Association among Orthodontic Malocclusions, Paranasal Sinuses Anatomic Variations and Adenoid Vegetation in Children Using CBCT.

The aim of this study is to evaluate the relationship between orthodontic malocclusion, paranasal sinus (PS) variations, and adenoid vegetation in a group of pediatric patients with chronic rhinosinusitis. Clinical and radiographical data were retrospectively evaluated and 58 patients were diagnosed as having chronic sinus disease. Cone-beam computed tomography (CBCT) images were acquired with Newtom-3G. Anatomical variations of the PS were assessed on every section. Additionally, for cephalometric analysis, the images were imported into the InVivoDental software program. A total of 252 anatomical variations, which encompassed 19 different types, were detected in the current study. Concha bullosa was the most common anatomical variation, at 72.4%. Septum deviation was the second most common one, at 67.2%. The Class III group exhibited a significantly higher prevalence of concha bullosa and secondary middle turbinate than the other groups. While adenoid vegetation was most common in the Class III group, sinusitis and antral disease were most common in the Class II group. Overall, Class III subjects exhibited fewer PS variations. In conclusion, concha bullosa emerged as the most prevalent anatomical variation, with distinctive patterns observed across different malocclusion groups. Therefore, CBCT is useful, especially in pediatric patients, due to its low dose advantage.

Evaluation of the influence of hyoid bone position, volume, and types on pharyngeal airway volume and cephalometric measurements.

OBJECTIVES: We aimed to explore the position, morphological, and morphometric properties of the hyoid bone (HB) and to investigate the effect of HB on the pharyngeal airway (PA) volume and cephalometric measurements. METHODS: A total of 305 patients with CT images were included in the study. DICOM images were transferred to the InVivoDental three-dimensional imaging software. The position of the HB was determined based on the cervical vertebra level and in volume render tab, the bone was classified into six types after all structures around the HB were removed. Also, final bone volume was recorded. In the same tab, the pharyngeal airway volume was divided and measured in three groups (nasopharynx-oropharynx-hypopharynx). The linear and angular measurements were performed on the 3D cephalometric analysis tab. RESULTS: HB was most commonly located in C3 vertebra level (80.3%). While B-type was found to be the most frequent (34%), V-type was the least frequent (8%). The volume of the HB was found to be significantly higher in male (3205 mm3) than female (2606 mm3) patients. Also, it was significantly higher in the C4 vertebra group. The vertical height of the face was positively correlated with the HB volume, C4 level position, and increased oro-nasopharyngeal airway volume. CONCLUSION: The volume of the HB is found to differ significantly between genders and can potentially serve as a valuable diagnostic tool for understanding respiratory disorders. Its morphometric features are associated with increased face height and airway volume; however, are not related with the skeletal malocclusion classes.

Comparison of hyoid bone morphology between obstructive sleep apnea patients and healthy individuals.

OBJECTIVE: We aimed to find morphological properties of the hyoid bone, which are predominant among the patients diagnosed with obstructive sleep apnoea (OSA), and compare them with healthy individuals. METHODS: A total of 67 cone-beam computed tomography (CBCT) image sequences of patients (44 males, 23 females) diagnosed with OSA and a total of 70 multislice computed tomography (MSCT) data of non-OSA patients (45 males, 25 females) were selected in this study. DICOM images were imported into InVivo 5.1.2 (Anatomage) software. The position of the hyoid bone relative to the C3 and C4 cervical vertebrae, as well as its morphological type (B, V, U, H, D, HK-type) and its total volume was determined. RESULTS: The volumetric values of the hyoid bone of OSA patients (2384.49 ± 682.073 mm3 ) were significantly (P < .001) lower compared to the values derived from non-OSA patients (2952.96 ± 932.5 mm3 ). The difference was independent of gender, and volumetric values showed a strong significant (P < .01) difference between male OSA and non-OSA (2709.18 ± 608.05; 3157.87 ± 926.5 mm3 ) and female OSA and non-OSA patients (1763 ± 242.51 2584; 2584.12 ± 840.21 mm3 ), as well. In the case of B and V-types, the volumetric values showed significant differences (P < .05), when the OSA (2300,77 ± 622; 2166 ± 312 mm3 ) and non-OSA patients were compared (2823,48 ± 780; 3216 ± 463 mm3 ). CONCLUSION: Our results suggest that the volume of the hyoid bone might be a potential biological marker for OSA, especially in the case of B and V hyoid bone types.

