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European Journal of Orthodontics Apr 2016This 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...
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.
Topics: Adolescent; Adult; Age Factors; Anatomic Landmarks; Bicuspid; Cephalometry; Child; Cross-Sectional Studies; Cuspid; Dental Arch; Female; Humans; Image Processing, Computer-Assisted; Male; Malocclusion; Malocclusion, Angle Class I; Malocclusion, Angle Class II; Mandible; Maxilla; Models, Dental; Molar; Overbite; Principal Component Analysis; Sex Factors; Tooth Crown; Vertical Dimension; Young Adult
PubMed: 25840587
DOI: 10.1093/ejo/cjv019 -
The Angle Orthodontist May 2022To examine relapse with thermoplastic retainers equipped with microsensors 1 year after treatment.
OBJECTIVES
To examine relapse with thermoplastic retainers equipped with microsensors 1 year after treatment.
MATERIALS AND METHODS
A total of 42 patients (29 females, 13 males) treated with four premolar extractions were included in this study. Thermoplastic appliances equipped with TheraMon microsensors (Handelsagentur Gschladt, Hargelsberg, Austria) were used to assess daily wear time (DWT), and the patients were monitored at 2-month intervals for a period of 12 months. At the end of the follow-up, the following two groups were formed based on the mean DWT: short wear time (SWT; <9 h/d) and long wear time (LWT; ≥9 h/d). Digital models were constructed before treatment (T0), at debonding (T1), and 6 months (T2) and 12 months (T3) after debonding. Little's Irregularity Index (LII) and the intercanine and intermolar widths, arch lengths, overjet, and overbite were calculated based on the digital models. Data were analyzed statistically.
RESULTS
Irregularity and overjet increased, whereas transverse measurements and arch lengths decreased with time in both groups. During the retention period, overbite decreased in the SWT group but increased in the LWT group. There were significant differences between groups only in mandibular irregularity. The LII values of the SWT group were significantly higher than those of the LWT group for the T1-T2 and T1-T3 time intervals (P < .05).
CONCLUSIONS
A mean DWT less than 9 hours/day was inadequate for controlling irregularity within clinically acceptable limits. A wear time of at least 9 h/d is recommended for the maintenance of mandibular anterior alignment.
Topics: Female; Humans; Male; Malocclusion, Angle Class II; Mandible; Orthodontic Retainers; Overbite; Recurrence
PubMed: 35076691
DOI: 10.2319/072221-578.1 -
The Angle Orthodontist Mar 2019This report illustrates successful nonsurgical orthodontic treatment of a hypodivergent adult patient with bilateral posterior scissors bite (Brodie bite) and excessive...
This report illustrates successful nonsurgical orthodontic treatment of a hypodivergent adult patient with bilateral posterior scissors bite (Brodie bite) and excessive overjet. A 26-year-old woman primarily reported maxillary incisor protrusion. She was diagnosed with Class ll division 1 malocclusion with skeletal Class I, short face, low mandibular plane angle and bilateral posterior scissors bite. A lingual arch with anterior bite block and posterior miniscrews with preadjusted edgewise appliances were used to improve the bilateral scissors bite. After achieving molar occlusion, the maxillary first premolars were extracted, and six miniscrews were used to improve the anterior-posterior and vertical discrepancies. After active treatment for 56 months, the convex facial profile with excessively protruded lips was improved and good interdigitation with ideal incisor relationship was achieved. Additionally, the irregular movements of the incisal path and the bilateral condyles during lateral excursion were improved. At 13 months of retention, a satisfactory facial profile, occlusion, and jaw movements were maintained. The treatment results suggest that miniscrews and fixed bite blocks were effective and efficient to facilitate correction of the bilateral scissors bite, excessive overjet, and vertical relationship correction in this nonsurgical orthodontic treatment.
Topics: Adult; Cephalometry; Dental Occlusion; Female; Humans; Malocclusion, Angle Class II; Malocclusion, Angle Class III; Open Bite; Orthodontic Anchorage Procedures; Overbite; Tooth Movement Techniques
PubMed: 30080111
DOI: 10.2319/111617-791.1 -
Indian Journal of Dental Research :... 2015Traumatic dental injury and malocclusion constitute a public health problem due to their high prevalence. Preventing or detecting such conditions, in any population, is...
CONTEXT
Traumatic dental injury and malocclusion constitute a public health problem due to their high prevalence. Preventing or detecting such conditions, in any population, is of paramount importance.
