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1.
BMC Oral Health ; 21(1): 71, 2021 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-33593343

RESUMEN

BACKGROUND: The purpose of this study was to investigate the differences in configuration and dimensions of the anterior loop of the inferior alveolar nerve (ALIAN) in patients with and without mandibular asymmetry. METHOD: Preoperative computed tomography images of patients who had undergone orthognathic surgery from January 2016 to December 2018 at a single institution were analyzed. Subjects were classified into two groups as "Asymmetry group" and "Symmetry group". The distance from the most anterior and most inferior points of the ALIAN (IANant and IANinf) to the vertical and horizontal reference planes were measured (dAnt and dInf). The distance from IANant and IANinf to the mental foramen were also calculated (dAnt_MF and dInf_MF). The length of the mandibular body and symphysis area were measured. All measurements were analyzed using 3D analysis software. RESULTS: There were 57 total eligible subjects. In the Asymmetry group, dAnt and dAnt_MF on the non-deviated side were significantly longer than the deviated side (p < 0.001). dInf_MF on the non-deviated side was also significantly longer than the deviated side (p = 0.001). Mandibular body length was significantly longer on the non-deviated side (p < 0.001). There was no significant difference in length in the symphysis area (p = 0.623). In the Symmetry group, there was no difference between the left and right sides for all variables. CONCLUSION: In asymmetric patients, there is a difference tendency in the ALIAN between the deviated and non-deviated sides. In patients with mandibular asymmetry, this should be considered during surgery in the anterior mandible.


Asunto(s)
Asimetría Facial , Imagenología Tridimensional , Tomografía Computarizada de Haz Cónico , Asimetría Facial/diagnóstico por imagen , Humanos , Mandíbula/diagnóstico por imagen , Nervio Mandibular/diagnóstico por imagen , Tomografía Computarizada por Rayos X
2.
Medicina (Kaunas) ; 57(8)2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34441044

RESUMEN

Background and objectives: Mood instability (MI) is a stable trait associated with psychiatric disorders, yet there is a lack of tools to measure MI. The purpose of this study was to develop and validate the Mood Instability Questionnaire-Trait (MIQ-T) to evaluate MI in mood disorder patients. Material and methods: Items were taken from various established questionnaires to create an initial list of MIQ-T questions. Data from 309 psychiatric patients (n = 309; 62 major depressive disorder, 58 bipolar I disorder, and 189 bipolar II disorder) were gathered from their medical records and were utilized in an exploratory factor analysis to clarify the underlying components of MI. Then, anonymous survey data from 288 individuals from the general population were included in the analysis as a comparison group. Associations between MIQ-T and other previously validated clinical instruments for mood disorders were examined to test external validity. Results: The exploratory factor analysis demonstrated that the five-factor structure (Lability, Upward Tendency, Downward Tendency, Childhood Instability, and Seasonality) of 59 items was the most appropriate with clear, cohesive features. MIQ-T exhibited high internal consistency (α = 0.96) and moderate to strong correlations with other previously validated clinical instruments, which were consistent with theoretical predictions, providing evidence of criterion validity. Short forms were also created to address the high internal consistency value, which can indicate redundancy, and to increase the approachability of the measure. We found that the patients with bipolar II disorder had higher MIQ-T scores than the patients with bipolar I disorder or major depressive disorder and the comparison group. Conclusion: Together, these findings validate the newly developed MIQ-T as an instrument of mood instability. MIQ-T can be a potential research tool for mood disorder.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo Mayor , Niño , Trastorno Depresivo Mayor/diagnóstico , Humanos , Trastornos del Humor/diagnóstico , Fenotipo , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
3.
J Oral Maxillofac Surg ; 78(4): 629.e1-629.e10, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31887295

