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1.
Niger J Clin Pract ; 24(6): 789-794, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34121723

RESUMEN

Background: In dentistry, single-jaw surgery or double-jaw surgery is performed depending on the patient's need to correct severe skeletal malocclusions. The effect of these surgical methods used in treatment is to be investigated with quasi-least squares regression (QLS), which is a new data analysis method for correlated data obtained by extending generalized estimating equations (GEE). Aim: The aim of this study is to investigate whether jaw surgery methods (single jaw and double jaw) and time are effective on some outcome variables (C point menton distance, cervical plane angle, distance from point C to pogonion perpendicular, angle between cervical plane and facial plane) using QLS method. Methods: In application, 114 measurements were performed on the lateral cephalometric radiographs of 34 patients aged 18 years and older who received orthodontic treatment and underwent surgery in the period of 2000-2018. The effects of time and group variables on four dependent variables were investigated and evaluated using QLS and GEE methods. Results: Single-jaw surgery and double-jaw surgery as a group variable on all outcome variables were not significant. Among the working correlation structures used in QLS, the highest correlation value was obtained by "Markov" working correlation structure. Conclusion: Single-jaw surgery and double-jaw surgery were found to be statistically insignificant for outcome variables examined. QLS is superior to GEE in cases where repeated measurements are performed at unequal time intervals and there are missing observations.


Asunto(s)
Procedimientos Quirúrgicos Ortognáticos , Biometría , Cefalometría , Humanos , Análisis de los Mínimos Cuadrados , Mandíbula , Resultado del Tratamiento
2.
Head Face Med ; 17(1): 17, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-34039391

RESUMEN

INTRODUCTION: The purpose of this study was to systematically identify variants in NOTCH signaling pathway genes that correlate with mandibular prognathism (MP) in the general Chinese population. METHODS: Targeted sequencing of NOTCH signaling pathway genes was conducted in 199 MP individuals and 197 class I malocclusion control individuals. The associations of common and rare variants with MP, cephalometric parameters, and continuous cephalometric phenotypes were analyzed by principal component (PC) analysis. The associations between rare variants and MP were tested for each gene. RESULTS: Six SNPs, including rs415929, rs520688, and rs423023 in an exonic region of NOTCH4; rs1044006 in an exonic region of NOTCH3; rs1051415 in an exonic region of JAG1; and rs75236173 in the 3'-untranslated region (3'-UTR) of NUMB were associated with MP (P < 0.05). One common variant, rs1051415, in an exonic region of JAG1 was significantly related to PC1 (P  = 3.608 × 10- 4), which explained 24.3% of the overall phenotypic variation observed and corresponded to the sagittal mandibular position towards the maxilla, ranging from a posterior positioned mandible to an anterior positioned mandible. Additionally, 41 other variants were associated with PC1-5 (P  <  0.05). With respect to rare variant analysis, variants within the EP300, NCOR2, and PSEN2 gene showed an association with MP (t   < 0 .05). CONCLUSIONS: An association between NOTCH signaling pathway genes and MP has been identified.


Asunto(s)
Maloclusión de Angle Clase III , Prognatismo , Cefalometría , Humanos , Mandíbula , Prognatismo/genética , Transducción de Señal/genética
3.
Dental Press J Orthod ; 26(2): e21bbo2, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34008742

RESUMEN

The Herbst appliance can be very effective in treatment of Class II patients with mandibular retrognathism. Because of the continuous action in a full-time basis, treatment time using it normally takes from six to ten months, and is usually followed by a second phase of full fixed appliances, in order to obtain both occlusal refinement and long term stability. Despite Herbst appliance's effectiveness in the occlusal and dentoalveolar perspectives, its facial results may differ among patients with different growth patterns, as well as in distinct stages of skeletal maturation. In the current paper, two patients with different facial patterns are presented, who were treated under the same protocol, using Herbst and full fixed appliances in different skeletal maturation stages, and both dentoalveolar and facial results are compared and discussed.


