Sexual dimorphism in the mandible in a Portugese population - Predicting the gender for forensic purpose: a pilot study / Dimorfismo sexual mandibular da população Portuguesa ­ Predição do gênero para análise forense: um estudo piloto

Este estudo teve como objetivo avaliar o dimorfismo sexual em uma coleção de mandíbulas portuguesas através de uma metodologia métrica digital, utilizando análise estatística descritiva, inferencial e multivariada para identificar quais parâmetros são mais dimórficos e quais são os melhores preditores de sexo. Trinta e três mandíbulas (14 mulheres e 19 homens) e pertences pessoais foram fotograficamente registrados com código e sexo. Os dados foram coletados por tomografia e as medidas foram feitas pelo software Simplant Pro. Foram registrados a largura máxima e mínima do ramo mandibular, altura condilar, altura do processo coronoide, altura da sínfise mandibular, ângulo mandibular, distâncias bimentual, biantegonial, bigonial e bicondilar e comprimento máximo mandibular. A análise estatística foi realizada utilizando IBM® SPSS. Os resultados mostraram diferenças estatisticamente significativas para os seguintes parâmetros: altura do processo coronoide, altura do côndilo, comprimento máximo da mandíbula e largura mínima do ramo mandibular. Na análise estatística multivariada foi possível identificar a altura do processo coronoide como melhor preditor de sexo com precisão em 72,2% dos casos. Isto permite uma diferenciação mais fácil entre mandíbulas femininas e masculinas com uma precisão de 64,3% e 78,9%, respectivamente. Foi possível concluir que a altura do processo coronoide é o parâmetro mais dimórfico e o melhor preditor de sexo na amostra.

This study aimed to assess sex dimorphism in a collection of Portuguese mandibles through a digital metric methodology by using descriptive, inferential, and multivariate statistical analysis to identify which parameters are the most dimorphic and which are the best sex predictors. Thirty-three mandibles (14 females and 19 males) and personal belongings were photographically registered with code and sex. Data was collected using tomography, and measurements were made using the Simplant Pro software. The maximum and minimum width of the mandibular ramus, condylar height, coronoid process height, mandibular symphysis height, mandibular angle, bi-mental, bi-antegonial, bi-gonial and bi-condylar distances, and maximal mandibular length were registered. Statistical analysis was performed using IBM® SPSS. The results showed statistically significant differences for the following parameters: coronoid process height, condyle height, the maximum length of the mandible, and the minimum width of the mandibular ramus. In the multivariate statistical analysis, it was possible to identify the coronoid process height as the best sex predictor accurately in 72.2% of cases. This allows for easier differentiation between female and male mandibles with an accuracy of 64.3% and 78.9%, respectively. It was possible to conclude that the coronoid process height is the most dimorphic parameter and the best sex predictor in the sample.

Radiographic changes after alveolar ridge preservation using autogenous raw tooth particles versus xenograft: A prospective controlled clinical trial.

OBJECTIVE: The use of extracted teeth has been introduced as an option for bone grafting. However, the current method requires special machines and solutions, posing significant time and cost. The aim of this study was to evaluate the clinical performance of autogenous raw tooth particles (RTP), a grafting material made from a ground tooth using basic equipment, for alveolar ridge preservation. MATERIALS AND METHODS: Twenty-three patients (12 study/11 control), having 14 and 13 sites were included for the study and control groups (commercially available xenograft), respectively. Radiographic measurements were taken at the baseline and the 4-month follow-up appointment. Furthermore, a questionnaire survey concerning the general preference of the type of graft to receive (if needed), before and after knowing the price, was distributed at the completion of the procedure for patients to answer. RESULTS: Alveolar ridge width change was -1.03 ± 0.64 and -0.84 ± 0.35 for the study and the control groups, respectively. Regarding the height, the study group showed a buccal and lingual change of -0.66 ± 0.48 and -0.78 ± 0.81, respectively, while this was -0.78 ± 0.56 and -0.9 ± 0.41 for the xenograft group. There was no statistically significant difference between the groups. Patients preferred the raw tooth particles over other grafting materials (p = .01). CONCLUSION: No core biopsies were taken to evaluate bone formation, which should be done in future studies. Within its limitations, the current study demonstrated that RTP graft could be an alternative graft for bone augmentation, offering a new cost-effective option for clinicians when available.

