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2.
Am J Orthod Dentofacial Orthop ; 120(2): 144-8, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11500655

RESUMEN

The purpose of this study was to investigate the sagittal and vertical effects on the maxilla induced by surgically assisted rapid palatal expansion. Twenty patients (average age, 25.6 years) who required a surgically assisted rapid palatal expansion procedure were available for this study. Each patient was banded with a Haas-type palatal expander, maxillary surgery was performed, and the expander was activated. Presurgical and postexpansion lateral cephalograms were taken for each patient. The measurements of SNA, Frankfort horizontal-nasion-A point, sella-nasion-palatal plane, A-point-nasion-perpendicular (in millimeters), 1-nasion-A-point, 1-sella-nasion, 1-nasion-perpendicular (in millimeters) were made on each cephalogram, and the presurgical and postexpansion tracings were superimposed on the cranial base to determine the changes in the anterior nasal spine and posterior nasal spine positions. Results showed that from the presurgical cephalogram to the postexpansion cephalogram SNA, Frankfort horizontal-nasion-A point and A-point-nasion-perpendicular had a mean increase of 0.60 degrees (P <.05), 0.65 degrees (P <.05), and 0.55 mm (P <.05), respectively; 1-nasion-A-point decreased 2.18 degrees (P <.05) and 1-sella-nasion decreased 1.53 degrees (P <.05). No significant maxillary vertical displacement was noted from the first cephalogram to the second. In conclusion, surgically assisted RPE did not significantly affect the maxilla vertically; however, it did induce a slight forward movement of the maxilla and a slight retroclination of the maxillary incisors sagittally (P <.05).


Asunto(s)
Maxilar/anatomía & histología , Maxilar/cirugía , Procedimientos Quirúrgicos Orales , Técnica de Expansión Palatina , Adolescente , Adulto , Cefalometría , Femenino , Humanos , Incisivo/fisiopatología , Masculino , Variaciones Dependientes del Observador , Resultado del Tratamiento
8.
Artículo en Inglés | MEDLINE | ID: mdl-11307190

RESUMEN

It has been reported in the literature that certain species of bacteria (periodontopathogens) present in the subgingival plaque are associated with destructive periodontal disease. The purpose of this study was to investigate and compare the presence and proportional distribution of periodontopathogens in the subgingival plaque of adult crowded versus non-crowded dental regions. Thirty adult patients with anterior dental crowding were selected from the Orthodontic Clinic of the University of Pennsylvania. After orthodontic records were taken and the periodontal examination was performed, subgingival plaque samples were collected from crowded (experimental) and contralateral non-crowded regions (control) of each patient. The presence of 9 periodontopathic species, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, Campylobacter rectus, Capnocytophaga species, Fusobacterium species, Peptostreptococcus micros, Porphyromonas gingivalis, and Bacteroides forsythus, was determined using culture and immunofluorescence techniques. The bacterial morphotype was also determined by the use of dark-field microscopy. It was found that supragingival plaque accumulation in crowded regions was significantly greater than in non-crowded regions. Analysis of the bacteria showed that the samples from crowded regions consistently contained more species of periodontopathogens than the samples from non-crowded regions. Morphologically, more spirochetes and motile rods were present in the crowded-region samples. In terms of the presence of individual periodontopathogens, Fusobacterium species, Capnocytophaga species, C rectus, and P micros were significantly more common in the crowded samples than in the non-crowded samples. It was concluded that: (1) more plaque accumulated in crowded areas; (2) more species of periodontopathogens were present in the subgingival plaque of crowded regions; (3) morphologically, more spirochetes and motile rods were present in crowded areas; and (4) Fusobacterium species, Capnocytophaga species, C rectus, and P micros were present more often in crowded areas than in non-crowded areas (P < 0.05).


