Calcification patterns and morphology of Sella turcica are related to anteroposterior skeletal malocclusions: A cross-sectional study

BACKGROUND

The sphenoid bone is an irregular, unpaired, symmetrical bone located in the middle of the anterior skull and is involved in craniofacial growth and development. Since the morphology of Sella turcica (ST) is associated with different craniofacial patterns, this study aimed to investigate if there is a correlation between ST morphology on the one hand and sagittal craniofacial patterns on the other hand.

METHODS

This study was conducted with a convenience sample that included Brazilian individuals undergoing orthodontic treatment. Lateral cephalograms were used to evaluate the calcification pattern and morphology of ST, as well as skeletal class by analyzing the ANB angle. Pearson's chi-square test with Bonferroni post-hoc test was performed to evaluate the association between ST calcification pattern and morphology, and anteroposterior skeletal malocclusion. The established significance level was 0.05.

RESULTS

The study collective was comprised of 305 orthodontic patients (178 (58.4 %) female, 127 (41.6 %) male), who had a mean age of 23.2 (±10.6) years. 131 participants (42.9 %) presented skeletal class I, 142 (46.6%) skeletal Class II, and 32 (10.5%) had a skeletal class III. The degree of prognathism of the mandible showed a homogenous distribution within the study collective (91 (29.9 %) orthognathic, 100 (32.9 %) retrognathic, 113 (37.2 %) prognathic mandible). Concerning the maxilla, 92 (30.2%) individuals presented an orthognathic upper jaw, whereas 60 (19.7%) showed maxillary retrognathism and 153 (50.2%) maxillary prognathism. Compared to patients with skeletal class I, skeletal class III individuals presented significantly more hypertrophic posterior clinoid process (p<0.007) and pyramidal shape of the dorsum of the ST (p<0.038).

CONCLUSIONS

Our results suggest that the hypertrophic posterior clinoid process and pyramidal shape of the ST dorsum are more prevalent in individuals with skeletal class III malocclusion.

Three-dimensional analysis of mandibular morphology asymmetry and temporomandibular joint position in patients with unilateral Brodie bite

OBJECTIVE

Previous studies have shown unilateral posterior crossbite is associated with mandibular asymmetry in morphology and position. However, it remains unclear whether unilateral Brodie bite plays a similar role in mandibular development. Therefore, this study aims to investigate the morphological and positional symmetry of mandibles in patients with unilateral Brodie bite by three-dimensional anaylsis.

METHODS

Fourteen patients with unilateral Brodie bite (mean age 18.43 ± 4.24 years) and fourteen sex- and age-matched patients with normal occlusion (mean age 18.07 ± 5.48 years) underwent cone-beam computed tomography (CBCT) scans. 3D surface mesh models of their mandibles were established using Mimics Research 19.0. The surface matching percentage was compared between the original and mirrored mandible by Geomagic Control X software. Furthermore, the dimension and position of the temporomandibular joint (TMJ) were determined for both groups using InVivoDental 5.0.

RESULTS

For surface-to-surface deviation analysis, the percentage of mismatch in patients with unilateral Brodie bite was significantly higher than the control group at ±0.50 mm, ±0.75 mm, and ±1.00 mm tolerance (P < .001). In patients with unilateral Brodie syndrome, the condyles on the scissors-bite side showed a significantly more anterior position (P = .03), greater medial inclination (P < .01), and larger posterior TMJ space (P = .01) than the non-scissors-bite side.

CONCLUSION

Patients with unilateral Brodie bite exhibit a more asymmetrical mandibular morphology, with a greater anterior condylar position and posterior joint space on the scissors-bite side, indicating that early diagnosis and treatment may be necessary for patients with unilateral Brodie bite.

The Role of Digital Surgical Planning and Surgical Guides in the Treatment of Unilateral Condylar Hyperplasia

Unilateral condylar hyperplasia (UCH) results in facial asymmetry, malocclusion, and temporomandibular joint dysfunction. Treatment consists of both surgical and orthodontic intervention. A review was performed for 4 patients with UCH who underwent digital surgical planning (DSP)-assisted condylectomy. All patients were female, aged 14 to 35 years at the time of operation with facial asymmetry and class III malocclusion. None of the patients had prior treatment and all had perioperative orthodontic appliances to provide fixation and postoperative elastic therapy. All patients underwent DSP-guided condylectomy, and intraoperative surgical cutting guides were used for 3 of the patients. All had significant improvement in facial symmetry and occlusion. None had recurrence, and additional intervention has not been required. If UCH is recognized before marked secondary changes in the maxilla, mandible, and occlusion, future orthognathic surgery may be potentially obviated. Craniomaxillofacial surgeons should consider using DSP and surgical guides in the treatment of UCH.

'Study of the maxillary yaw on cone beam computed tomography: A preliminary report and comparison between two different dento-skeletal malocclusions'

OBJECTIVES

To assess the skeletal and dental maxillary transverse compensation (yaw) on the cone beam computed tomography (CBCT) three-dimensional reconstructed image of the skull in two groups of patients, both clinically affected by a class III malocclusion with deviation of the lower midline.

MATERIALS AND METHODS

An observational retrospective study was designed to analyse differences in two groups of patients, the first one was composed by patients affected by horizontal condylar hyperplasia, the second one by patients affected by dento-skeletal asymmetric class III malocclusion. Each group was composed by 15 patients. Transverse analysis was performed by measuring five landmarks (three bilateral and two uneven) with respect to a mid-sagittal plane; sagittal analysis was performed by measuring the sagittal distance on the mid-sagittal plane between bilateral points. Means were compared through inferential analysis.

RESULTS

In the condylar hyperplasia group, all differences between the two sides were not statistically significant, nor for canines' difference (P = .0817), for molars (P = .1105) or for jugular points (.05871). In the class III group, the differences between the two sides were statistically significant for molars (P = .0019) and jugular points (P = .0031) but not for canines (P = .1158). Comparing the two groups, significant differences were found only for incisors' midline deviation (P = .0343) and canine (P = .0177).

CONCLUSION

The study of the yaw on CBCT should be integrated into three-dimensional cephalometry and could help in differentiating the various malocclusion patterns.

MicroRNA-26b regulates BMSC osteogenic differentiation of TMJ subchondral bone through β-catenin in osteoarthritis

Temporomandibular joint osteoarthritis (TMJ-OA) is a degenerative disease of the joint. The early manifestations of TMJ-OA are abnormal remodeling of condylar subchondral bone. In bone tissue, bone marrow mesenchymal stem cells (BMSCs) and osteoblasts play important roles in the differentiation and maturation of most hematopoietic cells. MicroRNA-26b (miR-26b) is upregulated during the osteogenesis of BMSCs, and miR-26b overexpression leads to the activation of β-catenin and the enhancement of osteogenesis and cartilage formation. However, the pathologic mechanism remains unclear. In the present study, we used a rat model with OA-like changes in the TMJ induced by experimental unilateral anterior crossbite (UAC) and found that the level of miR-26b was markedly lower in BMSCs from the subchondral bones of UAC rats than in those from sham control rats. MiR-26b overexpression by agomiR-26b increased condylar subchondral bone osteogenesis in UAC rats. Notably, although agomiR-26b primarily affected miR-26b levels in the subchondral bone (but not in cartilage or the synovium), the overexpression of miR-26b in BMSCs in UAC rats largely rescued OA-like cartilage degradation, while the inhibition of miR-26b in BMSCs exacerbated cartilage degradation in UAC rats. We measured the expression levels of β-catenin and related osteogenic and osteoclastic factors after using miR-26b mimics and inhibitors in vivo. Moreover, BMSCs were treated with the β-catenin blocker Wnt-C59 and then transfected with miR-26b mimics or inhibitors. Then, we examined the expression of β-catenin as the direct target of miR-26b. The results of the present study indicate that miR-26b may modulate subchondral bone loss induced by abnormal occlusion and influence the osteogenic differentiation of subchondral BMSCs through β-catenin in the context of TMJ-OA progression.

