41 |
PREVALENCE, LOCATION, AND MORPHOLOGY OF MAXILLARY SINUS SEPTA IN A UNITED STATES PATIENT POPULATIONAlRoomi, Abrar January 2017 (has links)
Objectives: The presence of sinus septa may cause complications in maxillary sinus elevation surgery such as perforations. CBCT is important for planning the size, shape, and position of the sinus septa, and help separation of the sinus membrane from the bony septum. The purpose of this study is to determine the prevalence, location and morphology of maxillary sinus septa in patients of Temple University Kornberg School of Dentistry. Materials and Methods: Eight hundred and twenty one scans taken in Temple University Kornberg School of Dentistry between 2009 to July 31, 2013 were evaluated by use of the iCAT software. Age, gender, ethnicity, and dentition status were also evaluated to determine potential relationship of the presence of sinus septa. Results: This study included 680 patients subdivided by gender into 360 female and 320 male, and subdivided by ethnicity into 408 Caucasian, 61 Asian, 51 Hispanic, and 160 African Americans. Septa were present in 303 of 680 patients (44.56%) and 485 of 1360 sinuses (35.7%) evaluated. 26.76% of patients with one or multiple sinus septa were present on both sides of the sinus, and 17.79% of patients with one or multiple septa were present on either right or left side only. Septa height has a mean of 5.26 mm (range of 1.2 to 22.30 mm). Septa were located in premolar, molar, and retromolar regions in 43.4%, 42.03% and 14.6 % respectively. The most common location of the septa is the second premolar region. Orientation of septa was vertical in 67.8 %, transverse 31.68 %, and horizontal 0.005% of cases. Complete septa were found in only 0.01 % of patients evaluated. Conclusions: Incidence of septa was found in 44.56% of the scans. The age, gender, and ethnicity factors are not statistically significant. However, according to the Wald test, the prevalence of septa in Caucasian and Hispanic groups are statistically significant (p< 0.05) from African Americans. Prior to sinus augmentation surgery, CBCT scans should be carefully evaluated for the septa location and height to prevent surgical complication such as perforations. / Oral Biology
|
42 |
A Comparative Study of Rotary Instrumentation of the Maxillary First Premolar Buccal Root Utilizing Cone Beam Computed TomographyZigo, Stephan 07 April 2011 (has links)
The study objective was to determine cementum-dentin wall thickness along the furcation groove in maxillary bifurcated first premolars after preparation with three successively larger, 0.04 tapered, nickel titanium rotary files. Pre-instrumentation and post-instrumentation imaging was accomplished utilizing Cone Beam Computed Tomography. All data was analyzed using an ANOVA. Instrumentation resulted in a significant reduction in dentin-cementum wall thickness (p < .001). At mid-groove, predicted dentin-cementum wall thickness (95% CI) was equal to or less than the proposed standard (0.50 mm) for apical file sizes 30, 35, and 40 respectively. Instrumentation of the mid-groove in maxillary first premolars reduces dentin-cementum wall thickness to levels that may be insufficient to ensure tooth integrity.
|
43 |
Three-Dimensional Photographic Evaluation of Immediate Soft Tissue Changes Following Rapid Maxillary ExpansionGranillo, Nathan 06 June 2011 (has links)
The skeletal and dental changes associated with rapid maxillary expansion (RME) are well documented. Effects on the soft tissues and the potential impact on facial esthetics have not been well researched. The purpose of this study was to evaluate immediate changes in facial soft tissues as a result of RME by comparing threedimensional digital photogrammetric images before and after RME treatment. The 3dMDface System was used to obtain photographic images of 21 patients (mean age = 11.8 years) before and after RME treatment for transverse maxillary deficiency. A control group of 13 patients (mean age = 12.7 years) also had two images taken at a similar time interval. Mean expansion was 6.5 mm in the RME patients. Intercanthal distance, nose width, and intercommissural width changed significantly in the RME patients from T0 to T1 (P = 0.011, P = 0.050, and P = 0.003, respectively). Intercommissural width, however, was the only measure that significantly changed as compared with the control group (P = 0.041). Changes in intercanthal distance and nose width were significantly related to the amount of expansion achieved (R2 = 0.428, P = 0.0013 and R2 = 0.501, P = 0.0003, respectively).