AIM
Assessing the association of anterior occlusal characteristics and dental trauma in preschool children.
SETTINGS AND DESIGN
A cross-sectional study was carried out with 2-6-year-old randomly selected by a sample calculation, resulting in 606 subjects
MATERIALS AND METHODS
A questionnaire to collect information about the sample (age, gender, and race) was sent to the children's parents. Two trained and calibrated examiners (Kappa 0.80) evaluated dental trauma according to criteria established by the World Health Organization. The following anterior occlusal characteristics were evaluated: Normal occlusion, anterior open bite, anterior crossbite, increased overjet (categorized as ≥3 mm), and increased overbite (categorized as ≥3 mm).
STATISTICAL ANALYSIS USED
The variables associations were assessed (odds ratio, Chi-square test, and logistic regression, P < 0.05) using statistical software (SPSS, version 16.0).
RESULTS
Dental trauma was observed in 20.8% and malocclusion in 48.6% of the children. There is an association between malocclusion and dental trauma (P = 0.01). Children with malocclusion have a 64% higher chance of suffering dental trauma. Increased overjet was the type of malocclusion related to a higher rate of tooth fracture (P < 0.01). Subjects with this type of malocclusion suffered tooth fractures three times more often than subjects with other malocclusion types.
CONCLUSIONS
There was association of dental trauma and malocclusion. Increased overjet was the most common malocclusion related to dental trauma. Preventive strategies are needed to reduce the rate of anterior malocclusion and, consequently, dental trauma in preschool children.
Topics: Child; Child, Preschool; Cross-Sectional Studies; Humans; Malocclusion; Risk Factors; Tooth Injuries
PubMed: 26481880
DOI: 10.4103/0970-9290.167630 -
Annals of Maxillofacial Surgery 2021The surgery-first approach provides immediate improvement in facial aesthetics in orthognathic cases with a shorter total treatment period.
THE RATIONALE
The surgery-first approach provides immediate improvement in facial aesthetics in orthognathic cases with a shorter total treatment period.
PATIENT CONCERNS
A 21-year-old male came with the chief complaint of protrusive lower front teeth and a large lower jaw. His main concern was aesthetics.
DIAGNOSIS
This was a case of skeletal Class III malocclusion with reverse overjet of 4 mm, overbite of 6 mm with a concave profile, and a protrusive chin.
TREATMENT
The patient was treated by bilateral sagittal split setback osteotomy of the mandible with surgery first approach via nonextraction therapy.
OUTCOME
After an active treatment of 15 months, improved facial profile, facial proportions, and a significant reduction of mandibular prognathism were much appreciated. The treatment results were stable after a 1-year follow-up of the treatment.
TAKE-AWAY LESSON
This case report highlights the utilization of nature's dental decompensation to achieve a desirable result, thereby attaining "more with less."
PubMed: 35265515
DOI: 10.4103/ams.ams_65_20 -
Root resorption during maxillary molar intrusion with clear aligners: a randomized controlled trial.The Angle Orthodontist Nov 2023To compare changes in maxillary molar root resorption, intrusion amount, dentoskeletal measures, and maximum bite force (MBF) between clear aligners (CA) and fixed... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
To compare changes in maxillary molar root resorption, intrusion amount, dentoskeletal measures, and maximum bite force (MBF) between clear aligners (CA) and fixed appliances with miniscrew (FM) during molar intrusion.
MATERIALS AND METHODS
Forty adults with anterior open bite were randomized into either CA or FM groups. Lateral cephalograms, cone-beam computed tomography (CBCT), and MBF were collected at pretreatment (T0) and 6 months of treatment (T1). Maxillary molar intrusion in FM were intruded by nickel-titanium (NiTi) closed-coil spring delivered force (150 grams/side) while clear aligners combined with squeezing exercise were performed in CA. Parametric tests were used for statistical analysis.
RESULTS
After 6 months of treatment, significant root resorption of 0.21-0.24 mm in CA and 0.38-0.47 mm in FM were found while maxillary molars were intruded 0.68 and 1.49 mm in CA and FM, respectively. CA showed significant less root resorption and intrusion than FM. Overbite, bite closing, and MBF increased significantly. CA showed significantly less overbite and SN-MP changes but more MBF increase than FM. MBF in CA was correlated with the amount of maxillary molar intrusion (r = 0.736, P < .05).
