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1.
Am J Orthod Dentofacial Orthop ; 158(6): 834-839, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33097363

RESUMO

INTRODUCTION: Orthodontic miniscrews have become popular not only because they can provide an absolute form of anchorage, but also because they can reduce the required patient compliance when compared with traditional orthodontic anchorage. The objective of this study was to examine success rates of miniscrews placed by orthodontic residents and to evaluate which factors may affect insertion outcomes. METHODS: The sample consisted of 109 consecutive miniscrews placed in 60 patients (27 males and 33 females). Miniscrews were placed at 4 different insertion sites (anterior palate [n = 31], palatal alveolar process [n = 25], maxillary buccal alveolar process [n = 15], and mandibular buccal alveolar process [n = 38]). Analysis of variance tests were used to evaluate the influence of insertion sites and anchorage type (direct vs indirect) on the success rate. RESULTS: The overall success rate for miniscrews was 72.5%. The success rate was 83.9% in the anterior palate, 76% in the palatal alveolar process, 60% in the maxillary buccal alveolar process, and 65.8% in the mandibular buccal alveolar process. The success rate was significantly higher in indirect anchorage (84.2%) compared with direct anchorage (58.8%). CONCLUSIONS: Palatal miniscrews were more successful than buccal miniscrews. Indirect anchorage mechanics had a higher success rate than direct anchorage mechanics.


Assuntos
Internato e Residência , Procedimentos de Ancoragem Ortodôntica , Parafusos Ósseos , Feminino , Humanos , Masculino , Mandíbula , Desenho de Aparelho Ortodôntico
2.
J Craniofac Surg ; 31(4): 1098-1100, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32487834

RESUMO

BACKGROUND: Orthodontists and surgeons have been looking for more accurate methods to predict surgical outcomes in patients with skeletal discrepancies. METHODS: The sample consisted of 20 patients from the surgical clinic of a graduate orthodontic program who had been treated with Le Fort I maxillary movement, bilateral sagittal split osteotomy, with or without genioplasty. All patients had to have preoperative (T0) and at least 6 months postoperative (T1) cone-beam computed tomographies that were imported to Dolphin 3-dimensional (3D) software. The 3D voxel-based superimposition on the cranial base was performed for T0 and T1 to accurately measure the skeletal surgical movements. A virtual orthognathic surgery was performed on T0 to mimic the actual skeletal osteotomies using the treatment simulation tool in Dolphin 3D. A prediction 3D soft-tissue image (Tp) was generated based on the Dolphin virtual skeletal planning. The upper airway was segmented and exported as stereolithography surface files in both T1 and Tp. The measurements of the 3D volume of the airway were calculated and compared among T1 and Tp by using surface superimposition technique. Mean and standard deviations of upper airway volume were compared and correlated using paired t-test. RESULTS: There was no statistically significant difference between the upper airway volume of T1 and Tp. CONCLUSION: Dolphin 3D delivers accurate airway prediction which is an important step in 3D virtual planning.


Assuntos
Imageamento Tridimensional , Nariz/diagnóstico por imagem , Procedimentos Cirúrgicos Ortognáticos , Faringe/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Software
3.
J Oral Maxillofac Surg ; 78(9): 1629.e1-1629.e9, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32417317