Asunto(s)
Maloclusión Clase II de Angle , Avance Mandibular , Aparatos Ortodóncicos Funcionales , Cefalometría , Cara/anatomía & histología , Cara/diagnóstico por imagen , Humanos , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/terapia
4.
J Craniomaxillofac Surg ; 49(6): 435-442, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33934974

RESUMEN

We aimed to compare the reliability of the surgery-first approach and the traditional orthodontic-first approach for the correction of facial asymmetry based on the new classification of facial asymmetry. Patients with facial asymmetry who underwent orthognathic surgery between January 2016 and January 2019 were included. Cephalometric changes and relapse ratios were analyzed 12 months before and after surgery. Patients were divided into horizontal and vertical asymmetry groups based on the asymmetry vector, and subgroup analysis was conducted. The surgery-first approach without presurgical orthodontic treatment and the orthodontic-first approach showed a similar degree of asymmetry correction and skeletal stability. The relapse ratios of the maxilla height in the surgery-first and orthodontic-first groups were 0.25 ± 0.21 and 0.27 ± 0.25, respectively (p = 0.63), the relapse ratios of the maxilla width were 0.31 ± 0.32 and 0.21 ± 0.2, respectively (p = 0.14), the mandibular height relapse ratios were 0.34 ± 0.58 and 0.29 ± 0.36, respectively (p = 0.69), and the mandibular width relapse ratios were 0.12 ± 0.22 and 0.26 ± 0.31, respectively (p = 0.058). The treatment period of the surgery-first group (18.5 ± 5.3 months) was significantly shorter than that of the orthodontic-first group (22.9 ± 7.5 months, p = 0.024). Among the surgery-first group, patients with vertical asymmetry (15.0 ± 3.2 months) had a shorter treatment than those with horizontal asymmetry (21.6 ± 6.8 months, p = 0.006). Although contesting traditional standards is always challenging, the surgery-first orthognathic approach may lead to a new era in traditional orthognathic approaches. This new classification of facial asymmetry could be useful and practical when treating patients with facial asymmetry regardless of the etiology.


Asunto(s)
Maloclusión de Angle Clase III , Procedimientos Quirúrgicos Ortognáticos , Cefalometría , Asimetría Facial/diagnóstico por imagen , Asimetría Facial/cirugía , Humanos , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Reproducibilidad de los Resultados , Resultado del Tratamiento
5.
Dental Press J Orthod ; 26(2): e2119378, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33950082

RESUMEN

OBJECTIVE: To determine whether separating the alignment and leveling phases can reduce proclination of the mandibular incisors. METHODS: Eligibility criteria included Class I subjects with an irregularity index of 3-5 mm, 3-4 mm curve-of-Spee (COS), and non-extraction treatment. Thirty adults were randomly allocated into two groups: (1) Control group was leveled and aligned simultaneously with flat archwires progressively to 0.016x0.022-in stainless-steel; (2) Experimental group was aligned first with 0.014-in-superelastic NiTi with mild accentuated COS, then leveled using 0.016x0.022-in beta-titanium accentuated COS archwires and gradually reduced the curve until flat. Mandibular incisor position and inclination were evaluated by cephalometric analysis. COS and irregularity index were evaluated in study models. Assessment was conducted twice after 0.016-in NiTi and after 0.016x0.022-in stainless-steel archwire placements. Dental changes from cephalograms and models were compared within group using paired t-test and between groups using independent t-test. RESULTS: Control group: Round-wire-phase, mandibular incisors tipped labially (4.38° and 1 mm) with intrusion (-1.13 mm); Rectangular-wire-phase, mandibular incisors further intruded and proclined (-0.63 mm and 1.38°). Experimental group: During aligning with round accentuated COS archwires, mandibular incisors tipped very slightly labially (0.75° and 0.50 mm) with no significant intrusion; during leveling with rectangular archwires, incisors majorly intruded (1.75 mm) with slight proclination (1.81°). The experimental group had significant less incisor proclination (control: 5.76°, experimental: 2.56°) with more incisor intrusion (control: -1.75 mm, experimental: -2.13 mm). The COS in experimental group showed significant greater reduction (-2.88 mm) than that of the control group (-1.69 mm). CONCLUSION: In control group, mandibular incisor proclination was markedly observed in round archwires, with further proclination caused by rectangular archwires. In experimental group, minimal proclination was exhibited when accentuated COS round archwires were used for aligning. Leveling with rectangular archwires caused less proclination with more COS reduction.