Hopeless tooth and less posterior occlusion is related to a greater risk of low handgrip strength: A population-based cross-sectional study

The effect of severely compromised teeth on masticatory function has not been properly evaluated in previous studies, as they were often considered equivalent to the healthy tooth or excluded as if absent in the dentition. Hopeless teeth, which refer to non-salvageable teeth that require extraction, can interfere with masticatory function. As posterior occlusion is directly related to the masticatory function, we evaluated pairs opposing posterior teeth (POPs) that reflect the arrangement as well as the number of remaining posterior teeth. This study investigated the relationship of a hopeless tooth to handgrip strength according to POPs in the elderly. This cross-sectional study used data from the Korea National Health and Nutrition Examination Survey (KNHANES). Among the data of 23,466 participants from 2015 to 2018, participants aged 60 years or older (n = 4,729) were included. In males with POPs scores of 0-7, considered poor posterior occlusion, the association with low handgrip strength persisted in the multivariate logistic regression model adjusted for all confounding variables. The odds ratio (OR) in the absence of hopeless teeth (OR = 1.91, 95% CI: 1.02-3.59) increased in the presence of a hopeless tooth (OR = 2.78, 95% CI: 1.42-5.47). Even with POPs scores of 8-11, considered good posterior occlusion, the association was significantly high in the presence of a hopeless tooth (OR = 2.82, 95% CI: 1.06-7.52). In females, the association disappeared in adjusted models. The fewer pairs of natural posterior teeth with occlusion, the greater the risk of low handgrip strength. Dentition containing hopeless teeth increases the risk of low handgrip strength, even in dentition with sufficient posterior occlusion. Preserving the posterior teeth in a healthy condition through personal oral hygiene and regular dental management is essential for maintaining components of physical function such as handgrip strength.

Could Vitamin D3 Deficiency Influence Malocclusion Development?

The abnormal growth of the craniofacial bone leads to skeletal and dental defects, which result in the presence of malocclusions. Not all causes of malocclusion have been explained. In the development of skeletal abnormalities, attention is paid to general deficiencies, including of vitamin D3 (VD3), which causes rickets. Its chronic deficiency may contribute to skeletal malocclusion. The aim of the study was to assess the impact of VD3 deficiency on the development of malocclusions. The examination consisted of a medical interview, oral examination, an alginate impression and radiological imaging, orthodontic assessment, and taking a venous blood sample for VD3 level testing. In about 42.1% of patients, the presence of a skeletal defect was found, and in 46.5% of patients, dentoalveolar malocclusion. The most common defect was transverse constriction of the maxilla with a narrow upper arch (30.7%). The concentration of vitamin 25 (OH) D in the study group was on average 23.6 ± 10.5 (ng/mL). VD3 deficiency was found in 86 subjects (75.4%). Our research showed that VD3 deficiency could be one of an important factor influencing maxillary development. Patients had a greater risk of a narrowed upper arch (OR = 4.94), crowding (OR = 4.94) and crossbite (OR = 6.16). Thus, there was a link between the deficiency of this hormone and the underdevelopment of the maxilla.

Condyle modeling stability, craniofacial asymmetry and ACTN3 genotypes: Contribution to TMD prevalence in a cohort of dentofacial deformities

Craniofacial asymmetry, mandibular condylar modeling and temporomandibular joint disorders are common comorbidities of skeletally disproportionate malocclusions, but etiology of occurrence together is poorly understood. We compared asymmetry, condyle modeling stability and temporomandibular health in a cohort of 128 patients having orthodontics and orthognathic surgery to correct dentofacial deformity malocclusions. We also compared ACTN3 and ENPP1 genotypes for association to clinical conditions. Pre-surgical posterior-anterior cephalometric and panometric radiographic analyses; jaw pain and function questionnaire and clinical examination of TMD; and SNP-genotype analysis from saliva samples were compared to assess interrelationships. Almost half had asymmetries in need of surgical correction, which could be subdivided into four distinct morphological patterns. Asymmetric condyle modeling between sides was significantly greater in craniofacial asymmetry, but most commonly had an unanticipated pattern. Often, longer or larger condyles occurred on the shorter mandibular ramus side. Subjects with longer ramus but dimensionally smaller condyles were more likely to have self-reported TMD symptoms (p = 0.023) and significantly greater clinical diagnosis of TMD (p = 0 .000001), with masticatory myalgia most prominent. Genotyping found two significant genotype associations for ACTN3 rs1671064 (Q523R missense) p = 0.02; rs678397 (intronic SNP) p = 0.04 and one significant allele association rs1815739 (R577X nonsense) p = 0.00. Skeletal asymmetry, unusual condyle modeling and TMD are common and interrelated components of many dentofacial deformities. Imbalanced musculoskeletal functional adaptations and genetic or epigenetic influences contribute to the etiology, and require further investigation.

Comparison of transverse maxillary dental arch width changes with self-ligating and conventional brackets in patients requiring premolar extraction - A randomised clinical trial

OBJECTIVE

The purpose of this study was to evaluate, the change in the transverse maxillary arch dimensions, in patients requiring all first premolar extractions when using Active and Passive Self-ligating brackets, and comparing them with Conventional brackets.

MATERIALS AND METHODS

This study was a non-blinded randomised clinical trial, which consisted of 42 patients (21 males and 21 females) within the age group of 16-25 years, having bimaxillary protrusion. They were divided into three groups with 14 patients each. In Group 1 - Conventional brackets (3M Unitek), in Group 2 - Passive Self-ligation brackets: Smart Clip (3M Unitek), and in Group 3 - Active Self-ligation brackets: Empower AO (American Orthodontics) were bonded. All brackets had MBT prescription and 0.02" slot size. Dental study models were taken before the start of treatment and after six months of retraction. Inter-canine and intermolar widths were measured in all the three groups in the above mentioned stages.

RESULTS

As compared to Conventional brackets, Self-ligating brackets (Passive and Active) showed greater increase in the transverse arch widths. Furthermore, between Passive and Active Self-ligating brackets, Passive Self-ligating brackets - Smart Clip (Group 2) showed a greater increment in the transverse arch dimensions, with an increase of 4.89mm in the inter-canine width and 3.4mm in intermolar width.

CONCLUSION

Significant difference was found between Self-ligating brackets and the Conventional bracket system regarding maxillary arch width dimensional changes. Passive Self-ligating brackets - Smart Clip (Group 2) showed the highest and inter-molar width increase.

Arch parameters and dental discrepancy (crowding and spacing) in a sample of an Afro-Colombian population

The aim of this study was to determine the differences in arch length, inter-canine distance, inter-premolar distance, intermolar distance and arch shape between dental discrepancies (crowding and spacing) in a sample of dental casts from the Afro-Colombian population of San Basilio de Palenque. An analytical, cross-sectional study was conducted on a convenience sample of 63 subjects aged 11 to 57years, of Afro-Colombian origin, with full dentition from first molar to first molar, without extensive caries or restorations, and excluding casts with defects due to loss. The differences between arch (upper and lower) variables were analyzed according to dental discrepancies. Plaster models digitalized with a TR1OS3 Mono scanner with exactitude (6.9 ± 0.9 pm) and precision (4.5 ± 0.9 pm) were analyzed with Orthonalyzer software. Statistical analyses were done on SPSS software (Version 20 for Windows) and Real Statistics. Spacing discrepancy of68.25% was found for upper arch and 66.66% for lower arch; crowding discrepancy of 19.04% for upper arch and 20.63% for lower arch, and an adequate ratio of 12.69% for both arches. No statistically significant difference (p>0.05) was found between arch parameters except for inter-premolar distance on the lower arch. The most frequent arch shape in the population was oval for both upper arch, with 76.19%, and lower arch, with 71.42%. Tooth size was larger in males than females but the difference was not statistically significant.

The Association between Morphological Characteristics of Palatal Rugae and Sagittal Skeletal Patterns

INTRODUCTION

To find the association between the morphological characteristics of palatal rugae and sagittal skeletal patterns.

METHODS

The retrospective charts review was conducted at the Aga Khan University Hospital from April to June 2016, and comprised data obtained from the pretreatment dental cast of orthodontic patients visiting the dental clinics over 5 years from 2011 to 2015. The sample was divided equally in three malocclusion groups based on sagittal skeletal relationship Class I, Class II and Class III. The number of palatal rugae was recorded for both right and left sides. Morphological features of the three anterior most primary rugae were recorded for the length, pattern and orientation bilaterally. SPSS 20 was used to compare the number and lengths as well as the pattern and orientation of palatal rugae among the groups.

RESULTS

Of the 165 subjects, there were 55(33.3%) in each of the three groups. Significant differences were recorded in rugae lengths among the groups at ruga 1 on both sides and rugae 2 and 3 on the left side (p<0.05 each). There were significant differences in the palatal rugae patterns among the groups (p<0.05) except at rugae 2 and 3 on the left side (p>0.05). Orientation showed significant differences at ruga 2 on the right side (p=0.02).

CONCLUSIONS

No specific pattern was associated with any skeletal pattern. Further studies are required to evaluate three-dimensional characteristics of rugae to assess the association between palatal rugae and sagittal skeletal patterns.