|
44 |
ESTHETIC PREFERENCES OF MAXILLARY INCISOR LABIOLINGUAL INCLINATION ACROSS RACESBarcoma, Elvi M 01 January 2015 (has links)
Abstract
ESTHETIC PREFERENCES FOR MAXILLARY INCISOR LABIOLINGUAL INCLINATION ACROSS RACES
by Elvi Marie Barcoma, D.D.S.
A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University
Virginia Commonwealth University, 2015
Major Director: Bhavna Shroff, D.M.D., M.Dent.Sc, Program Director, Orthodontics
Objective: To determine if people of different racial backgrounds prefer different amounts of
maxillary incisor labiolingual inclination from a smiling profile view.
Materials and Methods: An electronic survey was created with smiling profile images of an African-American female and a White female with varying degrees of maxillary incisor labiolingual inclination. Images were ranked from most attractive to least attractive.
Results: There was no statistically significant difference in the overall preference for maxillary incisor labiolingual inclination between African-American and White evaluators or between genders. The estimated optimal incisal inclination across races was -8.1°.
Conclusions: There was no clinically significant difference in the estimated optimal inclination across races or between genders. The average of the top three maxillary incisor inclinations ranged between -10° and -5°. The majority of evaluators preferred retroclined maxillary incisors over proclined maxillary incisors.
|
45 |
Estudo comparativo de duas técnicas de enxerto autógeno utilizando piezocirurgia para levantamento de seio maxilar / Comparative study of two autogenous graft techniques using piezosurgery for sinus liftingCamargo Filho, Geraldo Prestes de 28 May 2010 (has links)
A técnica de levantamento de seio maxilar apresenta como uma possível complicação a perfuração da membrana sinusal. A utilização de dispositivos ultrassônicos apresenta-se como uma interessante ferramenta, particularmente segura e eficiente para realização das ostectomias de parede sinusal e divulsão de membrana sinusal. O presente trabalho teve por objetivo comparar duas técnicas que utilizam a cirurgia ultrassônica para realização de enxerto autógeno para levantamento de seio maxilar. Dez coelhos foram utilizados no estudo, sendo que um deles não foi submetido a procedimento cirúrgico. Os nove coelhos operados tiveram os seios maxilares preenchidos com enxertos autógenos coletados de díploe externa de calota craniana, nas formas particulado do lado direito e raspado do lado esquerdo, ambos com aparelho ultrassônico. Os dados de densidade óssea nos seios maxilares esquerdo e direito, obtidos por meio de tomografia computadorizada nos sentidos transversal e longitudinal, registrados 90 dias após a realização dos enxertos foram comparados estatisticamente. Cortes histológicos das áreas enxertadas foram realizados com finalidade descritiva. Não houve diferenças estatisticamente significantes entre as técnicas de enxerto que utilizaram osso raspado e particulado coletado por meio de dispositivo ultrassônico da calota craniana de coelhos. O aspecto histológico observado após 90 dias foi semelhante nos dois grupos, mostrando tecido ósseo maduro em meio a tecido conjuntivo frouxo. Os procedimentos transoperatórios nos levaram a concluir que o ultrassom piezoelétrico mostrou-se um instrumento seguro na abordagem cirúrgica do seio maxilar de coelhos, permitindo a manutenção da integridade da membrana sinusal durante as manobras cirúrgicas. / Maxillary sinus lifting is a technique which presents as a possible complication the sinus membrane perforation. The use of ultrasonic devices is presented as an interesting tool, particularly safe and efficient to perform ostectomies of sinus wall and dissection of sinus membrane. This study aimed to compare two techniques that used ultrasound surgery to perform autogenous graft for maxillary sinus lifting. Ten rabbits were used in the study, one of which did not undergo surgery. The other nine rabbits had their maxillary sinuses filled with autogenous bone grafts collected from the external skull diploe in particulate form on the right side and shaved on the left side, both with ultrasonic device. Data on bone density in left and right maxillary sinus, obtained by computed tomography in transverse and longitudinal sections, recorded 90 days after the grafts, were compared statistically. Histological sections of the grafted areas were performed with descriptive purposes. There were no statistically significant differences between the two techniques that used shaved and particulate bone collected by means of ultrasonic device of the skull of rabbits. Histological aspects after 90 days were similar in both groups, showing mature bone through a fibrous connective tissue. Operatory assessment procedures leads us to conclude that the piezoelectric ultrasound showed as a safe tool in the surgical approach of the maxillary sinus of rabbits, allowing the maintenance of sinus membrane integrity during surgical procedures.