Asunto(s)
Incisivo , Técnicas de Movimiento Dental , Cefalometría , Mandíbula , Alambres para Ortodoncia , Acero Inoxidable
6.
Prog Orthod ; 22(1): 12, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33937947

RESUMEN

BACKGROUND: The purpose of this study was to compare the stress distribution and displacement patterns of the one versus two maxillary molars distalization with iPanda and to evaluate the biomechanical effect of distalization on the iPanda using the finite element method. METHODS: The finite element models of a maxillary arch with complete dentition, periodontal ligament, palatal and alveolar bone, and an iPanda connected to a pair of midpalatal miniscrews were created. Two models were created to simulate maxillary molar distalization. In the first model, the iPanda was connected to the second molar to simulate a single molar distalization. In the second model, the iPanda was connected to the first molar to simulate "en-masse" first and second molar distalization. A varying force from 50 to 200 g was applied. The stress distribution and displacement patterns were analyzed. RESULTS: For one molar, the stress was concentrated at the furcation and along the distal surface in all roots with a large amount of distalization and distobuccal crown tipping. For two molars, the stress in the first molar was 10 times higher than in the second molar with a great tendency for buccal tipping and a minimal amount of distalization. Moreover, the stress concentration on the distal miniscrew was six times higher than in the mesial miniscrew with an extrusive and intrusive vector, respectively. CONCLUSIONS: Individual molar distalization provides the most effective stress distribution and displacement patterns with reduced force levels. In contrast, the en-masse distalization of two molars results in increased force levels with undesirable effects in the transverse and vertical direction.


Asunto(s)
Maloclusión Clase II de Angle , Diseño de Aparato Ortodóncico , Cefalometría , Análisis de Elementos Finitos , Humanos , Maxilar , Diente Molar , Técnicas de Movimiento Dental
7.
Am J Orthod Dentofacial Orthop ; 159(5): 627-634, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33931222

RESUMEN

INTRODUCTION: This study aimed to evaluate and compare the bridging and dimensions of the sella turcica and calcification of the ponticulus posticus in subjects with different dental anomalies. METHODS: Pretreatment records of orthodontic patients with palatally impacted canines (n = 95), mandibular second premolar agenesis (n = 45), maxillary lateral incisor agenesis (n = 75), tooth transpositions (TT, n = 25), peg-shaped maxillary lateral incisors (n = 30), and third molar agenesis (TMA, n = 145) were analyzed and compared with the control group (CG) consisting of 145 subjects with skeletal Class I malocclusion and no dental anomalies. The length, diameter, and depth of the sella turcica were calculated for each patient. The degree of sella turcica bridging was scored as type I, II, and III, whereas the extent of ponticulus posticus was classified as Class I, II, and III. RESULTS: Only decreases in the length and diameter of the sella turcica in subjects with TT were found to be statistically significant. Although type II bridging frequency was found to be significantly lower in subjects with mandibular second premolar agenesis, maxillary lateral incisor agenesis, TT, and TMA, type III bridging frequency was found to be significantly higher only in subjects with TMA. The decrease in Class I calcification frequencies and the increase in Class II calcification frequencies were found to be significant in subjects with palatally impacted canines, TT, and TMA compared with the CG. In addition, the presence of Class III calcification was found to be significantly more frequent in subjects with TMA than in the CG. CONCLUSIONS: Although type II and type III bridging frequencies were found to be higher than in previous studies because of the higher type II bridging frequency in the CG, type II bridging frequency was found to be insignificant. Furthermore, an increased frequency of ponticulus posticus calcification was observed in subjects with palatally impacted canines, TT, and TMA.