A deep learning algorithm proposal to automatic pharyngeal airway detection and segmentation on CBCT images.

OBJECTIVES: This study aims to evaluate an automatic segmentation algorithm for pharyngeal airway in cone-beam computed tomography (CBCT) images using a deep learning artificial intelligence (AI) system. SETTING AND SAMPLE POPULATION: Archives of the CBCT images were reviewed, and the data of 306 subjects with the pharyngeal airway were included in this retrospective study. MATERIAL AND METHODS: A machine learning algorithm, based on Convolutional Neural Network (CNN), did the segmentation of the pharyngeal airway on serial CBCT images. Semi-automatic software (ITK-SNAP) was used to manually generate the airway, and the results were compared with artificial intelligence. Dice similarity coefficient (DSC) and Intersection over Union (IoU) were used as the accuracy of segmentation in comparing the measurements of human measurements and artificial intelligence algorithms. RESULTS: The human observer found the average volume of the pharyngeal airway to be 18.08 cm3 and artificial intelligence to be 17.32 cm3 . For pharyngeal airway segmentation, a dice ratio of 0.919 and a weighted IoU of 0.993 is achieved. CONCLUSIONS: In this study, a successful AI algorithm that automatically segments the pharyngeal airway from CBCT images was created. It can be useful in the quick and easy calculation of pharyngeal airway volume from CBCT images for clinical application.

Comparing the effects of CAD/CAM nickel-titanium lingual retainers on teeth stability and periodontal health with conventional fixed and removable retainers: A randomized clinical trial.

OBJECTIVE: The objectives of this study were to evaluate the effect of a CAD/CAM nickel-titanium retainer on the stability of mandibular anterior teeth and periodontal health and to compare it with other retainers. SETTING/SAMPLE POPULATION: Sixty participants from both genders who had irregularities prior to orthodontic therapy and who had been treated with full-fixed appliance mechanotherapy were included in the study and randomly allocated into four groups: CAD/CAM NiTi, multi-stranded stainless steel, single-stranded nickel-free titanium and vacuum-formed removable retainer groups. The mean age of the participants at the end of the treatment was approximately 20 years. MATERIALS AND METHODS: Digital impressions were taken for all participants at three different times: immediately (T0 ), three months (T1 ) and six months (T2 ) after treatment. Irregularity index, inter-canine and inter-molar width, and arch length were recorded using software. Additionally, a full periodontal assessment was carried out at T2 . RESULTS: During the follow-ups, all groups showed some relapse in the lower anterior teeth. No statistical significance was found intergroup in terms of all measured values. Within the multi-stranded group, inter-canine width had decreased by 0.10 mm with a statistical significance (P = .048). An additional statistical significance with P = .045 was found within the single-stranded group regarding the increased arch length. The periodontal assessment results of the mandibular anterior teeth between groups did not show clinically significant differences. CONCLUSION: No statistical significance was found between the CAD/CAM retainer and other retainers regarding the clinical failure rate. Less plaque accumulation and gingival inflammation were observed in the CAD/CAM NiTi retainer group.

Effects of micro-osteoperforations on intraoral miniscrew anchored maxillary molar distalization : A randomized clinical trial.