Comparison of Upper Central Incisor Torque in the ClinCheck® with and without CBCT Integration: A Cross-Sectional Study.

Controlling root movement is one of the greatest challenges in orthodontic treatment with aligners, like Invisalign® aligners. Cone Beam Computed Tomography (CBCT) integration into ClinCheck®, enabling bone and root visualisation, allows a more accurate follow-up of the teeth position. This study aims to compare torque measurements of the upper central incisors with and without CBCT and relate them to the upper incisor inclination and facial biotype. In a sample of 70 teeth, torque measurements were obtained by importing images into AutoCAD® software (version 2024). The angle between the tooth's long axis with CBCT duplicate and the tooth's long axis without CBCT was obtained to assess the difference. Statistically significant differences between torque measurements with and without CBCT were found, as well as between these measurements and the inclination of the upper incisors. No statistically significant differences were found among the facial biotypes. The average values of 27.8° ± 3.4° and 21.5° ± 3.2° were obtained for the angle between the axes. Torque without CBCT was lower than torque with CBCT, for the same tooth. The angle between the axes had a similar mean for both teeth. CBCT integration into ClinCheck® allows for a more correct torque measurement.

Comparative Analysis of Examination Methods for Periapical Lesion Diagnostics: Assessing Cone-Beam Computer Tomography, Ultrasound, and Periapical Radiography.

INTRODUCTION: Periapical lesions of teeth are typically evaluated using periapical X-rays (PA) or cone-beam computer tomography (CBCT); however, ultrasound imaging (US) can also be used to detect bone defects. A comparative analysis is necessary to establish the diagnostic accuracy of US for the detection of periapical lesions in comparison with PA and CBCT. OBJECTIVES: This study aimed to evaluate and compare the measurement precision of US against PA and CBCT in detecting periapical lesions. METHODS: This study included 43 maxillary and mandibular teeth with periapical lesions. All teeth were examined clinically, radiographically, and ultrasonographically. Observers evaluated and measured the periapical lesions on CBCT, PA, and US images. RESULTS: The comparison of lesion size showed that it differs significantly between the different methods of examination. A statistically significant difference was found between CBCT and US (mean difference = 0.99 mm, 95% CI [0.43-1.55]), as well as between CBCT and PA (mean difference = 0.61 mm, 95% CI [0.17-1.05]). No difference was found between the US and PA methods (p = 0.193). CONCLUSION: US cannot replace PA radiography in detecting pathologies but it can accurately measure and characterize periapical lesions with minimal radiation exposure. CBCT is the most precise and radiation-intensive method so it should only be used for complex cases.

Radiological evaluation of middle meningeal artery by 3D rotational angiography.

PURPOSE: This study aimed to evaluate the topographic features and branches of the middle meningeal artery (MMA) by three-dimensional rotational angiography (3DRA) and describe its variations' radiological classification based on previous clinical examples of cadaver studies and literature. METHODS: We consecutively evaluated 87 cerebral hemispheres, including 32 females and 49 right sides between May 2020 and December 2021 who had undergone unilateral or bilateral cerebral and carotid artery 3D rotational angiography imaging by CCA injection and between 18 and 76-years-old. Maximum intensity projection images with 10-30 mm slice thickness were used for the morphological evaluations and measurements of MMA and its foramen, canal, and branches. RESULTS: The diameters of the common carotid artery, internal carotid artery, and external carotid artery were significantly smaller in females than in men (p = 0.021, 0.021, and <0.001, respectively). According to the branching pattern, the most common pattern of the MMA was Type Ia (49.4%). The ophthalmic artery completely originated from MMA in the 1 (1.1%) cerebral hemisphere. The MMA arises from the ophthalmic artery in 2 cerebral hemispheres (2.3%), and the ophthalmic artery and maxillary artery in 2 cerebral hemispheres (2.3%). CONCLUSION: It was observed that the branching pattern may show differences when compared to the cadaver studies with a radiologic evaluation with 3D-RA.

