O propósito do presente estudo foi determinar, radiograficamente, os efeitos da desprogramação neuromuscular, por meio do uso da placa miorrelaxante superior, na posição craniocervical. A desprogramação neuromuscular foi feita objetivando-se realizar o diagnóstico ortodôntico com a mandíbula em relação cêntrica (RC), de acordo com filosofia de Roth (1981). Foram avaliados 39 indivíduos assintomáticos, com maloclusões Classe I de Angle, separados em dois grupos, o controle, contendo 15 indivíduos, com média de idade de 26 anos, não submetidos a qualquer forma de tratamento, e o tratado, contendo 24 indivíduos, com média de idade de 23 anos e 10 meses, submetidos à desprogramação neuromuscular. De cada paciente, foram obtidas duas telerradiografias em norma lateral, na posição natural da cabeça (PNC). No grupo controle, o intervalo médio entre ambas foi 6 meses e 17 dias. No grupo tratado, a primeira telerradiografia foi realizada previamente, e a segunda, após a desprogramação neuromuscular. O tempo médio de uso da placa miorrelaxante foi de 6 meses e 7 dias. A análise cefalométrica craniocervical foi realizada avaliando-se as angulações craniovertical (SN/VER), craniocervical (OPT/SN e CVT/SN), cervicohorizontal (OPT/HOR e CVT/HOR) e o ângulo da curvatura cervical (OPT/CVT). Concluíu-se que houve extensão significativa da cabeça, tanto em relação à linha vertical verdadeira, demonstrada pelo aumento do ângulo SN/VER, quanto à coluna cervical, demonstrada pelo aumento do ângulo CVT/SN. A coluna cervical apresentou alteração significativa em sua inclinação, em relação à linha horizontal verdadeira, demonstrado pelo aumento do ângulo CVT/HOR. Não houve alteração significativa da curvatura cervical. Foram, ainda, observadas correlações significativas entre as alterações das variáveis SN/VER e OPT/HOR, SN/VER e CVT/HOR, SN/VER e CVT/SN, OPT/CVT e OPT/HOR, OPT/CVT e OPT/SN, OPT/HOR e CVT/HOR, OPT/HOR e OPT/SN, assim como OPT/SN e CVT/SN. / The purpose of this study was to determine, radiographically, the effect of neuromuscular deprogramming, through the use of an upper occlusal splint, on the craniocervical position. Neuromuscular deprogramming was performed in order to carry out orthodontic diagnosis with the mandible in centric relation (CR), according to Roth’s philosophy. Thirthy nine asymptomatic individuals, presenting Angle's Class I malocclusion, were evaluated. The sample was allocated into two groups, the control or untreated group (n=15), with mean age of 26 years, that was followed about 6 months and 17 days, and the treated group (n=24), with mean age of 23 years and 10 months. Two lateral radiographs in natural head position (NHP) were taken from each subject, one before and the other one after neuromuscular deprogramming. The average usage period of the occlusal splint was 6 months and 7 days. Craniocervical cephalometric analysis was carried out by evaluating the craniovertical (SN/VER), craniocervical (OPT/SN and CVT/SN), and cervicohorizontal (OPT/HOR and CVT/HOR) angles, as well as the angle of the cervical curve (OPT/CVT). No significant changes were seen in the control group. It was concluded that there was a significant extension of the head, both in relation to the true vertical line, as demonstrated by the increase of the SN/VER angle, and to the cervical column, as demonstrated by the increase of the CVT/SN angle. Likewise, the cervical column showed significant backward inclination in relation to the true horizontal line, as demonstrated by increase of the CVT/HOR angle. No significant alteration of the cervical curve was observed. In addition, significant correlation coefficients were observed between the differences of the pre- and post-deprogramming values of the measurements the measurements SN/VER and OPT/HOR, SN/VER and CVT/HOR, SN/VER and CVT/SN, OPT/CVT and OPT/HOR, OPT/CVT and OPT/SN, OPT/HOR and CVT/HOR, OPT/HOR and OPT/SN, and OPT/SN and CVT/SN.

