Dolichofacial Type Research Articles

Padrão facial na dentadura decídua: estudo epidemiológico

INTRODUÇÃO: é possível definir a morfologia facial e o padrão de crescimento em idade precoce, a partir da dentadura decídua completa. OBJETIVOS: frente à escassez de trabalhos na literatura pertinente ao assunto, a presente pesquisa explora o diagnóstico epidemiológico da face no estágio de dentadura decídua. METODOLOGIA: a amostra foi composta por 2.009 crianças de etnia brasileira, de ambos os gêneros, entre 3 e 6 anos de idade, no período de dentadura decídua completa, de 20 pré-escolas do município de Bauru/SP. RESULTADOS E CONCLUSÕES: baseando-se nos resultados obtidos no levantamento epidemiológico, foi encontrado - na análise em norma lateral - predomínio de crianças Padrão I (63,22%) em relação ao Padrão II (33,10%) e Padrão III (3,68%), não havendo diferenças estatisticamente significativas quanto ao gênero. Na análise em norma frontal, houve predomínio do tipo mesofacial (64,56%) em relação ao dolicofacial (21,90%) e braquifacial (13,54%), sendo que a proporção do tipo braquifacial nas meninas foi significativamente superior em relação aos meninos. Na distribuição dos tipos faciais frontais dentro dos padrões faciais sagitais ficou evidenciada uma manifestação mais freqüente do tipo dolicofacial dentro dos Padrões II e III, sendo encontrado dimorfismo quanto ao gênero, notadamente no Padrão I, onde houve maior manifestação do tipo braquifacial e menor manifestação do dolicofacial no gênero feminino.

A morphological study of the relationship between arch dimensions and craniofacial structures in adolescents with Class II Division 1 malocclusions and various facial types

The objective of this study was to evaluate dental arch forms associated with various facial types in adolescents with Class II Division 1 malocclusions by using mathematical functions to describe the arch form at clinical bracket points. Pretreatment lateral cephalograms and dental study casts of 73 white Brazilians were divided into 3 groups according to facial type: 17 brachyfacial, 24 mesofacial, and 32 dolichofacial. Fifteen landmarks on each dental cast were digitized. Computer-generated mathematical arch forms (fourth-degree polynomial equation and beta function) were used to evaluate arch form differences by superimposition. The constant term related to dental arch depth of the brachyfacial subjects was significantly greater than that of the mesofacial subjects in the maxillary arch (P = .004). Superimposition of maxillary arch analysis showed that the posterior segment width of the mathematically computed arch form tended to increase from dolichofacial type to brachyfacial type. The arch forms drawn by the 2 equations coincided at the incisal and molar regions. The beta function is appropriate for predicting the finishing arch form, and the polynomial equation is appropriate for the analysis (diagnosis) of various Class II malocclusions, including ovoid, tapered, and square arch forms and dental arch asymmetry.

Surgical Maxillofacial Treatment of Obstructive Sleep Apnea

Obstructive sleep apnea is the most common sleep-related breathing disorder, with a surprisingly high prevalence. The treatment of choice is nasal continuous positive airway pressure (CPAP) ventilation during sleep, which has to be applied throughout the patient's whole life. Because of various underlying pathomechanisms in patients with certain craniofacial disorders--narrow posterior airway space and maxillary-mandibular deficiency--surgical therapy by craniofacial osteotomies seems possible. A series of 38 consecutive patients were treated by 10-mm maxillomandibular advancement by retromolar sagittal split osteotomy and Le Fort I osteotomy, respectively. Obstructive sleep apnea syndrome was improved considerably in all patients; there was no significant difference compared to the results under nasal CPAP. In 37 of 38 patients, the postoperative apnea-hypopnea index was reduced clearly to under 10 per hour, oxygen saturation rose, and sleep quality improved. This was achieved by maxillomandibular advancement of 10 mm without secondary refinements in all but 2 patients. In one patient, the apnea-hypopnea index could only be reduced to 20 per hour, probably because of insufficient maxillary advancement. These results indicate that successful surgical treatment is possible in a high percentage of selected patients with certain craniofacial characteristics. In addition to cardiorespiratory polysomnography, there should be routine cephalometric evaluation of all patients. Maxillomandibular advancement should be offered as an alternative therapy to all patients with maxillary and/or mandibular deficiency or dolichofacial type in combination with narrow posterior airway space.

Surgical treatment of obstructive sleep apnea by maxillomandibular advancement.

