Computed Tomography Studies Research Articles

Assessment of mandibular asymmetry in different skeletal malocclusions and vertical patterns in adult individuals: A cone-beam computed tomography study

The study aims to measure the mandibular condylar height (CH), ramus height (RH), total height (CH+RH), asymmetry index, and condylar volume (Cvol) in individuals with different anteroposterior and vertical skeletal discrepancies.The study sample consisted of 131 subjects (60 females and 71 males) with a mean age of 35.06 ± 12.79 years. Pre-existing CBCT images were divided into groups according to the anteroposterior and vertical skeletal discrepancies. The investigator analyzed the data using t-tests to assess the mandibular bilateral sides of the individuals and gender differences. The mean difference between groups was determined using a one-way analysis of variance (ANOVA). The Chi-square test was used to study the association between the asymmetry index and groups.Each individual's bilateral sides exhibited statistically significant differences in CH, RH, and Cvol (P = 0.033, P = 0.039, P = 0.005, respectively), but not in CH+RH (P = 0.458). There were, however, statistically significant gender differences in CH+RH (P < 0.001). Skeletal Class III and hypodivergent groups revealed the highest linear and volumetric values compared to other groups. The asymmetry index was increased in CH (P = 0.006) and Cvol (P = 0.002) in skeletal Class II subjects.Significant differences in CH, RH, and Cvol were found on the right and left sides of the same individual. This study found increased linear and volumetric values in males, skeletal Class III, and hypodivergent subjects. Class II individuals had an increased CH and Cvol asymmetry index. This study highlights in-depth knowledge of mandibular asymmetry, which is extremely important to achieve an accurate diagnosis and provide the best treatment outcome.

Evaluation of interorifice distance in permanent mandibular first molar with middle mesial canal in Bengaluru city, Karnataka: A cone-beam computed tomography study

Aim: Analysis of interorifice distance (IOD) between mesiobuccal and mesiolingual canals in the presence of middle mesial canal (MMC) variants in mandibular first permanent molar (MFPM) in an Indian subpopulation. To categorically assess the prevalence of MMC variants considering variation in factors of age and gender. Methods: Analysis of preoperative cone-beam computed tomography (CBCT) images was performed on 256 MFPM. MMCs were classified as fin, confluent, or independent as per the classification given by Pomeranz et al. (1981). Orthogonal slices from pulpal floor to 4 mm below were used to measure mean IOD using the CBCT software tool. Data were subjected to descriptive statistics. The Chi-square test was used for further analysis. Results: The prevalence of independent MMC was 4.7% (n = 12), confluent 14.6% (n = 37), and fin 8.7% (n = 22). The mean IOD measured for fin variant was 3.12 ± 0.512 mm, 3.31 ± 0.402 mm for confluence variant, 3.72 ± 0.493 mm for independent MMC, and 3.36 mm ± 0.579 for two-canal variant. Significant association (P = 0.001) was observed between age, gender, and overall detection of MMC, wherein the presence of fin (8.6%) and confluent (12.9%) configurations was higher (P = 0.003) in individuals ≤40 years. There was increased IOD in females (17.9%) than males (10.3%), for confluent, independent, and two-canal configuration (P = 0.04; =0.01, =0.001). Decreased IOD was observed in individuals >40 years for two-canal configurations (P = 0.05). Conclusion: Preoperative CBCT assessment of MFPM aids in the detection of MMC. According to the results of this study, individuals aged ≤40 years have shown higher prevalence of fin and confluent variants. Increased IOD was seen in females for confluent, independent, and two-canal configurations. Decreased IOD was seen in individuals aged >40 years having two-canal configuration. Thus, root canal complexities vary with age and gender, and should be taken into consideration before endodontic treatment.

A rare case of hepatosplenic cat scratch disease

A female patient in her 60s, treated with oral corticosteroids for scleroderma diagnosed 11 years ago, visited our hospital complaining of a persistent fever and liver dysfunction. She was treated with antibiotics, but her fever continued. Abdominal ultrasonography revealed multiple hypoechoic splenic masses. Splenic masses revealed multiple masses with no contrast effect in arterial and portal phases and nuclear in equilibrium phase by contrast computed tomography study, as well as hyperintensity masses with low signal areas in magnetic resonance imaging T2-weighted images. Liver tissue was obtained by percutaneous liver biopsy, and histological findings showed epithelioid cell granulomas without tumor cells. Further interview and physical examination revealed scratch scars from domestic cats and left axillary lymph node swelling. Hence, a cat scratch disease was suspected. She was diagnosed with cat scratch disease by serum indirect immunofluorescence. Her fever was resolved with minocycline administration. Therefore, persistent fever with splenic masses should be suspected of hepatosplenic cat scratch disease.

