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1.
Am J Orthod Dentofacial Orthop ; 156(2): 248-256.e2, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31375235

RESUMEN

INTRODUCTION: The treatment options for adults with increased overbite are limited to dentoalveolar changes that camouflage the condition. Because of high relapse tendency, defining the problem area is important when creating a treatment plan. This study aimed to evaluate dentoskeletal morphology in skeletal Class I and II anomalies associated with Angle Class I, Class II Division 1 (Class II/1), and Class II Division 2 (Class II/2) malocclusions with increased overbite compared with normal occlusion. METHODS: Pretreatment cephalograms of 306 patients (131 men, 175 women; overall ages 18-45 years) were evaluated. Four groups were constructed. Three groups had increased overbite (>4.5 mm): group 1 (n = 96) skeletal Class I (ANB = 0.5°-4°), group 2 (n = 85) skeletal Class II (ANB >4.5°) with Class II/1; and group 3 (n = 79) skeletal Class II with Class II/2 malocclusion. Group 4 as a control (n = 46) skeletal Class I normal overbite. Dental and skeletal characteristics of the groups were compared by sex. For statistical evaluations, analysis of variance followed by Tukey post hoc, Mann-Whitney U, and Kruskall-Wallis tests were used. Additionally correlation coefficients between overbite and skeletal/dental parameters were calculated. RESULTS: Between sexes, with regard to skeletal parameters, the men had greater values in millimetric measurements, and the women had higher SN/GoGn values. Maxillary/mandibular molar heights and the mandibular incisor heights were higher in men. In group 1, decreased lower anterior facial height (LAFH), retrusive mandibular incisors, and increased interincisal degree were determined. The maxillary molars were intrusive, whereas the vertical position of the mandibular molars and incisors in both jaws were normal. In group 2, retrognathic mandible, increased LAFH and mandibular plane angle, extrusive maxillary/mandibular incisors, protrusive mandibular incisors, and decreased interincisal degree were found. In group 3, decreased LAFH, increased interincisal degree, and retrusive incisors in both jaws were determined. There were significant negative correlations between SN/GoGN, palatal plane, and overbite in group 2 and between ANS-SN and overbite in group 3, and positive correlation between interinsical angle and overbite in all increased overbite groups. CONCLUSIONS: Dental morphology seems to be the main factor of increased overbite. Differences between groups were related primarily to inclinations and vertical positions of the incisors, rather than molar positions.


Asunto(s)
Maloclusión Clase II de Angle/patología , Maloclusión Clase I de Angle/patología , Sobremordida/epidemiología , Sobremordida/patología , Adolescente , Adulto , Análisis de Varianza , Puntos Anatómicos de Referencia , Cefalometría , Femenino , Humanos , Incisivo/patología , Masculino , Maloclusión de Angle Clase III/patología , Mandíbula/patología , Maxilar/patología , Persona de Mediana Edad , Diente Molar/patología , Retrognatismo/patología , Factores Sexuales , Turquia , Adulto Joven
2.
Am J Orthod Dentofacial Orthop ; 155(4): 473-481, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30935602

RESUMEN

INTRODUCTION: The objective was to study the growth spurt of Class I subjects, focusing on the ability to predict the peak of the growth spurt of the maxillary (Co-A) and mandibular (Co-Pog) lengths from the maturational changes of the cervical vertebrae. METHODS: The longitudinal lateral cephalographs of 14 males (ages, 10-15 years) and 12 females (ages, 9-14 years) were selected from the Craniofacial Growth Studies Legacy Collection of the American Association of Orthodontists Foundation. The cephalographs were taken at regular 1-year intervals. A cervical vertebral maturation (CVM) method that divided skeletal maturation into 6 stages was used for growth prediction. Growth increments calculated for the annual age intervals were used to examine the diagnostic performance of the CVM method. RESULTS: In males, the most peaks for Co-Pog were detected in the CVM3-CVM4 interval in 7 males (50%); for Co-A, the most peaks were found in the CVM2-CVM3 interval in 7 males (50%). In females, the most peaks for both Co-Pog and Co-A were seen in the CVM2-CVM3 interval in 7 females (58%) and in 6 females (50%), respectively. The fewest peaks were detected in CVM4-CVM5 for both males and females. CONCLUSIONS: In Class I subjects with balanced anteroposterior jaw relationships, presence of CVM3 would indicate the peak of the growth spurt, and CVM2 would mean that the peak has not yet arrived. During CVM2, the shapes of cervical vertebrae 3 and 4, whether trapezoid or horizontal rectangular, would indicate whether the subject is in the early CVM2 or is about to be in CVM3.