RESUMEN

PURPOSE: The position changing pattern of the condyles after intraoral vertical ramus osteotomy (IVRO) on the deviated and non-deviated sides is not clearly known. This study was conducted to evaluate the changes in condylar position after IVRO in patients with facial asymmetry and to compare the deviated and non-deviated sides using computed tomography imaging. MATERIALS AND METHODS: This retrospective cohort study investigated patients with a diagnosis of mandibular prognathism with facial asymmetry who had undergone bilateral IVRO with Le Fort I osteotomy. Condylar positions were recorded on the non-deviated and deviated sides in the midaxial, midsagittal, and coronal planes at 3 time points using 3-dimensional analysis software: preoperatively (T1), at 6 months postoperatively (T2), and at 12 months postoperatively (T3). Linear and angular changes in condyle position were measured and analyzed between T1, T2, and T3. Reliability and comparative analyses were conducted. RESULTS: Thirty-two patients were involved in this study. At T2, the most superior point of the condyle moved to 1.15 ± 0.24 mm (inferiorly) and 0.88 ± 0.23 mm (anteriorly) on the deviated side (P = .0002 and P = .0005, respectively) and to 0.99 ± 0.25 mm (inferiorly) and 1.08 ± 0.34 mm (anteriorly) on the non-deviated side, showing significant differences (P < .0001 and P = .0007, respectively) compared with T1. The condyle position showed a tendency to recover to its original position by T3. However, there were no statistically significant differences between T2 and T3 (P > .05). Furthermore, there were no statistically significant differences between the deviated and non-deviated sides over the entire follow-up period (P > .05). CONCLUSIONS: The condyles did not completely recover to their preoperative positions until 12 months postoperatively. There was no significant difference between the deviated and non-deviated sides in mandibular prognathism with facial asymmetry.


Asunto(s)
Asimetría Facial , Prognatismo , Cefalometría , Humanos , Mandíbula , Cóndilo Mandibular , Osteotomía Sagital de Rama Mandibular , Reproducibilidad de los Resultados , Estudios Retrospectivos
4.
Clin Oral Implants Res ; 27(9): 1187-92, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26498561

RESUMEN

OBJECTIVES: The aim of this animal study was to examine the effects of thread size in the implant neck area on peri-implant tissues in terms of BIC and hard- and soft-tissue dimensions. MATERIALS AND METHODS: Six Beagle dogs received experimental implants in the mandible 3 month after the removal of premolars and first molars (P2, P3, P4, and M1). Two different types of implants were installed in each animal: Anyone microthread(®) as Group 1 and Anyone(®) as Group 2. Resonance frequency test, intraoral radiography, micro-CT, and histomorphometry were used to evaluate peri-implant tissue after implantation periods of 4 and 8 weeks. RESULTS: No remarkable complication was observed during the healing period in either group. Resonance frequency testing revealed no significant difference between groups. In radiographic evaluation, Group 2 showed more bone loss than Group 1. However, this difference was not statistically significant. In the micro-CT analysis, BIC and BIV values and soft-tissue height were not significant in both groups. Histological analysis revealed no significant difference in BIC ratio, bone density, or bone loss between groups. However, soft-tissue height was significantly greater in Group 2 than in Group 1 (P = 0.0004). CONCLUSION: No difference in peri-implant hard or soft tissues was observed according to thread size in the implant neck area.


Asunto(s)
Proceso Alveolar/cirugía , Implantación Dental Endoósea/efectos adversos , Implantes Dentales/efectos adversos , Encía/cirugía , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/patología , Animales , Tomografía Computarizada de Haz Cónico , Implantación Dental Endoósea/instrumentación , Implantación Dental Endoósea/métodos , Perros , Encía/diagnóstico por imagen , Encía/patología , Microtomografía por Rayos X
5.
J Prosthet Dent ; 112(3): 501-7, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24721506