CONCLUSIONS
Maxillary molar intrusion and root resorption in CA were half the amount in FM in 6 months. The amount of maxillary molar root resorption was one-third of the intrusion distance. CA displayed less overbite increase and bite closing but more MBF increase than FM. MBF in CA was positively correlated with the molar intrusion amount.
Topics: Adult; Humans; Root Resorption; Overbite; Open Bite; Malocclusion, Angle Class II; Molar; Tooth Movement Techniques; Orthodontic Anchorage Procedures; Orthodontic Appliances, Removable; Maxilla
PubMed: 37922387
DOI: 10.2319/010723-14.1 -
Journal of Ayub Medical College,... 2020The role of malocclusion in the aetiology of TMDs has been discussed extensively in literature, however, the varied results from different studies have made it difficult...
BACKGROUND
The role of malocclusion in the aetiology of TMDs has been discussed extensively in literature, however, the varied results from different studies have made it difficult to reach a consensus. The objective of this study was to determine the association of dental characteristics and temporomandibular disorders (TMDs).
METHODS
This case-control study involved a total of 266 patients who were equally divided into 2 groups (TMD/Non-TMD) based on the score obtained from the Fonseca's questionnaire. Dental characteristics such as class of malocclusion, overjet, overbite, crossbite, and crowding were assessed. The Chi-square test was used to determine an association between each dental characteristic and TMD. Odds ratios were calculated using simple and multiple logistic regression.
RESULTS
Significant associations were found between crowding, crossbites, and molar relationships in males. Simple logistic regression showed significant associations for class II malocclusion (OR=0.56, p=0.024) and crowding (OR=0.35, p<0.001) with TMD. Multiple logistic regression showed significant associations for crowding (p<0.001) and class III malocclusion (p=0.002).
CONCLUSIONS
Male patients with dental characteristics such as improper molar relationships, crossbites, and crowding should seek orthodontic treatment to prevent the onset of TMDs. Higher odds of TMD were found in patients with Angle's class III malocclusion.
Topics: Case-Control Studies; Female; Humans; Male; Malocclusion; Temporomandibular Joint Disorders
PubMed: 33225650
DOI: No ID Found -
Progress in Orthodontics Dec 2016The normative orthodontic treatment need, established by dental professionals during the dental appointment, becomes ineffective when it does not evaluate all the...
BACKGROUND
The normative orthodontic treatment need, established by dental professionals during the dental appointment, becomes ineffective when it does not evaluate all the factors that influence the decision-making process, including individuals' perception and satisfaction with their dental appearance. Therefore, the purpose of this study was to investigate the perception of children and their mothers as regards orthodontic treatment need and satisfaction with dental aesthetics and test if these variables are associated with the objective orthodontic treatment needs, assessed by the Dental Aesthetic Index (DAI).
METHODS
A cross-sectional study was conducted on 308 children aged 12 years, and their mothers were randomly selected by cluster sampling (primary schools). The variables "orthodontic treatment need," "satisfaction with chewing," and "dental appearance" were assessed by means of a questionnaire. The questions were answered individually at school or home, in cases of children or mothers, respectively. DAI was assessed to make an objective clinical assessment. The variables were dichotomized and statistically analyzed by the chi-square and Fisher's exact tests, contingency coefficient C, and logistic regression.
RESULTS
The results of the clinical evaluation (DAI) were statistically associated with the perception of orthodontic treatment need and satisfaction with dental appearance in children (p ≤ 0.01). However, no association was observed with regard to satisfaction with chewing and DAI (p = 0.10). The children's perception of orthodontic treatment need and satisfaction with the appearance of their teeth was statistically associated (p ≤ 0.01) with their mothers' perception. Maxillary overjet, maxillary and mandibular misalignment, and dental crowding were associated with the orthodontic treatment need by children and their mothers, with p value -0.05 and 5 % level of significance. Maxillary overjet was a significant predictor for the perception of orthodontic treatment need in children (OR 1.86, 95 % CI 0.98-3.55) and mothers (OR 3.02, 95 % CI 1.54-5.92).
CONCLUSIONS
Children and parents realize the need for orthodontic treatment according to the different types of malocclusion, as noted in the association between orthodontic treatment need and dental appearance perceived by children and their mothers, which was also observed-with low correlation-with regard to DAI.