|
46 |
Alterações dos tecidos moles após avanço de maxila em pacientes com fissura labiopalatina / Soft tissue changes after maxillary advancement in patients with cleft lip and palateTanaka, Annie Karoline de Oliveira 16 June 2015 (has links)
Indivíduos com fissura labiopalatina frequentemente necessitam de cirurgia de avanço maxilar para correção do desequilíbrio facial e das relações oclusais. A fibrose cicatricial do lábio superior, resultante de cirurgias prévias para fechamento da fissura, impede o crescimento ósseo adequado, causando deficiência maxilar significativa. Embora diversos estudos avaliem o perfil mole de pacientes submetidos à cirurgia ortognática, a maioria não inclui em sua amostra pacientes com fissura labiopalatina. A resposta dos tecidos moles em pacientes fissurados é incerta e de difícil previsibilidade no planejamento cirúrgico, sendo um fator limitante no resultado final. No presente trabalho, a análise cefalométrica dos tecidos moles foi realizada com o objetivo de estabelecer relações entre o avanço do tecido mole e tecido duro em pacientes fissurados, além de estudar o comportamento dessas estruturas frente ao avanço maxilar. O estudo foi observacional e descritivo e contou com uma amostra de 87 pacientes fissurados tratados cirurgicamente por meio de osteotomia Le Fort I com avanço maxilar. O tempo pós-operatório mínimo para estudo foi de 6 meses. As telerradiografias com tempos operatórios distintos foram digitalizadas e o traçado cefalométrico foi realizado através do software Dolphin Imaging. Para o cálculo do avanço maxilar médio, uma ferramenta do software foi utilizada permitindo a sobreposição das telerradiografias. A amostra foi então dividida de acordo com a amplitude de movimento e os resultados em tecido mole analisados. As maiores relações tecido mole/duro foram obtidas em avanços menores ou iguais a 5,0 mm. O overjet, overbite e o comprimento do lábio superior aumentaram enquanto que o nariz diminuiu em todas as amplitudes de movimento. Não houve alteração significativa no avanço do lábio superior, independente da quantidade de avanço. Em avanços de até 5,0 mm as repercussões em tecido mole foram mínimas, manifestando-se em maiores avanços. Nenhuma correlação significativa foi encontrada entre qualquer variável estudada e o avanço maxilar. O estudo revelou uma visão geral do comportamento das estruturas do tecido mole em pacientes fissurados frente à cirurgia ortognática. Tais informações auxiliam no planejamento cirúrgico prévio e favorecem a obtenção de perfil facial condizente ao planejado. / Individuals with cleft lip and palate frequently require maxillary advancement surgery to correct facial imbalance and occlusal relationship. The scarring of upper lip, resulting from previous cleft closure surgery, inhibits proper bone growth causing significant maxillary deficiency. Although several studies evaluate the soft tissue profile in patients undergoing orthognathic surgery, most of them do not include in their sample patients with cleft lip and palate. The soft tissue response in cleft patients is uncertain and difficult to predict in surgical planning, being a limiting factor in the final result. In this study the cephalometric analysis of soft tissues was performed in order to define relationships between the advancement of soft tissue and hard tissue in cleft patients. The behavior of these structures regarding to maxillary advancement was also analyzed. The study was observational and descriptive and included a sample of 87 patients treated surgically by Le Fort I osteotomy with maxillary advancement. The minimum post-operative time to study was 6 months. Lateral cephalometric radiographs with distinct post-surgical times were scanned and cephalometric tracing was performed by Dolphin Imaging software. To calculate the average maxillary advancement, a software tool was used to allow the overlay of radiographs. Then, the sample was divided according to advancement amplitude and the results in soft tissue were analyzed. The highest soft/hard tissue ratios were obtained in advancements smaller than or equal to 5.0 mm. Overjet, overbite