RESUMEN

STATEMENT OF PROBLEM: A discrepancy between crown width and implant width may contribute to potential bending overload. PURPOSE: The purpose of this study was to evaluate the influence of the crown width-fixture width ratio on crestal bone loss around single dental implants placed in the first molar area. MATERIAL AND METHODS: Seventy-six participants (37 men and 39 women; age range, 25-83 years; mean age [standard deviation], 56.3 ±10.6 years) were selected from individuals who were treated with single tooth implants between May 2004 and December 2009 at the Department of Periodontology, Gangnam Severance Dental Hospital. The marginal bone-level change and gingival parameters (modified plaque index and modified sulcus bleeding index) of the periimplant soft tissue were assessed 1 year after functional loading. The perpendicular distances from the vertical axis of each fixture to the most distal aspect of the crown and most mesial aspect of the crown were measured in the periapical radiographic view. RESULTS: No statistically significant relationship was found between crown width-fixture width ratio and the 1-year bone-level change (Pearson correlation, P=.06; Spearman rank test, P=.14). No statistically significant differences in marginal bone-level change were found between axial and nonaxial loading implants (2 independent samples t test; P=.19). The bone-level change for the surface adjacent and distant to the cantilever was not statistically significant (paired t test; P=.10). CONCLUSION: From this study, it may be concluded that off-axial loading that results from a high crown width-fixture width ratio does not increase the risk for periimplant marginal bone loss after 1-year functional loading.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Proceso Alveolar/fisiopatología , Implantes Dentales de Diente Único , Adulto , Anciano , Anciano de 80 o más Años , Coronas , Arco Dental/fisiopatología , Índice de Placa Dental , Diseño de Prótesis Dental , Prótesis Dental de Soporte Implantado , Femenino , Estudios de Seguimiento , Encía/anatomía & histología , Humanos , Masculino , Persona de Mediana Edad , Diente Molar , Índice Periodontal , Radiografía de Mordida Lateral , Estrés Mecánico
6.
J Prosthet Dent ; 111(4): 286-92, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24331850

RESUMEN

STATEMENT OF PROBLEM: Controversy exists as to whether missing second molars should be replaced to restore masticatory ability. PURPOSE: The purpose of this study was to analyze the alteration in masticatory ability associated with the implant restoration of the second molar; the subjective effect of implant treatment on the participant was also assessed. MATERIAL AND METHODS: Twenty-one individuals (13 men and 8 women) participated. Masticatory ability was recorded before the cementation of implant-supported single crowns, immediately after cementation, and 1 month after cementation. The occlusal load (Pa), the load-bearing contact area (mm(2)), and the maximum occlusal force (N) were calculated. A subjective evaluation of masticatory ability was conducted before treatment and 1 month after treatment through the use of a questionnaire to evaluate chewing difficulties and global satisfaction with treatment. The Wilcoxon signed rank test was used to analyze the difference in scores. RESULTS: The load-bearing contact area, maximum occlusal force, and participant satisfaction were found to increase significantly 1 month after the cementation of implant-supported single crowns. The restoration of the second molar with an implant increased both objective masticatory ability and subjective satisfaction 1 month after cementation of the implant-supported single crowns. CONCLUSIONS: Patients presenting with a missing second molar may benefit from replacement with implant-supported crowns. Longer study periods and larger sample populations are needed to obtain more definitive results.


Asunto(s)
Implantes Dentales de Diente Único , Masticación/fisiología , Diente Molar , Adaptación Fisiológica/fisiología , Adulto , Anciano , Fuerza de la Mordida , Cementación/métodos , Coronas/psicología , Implantes Dentales de Diente Único/psicología , Prótesis Dental de Soporte Implantado/psicología , Ingestión de Alimentos/fisiología , Femenino , Estudios de Seguimiento , Humanos , Registro de la Relación Maxilomandibular/instrumentación , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Calidad de Vida , Pérdida de Diente/rehabilitación , Resultado del Tratamiento
7.
Clin Oral Implants Res ; 23(10): 1147-51, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22092875