Asunto(s)
Huesos Faciales/crecimiento & desarrollo , Maloclusión Clase I de Angle/patología , Cráneo/crecimiento & desarrollo , Adolescente , Cefalometría , Vértebras Cervicales/crecimiento & desarrollo , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Mandíbula/crecimiento & desarrollo , Maxilar/crecimiento & desarrollo
3.
Int Orthod ; 17(1): 151-158, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30772351

RESUMEN

OBJECTIVE: Comparison of dental measurements between conventional plaster models, digital models obtained by impression scanning and plaster model scanning. PURPOSE: To evaluate and to compare the accuracy and reliability of tooth size, arch width and Bolton tooth size discrepancy measurements on 3 Dimensional (3D) digital models obtained by plaster dental model scanning, dental impression scanning and conventional plaster models. MATERIAL AND METHODS: This study was carried out on the maxillary and mandibular dental models of 25 patients with Angle Class I molar relationship and minimal crowding. Mesio-distal dimensions of the teeth, intercanine and intermolar arch width, and Bolton tooth size discrepancy measurements were calculated by conventional methods on plaster models, digital methods and on 3D models obtained from plaster model scanning and impression scanning. All measurements were repeated after three weeks for each of the investigated methods. Reliability of measurements was evaluated by Dahlberg formula and Pearson Correlation Coefficient. Comparisons of dental measurements between three methods were achieved with ANOVA Test. RESULTS: The repeated measurements were highly correlated for all methods. Method error was found within clinically acceptable limits. There was no significant difference between dental measurements on plaster dental models, digital models obtained from plaster dental model scanning and dental impression scanning. Results showed the methods being highly reliable and accurate for tooth size, arch width and Bolton analysis at total and anterior proportion calculation. CONCLUSION: Digital measurements of tooth size, arch width and Bolton tooth size discrepancy on digital models obtained from plaster dental model scanning and dental impression scanning showed high accuracy and reliability. There was no significant difference between the three methods for dental measurements.


Asunto(s)
Diseño Asistido por Computadora , Técnica de Impresión Dental , Modelos Dentales , Odontometría/métodos , Arco Dental , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Maloclusión/clasificación , Maloclusión/diagnóstico , Maloclusión/patología , Maloclusión Clase I de Angle/diagnóstico , Maloclusión Clase I de Angle/patología , Mandíbula , Maxilar , Ortodoncia , Reproducibilidad de los Resultados , Diente/patología
4.
Cranio ; 37(4): 214-222, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29327661

RESUMEN

OBJECTIVE: To assess changes in the tongue and hyoid bone positions and airway dimensions after maxillary protraction using lateral cephalograms. METHODS: Lateral cephalograms were obtained before (C0) and after (C1) an observation period for untreated children with skeletal Class I malocclusion and before (T0), immediately after (T1), and one year after (T2) maxillary protraction in children with skeletal Class III malocclusion. Cephalometric measurements were compared between the time points in both patient groups. RESULTS: Immediately after maxillary protraction, the tongue moved superiorly and the nasopharyngeal and superior oropharyngeal airway dimensions increased. No significant changes in the middle or inferior oropharyngeal airway dimensions or in the hyoid bone position were noted after treatment. CONCLUSIONS: Maxillary protraction improved tongue posture and modified the nasopharyngeal and superior oropharyngeal airway dimensions in patients with skeletal Class III malocclusion. Consequently, maxillary protraction may restore the intra- and extraoral balance and improve respiratory function.


Asunto(s)
Cefalometría/métodos , Hueso Hioides/patología , Maloclusión de Angle Clase III/patología , Maloclusión de Angle Clase III/rehabilitación , Maloclusión Clase I de Angle/patología , Maloclusión Clase I de Angle/rehabilitación , Maxilar , Faringe/patología , Lengua/patología , Tracción/métodos , Niño , Aparatos de Tracción Extraoral , Femenino , Humanos , Masculino , Maloclusión Clase I de Angle/diagnóstico , Maloclusión de Angle Clase III/diagnóstico , Factores de Tiempo , Tracción/instrumentación
5.
Orthod Craniofac Res ; 22(1): 9-15, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30421852