PURPOSE: The aim was to study the effects of micro-osteoperforations (MOPs) on miniscrew-supported maxillary molar distalization. METHODS: As part of a single center, split-mouth, randomized clinical trial, 20 eligible subjects were randomly recruited from patients who had applied to the orthodontics department of a university dental hospital. In the experimental group, subjects were randomized to receive MOPs to either the left or right maxillary molar region (n = 10). The control group (n = 10) and the contralateral sides of the experimental group (n = 10) did not receive any MOPs. In both groups, distalization of the maxillary molars was performed by miniscrew-supported distalization appliances. Using 3D models, maxillary molar distalization at 3, 6, 9, and 12 weeks was measured. Pain, discomfort, eating difficulty, and speech problem levels were assessed using a visual analog scale (VAS 0-10). Periodontal evaluations were performed. RESULTS: In all, 18 subjects completed the study. The mean amount of tooth movement was significantly greater on the MOP side compared to contralateral side of the experimental group at all time points. After 12 weeks, the maxillary molars on the MOP side moved 1.17-fold more than those on the contralateral side. No significant differences were found regarding amount of tooth movement between the control group and the MOP and contralateral sides of the experimental group. The rates of tooth movement in the MOP sides of the experimental group, contralateral sides of the experimental group, and the control group were 0.029, 0.025, and 0.028 mm/day, respectively. Pain VAS scores after intervention were significantly increased on the MOP side compared with the contralateral side of the experimental group but not at any other time point. No differences in periodontal scores between the groups were observed. CONCLUSIONS: A 1.17-fold increase in the rate of tooth movement in the MOP group compared with the contralateral side was recorded. However the accelerating effect of MOPs was lower than expected. The mean pain level was statistically greater in the MOP group compared to the contralateral side only on the first day of application.

Comparison of anterior mandible anatomical characteristics between obstructive sleep apnea patients and healthy individuals: a combined cone beam computed tomography and polysomnographic study.

PURPOSE: This study aims to evaluate the morphology of the genial tubercle (GT) and lingual foramen (LF) between obstructive sleep apnea (OSA) and non-OSA patients for considerations of mandibular advancement surgery. METHODS: Cone beam CT records of 198 patients were retrospectively collected and analyzed. Five variables were measured for genial tubercle; anterior mandible thickness (AMT), the distance from the lower incisors to the superior border of the genial tubercle, the distance from the inferior border of the genial tubercle to inferior border of the mandible, the height of GT, and genial tubercle width. Lingual foramen were classified according to the genial tubercle. The frequencies, distances of lingual foramen to alveolar crest, lower border of mandible (LVDL) and diameter of LF were also measured. RESULTS: Significant differences was found for genial tubercle width, anterior mandible thickness, and the distance of lower mandibular border to the midline lingual foramina between OSA and non-OSA patients (p < 0.05). AMT gets thicker and GT gets narrower in OSA patients (p < 0.05). A linear regression analysis on the apnea hypopnea index with measured anatomical variables showed the LVDL (R = - 0.355*), body mass index (R = 0.254), and age (R = 0.33) showed a statistically significant association (p < 0.05). None of the other variables reached formal significance. CONCLUSION: LVDL is linearly associated with sleep apnea severity. The variable dimensions and anatomy of genial tubercle as well as lingual foramen for OSA patients suggest the need of 3D preoperative radiological evaluation before genioglossus advancement surgery. Cone beam CT can be a powerful low radiation dose tool both for evaluating the anatomy of the upper airway and mandibular structures at the same time for OSA patients.

Novel application and validation of in vivo micro-CT to study bone modelling in 3D.

OBJECTIVES: The aim is to highlight a novel three-dimensional (3D) imaging methodology using micro-CT scans to visualize and measure bone modelling in an animal model. In order to validate the new methodology, we compared the 3D imaging method to traditional two-dimensional (2D) histomorphometry to assess growth changes in the jaws of a rodent. SETTING AND SAMPLE POPULATION: Rodent animal models. MATERIAL AND METHODS: Eleven rats were obtained from a larger previously published study. Sixty undecalcified histological sections from the maxilla and corresponding high-resolution in vivo micro-CT reconstructions were obtained. Bone modelling changes on specific alveolar surfaces were measured using traditional histomorphometry. Measurements of bone growth were also obtained via 3D Slicer software from 3D micro-CT generated models from the same plane containing the histological images. Both qualitative and quantitative 3D methods were compared to traditional histological measurements. Quantitative agreement between methods was categorized as follows: poor (>150 µm), good (150-100 µm) and excellent (<100 µm). RESULTS: Both qualitative (88.3%) and quantitative (86.7%) 3D measurements showed excellent agreement, when compared to histomorphometric measurements. Only 1.7% and 5% of the comparisons exhibited poor agreement (>150 µm) for qualitative and quantitative methods, respectively. DISCUSSION: The new 3D superimposition method compares very favourably with traditional histology. It is likely that in the future, such methods will be used in studies of bone adaptation. CONCLUSION: The 3D micro-CT qualitative and quantitative methods are reliable for measuring bone modelling changes and compare favourably to histology for the specific application described.