RESUMEN

OBJECTIVES: To evaluate and compare the effect of the coronal thread size on the marginal bone loss around the fixtures, when both implants were provided with threads to the top of fixture. MATERIALS AND METHODS: Two groups of implants, one with a macro-thread to the top of the fixture (A) and the other with a micro-thread to the top of the fixture (B), were placed adjacent to each other in the partially edentulous areas of 20 patients. Bone loss around each implant was analyzed after 1 year of functional loading. The bone losses after loading were compared using Wilcoxon's signed-rank test. RESULTS: The mean marginal bone losses (A, 0.154 ± 0.144 mm; B, 0.125 ± 0.136 mm) were not statistically significant between the two groups (P = 0.669). CONCLUSIONS: There was no significant difference between implant with macro- and micro-neck thread in terms of marginal bone loss after 1 year of loading.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Diseño de Prótesis Dental , Adulto , Anciano , Pérdida de Hueso Alveolar , Prótesis Dental de Soporte Implantado , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Resultado del Tratamiento
8.
Artículo en Inglés | MEDLINE | ID: mdl-34360271

RESUMEN

Background: With advances in next-generation sequencing technologies, the bisulfite conversion of genomic DNA followed by sequencing has become the predominant technique for quantifying genome-wide DNA methylation at single-base resolution. A large number of computational approaches are available in literature for identifying differentially methylated regions in bisulfite sequencing data, and more are being developed continuously. Results: Here, we focused on a comprehensive evaluation of commonly used differential methylation analysis methods and describe the potential strengths and limitations of each method. We found that there are large differences among methods, and no single method consistently ranked first in all benchmarking. Moreover, smoothing seemed not to improve the performance greatly, and a small number of replicates created more difficulties in the computational analysis of BS-seq data than low sequencing depth. Conclusions: Data analysis and interpretation should be performed with great care, especially when the number of replicates or sequencing depth is limited.


Asunto(s)
Metilación de ADN , Sulfitos , Secuenciación de Nucleótidos de Alto Rendimiento , Análisis de Secuencia de ADN
9.
Artículo en Inglés | MEDLINE | ID: mdl-33672300

RESUMEN

Hematopoietic cancer is a malignant transformation in immune system cells. Hematopoietic cancer is characterized by the cells that are expressed, so it is usually difficult to distinguish its heterogeneities in the hematopoiesis process. Traditional approaches for cancer subtyping use statistical techniques. Furthermore, due to the overfitting problem of small samples, in case of a minor cancer, it does not have enough sample material for building a classification model. Therefore, we propose not only to build a classification model for five major subtypes using two kinds of losses, namely reconstruction loss and classification loss, but also to extract suitable features using a deep autoencoder. Furthermore, for considering the data imbalance problem, we apply an oversampling algorithm, the synthetic minority oversampling technique (SMOTE). For validation of our proposed autoencoder-based feature extraction approach for hematopoietic cancer subtype classification, we compared other traditional feature selection algorithms (principal component analysis, non-negative matrix factorization) and classification algorithms with the SMOTE oversampling approach. Additionally, we used the Shapley Additive exPlanations (SHAP) interpretation technique in our model to explain the important gene/protein for hematopoietic cancer subtype classification. Furthermore, we compared five widely used classification algorithms, including logistic regression, random forest, k-nearest neighbor, artificial neural network and support vector machine. The results of autoencoder-based feature extraction approaches showed good performance, and the best result was the SMOTE oversampling-applied support vector machine algorithm consider both focal loss and reconstruction loss as the loss function for autoencoder (AE) feature selection approach, which produced 97.01% accuracy, 92.60% recall, 99.52% specificity, 93.54% F1-measure, 97.87% G-mean and 95.46% index of balanced accuracy as subtype classification performance measures.


Asunto(s)
Aprendizaje Profundo , Trasplante de Células Madre Hematopoyéticas , Neoplasias , Algoritmos , Redes Neurales de la Computación , Máquina de Vectores de Soporte
10.
Clin Oral Implants Res ; 21(4): 439-44, 2010 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20443797

RESUMEN

OBJECTIVES: To evaluate and to compare the effect of the conical neck design on marginal bone loss around the fixtures, when both implants were provided with micro-threads to the top of the fixture. MATERIALS AND METHODS: Two types of implant, one with a straight shape (S) and the other with a conical neck design (C) provided with a retentive element to the top of the fixture, were placed adjacent to each other in the partially edentulous areas of 12 patients. Bone loss around each implant was analyzed after 1 year of functional loading. The bone losses after loading were compared using Wilcoxon's signed-rank test. RESULTS: The mean marginal bone losses (S, 0.05 + or - 0.09 mm; C, 0.07 + or - 0.14 mm) were not statistically significant between the two groups (P=0.578). CONCLUSIONS: There was no significant difference between conical and straight neck implants in terms of marginal bone loss after 1 year of loading.