A rare case of persistent postendodontic symptomatic maxillary central incisor with aberrant canal configuration confirmed by cone-beam computer tomography and its nonsurgical management by retreatment.

Maxillary central incisor is considered the tooth with least anatomical variations. In literature, the prevalence of single root and single canal in maxillary central incisor has been reported as 100%. Only a handful of case reports suggesting more than one root or one canal are available and are mostly associated with developmental anomalies such as gemination and fusion. This article describes a rare case report of retreatment of a maxillary central incisor with two roots with normal clinical crown which was confirmed by cone-beam computer tomography (CBCT). A 50-year-old Indian male patient presented with pain and discomfort on a root canal-treated anterior tooth. Pulp sensibility testing of left maxillary central incisor was negative. Intraoral periapical digital radiograph revealed an obturated canal with suspected outline of a second root which got confirmed with cone shift technique. The tooth was treated under dental operating microscope during which two canals were located and retreatment was completed. Postobturation, CBCT was performed to study the root and canal morphology. Clinically and radiographically, all the follow-up examinations revealed an asymptomatic tooth without any active periapical lesion. The present case report emphasizes the fact that clinicians should approach each case with an open mind having a thorough knowledge of the normal tooth anatomy and should suspect variations in every case to ensure successful endodontic outcome.

Evaluation of Dental Root Development Regarding Maxillary Canine Eruption Status after Secondary Alveolar Bone Grafting in Patients with Cleft Lip and Palate.

In children born with cleft lip and palate, the timing of the secondary alveolar bone graft (SABG) is crucial to its success; this involves estimating the eruption of the permanent maxillary canine. Altered dental eruption in this patient group gives impetus to the identification of dental developmental factors concerning maxillary canine eruption, which may steer the clinical decision of SABG timing. Records of over nine hundred patients who received SABG with pre- and post-operative cone beam computed tomography (CBCT) scans were analyzed for inclusion and divided into two groups (erupting or non-erupting canine after SABG). Roots of the maxillary canines and premolars were segmented from the cementoenamel junction then linear and volumetric measurements were performed. The pre- and post-operative root length and volume differences were calculated and compared statistically using independent sample tests and paired t-tests. No statistically significant differences were found in the volume change (%), or reciprocal of mean root length in the erupted and unerupted groups in the canine, first premolar, or second premolar roots except for an association between the post-operative dental root length of the canine and the maxillary canine eruption status. Therefore, assessment of root development from pre-treatment CBCT scans was not deemed worthy from a diagnostic perspective.

A Comparative Study of Temporomandibular Joints in Adults with Definite Sleep Bruxism on Magnetic Resonance Imaging and Cone-Beam Computer Tomography Images.

OBJECTIVE: The aim was to study the imaging characteristics of the temporomandibular joint (TMJ) of definite sleep bruxers through magnetic resonance imaging (MRI) and cone-beam computer tomography (CBCT). METHODS: Nineteen definite sleep bruxers diagnosed by polysomnography and twenty asymptomatic non-bruxers matched by age, gender, and education level participated in this study. After obtaining MRI and CBCT images of all TMJs of the subjects, evaluation and measurement were conducted, respectively. The analyzed parameters included disc position, disc configuration, joint effusion (JE), joint space or condyle position, and condylar bony changes. RESULTS: Of the 38 joints in the study group, disc deformity and disc displacement of TMJs were both 57.9% when the mouth was closed, and 76.3% showed condylar bony changes, while when the mouth was open, 82% of all TMJs showed physiological biconcave discs. Comparison of joint space revealed that the anterior space was larger in the study group. There was no significant difference between the mild and the moderate to severe sleep bruxism subgroups in the changes of TMJ. CONCLUSION: The results demonstrated that a higher prevalence of disc deformity, disc displacement, JE, and condylar bony changes occurred in temporomandibular joints of sleep bruxers. These changes were not related to the severity of sleep bruxism.