A comparative analysis of dual-axis implants placed into maxillary anterior extraction sockets versus virtual planning with uniaxial implants: A simulated cone beam computed tomography study of implant length and diameter.

The biaxial nature of the anterior maxilla poses a surgical and restorative challenge in implant dentistry. The present study sought to investigate the apical socket perforation rate (ASPR) from a simulated uniaxial implant placement and to determine the effect of implant length and diameter on ASPR when a uniaxial implant was placed compared with the orientation of the pre-existing dual-axis implant. Cone beam computed tomography (CBCT) scans from the database of three private practices were searched for patients who received dual-axis implants within the esthetic zone in immediate tooth replacement therapy. A uniaxial implant was virtually placed using the pre-existing screw access channel of the dual-axis implant as a reference. The closest length and diameter were selected for the simulated implant. ASPR by the uniaxial implant was recorded. In addition, the affordable maximum length of a corresponding uniaxial implant that would avoid apical socket perforation was measured. Eighty-one patients with a total of 101 dual-axis dental implants were selected for analysis. A simulated virtual surgical planning with uniaxial implants revealed high ASPR (48.51%). When the length of the uniaxial implant was reduced to 11 and 9 mm, ASPR was decreased to 41.58% and 20.79%, respectively. Dual-axis implant design effectively evades anatomical challenges in the anterior maxilla (esthetic zone). Considering the current evidence, efforts should be made to carefully consider the angular disparity between the extraction socket-alveolus complex and the future restorative emergence so that a harmonious biologic-esthetic result may be more predictably and consistently obtained.

Comparison of Maxillary Sinus Volumes in Individuals with Different Dentofacial Skeletal Patterns: A Cone-Beam Computed Tomography Study

Comparison of Maxillary Sinus Volumes in Individuals with Different Dentofacial Skeletal Patterns: A Cone-Beam Computed Tomography Study

A Retrospective Cone-Beam Computed Tomography Study of the Calcification Pattern, Prevalence, and Morphology of the Elongated Styloid Process

Introduction: A styloid process (SP) is considered extended if it is longer than 30 millimeters (mm), which falls between the typical range of 20 and 30 mm. Eagle’s syndrome (ES), a disease associated with the styloid process elongation (SPE), was originally recognized by otorhinolaryngologist “Watt Weems Eagle” in 1937. Aims: The calcification pattern, prevalence, and morphology of the SPE in a hospital-based population in Bhubaneswar were all objectively assessed in the study using cone-beam computed tomography (CBCT). Methods and Material: Radiographic records of 1027 patients have been recovered arbitrarily from the authentic records and assessed. The length of the SP was estimated and characterized by their morphology and calcification design. The collected data were analyzed using Statistical Package for the Social Sciences version 25 software. It was deemed statistically significant if the P value ≤ 0.05. Results: It was seen that 25.8% of the males had the presence of elongation as compared to 30.1% of females, which is 153 males out of 440, and 131 females out of 304 showed elongated SP. Conclusion: The SPE could be a coincidental radiography perception without symptoms. In this study, a substitute for CT or all panoramic radiographs for the estimation and assessment of the SP is the CBCT approach.

Influence of heat-treated retreatment files on the canal transportation and centering ability during retreatment: An in vitro cone beam computed tomography study

Influence of heat-treated retreatment files on the canal transportation and centering ability during retreatment: An in vitro cone beam computed tomography study

Comparative evaluation of canal transportation and canal centering ability in oval canals with newer nickel-titanium rotary single file systems - A cone-beam computed tomography study.

The purpose of this study was to evaluate and compare the centering ability and canal transportation of TruNatomy, OneCurve, and Jizai file systems to assess their performance in oval-shaped canals using cone-beam computed tomography imaging. Forty-two fully formed single-rooted mandibular premolars were selected with a buccolingual canal size 2-2.5 times the mesiodistal size at 5 mm from the apex, with 0°-10° canal curvature with a 5-6 mm radius, at 5 mm from the apex. The teeth were divided into three groups (n = 14) and prepared with TruNatomy, OneCurve, and Jizai files based on the manufacturer's instructions. Cone-beam computed tomographic images were taken before and after instrumentation. The canal transportation and centering ability was calculated at 3, 6, and 9 mm from the apex in both mesiodistal and buccolingual directions. Intergroup comparison was done using Kolmogorov-Smirnov test. Intragroup comparison was done using Freidman test. A comparison of categorical variables was done using the Chi-square test. The results obtained did not present any statistically significant difference between the three groups, with TruNatomy and OneCurve showing relatively lesser canal transportation and better centering ratio when compared to the Jizai file system. It can, therefore, be concluded that all three systems used in the study are capable of safely preparing root canals with minimal errors.