Asunto(s)
Pérdida de Hueso Alveolar/prevención & control , Implantación Dental Endoósea , Implantes Dentales , Diseño de Prótesis Dental , Anciano , Prótesis Dental de Soporte Implantado , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estadísticas no Paramétricas
11.
Clin Oral Implants Res ; 20(12): 1320-5, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19709065

RESUMEN

OBJECTIVE: To compare the interproximal soft tissue dimensions adjacent to single implant restorations in the premolar-molar position with those adjacent to the contra-lateral natural teeth. MATERIAL AND METHODS: Twenty-five patients with a single-tooth implant in premolar-molar position and healthy contra-lateral teeth were enrolled in this retrospective cross-sectional study. The reason for the extraction was periodontitis. Radiographs were used to measure the shortest distance from the tip of the papilla to the crestal bone in single implants and contra-lateral teeth. A Wilcoxon's signed-ranks test was used to examine the differences between the interproximal soft tissue dimensions adjacent to the single-tooth implant restorations (IS-STI) from those of the contra-lateral natural teeth (IS-NT). RESULTS: We found no significant difference between the mesial IS-STI and the mesial IS-NT (3.28+/-0.83/3.31+/-0.62; P=0.861), or between the distal IS-STI and the distal IS-NT (3.09+/-0.72/3.3+/-0.63; P=0.263). CONCLUSIONS: The interproximal soft tissue height adjacent to single-implant-supported restorations in the premolar-molar position is similar to that adjacent to the contra-lateral natural teeth.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales de Diente Único , Encía/anatomía & histología , Adulto , Anciano , Diente Premolar/diagnóstico por imagen , Estudios Transversales , Femenino , Encía/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Diente Molar/diagnóstico por imagen , Periodontitis/cirugía , Radiografía Panorámica , Estudios Retrospectivos , Estadísticas no Paramétricas , Extracción Dental , Resultado del Tratamiento
12.
J Periodontol ; 80(9): 1541-7, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19722807

RESUMEN

BACKGROUND: The purpose of the present study was to investigate whether bone level on the tooth side was the single dominant factor on the dimension of an interproximal papilla around single-tooth restorations made on a microthread, conical seal, and platform-switched design implant. METHODS: Periapical radiographs were taken of 17 patients, each of whom was treated with a single implant. The bone levels on the tooth (Dt) and implant (Di) sides were recorded. The dimension of the papilla (Ph) was measured as the shortest distance from the top of the papilla to the crestal bone. The marginal bone levels of the implants were also measured. The Pearson correlation coefficient was used to correlate the variables, and a regression analysis was used to determine whether Di or Dt had a significant (P <0.05) influence on Ph. RESULTS: A positive correlation existed between Ph and Di (r = 0.413; P = 0.023) and between Ph and Dt (r = 0.830; P <0.0001). However, only Dt had a significant influence on Ph. CONCLUSION: Dt is the dominant factor that influences the interproximal soft tissue dimension between a natural tooth and a single implant with a microthread, conical seal, and platform-switched design.