RESUMEN

OBJECTIVES: To clarify the associations among tongue volume, hyoid position, airway volume and maxillofacial form using cone beam computed tomography (CBCT) data for children with Class-I, Class-II and Class-III malocclusion. SETTING AND SAMPLE POPULATION: Sixty children (mean age, 9.2 years) divided into Class-I, Class-II and Class-III malocclusion groups according to the A-nasion-B angle. MATERIAL AND METHODS: Cone beam computed tomography was used for three-dimensional reconstruction of the maxillofacial region and airway. The hyoid position and the tongue, airway and oral cavity volumes were evaluated. Upper airway ventilation status was calculated using computational fluid dynamics. The groups were compared using analysis of variance and Kruskal-Wallis tests; relationships among the parameters were assessed using Pearson's and Spearman's rank correlation tests. RESULTS: The tongue volume was larger in Class-III patients (50.63 cm3 ) than in Class-I patients (44.24 cm3 ; P < 0.05). The hyoid position was lower (49.44 cm), and anatomical balance (AB; tongue volume/oral cavity volume; 85.06%) was greater in Class-II patients than in Class-I patients (46.06 cm, 80.57%, respectively; P < 0.05 for both). The hyoid height showed a positive correlation with AB (r = 0.614; P < 0.001). CONCLUSIONS: Children with Class-III malocclusion have large tongue volumes and small AB; the reverse is true for children with Class-II malocclusion. The hyoid position is closely associated with AB in children with malocclusion.


Asunto(s)
Hueso Hioides/patología , Maloclusión de Angle Clase III/patología , Maloclusión Clase II de Angle/patología , Maloclusión Clase I de Angle/patología , Nasofaringe/patología , Lengua/patología , Niño , Tomografía Computarizada de Haz Cónico , Cara/diagnóstico por imagen , Cara/patología , Femenino , Humanos , Hueso Hioides/diagnóstico por imagen , Imagenología Tridimensional , Masculino , Maloclusión Clase I de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión de Angle Clase III/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Maxilar/patología , Nasofaringe/diagnóstico por imagen , Estudios Retrospectivos , Lengua/diagnóstico por imagen
6.
J Contemp Dent Pract ; 19(6): 712-718, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29959301

RESUMEN

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.


Asunto(s)
Asimetría Facial/diagnóstico , Maloclusión/patología , Adolescente , Adulto , Cefalometría , Niño , Cara/patología , Asimetría Facial/patología , Femenino , Humanos , Maxilares/patología , Masculino , Maloclusión Clase I de Angle/patología , Maloclusión Clase II de Angle/patología , Maloclusión de Angle Clase III/patología , Adulto Joven
7.
BMC Oral Health ; 18(1): 109, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29921259

RESUMEN

BACKGROUNDS: The occlusal registration of virtual models taken by intraoral scanners sometimes shows patterns which seem much different from the patients' occlusion. Therefore, this study aims to evaluate the accuracy of virtual occlusion by comparing virtual occlusal contact area with actual occlusal contact area using a plaster model in vitro. METHODS: Plaster dental models, 24 sets of Class I models and 20 sets of Class II models, were divided into a Molar, Premolar, and Anterior group. The occlusal contact areas calculated by the Prescale method and the virtual occlusion by scanning method were compared, and the ratio of the molar and incisor area were compared in order to find any particular tendencies. RESULTS: There was no significant difference between the Prescale results and the scanner results in both the molar and premolar groups (p = 0.083 and 0.053, respectively). On the other hand, there was a significant difference between the Prescale and the scanner results in the anterior group with the scanner results presenting overestimation of the occlusal contact points (p < 0.05). In Molars group, the regression analysis shows that the two variables express linear correlation and has a linear equation with a slope of 0.917. R2 is 0.930. Groups of Premolars and Anteriors had a week linear relationship and greater dispersion. CONCLUSIONS: Difference between the actual and virtual occlusion revealed in the anterior portion, where overestimation was observed in the virtual model obtained from the scanning method. Nevertheless, molar and premolar areas showed relatively accurate occlusal contact area in the virtual model.


Asunto(s)
Modelos Dentales , Oclusión Dental , Imagenología Tridimensional , Maloclusión Clase II de Angle/patología , Maloclusión Clase I de Angle/patología , Adulto , Humanos , Técnicas In Vitro , Maloclusión Clase I de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/diagnóstico por imagen , Interfaz Usuario-Computador
8.
J Contemp Dent Pract ; 19(5): 515-520, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29807960

RESUMEN

AIM: The purpose of this study was to assess the arch width, transverse discrepancy, and transverse interarch ratio for class I malocclusion sample, with and without crossbite, in permanent dentition stage. MATERIALS AND METHODS: Records of class I malocclusion patients with minimal crowding and spacing with and without posterior crossbite were selected. Each group consisted of 40 pairs of dental casts (20 males and 20 females). Arch widths were measured for the canine, first, and second premolars, and first permanent molars using the buccal approach. Means and standard deviations (SDs) of dental arch widths were measured for the maxillary and mandibular arches, and the interarch width ratio was calculated. RESULTS: There was a highly significant difference between the noncrossbite and crossbite groups regarding the maxillary width, p < 0.001. However, no differences were found between groups for the mandibular widths, p > 0.01. There were also significant differences between both groups for the intercanine, first and second premolars, and first molar ratios, p < 0.001. CONCLUSION: This new simple method showed that a transverse maxillary-mandibular ratio of 1:1.1 is ideal. A ratio less than 1:0.9 will indicate the presence of crossbite. CLINICAL SIGNIFICANCE: The interarch ratio significantly aids in orthodontic treatment planning in patients requiring maxillary expansion and/or surgical cases.