Asunto(s)
Placa Dental/microbiología , Maloclusión/microbiología , Adolescente , Adulto , Aggregatibacter actinomycetemcomitans/aislamiento & purificación , Campylobacter/aislamiento & purificación , Capnocytophaga/aislamiento & purificación , Distribución de Chi-Cuadrado , Recuento de Colonia Microbiana , Placa Dental/complicaciones , Índice de Placa Dental , Eikenella corrodens/aislamiento & purificación , Femenino , Técnica del Anticuerpo Fluorescente , Fusobacterium/aislamiento & purificación , Humanos , Masculino , Maloclusión/complicaciones , Persona de Mediana Edad , Peptostreptococcus/aislamiento & purificación , Prevotella intermedia/aislamiento & purificación
11.
Am J Orthod Dentofacial Orthop ; 116(3): 346-51, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10474109

RESUMEN

An in vitro study was conducted to evaluate the accuracy of bracket placement for direct and indirect bonding techniques. Nineteen sets of duplicated Class II malocclusion models were divided into three groups: (1) one set for ideal bracket placement, (2) nine sets for direct bonding on mannequins, and (3) nine sets for indirect bonding. Both direct and indirect bonding were performed on all teeth except molars by nine faculty members from the Department of Orthodontics, University of Pennsylvania. The position of each bonded bracket from these two bonding groups was compared with that of the same tooth from the ideal group and to each other in terms of bracket height, mesiodistal position, and angulation. Our results indicated that both direct and indirect bonding techniques failed to execute ideal bracket placement. On individual teeth, there was no statistically significant difference in the accuracy of bracket placement between these two bonding techniques except for upper right second premolar and lower left central incisor, where indirect bonding yielded better results in bracket height (P < .05), and for lower left central incisor where indirect bonding was better in mesiodistal position (P < .05), and for upper right lateral incisor where direct bonding was closer to the ideal in angulation (P < .05). Overall, indirect bonding showed better bracket placement in bracket height (P < .05), whereas, no statistically significant difference was found between them regarding the angulation and mesiodistal position.


Asunto(s)
Recubrimiento Dental Adhesivo/métodos , Soportes Ortodóncicos , Humanos , Maloclusión Clase II de Angle/terapia , Modelos Dentales , Reproducibilidad de los Resultados
13.
Angle Orthod ; 69(2): 141-6, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10227554

RESUMEN

Needle electromyography (NEMG) was used to compare the effects of the Hawley bite plane (HBP) and superior repositioning splint (SRS) on the ipsilateral masseter and anterior temporal muscles at rest and in maximum closure. Twenty adult subjects were randomly divided into two groups of 10. One group wore the HBP for 8 hours per day and the other group wore SRS for the same time period. After 2 weeks of use, NEMG was conducted on the ipsilateral masseter and temporal muscles with and without the device in place. Each group then wore the other appliance for an identical period and underwent NEMG. Both appliance designs produced decreases in electromyographic responses during use. Individuals in the HBP group showed a 48.6% decrease in anterior temporal activity and a 34.1% decrease in masseter muscle activity. The SRS group demonstrated 23.5% and 16.2% decreases in anterior temporal and masseter muscles activities, respectively. This is the first report of the use of NEMG as a mode of assessment of muscle activity in human or animal subjects.


Asunto(s)
Músculo Masetero/fisiología , Ferulas Oclusales , Retenedores Ortodóncicos , Músculo Temporal/fisiología , Adulto , Análisis de Varianza , Electromiografía/instrumentación , Femenino , Humanos , Masculino
14.
Semin Orthod ; 5(3): 171-80, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10860069

RESUMEN

This article emphasizes the critical importance of the skeletal differential between the width of the maxilla and the width of the mandible. Undiagnosed transverse discrepancy leads to adverse periodontal response, unstable dental camouflage, and less than optimal dentofacial esthetics. Hundreds of adult retreatment patients corrected for significant maxillary transverse deficiency using surgically assisted maxillary expansion (similar to osseous distraction) has produced excellent stability. Eliciting tooth movement for children (orthopedics, lip bumper, Cetlin plate) in all three planes of space by muscles, eruption, and growth, develops the broader arch form (without the mechanical forces of fixed or removable appliances) and has also demonstrated impressive long term stability.


Asunto(s)
Maloclusión/terapia , Mandíbula/fisiopatología , Técnica de Expansión Palatina , Adolescente , Adulto , Cefalometría , Niño , Arco Dental/patología , Femenino , Recesión Gingival/etiología , Humanos , Masculino , Maloclusión/complicaciones , Evaluación de Resultado en la Atención de Salud , Recurrencia , Valores de Referencia , Análisis de Regresión , Retratamiento
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