Influence of mini-screw diameter and loading conditions on static and dynamic assessments of bone-implant contact: An animal study.

OBJECTIVES: The goal was to compare static versus dynamic bone-implant interface histology of mini-screws and to evaluate its relation to diameter and load. SETTING AND SAMPLE POPULATION: Canine animal model. MATERIAL AND METHODS: Custom-machined, titanium alloy (Ti6AI4V) mini-screws (n = 70) of 1.60, 2.00, 3.00 and 3.75 mm diameter were placed into edentulous sites in five skeletally mature beagle dogs. Using a split-mouth design, no load (NL) was applied to one side while a 2N load (L) was applied by calibrated coil springs on the other side. Intravenous bone labels were administered 21 and 7 days prior to sacrifice. Dogs were euthanized 90 days after screw placement. Bone sections were analysed under bright-field and epifluorescent light. The region of interest was defined as the bone within the threads of the screws. The following parameters were quantified: (a) Static-bone volume/tissue volume (BV/TV %) and bone-implant contact (BIC, %); (b) Dynamic-labelled bone/bone volume (LB/BV, %), and dynamic BIC (DBIC, %). RESULTS: BV/TV ranged from 71.2% to 85.0% of the screw surface. BIC ranged from 45.7% to 55.4% of the screw surface and was not affected by diameter (P = 0.66). In contrast, the percentage of DBIC did not vary with the applied load (P = 0.41); however, it correlated significantly with the diameter of the screw (P = 0.001). CONCLUSION: The percentage of DBIC that is actively remodelling increases with increasing diameter of the screw. Dynamic histomorphometry is more sensitive to detecting changes in bone-implant contact when compared to static measurements.

Screw-type device diameter and orthodontic loading influence adjacent bone remodeling.

OBJECTIVE: To evaluate the effect of diameter and orthodontic loading of a screw-type implantable device on bone remodeling. MATERIALS AND METHODS: Screw-shaped devices of four distinct diameters, 1.6, 2, 3, and 3.75 mm, were placed into edentulous sites in five skeletally mature beagle dogs (n = 14/dog) following premolar extraction. Using a split-mouth design, devices on one side were loaded using calibrated 2N coil springs. Epifluorescent bone labels were administered intravenous prior to sacrifice. Bone-implant sections (∼ 70 µm) were evaluated to quantify bone formation rate (BFR), and other histomorphometric variables were assessed in the implant supporting bone. RESULTS: The mean BFR ranged from 10.93 percent per year to 38.91 percent per year. BFR in the bone adjacent to the device was lower for the loaded 1.6-mm screws when compared with the nonloaded 1.6-mm screws (P < .01) and the loaded 2.0-, 3.0-, and 3.75-mm diameter screws (P < .01). No significant differences in BFR were noted, regardless of loading condition, between the 2.0-, 3.0-, and 3.75-mm diameter screws. CONCLUSIONS: We detected a dramatic reduction in bone remodeling. Although orthodontic loading of 2N did not alter bone remodeling associated with screws with a 2.0-mm diameter or larger, it did decrease bone remodeling adjacent to a loaded 1.6-mm screw. The long-term effect of this diminished remodeling should be further investigated.

Three-dimensional cephalometric norms of Turkish Cypriots using CBCTimages reconstructed from a volumetric rendering program in vivo.

BACKGROUND/AIM: The aim of this study was to create a database of 3D cephalometric measurements of Turkish Cypriot patients using a 3D rendering software program. MATERIALS AND METHODS: The study population comprised 121 subjects who had undergone cone beam CT imaging (CBCT). Invivo 5.1 software was used to generate cephalograms from the CBCT dataset that were then linked to the 3D hard-tissue surface representations. In total, 38 angular and 28 linear widely used measurements were recorded. RESULTS: The results demonstrated that males had significantly larger mean values than females for all linear measurements, except for dentoalveolar parameters (P < 0.05). Additionally, significant differences were found in most of the mandibular anteroposterior and vertical measurements, especially SNB, GoGn/SN, FMA, and MP/SN, between the sexes (P < 0.05). CONCLUSION: This is the first population-based study to focus solely on Turkish Cypriots' craniofacial anatomy and orthodontic characteristics. The present findings will produce 3D cephalometric normative data for the Cypriot population and will be valuable for oral and maxillofacial surgeons and orthodontists in Cyprus, the UK, Australia, Turkey, and other European countries who treat a large number of Turkish Cypriot patients.

