Relationships between vertical facial pattern and natural head position,cervical posture in patients with skeletal class Ⅰ relationship / 吉林大学学报(医学版)

Objective To investigate the natural head position and cervical posture in the patients with different vertical facial patterns with skeletal class Ⅰ relationship,and to clarify the relationships between vertical facial patterns and natural head position, cervical posture in the patients with skeletal class Ⅰ relationship. Methods 94 patients aged 8- 15 years old with skeletal class Ⅰ relationship were selected as the subjects.The subjects were classified into high angle group,average angle group,and low angle group according to their mandibular plane angles.The cephalometric radiographs in natural head position were taken,and the variables representing craniofacial morphology,head position,and craniocervical posture were measured.The intergroup differences in variables were compared.Results The inclinations of mandible to the true vertical and cervical column (ML/VER,ML/OPT,ML/CVT)were smallest in high angle group,and they were largest in low angle group (P 0.05). Conclusion The significant differences exist in natural head position and cervical posture among the patients with skeletal class Ⅰ relationship with different vertical facial patterns (high angle,average angle,low angle);the subjects with high angle show extended head position and cervical posture,while the subjects with low angle exhibit the opposite tendency.

The effects of maxillary protraction appliance (MPA) depending on vertical facial patterns / 대한치과교정학회지

Preadolescent children with deficient maxillae are suitable candidates for the maxillary protraction appliance(MPA). The theoretical effect of the MPA is protraction or anterior displacement of the maxilla. However, it is known that complex effects such as anterior displacement of the maxillary teeth, downward and backward rotation of the mandible, linguoversion of the mandibular anterior incisors, are known to play a role in improving the Cl III malocclusion. There have been much studies with regard to maxillary protraction, but the different effects of MPAs depending on the vertical facial pattern are not known precisely. This study was based on 67 patients (31 males, 36 females) aged from 6 years 6 months to 13 years 3months, who visited the Dept. of Orthodontics at Yonsei Univ., Dental Hospital and diagnosed as skeletal Class III with maxillary deficiency. They were divided into 3 groups (low, average, high angle groups) depending on gonial angle and the SNMP (Go-Gn) angle, respectively. Pretreatment and post-treatment lateral cephalograms were used to compare the effects of MPA and the following conclusions were obtained: 1) A significantly large amount of backward movement of the B point was observed in patients with a low SNMP angle. Those with a high SNMP angle had significant forward movement at A point. 2) The patients with low gonial angle had the least forward movement at the A point, and those with a high angle had more forward movement. 3) In comparing the arcTan of the A point, the high angle group showed more horizontal movement while the low angle group showed more vertical movement. 4) There was no significance between the treatment duration of the SNMP and the Gonial angle groups.

Avaliação cefalométrico-radiográfica da morfologia mandibular nas más oclusões de classe I e de classe II 1a. divisão e nos padrões faciais braqui, meso e dolicocéfalo / Cephalometric evaluation of mandibular morphology in class I and class II division 1 malocclusions and in brachy, meso and dolichofacial patterns

A morfologia mandibular de crianças brasileiras, leucodermas, na faixa etária de 7 a 10 anos, foi avaliada por meio do método cefalométrico em 125 telerradiografias laterais. A amostra foi dividida de acordo com a má oclusão - Classe I (C1) ou Classe II 1ª divisão (C2) - e com o padrão facial - braquicéfalo (B), mesocéfalo (M) ou dolicocéfalo (D). Os cefalogramas foram compostos por variáveis angulares, que dimensionaram, na mandíbula, o ângulo goniano (AG), a inclinação do plano oclusal (PO), a inclinação da sínfise (IS) e as inclinações do incisivo (I1) e do primeiro molar (I6); e por variáveis lineares, que dimensionaram o comprimento total (CT), o comprimento do corpo (CC), a altura do ramo (AR) e as alturas do incisivo (A1) e do primeiro molar (A6). A análise estatística foi realizada com a aplicação de testes não paramétricos. Quando a amostra foi agrupada segundo a má oclusão, evidenciou-se que a mandíbula na C2 apresentou menores CT, CC e A6 e maior I6 que na C1. Quando a amostra foi agrupada segundo o padrão facial, observou-se que: a) B apresentou AG e PO menores que M e D; A1 e A6 menores que D; I1, I6, CT e AR maiores que M e D; CT e CC maiores que M; b) M apresentou AG, PO e A1 menores que D; I6 e AR maiores que D

The mandibular morphology of white Brazilian children, between 7 to 10 years old, was evaluated by computerized cephalometric method in 125 lateral radiographs. The sample was divided according to the malocclusio - Class I (C1) or Class II division 1 (C2) - and to the facial pattern - brachyfacial (B), mesofacial (M) or dolichofacial (D). The cephalograms were composed by angular variables, which established the size of the gonial angle (GA), the occlusal plane inclination (OP), the symphysis inclination (SI), and first molar (I6) inclination; and by linear variables, which established the mandible size (MS), the corpus length (CL), the ramus height (RH), as well as the incisor (H1) and first molar (H6) height. The statistical analysis was carried out with the application of non parametric tests. When the sample was grouped according to the malocclusion, it was noticed that the mandible at C2 presented smaller MS, CL and H6 and greater I6 than at C1. When the sample was grouped according to the facial patterns, it was noticied that: a) B presented GA and OP smaller than M and D; H1 and H6 smaller than D; I1, I6, MS and CL greater than M and D; MS and CL greater than M; b) M presented GA, OP and H1smaller than D, I6 and RH greater than D