Comparison of the pharyngeal airway in snoring and non-snoring patients based on the lateral cephalometric study: a case-control study

BACKGROUND: Normal airways are a key factor during the craniofacial growth of the young. Therefore, sleep-disordered breathing (SDB) without treatment can have harmful consequences for development and health. OBJECTIVES: This study aimed to evaluate the cephalometric characteristics in non-snoring individuals and snoring subjects, and investigate differences in the pharyngeal airway space between the 2 groups. MATERIAL AND METHODS: This case-control study included 70 patients aged over 18 years, selected from a radiology center. The patients were divided into 2 groups: case (35 patients with a history of habitual snoring); and control (35 healthy patients). The Berlin sleep questionnaire was administered to the parents of the patients. The nasopharyngeal airway was measured according to the analysis of Linder-Aronson (1970), and 4 indices were measured and analyzed in each of the lateral cephalometric radiographs. RESULTS: No statistically significant differences were observed in the pharyngeal measurements between the 2 groups, although all means in the control group were higher than in the experimental group. However, there was a significant relationship between gender and the Ba-S-PNS and PNS-AD2 indices. CONCLUSIONS: Although the patients with nocturnal snoring had smaller airway dimensions, their pharyngeal measurements were not significantly different from the control group

Dentin thickness of the danger zone in the mesial roots of the mandibular molars: a cone beam computed tomography analysis

BACKGROUND: Mandibular first molars appear to be the most commonly tooth subjected to a root canal treatment, therefore a better understanding of the anatomy critical zones for resistance of this teeth may decrease the treatment's failure rate. So, this study was conducted to evaluate the dentin thickness of the danger zone in mesial roots of mandibular first molars using cone beam computed tomography in an Iranian population. METHODS: In this cross-sectional study, 210 Cone Beam Computed Tomography acquisition of the mandibular first molars were collected from a radiology center in Qazvin. The dentin thickness of the mesial roots (mesiobuccal and mesiolingual canals) was measured from the furcation to 5 mm below. The relationship between the dentin thickness in the danger zone and parameters, like age, gender, placement side, root length, the curvature of the canal, canal type, presence of middle mesial canal, and distance between the orifices of the mesial canals was investigated. Frequency, mean and standard deviation for variables were calculated, and data analysis was done by SPSS using simple and multiple linear regression and Pearson correlation coefficient. Also, two-sample t-test was used to compare mesiobuccal and mesiolingual on two sides. The significant level was also considered at (p < 0.05). RESULTS: The average minimum thickness of danger zone dentin was found to be 0.885 ± 0.259 mm in the mesiobuccal canal and 0.906 ± 0.206 mm in the mesiolingualcanal. Also, the minimum thickness of dentin in the mesiobuccal and mesiolingual canals in the range of 0 to 1 mm from the furcation was more than in other areas. There was no significant relationship between the minimum dentin thickness of the danger zone with gender, placement side, root length, canal type, and mesial canal entrance distance. But with increasing age, the thickness of dentin in the danger zone in the mesiolingualcanal increased significantly (p = 0.008). It was also observed that with the increase in the curvature of the canal, the thickness of the dentin in the danger zone in the mesiobuccal canal decreased (moderately curved (p = 0.008), severely curved (p = 0.046)). In addition, the thickness of the dentin in the mesiobuccal and mesiolingual canal was less in the samples with the middle mesial canal (p = 0.047, 0.044). CONCLUSIONS: Less dentin thickness in the danger zone in the mesial roots of mesiolingual mandibular first molars was seen in younger patients in mesiolingual canal, with a greater degree of canal curvature in the mesiobuccal canal and teeth with a middle mesial canal. Therefore, it is suggested that large taper instruments should be used with more precision to prevent complications

Effect of premolar extraction and anchorage type for orthodontic space closure on upper airway dimensions and position of hyoid bone in adults: a retrospective cephalometric assessment

Background. This study aimed to assess the effect of premolar extraction and anchorage type for orthodontic space closure on upper airway dimensions and position of hyoid bone in adults by cephalometric assessment. Methods. This retrospective study was conducted on 142 cephalograms of patients who underwent orthodontic treatment with premolar extraction in four groups of (I) 40 class I patients with bimaxillary protrusion and maximum anchorage, (II) 40 class I patients with moderate crowding and anchorage, (III) 40 class II patients with maximum anchorage, and (IV) 22 skeletal class III patients with maximum anchorage. The dimensions of the nasopharynx, velopharynx, oropharynx, and hypopharynx, and hyoid bone position were assessed on pre- and postoperative lateral cephalograms using AudaxCeph v6.1.4.3951 software. Data were analyzed by the Chi-square test, paired t-test, and Pearson's correlation test (alpha D 0.05). Results. A significant reduction in oropharyngeal, velopharyngeal, and hypopharyngeal airway dimensions was noted in groups I, III, and IV (P <0:001), which was correlated with the magnitude of retraction of upper and lower incisors (r =0:6-0:8). In group II, a significant increase was observed in oropharyngeal and velopharyngeal dimensions (P < 0:001). A significant increase in nasopharyngeal dimensions occurred in all groups (P < 0:001). Also, in groups I and III, the position of hyoid bone changed downwards and backwards, which was correlated with reduction in airway dimensions (r =0:4-0:6). Conclusion. According to the present results, extraction orthodontic treatment affects upper airway dimensions and hyoid bone position. Maximum anchorage decreases airway dimensions while moderate anchorage increases airway dimensions

