The role of vitamin D in outcomes of critical care in COVID-19 patients: evidence from an umbrella meta-analysis of interventional and observational studies.

OBJECTIVES: Several meta-analyses have suggested the beneficial effect of vitamin D on patients infected with severe acute respiratory syndrome coronavirus-2. This umbrella meta-analysis aims to evaluate influence of vitamin D supplementation on clinical outcomes and the mortality rate of COVID-19 patients. DESIGN: Present study was designed as an umbrella meta-analysis. The following international databases were systematically searched till March 2023: Web of Science, PubMed, Scopus, and Embase. SETTINGS: Random-effects model was employed to perform meta-analysis. Using AMSTAR critical evaluation tools, the methodological quality of the included meta-analyses was evaluated. PARTICIPANTS: Adult patients suffering from COVID-19 were studied. RESULTS: Overall, 13 meta-analyses summarising data from 4 randomised controlled trial and 9 observational studies were identified in this umbrella review. Our findings revealed that vitamin D supplementation and status significantly reduced mortality of COVID-19 [Interventional studies: (ES = 0·42; 95 % CI: 0·10, 0·75, P < 0·001; I2 = 20·4 %, P = 0·285) and observational studies (ES = 1·99; 95 % CI: 1·37, 2·62, P < 0·001; I2 = 00·0 %, P = 0·944). Also, vitamin D deficiency increased the risk of infection and disease severity among patients. CONCLUSION: Overall, vitamin D status is a critical factor influencing the mortality rate, disease severity, admission to intensive care unit and being detached from mechanical ventilation. It is vital to monitor the vitamin D status in all patients with critical conditions including COVID patients.

Three-dimensional evaluation of mandibular lingula: Comparisons of skeletal angle classifications and growth patterns.

OBJECTIVES: This study aimed to evaluate the position of the mandibular lingula (ML) in adult patients (aged between 18 and 35 years old) with different skeletal and growth patterns using cone-beam computed tomography (CBCT). DESIGN: Cross-sectional. SETTING: Dentistry department of University. SUBJECTS: Subjects comprised CBCT images of 150 adult patients, including 300 rami. METHODS AND MATERIALS: In total, 150 CBCT aged between 18 and 35 were selected and divided into three main groups of 50 samples based on their skeletal relationships (classes I, II and III). Patients were subdivided based on their growth pattern (vertical vs. horizontal), resulting in 25 samples per subgroup. Distances between the mandibular lingula and occlusal plane (ML-OP), sigmoid notch (ML-SN), external oblique ridge (ML-EOR), internal oblique ridge (ML-IOR), posterior border of the ramus (ML-PBR), inferior border of the ramus (ML-IBR), and horizontal and vertical distances to the mandibular foramen (ML-hMF and ML-vMF). One-way ANOVA variance analysis was employed to compare different angle classifications, and Bonferroni analysis was used for multiple comparisons. The Student's t-test was also used to compare growth patterns within each main group and genders within the subgroup. RESULTS: The study revealed statistically significant differences in the position of the mandibular lingula between different angle classifications, growth patterns, and genders. Class II samples showed a more anterior position of the ML, whereas Class III samples displayed a more posterior position of the ML. Patients with horizontal growth patterns and Angle Class III had a more posteriorly positioned ML. Gender differences were observed, particularly in Class I and Class III classifications, suggesting that gender may influence the variability of ML position in these specific classifications. CONCLUSION: The position of the mandibular lingula showed high variability among individuals with different angle classifications, growth patterns and genders.

The effect of Alexander, Gianelly, Roth, and MBT bracket systems on anterior retraction: a 3-dimensional finite element study.