Asunto(s)
Cefalometría/métodos , Arco Dental/patología , Maloclusión Clase I de Angle/patología , Diente Premolar , Diente Canino , Dentición Permanente , Femenino , Humanos , Masculino , Mandíbula/patología , Maxilar/patología , Diente Molar
9.
Angle Orthod ; 88(5): 552-559, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29809053

RESUMEN

OBJECTIVES: The aim of this study was to assess three-dimensionally the upper airway changes following functional appliance treatment in growing Class II patients. MATERIALS AND METHODS: Pre-and post-treatment Cone beam computed tomography scans of 20 patients (age range: 9 to 12; mean: 11.4 ± 1.0 years) were retrieved from the list of patients previously treated with functional appliances in the Postgraduate Clinic at the Section of Orthodontics, Aarhus University, Denmark. Total and partial volumes of the upper airway (ie, lower nasopharynx, velopharynx, and oropharynx) were calculated. To rule out the effect of growth, the changes in the functional appliance group were compared to an age-matched Class I group of 18 patients (age range: 8 to 14; mean: 11.8 ± 1.4 years). RESULTS: In the functional appliance group, all the partial and total volumes were significantly larger at the end of treatment when compared to the start of treatment ( P < .003). On the other hand, when comparing the changes for the total and partial volumes of the upper airway in the functional appliance group with the Class I group, a statistical difference was seen only for the oropharynx ( P = .022) and total volume ( P = .025), with the functional appliance group showing a larger volume increment. CONCLUSIONS: An increase in the upper airway volume was found after treatment with functional appliances. This difference was mainly related to the changes at the oropharynx level, which differed significantly from what was observed in the Class I group.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Avance Mandibular , Aparatos Ortodóncicos Funcionales , Faringe/patología , Adolescente , Niño , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Hipofaringe/diagnóstico por imagen , Hipofaringe/patología , Imagenología Tridimensional , Masculino , Maloclusión Clase I de Angle/patología , Maloclusión Clase II de Angle/patología , Avance Mandibular/métodos , Orofaringe/diagnóstico por imagen , Orofaringe/patología , Faringe/diagnóstico por imagen , Estudios Retrospectivos
10.
Indian J Dent Res ; 29(2): 137-143, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29652003

RESUMEN

Introduction:: Soft-tissue analysis has become an important component of orthodontic diagnosis and treatment planning. Photographic evaluation of an orthodontic patient is a very close representation of the appearance of the person. The previously established norms for soft-tissue analysis will vary for different ethnic groups. Thus, there is a need to develop soft-tissue facial profile norms pertaining to Indian ethnic groups. Aim and Objectives:: The aim of this study is to establish the angular photogrammetric standards of soft-tissue facial profile for Indian males and females and also to compare sexual dimorphism present between them. Materials and Methods: The lateral profile photographs of 300 random participants (150 males and 150 females) between ages 18 and 25 years were taken and analyzed using FACAD tracing software. Inclusion criteria were angles Class I molar occlusion with acceptable crowding and proclination, normal growth and development with well-aligned dental arches, and full complements of permanent teeth irrespective of third molar status. This study was conducted in Indian population, and samples were taken from various cities across India. Descriptive statistical analysis was carried out, and sexual dimorphism was evaluated by Student's t-test between males and females. Results: The results of the present study showed statistically significant (P < 0.05) gender difference in 5 parameters out of 12 parameters in Indian population. Conclusion: In the present study, soft-tissue facial measurements were established by means of photogrammetric analysis to facilitate orthodontists to carry out more quantitative evaluation and make disciplined decisions. The mean values obtained can be used for comparison with records of participants with the same characteristics by following this photogrammetric technique.


Asunto(s)
Cara/anatomía & histología , Adolescente , Adulto , Cefalometría , Femenino , Humanos , India , Masculino , Maloclusión Clase I de Angle/patología , Fotogrametría , Fotografía Dental , Factores Sexuales , Adulto Joven
11.
BMC Oral Health ; 18(1): 45, 2018 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-29548316