Three-dimensional radiographic assessment of the mandibular retromolar donor site in different vertical facial growth types.

PURPOSE: To assess volumetrically, the impact of vertical facial growth types (VGFT) on the retromolar area as a bone donor site MATERIAL AND METHODS: 60 cone beam computed tomography (CBCT) scans of adult individuals were classified in three groups according to their SN-GoGn angle: hypodivergent group (hG) (33.33%), normodivergent group (NG) (30%) and hyperdivergent group (HG) (36.67%). Total harvestable bone volume and surface (TBV and TBS respectively), total cortical and cancellous bone volume (TCBV and TcBV respectively) and the percentage of cortical and cancellous bone volume (CBV and cBV respectively) were evaluated. RESULTS: The whole sample showed a mean TBV of 1220.99±448.81mm³ and a mean TBS of 940.29±259.93mm². Statistically significant differences were found between the different outcome variables and the vertical growth patterns (p<0.001). TBS differs for the different vertical growth patterns with the highest mean of TBS observed in the hG group. TBV also significantly differs between the different vertical growth patterns (p<0.001) with the highest mean observed for the hG individuals. Significant differences in percentages of cBV and CBV were present between the hyper-divergent groups and the other groups (p<0.001) with the hyper-divergent group having the lowest percentage of CBV and the highest percentage of cBV. CONCLUSION: hypodivergent individuals tend to have thicker bone blocks that can be used in onlay technique while thinner bone blocks harvested from hyperdivergent and normodivergent individuals can be used in three-dimensional grafting approach.

Accuracy of dental implant placement using static versus dynamic computer-assisted implant surgery: An in vitro study.

OBJECTIVES: This in-vitro study compared the accuracy of implant placement using static versus dynamic computer-assisted implant surgery (CAIS) at two implant sites. METHODS: Partially edentulous maxillary models were 3D-printed, and two implants (Straumann TL RN 4.1 × 10 mm) were inserted in FDI positions 15 and 16 per model using two CAIS approaches (10 models per approach). A three-dimensional (3D) reconstruction tool was used for implant planning, surgical guide design, and measuring implant positioning accuracy. In static CAIS, the implants were placed with 3D-printed surgical guides (n = 20); in dynamic CAIS, real-time navigation was performed (n = 20). Primary outcomes were defined as coronal and apical global deviation as well as angular deviations and deviation comparison between implants placed at positions 15 and 16; the secondary outcome was the bi-directional deviation in mesial-distal, buccal-palatal, and apical-coronal direction. RESULTS: The mean coronal and apical global deviation for static CAIS for implant positions 15 were 0.88±0.31 mm and 1.45±0.37 mm, and for implant position 16 were 0.67±0.31 mm, and 1.07±0.32 mm, respectively. In dynamic CAIS, the mean coronal and apical global deviation for implant position 15 were 0.97±0.32 mm and 1.58±0.56 mm, and for implant position 16 were 0.79±0.29 mm and 1 ± 0.37 mm, respectively. Buccal-palatal deviation was higher using static CAIS, and mesial-distal deviation was higher in dynamic CAIS. In position 15, mesial-distal deviation at the apex and the platform were lower in static approaches than in dynamic ones. In implant position 16, buccal-palatal deviation at the apex was lower in the dynamic group than with static ones. For bi-directional analysis, buccal-palatal deviation at the platform (P = 0.0028) and mesial-distal deviation at the apex (P = 0.0056) were significantly lower in molar sites using static CAIS. Mesial-distal deviation at the apex (P = 0.0246) revealed significantly lower values in position 16 following dynamic CAIS. CONCLUSIONS: Both static and dynamic CAIS resulted in accurate implant placement. However, dynamic CAIS exhibited higher deviation in the mesial direction in an in-vitro setting. In addition, the implant site affects the accuracy of both CAIS approaches. CLINICAL SIGNIFICANCE: Both static and dynamic CAIS demonstrate high accuracy for guided implant placement..