OBJECTIVES: The aims of this study were to compare the effect of 4 bracket systems including Alexander, Roth, MBT, and Gianelly on upper anterior retraction and to quantify the amount of torque loss ratio in sliding mechanics by help of a 3-dimensional (3D) finite element method. METHOD AND MATERIALS: 3D FEM models were constructed in order to simulate anterior incisor retraction in first premolar extraction case. Displacement, stress, and strain on the incisal edge and apex of maxillary central incisor were calculated when 1-, 2-, and 3-N retraction forces were applied. Torque loss ratio was calculated by measuring the displacement of the teeth at crown tip and root apex in all 4 bracket systems on upper central incisor. RESULTS: Uncontrolled lingual crown tipping of the incisor was observed in all bracket systems. The crown moved lingually by 9.5 µm and the root labially by 4.5 µm in MBT system with 3-N retraction force. The amount of crown movement was 8 µm and the root displacement was 4 µm in Gianelly system with the same retraction force. Torque loss ratio was 1.46 in Alexander and Gianelly with 3-N retraction force. However, the amount of torque loss ratio was 1.47 in MBT and Roth with the same retraction force. CONCLUSIONS AND CLINICAL RELEVANCE: Uncontrolled tipping was the least in Gianelly and was the highest in MBT. The amount of torque loss ratio was the lowest in Gianelly and Alexander systems and the amount of torque loss ratio was the highest in MBT system.

In vivo confocal microscopy analysis of enamel defects after orthodontic treatment: A preliminary study.

After orthodontic treatment with fixed appliances, bonded brackets and residual adhesive must be removed. This procedure should lead to restitutio ad integrum of the enamel or, at least, restore the enamel surface as closely as possible to its pre-treatment conditions. The purpose of this study is the in vivo assessment at a microscopic resolution of enamel surfaces after bracket debonding while avoiding the tooth extraction. Nine orthodontic patients who had brackets removed at the conclusion of orthodontic treatment were enrolled. In vivo reflectance confocal microscopy imaging of dental enamel surface after debonding was performed for each patient. Eighteen upper incisors were analyzed, 10 in which the enamel demineralization appeared after the treatment and 8 in which the demineralization was present before the treatment. RCM analyses showed some speckled or roundish dark areas within the enamel. Moreover enamel alterations were detected at different levels of depth. The present in vivo microscopic study allowed for highlighting structural features in dental enamel, after debonding, at a microscopic resolution in real-time and in a non-invasive way, without the need for extraction or processing of the samples.

Methodological quality and outcome of systematic reviews reporting on orthopaedic treatment for class III malocclusion: Overview of systematic reviews.

OBJECTIVES: The aim of this overview of systematic reviews was to investigate methodological quality and outcome of current systematic reviews (SRs) reporting on orthopaedic treatment for class III malocclusion. MATERIALS AND METHODS: Computerized and manual searches were performed in Medline, Google Scholar, Cochrane Library, Embase, LILACS, SciELO, American Journal of Orthodontics and Dentofacial Orthopaedics, Angle Orthodontist, European Journal of Orthodontics, Journal of Orthodontics, Conference abstracts and Grey literature. No restrictions were set on language or date of publication. The search covered the starting date of the relevant databases until 30 April 2015. MeSH terms and free-text terms included 'malocclusion', 'Angle class III', 'orthodontic appliances', 'functional', facemask, review and meta-analysis. Screening of eligible studies, assessment of the methodological quality of the SRs and data extraction were conducted in duplicate and independently by two reviewers. Methodological quality was assessed using AMSTAR (assessment of multiple systematic reviews). RESULTS: A total of 222 studies were retrieved and after removal of duplicates, irrelevant studies, literature reviews and surgical approach treatments, 14 SRs and/or meta-analyses were included for qualitative synthesis. Mean AMSTAR score was 7.7/11 with a range of 3-10. There was evidence to demonstrate that face mask therapy can move the maxilla forward whilst causing a backward rotation of the mandible and increased facial height. There was also some evidence of mandibular growth retardation with chin cup therapy. CONCLUSIONS: Orthopaedic appliances can improve a class III malocclusion in growing patients over the short-term; however, each appliance has a characteristic effect on the underlying skeletal pattern.

Photogrammetric analysis of facial profile in Persian adults.

When facial photographs are analyzed for the purpose of identifying esthetics norms, differences in dentofacial relationships among ethnic and racial groups must be taken into consideration. Therefore, it is necessary to establish standards for various populations. The purpose of this study was to establish norms of photogrammetric soft tissue profile analysis for Persian adults. Pretreatment lateral photographs of 147 subjects (66 men and 81 women aged 18-35 years) with a Class I skeletal pattern were collected. Twelve angular parameters were evaluated in the subjects. Values for men and women were compared with a t test. Statistically significant sexual dimorphism was found for nasofrontal (P < 0.059), nasal (P < 0.059), nasal dorsum (P < 0.001), cervicomental (P < 0.001), facial convexity (P < 0.004), and total facial convexity (P < 0.002) angles. The mean values obtained from this study can assist in orthodontic diagnosis and treatment planning for Persian adults.