Association Between Variations In Sella Turcica Dimensions And Morphology And Skeletal Malocclusions

BACKGROUND

The growth of sella turcica is completed early in life, therefore it can be used as a stable landmark for the prediction of future skeletal malocclusions. This early diagnosis may help in planning less complicated treatment modalities. Therefore, this study aimed to evaluate the relationship between sella turcica dimensions and morphology with various skeletal patterns.

METHODS

A cross sectional study was conducted using the pre-treatment cephalograms of 180 subjects aged 13-19 years. The subjects were divided into two groups based on skeletal patterns. The dimensions of sella turcica and skeletal patterns were digitally measured using View Pro-X software. One-way ANOVA was applied to compare sella turcica dimensions among skeletal patterns. Sella dimensions and vertical growth patterns were compared using Post-hoc Tukey test. Chi-square test was applied to compare sella morphology among malocclusion groups. Results were taken as statistically significant at p-value of ≤0.05.

RESULTS

Sella dimensions showed insignificant differences among sagittal groups whereas, significant differences were found for sella length (p≤0.02) and depth (p≤0.03) among the vertical groups. Multiple comparisons showed significant differences between sella length (p≤0.03) and diameter (p≤0.04) between normodivergent versus hyperdivergent groups. Moreover, significant differences were found in the sella turcica morphology among sagittal malocclusion (p≤0.03).

CONCLUSIONS

Increased dimensions of sella turcica were associated with hyperdivergent growth pattern. Bridging of the sella turcica was found to be prevalent in class III malocclusion.

Systematic Review and Meta-Analysis of Passive Lower Lingual Arch for Resolving Mandibular Incisor Crowding and Effects on Arch Dimension

Purpose: This systematic review and meta-analysis assessed whether passive lower lingual arch (LLA) resolves mandibular incisor crowding and affects mandibular arch dimension. Methods: We searched PubMed, Web of Science, and Cochrane Database of Systemic Reviews for both randomized controlled trials and nonrandomized studies from 1940 to March 2018. Inclusion criteria were healthy children in mixed dentition with mandibular incisor crowding treated with LLA. Our primary outcome was the amount of mandibular incisor crowding resolved after LLA, and secondary outcomes were effects of LLA mandibular arch dimension changes versus untreated controls (UTCs). Results: From 559 screened articles, seven qualified for systematic review and meta-analyses. The average resolution of mandibular incisor crowding after LLA was 5.10 mm (P=.001) with the evidence assessed as very low quality. Arch perimeter and arch length changes were not significantly different between LLA and UTCs (P=0.20 and P=0.87, respectively). There were significant small increases of 0.79 mm in intercanine width (P<.001) and 0.69 mm in intermolar width (P=.003) with a low and a very low quality of evidence, respectively. Conclusions: Lower lingual arch was effective in resolving mandibular incisor crowding without any significant arch perimeter or arch length changes of greater than one mm.

A Study on the Evaluation of Pharyngeal Size in Different Skeletal Patterns: A Radiographic Study

AIM

The aim of this study was to evaluate the upper and lower pharyngeal airway dimensions were affected by different skeletal malocclusions.

MATERIALS AND METHODS

Lateral cephalograms of 120 subjects were used to measure the pharyngeal airway and were divided into three groups (each group included 40 subjects) according to ANB angle: Class I (ANB angle 2° ≤ ANB ≤ 4°), Class II (ANB angle(ANB ≥ 6°), and Class III (ANB angle ≤ 0°). Various linear cephalometric airway measurements (14 measurements) were used to evaluate pharyngeal airway at various levels. Statistical analyses were performed Using the ANOVA and student t-test.

RESULTS

PNS-ppwl (p < 0.001) and McNamara' lower pharynx dimension (p < 0.05) showed a statistically significant difference between the groups. Two out of 14 variables ie Ba-PNS and t-ppw showed a statistically significant difference between male and female. In both measurements, the difference is significant only in the Class II group with the level of significance being (p < 0.001) in Ba-PNS measurement, and (p < 0.05) in t-ppw measurement. In both measurements males have statistically significant higher mean values than the females.

CONCLUSION

The dimensions of pharyngeal structures were not affected by the changes of the ANB angle. The sagittal skeletal pattern does not seem to influence the variations in the upper airway dimension. There was no significant difference in the dimensions of pharyngeal structures among males and females.

CLINICAL SIGNIFICANCE

The upper and lower pharyngeal airway dimensions are affected by different skeletal malocclusions can significantly aid in Orthodontic treatment planning.

Agenesis of Permanent Canines in Orthodontic Patients: Prevalence, Location, Treatment Options and Outcomes

Purpose: Tooth agenesis is one of the most common anomalies of the human dentition, found most often in the maxillary anterior region and in the mandibular and maxillary premolar regions. Little information is available on the prevalence and distribution of permanent canine agenesis. The purpose of this retrospective study was to evaluate the prevalence and distribution of permanent canine agenesis in orthodontic patients and describe treatment options and outcomes. Methods: The records of 3,000 consecutively treated patients in the Department of Orthodontics, Tel Aviv University, Tel Aviv, Israel were reviewed. The pre-treatment facial and intraoral clinical photographs as well as panoramic and periapical radiographs were used to detect permanent canine agenesis in both dental arches. The data were recorded according to sex, age, number of missing canines, and their location. Results: Twenty-three patients (0.76 percent), nine males (39 percent) and 14 females (61 percent) had 38 congenitally missing canines. Of these, 22 (58 percent) were missing in the maxilla and 16 (42 percent) were missing in the mandible. Conclusions: The overall prevalence of missing permanent canines in our population was 0.76 percent. The female-to-male prevalence ratio was approximately three to two and more canines were missing in the maxilla than in the mandible.

Positional and dimensional temporomandibular joint changes after correction of posterior crossbite in growing patients: A systematic review

OBJECTIVE

To elucidate the positional and dimensional temporomandibular joint (TMJ) changes after correction of posterior crossbite in growing patients.

MATERIALS AND METHODS

A systematic unrestricted search was done in six databases until June 27, 2017. A manual search in the reference lists of the included studies and gray literature was also performed. The eligibility criteria included randomized controlled trials and prospective nonrandomized controlled clinical trials and a sample of growing subjects with posterior crossbite that required maxillary expansion. Risk of bias assessment was performed using Cochrane's Risk of Bias Tool. The literature search, study inclusion, risk of bias assessment, evaluation of quality of evidence (GRADE), and data extraction were performed by two reviewers independently.

RESULTS

Only two articles were finally eligible to be included in the qualitative analysis. Both studies were RCTs and were assessed as having unclear risk of bias. Meta-analysis was not possible since one study used cone-beam computed tomography as an assessment tool while the other used ultrasonography. One study reported significant reduction in the condylar positional difference between centric and habitual occlusion in the treatment group, while no spontaneous correction of condylar asymmetric position occurred in the control group. The other study reported minor changes of condylar position in both treatment and control groups.

CONCLUSIONS

The current available data provide insufficient and weak evidence to form a solid and firm conclusion. There is poor, very low-quality evidence regarding the positional and dimensional effects of posterior crossbite correction on the TMJs.

A new method for the treatment of unilateral posterior cross-bite: a three-dimensional finite element stress analysis study

BACKGROUND

Stress relieving corticoto mies during the treatment of maxillary expansion are needed in adult patients.

METHODS

Three-dimensional (3D) finite element model was prepared, and finite element analysis was processed to evaluate the stress distributions within the skull and maxillary teeth during surgically assisted rapid maxillary expansion (SARME) treatment.

RESULTS

Expansion forces generated more stress on the corticotomy-applied part of the maxilla. The stress levels decreased dramatically above the corticotomy line.

CONCLUSION

Asymmetric transveral maxillary expansion might be achieved from a symmetric force generating screw during SARME treatment. SARME osteotomies may concentrate the stress in the expanding maxilla and reduce the pain in other parts of the cranium.

Dental arch dimensions, form and tooth size ratio among a Saudi sample

Objectives:

To determine the dental arch dimensions and arch forms in a sample of Saudi orthodontic patients, to investigate the prevalence of Bolton anterior and overall tooth size discrepancies, and to compare the effect of gender on the measured parameters.

Methods:

This study is a biometric analysis of dental casts of 149 young adults recruited from different orthodontic centers in Jeddah, Saudi Arabia. The dental arch dimensions were measured. The measured parameters were arch length, arch width, Bolton’s ratio, and arch form. The data were analyzed using IBM SPSS software version 22.0 (IBM Corporation, New York, USA); this cross-sectional study was conducted between April 2015 and May 2016.