RESUMEN

BACKGROUND: The purpose of this study was to determine and compare the shapes, sizes, and bridging of the sella turcica in patients with different skeletal patterns and genders. METHODS: It was a cross-sectional comparative study. The samples were divided into three groups according to the skeletal pattern viz. Class I, Class II and Class III, and each group consisted of 40 samples (20 males and 20 females). The lateral cephalograms were traced and the sella turcica was assessed for its size, shape, and bridging. RESULTS: The mean length, anteroposterior diameter and depth of sella turcica were 8.13 ± 2.03 mm, 9.60 ± 1.43 mm and 6.40 ± 1.21 mm respectively. The mean length of sella turcica was 7.91 ± 1.52 mm in Class I, 7.32 ± 1.62 mm in Class II and 9.16 ± .2.42 in Class III skeletal pattern; anteroposterior diameter was 9.30 ± 1.02 mm in Class I, 9.15 ± 1.28 mm in Class II and 10.35 ± 1.64 mm in Class III skeletal pattern; and the depth was 6.40 ± 0.92 mm in Class I, 6.07 ± 1.01 mm in Class II and 6.74 ± .1.54 mm in Class III skeletal pattern. There were significant differences in length and anteroposterior diameter and sella turcica between Class I, Class II and Class III skeletal patterns (p = 0.01), (p = 0.01) respectively. There was no significant difference in size of sella turcica between different genders and age groups. Sixty percent of the patients studied had normal Sella morphology. Partial Sella turcica bridging and Sella turcica bridging was seen in this study in 23.33% and 11.67% of patients respectively. CONCLUSION: Sixty percent of the patients had normal sella turcica. There were significant differences in lengths and anteroposterior diameters among Class I, Class II and Class III patients. The larger size was present in skeletal Class III patients.


Asunto(s)
Maloclusión/patología , Silla Turca/patología , Adolescente , Adulto , Factores de Edad , Estudios Transversales , Femenino , Humanos , Masculino , Maloclusión Clase I de Angle/patología , Maloclusión Clase II de Angle/patología , Maloclusión de Angle Clase III/patología , Radiografía , Silla Turca/diagnóstico por imagen , Factores Sexuales , Adulto Joven
12.
Angle Orthod ; 88(2): 195-201, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29215300

RESUMEN

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.


Asunto(s)
Maloclusión/etiología , Anomalías Dentarias/complicaciones , Adolescente , Adulto , Cefalometría , Niño , Femenino , Humanos , Masculino , Maloclusión/diagnóstico por imagen , Maloclusión/patología , Maloclusión Clase I de Angle/etiología , Maloclusión Clase I de Angle/patología , Maloclusión Clase II de Angle/etiología , Maloclusión Clase II de Angle/patología , Maloclusión de Angle Clase III/etiología , Maloclusión de Angle Clase III/patología , Radiografía Dental , Radiografía Panorámica , Anomalías Dentarias/diagnóstico por imagen , Anomalías Dentarias/patología , Diente Impactado/complicaciones , Diente Impactado/patología , Adulto Joven
13.
Am J Orthod Dentofacial Orthop ; 153(1): 36-45, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29287646

RESUMEN

INTRODUCTION: Our objective was to investigate craniofacial morphology in women with Class I occlusion and maxillary anterior crowding (MxAC) with bilateral palatal displacement of the lateral incisors and facial displacement of the canines. METHODS: Thirty-three women with normal occlusion (mean age, 20.7 ± 2.3 years) were selected as the control group, and 33 women with severe MxAC (mean age, 23.3 ± 3.8 years) with bilateral palatal and facial displacement of the lateral incisors and canines, respectively, were selected as the MxAC group. Mesiodistal tooth crown diameter, arch length discrepancy, facial-palatal displacement of lateral incisors and canines, and dental arch dimensions were measured. Fourteen skeletal and 10 dental cephalometric measurements were made. Medians, interquartile ranges, means, and standard deviations were calculated for each parameter, and the nonparametric Mann-Whitney U test (P <0.05) was used to compare the 2 groups. RESULTS: Compared with the control group, the MxAC group showed a significantly wider angle (P <0.05) and shorter length (P <0.01) in the cranial base, a smaller sagittal maxillary base (P <0.01), and a hyperdivergent skeletal pattern (P <0.01 and P <0.05). CONCLUSIONS: Women with Class I occlusion and severe MxAC exhibited a significantly wider angle and shorter length in the cranial base, a smaller sagittal maxillary base, and a hyperdivergent skeletal pattern. These skeletal and dental characteristics and cranial base dysmorphology may be helpful as potential indicators for orthodontic treatment with extractions.