Asunto(s)
Proceso Alveolar/patología , Implantes Dentales de Diente Único , Diseño de Prótesis Dental , Encía/patología , Diente/patología , Adulto , Anciano , Pérdida de Hueso Alveolar/etiología , Pilares Dentales , Implantación Dental Endoósea/métodos , Índice de Placa Dental , Femenino , Hemorragia Gingival/etiología , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Índice Periodontal , Radiografía de Mordida Lateral , Propiedades de Superficie , Adulto Joven
13.
J Periodontol ; 80(6): 933-9, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19485823

RESUMEN

BACKGROUND: The objective of this study was to evaluate the influence of early exposure of the cover screw on crestal bone loss around implants. METHODS: The study population consisted of 19 patients who were treated with dental implants placed using a two-stage surgical protocol and had early exposed and non-exposed implants (20 early exposed and 20 non-exposed implants). The crestal bone loss at exposed and non-exposed implants in each patient was evaluated with a periapical radiograph taken at the first surgery and at suprastructure insertion using a computerized image-analysis system. The bone loss was compared using the Wilcoxon signed-rank test. RESULTS: The mean crestal bone loss at exposed implants was 0.40 +/- 0.53 mm, and it was 0.18 +/- 0.26 mm at non-exposed implants. The Wilcoxon signed-rank test revealed a statistically significant difference in crestal bone loss between exposed and non-exposed implants in the same patient (P = 0.02). CONCLUSIONS: The early exposure of the cover screw that results in breakdown of the mucosal seal seems to accelerate early peri-implant crestal bone loss. Periodic follow-up after the first surgery may be critical for minimizing the influence of early exposure.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Implantación Dental Endoósea/instrumentación , Implantes Dentales , Encía/patología , Adulto , Anciano , Anciano de 80 o más Años , Pilares Dentales , Implantación Dental Endoósea/métodos , Femenino , Estudios de Seguimiento , Encía/cirugía , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Oseointegración/fisiología , Radiografía de Mordida Lateral , Dehiscencia de la Herida Operatoria/complicaciones , Alveolo Dental/cirugía , Cicatrización de Heridas
14.
PLoS One ; 14(12): e0225991, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31805166

RESUMEN

Coronary heart disease (CHD) is one of the leading causes of death worldwide; if suffering from CHD and being in its end-stage, the most advanced treatments are required, such as heart surgery and heart transplant. Moreover, it is not easy to diagnose CHD at the earlier stage; hospitals diagnose it based on various types of medical tests. Thus, by predicting high-risk people who are to suffer from CHD, it is significant to reduce the risks of developing CHD. In recent years, some research works have been done using data mining to predict the risk of developing diseases based on medical tests. In this study, we have proposed a reconstruction error (RE) based deep neural networks (DNNs); this approach uses a deep autoencoder (AE) model for estimating RE. Initially, a training dataset is divided into two groups by their RE divergence on the deep AE model that learned from the whole training dataset. Next, two DNN classifiers are trained on each group of datasets separately by combining a RE based new feature with other risk factors to predict the risk of developing CHD. For creating the new feature, we use deep AE model that trained on the only high-risk dataset. We have performed an experiment to prove how the components of our proposed method work together more efficiently. As a result of our experiment, the performance measurements include accuracy, precision, recall, F-measure, and AUC score reached 86.3371%, 91.3716%, 82.9024%, 86.9148%, and 86.6568%, respectively. These results show that the proposed AE-DNNs outperformed regular machine learning-based classifiers for CHD risk prediction.


Asunto(s)
Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/etiología , Aprendizaje Profundo , Redes Neurales de la Computación , Algoritmos , Humanos , Reproducibilidad de los Resultados , Medición de Riesgo , Factores de Riesgo
15.
Maxillofac Plast Reconstr Surg ; 41(1): 57, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31867294