Results:

Dental arch measurements, including inter-canine and inter-molar distance, were found to be significantly greater in males than females (p<0.05). The most prevalent dental arch forms were narrow tapered (50.3%) and narrow ovoid (34.2%), respectively. The prevalence of tooth size discrepancy in all cases was 43.6% for anterior ratio and 24.8% for overall ratio. The mean Bolton’s anterior ratio in all malocclusion classes was 79.81%, whereas the mean Bolton’s overall ratio was 92.21%. There was no significant difference between males and females regarding Bolton’s ratio.

Conclusion:

The most prevalent arch form was narrow tapered, followed by narrow ovoid. Males generally had larger dental arch measurements than females, and the prevalence of tooth size discrepancy was more in Bolton’s anterior teeth ratio than in overall ratio.

Comparison of Beta and ANB Angles for Evaluation of Sagittal Skeletal Discrepancy: A Cephalometric Study

AIM

Diagnosis in orthodontic cases and treatment planning is a precise assessment of sagittal jaw relationship. A number of angular and linear measurements have been used to attain correct diagnosis. The present study is done to compare beta angle and A point-nasion-B point (ANB) angle for sagittal skeletal discrepancies.

MATERIALS AND METHODS

A total of 105 subjects were included in between the age group of 18 and 24 years and were categorized based on the skeletal patterns as class I, class II, and class III having a sample of 35 in each group. Based on the ANB angle and patients' profile, the sample was divided into different skeletal groups. Beta angle is the angle amid the perpendicular from C to B line through point A and the A-B line. Analysis of variance (ANOVA) and post hoc Scheffe's test were applied to analyze dependent variables. The level of significance was set at p-value 0.05.

RESULTS

The mean scores of ANB for class I skeletal pattern were 2.46 ± 0.460, for class II, 5.64 ± 1.258, and for class III, -1.03 ± 1.618. Similarly, significant differences were observed in beta angle for class I skeletal pattern as 31.71 ± 3.885, for class II, 24.97 ± 2.162, and for class III, 39.26 ± 3.649.

CONCLUSION

Both ANB and beta angle showed significant differences with different skeletal patterns.

CLINICAL SIGNIFICANCE

Both ANB and beta angle are awfully supportive diagnostic measurements to scrutinize sagittal jaw relationship.

Comparative Assessment of Facial Asymmetry in Malocclusion using Posteroanterior View

AIM

The study was conducted to assess facial asymmetry in various dental malocclusions and to determine asymmetry in lower, mid, and upper face and jaws using posteroanterior cephalometric analysis.

MATERIALS AND METHODS

Overall, 120 posteroanterior cepha-lograms were taken of individuals between 12 and 25 years of both sexes, and were divided into four groups: Angle's class I excellent occlusion, Angle's class I malocclusion, Angle's class II malocclusion, and Angle's class III malocclusion. These cepha-lograms were traced and Grummon's analysis was performed.

RESULTS

In Angle's class I occlusion and Angle's class II malocclusion, the results obtained showed asymmetry present in the upper face. Correlation was found between occlusion, maloc-clusion, and facial asymmetry.

CONCLUSION

Facial asymmetry was found in all dental occlusions whether excellent or malocclusion group, with maximum asymmetry having upward trend toward upper face starting from lower.

CLINICAL SIGNIFICANCE

For the success of the orthodontic treatments in various types of malocclusion and to determine the facial asymmetry, posteroanterior view can be very helpful, as it gives additional information which can be utilized to augment treatment planning and improve prognosis in terms of relapse prevention.

TACTICS OF THE TREATMENT OF TEETH TRANSPOSITION (CASE REPORTS)

Transposition of teeth - mutual exchange of the teeth position in the dental arch, it's a rare anomaly of the dentoalveolar apparatus. Most often in the transposition process the upper canines are involved in combination with the first premolars. Anomaly is mainly caused by an incorrect location of the teeth germs. Full correction is optimal in the treatment of transposition in terms of function and aesthetics, but in most cases, the movement of these teeth in their physiological position is impossible. Aim - to define and argue the tactics of the orthodontist in the treatment of patients with teeth transposition. The algorithm for curation of patients with teeth transposition consisted of several blocks: the establishment of etiologic factors, clinical and additional examination methods, planning and making treatment tactics, the stages of active treatment and management of the patient in the retention period. Among additional methods of examination were used: orthopantomography, 3D computer tomography, photometry, anthropometry. For a visual demonstration of orthodontic treatment, an curation algorithm of two patients with a teeth transposition was described. The choice of treatment options depended on the location and type of transposition (full or partial), the age of the patient, the condition of the periodontal tissue, the size of the teeth and their roots, the degree of tooth dislocation and root inclination, the type of occlusion, the bone thickness in the region of alveolar process, the level of cooperation between the patient and the doctor. Knowledge of the treatment tactics of patients with teeth transposition allows the orthodontist to normalize the individual teeth position, restore function and aesthetics in an optimal time. After our patient's treatment, positive esthetic, morphological and functional results were achieved.

Influence of tooth position on wind instrumentalists' performance and embouchure comfort : A systematic review

PURPOSE

To systematically search the scientific literature concerning the influence of tooth position on wind instrumentalists' performance and embouchure comfort.

METHODS

The PubMed, Cochrane, and Embase databases were searched up to November 2017. The main orthodontic journals were searched for papers older than the inception date of PubMed. Grey literature was sought via Google Scholar. Eligible studies were critically appraised and analysed.

RESULTS

The searches retrieved 54 papers. Only two met the inclusion criteria. Searching the orthodontic journals and Google Scholar resulted in two additional eligible studies. All four studies had a cross-sectional design. The sample sizes ranged from 20-100 participants, varying from children to professional musicians. Because of a large heterogeneity in outcome variables, no meta-analysis could be performed. Descriptive analysis shows that there are indications that tooth irregularities have a negative influence on embouchure comfort and performance of a wind instrument player. A large overjet may impede the embouchure of brass musicians and may have a negative influence on trumpet player performance. A wide jaw form seems more beneficial to trumpet player performance than a small jaw form. Furthermore, players of all types of wind instruments can experience embouchure difficulties from extreme spacing or an open bite.

CONCLUSION

Tooth position can influence musical performance and embouchure comfort of wind instrumentalists. A Class I relationship without malocclusion seems appropriate for every type of wind instrument. The more extreme the malocclusion, the greater the interference with wind instrumentalists' performance and embouchure comfort. Evidence however is limited.

Collaborative treatment for a case of condylar hyperplastic facial asymmetry

Facial asymmetry can be caused by unilateral condylar hyperplasia. In such cases, it may be difficult to achieve symmetry since there is dentoalveolar compensation on the affected side, and the occlusal cant does not correspond to the frontal mandibular deviation. In the case presented, surgical orthodontic treatment and orthognathic surgery planning was accomplished for a patient with facial asymmetry due to condylar hyperplasia. The surgical plan was devised with particular attention to the severe dentoalveolar compensation. In this case, prior to the two-jaw surgery, the occlusal cant and frontal mandibular plane inclination was corrected through impaction of the left molar region by segmental osteotomy. Facial asymmetry and severe dentoalveolar compensation were successfully corrected after a unilateral segmental osteotomy and two-jaw surgery, resulting in a stable occlusal relationship and facial symmetry as well as good jaw function. Collaboration between the orthodontists and maxillofacial surgeons was essential for the successful treatment of the patient.

Dimensional changes in the palate associated with slow maxillary expansion for early treatment of posterior crossbite

OBJECTIVES

To compare palatal symmetry, dimensions, and molar angulations following early mixed-dentition slow maxillary expansion with parameters in normal controls.

MATERIALS AND METHODS

A total of 30 patients treated with a Haas-type expander for unilateral posterior crossbite with functional shift were compared with 30 controls matched for dental age, gender, and molar relationship. Records were taken before (T1) and after expansion (T2). Palatal width, surface area, volume, and molar angulations were measured on digitized models. Surface area and volume were split in half then divided into anterior, middle, and posterior segments to measure symmetry. Student's t-test was used to assess group differences.

RESULTS

Mean intercanine width increased 4.65 mm, and intermolar width increased 4.76 mm. The treated mean surface area increased 127.05 mm² compared with 10.35 mm² in controls. The treated palatal volume increased 927.55 mm³ compared with 159.89 mm³ for controls. At T1, the controls showed significant differences in surface area and volume between the anterior palatal segments. At T2, this difference occurred in surface area of middle palatal segments of the treated sample. First permanent molars showed an increased buccal and distal inclination after treatment, opposite to controls. The increase in buccal inclination was greater on the crossbite side.