Hypodontia and supernumerary and impacted teeth in children with various types of clefts.

INTRODUCTION: The purpose of this study was to determine the prevalence of hypodontia, hyperdontia, and impacted teeth in children with various types of clefts. METHODS: This study sample consisted of 201 cleft patients including 131 male subjects with a mean age of 12.3 ± 4 years and 70 female subjects with a mean age of 12.6 ± 3.9 years. Charts, models, radiographs, and intraoral photographs were used for the study. t tests, chi-square tests, and binomial tests were used for assessment of the data. RESULTS AND CONCLUSIONS: Hypodontia was found in 129 subjects (64.1%). The chi-square test showed no statistically significant difference between the type of cleft and hypodontia (P <0.319). The binomial test showed that the frequencies of subjects with hypodontia were significantly higher in both unilateral and bilateral cleft lip and palate patients (P <0.015 and P <0.001, respectively). Hyperdontia and impacted teeth were also found to occur mostly in the maxillary arch, and maxillary canines were the most commonly impacted teeth in both unilateral and bilateral cleft lip and palate patients.

Finite element analysis of miniscrew placement in mandibular alveolar bone with varied angulations.

SUMMARY BACKGROUND: Titanium miniscrews are increasingly used as orthodontic anchorage. Various factors are known to affect the stability of miniscrew. Placement angle is one of the most controversial issues in this area. Thus, the aim of this finite element study was to evaluate the influence of placement angle and direction of force on the stability of miniscrews. MATERIALS AND METHODS: Finite element analysis was performed using miniscrews inserted into 1mm of cortical bone and 10mm of trabecular bone at angles of 30, 60, 90, 120, and 150 degrees to the alveolar bone. Force of 2 Newton (N) was applied to the heads of the miniscrews in two directions of 0 and 30 degrees. RESULTS: The finite element analysis showed that inserting miniscrews at 90 degree angle would provide better anchorage than 30, 60, 120, and 150 degree angles at either direction of force. The least trabecular bone von Mises stress was 5.6MPa at 90 degrees at both directions of force and the least cortical bone stress was 31.2MPa at 90 degrees at both directions of force. CONCLUSIONS: Insertion of miniscrews at angles less than or greater than 90 degrees to the alveolar process bone might decrease the anchorage stability of the miniscrew.

The short-term effects of face mask and fixed tongue appliance on maxillary deficiency in growing patients--a randomized clinical trial.

BACKGROUND: The purpose of this single blind, prospective, parallel randomized trial study was to compare the effects of face mask and fixed tongue appliance in treatment of Class III malocclusion with maxillary deficiency in growing patients. METHODS: 88 patients with maxillary deficiency were selected. 60 fulfilled the study requirements. The patients were randomly assigned to 2 groups by computer generated tables. One group was treated with removable face mask and the other group was treated by fixed tongue appliance. 4 of the patients dropped out of study leaving a final number of 56 patients. Thus, the face mask group included 30 patients (13 males, 17 females) with the mean age of 8.5 (SD 1.4) years and the fixed tongue appliance group included 26 patients (13 males, 13 females) with the mean age of 8.9 (SD 1.7) years. The patients Lateral cephalograms obtained at the beginning and end of the study were analyzed. RESULTS: Paired t-tests showed that SNA increased by 1.3° (SD 1.1°) in face mask group (P<0.001) and it increased by 1.8° (SD 0.9°) in fixed tongue appliance group (P<0.001). T-test showed that there were no statistically significant differences between the two groups except for SNB. IMPA decreased significantly in both groups. CONCLUSIONS: Both treatment modalities were successful in moving the maxilla forward and improving the profile of the patients; however, the bulky size of face masks might reduce patients' compliance and make them less favorite choice of treatment.

Therapeutic effects of local application of dexamethasone during bilateral sagittal split ramus osteotomy surgery.