Centering Ability of F6 SkyTaper and RaCe Rotary Files: A Cone-Beam Computed Tomography Study

Centering Ability of F6 SkyTaper and RaCe Rotary Files: A Cone-Beam Computed Tomography Study

In vitro evaluation of the quality of obturation with capillary condensation technique and hybrid technique in teeth with simulated internal resorption cavity: A cone-beam computed tomography study

ABSTRACT Aim: The quality of obturation with recent capillary condensation technique and hybrid technique in teeth with artificial internal resorption cavity needs to be evaluated. Methods: Calculation of sample size was done with G*Power software (version 3.1.9.4) (effect size d = 1.46). Eighteen single-canal mandibular premolars were decoronated at the cementoenamel junction for standardization of specimen length as 12 mm. Biomechanical preparation was done with ProTaper Universal rotary file up to F4. Internal resorption cavity was prepared with #08 size round bur 6 mm from the apex. Samples were distributed randomly into two groups. Group I: teeth with bioceramic sealer (EndoSequence BC Sealer, Brasseler, USA) application using conventional technique and hybrid technique of obturation. Group II: capillary condensation technique of bioceramic sealer (EndoSequence BC Sealer, Brasseler USA) using single-cone gutta-percha obturation. The voids in three segments of the root canal were measured with cone-beam computed tomography using “OnDemand3D App” software. Data were statistically analyzed by one-way analysis of variance (ANOVA) and multiple comparisons of Tukey honestly significant difference tests with P &lt; 0.05. Results: The mean area of the void was 0.3963 ± 0.3299 mm2 for Group I and 0.4022 ± 0.4101 mm2 for Group II. There was a difference in the number of voids present in different sections of the root within a group with significance but not between the groups. Conclusion: Capillary condensation technique with single-cone obturation is comparable to conventional sealer application and hybrid technique of obturation for filling internal resorption cavity.

Radiological research methods in the diagnosis and treatment of patients with the parapharyngeal space tumors

The parapharyngeal space is a complex structure, being narrow and difficult for surgical approach. Surgical treatment is the main treatment for parapharyngeal space (PPS) tumors, it is performed on the basis of information obtained from imaging methods (computed tomography (CT) and magnetic resonance imaging (MRI)). Objective – to investigate the effectiveness of advanced visualization of radiological research methods in the diagnosis of the parapharyngeal space tumors in order to select the necessary tactics of surgical treatment. This retrospective study included 43 patients who underwent surgery for primary parapharyngeal space tumors from 2010 to 2021. 32 patients were treated in previous 10 years, 11 – patients who underwent examination and surgical treatment over the past 2 years with advanced methods of MRI and CT to select a safe surgical approach. Patients of the 2nd group underwent advanced MRI and CT studies in order to choose the correct method of surgical approach and prevent postoperative complications and recurrence. The histological conclusion in 90.1% of the operated patients confirmed the preliminary data of MRI perfusion regarding the probable histological structure of the neoplasm. Due to a comprehensive preoperative study, in 81.8% of patients in this group transoral approach was used. Our experience confirms the necessity for a thorough preoperative diagnostic procedure that should take advantage of imaging modalities (CT, MRI), especially new techniques (MRI-perfusion and diffusion weighted imaging).

Electrocardiographic Gating and Cerebral Perfusion Computed Tomography Option-Set Prevalence and Utilization Data From 62 Institutions in the United States.