RESUMO

PURPOSE: Ectodermal dysplasias (EDs) are a diverse set of hereditary conditions in which 2 or more ectodermal structures develop abnormally. The purpose of this study was to use cone-beam computed tomography (CBCT) scans to measure the pharyngeal airway volume and minimum cross-sectional area (MC) among patients with ED and compare them with healthy controls. PATIENTS AND METHODS: The pretreatment CBCT scans of 9 individuals with ED and 61 controls were analyzed. Lateral cephalograms were created from the CBCT volumes and then traced and compared between the 2 groups. Airway volumes were evaluated by Dolphin 3D software (Dolphin Imaging, Chatsworth, CA) to compare the total pharyngeal volume, nasopharyngeal volume, oropharyngeal volume, hypopharyngeal volume, and MC. The mean airway volumes of the 2 groups were compared, and the odds ratio and relative risk of having an MC of less than 100 mm2 in the ED group were calculated. RESULTS: Intraclass correlation analysis showed excellent inter-rater reliability. All cephalometric features of controls were within the norms of patients with ideal skeletal-dental relationships. Patients with ED displayed significantly lower values for SNA (angle between sella-nasion and nasion-A point) (P = .018), ANB (angle between nasion-A point and nasion-B point) (P = .002), L1-MP (angle between long axis of mandibular incisor and gonion-menton plane) (P = .013), and L1-NB (distance between mandibular incisor and perpendicular line between nasion and B point) (P < .001). Although the ED group exhibited slightly smaller airway volumes for all subregions, the differences were not statistically significant for total pharyngeal volume, nasopharyngeal volume, oropharyngeal volume, hypopharyngeal volume, or MC (P > .05). The odds of having an MC of less than 100 mm2 were almost 3 times greater among ED patients, and the relative risk of an MC of less than 100 mm2 among ED patients was double that of controls. CONCLUSIONS: Although the craniofacial structures of individuals with ED are characterized by maxillary and midface deficiency, the airway volumes among affected individuals may not be significantly different from those of unaffected controls. However, patients with ED displayed a higher risk of having an MC of less than 100 mm2, which may be of clinical significance and warrants further investigations with larger samples.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Displasia Ectodérmica , Cefalometria , Humanos , Imageamento Tridimensional , Faringe/diagnóstico por imagem , Reprodutibilidade dos Testes
5.
J Craniofac Surg ; 30(2): 525-528, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30358749

RESUMO

INTRODUCTION: Orthodontists and surgeons have been looking for more accurate methods to plan and predict surgical outcomes in patients with skeletal discrepancies. METHODS: The sample consisted of 20 subjects from the surgical clinic of a graduate orthodontic program who had been treated with Le Fort I maxillary movement, bisagittal split osteotomy, with or without genioplasty. All subjects had to have preoperative (T0) and at least 6 months postoperative (T1) cone-beam computed tomographies that were imported to Dolphin three-dimensional (3D) software version 11.9 in digital imaging and communications in medicine format. Three-dimensional voxel-based superimposition on the cranial base was performed for T0 and T1 to accurately measure the skeletal surgical movements. A virtual orthognathic surgery was performed on T0 to mimic the actual skeletal osteotomies using the treatment simulation tool in Dolphin 3D. A prediction 3D soft tissue image (Tp) was generated based on the Dolphin virtual skeletal planning. The differences between Tp and T1 for all patients were measured using linear and angular measurements visualized by surface mapping. RESULTS: Significant differences were found between Tp and T1 in Nasolabial angle, Soft tissue A point, and Subalar area. CONCLUSIONS: The soft tissue prediction accuracy after double jaw surgery using Dolphin 3D is limited in some areas, especially upper lip and base of the nose.


Assuntos
Face/anatomia & histologia , Imageamento Tridimensional , Maxila/cirurgia , Osteotomia de Le Fort , Software , Cirurgia Assistida por Computador , Adulto , Tomografia Computadorizada de Feixe Cônico , Feminino , Mentoplastia , Humanos , Imageamento Tridimensional/métodos , Lábio/anatomia & histologia , Masculino , Maxila/diagnóstico por imagem , Nariz/anatomia & histologia , Procedimentos Cirúrgicos Ortognáticos/métodos , Osteotomia de Le Fort/métodos , Adulto Jovem
6.
Am J Orthod Dentofacial Orthop ; 153(4): 505-511, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29602342