CONCLUSIONS

The Haas-type expander results in similar expansion across the canines and first molars. A palate that is symmetrical before expansion may become asymmetric after expansion but only in the middle segment. Changes in individual molar angulation following palatal expansion can be measured without radiation imaging.

Analysis of Dental Arch Relationships in Swedish Unilateral Cleft Lip and Palate Subjects: 20-Year Longitudinal Consecutive Series Treated with Delayed Hard Palate Closure

Objective:

To evaluate the dental arch relationships for a consecutive series from Goteborg, Sweden, who had delayed hard palate closure.

Design:

Retrospective study.

Setting:

Sahlgrenska University Hospital, Goteborg, Sweden.

Patients:

The dental study models of 104 consecutive unilateral cleft lip and palate subjects. The study cohort was born between 1979 and 1994. Longitudinal records were available at ages 5 (n = 94), 10 (n = 97), 16 (n = 59), and 19 years (n = 46). Five assessors rated models according to the GOSLON Yardstick on two separate occasions each.

Interventions:

These patients had been operated upon according to the Goteborg protocol of delayed hard palate closure (at age 8 years).

Results:

85% of subjects were rated in groups 1 and 2 (excellent or very good outcome), 12% were rated in group 3 (satisfactory), and 3% were assigned to group 4 (poor). No patients presented in Group 5 (very poor). Weighted kappa statistics for double determination of Yardstick allocation for five assessors demonstrated values between .65 and .90 for interrater agreement (good/very good) and between .70 and .90 for intrarater agreement (very good).

Conclusions:

Delayed hard palate closure as practiced in Goteborg since 1979 has produced the best GOSLON Yardstick ratings in a consecutive series of patients ever recorded worldwide, since the Yardstick was first used in 1983. However, it is noteworthy that a new protocol has been introduced in Goteborg since 1994, in which hard palate closure is done at 3 years due to concerns regarding speech.

Retrospective Evaluation of Treatment Outcome in Japanese Children with Complete Unilateral Cleft Lip and Palate. Part 1: Five-Year-Olds’ Index for Dental Arch Relationships

Objective:

To evaluate the dental arch relationships of Japanese children with complete unilateral cleft lip and palate (UCLP) and to examine the 5-year-olds’ index for its validity.

Design:

Retrospective study and comparison with previous reports.

Subjects:

One hundred thirty-six children with complete UCLP who received primary cheiloplasty and palatoplasty in the Kyushu University Hospital from 1966 to 1999.

Materials:

Dental models taken from children 53 to 67 months of age and their cephalograms.

Methods:

Study models were assessed using five scores; 1 = excellent, 2 = good, 3 = fair, 4 = poor, and 5 = very poor, in accordance with the 5-year-olds’ index and also evaluated using Huddart and Bodenham's numerical classification. Dental arch widths, three-dimensional maxillary dental arch form, and lateral cephalograms were traced and measured. The outcome by 5-year-olds’ index was compared with Huddart and Bodenham's numerical classification, dental arch dimensions, and cephalometric measurements.

Results:

Occlusal outcome evaluated by the 5-year-olds’ index was rated 2.95, which was classified as fair. This index rating showed a significant relationship with numerical classification and dental arch length, but not with dental arch width. The index showed a relationship with mandibular form and position, but not with maxillary position.

Conclusion:

The occlusal outcome of the cases with UCLP was fair as evaluated using the 5-year-olds’ index. The index evaluates the anteroposterior relationship of maxillary/mandibular dental arches but does not evaluate the collapse of maxillary segments.

Dental anomalies in different growth and skeletal malocclusion patterns

OBJECTIVES

To evaluate prevalence, distribution, and sexual dimorphism of dental anomalies (DA) among different skeletal malocclusions (SM) and growth patterns (GP) under the hypothesis that specific clinical patterns exist and may indicate common etiological roots.

MATERIALS AND METHODS

A total of 1047 orthodontic records of patients older than 8 years were evaluated. The SN-GoGn angle was used to classify GP (hypodivergent, normal, and hyperdivergent), and the ANB angle was used to verify SM (Angle Classes I, II, and III). These assessments were done from lateral cephalometric radiographs. DA were diagnosed using panoramic radiographs by one calibrated investigator. Odds ratios, chi-square, and Student's t-tests were used.

RESULTS

Of the subjects, 56.7% were female, with mean age of 16.41 (±10.61) years. The prevalence of DA was 15.7%. Impaction and tooth agenesis were the most prevalent DA, with relative frequencies of 14.4% and 9.7%, respectively. DA were most prevalent in Class III SM (80.8%) and in hypodivergent GP (82.5%), although this was not statistically significant. Tooth agenesis ( P < .01) and microdontia ( P = .025) were significantly more common among hypodivergent GP and Class III SM, respectively.

CONCLUSIONS

The results of this study support the idea that DA are preferentially associated with certain patterns of malocclusion.

Reliability of three-dimensional anterior cranial base superimposition methods for assessment of overall hard tissue changes: A systematic review

OBJECTIVE

The purpose of this systematic review was to synthesize the available literature concerning the reliability of three-dimensional superimposition methods when assessing changes in craniofacial hard tissues.

MATERIALS AND METHODS

Four electronic databases were searched. Two authors independently reviewed potentially relevant articles for eligibility. Clinical trials, cohort, case-control, and cross-sectional studies that evaluated the reliability of three-dimensional superimposition methods on the anterior cranial base were included.

RESULTS

Six studies fulfilled the inclusion criteria. Four studies used the voxel-based registration method, one used the landmark-based method and one used the surface-based method. Regarding reliability, the voxel-based studies showed on average a difference of 0.5 mm or less between images. The optimized analysis using a six-point correction algorithm in the landmark-based method showed 1.24 mm magnitude of error between images.

CONCLUSIONS

Although reliability appears to be adequate, the small sample size and high risk of bias among studies make available evidence still insufficient to draw strong conclusions.

Relationship between voice function and skeletal effects of rapid maxillary expansion

OBJECTIVE

To evaluate the effects of rapid maxillary expansion (RME) on the vocal quality, maxillary central incisors, midpalatal suture, and nasal cavity in patients with maxillary crossbite.

MATERIALS AND METHODS

Coronal CT scans of 30 subjects (14 boys, 16 girls; mean age, 12.01 ± 0.75) were taken before RME (T0), and at the end of the expansion phase (T1). Voice samples of all patients were recorded with a high-quality condenser microphone (RODE NT2-A) on a desktop computer at T0 and T1. Statistical analyses were performed using a paired-sample t-test. The degree of association between the changes in the voice parameters and nasal width was assessed with Pearson's correlation.

RESULTS

RME treatment produced a significant increase in the transverse dimensions of the midpalatal suture and nasal cavity between T0 and T1 ( P < .05). The maximum F0 and jitter (%) results were shown to decrease statistically significantly from T0 to T1 ( P < .001 and P = .042, respectively). Between T0 and T1, shimmer (%) and shimmer (dB) exhibited statistically significant increases ( P = .037 and P = .019, respectively).

CONCLUSIONS

After RME therapy, voice quality differences were found to be associated with increases in nasal width.

Bayesian Networks Analysis of Malocclusion Data

In this paper we use Bayesian networks to determine and visualise the interactions among various Class III malocclusion maxillofacial features during growth and treatment. We start from a sample of 143 patients characterised through a series of a maximum of 21 different craniofacial features. We estimate a network model from these data and we test its consistency by verifying some commonly accepted hypotheses on the evolution of these disharmonies by means of Bayesian statistics. We show that untreated subjects develop different Class III craniofacial growth patterns as compared to patients submitted to orthodontic treatment with rapid maxillary expansion and facemask therapy. Among treated patients the CoA segment (the maxillary length) and the ANB angle (the antero-posterior relation of the maxilla to the mandible) seem to be the skeletal subspaces that receive the main effect of the treatment.

Characteristic of Malocclusion among Saudi Special Need Group Children

INTRODUCTION

The present study analyzed the characteristics of malocclusions, occlusal traits among Special Health care Needs (SHCN) children with Down syndrome (DS) and autism disorder (AD) in Riyadh City, Kingdom of Saudi Arabia.

MATERIALS AND METHODS

A total of 100 DS and 100 AD children from five rehabilitation centers in and around Riyadh, Kingdom of Saudi Arabia, were included in the study. Any children with history of ongoing medical treatment, extraction, or orthodontic treatment were excluded from the study. Out of the 200 patients examined, 131 were males and 69 were females and the age of the children ranged from 6 to 14 years. The children were examined for malocclusion characteristics using the Angle's classification of malocclusion, and also other occlusal traits, such as overjet, overbite, cross bite, and open bite were also determined. The data obtained were analyzed using Statistical Package for the Social Sciences, version 16 to generate descriptive statistics for each variable.