RESUMEN

BACKGROUND: The relationship between the lateral deviation of chin and the upper and middle facial third asymmetry is still controversial. The purpose of this study is to evaluate the correlation of upper and middle facial third asymmetry with lateral deviation of chin using 3-dimensional computed tomography. The study was conducted on patients who underwent orthognathic surgery from January 2016 to August 2017. A total of 40 patients were included in this retrospective study. A spiral scanner was used to obtain the 3-dimensional computed tomography scans. The landmarks were assigned on the reconstructed 3-dimensional images, and their locations were verified on the axial, midsagittal, and coronal slices. The Pearson correlation analysis was performed to evaluate the correlation between chin deviation and difference between the measurements of distances in paired craniofacial structures. Statistical analysis was performed at a significance level of 5%. RESULTS: In mandible, the degree of chin deviation was correlated with the mandibular length and mandibular body length. Mandibular length and mandibular body length are shorter on the deviated-chin side compared to that on the non-deviated side (mandibular length, r = -0.897, p value < 0.001; mandibular body length, r = -0.318, p value = 0.045). In the upper and middle facial thirds, the degree of chin deviation was correlated with the vertical asymmetry of the glenoid fossa and zygonion. Glenoid fossa and zygonion are superior on the deviated-chin side than on the non-deviated side (glenoid fossa, r = 0.317, p value = 0.046; zygonion, r = 0.357, p value = 0.024). CONCLUSION: Lateral deviation of chin is correlated with upper and middle facial third asymmetry as well as lower facial third asymmetry. As a result, treatment planning in patients with chin deviation should involve a careful evaluation of the asymmetry of the upper and middle facial thirds to ensure complete patient satisfaction.

16.
J Korean Assoc Oral Maxillofac Surg ; 45(6): 309-315, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31966975

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the validity of the existing classification and difficulty index of impacted mandibular third molars in clinical situations and propose a more practical classification system. MATERIALS AND METHODS: This study included 204 impacted mandibular third molars in 154 patients; panoramic x-ray images were obtained before tooth extraction. Factors including age, sex, and pattern of impaction were investigated. All impacted third molars were classified and scored for spatial relationship (1-5 points), depth (1-4 points), and ramus relationship (1-3 points). All variables were measured twice by the same observer at a minimum interval of one month. Finally, the difficulty index was defined based on the total points scored as slightly difficult (3-4 points), moderately difficult (5-7 points), very difficult (8-10 points), and extremely difficult (11-12 points). RESULTS: The strength of agreement of the total points scored and difficulty index were 0.855 and 0.746, respectively. Most cases were classified as moderately difficult (73.0%). Although only 13 out of 204 cases (6.4%) were classified as extremely difficult, patients classified as extremely difficult were the oldest (P<0.05). CONCLUSION: For difficulty classification, the authors propose one more difficult category beyond the existing three-step difficulty index: the clinician should consider the patient's age in the difficulty index evaluation.

17.
Maxillofac Plast Reconstr Surg ; 41(1): 11, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30915317

RESUMEN

BACKGROUND: Botulinum toxin injection on the masticatory muscle induces the osteopenic condition on the ipsilateral condyle. Bisphosphonate suppresses bone resorption and is used to treat osteopenic or osteoporotic condition. This study aimed to evaluate the effect of bisphosphonate administration on prevention of condylar resorption and botulinum toxin A-induced disuse osteopenia in rats. RESULTS: The volume of the condyle and bone volume/tissue volume (BV/TV, %) showed a strong tendency towards statistical significance (p = 0.052 and 0.058). Trabecular thickness (Tb.Th, mm) and trabecular number (Tb.N, 1/mm) were significantly smaller in the Botox group than in the other groups (p < 0.05). The volume of the condyle and BV/TV in the bisphosphonate 100 and bisphosphonate 200 groups showed similar values when compared with the control group. CONCLUSION: Bisphosphonate administration after botulinum toxin A injection in the masticatory muscles appears to prevent condyle resorption and botulinum toxin-induced disuse osteopenia in rats.

18.
Angle Orthod ; 78(3): 427-32, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18416623

RESUMEN

OBJECTIVE: To quantify the changes in the nose after bimaxillary surgery to correct skeletal Class III malocclusion and to test the hypothesis that there is no change in the nasal width following bimaxillary surgical correction of skeletal Class III when a nasal cinch is properly used. MATERIALS AND METHODS: Sixty-five adult Korean skeletal Class III patients who had received maxillary advancement/impaction and mandibular set-back surgery in conjunction with an alar base cinch suture were evaluated. The anthropometric variables of the nasal region were measured directly on the soft-tissue surface before and 6 months after surgery. RESULTS: After surgery, the alar width and alar base width had increased significantly (P < .001), while the nasal tip projection decreased (P < .001). The nostril morphology also showed widening (P < .001). There was a trend for females with a narrow alar width presurgically to have a larger amount of nasal widening compared with those with a broader alar width (P < .05). CONCLUSION: There is a high probability of nasal and nostril widening after bimaxillary surgery for skeletal Class III malocclusion in Koreans despite the careful performance of alar cinch suture. Nevertheless, the authors believe that alar cinch suture was positive in limiting the nasal widening to the minimum and would consider routine application during bimaxillary surgery for skeletal Class III especially for female patients with a narrow nose who are susceptible to these changes.