Association between pterygoid hamulus length and apnea hypopnea index in patients with obstructive sleep apnea: a combined three-dimensional cone beam computed tomography and polysomnographic study.

OBJECTIVE: The purpose of this study was to investigate the relationships among the pterygoid hamulus (PH), the maxillo-mandibular complex to the pharynx, the upper airway, and the soft palate and a possible connection to sleep apnea severity as assessed by polysomnography. STUDY DESIGN: A total of 100 left and right sides of the PH were retrospectively measured by two observers from 50 cone beam computed tomography images by using three-dimensional rendering program in patients with obstructive sleep apnea (33 males and 17 females, with a mean age of 56.8 years; range 32-82 years). RESULTS: The mean apnea hypopnea index was 30.2 (range 0-95). A linear regression analysis on the apnea hypopnea index with the total length of the PH adjusted for gender, body mass index, neck circumference, and age showed a statistically significant association: (-0.234(∗); P = .005). None of the other variables reached formal significance. CONCLUSION: The pterygoid hamulus length is inversely associated with sleep apnea severity. Our study provides further insight into the pathophysiology of sleep apnea, with the result that PH length could be a future supplementary measurement to help clinicians to stratify and determine the best treatment options for patients with obstructive sleep apnea.

A multi-centre evaluation of multiple supernumerary premolar prevalence.

AIM: The occurrence of multiple supernumerary teeth is rare and often found in association with syndromes such as cleidocranial dysplasia, Gardner's syndrome or cleft lip and palate. Few examples of non-syndromal multiple supernumerary teeth have been reported. The aim of this multi-centre study was to investigate the prevalence of supernumerary premolar teeth in non-syndromic patients and to investigate the association between the presence of supernumerary premolar teeth and malocclusion type in a Turkish population. MATERIALS AND METHODS: The clinical records and panoramic radiographs of 10,700 patients (referred to three different university hospitals) were retrospectively examined for the presence of supernumerary premolars. Age, gender, orthodontic malocclusion type, the number of supernumerary premolars (two or more), the distribution, location, position (vertical, horizontal, inverted, mesio-angular), surgical approach, and related complications (pain, cystic changes, root resorption, or eruption disturbance of adjacent teeth) were recorded. RESULTS: Forty-two cases (13 Class I, 17 Class II, 12 Class III) of multiple mandibular supernumerary premolars in patients without an associated syndrome were detected. A total of 97 (27 Class I, 41 Class II, 29 Class III) supernumerary premolar teeth were found, with a prevalence of 0.39%. No statistical difference was found related to gender, malocclusion type and supernumerary premolars (p > 0.05). The majority of the extra premolars were located in the mandible, which was statistically significant (p < 0.05). CONCLUSION: The present study revealed that the prevalence of multiple supernumerary teeth was 0.39%. The most frequently impacted premolars were found in the mandible and more often associated with Class II malocclusions in the examined Turkish population.

Interdisciplinary approach to oral rehabilitation of patient with amelogenesis imperfecta.

Amelogenesis imperfecta is a hereditary condition that affects the development of enamel, causing quantity, structural and compositional anomalies that involve all dentitions. Consequently, the effects can extend to both the primary and secondary dentitions. Patients with amelogenesis imperfecta may present with clinical difficulties, such as insufficient crown length, tooth sensitivity and orthodontic discrepancies, all of which can be resolved successfully with an interdisciplinary approach. This case report describes the interdisciplinary approach to the treatment of a 22-year-old patient with amelogenesis imperfecta. The proper alignment of anterior teeth and gingivo-cervical line was provided with orthodontic and periodontal treatments. All-ceramic crowns were placed on anterior, and metal-ceramic restorations were placed on posterior teeth to reduce sensitivity and improve esthetics with function. Improved esthetic appearance, reduced tooth sensitivity and the resolution of a potentially harmful psychosocial condition were achieved. Patient remained satisfied in the 12-month follow-up examination.