Using Cone Beam Computed Tomography for Radiological Assessment Beyond Dento-maxillofacial Imaging: A Review of the Clinical Applications in other Anatomical Districts.

BACKGROUND: Cone Beam Computed Tomography (CBCT) represents the optimal imaging solution for the evaluation of the maxillofacial and dental area when quantitative geometric and volumetric accuracy is necessary (e.g., in implantology and orthodontics). Moreover, in recent years, this technique has given excellent results for the imaging of lower and upper extremities. Therefore, significant interest has been increased in using CBCT to investigate larger and non-traditional anatomical districts. OBJECTIVE: The purpose of this work is to review the scientific literature in Pubmed and Scopus on CBCT application beyond head districts by paying attention to image quality and radiological doses. METHODS: The search for keywords was conducted in Pubmed and Scopus databases with no back-date restriction. Papers on applications of CBCT to head were excluded from the present work. From each considered paper, parameters related to image quality and radiological dose were extracted. An overall qualitative evaluation of the results extracted from each issue was done by comparing the conclusive remarks of each author regarding doses and image quality. PRISMA statements were followed during this process. RESULTS: The review retrieved 97 issues from 83 extracted papers; 46 issues presented a comparison between CBCT and Multi-Detector Computed Tomography (MDCT), and 51 reviewed only CBCT. The radiological doses given to the patient with CBCT were considered acceptable in 91% of cases, and the final image quality was found in 99%. CONCLUSION: CBCT represents a promising technology not only for imaging of the head and upper and lower extremities but for all the orthopedic districts. Moreover, the application of CBCT derived from C-arms (without the possibility of a 360 ° rotation range) during invasive investigations demonstrates the feasibility of this technique for non-standard anatomical areas, from soft tissues to vascular beds, despite the limits due to the incomplete rotation of the tube.

Is it necessary to remove bone-impacted teeth? A retrospective study.

BACKGROUND: In clinical practice, it is risky to extract bone-impacted teeth and they're prone to a variety of complications, such as pathological fracture, adjacent tooth fracture, maxillary sinus perforation, and so on, making it difficult for clinicians to decide whether to extract them. PURPOSE: In order to illustrate our opinions on the possibility of extracting full third molars (M3), 360 examples of complete third molars were analyzed in this study. MATERIALS AND METHOD: We investigated 2189 patients, and 261 of them provided CBCT images of 360 teeth. assessing the degree of second molar(M2) root absorption in connection to age, impacted relationship, contact part, calculating the odds ratio (OR) and 95% confidence interval using the Logistic regression analysis equation. RESULT: Bone-impacted M3 occurred in 11.92% (261/2189) of patients with "impacted teeth" diagnoses. There was a significant difference between the occurrence of M2ERR and the contact parts (P value<0.001), and only the type of vertical impaction differed significantly from Level 3 (P < 0.05). CONCLUSIONS: 1) M3 should be removed if root resorption has not occurred in M2. 2) Root resorption is more likely to occur when M3 crown and M2 apical contact. 3) Enough experience, precise preoperative assessment can reduce the dangers to a minimum.

Diagnosis of Organizing Pneumonia with an Ultrathin Bronchoscope and Cone-Beam CT: A Case Report.

Organizing pneumonia (OP) is a pulmonary disease histopathologically characterized by plugs of loose connective tissue in distal airways. The clinical and radiological presentations are not specific and they usually require a biopsy confirmation. This paper presents the case of a patient with a pulmonary opacity sampled with a combined technique of ultrathin bronchoscopy and cone-beam CT. A 64-year-old female, a former smoker, was admitted to the hospital of Reggio Emilia (Italy) for exertional dyspnea and a dry cough without a fever. The history of the patient included primary Sjögren Syndrome interstitial lung disease (pSS-ILD) characterized by a non-specific interstitial pneumonia (NSIP) radiological pattern; this condition was successfully treated up to 18 months before the new admission. The CT scan showed the appearance of a right lower lobe pulmonary opacity of an uncertain origin that required a histological exam for the diagnosis. The lung lesion was difficult to reach with traditional bronchoscopy and a percutaneous approach was excluded. Thus, cone-beam CT, augmented fluoroscopy and ultrathin bronchoscopy were chosen to collect a tissue sample. The histopathological exam was suggestive of OP, a condition occurring in 4-11% of primary Sjögren Syndrome cases. This case showed that, in the correct clinical and radiological context, even biopsies taken with small forceps can lead to a diagnosis of OP. Moreover, it underlined that the combination of multiple advanced technologies in the same procedure can help to reach difficult target lesions, providing proper samples for a histological diagnosis.