Asunto(s)
Cefalometría , Cara/anatomía & histología , Maloclusión Clase I de Angle/patología , Cráneo/anatomía & histología , Estudios Transversales , Diente Canino , Femenino , Humanos , Incisivo , Maxilar , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto Joven
14.
Eur J Orthod ; 40(2): 206-213, 2018 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-29016736

RESUMEN

Aim: To investigate the long-term (≥15 years) post-treatment (Tx) occlusal changes and outcome quality after Class II:1 Tx. Subjects and Methods: Herbst-MBA Tx had been performed at age 12.8 ± 2.7 years in 119 patients. A recall was conducted and study models from before and after active Tx, after retention as well as after recall were evaluated using standard occlusal variables and the PAR index. These data were compared to 31 untreated Class I controls. Results: 52 out of 119 patients could be located and participated at 33.6 ± 3.1 years. Compared to the 67 patients who did not participate in the recall, the pre- and post-Tx occlusal data of the participants did not differ systematically; however, the PAR scores were higher by 3.0-4.7 points at all times. Pre-Tx, the mean values of the 52 participants were: PAR = 27.2 ± 7.6, Class II molar relationship (MR) = 0.7 cusp widths (cw), overjet = 8.2 mm, overbite = 4.1 mm. After Tx, the PAR score was 3.4 ± 2.2. A Class I MR (0.0 ± 0.1 cw) with normal overjet (2.3 ± 0.7 mm) and overbite (1.3 ± 0.7 mm) existed. At recall, a mild PAR score increase to 8.2 ± 5.5 points had occurred; this was mainly due to increased overjet and overbite values (3.6 ± 1.1 and 2.8 ± 1.6 mm) while the MR was stable (0.0 ± 0.2 cw). For all these variables, similar findings were made in the untreated controls. Conclusion: The occlusal outcome of Class II:1 Tx showed very good long-term stability. While mild changes occur post-Tx, the long-term result is similar to untreated Class I controls.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Adolescente , Cefalometría/métodos , Niño , Oclusión Dental , Femenino , Estudios de Seguimiento , Humanos , Masculino , Maloclusión Clase I de Angle/patología , Maloclusión Clase II de Angle/patología , Aparatos Ortodóncicos Funcionales , Ortodoncia Correctiva/instrumentación , Ortodoncia Correctiva/métodos , Sobremordida/terapia , Resultado del Tratamiento
15.
Prog Orthod ; 18(1): 44, 2017 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-29250718

RESUMEN

BACKGROUND: In the long-lasting debate of extraction versus non-extraction treatment, the impact of extractions on the skeletal vertical dimension remains rather unclear. The aim of this retrospective research study was to obtain a bias-free sample of morphologically similar borderline patients treated with or without extraction of the four first premolars and to retrospectively evaluate the vertical changes that occurred. METHODS: A borderline sample of 83 patients, 41 treated with four first premolar extractions and 42 treated without, was obtained by means of discriminant analysis applied to a previously investigated parent sample of 542 class I patients. The pretreatment and posttreatment cephalometric radiographs were analyzed digitally, and seven measurements were assessed for vertical skeletal changes. Also, average tracings between the two treatment groups were evaluated using the Procrustes superimposition method. RESULTS: The variables of SN to Go-Gn and Y-axis showed adjusted intergroup differences of - 0.91° and - 1.11° (P = 0.04). Comparing the mean intra-group differences of all the variables simultaneously, a significant difference was found between the two treatment groups (overall P value = 0.04). In the extraction group, only the gonial angle showed a significant decrease (P = 0.01) while the overall P value evaluating the intra-group differences between pre- and posttreatment was significant (overall P value < 0.01). In the non-extraction group, the variable of N-ANS/N-Me showed a significant decrease (P = 0.02) and the overall P value evaluating the intra-group differences between pre- and posttreatment was also significant (overall P value < 0.01). Differences in treatment duration were assessed using a log-normal model and showed that extraction treatment lasted significantly longer than non-extraction treatment (P < 0.01). CONCLUSIONS: The borderline group of patients identified by the discriminant analysis exhibited similar morphological characteristics at treatment's onset; therefore, the posttreatment changes could safely be attributed to the choice of extraction or non-extraction treatment and not to pre-existing differences. Treatment choice had an impact on the patients' vertical skeletal dimensions. Patients treated with four first premolar extractions showed a slight decrease in the vertical skeletal measurements, whereas non-extraction patient treatment showed a slight increase. The treatment time was also significantly higher in the extraction group.


Asunto(s)
Maloclusión Clase I de Angle/patología , Maloclusión Clase I de Angle/terapia , Extracción Dental , Dimensión Vertical , Adolescente , Diente Premolar , Cefalometría , Niño , Análisis Discriminante , Femenino , Humanos , Masculino , Maloclusión Clase I de Angle/diagnóstico por imagen , Radiografía Panorámica , Factores de Tiempo
16.
Am J Orthod Dentofacial Orthop ; 152(3): 371-381, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28863918