PURPOSE: Bilateral sagittal split ramus osteotomy (BSSO) is one of the most common procedures used in the treatment of mandibular deformity. One common complication of this surgical procedure is hypoesthesia of the inferior alveolar nerve. The authors hypothesized that perioperative local application of dexamethasone would have positive therapeutic effects on neurosensory function. MATERIALS AND METHODS: This study investigated 18 patients (10 male, 8 female; mean age, 26.1 ± 4.9 yr) who underwent BSSO. One side of each patient's mandible was randomly selected as the control side and the opposite side as the experimental side. A solution of dexamethasone 4 mg/1 mL was drawn into a syringe and poured directly on the distal segment of the exposed inferior alveolar nerve during splitting and 1 mL was poured on the same nerve immediately before the start of fixation. Neurosensory tests, including light touch, direction of movement, static 2-point touch, thermal stimuli, and pin prick discrimination, were conducted. The χ(2) and Fisher exact tests were used to evaluate the data. RESULTS: The difference between the control and experimental groups at all intervals was not significant for any of the neurosensory tests. CONCLUSION: Local application of dexamethasone on the exposed inferior alveolar nerve during BSSO is not recommended.

The relationship between frenulum length and malocclusion.

This study sought to evaluate the relationship between the length of lingual frenula and various classes of malocclusion. One hundred-fifty patients who had been referred for orthodontic treatment were divided into 3 groups (n = 50) based on their lingual frenula ANB (Point A, nasion, point B) angle: Group 1 (ANB angle = 0-4 degrees), Group 2 (ANB angle >4 degrees), and Group 3 (ANB angle <0 degrees). The mean frenulum length for Group 1 subjects was 11.4 (±3.0) mm, compared to 9.5 (±3.5) mm for Group 2 subjects, and 14 (±3.0) for Group 3 subjects. According to 1-way ANOVA testing, these differences were statistically significant (P < 0.001). In addition, maximum mouth opening was also significantly greater for the Group 3 subjects (P < 0.001).

Comparison of nickel and chromium ions released from stainless steel and NiTi wires after immersion in Oral B®, Orthokin® and artificial saliva.

AIM: Oral environment of the mouth is a suitable place for biodegradation of alloys used in orthodontic wires. The toxicity of these alloys namely nickel and chromium has concerned the researchers about the release of these ions from orthodontic wires and brackets. The aim of this study was to measure the levels of nickel and chromium ions released from 0.018" stainless steel (SS) and NiTi wires after immersion in three solutions. MATERIALS AND METHODS: One hundred and forty-four round NiTi and 144 round SS archwires with the diameters of 0.018" were immersed in Oral B®, Orthokin® and artificial saliva. The amounts of nickel and chromium ions released were measured after 1, 6, 24 hours and 7 days. RESULTS: Two way repeated ANOVA showed that the amount of chromium and nickel significantly increased in all solutions during all time intervals (p < 0.002). CONCLUSION: Chromium and nickel ions were released more in NiTi wire in all solutions compared with SS wire. The lowest increase rate was also seen in artificial saliva. CLINICAL SIGNIFICANCE: There is general consensus in literature that even very little amounts of nickel and chromium are dangerous for human body specially when absorbed orally; therefore, knowing the precise amount of these ions released from different wires when immersed in different mouthwashes is of high priority.

Effects of Twin-Block and Faramand-LL appliances on soft tissue profile in the treatment of Class II division 1 malocclusion.

Individuals with class II division I malocclusion suffer from increased over jet and unpleasant facial profile which induce poor self-image and low self-esteem. Mechanisms of different orthopedic appliances correcting class II malocclusion are investigated in numerous studies. Most of these researches focused on only the dentofacial changes and ignored the alterations of soft tissue profile. Evaluation of soft tissue alterations in patients treated with Faramand-II and Tween-Block appliances were the purposes of this study.

The effect of vitamin D2 supplementation on vitamin D levels in humans: A time and dose-response meta-analysis of randomized controlled trials.