Cone-Beam Computed Tomographic Evaluation of Canal Morphology of Mesiobuccal Root of Maxillary Molars in Saudi Subpopulation.

Introduction: The purpose of this study was to analyze the canal configuration of mesiobuccal root (MBR) of the maxillary molars in the Saudi subpopulation using cone-beam computed tomography (CBCT) and to compare if there is any gender and arch variation. Methodology: In this cross-sectional retrospective evaluation study, analysis of CBCT scans of MBRs of 400 maxillary first and second molars was done that has undergone CBCT scanning for diagnostic/treatment purposes in the private clinic of Jeddah, KSA. Statistical analysis was performed using Student's t-test and Chi-square test. Results: Type I, II, and III canal configurations have been reported to be the most common morphologies in the MBR in both first and second molars, with the incidence of 20.25% (81), 17.25% (69), and 17.25% (69), respectively. Type I canals were significantly (P < 0.001) more common in tooth #17 and #27, Type II canals were significantly (P < 0.001) more seen in tooth #26, Type 3 canals were more seen in tooth #27, but there is no statistically significant association. Supplemental canal configurations which were classified by Gulabivala as Type I, Type II, and Type IV were also seen. Furthermore, 93 additional unclassified canal configurations were also found. Conclusion: The data indicate high prevalence of MB2 canals with varying canal configurations. Preoperative CBCT imaging should always be done in tooth-like maxillary molars, to understand the complex configurations and variations and to achieve higher success while performing root canal treatment.

Three-Dimensional (3D) Stereolithographic Tooth Replicas Accuracy Evaluation: In Vitro Pilot Study for Dental Auto-Transplant Surgical Procedures.

After immediate tooth extraction or after alveolar socket healing, tooth transplants are increasingly used for functional restoration of edentulous maxillary areas. Recent studies have shown the periodontal ligament (PDL) viability and the tooth housing time in the adapted neo-alveolus as key factors for transplantation success. During surgical time, 3D stereolithographic replicas are used for fitting test procedures. In this paper, the accuracy of 3D dental replicas, compared with the corresponding natural teeth, is assessed in surgical transplantation. Lamb skulls were selected and submitted to Cone Beam Computer Tomography (CBCT). Scanning information, converted into Standard Digital Imaging and Communications in Medicine (DICOM) and Standard Triangulation Language (STL), was sent to the Volux X-ray Centre for 3D replica printing. After the tooth extractions, all lambs' incisors were measured with a digital caliber and compared with the 3D replicas. Volume and dimensional error values were evaluated. All replicas showed macroscopically smaller volume (45.54%). Root replicas showed higher variations compared with the crown areas, with several unreplicated apical root areas. The cement-enamel junction tooth area was replicated quite faithfully, and the base area relative error showed 9.8% mean value. Even further studies with a larger number of replicas are needed. Data obtained confirmed high volumes of macroscopic discrepancies with several unreproduced apical root sites. The achieved accuracy (90.2%) confirmed that the 3D replicas cannot be used to reduce the surgical time during transplantation predictable procedures.

Radiological evaluation of maxillary artery and descending palatine artery in the pterygopalatine fossa by 3D rotational angiography.