RESUMEN

INTRODUCTION: Patients with cleft lip and palate (CLP) suffer from several esthetic and functional challenges. Comprehensive treatment of these patients involves orthognathic surgery that may lead to velopharyngeal insufficiency or reduction in lower airway. Several cases of airway insufficiency, velopharyngeal incompetence, snoring, hypopnea, and obstructive sleep apnea have been reported in subjects with CLP. The aim of this study was to compare the anteroposterior dimensions of the oropharyngeal airway at 5 levels, the height of the oropharyngeal column, and the volume of the oropharyngeal airway in subjects with and without CLP. METHODS: The sample consisted of 62 patients with CLP and 42 subjects with Angle Class I malocclusion. Anteroposterior dimension, height, and volume of the oropharyngeal airway were measured using the midsagittal and axial slices obtained from 3-dimensional digital volume tomographic scans for both groups. RESULTS: The anteroposterior dimensions of the airway were significantly reduced in the study subjects compared with the control group at the level of the postnasal spine, the base of the tongue, and the epiglottis. The airway dimensions measured on the axial sections at the level of the palatal and epiglottic plane were also significantly lower in the study group. The height and volume of the oropharyngeal airway were also significantly smaller in patients with CLP compared with subjects without CLP. CONCLUSIONS: Patients with CLP showed reduced dimensions and volumes of the oropharyngeal airway in all 3 planes compared with the control group.


Asunto(s)
Labio Leporino/patología , Fisura del Paladar/patología , Orofaringe/patología , Adolescente , Estudios de Casos y Controles , Niño , Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Maloclusión Clase I de Angle/diagnóstico por imagen , Maloclusión Clase I de Angle/patología , Orofaringe/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
17.
Am J Orthod Dentofacial Orthop ; 152(2): 242-249, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28760286

RESUMEN

INTRODUCTION: The Frankfort horizontal (FH) is a plane that intersects both porions and the left orbitale. However, other combinations of points have also been used to define this plane in 3-dimensional cephalometry. These variations are based on the hypothesis that they do not affect the cephalometric analysis. We investigated the validity of this hypothesis. METHODS: The material included cone-beam computed tomography data sets of 82 adult subjects with Class I molar relationship. A third-party method of cone-beam computed tomography-based 3-dimensional cephalometry was performed using 7 setups of the FH plane. Six lateral cephalometric hard tissue measurements relative to the FH plane were carried out for each setup. Measurement differences were calculated for each pair of setups of the FH plane. The number of occurrences of differences greater than the limits of agreement was counted for each of the 6 measurements. RESULTS: Only 3 of 21 pairs of setups had no occurrences for the 6 measurements. No measurement had no occurrences for the 21 pairs of setups. Setups based on left or right porion and both orbitales had the greatest number of occurrences for the 6 measurements. CONCLUSIONS: This investigation showed that significant and undesirable measurement differences can be produced by varying the definition of the FH plane.


Asunto(s)
Cefalometría/métodos , Tomografía Computarizada de Haz Cónico/métodos , Imagenología Tridimensional/métodos , Adolescente , Adulto , Puntos Anatómicos de Referencia/diagnóstico por imagen , Puntos Anatómicos de Referencia/patología , Huesos Faciales/diagnóstico por imagen , Huesos Faciales/patología , Femenino , Humanos , Masculino , Maloclusión Clase I de Angle/diagnóstico por imagen , Maloclusión Clase I de Angle/patología , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Radiografía Dental/métodos , Cráneo/diagnóstico por imagen , Cráneo/patología , Adulto Joven
18.
Am J Orthod Dentofacial Orthop ; 151(5): 914-920, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28457269

RESUMEN

INTRODUCTION: Our objective was to evaluate the craniofacial growth of subjects with untreated Class II Division 2 malocclusion. METHODS: A mixed longitudinal sample of 39 white Class II Division 2 subjects was analyzed at 5 time points: T1 (6 or 7 years), T2 (9 or 10 years), T3 (12 or 13 years), T4 (15 or 16 years), and T5 (18 or 19 years). They were compared with an age- and sex- matched sample of Class I controls. Seventeen measurements (12 angular, 5 proportional) were computed. Multilevel modeling procedures were used to statistically describe the growth changes and to evaluate group differences. RESULTS: There were no group differences in the relative sizes and anteroposterior positions of the jaws during childhood, adolescence, or early adulthood. Subjects with Class II Division 2 malocclusion demonstrated significantly (P <0.05) smaller mandibular plane angles, smaller palatal-to-mandibular plane angles, larger posterior-to-anterior facial height ratios, smaller gonial angles, smaller cranial base angles, larger interincisal angles, and more retroclined maxillary incisors than did the Class I subjects. The hypodivergent patterns were established early and became more pronounced over time. Group differences in the mandibular plane angle, palatal-to-mandibular plane angle, gonial angle, interincisal angle, and maxillary incisor-to-cranial base angle, as well as the posterior-to-anterior facial height ratio all increased over time; the difference in the cranial base angle remained unchanged over time. Retroclination of the maxillary incisors occurred primarily during the early mixed dentition. CONCLUSIONS: Subjects with Class II Division 2 malocclusion are more hypodivergent and have more upright maxillary incisors than do subjects with Class I occlusion. Hypodivergence establishes itself early and increases progressively through early adulthood; maxillary incisor retroclination occurs early.