Two-dimensional lateral cephalometric evaluation of varying types of Class II subgroups on posterior airway space in postadolescent girls: a pilot study.

AIMS: The purpose of this study was to compare pharyngeal airway linear measurements of untreated skeletal Class II subjects with low-, neutral- and high-angle facial patterns and a skeletal Class I control group of postadolescent girls. METHODS: We enrolled 50 postadolescent girls in this study. The Class II,1 cohort included subjects presenting ANB angles greater than 4°. Subjects were categorized as belonging to one of three different rotation models: high, neutral and low angles. ANOVA and Duncan's tests were used to identify differences within and among groups (p<0.05). RESULTS: Pharyngeal airway measurements were significantly smaller (p<0.05) in the high-angle Class II group. In addition, the narrowest linear measurements of the oropharynx (ph-pph) were also smaller in the high-angle Class II group (p=0.055). Soft palate thickness (sp1-sp2) was significantly greater (p<0.05) in the low-angle Class II group. CONCLUSION: That smaller airway measurements in only the high-angle Class II subjects were noted confirms an association between pharyngeal airway measurements and a vertical skeletal pattern. However, we could not ascertain that a sagittal jaw relationship had an effect on airway space.

Evaluation of the pterygoid hamulus morphology using cone beam computed tomography.

OBJECTIVE: This study consists of anatomic research of the pterygoid hamulus (PH) using 3D cone beam computed tomography (CBCT) images reconstructed from a volumetric rendering program. STUDY DESIGN: Three hundred ninety-six sides in the CBCT scans of 198 (115 men and 83 women) patients were retrospectively analyzed. DICOM data of the patients were transferred to a surface-rendering software so as to generate 3D hard tissue surface representations of PHs. The width, length, angle, and the distance between posterior nasal spine and tip of the PH were measured. In addition, the inclinations of PHs were also evaluated in sagittal and coronal planes of the 3D images. Pearson χ(2) and Student t test were performed for statistical analysis among age, localization, and measurements (P < .05). RESULTS: The mean PH measurements of left and right sides were 1.72 (SD 0.94) and 1.87 (SD 1.17)-mm width, and the lengths were 5.48 (AD 1.94), and 5.40 (SD 2.0) mm, respectively, with no significant difference (P > .05). All PHs were inclined toward the lateral side in the coronal plane, whereas PHs tended to incline toward the posterior rather than anterior in the sagittal plane (∼78%). The results showed no statistically significant differences among age, localization, and measurements of PHs (P > .05). CONCLUSIONS: Knowledge about the morphology of these structures is helpful for the interpretation of imaging and provides valuable information in the differential diagnosis of untraceable pains in the oral cavity and pharynx. Because of potential problems owing to PH morphology and elongation, oral and maxillofacial radiologists should assess the radiographic images thoroughly.

Misdiagnosed fibrosarcoma of the mandible mimicking temporomandibular disorder: a rare condition.

The jawbones can be sites of various neoplastic conditions. Given the variety of processes affecting this particular anatomical area, formulation of a precise diagnosis can be challenging to clinicians. Limited jaw movement, pain, and facial asymmetry are common signs among patients, especially those with temporomandibular disorder (TMD). This paper reports a case of primary fibrosarcoma affecting the mandible and surrounding structures in a 14-year-old girl presenting signs and symptoms similar to TMD. Her condition was misdiagnosed, and she was treated for TMD over an extended period before the correct diagnosis was made for fibrosarcoma. The patient underwent surgical resection with postsurgical radiotherapy and chemotherapy and now is being followed up. Although malignant lesions are rare in the temporomandibular joint (TMJ) region, dentists are advised to be aware of the condition and to keep in mind that patients who are admitting for TMD can also possibly be affected from neoplasms. Hence, those patients have to be examined meticulously to avoid misdiagnosis and mistreatment.