Forensic gender determination by using mandibular morphometric indices an Iranian population: a panoramic radiographic cross-sectional study

Gender determination is the first step in forensic identification, followed by age and height determination, which are both affected by gender. This study assessed the accuracy of gender estimation using mandibular morphometric indices on panoramic radiographs of an Iranian population. This retrospective study evaluated 290 panoramic radiographs (145 males and 145 females). The maximum and minimum ramus width, coronoid height, condylar height, antegonial angle, antegonial depth, gonial angle, and the superior border of mental foramen were bilaterally measured as well as bicondylar and bigonial breadths using Scanora Lite. Correlation of parameters with gender was analyzed by univariate, multiple, and best models. All indices except for gonial angle were significantly different between males and females and can be used for gender determination according to univariate model. Condylar height, coronoid height, and superior border of mental foramen and ramus were still significantly greater in males than in females after controlling for the effect of confounders (p < 0.05). Based on the best model, a formula including five indices of bicondylar breadth, condylar height, coronoid height, minimum ramus width, and superior border of mental foramen was used for gender determination. Values higher than 56% indicate male gender, while lower values indicate female gender, with 81.38% specificity for correct detection of females and 88.97% sensitivity for correct detection of males. Despite the satisfactory results, future research should focus on larger populations to verify the accuracy of the present findings

Relationship between posterior permanent dentition pattern and radiographic changes of the mandibular condyle

This study assessed the relationship between posterior permanent dentition and radiographic changes of the mandibular condyle. This descriptive, cross-sectional study was conducted on 300 panoramic radiographs of patients over 40 years of age (188 females and 112 males). Panoramic radiographs were evaluated for condylar changes such as flattening, subcortical sclerosis, subcortical cyst, erosion, osteophytes, and generalized sclerosis. Presence of muscle pain and temporomandibular joint (TMJ) pain and sounds, and history of TMJ trauma were also assessed. The occlusal scheme of posterior teeth was analyzed according to the Eichner’s index. The frequency of condylar changes was calculated in the right and left sides, and their association with posterior permanent dentition was analyzed by the Chi-square test (alpha = 0.05). The frequency of flattening, muscle pain, TMJ sounds, and erosion was 11.7%, 9.7%, 5.7%, and 3.7% in the right side, respectively. The frequency of flattening, muscle pain, erosion, and subcortical cyst was 12%, 9.3%, 5%, and 5% in the left side, respectively. The frequency of bilateral muscle pain, flattening, TMJ sounds, and TMJ pain was 18%, 16.7%, 11.7%, and 9.3%, respectively. Cases with TMJ trauma, generalized sclerosis, and osteophytes were few. According to the Eichner’s index, most patients with condylar changes had classes A and B, and a smaller percentage had class C. No significant difference was noted between healthy individuals and those with condylar changes regarding dentition patterns. No relationship existed between condylar changes and posterior permanent dentition pattern

Comparison of coronal discoloration induced by White MTA and CEM Cement

Coronal discoloration of endodontically treated teeth is a challenge in clinical dentistry. This study aimed to compare coronal discoloration induced by White Mineral Trioxide Aggregate and Calcium-enriched mixture cement. Fifty single-rooted, unrestored premolar teeth extracted for orthodontic reasons were selected. After access cavity preparation, all the root canals were instrumented with MTWO rotary files up to #40.6%. The specimens were randomly assigned to two experimental groups, White Mineral Trioxide Aggregate and Calcium-enriched mixture cement groups (n = 20), and two control groups (n = 5). In the White Mineral Trioxide Aggregate and Calcium-enriched mixture cement groups, the material was condensed via the access cavity 3 mm below the cementoenamel junction to a thickness of 3 mm. Tooth color was assessed using computer analysis of digital images. Tooth color measurements were recorded at eight time intervals: before material placement (but after tooth preparation), at 24 h, 48 h, one week, two weeks, four weeks, eight weeks, and sixteen weeks after material placement. Data were analyzed using t-test, ANOVA, repeated measure ANOVA, and Tukey HSD tests. The significance level was set at 5% for all the tests. Cervical discoloration of teeth in both experimental groups significantly increased over time (p < 0.05). However, samples in the White Mineral Trioxide Aggregate group showed more discoloration in cervical regions than Calcium-enriched mixture cement specimens after two, four, eight, and sixteen weeks (p < 0.05). Applying both White Mineral Trioxide Aggregate and Calcium-enriched mixture cement induced coronal discoloration; however, White Mineral Trioxide Aggregate samples exhibited greater cervical discoloration than Calcium-enriched mixture cement specimens after two, four, eight, and sixteen weeks

Salivary nitric oxide levels in adults with different DMFT scores in a selected iranian population: a cross-sectional study