RESULTS

The analyzed data of the right and left permanent molar relation showed higher incidence of class III malocclusion (66%) in DS children as compared with (3-4%) AD children. The AD children presented with higher percentage of class I malocclu-sion (40-41%) as compared with (10-14%) DS children. During examination of the primary molars, the analyzed data showed that left primary molar had more mesial shift in AD children as compared with DS children.

CONCLUSION

Down syndrome children had high incidence of class III malocclusion and autistic children had high incidence of class I malocclusion. Overall, the DS children were more prone to malocclusion.

CLINICAL SIGNIFICANCE

This study provides database for health professionals in Saudi Arabia in regard to malocclusion of autis-tics and DS patients.

Comparison of the force levels among labial and lingual self-ligating and conventional brackets in simulated misaligned teeth

Background/objective

The aim of this study was to evaluate force levels exerted by levelling arch wires with labial and lingual conventional and self-ligating brackets.

Materials/methods

The tested orthodontic brackets were of the 0.022-in slot size for labial and 0.018-in for lingual brackets and were as follows: 1. Labial brackets: (i) conventional bracket (GAC-Twin, Dentsply), (ii) passive self-ligating (SL) brackets (Damon-Q®, ORMCO; Ortho classic H4™, Orthoclassic; FLI®SL, Rocky Mountain Orthodontics) and (iii) active SL brackets (GAC In-Ovation®C, DENTSPLY and SPEED™, Strite). 2. Lingual brackets: (i) conventional brackets (Incognito, 3M and Joy™, Adenta); (ii) passive SL bracket (GAC In-Ovation®LM™, Dentsply and (iii) active SL bracket (Evolution SLT, Adenta). Thermalloy-NiTi 0.013-in and 0.014-in arch wires (Rocky Mountain Orthodontics) were used with all brackets. The simulated malocclusion represented a maxillary central incisor displaced 2 mm gingivally (x-axis) and 2 mm labially (z-axis).

Results

Lingual bracket systems showed higher force levels (2.4 ± 0.2 to 3.8 ± 0.2 N) compared to labial bracket systems (from 1.1 ± 0.1 to 2.2 ± 0.4 N). However, the differences between SL and conventional bracket systems were minor and not consistent (labial brackets: 1.2 ± 0.1 N for the GAC Twin and 1.1 ± 0.1 to 1.6 ± 0.1 N for the SL brackets with 0.013-in thermalloy; lingual brackets: 2.5 ± 0.2 to 3.5 ± 0.1 N for the conventional and 2.7 ± 0.3 to 3.4 ± 0.1 N for the SL brackets with 0.013-in Thermalloy).

Limitations

This is an in vitro study with different slot sizes in the labial and lingual bracket systems, results should be interpreted with caution.

Conclusions/implications

Lingual bracket systems showed higher forces compared to labial bracket systems that might be of clinical concern. We recommend highly flexible nickel titanium arch wires lower than 0.013-in for the initial levelling and alignment especially with lingual appliances.

Evaluation of palatal rugae pattern in different sagittal skeletal relationship adolescent subjects

The purpose of this study was to evaluate the morphological structure of palatal rugae in Turkish orthodontic subjects with different sagittal skeletal malocclusions. Orthodontic dental casts of 105 patients (Class I [23 females, 12 males]; 35, Class II [18 females, 17 males]; and 35, Class III [14 females, 21 males] 10-22 years old) were analyzed for rugae patterns. Palatal rugae pattern and number, direction of rugae alignment, shape of incisive papilla were analyzed. Modified Thomas and Kotze classification was performed to analyze palatal rugae characteristics. The data were analyzed using the Kruskal-Wallis test. Wavy and curved types were the most common types of rugae pattern in all groups (Class I, Class II, Class III). As regards to the number of primary and secondary rugae on the left and right sides, there was no statistically significant difference among subjects with different skeletal malocclusions. Droplet-shaped incisive papilla was the most common form of incisive papillae among different skeletal malocclusion groups. The most common palatal rugae were direction type arranged in the horizontal direction. All rugae patterns were unique for each individual. The use of antemortem or postmortem palatal rugae records may facilitate identification of the suspects in forensic investigations by enabling facial reconstruction through skeletal malocclusions.

Comparison of reconstructed rapid prototyping models produced by 3-dimensional printing and conventional stone models with different degrees of crowding

INTRODUCTION

Rapid prototyping models can be reconstructed from stereolithographic digital study model data to produce hard-copy casts. In this study, we aimed to compare agreement and accuracy of measurements made with rapid prototyping and stone models for different degrees of crowding.

METHODS

The Z Printer 450 (3D Systems, Rock Hill, SC) reprinted 10 sets of models for each category of crowding (mild, moderate, and severe) scanned using a structured-light scanner (Maestro 3D, AGE Solutions, Pisa, Italy). Stone and RP models were measured using digital calipers for tooth sizes in the mesiodistal, buccolingual, and crown height planes and for arch dimension measurements. Bland-Altman and paired t test analyses were used to assess agreement and accuracy. Clinical significance was set at ±0.50 mm.

RESULTS

Bland-Altman analysis showed the mean bias of measurements between the models to be within ±0.15 mm (SD, ±0.40 mm), but the 95% limits of agreement exceeded the cutoff point of ±0.50 mm (lower range, -0.81 to -0.41 mm; upper range, 0.34 to 0.76 mm). Paired t tests showed statistically significant differences for all planes in all categories of crowding except for crown height in the moderate crowding group and arch dimensions in the mild and moderate crowding groups.

CONCLUSIONS

The rapid prototyping models were not clinically comparable with conventional stone models regardless of the degree of crowding.

Oral health considerations in a patient with oligosymptomatic ectrodactyly-ectodermal dysplasia-cleft syndrome

Ectrodactyly-ectodermal dysplasia-cleft (EEC) syndrome-a complex, pleiotropic disorder resulting in multiple congenital anomalies-has an unpredictable clinical expression and is typically manifested as an autosomal-dominant trait. This article presents a rare case of oligosymptomatic EEC syndrome in a 19-year-old man who exhibited atypical dental findings but no cleft lip or palate. This article is intended to create awareness about this rare syndrome and highlight the role of oral healthcare specialists in improving the quality of life for patients with EEC.

Objectively measured compliance during early orthodontic treatment: Do treatment needs have an impact?

BACKGROUND

Objective assessment of daily wear time of removable appliances is possible, so the next step is to ascertain whether the severity of malocclusion influences patients' compliance. This could help resolve the controversy over the question of whether removable appliance therapy truly works.

OBJECTIVES

The aim of the study was to investigate whether the patient's orthodontic treatment needs affect the cooperation between the patient and the doctor, and to find a correlation that could affect recommendations for orthodontic treatment.

MATERIAL AND METHODS

The study involved 58 patients (29 boys, 29 girls) aged 9-12 years, who qualified for treatment with removable appliances equipped with a sensor system. The patients were divided into four groups according to their Index of Orthodontic Treatment Need dental health component scores. Over a 9-month period, data stored in the sensors were compared with the recommended daily wear time (DWT) of the appliances, and a statistical analysis was conducted.

RESULTS

DWT differed considerably in all the groups. Statistically significant differences in the mean DWT values occurred only when extreme values of the IOTN DHC were compared.

CONCLUSIONS

The degree of patient compliance depends to a small extent on the severity of malocclusion. Patients with mild malocclusion will probably be less likely to cooperate. Among patients with severe malocclusion, compliance may be unpredictable. Patient compliance is an important background factor that can explain a lot of the controversy over the effectiveness of treatment with removable appliances.

Internal derangement in the temporomandibular joint of juveniles with clinical signs of TMD : MRI-assessed association with skeletal and dental classes

AIM

The aim of this study was to investigate possible correlation of specific skeletal or dental class in children and adolescents with clinical signs of temporomandibular dysfunction (TMD) with the severity of internal derangement (ID) of the temporomandibular joint.

MATERIALS AND METHODS

Based on MRI images, the ID of 232 juvenile temporomandibular joints in 116 patients were retrospectively recorded. The distribution of the ID stages within the skeletal and dental classes was compared by means of the χ ² test.

RESULTS

Excluding the comparison between skeletal Class I (S I) and skeletal Class II (S II; p < 0.05), no statistically significant differences in the distribution of the ID stages were found between the skeletal classes (p > 0.05). No statistically significant differences were found when comparing the distribution of the ID stages between the dental classes (p > 0.05).