To provide the radiology community with data to address the question: "Compared with peer institutions, is my institution efficiently using its electrocardiographic (ECG) gating and cerebral perfusion-capable computed tomography (CT) scanners?" In this retrospective study, we analyze 6 months of scanner utilization data from 62 institutions (299 locations, 507 scanners) to identify scanners capable of performing ECG gating and perfusion CT studies. We report the number of ECG gating/perfusion-capable scanners and locations as a function of the total number of locations and scanners in each institution. We additionally regress the number of ECG-gated and perfusion examinations on (1) the number of locations/scanners capable of performing these examinations and (2) the fraction of the institution's CT examination volume that requires ECG gating or perfusion. We provide look-up tables so an institution can compare its ECG-gated/perfusion examination volume to other institutions with similar ECG-gated/perfusion examination fractions and capable scanners. We detected an effect of both ECG-gating examination fraction and the number of ECG gating-capable scanners on ECG-gated examination volume ( χ21 = 77.5 [ P < 0.001] and χ21 = 64.2 [ P < 0.001], respectively). Similar results were obtained for perfusion examination fraction and perfusion-capable scanners as they relate to perfusion examination volume ( χ21 = 51.6 [ P < 0.001] and χ21 = 45.2 [ P < 0.001], respectively). The number of ECG gating/perfusion-capable scanners and locations within an institution were found to positively correlate with both the total number of locations and scanners within an institution ( P < 0.001 for all hypothesis tests). The study provides multi-institutional data on ECG gating and perfusion examination volumes that can be used to inform CT purchasing decisions.

The labiopalatal impacted canine: Accurate diagnosis based on the position and size of adjacent teeth: A cone-beam computed tomography study

Labiopalatal impacted canines (L-PICs) occur when the canines lie between central and lateral incisors, with their tip palatal to the central incisor and part of their crown labial to the lateral incisor. Because of their unusual position, they are often misdiagnosed, and their orthodontic resolution fails. This study aims to provide clinicians with pathognomonic features for early and accurate positional diagnosis of L-PICs. The L-PIC sample included 21 subjects with full diagnostic records. The control group of normally erupted canines was taken from a previous study. Clinical photographs, 2-dimensional radiographs, and cone-beam computed tomography were used to evaluate the positions of the adjacent incisors and first premolars, the canine incisor index, and the mesiodistal width of the lateral vs central incisors. Central incisors adjacent to L-PICs showed significant mesial root angulation, labial root inclination, and mesiolabial crown rotation, whereas lateral incisors presented significant distal root angulation, palatal root inclination, and mesiolabial crown rotation, in comparison to controls. The roots of the central and lateral incisors were divergent, in contrast to the controls, in which they were slightly convergent. The first premolar positions were not affected. The mean canine incisor index was significantly bigger in L-PICs vs the controls, suggesting a palatal canine. The lateral incisor widths were similar between the groups. This study provides the orthodontist with evidence-based clinical and radiographic red flags for diagnosing L-PIC, which may allow timely initiation of orthodontic treatment and correct planning of mechanotherapy.

Structural Cerebral Network Differences in Prodromal Alzheimer’s Disease and Prodromal Dementia with Lewy Bodies

Introduction: Alzheimer’s disease (AD) and dementia with Lewy bodies (DLB) have long prodromal phases without dementia. However, the patterns of cerebral network alteration in this early stage of the disease remain to be clarified. Method: Participants were 48 patients with mild cognitive impairment (MCI) due to AD (MCI-AD), 18 patients with MCI with DLB (MCI with Lewy bodies: MCI-LB), and 23 healthy controls who underwent a 1.5-Tesla magnetic resonance imaging scan. Cerebral networks were extracted from individual T1-weighted images based on the intracortical similarity, and we estimated the differences of network metrics among the three diagnostic groups. Results: Whole-brain analyses for degree, betweenness centrality, and clustering coefficient images were performed using SPM8 software. The patients with MCI-LB showed significant reduction of degree in right putamen, compared with healthy subjects. The MCI-AD patients showed significant lower degree in left insula and bilateral posterior cingulate cortices compared with healthy subjects. There were no significant differences in small-world properties and in regional gray matter volume among the three groups. Conclusions: We found the change of degree in the patients with MCI-AD and with MCI-LB, compared with healthy controls. These findings were consistent with the past single-photon emission computed tomography studies focusing on AD and DLB. The disease-related difference in the cerebral neural network might provide an adjunct biomarker for the early detection of AD and DLB.

Zero Echo Time vs. T1-Weighted MRI for Assessment of Cortical and Medullary Bone Morphology Abnormalities Using CT as the Reference Standard.