and upper lip length increased while the nose decreased in all advancement amplitude. There was no significant change in upper lip advancement, regardless of the measurement of maxillary advancement. In advances of up to 5.0 mm the effects in soft tissue were minimal, manifesting in greater advances. No significant correlation was found between any variable studied and the maxillary advancement. The study revealed an overview of the behavior of soft tissue structures in cleft patients undergoing to orthognathic surgery. This information supports presurgical planning and it benefits into getting the planned facial profile.
|
47 |
Recidiva do apinhamento ântero-superior nas más oclusões de classe I e classe II tratadas ortodonticamente sem extrações / Relapse of maxillary anterior crowding in Class I and Class II malocclusion treated orthodontically without extractionsGuirro, Willian Juarez Granucci 18 February 2009 (has links)
O presente estudo objetivou comparar retrospectivamente a estabilidade póscontenção do alinhamento dos incisivos ântero-superiores em pacientes Classe I e Classe II de Angle. A amostra consistiu-se de 38 pacientes de ambos os gêneros, tratados sem extrações e mecânica Edgewise. A amostra foi dividida em dois grupos: Grupo 1 (Classe I) constituído por 19 pacientes (12 do gênero feminino e 7 do gênero masculino), com idade inicial média de 13,06 anos (d.p. = ± 1,27), portadores da má oclusão de Classe I com apinhamento ântero-superior inicial maior que 3mm. Grupo 2 (Classe II) apresentando 19 pacientes (14 do gênero feminino e 5 gênero masculino), com idade inicial de 12,54 (d.p. = ± 1,37), portadores da má oclusão de Classe II, e também com apinhamento ântero-superior inicial maior que 3mm. Foram medidos nos modelos de estudo das fases pré (T1), pós-tratamento (T2) e pós-contenção (T3), o índice de irregularidade de Little, as distâncias intercaninos e entre os primeiros e segundos pré-molares, a distância intermolares e o comprimento do arco superior. Após a obtenção dos dados, realizou-se a análise estatística. Para a comparação intragrupo nos 3 tempos de avaliação, utilizou-se a análise de variância a um critério de seleção, e em caso de resultado significante, o teste de Tukey. A comparação intergrupos foi realizada por meio de testes t independentes. Para verificação da presença de correlação entre a recidiva do apinhamento ântero-superior e a recidiva das variáveis: distâncias intercaninos, interpré-molares, intermolares e comprimento do arco, utilizou-se o teste de correlação de Pearson. Os resultados evidenciaram maior estabilidade do tratamento no grupo 2 (Classe II), pois durante o período pós-contenção, foi observada uma menor recidiva do apinhamento dos dentes ântero-superiores no grupo 2 (0,80mm) do que no grupo 1 (1,67mm). Concluiu-se que o tratamento do apinhamento dos dentes ântero-superiores é mais estável na má oclusão de Classe II do que na má oclusão de Classe I. / The present study aimed to retrospectively compare the postretention stability of maxillary anterior incisors alignment in Angle Class I and Class II patients. Sample comprised 38 patients of both genders, treated nonextraction and edgewise mechanics. Sample was divided into two groups: Group 1 (Class I) comprised 19 patients (12 females and 7 males), at a mean age of 13,06 years (d.p. = ± 1,27), with Class I malocclusion and initial maxillary anterior crowding greater than 3mm. Group 2 (Class II) comprised 19 patients (14 females and 5 males), at a mean age of 12,54 (d.p. = ± 1,37), with Class II malocclusion, and also with a initial maxillary anterior crowding greater than 3mm. It was measured the dental casts of pre (T1), posttreatment (T2) and postretention (T3), the Little irregularity index, intercanine distance and between first and second premolars, intermolar distance and maxillary arch length. After obtainment of data, the statistical analysis was performed. For intragroup comparison among the three times of evaluation, it was used the one-way ANOVA followed by Tukey test in case of a significant result. Intergroup comparison was performed by independent t tests. To verify the presence of correlation among the relapse of maxillary anterior crowding and the relapse of the variables: intercanine, interpremolar and intermolar distances and arch length, the Pearson correlation test was used. Results evidenced greater stability of treatment in group 2 (Class II), because during the postretention period, it was observed a lesser relapse of maxillary anterior crowding in group 2 (0,80mm) than in group 1 (1,67mm). It was concluded that treatment of maxillary anterior crowding is more stable in Class II malocclusion than in Class I malocclusion.