Commonly used craniofacial reference planes such as Frankfort Horizontal (FH) and sella nasion (SN) have shortcomings including their variable inter-individual orientation when related to true horizontal (HOR). Therefore, the aim of this study was to evaluate the potential usefulness of a range of craniofacial reference planes to HOR including those which have not been investigated before: Krogman-Walker line (KW line), neutral horizontal axis, foramen magnum line and posterior maxillary plane. A sample of 57 (38 female, 19 males) consecutive, pre-treatment orthodontic subjects aged 12 to 18 were photographically recorded in a standing mirror guided natural head position (NHP). Cephalograms taken at the same time were traced, oriented to a plumb line (true vertical) transferred from the photograph, and measured for statistical analysis. Thirty nine of these subjects were photographically recorded 2 months later to test the reproducibility of NHP. The results showed that the variability of the 11 selected craniofacial reference planes related to HOR was generally high. The planes illustrating lowest variability to HOR were FH and KW line with standard deviations of 4.6° and 4.7°, respectively. These, however, showed about double the variation in NHP reproducibility (Dahlberg 2.1°). The KW line and palatal plane were also oriented closest to HOR on average. Therefore, KW line and palatal plane are potential substitutes for the commonly used reference planes in the absence of a reliable NHP. However, NHP still represents a more valid craniofacial reference system than the investigated reference planes. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297323 / Thesis (D.Clin.Dent.) - School of Dentistry, (Orthodonitics), 2007

O propósito do presente estudo foi determinar, radiograficamente, os efeitos da desprogramação neuromuscular, por meio do uso da placa miorrelaxante superior, na posição craniocervical. A desprogramação neuromuscular foi feita objetivando-se realizar o diagnóstico ortodôntico com a mandíbula em relação cêntrica (RC), de acordo com filosofia de Roth (1981). Foram avaliados 39 indivíduos assintomáticos, com maloclusões Classe I de Angle, separados em dois grupos, o controle, contendo 15 indivíduos, com média de idade de 26 anos, não submetidos a qualquer forma de tratamento, e o tratado, contendo 24 indivíduos, com média de idade de 23 anos e 10 meses, submetidos à desprogramação neuromuscular. De cada paciente, foram obtidas duas telerradiografias em norma lateral, na posição natural da cabeça (PNC). No grupo controle, o intervalo médio entre ambas foi 6 meses e 17 dias. No grupo tratado, a primeira telerradiografia foi realizada previamente, e a segunda, após a desprogramação neuromuscular. O tempo médio de uso da placa miorrelaxante foi de 6 meses e 7 dias. A análise cefalométrica craniocervical foi realizada avaliando-se as angulações craniovertical (SN/VER), craniocervical (OPT/SN e CVT/SN), cervicohorizontal (OPT/HOR e CVT/HOR) e o ângulo da curvatura cervical (OPT/CVT). Concluíu-se que houve extensão significativa da cabeça, tanto em relação à linha vertical verdadeira, demonstrada pelo aumento do ângulo SN/VER, quanto à coluna cervical, demonstrada pelo aumento do ângulo CVT/SN. A coluna cervical apresentou alteração significativa em sua inclinação, em relação à linha horizontal verdadeira, demonstrado pelo aumento do ângulo CVT/HOR. Não houve alteração significativa da curvatura cervical. Foram, ainda, observadas correlações significativas entre as alterações das variáveis SN/VER e OPT/HOR, SN/VER e CVT/HOR, SN/VER e CVT/SN, OPT/CVT e OPT/HOR, OPT/CVT e OPT/SN, OPT/HOR e CVT/HOR, OPT/HOR e OPT/SN, assim como OPT/SN e CVT/SN. / The purpose of this study was to determine, radiographically, the effect of neuromuscular deprogramming, through the use of an upper occlusal splint, on the craniocervical position. Neuromuscular deprogramming was performed in order to carry out orthodontic diagnosis with the mandible in centric relation (CR), according to Roth’s philosophy. Thirthy nine asymptomatic individuals, presenting Angle's Class I malocclusion, were evaluated. The sample was allocated into two groups, the control or untreated group (n=15), with mean age of 26 years, that was followed about 6 months and 17 days, and the treated group (n=24), with mean age of 23 years and 10 months. Two lateral radiographs in natural head position (NHP) were taken from each subject, one before and the other one after neuromuscular deprogramming. The average usage period of the occlusal splint was 6 months and 7 days. Craniocervical cephalometric analysis was carried out by evaluating the craniovertical (SN/VER), craniocervical (OPT/SN and CVT/SN), and cervicohorizontal (OPT/HOR and CVT/HOR) angles, as well as the angle of the cervical curve (OPT/CVT). No significant changes were seen in the control group. It was concluded that there was a significant extension of the head, both in relation to the true vertical line, as demonstrated by the increase of the SN/VER angle, and to the cervical column, as demonstrated by the increase of the CVT/SN angle. Likewise, the cervical column showed significant backward inclination in relation to the true horizontal line, as demonstrated by increase of the CVT/HOR angle. No significant alteration of the cervical curve was observed. In addition, significant correlation coefficients were observed between the differences of the pre- and post-deprogramming values of the measurements the measurements SN/VER and OPT/HOR, SN/VER and CVT/HOR, SN/VER and CVT/SN, OPT/CVT and OPT/HOR, OPT/CVT and OPT/SN, OPT/HOR and CVT/HOR, OPT/HOR and OPT/SN, and OPT/SN and CVT/SN.