Asunto(s)
Atlas Cervical , Diente Impactado , Diente Premolar , Cefalometría , Humanos , Silla Turca/diagnóstico por imagen , Diente Impactado/diagnóstico por imagen
8.
J Clin Pediatr Dent ; 45(2): 140-145, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33951166

RESUMEN

AIM: To compare maxillary development of individuals with unilateral cleft lip and palate (CLP) to individuals with skeletal Class I and Class III malocclusions. STUDY DESIGN: Cephalometric X-ray films from 90 patients (mean age: 13 ± 2.3 years) were used. The number of samples was determined by Power analysis and three groups consisting of 30 patients (Group 1: Skeletal Class I, Group 2: Skeletal Class III, Group 3: CLP) were formed. A total of 13 cephalometric measurements were performed using Dolphin imaging software 11.7. The Kruskal-Wallis and ANOVA tests were used to calculate the differences. The Dunn test and Bonferroni correction were used in paired group comparisons. RESULTS: SNA, Co-A, A-PTV Horizontal, Na-APog, A-Na-Pog, FH-NA, Sn'-Mx1, MxOP-TVL (p<0.001***), U6-PTV Vertical (p<0.01**), and NaBa PTV-Gn (p<0.05*) values were significantly different between the three groups. There was no significant difference in Na-ANS, FH-NPog, or Mx1 labial-ULA. SNA, Co-A, A-PTV Horizontal, Na-APog, and A-Na-Pog values between the 1st and 2nd groups and between the 1st and 3rd groups (p<0.001***) were significantly different. FH-Na-A, Sn'-Mx1, MxOP-TVL (p<0.001***), and U6-PTV vertical were different between groups 1 and 3 (p<0.01**), while FH-Na-A (p<0.001***), Sn'-Mx1, MxOP-TVL (p<0.01**), A-PTV Horizontal, and A-Na-Pog (p<0.05*) were significantly different between groups 2 and 3. CONCLUSION: Maxillary development in CLP differs from skeletal Class I but is similar to skeletal Class III. Considering the delay in maxillary development in the CLP patient, maxillary protraction and maxillary expansion are important treatment protocols in the early period.


Asunto(s)
Labio Leporino , Fisura del Paladar , Maloclusión de Angle Clase III , Cefalometría , Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Humanos , Maloclusión de Angle Clase III/diagnóstico por imagen , Maxilar/diagnóstico por imagen
9.
Head Face Med ; 17(1): 15, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33952290