|
48 |
Análise tomográfica e histomorfométrica comparativa entre enxerto ósseo autógeno e enxerto ósseo xenogênico em cirurgia de levantamento de seio maxilar em coelhosSicca, Cristina Miguel 25 February 2005 (has links)
O objetivo deste trabalho foi avaliar a neoformacão óssea induzida por um xenoenxerto bovino composto comparativamente ao ósseo autógeno, em cirurgias de levantamento de seio maxilar em coelhos. Nesse estudo utilizouse o seio maxilar de 18 coelhos machos, sendo que no seio maxilar esquerdo foi colocado 200mg de osso autógeno córtico-medular triturado e no seio maxilar direito, o biomaterial, de origem bovina, composto por matriz orgânica cortical e inorgânica medular, \'pool\' de BMPs e colágeno (Gen- Tech®). Realizou-se análise tomográfica por tomógrafo computadorizado (TC) para avaliar a densidade óptica comparativamente entre os grupos e períodos experimentais, a histológica descritiva para verificar a resposta tecidual frente aos materiais implantados e a histomorfométrica para obter os dados de densidade de volume de tecido ósseo neoformado, tecido conjuntivo e/ou granulação, material residual e tecido mielóide. Os resultados obtidos pela TC demonstraram densidade óptica cerca de 2 vezes maior no grupo teste. Na análise histológica observou-se infiltrado inflamatório apenas no período de 2 semanas do grupo teste e exclusivamente ao redor do componente orgânico do biomaterial. Quanto a neoformação óssea, não houve diferença estatisticamente significativa entre os dois grupos experimentais ou ao longo dos períodos, no entanto a área de tecido mielóide foi cerca de 2 vezes maior no grupo controle. Considerando-se os limites do modelo experimental e da técnica empregada podemos concluir que o biomaterial Gen-Tech® é potencialmente indicado como substituto ósseo em cirurgias de levantamento de seio maxilar, uma vez que promove uma neoformação óssea similar à do osso autógeno. / The purpose of this study was to evaluate new bone formation induced by a bovine xenograft compared to autogenous bone in maxillary sinus augmentation in rabbits. The maxillary sinus of 18 male rabbits were used, whereas the left sinus was filled with 200mg of a mixture of cortical and medullar autogenous bone and the right sinus was filled with a mix of organic and inorganic bovine matrix, plus \'pool\' of BMPs and collagen (Gen-Tech®). Computer tomography (CT) analysis was realized to evaluate and compare the optical density among the groups and experimental periods; descriptive histologic analysis was used to verify the tissue response to the materials implanted. In addition, histomorphometric analysis was realized to evaluate volume density of the newly formed bone, connective tissue and/or granulation tissue, residual material and myeloid tissue. The results obtained in the CT demonstrated an optical density approximately 2 times greater in the test groups. Histological analysis revealed an inflammatory infiltrate at 2 weeks in the test group and exclusively around the organic portion of the material. Regarding new bone formation, no statistical differences were observed among the two experimental groups or throughout the experimental periods. However the area of myeloid tissue was 2 times greater in the control group. Considering the limits of the experimental model and technique used in this study, it is possible to conclude that Gen-Tech® is a biomaterial with potential applications as a bone substitute in maxillary sinus augmentation once it is able to promote the formation of new bone similarly to autogenous bone.