RESUMO

INTRODUCTION: Cortical bone thickness, bone width, insertion depth, and proximity to nerves are important factors when planning and placing orthodontic miniscrews. The objective of this study was to anatomically assess the mandibular buccal shelf in a white patient population as the insertion site for orthodontic miniscrews by investigating these 4 variables. METHODS: Measurements were made on cone-beam computed tomography scans of 30 white patients (18 girls, 12 boys; mean age, 14.5 ± 2 years). All measurements were taken adjacent to the distobuccal cusp of the first molar, and the mesiobuccal and distobuccal cusps of the second molar. Additionally, bone depth was measured at 2 height levels, 4 and 8 mm from the cementoenamel junction. Stereolithographic models of patients were superimposed on the cone-beam computed tomography volumes to virtually create an outline of the soft tissue on the cone-beam computed tomography image to allow identification of the purchase point height (mucogingival junction). The inferior alveolar nerve was digitally traced. Miniscrews (1.6 × 10 mm) were virtually placed at the buccal shelf, and their insertion depths and relationships to the nerve were assessed. Analysis of variance with post hoc analysis was used for data analysis. RESULTS: Insertion sites and measurement levels had significant impacts on both cortical bone thickness and bone width. Cortical bone thickness was typically greatest at the distobuccal cusp of the second molar. Bone width was also greatest at the distobuccal cusp of the second molar 8 mm from the cementoenamel junction. The greatest insertion depth was found again at the distobuccal cusp to the second molar, whereas the miniscrews had the greatest proximity to the nerve at this site also. CONCLUSIONS: The distobuccal cusp level of the mandibular second molar is the most appropriate site for miniscrew insertion at the buccal shelf in white patients.


Assuntos
Parafusos Ósseos , Osso Cortical/anatomia & histologia , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Procedimentos de Ancoragem Ortodôntica/instrumentação , Adolescente , Análise de Variância , Densidade Óssea , Criança , Tomografia Computadorizada de Feixe Cônico/métodos , Osso Cortical/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Nervo Mandibular/anatomia & histologia , Nervo Mandibular/diagnóstico por imagem , Maxila/diagnóstico por imagem , Maxila/cirurgia , Dente Molar/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica/métodos , Estereolitografia , Colo do Dente/diagnóstico por imagem , Colo do Dente/cirurgia , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem
8.
Am J Orthod Dentofacial Orthop ; 147(2): 264-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25636561

RESUMO

INTRODUCTION: The aim of this study was to evaluate the reliability of newly developed software in the assessment of orthodontic tooth movement 3 dimensionally. METHODS: The sample consisted of pretreatment and posttreatment computed tomography scans and plaster dental models of 20 orthodontic patients treated with a hyrax palatal expander as a part of their comprehensive orthodontic treatment. Dental-arch measurements, including arch widths, tooth inclinations, and angulation parameters, were measured on the scans using InvivoDental 3D imaging software (version 5.1; Motionview, Hixson, Tenn). The plaster dental models were laser scanned and superimposed, and measurements were obtained digitally using the new software. Agreement between the digital models and the computed tomography measurements was evaluated with intraclass correlation coefficients, paired t tests, and Bland-Altman plots. A P value of ≤0.05 was considered statistically significant. RESULTS: High agreement, a nonsignificant paired t test, and no indication of agreement discrepancies were observed for most of the measured parameters. CONCLUSIONS: The results confirmed that the new software program offers a reliable tool for dental-arch measurements obtained from 3-dimensional laser-scanned models.


Assuntos
Cefalometria/estatística & dados numéricos , Validação de Programas de Computador , Software , Técnicas de Movimentação Dentária/estatística & dados numéricos , Adolescente , Criança , Dente Canino/patologia , Arco Dental/patologia , Modelos Dentários/estatística & dados numéricos , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Imageamento Tridimensional/estatística & dados numéricos , Incisivo/patologia , Lasers , Dente Molar/patologia , Técnica de Expansão Palatina , Reprodutibilidade dos Testes , Estudos Retrospectivos , Rotação , Tomografia Computadorizada Espiral/estatística & dados numéricos , Torque , Interface Usuário-Computador
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