Asunto(s)
Maloclusión Clase II de Angle/patología , Adolescente , Estudios de Casos y Controles , Cefalometría , Niño , Huesos Faciales/crecimiento & desarrollo , Huesos Faciales/patología , Femenino , Humanos , Incisivo/patología , Estudios Longitudinales , Masculino , Maloclusión Clase I de Angle/patología , Mandíbula/crecimiento & desarrollo , Mandíbula/patología , Maxilar/crecimiento & desarrollo , Maxilar/patología , Cráneo/crecimiento & desarrollo , Cráneo/patología , Adulto Joven
19.
Am J Orthod Dentofacial Orthop ; 151(5): 921-928, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28457270

RESUMEN

INTRODUCTION: Buccolingual inclinations of the maxillary permanent molars and intermolar widths increase with growth for Class I subjects. Changes for untreated Class II subjects have not yet been assessed. The aim of this study was to test the hypothesis that changes in palatal inclination of the maxillary molars and intermolar width throughout growth vary between Class I and Class II molar occlusions. METHODS: Patients were selected from the Forsyth/Moorrees Twin Study. Dental models taken for 6 consecutive years of 55 untreated subjects (28 with Angle Class I and 27 with Angle Class II occlusion) were scanned. The images were superimposed on the palatal rugae, and the angle between a reference plane and the buccolingual inclination plane was used to calculate the buccolingual molar inclination at each time point. The distance between lingual groove points was used to calculate the intermolar width. RESULTS: All molars showed increasing palatal inclinations over the 6 years. The change for each time interval was statistically significant. Class I subjects demonstrated significantly greater palatal inclination at each time point. The molar inclination changed by means of 4.99° for Class I subjects and 6.25° for Class II subjects. Intermolar width increased continuously (P <0.001) and was significantly greater (P <0.05) for Class I patients. CONCLUSIONS: These results suggest that palatal inclination of the maxillary permanent first molars occurs continuously between ages 9 and 14 years, with Class II subjects showing greater changes. The intermolar width increases steadily during this time, with Class II subjects having a narrower intermolar width and less change over time.


Asunto(s)
Maloclusión Clase II de Angle/patología , Maloclusión Clase I de Angle/patología , Diente Molar/crecimiento & desarrollo , Adolescente , Niño , Preescolar , Arco Dental/patología , Modelos Dentales , Femenino , Humanos , Masculino , Maxilar/crecimiento & desarrollo , Maxilar/patología , Diente Molar/patología , Paladar (Hueso)/crecimiento & desarrollo , Paladar (Hueso)/patología , Estudios Retrospectivos
20.
Odontology ; 105(1): 84-90, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27011328

RESUMEN

This study aimed to investigate the relationship between the morphological characteristics of maxillary incisors and the anterior occlusion. The study materials comprised dental casts and lateral cephalograms of 26 modern Mongolian females with Angle Class I normal occlusion (mean age, 21 years 5 months). Computed tomography (CT) images of the dental casts were taken with an X-ray micro-CT system (SMX-100CT, Shimadzu, Kyoto Japan). The thickness of the marginal ridges and incisal edges, and the overjet and overbite, was measured on the three-dimensional images of the dental casts. On the lateral cephalogram, maxillary incisor to sella-nasion plane angle (U1 to SN angle), maxillary incisor to nasion-point A plane distance (U1 to NA distance), mandibular incisor to nasion-point B plane distance (L1 to NB distance), incisor mandibular plane angle, and interincisal angle were measured by tracing the left incisors of the maxilla and mandible. Spearman's single rank correlation coefficients were used to investigate any correlation between measurement items for each maxillary incisor. The thickness of the marginal ridges and incisal edges was positively correlated with the overbite. The thickness of the incisal edges was positively correlated with the irregularity index of the maxilla. There were significant negative correlations between overbite and U1 to SN angle, U1 to NA distance, and L1 to NB distance. Significant positive correlations were noted between the overbite and the overjet. In conclusion, there was no strong relationship between the morphological characteristics of maxillary incisors and the anterior occlusion.


Asunto(s)
Oclusión Dental , Incisivo/anatomía & histología , Incisivo/diagnóstico por imagen , Maloclusión Clase I de Angle/diagnóstico por imagen , Maloclusión Clase I de Angle/patología , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Cefalometría , Modelos Dentales , Femenino , Humanos , Mongolia , Microtomografía por Rayos X , Adulto Joven
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