Conventional MR pulse sequences result in poor signal from low T2 cortical bone because the minimum achievable echo time is limited. A sequence resulting in improved bone contrast is desirable. To evaluate the image quality and diagnostic performance of grayscale inversion zero echo time imaging (GI-ZTE) and grayscale inversion T1-weighted imaging (GI-T1WI) compared with computed tomography (CT). Prospective. A total of 50 patients with musculoskeletal tumors or tumor-like diseases of the lower extremities having MRI and CT studies. GI-T1WI and GI-ZTE sequences at 1.5T. Assessed cortical and medullary bone morphology abnormalities using CT as the reference standard. Three radiologists scored the images quality and recorded nine metrics to assess the diagnostic performance. Differences in image quality were calculated using the Wilcoxon signed-rank test. The intraclass correlation coefficient (ICC) was used to analyze the agreement of quantitative lesion parameters between CT and MR sequences, as well as the interobserver reliability. A P value <0.05 was considered statistically significant. Image quality score was significantly higher for CT images than GI-TIWI images. Except for radiologist 3 [4(0) vs 4 (1)], there was no significant difference in scores between CT and GI-ZTE [radiologist 1: 4 (0) vs 4 (0), P=0.133; radiologist 2: 4 (0) vs 4 (0), P=0.085]. There was good-excellent agreement between both MR sequences and CT for size, lesion number, location, sclerotic rim, expanded shell, destruction pattern, and matrix mineralization for all radiologists (ICC: 0.636-1.000). The consistency of periosteal reaction and penetration of the cortex was fair to good (0.481-0.729) between GI-T1WI and CT and good to excellent between GI-ZTE and CT (0.682-0.852). GI-ZTE images had superior intermodality agreement with CT images and allowed visualization of more cortical bone detail than GI-T1WI images. 1. Stage 2.

The Influence of Brushing Motion on the Cutting Efficiency of Two Heat-Treated Endodontic Files: An In-Vitro Micro Computed Tomography Study

Background: To assess the cutting efficiency of two heat-treated endodontic files with a brushing motion in oval-shaped canals. Methods: A total of 10 intact lower molars with a single oval distal canal were selected and randomly divided into two groups according to the system used for shaping: 2Shape and Hyflex CM. The instrumentation was performed in two parts: a first shaping according to the manufacturer’s instructions and final shaping using 5 brushing motions on the distal, lingual, and buccal walls, avoiding the danger zones. Micro computed tomography (micro-CT) scans before and after the brushing motion were superimposed at all three levels: coronal, middle, and apical. Canal changes in buccolingual (ΔBL) and mesiodistal (ΔMD) dimensions were measured. Data were statistically analyzed by repeated-measures analyses of variance and the student t-test (p &lt; 0.05). Results: For ΔMD, no significant difference emerged between the 2Shape and Hyflex CM in the apical and coronal thirds. However, the cutting efficiency was significantly greater with the 2Shape in the middle third (p &lt; 0.05). Regarding ΔBL, no statistically significant difference was detected between 2Shape and Hyflex CM comparing the anatomical thirds, while 2Shape had a significant higher cutting efficiency considering the total BL diameter (p &lt; 0.05). Conclusions: Under the limits of a vitro study, the shaping procedure with 2Shape and brushing motion was more efficient than the Hyflex CM in the midroot levels in terms of ΔMD, and in total canal space for ΔBL. Both files ensured an effective mechanical preparation.

Prevalence of middle mesial canals in mandibular first molars in coastal Andhra population – A Cone beam computed tomography study

Introduction: Recognition of variations in root canal anatomy is an essential prerequisite for successful endodontic diagnosis and treatment. Most of the endodontic failures result from missed canals. The mandibular first molar has the most complex root canal system and a high percentage of treatment failures are due to the impossibility of locating, instrumenting and obturating the middle mesial canal (MM). There are very few studies available regarding the incidence of MM canal in mandibular first molar. The present study evaluated the prevalence of the middle mesial canals in mandibular first molars using cone beam computed tomography (CBCT). Materials and Methodology: CBCT images of mandibular first molars were collected from patients (n= 100) who had undergone CBCT imaging. The images were analyzed and the prevalence of MM canals were calculated. Results: The data were analysed using descriptive statistics. In total of 100 patients, 60 were women and 40 were men, with age range 11-60 years old. 21 MM canals were identified in this study. In this, 11 were female and 10 were male. The prevalence of the MM canal in mandibular first molar MM canals were identified in 21% (21/100). Conclusion: Within the limitations of the study, it can be concluded that though advanced techniques like troughing and magnification help in finding and negotiating MM canals, 3D radiographies like CBCT can be as used as valuable adjunct to the above mentioned methods. When these canals are treated, the success rate of the endodontic treatment would definitely increase. Clinical studies with long-term follow-ups are needed to determine the effect of preparation of MM canals on the outcome of nonsurgical endodontic treatment in mandibular first molars. Keywords: Cone Beam Computed Tomography, Mandibular First Molar, Middle Mesial Canal, Prevalence.