CONCLUSION

According to these findings, there is no skeletal or dental class that is related to higher degrees of internal derangement in the TMJs of children and adolescents presenting clinical signs of TMD. Therefore, it is not possible to draw conclusions about the severity of the ID in relation to the dental and skeletal class in symptomatic juvenile TMJs.

Exploration of variations in positions of upper and Lower incisors, overjet, overbite, and irregularity Index in orthodontic patients with dissimilar depths of Curve of spee

BACKGROUND

The position and arrangement of teeth as well as the entire scheme of occlusion differs from one individual to the other .The purpose of this study was to examine differences in position and inclination of incisors, overjet, overbite and lower arch crowding in subjects with different depths of curve of Spee and to determine correlations between depth of curve of Spee and these variables.

METHODS

The sample comprised of 114 patients (55 females and 59 males) with fully erupted permanent second molars (age 12-25 years), having no history of previous orthodontic treatment, no craniofacial anomalies, and no missing permanent teeth. Study parameters were assessed by using pretreatment lateral cephalograms and dental casts of orthodontic patients. The entire sample was divided into three groups according to depth of curve of Spee (mild Spee=38, moderate Spee=38, severe Spee=38). Descriptive statistics were calculated. Differences between the Spee groups were assessed by analysis of variance. In addition, correlation coefficients were calculated between curve of Spee and other parameters.

RESULTS

Statistically significant differences were found in upper incisor inclination (p=0.000), lower incisor inclination (p=0.003), Steiner's mandibular plane angle (p=0.000), overjet (p=0.001), overbite (p=0.000) and irregularity index (p=0.008) among the Spee groups. Moreover, statistically significant positive correlations were found between curve of Spee and overjet, overbite and irregularity index. Upper and lower incisor inclinations as well as mandibular plane angle were found to have statistically significant but negative correlations with curve of Spee.

CONCLUSIONS

Overjet and overbite in severe Spee group are larger than in mild and moderate Spee groups. There is negative correlation between curve of Spee depth and inclinations of upper and lower incisors. There is positive correlation between curve of Spee depth and severity of lower anterior crowding and Steiner's mandibular plane angle.

Relationship between Orthodontic Treatment Plan and Goslon Yardstick Assessment in Japanese Patients with Unilateral Cleft Lip and Palate: One-stage vs. Two-stage Palatoplasty

The present study targeted patients with unilateral cleft lip and palate (UCLP) undergoing either one - (Wardill technique) or two-stage palatoplasty (Perko technique). Correlations between Goslon Yardstick scores and orthodontic appliances used and whether an osteotomy was performed were investigated. No differences were observed between the two types of palatoplasty in terms of Goslon Yardstick scores. A palatal expander and protraction facemask were used in Phase I of orthodontic treatment. The palatal expander was selected for most patients with UCLP in Phase I, regardless of the surgical technique used. A protraction facemask was used in patients undergoing the Wardill procedure who had a Goslon Yardstick score placing them in Group 3 or 4. In contrast, a protraction facemask was used in patients undergoing the Perko procedure who had a Goslon Yardstick score placing them in Group 4. No significant differences were observed in the Goslon Yardstick scores yielded by either type of procedure. The Goslon Yardstick score in relation to whether an osteotomy was performed in Phase II as part of orthodontic treatment was determined, focusing on the relationship between that score and the palatoplasty method used. A protraction facemask was used in patients undergoing the Perko procedure, which eliminated the need for an osteotomy at a future date. However, a protraction facemask was also used in patients undergoing the Wardill option, and those patients were likely to require an osteotomy. In other words, the results suggest that the type of palatoplasty selected will determine the effectiveness of any orthodontic appliances used.

Periodontal biotype: characteristic, prevalence and dimensions related to dental malocclusion

BACKGROUND

Knowledge of periodontal anatomy is essential when performing surgical and non-surgical procedures in the field of oral healthcare. Gingival biotype is often assessed for this purpose. The aim of this study was to assess the prevalence of the gingival biotypes in a group of patients and to evaluate if the gingival biotypes were related with the different types of Angle's classification of malocclusion.

METHODS

The study was performed on 76 volunteer patients (38 males, 38 females, mean age 14.7 years old). Gingival biotypes were assessed with the evaluation on the translucence of a periodontal probe through the gingival margin of the tooth during the probing, at the mid facial aspect of both maxillary central, lateral incisors and canine; on each patient, Angle's classification of malocclusion was also recorded.

RESULTS

The prevalence in the whole sample of thin gingival biotype was 43.4% and thick gingival biotype was 56.6%. The frequency of female with thin gingival biotype was significantly less respect to male patients (42.4% and 55.6%, respectively) while the thick gingival biotype was higher in the female respect to male patients (55.8% and 44.2%, respectively) (χ2=1.339, P=0.247). There was not a significant association between type of malocclusion and gingival biotype (P=0.143). There was however a prevalence of thick gingival biotype in patient with class II malocclusion and a slight prevalence of thin gingival biotype in patient with class I malocclusion.

CONCLUSIONS

No relationship was found between gingival biotypes and Angle's classification of malocclusion. In this sample, a higher prevalence of thick gingival biotype especially among female subjects was observed.

[The transverse dimension, an all-too-neglected factor]

A transverse dimension deficiency is most often the result of functional disorders. Poor tongue posture at rest and during function as well as digit-sucking give rise to deficiencies which are initially alveolar but which, with time, frequently end up becoming skeletal. The combination of functional rehabilitation and transverse dimension treatment is the best way to avoid many relapses. We need to monitor this anomaly closely, from diagnosis to retention. Otherwise, failure awaits us.

Dystrophic changes in masticatory muscles related chewing problems and malocclusions in Duchenne muscular dystrophy

Dysphagia in Duchenne muscular dystrophy (DMD) worsens with age, with increasingly effortful mastication. The aims of this study were to describe mastication problems in consecutive stages in a group of patients with DMD and to determine related pathophysiological aspects of masticatory muscle structure, tongue thickness, bite force and dental characteristics. Data from 72 patients with DMD (4.3 to 28.0 years), divided into four clinical stages, were collected in a cross sectional study. Problems with mastication and the need for food adaptations, in combination with increased echogenicity of the masseter muscle, were already found in the early stages of the disease. A high percentage of open bites and cross bites were found, especially in the later stages. Tongue hypertrophy also increased over time. Increased dysfunction, reflected by increasingly abnormal echogenicity, of the masseter muscle and reduced occlusal contacts (anterior and posterior open bites) were mainly responsible for the hampered chewing. In all, this study shows the increasing involvement of various elements of the masticatory system in progressive Duchenne muscular dystrophy. To prevent choking and also nutritional deficiency, early detection of chewing problems by asking about feeding and mastication problems, as well as asking about food adaptations made, is essential and can lead to timely intervention.

[IMPACT OF URANOSTAPHILOPLASTY ON QUALITY OF LIFE OF THE PATIENTS]

Abstract Retrospective analysis was conducted in 78 patients of various age, who suffered the inborn lip and palate fissura, for estimation of the patients quality of life after uranostaphiloplasty. The operations were performed on clinical base of The Oral Cavity Surgery and The Jaw-Facial Surgery Cathedra in Department of The Jaw-Facial Surgery of Clinical Medical Center (Baku). There was established, that application of uranostaphiloplasty procedure, as well as timely initiated rehabilitation, influences a further establishment of the patient personality. A timely refer to a speech therapeutist and the treatment began also have great significance for further establishment of the patient personality. Disorders of speech, incorrect bite hampers obtaining of education, working, interferes with a family creation, hampers the employment and worsens a quality of life.

Effects of Lower Third Molar Angulation and Position on Lower Arch Crowding

The role of the third molars in lower arch crowding has been debated for more than a century.

OBJECTIVES

The aim of this study was to determine the relationship between lower arch crowding and the presence of angulation and position of lower third molar.

METHODS AND MATERIALS

The measurements of the dental arch were made in 120 subjects aged 16 to 21 years, with average age to 18 years. The subjects were divided into two groups: Class I normal occlusion comprised 35 male and 25 female with mean age 18.87years, whereas Class I crowding comprised 27 males and 33 females with mean age 18.5 years. The dental pantomogram (DPT) were used to calculate the ratio of retromolar space (Ganss ratio), angulation of third molar to second molar and third molar to the base of the mandible.

RESULTS

The results showed that measurements of Ganss ratio, third molar angulation to the base of the mandible, and third molar to second molar inclination, was statistically significant between crowded and normal groups.