Topics: Adolescent; Attitude to Health; Bone Malalignment; Brazil; Child; Cross-Sectional Studies; Esthetics, Dental; Female; Health Services Needs and Demand; Humans; Index of Orthodontic Treatment Need; Male; Malocclusion; Mandible; Mastication; Maxilla; Mothers; Needs Assessment; Orthodontics, Corrective; Overbite; Perception; Personal Satisfaction; Pilot Projects; Psychology, Adolescent; Schools; Self Concept; Surveys and Questionnaires
PubMed: 27747529
DOI: 10.1186/s40510-016-0149-6 -
Dental Press Journal of Orthodontics 2020To evaluate the prevalence and severity of malocclusion in children suffering from β-thalassemia and to assess orthodontic treatment need using Grainger's Treatment...
OBJECTIVE
To evaluate the prevalence and severity of malocclusion in children suffering from β-thalassemia and to assess orthodontic treatment need using Grainger's Treatment Priority Index (TPI) and index of orthodontic treatment need (IOTN)-dental health component (DHC).
METHODS
A cross-sectional study was conducted on 200 transfusion-dependent children diagnosed with homozygous β-thalassemia and 200 healthy school children aged 11-17 years. The TPI and IOTN-DHC data was recorded for both groups. Total TPI score for each subject was calculated and graded according to malocclusion severity estimate (MSE). Independent sample t-test was used to compare mean TPI scores, overjet and overbite between thalassemic and healthy children. Chi-square test was used to compare the frequency of IOTN-DHC grades, Angle's classification, and MSE grades between thalassemic and healthy children.
RESULTS
The most prevalent malocclusion was Class I in normal children (67.5%) and Class II in thalassemic children (59%). The mean overjet and overbite were significantly (p<0.001) greater in thalassemic children than in healthy children. Severe tooth displacements were 3.5 times greater in thalassemic children, compared to controls. A greater proportion of thalassemic children were in IOTN grades 3 and 4, compared to the controls (p<0.001). MSE grades 4 and 5 were significantly (p<0.001) more prevalent in thalassemic children, compared to the controls.
CONCLUSION
There is a high prevalence of Angle's Class II malocclusion in thalassemic children. Majority of these children are categorized in higher grades of IOTN-DHC and TPI-MSE, showing a great severity of malocclusion and high orthodontic treatment needs.
Topics: Adolescent; Child; Cross-Sectional Studies; Humans; Index of Orthodontic Treatment Need; Malocclusion; Malocclusion, Angle Class II; Orthodontics, Corrective; beta-Thalassemia
PubMed: 33503121
DOI: 10.1590/2177-6709.25.6.26.e1-9.onl -
Journal of Dental Research, Dental... 2023Posterior intrusion with skeletal anchorage is one of the effective methods in the treatment of anterior open bite. Knowing the effects of posterior intrusion, the... (Review)
Review
BACKGROUND
Posterior intrusion with skeletal anchorage is one of the effective methods in the treatment of anterior open bite. Knowing the effects of posterior intrusion, the amount of possible molar intrusion using skeletal anchorage, and its impact on clinical and cephalometric indicators can help the clinician choose the optimal treatment method, especially in borderline surgical cases.
METHODS
In this systematic review, a series of articles were collected through a systematic search in databases, and the titles and summaries of all these articles were reviewed. After removing the irrelevant articles, the full texts of the related articles were read carefully, and their validity was evaluated. Only RCTs and observational studies that complied with PICO questions were included. The Cochrane Risk of Bias 2.0 (RoB 2), ROBINS-I, and GRADE were used to assess the risk of bias in the included studies. The relevant information on selected articles was extracted, and a meta-analysis was performed with Review Manager 5.4 software.
RESULTS
The meta-analysis revealed a significant average molar intrusion of 2.89 mm using temporary anchorage devices (TADs). A subgroup analysis showed that miniplates achieved greater intrusion (3.29 mm) compared to miniscrews (2.25 mm) (=0.03). The level of applied force did not significantly affect the degree of intrusion. Dental parameters such as overbite and overjet were notably altered, with overbite increasing by 4.81 mm and overjet decreasing by 2.06 mm on average. As for the skeletal cephalometric characteristics, SNB, ANB, and SN-Pog increased while mandibular plane angle and lower anterior facial height (LAFH) decreased, and these changes were significant. Meanwhile, SNA and palatal angle changes were not significant.
CONCLUSION
TADs have proved effective in achieving significant intrusion of maxillary molars, leading to marked improvements in dental and skeletal characteristics in patients with open bite malocclusion. Miniplates proved more effective in achieving greater intrusion.
PubMed: 38584993
DOI: 10.34172/joddd.2023.40754