PURPOSE: The aim of this study is to evaluate the branching patterns and topographical features of the third part of the maxillary artery (t-MA) and descending palatine artery (DPA) by 3-Dimensional Rotational Angiography (3DRA) images and to define the radiological classification of their variations, based upon the previous cadaveric studies and a review of the literature. METHOD: This study was conducted from May 2020 through June 2021. All consecutive adult patients who were examined with 3D-RA were enrolled in the study. The morphological evaluations and measurements of t-MA, DPA and their branches were made on maximum intensity projection images with 10-20 mm slice thickness. RESULTS: Eighty-five hemifaces, including 58 females and 45 right sides, were evaluated. The diameter of the t-MA was measured as 1.73 ± 0.30 mm. The most common pattern of the t-MA according to its course was loop type (63/85, 74.1%) and according to branching pattern was Type Ib (29/85, 34.1%). The mean diameter of DPA was 1.19 ± 0.20 mm. The DPA presented as a single trunk in 11/85 cases. Type II, which was defined as one lesser palatine artery originating from distal-DPA, was the most common morphological variation (51.8%). CONCLUSIONS: 3DRA imaging provides valuable information for vascular anatomical studies. The most common morphological variation related to t-MA, DPA is the distal branching pattern.

Comparison between Conventional Modality Versus Cone-Beam Computer Tomography on the Assessment of Vertical Furcation in Molars.

This study aimed to assess the accuracy of diagnosis of vertical furcation subclass in molars using periapical radiographs (PAs) and clinical chartings compared against cone-beam computer tomography (CBCT) as the gold standard. The protocol involved examiners with different levels of experience. This retrospective radiographic study retrieved 40 molar teeth with full periodontal chartings, PAs, and CBCT records. Fifteen examiners with different levels of experience evaluated the PAs and periodontal chartings to assess the vertical depth of furcation and, thus, the vertical subclassification. CBCT was used as the gold standard for comparison. The accuracy of vertical furcal depth measured was assessed together with the accuracy of vertical subclassification assignment. The reliability of the conventional diagnostic modality among the examiners was also evaluated. A linear mixed model adjusted for the CBCT vertical furcal depth measurement was constructed to determine if tooth position, horizontal furcation distribution, and examiner experience level affect the bias in the vertical depth of furcation measurement. The reliability of the conventional periodontal diagnostic method in measuring vertical furcal depth was found to be fair, while vertical subclass assignment was moderate. Significantly better reliability during subclass assignment was found with mandibular molars (p < 0.001) and in maxillary molars with isolated buccal class II furcation. Within the study's limitations, conventional periodontal diagnostics based on periapical radiographs and clinical periodontal chartings appear to be in poor to fair agreement with CBCT (gold standard) when measuring the vertical depth of furcation. Examiners with the least experience were more prone to bias when estimating the vertical furcal depth.

Rapid maxillary expansion treatment increases mid-facial depth in early mixed dentition.

Objective: To evaluate the effects of rapid maxillary expansion (RME) on mid-facial depth in early mixed dentition and to investigate the relationship between change in mid-facial depth and maxillary sinus and nasal cavity. Methods: A total of 35 patients with mixed dentition treated with a Haas expander were included in this retrospective study. All patients underwent a cone-beam computed tomography scan before and after rapid maxillary expansion. The Wilcoxon signed-rank test was performed to evaluate the changes in maxillary width, facial depth, maxillary sinus, and nasal cavity volume before and after expansion. Multiple linear regression analysis was applied to evaluate the correlations among them. Results: The hard and soft tissue facial depth in the middle third increased significantly (P < 0.001). The gain on the outer sagittal plane (1.04-1.52 mm) was slightly bigger than that on the inner sagittal plane (0.91-1.30 mm). Maxillary width and nasal cavity width increased 3.42 ± 0.93 mm (P < 0.001) and 2.25 ± 0.77 mm (P < 0.001), respectively, after treatment. A gain was also achieved in both nasal cavity volume (2,236.15 mm3, P < 0.001) and maxillary sinus volume (1,227.33 mm3, P < 0.001). Multiple linear regression analysis showed that with the increase in maxillary sinus volume, the facial depth increased as well (B = 0.455-0.683, P < 0.05). Also, statistically significant correlations were found between nasal width and nasal cavity volume (B = 0.384, P < 0.05). Conclusion: The depth of the middle third face increased significantly. The facial depth increase was related to the enlargement of maxillary sinus volume, while the nasal cavity volume gain was related to the nasal width increase. This indicated that RME might enhance the fullness of the mid-face and facilitate the patency of nose breathing.