RESUMEN

OBJECTIVE: The aim of this study was to analyze the use of modified, cast splint Herbst appliances for the treatment of skeletal class II as an alternative to surgical bite correction over a period of five years. MATERIALS AND METHODS: The patient cases all originate from the patients of the Department of Orthodontics at the University Medical Center of the Johannes Gutenberg University Mainz, Germany and the orthodontic practice Dres. Zöller, Kaiserslautern, Germany. Inclusion criteria were orthodontic treatment with the Herbst appliance and its modifications. The type of modification, number and frequency of the different modifications were determined on the basis of patient files, X-ray documents, photos and models. RESULTS: Of a total of 2881 new admissions over a period of five years, 1751 patients came from the Department of Orthodontics at the University Medical Center of the Johannes Gutenberg University Mainz and 1130 from the orthodontic practice in Kaiserslautern. A total of 336 patients were treated with a Herbst appliance during the period mentioned. 14 (13%) of the cases from the Herbst patient collective of the University Medical Center and 45 (19%) of the cases from the orthodontic practice were classified as modifications. The following modifications could be determined in descending order: University Medical Center Mainz: Herbst for anchorage during space closure (65%) > distalization (14%) ≥ bar construction as a space maintainer (14%) > Herbst applicance for anchoring for the adjustment of impacted teeth (7%); orthodontic practice Kaiserslautern: Herbst appliance with quadhelix in the maxilla (42%) > distalization (27%) > space closure (15%) > bar construction as a space maintainer (9%) > adjustment of impacted teeth (7%), multiple modifications occurred at 11%. The combination of quadhelix and Herbst appliance as well as multiple modifications have not yet been used in the University Medical Center Mainz. As an alternative to dysgnathia surgery, 23 adult patients (> 18 years) from the University Medical Center and 22 from the orthodontic practice were treated with a Herbst appliance. CONCLUSION: Nearly 12% of Herbst appliances are used in everyday orthodontic practice and almost 18% of these are used with modification(s). The high anchoring quality and force-effect geometry of the Herbst appliance is suitable for combining and treating various other treatment tasks in addition to the classical treatment task of class II therapy.


Asunto(s)
Maloclusión Clase II de Angle , Aparatos Ortodóncicos Funcionales , Cefalometría , Alemania/epidemiología , Humanos , Individualidad , Prevalencia
10.
J Clin Pediatr Dent ; 45(2): 117-122, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33951171

RESUMEN

OBJECTIVE: To identify the association of occlusal disorders in patients with sickle cell disease (SCD). STUDY DESIGN: A literature review was conducted, and articles published between 2010 and 2019 were searched on Bireme and PubMed websites and in MEDLINE and LILACS databases, in English, Portuguese, and Spanish, using the keywords "malocclusion," "sickle cell disease," and "cephalometry," combined by Boolean operators AND and OR. One of the criteria for the selection of articles was the presence of adolescents in the sample. This methodology followed the PRISMA recommendations. Seventy-nine articles were found, seven of which were included in the review as they met the inclusion criteria and the study goals. RESULTS: The prevalence of malocclusion in SCD patients ranged from 62.9% to 100%, which was considered very severe in 30.1% to 80.6%. The most common occlusal changes were Angle's class II malocclusion, increased maxillary overjet, and anterior open bite. In addition, class II skeletal pattern was the most prevalent due to mandibular retrusion. CONCLUSION: Malocclusion prevalence in SCD patients is high and considered to be a risk factor, with a significant rate of very severe malocclusion when compared to healthy patients.


Asunto(s)
Anemia de Células Falciformes , Maloclusión Clase II de Angle , Maloclusión , Mordida Abierta , Sobremordida , Adolescente , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/epidemiología , Cefalometría , Humanos , Maloclusión/epidemiología
11.
Niger J Clin Pract ; 24(5): 692-704, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34018979

RESUMEN

Objectives: This cross-sectional observational retrospective study aimed at assessing the cephalometric skeleto-dental features of class I, II, and III skeletal relationships of Saudi female school children samples and comparing the results to the established North American Caucasian cephalometric standards. Methods: The sample consisted of 205 retrospective lateral cephalometric radiographs of female school children. The age range of the subjects was between 10 and 13 years with a mean age of 11 ± 1 years. Several cephalometric and constructed points were identified. Angular, linear, and proportional measurements were obtained and analyzed. The skeleto-dental features of class II and class III were compared to class I of this sample then compared with the established North American Caucasian population. Different angular, linear, and proportional variables were investigated. Descriptive statistics and student t-test were used for data analysis. Results: The distribution of the skeletal relationship revealed that 68.3% of the sample showed class I relationship, 16.1% class II, and 15.6% class III. The result indicates significant differences between the different classes. A greater tendency towards class II facial pattern and more convex profile among Saudis were detected in the present study compared to Caucasians. Furthermore, The dentoalveolar relationship results showed more Bi-maxillary protrusion among Saudi females compared to the North American Caucasians. Conclusion: The results obtained can be of great value in distinguishing the various skeleto-dental features in the different skeletal classes among the Saudi females and in the clinical diagnosis and treatment planning. Furthermore, the results of the study can also serve as a base-line for future investigations in Saudi Arabia.