Asunto(s)
Maloclusión de Angle Clase III/cirugía , Nariz/patología , Adulto , Cefalometría , Femenino , Estudios de Seguimiento , Humanos , Corea (Geográfico) , Masculino , Mandíbula/patología , Mandíbula/cirugía , Maxilar/patología , Maxilar/cirugía , Hueso Nasal/patología , Nariz/cirugía , Factores Sexuales , Técnicas de Sutura , Dimensión Vertical
19.
J Korean Assoc Oral Maxillofac Surg ; 44(3): 120-127, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29963493

RESUMEN

OBJECTIVES: The aim of this study was to reveal how collagenases (matrix metalloproteinase [MMP]-1, 8, 13) and tissue inhibitor of metalloproteinase 1 (TIMP-1) are expressed in immunohistochemistry of retrodiscal tissue in temporomandibular joint disorder patients. MATERIALS AND METHODS: This study was conducted on 39 patients who underwent discoplasty or discectomy. Immunohistochemical staining was undertaken and expression levels of MMP-1, 8, 13, and TIMP-1 were evaluated. The status of internal derangement of disc, osteoarthritis, and joint effusion were analyzed using magnetic resonance imaging (MRI). Disc status observed during operation was also categorized. RESULTS: The more severe disc derangement was observed on MRI, the more increased expression of MMPs and TIMP-1 appeared. Regarding MMP-13 expression, 86.7% of late-stage disc displacement patients showed grade II or III. Expression level of MMPs or TIMP was not statistically significant associated with joint effusion level. In perforation and/or adhesion groups, all patients showed grade II or III expression of MMP-13. Once perforation occurred, MMP-13 showed increased expression with statistical significance. CONCLUSION: MMP-1 and MMP-13 expression seem to be related to progression of osteoarthritis whereas MMP-8 does not seem to have a specific role with regard to temporomandibular joint disorders. TIMP-1 is considered to be partly related to internal derangement rather than osteoarthritis, but it is not significant.

20.
Maxillofac Plast Reconstr Surg ; 40(1): 30, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30430101

RESUMEN

BACKGROUND: The purpose of the present study was to investigate the differences in the position and shape of the anterior loop of the inferior alveolar nerve (ALIAN) in relation to the growth pattern of the mandibular functional subunit. METHODS: The study was conducted on 56 patients among those who had undergone orthognathic surgery at the Gangnam Severance Hospital between January 2010 and December 2015. Preoperative computerized tomography (CT) images were analyzed using the Simplant OMS software (ver.14.0 Materialise Medical, Leuven, Belgium). The anterior and inferior lengths of ALIAN (dAnt and dInf) and each length of the mandibular functional subunits were measured. The relationship between dAnt, dInf, and the growth pattern of the mandibular subunits was analyzed. RESULTS: The length of the anterior portion of ALIAN (dAnt) reached 3.34 ± 1.59 mm in prognathism and 1.00 ± 0.97 mm in retrognathism. The length of the inferior portion of ALIAN (dInf) reached 6.81 ± 1.33 mm in prognathism and 5.56 ± 1.34 mm in retrognathism. The analysis of Pearson's correlation coefficiency on all samples showed that the lengths of functional subunits were positively correlated with the loop depth. The length of the symphysis area in prognathic patients was positively correlated with the anterior loop depth (p = 0.005). CONCLUSIONS: Both the anterior and inferior length of ALIAN are longer in prognathic patients. Especially, it seems to be associated with the growth of the symphysis area.

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