Preliminary efficacy analysis of block iliac bone grafting in patients with alveolar cleft in mixed dentition.

OBJECTIVES: To investigate the efficacy of block iliac bone grafting in patients with unilateral alveolar cleft in mixed dentition. METHODS: A retrospective study was conducted on patients with unilateral alveolar clefts in mixed dentition who were treated in the Department of Oral and Maxillofacial Surgery, Fujian Medical University Union Hospital. All patients underwent unilateral alveolar cleft bone graft repair with autogenous block iliac bone blocks. The healing of bone blocks was analyzed at 1 week and 6-12 months after surgery. Mimics software was used for the three-dimensional reconstruction and volumetric measurement of the iliac bone blocks on the follow-up imaging data of 15 patients aged 9-12 years without the eruption of canines before surgery, and the bone resorption rate of the iliac bone blocks was comparatively analyzed. RESULTS: In the 37 patients, bone grafting was successful in 32 and failed in five. The success rate of bone grafting was 86.5%. In 15 patients aged 9-12 years without the eruption of canines before surgery, eruption through the bone graft area was observed in two patients 6-12 months after the operation. Cone beam computer tomography showed that the grafted bone block exhibited good bony connections, and its resorption mainly occurred on the crests and palatal sides of the alveolar ridge. Bone resorption rates varied considerably between patients with a mean bone resorption rate of 39.0%±13.8% at 6-12 months after surgery. CONCLUSIONS: For patients in mixed dentition, bone grafting with block iliac bone can achieve better osteogenesis effect.

Tooth and pulp chamber automatic segmentation with artificial intelligence network and morphometry method in cone-beam CT / Segmentación automática de cámaras dentales y pulpares con red de inteligencia artificial y método de morfometría en TC de haz cónico

SUMMARY: This study aims to extract teeth and alveolar bone structures in CBCT images automatically, which is a key step in CBCT image analysis in the field of stomatology. In this study, semantic segmentation was used for automatic segmentation. Five marked classes of CBCT images were input for U-net neural network training. Tooth hard tissue (including enamel, dentin, and cementum), dental pulp cavity, cortical bone, cancellous bone, and other tissues were marked manually in each class. The output data were from different regions of interest. The network configuration and training parameters were optimized and adjusted according to the prediction effect. This method can be used to segment teeth and peripheral bone structures using CBCT. The time of the automatic segmentation process for each CBCT was less than 13 min. The Dice of the evaluation reference image was 98 %. The U-net model combined with the watershed method can effectively segment the teeth, pulp cavity, and cortical bone in CBCT images. It can provide morphological information for clinical treatment.

RESUMEN: El objetivo del presente estudio fue extraer estructuras dentarias y óseas alveolares desde imágenes CBCT automáticamente, lo cual es un paso clave en el análisis de imágenes CBCT en el campo de la estomatología. En este estudio, se utilizó la segmentación de tipo emántica para la segmentación automática. Se ingresaron cinco clases de imágenes CBCT marcadas, para el entrenamiento de la red neuronal U-net. El tejido duro del diente (incluidos esmalte, dentina y cemento), la cavidad de la pulpa dentaria, hueso cortical, hueso esponjoso y otros tejidos se marcaron manualmente en cada clase. Los datos se obtuvieron de diferentes regiones de interés. La configuración de la red y los parámetros de entrenamiento se optimizaron y ajustaron de acuerdo con un análisis predictivo. Este método se puede utilizar para segmentar dientes y estructuras óseas periféricas mediante CBCT. El tiempo del proceso de segmentación automática para cada CBCT fue menor a 13 min. El "Dice" de evaluación de la imagen de referencia fue de 98 %. El modelo U-net combinado con el método "watershed"puede segmentar eficazmente los dientes, la cavidad pulpar y el hueso cortical en imágenes CBCT. Puede proporcionar información morfológica para el tratamiento clínico.