In recent years obstructive sleep apnea syndrome has gained increasing interest. Treatment of choice is nasal continuous positive airway pressure ventilation during sleep for upper airway patency, which does not cure sleep apnea and has to be applied throughout a patient's lifetime. In respect to various underlying pathomechanisms, in certain cases with craniofacial disorders, causal therapy by craniofacial osteotomies seems possible. A series of 21 consecutive patients with maxillary and mandibular deficiency were treated primarily with a 10-mm maxillomandibular advancement by retromolar sagittal split osteotomy and Le Fort-I osteotomy, respectively. Obstructive sleep apnea syndrome was considerably improved in all patients. In 20 of 21 patients, the postoperative respiratory disturbance index (RDI) was reduced clearly to under 10, oxygen saturation rose and sleep quality improved. This was achieved by a maxillomandibular advancement of 10 mm without secondary refinements. In one patient the RDI could only be reduced to 20, probably due to insufficient maxillary advancement; oxygen desaturations still existed despite secondary corrections. These results indicate that successful surgical treatment is possible in a high percentage of selected patients with certain craniofacial characteristics. In addition to cardiorespiratory polysomnography there should be routine cephalometric evaluation of all patients. Maxillomandibular advancement should be offered as an alternative therapy to all patients with maxillary and/or mandibular deficiency or dolichofacial type in combination with narrow posterior airway space.

The comparison of influence of difficulties in nasal breathing on dentition between different facial types

It is commonly assumed that nasorespiratory function can exert a dramatic effect upon the development of the dentofacial complex. Specially, it has been stated that chronic nasal obstruction leads to mouth breathing, which causes altered tongue and mandibular positions. If this occurs during a period of active growth, the outcome is development of the facies. Such patients characteristically manifest a vertically long lower third facial height, narrow alar bases, lip incompetence, a long and narrow maxillary arch and a greater than normal mandibular plane angle. But several authors have reported that so-called adenoid facies is not always associated with adenoids and mouth breathing, and that a particular type of dentition is not always found in mouth breathers with or without adenoids. Some authors have believed adenoids lead to mouth breathing in cases with particular facial characteristics and types of dentition. We assumed that the ability to adapt to individual's neuromuscular complex is various. So, we compared the difference of influence of mouth breathing between childrens who have different facial types. This study included 60 patients and they were divided into three groups by Rickett's facial type. Their dentition and tongue position were compared. The results are as follows. 1. There is a significant difference in arch width of upper molars between different facial types. Especially dolichofacial type patients have narrowest arch width. 2. There is a significant difference in tongue position between different facial types. Especially dolichofacial type patients have lowest positioned tongue.

The Begg light wire technique and dentofacial development.

The purpose of this paper is to demonstrate the application of the Begg technique in achieving specific treatment objectives in relation to facial type. Emphasis is placed on both the control of incisor position and the vertical position of the mandible. In order to meet these objectives the site of extractions can be varied, as well as components of the Begg system, such as the use of intermaxillary elastics and arch wire modification. In brachyfacial types with forward mandibular growth rotation, treatment objectives may include incisor intrusion and backwards rotation of the mandible using a non-extraction technique. In contrast, in dolichofacial types with forward mandibular growth rotation, intrusion of incisors and a stable vertical mandibular position may be the primary treatment objectives. In these cases extraction of the four first premolars is usually necessary. The objective is a final tooth position which is in harmony with the facial profile, and compatible with subsequent occlusal maturation.

The Begg light wire technique and dentofacial development

The purpose of this paper is to demonstrate the application of the Begg technique in achieving specific treatment objectives in relation to facial type. Emphasis is placed on both the control of incisor position and the vertical position of the mandible. In order to meet these objectives the site of extractions can be varied, as well as components of the Begg system, such as the use of intermaxillary elastics and arch wire modification. In brachyfacial types with forward mandibular growth rotation, treatment objectives may include incisor intrusion and backwards rotation of the mandible using a non-extraction technique. In contrast, in dolichofacial types with forward mandibular growth rotation, intrusion of incisors and a stable vertical mandibular position may be the primary treatment objectives. In these cases extraction of the four first premolars is usually necessary. The objective is a final tooth position which is in harmony with the facial profile, and compatible with subsequent occlusal maturation.

Activator headgear therapy

A method of treatment is described using an activator and cervical headgear simultaneously to correct malocclusions of the Class II, Division 1 type. The case reports of ten treated patients are used to demonstrate the effects of the application of this technique. Changes in the dentition and facial skeleton were analyzed and the significance of the different responses to the application of the same appliances assessed. The hypothesis proposing that a simultaneous application of both appliances may result in a number of desirable effects greater than that induced by each individual appliance is examined. The hypothetical basis for the application of this technique is partially substantiated by the clinical observations. Within a period of about 1 year, correction of the Class II molar occlusion to a Class I molar occlusion is obtained, with a simultaneous reduction of overbite and overjet. Skeletal changes were found to be variable and related to facial type and the rate of facial growth. Brachyfacial and mesofacial types responded most favorably to treatment. The most favorable effects were observed when there was a large quantitative mandibular growth and brachyfacial or mesofacial growth pattern. In dolichofacial types with a slow mandibular growth rate, mandibular rotation was found to be clockwise; cervical traction appears contraindicated, and a combination of activator with occipital medium to high pull is considered more appropriate.