Asunto(s)
Cara , Adolescente , Cefalometría , Niño , Estudios Transversales , Cara/anatomía & histología , Femenino , Humanos , Estudios Retrospectivos , Arabia Saudita , Estados Unidos
12.
J Pak Med Assoc ; 71(3): 863-867, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34057937

RESUMEN

OBJECTIVE: To evaluate the parallelism of natural maxillary occlusal plane with inter-pupillary line and ala-tragus line, and to evaluate the anatomic relationship of natural mandibular occlusal plane with retromolar pad among dentate subjects. METHODS: The cross-sectional study was conducted from September 2017 to February 2018 at Fatima Jinnah Dental College, Karachi, and comprised front and profile photographs of subjects aged 20-28 years while holding the camper's plane against the maxillary occlusal plane. The photographs were imported in a software and an interpupillary line was drawn and the angle with Camper's plane was measured. On both profile pictures, lines were drawn from base of the ala to the superior, middle and inferior points on the tragus. The angle between ala-tragus line and Camper's plane were measured. Intra-orally, height of the mandibular occlusal plane in relation to the retromolar pad was evaluated using a stainless steel scale. Data was analysed using SPSS 23. RESULTS: Of the 109 subjects with a mean age of 23.03±1.36 years, 76(69.72%) were females. Horizontal parallelism of occlusal plane with inter-pupillary line was observed with a mean angle of 1.17±1.27 degrees. The angle between the occlusal plane and the inferior ala-tragus line was 4.25 degrees on the right side, and 4.50 degrees on the left. Intraorally, mandibular occlusal plane coincided with the inferior 48(44%) and the middle third 48(44%) of the retromolar pad. CONCLUSIONS: Inter-pupillary line and retromolar pad area should be used as a guide in the determination of plane of occlusion. The ala-tragus line was not found to be a reliable guide.


Asunto(s)
Oclusión Dental , Boca , Adulto , Cefalometría , Estudios Transversales , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Adulto Joven
13.
Prog Orthod ; 22(1): 14, 2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34056670

RESUMEN

OBJECTIVE: The rapid development of artificial intelligence technologies for medical imaging has recently enabled automatic identification of anatomical landmarks on radiographs. The purpose of this study was to compare the results of an automatic cephalometric analysis using convolutional neural network with those obtained by a conventional cephalometric approach. MATERIAL AND METHODS: Cephalometric measurements of lateral cephalograms from 35 patients were obtained using an automatic program and a conventional program. Fifteen skeletal cephalometric measurements, nine dental cephalometric measurements, and two soft tissue cephalometric measurements obtained by the two methods were compared using paired t test and Bland-Altman plots. RESULTS: A comparison between the measurements from the automatic and conventional cephalometric analyses in terms of the paired t test confirmed that the saddle angle, linear measurements of maxillary incisor to NA line, and mandibular incisor to NB line showed statistically significant differences. All measurements were within the limits of agreement based on the Bland-Altman plots. The widths of limits of agreement were wider in dental measurements than those in the skeletal measurements. CONCLUSIONS: Automatic cephalometric analyses based on convolutional neural network may offer clinically acceptable diagnostic performance. Careful consideration and additional manual adjustment are needed for dental measurements regarding tooth structures for higher accuracy and better performance.