BACKGROUND: Inconsistencies exist regarding the influence of vitamin D2 (ergocalciferol) supplementation on serum vitamin D levels. These inconsistencies could be attributed to numerous factors, such as dosage, baseline vitamin D levels, and duration of intervention. Hence, this dose-response meta-analysis of randomized controlled trials was conducted to assess the efficacy of vitamin D2 supplementation on vitamin D levels. METHODS: Relevant studies were searched in PubMed/Medline, Web of Science, Embase, and Scopus, from their inception to 3 January 2023. Variable alterations were considered to calculate the pooled weighted mean difference (WMD) with 95% confidence interval (CI) using the random effects model. RESULTS: Pooled results from 33 study arms demonstrated that Vitamin D2 treatment significantly increases total vitamin D concentrations (WMD: 11.47 ng/mL, 95 %CI: 9.29 to 13.64, p < 0.001), 25(OH)D2 concentrations (WMD: 11.40 ng/mL, 95 %CI: 4.72 to 18.09, p = 0.001), and 1,25(OH)D concentrations (WMD: 5.61 ng/mL, 95 %CI: 0.74 to 10.48, p = 0.024), but decreases 25(OH)D3 concentrations (WMD: -4.63 ng/mL, 95 %CI: -6.46 to -2.81, p < 0.001). In subgroup analyses, increase in total vitamin D concentrations was more significant in vitamin D2 doses >2000 IU/day (WMD: 13.82 ng/mL), studies with duration ≤12 weeks (WMD: 12.53 ng/mL), participants aged ≥60 years (WMD: 14.40 ng/mL), and trials with basal 25(OH)D concentrations <20 ng/mL (WMD: 11.47 ng/mL). CONCLUSIONS: This meta-analysis indicates that the supplementation of vitamin D2 significantly increases the serum concentrations of total vitamin D, 25(OH)D2, and 1,25(OH)D, but decreases 25(OH)D3 concentrations. Careful consideration of patient characteristics, dosage, and treatment duration is recommended for vitamin D2 supplementation.

Impact of Dental Midline Shift on the Perception of Facial Attractiveness in Young Adults.

Background/Objectives: The aim of this study was to quantify the threshold of a dental midline shift that would compromise facial attractiveness and indicate a need for treatment from the points of view of laypeople and dental professionals. Methods: Whole-face natural photographs of a male and a female model were digitally manipulated to create various degrees of upper and lower dental midline shifts through bodily movement of the upper or lower midlines as well as alteration of the axial inclination of the upper teeth. The samples were then assessed by two groups of observers (laypeople (LP) and dental professionals (DP)). Results: The lower midline shift did not negatively affect the DP and LP's perceptions of smile attractiveness. The first significant loss of attractiveness was registered by the DP with an upper midline shift of 1 mm in the female model. However, the LP registered this at 2 mm. The DP registered the necessity of treatment at a threshold of 2 mm in the female model and 3 mm in the male model. LP identified the need for treatment at 3 mm for both males and females. The female model was judged more critically than her male counterpart by both female and male observers. Conclusions: DP assess the midline deviation more critically than LP. Both DP and LP were more sensitive to midline deviations in the female model regardless of their own gender. Both groups registered the need for treatment at a higher threshold than the reduction in smile attractiveness.

The effects of face mask and tongue plate on maxillary deficiency in growing patients: a randomized clinical trial.

OBJECTIVE: The purpose of this randomized clinical trial was to compare the effects of facemask and tongue plate therapy in the treatment of class III malocclusion associated with maxillary deficiency in growing patients. DESIGN: Prospective, randomized clinical trial. SETTING: Department of Orthodontics, SB University of Medical Sciences Dental School, Tehran, Iran. METHODS: Fifty patients with maxillary deficiency were randomly allocated to two groups. One group was treated with a removable facemask and the other with a tongue plate. Three patients dropped out of the study leaving a final number of 47 that were analysed. The face mask group included 24 patients (12 males, 12 females) with a mean age of 9 (SD 1·2) years; while the tongue plate group included 23 patients (10 males, 13 females) with a mean age of 9·1 (SD 0·9) years. The patients lateral cephalograms obtained at the beginning and end of the study were analysed. RESULTS: Paired t-tests showed that SNA increased by 1° (SD 1·5°) in the facemask group (P<0·001) and by 2·2° (SD 1·5°) in the tongue plate group (P<0·001). With the exception of SNA and GoGn, Mann-Whitney testing showed that there were no statistically significant differences between the two groups. IMPA was found to decrease significantly in both groups. CONCLUSION: Both treatment modalities were successful in moving the maxilla forward, proclining the maxillary incisors and retroclining the mandibular incisors. The more simple design of the tongue plate might therefore confer some advantages to this system in comparison with a facemask.