CONCLUSION

It can be concluded that there was a strong relationship between angulation and position of third molars and lower arch crowding. Key words: Third molars, angulation, lower arch, crowding

[Orthodontic treatment effect of on the condition of the upper airways]

INTRODUCTION

during the period of child growth airways and facial skeleton are developing in close relationship. Patients with upper dental arch narrowing and high gothic palet, tend to have narrowed nasal passages and are more vulnerable to violations of breathing during sleep - so-called obstructive sleep apnea (OSA, Obstructive Sleep Apnea), the occurrence of which is explained by a decrease of anteroposterior sizes of throat. The aim of the study was to evaluate the effect of orthodontic treatment in the period of mixed dentition on the state of the upper respiratory tract.

MATERIALS AND METHODS

there were examined 64 children (7-12 years) with class I malocclusion. Clinical examination was carried out according to the protocols of providing orthodontic care with assessment of the functional state of the maxillofacial region. Orthodontic correction had been carried with apparatus of Biobloc system. Before treatment and after its completion there had been performed morphometric analysis of dentition and assess patency of the upper airway by McNamara method.

RESULTS

prior to the beginning of orthodontic treatment in all patients had been found a significant decrease of upper and lower pharyngeal spaces 5.95±0.75mm, 8.1 8.}0.74 mm respectively (normal - 15-20mm and 11-14mm). After orthodontic treatment with Biobloc system the upper pharyngeal space increased in 2.5 times (P<0,01), lower pharyngeal space increased in 1.6 (p<0,01) times, and in average amounted to 13,3 ± 0,86 mm.

CONCLUSIONS

thus found that after orthodontic treatment with Biobloc apparatus along with the expansion of the alveolar arches of both jaws there is a significant positive effect of increasing the volume of the upper respiratory tract. Consequently, orthodontic treatment in the period of mixed dentition, stimulates the growth not only of the dental arches, but also greatly improves the development nazomaxillary complex and prevents apnea syndrome, that increases the level patient's health and life quality.

Relationships between Malocclusion, Body Posture, and Nasopharyngeal Pathology in Pre-Orthodontic Children

BACKGROUND

Malocclusion, body posture, and breathing pattern may be correlated, but this issue is still controversial. The aim of the study was to examine the relationship between the type of malocclusion, body posture, and nasopharyngeal obstruction in children aged 7-14 years.

MATERIAL AND METHODS

The study group comprised 94 patients aged 7-14 years (mean±SD: 11.9±2.1 years); 44 (46.8%) males and 50 (53.2%) females. All patients passed an examination performed by the same orthodontist (study model and cephalometric radiograph analysis), orthopedic surgeon (body posture examined from the front, side, and back), and otorhinolaryngologist (anterior and posterior rhinoscopy and pharyngoscopy) in a blind manner.

RESULTS

Postural disorders were observed in 72 (76.6%) patients. Hypertrophy of the adenoids was diagnosed in 54 (57.4%) patients, hypertrophy of the tonsils in 85 (90.3%), nasal septum deviation in 51 (54.3%), and allergic rhinitis in 19 (20.2%) patients. There was a statistically significant correlation between presence of kyphotic posture and a reduction in the SNB angle, representing sagittal position of the mandible. Also, there was a statistically significant association between kyphotic posture and nasopharyngeal obstruction (54.1% of patients with nasopharyngeal obstruction were kyphotic, compared with 25% of patients with no nasopharyngeal obstruction; p=0.02). Kyphotic posture and reduced SNB angle were more common among males.

CONCLUSIONS

We concluded that: 1) there was a significant association between the sagittal position of the mandible (SNB angle) and a kyphotic posture; 2) kyphotic posture was significantly more common among patients with nasopharyngeal obstruction.

Sagittal lip positions in different skeletal malocclusions: a cephalometric analysis

BACKGROUND

The objectives of this paper are to (1) study use of soft tissue analyses advocated by Steiner, Ricketts, Burstone, Sushner and Holdway to develop soft tissue cephalometric norms as baseline data for sagittal lip position in Northeast Chinese adult population, (2) compare the sagittal lip positions in different skeletal malocclusions and (3) compare the sagittal lip positions in Northeast Chinese adults with other reported populations.

METHODS

Lateral cephalometric radiographs of subjects were taken in natural head position. Radiographs were manually traced and five reference lines - Sushner, Steiner, Burstone, Holdway and Ricketts, were used. The linear distance between the tip of the lips and the five reference lines were measured. Statistical analysis was done using the Statistical Package for Social Sciences (SPSS) 21. Descriptive analysis was done for each variable for each subject. Coefficient of variation between lip positions as assessed by reference lines was determined. Post hoc Tukey's test was used for comparison of the mean cephalometric values of three skeletal malocclusions. The level of significance for the analysis was set at p < 0.05.

RESULTS

The findings showed significant difference in the sagittal lip positions in different skeletal malocclusions. There was variation in consistent reference line in each skeletal malocclusion. The S2 line was the most consistent reference line in skeletal class I and class II group. The B line was the most consistent line in skeletal class III. In skeletal class II group, upper lips were the most protrusive and lower lips were retrusive than in skeletal class I and class III groups. In case of skeletal class III group, upper lips were retrusive and lower lips were more protrusive than in skeletal class I and class II groups.

CONCLUSIONS

The sagittal lip positions were found to be associated with the skeletal malocclusion pattern. Northeast Chinese population has protrusive upper and lower lip in comparison to Caucasians. Each skeletal malocclusion group showed different preferable reference lines for analysis of sagittal lip position.

Shape variation and covariation of upper and lower dental arches of an orthodontic population

OBJECTIVES

This study aimed to quantify the patterns of shape variability and the extent and patterns of shape covariation between the upper and lower dental arch in an orthodontic population.

METHODS

Dental casts of 133 white subjects (61 males, 72 females; ages 10.6-26.6) were scanned and digitized in three dimensions. Landmarks were placed on the incisal margins and on the cusps of canines, premolars, and molars. Geometric morphometric methods were applied (Procrustes superimposition and principal component analysis). Sexual dimorphism and allometry were evaluated with permutation tests and age-size and age-shape correlations were computed. Two-block partial least squares analysis was used to assess covariation of shape.

RESULTS

The first four principal components represented shape patterns that are often encountered and recognized in clinical practice, accounting for 6-31 per cent of total variance. No shape sexual dimorphism was found, nevertheless, there was statistically significant size difference between males and females. Allometry was statistically significant, but low (upper: R(2) = 0.0528, P < 0.000, lower: R (2) = 0.0587, P < 0.000). Age and shape were weakly correlated (upper: R(2) = 0.0370, P = 0.0001, lower: R (2) = 0.0587, P = 0.0046). Upper and lower arches covaried significantly (RV coefficient: 33 per cent). The main pattern of covariation between the dental arches was arch width (80 per cent of total covariance); the second component related the maxillary canine vertical position to the mandibular canine labiolingual position (11 per cent of total covariance).

LIMITATIONS

Results may not be applicable to the general population. Age range was wide and age-related findings are limited by the cross-sectional design. Aetiology of malocclusion was also not considered.

CONCLUSIONS

Covariation patterns showed that the dental arches were integrated in width and depth. Integration in the vertical dimension was weak, mainly restricted to maxillary canine position.

Stability of anterior crossbite correction: a randomized controlled trial with a 2-year follow-up

OBJECTIVE

To compare and evaluate the stability of correction of anterior crossbite in the mixed dentition by fixed or removable appliance therapy.

MATERIAL AND METHODS

The subjects were 64 consecutive patients who met the following inclusion criteria: early to late mixed dentition, anterior crossbite affecting one or more incisors, no inherent skeletal Class III discrepancy, moderate space deficiency, a nonextraction treatment plan, and no previous orthodontic treatment. The study was designed as a randomized controlled trial with two parallel arms. The patients were randomized for treatment with a removable appliance with protruding springs or with a fixed appliance with multibrackets. The outcome measures were success rates for crossbite correction, overjet, overbite, and arch length. Measurements were made on study casts before treatment (T0), at the end of the retention period (T1), and 2 years after retention (T2).

RESULTS

At T1 the anterior crossbite had been corrected in all patients in the fixed appliance group and all except one in the removable appliance group. At T2, almost all treatment results remained stable and equal in both groups. From T0 to T1, minor differences were observed between the fixed and removable appliance groups with respect to changes in overjet, overbite, and arch length measurements. These changes had no clinical implications and remained unaltered at T2.

CONCLUSIONS

In the mixed dentition, anterior crossbite affecting one or more incisors can be successfully corrected by either fixed or removable appliances with similar long-term stability; thus, either type of appliance can be recommended.