Three-Dimensional Analysis of Alveolar Bone Morphological Characteristics in Skeletal Class II Open Bite Malocclusion: A Cone-Beam Computed Tomography Study.

This cross-sectional research evaluated the morphological characteristics of alveolar bone in skeletal class II open-bite individuals compared to skeletal class II and class I non-open-bite individuals. A sample of 82 patients (all were in cervical vertebral stage 6) was divided into three groups (class II OB group, n = 29; class II NOB group, n = 29; class I NOB group, n = 24) according to bilateral molar relationship, ANB angle, and anterior overbite measured by cephalometric analysis. The evaluation was performed with specialized software (Mimics 21.0) and initial cone-beam computed tomography (CBCT) data. The alveolar bone height and thickness of the whole dentition area and alveolar crest level and root apex position of the incisors were measured with a series of appropriate CBCT images. One-way analysis of variance followed by the Tukey post hoc test and the Kruskall−Wallis test were performed for statistical comparisons. The class II open-bite group had increased alveolar bone height for the maxillary first molar and decreased alveolar bone height for mandibular molars compared to the class II non-open-bite group (p < 0.05 for both). Furthermore, there were significant negative correlations between the alveolar bone heights of the upper first and second molars (A6-height, A7-height) and overbite (both p < 0.01). The alveolar thicknesses of all measured teeth were generally reduced in the class II OB group.

Factors related to microimplant-assisted rapid palatal expansion in teenagers and young adults: A cone-beam computed tomography study

For patients with maxillary transverse deficiency, selecting an appropriate therapeutic method is important for the treatment effect and prognosis. Our study aimed to explore factors related to microimplant-assisted rapid palatal expansion (MARPE) in teenagers and young adults using cone-beam computed tomography. Twenty-five patients who underwent MARPE were included in this retrospective study from February 2014 to June 2019. Midpalatal suture density (MPSD) ratio, midpalatal suture maturation (MPSM), bone effect, dentoalveolar effect, and dental effect in maxillary first molar were evaluated using cone-beam computed tomography. Spearman correlation analysis was used to analyze the correlation between the MPSD ratio, MPSM, age, and the expansion amount generated by MARPE. Twenty-five patients (mean age, 19.84 ± 3.96 years; range, 15-29 years) with maxillary transverse deficiency were analyzed. Age was negatively correlated with bone expansion, alveolar expansion, and alveolar change (all P<0.05). There was a negative correlation between MPSM and nasal cavity variation, bone expansion, and alveolar change (all P<0.05). The bone expansion was negatively correlated with MPSD ratio 3 (r= -0.417; P<0.05) and MPSD ratio 4 (all P<0.05). Age, MPSM, and MPSD ratio were significantly related to the MARPE effect. Age, MPSM, and MPSD ratio should be considered when choosing MARPE.

Maxillary Sinus Dimensions in Skeletal Class I Chinese Population with Different Vertical Skeletal Patterns: A Cone-Beam Computed Tomography Study.

Due to the close relationship between the maxillary posterior teeth roots and the maxillary sinus floor, the maxillary sinus can significantly impact various dental treatments, including endodontic procedures and surgical apicectomy, periodontal flap surgery, surgical tooth extraction, dental implantation, and orthognathic surgeries. Specifically, in orthodontics, the location of the maxillary sinus floor may affect tooth movement and insertion of temporary anchorage devices (TADs). This study aims to evaluate the dimensions and location of the maxillary sinus in the Chinese orthodontic patient population with skeletal class I. Using cone-beam computed tomography (CBCT), the volumetric size, height, width, and depth of the sinus and the amount of alveolar bone below the sinus floor and buccal/palatal to the sinus wall were compared between patients of different genders and different vertical skeletal patterns. Unlike the previously reported skeletal class II population, the skeletal class I patients with different vertical patterns do not have significantly different size sinuses. On the other hand, males have larger maxillary sinuses in all parameters than females in the testing population. In addition, no significant correlation was noticed between the SN-MP angle and sinus dimensions or between the ANB angle and sinus dimensions. Nevertheless, the distance from the sinus floor to the alveolar bone crest is not correlated with skeletally sagittal or vertical parameters in females but negatively correlated with the skeletal sagittal parameter in males. In summary, different from the skeletal class II population, there is no significant difference in maxillary sinus size and location among different vertical skeletal patterns in the skeletal class I population. Compared to the skeletal class II population, a higher percentage of the skeletal class I population has an alveolar bone with less than 5 mm thickness, representing a narrowed safe zone of TADs placements.