A novel approach in treatment of open bite: a case report.

This case illustrates the treatment of a 12-year-old boy with an open bite, a slight Class II jaw relationship, Class I molar relationship, and a steep lower occlusal plane. The patient needed a surgical procedure due to the severity of openbite; however the surgery option was rejected. Therefore, he was treated by a Hyrax, fixed tongue appliance, posterior bite plate, reverse chin cup and fixed orthodontics. His second premolars and lower second molars were extracted during treatment. The active treatment lasted for 34 months after which favorable correction of the malocclusion was observed. The SNA angle increased by 4 degrees and the GoGn-Sn decreased by 6 degrees. This patient was treated nonsurgically and favorable profile and occlusion were obtained.

Lefort 1 osteotomy in a beta-thalassemia major patient--a case report.

Maxillary setback of patients with protruded maxilla is a complex procedure. This complexity is aggravated when combined with thalassemia. The Aim of this case report was to treat a beta-thalassemia major girl with severe maxillary protrusion. A 16 year-old beta-thalassemia major girl presented with excessive maxilla, incompetent lips and an everted upper lip was referred for treatment. She had her spleen removed at the age of 9 and her blood transfusion was stopped 3 month before referral. After leveling and aligning with 018 standard edgewise system the patient was sent for Lefort 1 osteotomy. Segmental osteotomy was denied due to excessive bleeding in the procedure. The results showed that the thalassemic patient was effectively treated with presurgical orthodontics, Lefort 1 osteotomy followed by post surgical orthodontics. Very satisfactory esthetic results were obtained in the patient after 4.5 years of active treatment.

Maxillary deficiency treatment by fixed tongue appliance--a case report.

This case illustrates orthopaedic treatment of a 12.1-year-old girl with class III malocclusion and maxillary deficiency. The patient was treated by a fixed tongue appliance in the upper jaw. First maxillary molars and premolars were banded and a hyrax was mounted on them in order to achieve lateral expansion. A fixed tongue appliance comprising of a few cribs was soldered to the anterior side of the hyrax with the purpose of pushing the maxilla in forward position. The orthopaedic stage of treatment lasted for 5 months after which favourable correction of the malocclusion was observed. The SNA angle increased by 2 degrees, the IMPA decreased by 10 degrees and mandibular plane angle (GoGn-SN) increased by 20. After this time, the fixed tongue appliance and Hyrax remained in the mouth for 3 more months as retention. This case demonstrates that fixed tongue appliance might be an alternative method to extra oral appliances in class III and maxillary deficient cases.

Are Virtually Designed 3D Printed Surgical Splints Accurate Enough for Maxillary Reposition as an Intermediate Orthognathic Surgical Guide.

Background and Aim: The accuracy of the virtually-designed 3D-printed surgical splints requires investigation for the practical use of surgical plan in the operating room. This study aimed to compare the validity of the 3D-printed and the conventional intermediate splints and evaluate the outcomes after the surgical application of the 3D-printed splint compared with the predicted values. Methods: In this study, ten patients with dentofacial deformity were recruited. Participants were analyzed by the conventional surgical planning and virtual surgical planning. The intermediate surgical splints were created by the conventional and 3D-printing methods. Maxillary movements in 3 spatial directions were measured in an articulator after the application of both splints. Correlation and agreement between the two methods were tested by intraclass correlation coefficient (ICC). After the confirmation of 3D printed splint validity for each patient, the surgery was performed using 3D printed splints. It is assumed that ideally cephalometric prediction values are going to be obtained using conventional acrylic splints (gold standard). So, as a second objective, the outcome of the surgically-applied 3D-printed splint was evaluated and compared with the predicted values and finally analyzed by the paired t-test. Results: Based on the observations, there was an excellent agreement between the virtually-designed 3D-printed and conventional intermediate surgical splints (ICC ranged between 0.83 and 0.99 for linear values). There was a good cumulative agreement of ICC greater than 0.80. Overall, the mean linear measurements were not different between conventional and 3D-printed splint on the articulator. Also, there were no significant differences between the linear and angular measurements of 2D-cephalometric prediction and postoperation values. Conclusion: The results showed cautiously the acceptable accuracy of the 3D-printed splints for several parameters in three spatial dimensions within the laboratory and clinical settings.