Objectives: Due to the emphasis on the protective and antimicrobial role of Nitric Oxide against gas-trointestinal diseases, investigating its relationship with dental caries is a right topic. Therefore, this research has investigated the amount of saliva Nitric Oxide in different volumes of DMFT indicator in adults. Material and Methods: In this descriptive-analytical cross-sectional study, 80 participants (20-35 years old), without a history of systemic disease and drug use participated as research sam-ples, (53.8% of the participants in the study were women). Participants were selected from patients who had visited dental Department. The participants were divided in four groups based on DMFT (DMFT=0, 1≤DMFT≤3, 3<10, DMFT≥10). Non-stimulating saliva was collected from all participants between 9-11 am in a calibrated tube. Saliva Nitric Oxide was measured using a Nitrous Oxide test, based on the Griess reaction. We used a correlation test to analyze quantitative variables, and t-test or ANOVA for qualitative and quantitative variables. Results: A significant relationship between DMFT and age was identified. At different levels of DMFT, significant relationship between DMFT and sex was not found. In different groups of DMFT, no significant relationship between Nitric Oxide and DMFT exist. Conclusion: The level of Nitric Oxide saliva was not affected by the amount of DMFT

Comparison of the efficacy of NeoNiTi, ProTaper, and Reciproc files in the retreatment of curved root canals: a CBCT assessment

Objective: Effective tools and methods are applied during root canal retreatment to eliminate root canal obturation materials and preserve the initial root canal anatomy. The present study compared the efficacy of Reciproc, Neoniti, ProTaper, and Hedstrom files in the retreatment of curved root canals. Material and methods: In the present in vitro study, 100 root canals with 25‒45ºcurvatures were used. After the samples were initially prepared and examined by CBCT, the root canals were obturated with gutta-percha and randomly assigned to four groups (n=25). A retreatment was carried out in each group with NeoNiTi, ProTaper, Reciproc, and Hedstrom files. CBCT examinations were carried out again under the same conditions. The samples were evaluated at 3-, 6-, and 9-mm distances from the apex on the first and the second CBCT image for root canal transportation and remaining gutta-percha in the root canals. The time required for retreating each canal in each sample was recorded. One-way ANOVA and corresponding non-parametric tests were applied for data analysis. Results: The root canal transportation in the NeoNiTi group was lower than that in the other groups and significantly different from the ProTaper group (P<0.05). There was a remaining gutta-percha after re-treatments in all the four groups, which was not statistically significant (P>0.05). Conclusion: Despite the fact that the NeoNiTi file produced less transportation than other file systems evaluated in the retreatment of curved root canals, all the files were very effective at the clinically acceptable levels

Associations between fear of COVID-19, dental anxiety, and psychological distress among Iranian adolescents

Objectives: The present study evaluated the association of fear of COVID-19 with dental anxiety, oral health-related quality of life (OHRQoL), and psychological distress (depression, anxiety and stress), as well as exploring the mediating role of dental anxiety in the association of fear of COVID-19 with OHRQoL and psychological distress. Methods: A cross-sectional study was conducted among adolescents in high schools of Qazvin city (Iran) from March-June 2021, recruited through a two-stage cluster sampling method. All the adolescents completed a self-administered survey assessing (i) fear of COVID-19, (ii) depression, anxiety and stress, (iii) OHRQoL, and (iv) dental anxiety. Structural equation modelling was used to evaluate all the hypothesised associations, and the model fit was estimated. Results: A total of 2429 adolescents participated in the study. The conceptual model fitted the data well. Fear of COVID-19 had a direct effect on dental anxiety (B = 0.316; bias-corrected bootstrapping 95% CI = 0.282, 0.349), depression (B = 0.302; bias-corrected bootstrapping 95% CI = 0.259, 0.347), anxiety (B = 0.289; bias-corrected bootstrapping 95% CI = 0.246, 0.334), stress (B = 0.282; bias-corrected bootstrapping 95% CI = 0.237, 0.328), and OHRQoL (B = −0.354; bias-corrected bootstrapping 95% CI = −0.530, −0.183). Also, dental anxiety mediated the association of fear of COVID-19 with depression, anxiety stress, and OHRQoL. Conclusions: High levels of fear of COVID-19 were associated with high levels of dental anxiety and poorer OHRQoL. Moreover, fear of COVID-19 was positively associated with anxiety, depression and stress. Increased levels of dental anxiety were also associated with increased anxiety, stress, depression, and poorer OHRQoL

Medical image colorization for better visualization and segmentation

Medical images contain precious anatomical information for clinical procedures. Improved understanding of medical modality may contribute significantly in arena of medical image analysis. This paper investigates enhancement of monochromatic medical modality into colorized images. Improving the contrast of anatomical structures facilitates precise segmentation. The proposed framework starts with pre-processing to remove noise and improve edge information. Then colour information is embedded to each pixel of a subject image. A resulting image has a potential to portray better anatomical information than a conventional monochromatic image. To evaluate the performance of colorized medical modality, the structural similarity index and the peak signal to noise ratio are computed. Supremacy of proposed colorization is validated by segmentation experiments and compared with greyscale monochromatic images