, we evaluated the exposure dose reduction effect to the crystalline lens and position-matching accuracy by narrowing one side (X2) of the X-ray aperture (blade) in the X-direction. We defined the ocular surface dose of the head phantom as the crystalline lens exposure dose and measured using a radiophotoluminescence dosimeter (RPLD, GD-352 M) in the preset field (13.6 cm) and in each of the fields when blade X2 aperture was reduced in 0.5 cm increments from 10.0 to 5.0 cm. Auto-bone matching was performed on CBCT images acquired five times with blade X2 aperture set to 13.6 cm and 5.0 cm at each position when the head phantom was moved from - 5.0 to + 5.0 mm in 1.0 mm increment. The maximum reduction rate in the crystalline lens exposure dose was - 38.7% for the right lens and - 13.2% for the left lens when blade X2 aperture was 5.0 cm. The maximum difference in the amount of position correction between blade X2 aperture of 13.6 cm and 5.0 cm was 1 mm, and the accuracy of auto-bone matching was similar. In CBCT of the head, reduced blade X2 aperture is a useful technique for reducing the crystalline lens exposure dose while ensuring the accuracy of position matching.

Evaluating the Role of AI in Predicting the Success of Dental Implants Based on Preoperative CBCT Images: A Randomized Controlled Trial.

Background: Dental implant surgery has become a widely accepted method for replacing missing teeth. However, the success of dental implant procedures can be influenced by various factors, including the quality of preoperative planning and assessment. Cone beam computed tomography (CBCT) imaging provides valuable insights into a patient's oral anatomy, but accurately predicting implant success remains a challenge. Materials and Methods: In this randomized controlled trial (RCT), a cohort of 150 patients requiring dental implants was randomly divided into two groups: an artificial intelligence (AI)-assisted group and a traditional assessment group. Preoperative CBCT images of all patients were acquired and processed. The AI-assisted group utilized a machine learning model trained on historical data to assess implant success probability based on CBCT images, while the traditional assessment group relied on conventional methods and clinician expertise. Key parameters such as bone density, bone quality, and anatomical features were considered in the AI model. Results: After the completion of the study, the AI-assisted group demonstrated a significantly higher implant success rate, with 92% of implants successfully integrating into the bone compared to 78% in the traditional assessment group. The AI model showed an accuracy of 87% in predicting implant success, whereas traditional assessment methods achieved an accuracy of 71%. Additionally, the AI-assisted group had a lower rate of complications and required fewer postoperative interventions compared to the traditional assessment group. Conclusion: The AI-assisted approach significantly improved implant success rates and reduced complications, underscoring the importance of incorporating AI into the dental implant planning process.

Periapical Cemento-Osseous Dysplasia: A Journey from Diagnostic Dilemma to Accurate Diagnosis with Use of 3D Imaging.

Cemento-osseous dysplasia is a subgroup of fibro-osseous dysplasia commonly invading the tooth-bearing regions of the mandible quite often. These bony pathologies are asymptomatic and are seen on radiographs as an incidental finding. Accurate diagnosis of periapical cemento-osseous dysplasia is very crucial as it will help in the proper management of the patient as the incorrect diagnosis can lead to the unnecessary endodontic treatment of the concerned teeth as it may be misdiagnosed as a periapical pathology. We describe a case of periapical cemento-osseous dysplasia in which a 52-year-old woman had been experiencing discomfort in the right mental area of her mandible for the previous 6 months and had finally sought help at the outpatient department. This case study aims to highlight the significance of making an accurate diagnosis of cemento-osseous dysplasias in the tooth-bearing area.

Assessing the Accuracy and Reliability of Cone-Beam Computed Tomography (CBCT) in Diagnosing Grade II and III Furcation Involvement Compared to Traditional Clinical Examination Methods.

Introduction Chronic periodontal diseases can lead to bone defects and tooth loss, making accurate diagnosis essential for treatment. Various methods are used for diagnosing furcation involvement, with clinical examination and cone-beam computed tomography (CBCT) being the most effective. CBCT produces reliable images with submillimeter resolution, revealing marginal bone contours and furcation defects. Limited studies show that CBCT is more precise than clinical detection for diagnosing furcation involvement. Therefore, CBCT technology can be considered as an adjunct method for furcation involvement detection. This study tests the accuracy and efficiency of CBCT and clinical examination in detecting furcation involvement. Material and methods The study included 25 patients (68 molars) with generalized periodontitis of stage II to IV, Grade B and C. Inclusion criteria required at least two intrabony defects with probing depth > 6mm in both jaws and criteria of periodontitis in at least 30% of the teeth present. Results The study compared clinical examination and CBCT readings for measuring maxillary and mandibular teeth furcation involvement. The results show significant differences between clinical and CBCT measurements of maxillary teeth furcation involvement, particularly in specific areas and types of furcation involvement. In contrast, there were significant differences between clinical and CBCT readings for only a few measurements of mandibular teeth furcation involvement. Therefore, the study suggests that CBCT imaging may be beneficial for accurate diagnosis and treatment planning in cases of furcation involvement in maxillary teeth. Conclusion CBCT imaging is a reliable adjunct method for detecting furcation involvement in maxillary teeth, while clinical examination alone may not be sufficient. Therefore, the use of CBCT technology should be considered in cases where accurate detection of furcation involvement is necessary for successful treatment outcomes. However, further studies with larger sample sizes are needed to confirm these findings.

Comparative Analysis of the Efficacy of Various Retreatment File Systems in the Removal of Gutta-Percha in Retreatment Cases and Time Taken During the Procedure: An In Vitro Cone Beam CT Study.