Asunto(s)
Inteligencia Artificial , Mandíbula , Cefalometría , Humanos , Mandíbula/diagnóstico por imagen , Redes Neurales de la Computación , Reproducibilidad de los Resultados
17.
Arch Oral Biol ; 127: 105157, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34015688

RESUMEN

OBJECTIVE: To use cone beam computed tomography (CBCT) scans to analyze mandibular symmetry, the occlusal plane and their correlations in patients with high-angle skeletal class III malocclusion and jaw deformity. DESIGN: Reconstructed images simulated of CBCT data of 20 adult patients with high-angle skeletal class III malocclusion and jaw asymmetry (Experimental group) and 20 adult patients of skeletal class I with normal faces (Control group) were measured with a three-dimensional (3D) geometric morphological measurement system. Related landmarks, lines and planes were marked and relevant distances and angles of 3D craniofacial structures were measured. The Student t-test was performed to assess symmetry. With the help of the Pearson correlation and Linear regression, we explored the correlations and other relationships among them. RESULTS: Compared with control group, the symmetrical differences in experimental group were concentrated in condyle, coracoid process, mandibular angle, mandibular first molar area and the chin (P < 0.05). A strong positive correlation was found between the degree of mandibular deviation and the inclination of the occlusal plane in the coronal position (r = 0.860, P < 0.001) and a linear relationship between them was found: Y = 1.300 + 0.419X (the inclination of occlusal plane was Y, and the mandibular deviation was X). CONCLUSIONS: Certain characteristics of mandibular symmetry and the occlusal plane were found in patients with high-angle skeletal class III malocclusion and jaw asymmetry. These findings provide references for doctors to pay attention to the degree and location of mandibular asymmetry and to determine the occlusal plane.


Asunto(s)
Oclusión Dental , Maloclusión , Adulto , Cefalometría , Tomografía Computarizada de Haz Cónico , Humanos , Imagenología Tridimensional , Mandíbula/diagnóstico por imagen
18.
BMC Oral Health ; 21(1): 238, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33952217

RESUMEN

BACKGROUND: This study is aimed to (1) investigate the influence of sagittal and vertical patterns on mandibular cross-sectional morphology and to (2) provide visualized mandibular cross-sectional morphology in different groups with General Procrustes Analysis (GPA), canonical variance analysis (CVA) and discriminant function analysis (DFA). METHODS: 324 cone-beam computed tomography (CBCT) images were collected to analyze mandibular cross-sectional morphology and were categorized into 12 groups according to sagittal and vertical pattern and gender. One-way analysis of variance (ANOVA) was used to compare the difference among the groups. Thirty equidistant points were marked along the contour of mandibular cross-section and GPA, CVA and DFA were applied. RESULTS: (1) Mandibular height in hyperdivergent groups was significantly higher than that in normodivergent and hypodivergent groups (P < 0.05). (2) Hypodivergent groups showed significantly wider upper third of mandibular width from symphysis to molar region than that in hyperdivergent group (P < 0.05), except for the premolar and molar regions in male groups (P > 0.05). (3) Class II hyperdivergent group showed narrowest lower third width in the molar region, with the mean value of 12.03 mm in females and 11.98 mm in males. (4) For males and females, the ratio between height and lower third width at symphysis was significantly higher in Class II hyperdivergent group than that in Class I hyperdivergent group (P < 0.05). CONCLUSIONS: (1) The influence of vertical facial patterns on mandibular cross-sectional morphology is more obvious than that of sagittal skeletal pattern. (2) Subjects with increased vertical dimension presented with a remarkable "slimer" mandibular cross-sectional morphology at symphysis. (3) A deeper curve along the anterior contour of symphysis in Class II hyperdivergent group was noted with GPA.