|
49 |
Avaliação da alteração da via aérea superior e da estabilidade óssea em pacientes submetidos à Osteotomia Le Fort III modificada associada à Osteotomia Le Fort I para tratamento da hipoplasia do terço médio da face /Boos Lima, Fernanda Brasil Daura Jorge January 2016 (has links)
Orientador: Eduardo Hochuli Vieira / Resumo: A hipoplasia maxilar geralmente resulta em uma maloclusão Classe III de Angle, podendo, em alguns casos, apresentar mordida aberta anterior. O grau de deficiência de crescimento orbital, maxilar e ao nível oclusal raramente é uniforme nos três planos. Para corrigir discrepâncias severas e atingir uma relação intermaxilar adequada, com oclusão estável, a osteotomia Le Fort III está indicada para tratamento de pacientes sindrômicos e não sindrômicos. A técnica segue um desenho semelhante a uma fratura Le Fort III, descrita por René Le Fort. Devido à mobilização de todo segmento esquelético do terço médio, apresenta resultados estéticos mais favoráveis em comparação com avanço apenas do segmento maxilar. Este trabalho tem o propósito de avaliar comparativamente, por meio de análise tomográfica retrospectiva, a alteração das vias aéreas superiores e a estabilidade óssea em pacientes não sindrômicos submetidos à osteotomia Le Fort III modificada associada à osteotomia Le Fort I para tratamento da hipoplasia do terço médio da face. / The maxillary hypoplasia generally results in an Angle Class III malocclusion, and may in some cases produce anterior open bite. The level of orbital, maxillary and occlusal growth deficiency is rarely uniform in all three planes. To correct severe discrepancies and achieve adequate intermaxillary relation, with stable occlusion, Le Fort III osteotomy is indicated for the treatment of syndromic and non-syndromic patients. The technique is similar to a Le Fort III fracture, described by René Le Fort. Due to the mobilization of the entire skeletal segment of the facial middle third, presents more favorable cosmetic results compared to advancement of only the maxillary segment. This retrospective work aims to compare, using computed tomography, the change of the superior airway and the stability of the bone advancement in non-syndromic patients who underwent modified Le Fort III osteotomy associated with the Le Fort I osteotomy...(Complete abstract electronic sccess below) / Doutor
|
50 |
Comparison between the alpha angle of the maxillary impacted canines on panoramic radiographs and cone beam computed tomographyAlenazi, Khaled January 2019 (has links)
Magister Chirurgiae Dentium (MChD) / There is a paucity of studies that make use of the alpha angle as a diagnostic tool to assist with
the interceptive treatment, prognosis, treatment duration and surgical outcome of possible
maxillary canine impaction in orthodontics. While the literature is replete with studies that
utilise the sector method, the alpha angle is an alternative approach to assess the possible
eruptive outcome of the unerupted canine.
It has been reported that if the alpha angle is greater than 25°, there is the possibility of external
root resorption. However, if the alpha angle is more than 31°, the prospect of canine eruption
decreases even if the deciduous canine is extracted as an interceptive measure.
The dental pantomograph has historically been used to predict canine eruption or possible
impaction. The use of this method, however, is wrought with limitations. These limitations
include magnification, distortion and blurred images. The use of cone-beam computed
tomography has been advocated as a means to overcome these limitations.
|
Page generated in 0.0727 seconds