Background Removing gutta-percha manually can be a challenging task, especially when addressing densely packed root-filling material, particularly in cases where resin-based sealers are employed for obturation. The use of nickel-titanium (NiTi) rotary instruments not only effectively shapes the root canal but also efficiently removes the endodontic filling from the curved canal during retreatment. Hence, incorporating rotary NiTi instruments in retreatment cases can alleviate fatigue for both patients and operators. Objectives This study aims to compare the efficacy of Neo-Endo retreatment files, R-Endo retreatment files, and K and H files in the removal of endodontic filling material. Additionally, the remnants of gutta-percha in root canals are evaluated using cone beam computed tomography (CBCT). Materials and methods A total of 60 extracted first maxillary molar teeth were selected for this study. Canal preparation was conducted using the step-back method up to an apical size of 40 K-file. The obturation process involved the use of gutta-percha points and AH Plus sealer in a lateral compaction technique. Post-operative CBCT scans were taken. The samples were randomly divided according to the retreatment files used: group I included Neo-Endo retreatment files, group II included R-Endo retreatment files, and group III included conventional K-files and Hedstroem files (H-Files). The retreatment procedure was considered complete when the last instrument easily reached the working-length range and was physically clean. A stopwatch was used to record the time taken by each file to remove the obturating material. T1 represented the total time (including irrigation and change of file) required to reach the apex, while T2 indicated the complete removal of materials from the canal with the last instrument. The overall time recorded (TT) was calculated as T1 + T2. The removal process was analyzed with CBCT scans. Results The Neo-Endo retreatment files removed the filling materials better and more quickly than the other files. Conclusions Despite the presence of residual filling material in all samples, the Neo-Endo retreatment files left the least amount of residual filling material and achieved the shortest completion time.

Basal and dentoalveolar transverse parameters in different sagittal and vertical malocclusions in adults: a comparative study.

OBJECTIVE: This study sought to three-dimensionally (3D) evaluate the maxillomandibular basal bone and dentoalveolar widths using cone-beam computed tomography (CBCT) scans in adult Chinese populations with different vertical and sagittal facial skeletal patterns whilst no apparent posterior dental crossbite. MATERIALS AND METHODS: The retrospective cross-sectional comparative study enrolled CBCT images of 259 adult patients (125 males and 134 females). The subjects were divided into the hyperdivergent(n = 82), hypodivergent(n = 88), and normodivergent(n = 89) groups based on the Jarabak ratio (S-GO/N-Me), which were further divided into three subgroups of skeletal Class I, II and III, based on both the ANB angle and AF-BF parameters. ANOVA was used to analyze the extracted data of the studied groups. The intra- and inter-observer reliability was analyzed using the intra-class correlation coefficient (ICC). RESULTS: In all three vertical facial skeletal patterns, the skeletal Class II had significantly smaller mandibular basal bone width compared to skeletal Class I and Class III, both at the first molar and first premolar levels. The skeletal Class III seemed to have smaller maxillary basal bone width compared to skeletal Class I and Class II malocclusions; however, a significant difference was found only in the normodivergent pattern. As for the dentoalveolar compensation, it was most notable that in the hypodivergent growth pattern, the skeletal Class II had significantly smaller maxillary dentoalveolar width compared to the Class I and Class III groups, both at the first molar and first premolar levels. CONCLUSIONS: Based on the sample in the present study, skeletal Class II has the narrowest mandibular basal bone regardless of the vertical facial skeletal pattern. CLINICAL RELEVANCE: For Chinese adults with no apparent transverse discrepancy, the maxillomandibular basal bone and dentoalveolar widths are revealed in specific categories based on different vertical and sagittal facial skeletal patterns. In diagnosis and treatment planning, particular attention should be paid to skeletal Class II for possibly existing mandibular narrowing.

Anatomical variations of the atlas arches: prevalence assessment, systematic review and proposition for an updated classification system.

Objective and background: This study focuses on the atlas, a pivotal component of the craniovertebral junction, bridging the cranium and spinal column. Notably, variations in its arches are documented globally, necessitating a thorough assessment and categorization due to their significant implications in clinical, diagnostic, functional, and therapeutic contexts. The primary objective is to ascertain the frequency of these anatomical deviations in the atlas arches among a Colombian cohort using cone-beam computed tomography (CBCT). Methodology: Employing a descriptive, cross-sectional approach, this research scrutinizes the structural intricacies of the atlas arches in CBCT scans. Analytical parameters included sex distribution and the nature of anatomical deviations as per Currarino's classification. Statistical analyses were conducted to identify significant differences, including descriptive statistics and Chi-square tests. A systematic review of the literature was conducted in order to enhance the current Currarino's classification. Results: The study examined 839 CBCT images, with a nearly equal sex distribution (49.7% female, 50.3% male). Anatomical variations were identified in 26 instances (3%), displaying a higher incidence in females (X2 [(1, N = 839) = 4.0933, p = 0.0430]). The most prevalent variation was Type A (2.5%), followed by Type B (0.4%), and Type G (0.2%) without documenting any other variation. The systematic review yielded 7 studies. A novel classification system for these variations is proposed, considering global prevalence data in the cervical region. Conclusion: The study highlights a statistically significant predominance of Type A variations in the female subset. Given the critical nature of the craniovertebral junction and supporting evidence, it recommends an amendment to Currarino's classification to better reflect these clinical observations. A thorough study of anatomical variations of the upper cervical spine is relevant as they can impact important functional aspects such as mobility as well as stability. Considering the intricate anatomy of this area and the pivotal function of the atlas, accurately categorizing the variations of its arches is crucial for clinical practice. This classification aids in diagnosis, surgical planning, preventing iatrogenic incidents, and designing rehabilitation strategies.