Asunto(s)
Tomografía Computarizada de Haz Cónico Espiral , Cefalometría , Tomografía Computarizada de Haz Cónico , Estudios Transversales , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen
19.
Head Face Med ; 17(1): 13, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33853633

RESUMEN

BACKGROUND: Orthognathic surgery can be carried out using isolated mandibular or maxillary movement and bimaxillary procedures. In cases of moderate skeletal malocclusion, camouflage treatment by premolar extraction is another treatment option. All these surgical procedures can have a different impact on the soft tissue profile. METHODS: The changes in the soft tissue profile of 187 patients (Class II: 53, Class III: 134) were investigated. The treatment approaches were differentiated as follows: Class II: mandible advancement (MnA), bimaxillary surgery (MxS/MnA), upper extraction (UpEX), or Class III: maxillary advancement (MxA), mandible setback (MnS), bimaxillary surgery (MxA/MnS), and lower extraction (LowEX) as well as the extent of skeletal deviation (moderate Wits appraisal: - 7 mm to 7 mm, pronounced: Wits <- 7 mm, > 7 mm, respectively). This resulted in five groups for Class II treatment and seven groups for Class III treatment. RESULTS: In the Class II patients, a statistically significant difference (p ≤ 0.05) between UpEX and moderate MnA was found for facial profile (N'-Prn-Pog'), soft tissue profile (N'-Sn-Pog'), and mentolabial angle (Pog'-B'-Li). In the Class III patients, a statistically significant differences (p ≤ 0.05) occurred between LowEX and moderate MxA for facial profile (N'-Prn-Pog'), soft tissue profile (N'-Sn-Pog'), upper and lower lip distacne to esthetic line (Ls/Li-E-line), and lower lip length (Sto-Gn'). Only isolated significant differences (p < 0.05) were recognized between the moderate surgical Class II and III treatments as well between the pronounced Class III surgeries. No statistical differences were noticed between moderate and pronounced orthognathic surgery. CONCLUSIONS: When surgery is required, the influence of orthognathic surgical techniques on the profile seems to be less significant. However, it must be carefully considered if orthognathic or camouflage treatment should be done in moderate malocclusions as a moderate mandibular advancement in Class II therapy will straighten the soft tissue profile much more by increasing the facial and soft tissue profile angle and reducing the mentolabial angle than camouflage treatment. In contrast, moderate maxillary advancement in Class III therapy led to a significantly more convex facial and soft tissue profile by decreasing distances of the lips to the E-Line as well as the lower lip length.


Asunto(s)
Maloclusión de Angle Clase III , Procedimientos Quirúrgicos Ortognáticos , Cefalometría , Estética Dental , Humanos , Maloclusión de Angle Clase III/diagnóstico por imagen , Maloclusión de Angle Clase III/cirugía , Mandíbula , Resultado del Tratamiento
20.
Artículo en Inglés | MEDLINE | ID: mdl-33809695

RESUMEN

Nose shape, size, and inclination influence facial appearance, but few studies concern the relationship between the nasal profile and craniofacial structures. The objective of this study was to analyze association of nasal cephalometric variables with skeletal structures, age, and sex. Cephalometric and nasal analysis was performed in 386 Polish orthodontic patients (aged 9-25 years). Student t-test and Mann-Whitney test were used to compare quantitative variables and Pearson's or Spearman's correlation coefficients-to find correlations. Soft tissue facial convexity angle correlates to Holdaway ratio, ANB (A-Nasion-B), and Wits appraisal. Nasal dorsum axis, nose length, nose depth (1) and nose depth (2), nose hump, lower dorsum convexity, and columella convexity increase with age. Nasal base angle, nasolabial angle, nasomental angle, soft tissue facial convexity and nasal bone angle decrease with age. Nasal base angle and nasomental angle are smaller in females. Thus, a relationship exists between nasal morphology and sagittal jaw configuration. Nasal parameters significantly change with age. Sexual dimorphism characterizes nasal bone angle and nasomental angle.


Asunto(s)
Cara , Nariz , Adolescente , Adulto , Cefalometría , Niño , Cara/anatomía & histología , Cara/diagnóstico por imagen , Femenino , Humanos , Nariz/anatomía & histología , Nariz/diagnóstico por imagen , Radiografía , Caracteres Sexuales , Adulto Joven
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