Despite having a correct anterior occlusal relationship between upper and lower teeth with canines in perfect Class I, some patients have imperfect posterior occlusal relationships with first molars in positions that are slightly Class II or Class III owing to an arch length discre pancy in the upper and lower buccal segments.

From this study of 62 subjects treated with full banded appliances and no bicuspid extrac tions we were able to determine the ideal relationship of the widths of the lower bicuspid and molar teeth with their upper antagonists, one that make it possible for the attainment of Class I relationships of both canines and first molars. This ideal value is 1.062.

We discuss the therapeutic implications of this finding, notably its influence on extraction decisions and propose solutions for cases of frank disharmony.

Uncovering the Herbst rods can make wearing the appliance more comfortable for some patients. On the other hand there can be some disadvantages to this procedure:

- it might make cementing or bonding of the appliance, in case of poor cooperation, impossible;

- it might interfere with vertical growth depending on the bearing points;

- it might disturb occlusion because of the wires that would pass over the occlusal surfaces;

- it might impair the retention of the appliance during the period when temporary teeth are being shed.

This article will also present other modifications, relating to the pivots, to the elimination of the anterior portion of the device, and to the use of springs on the branches. Their respective benefits and limitations will also be presented and discussed.

The aim of this study was to observe the effects of treatment with a Trainer T4K® myofunc tional appliance of thirteen late mixed dentition patients. We conducted thorough clinical examinations that included assessment of breathing and swallowing capabilities and took profile cephalograms and study models for each one. We also selected a control group that had been treated only with palatal expansion so that we could distinguish the effects of myofunctional therapy from those of expansion. We observed significant mandibular growth (p<0.05) of 3.24 mm on the average and a significant decrease in overjet, essentially linked to dento-alveolar effects, in the Trainer T4K® group. Swallowing and breathing function also improved in these patients. The two groups had similar maxillary and mandibular expansion.

So we conclude that use of a Trainer T4K® myofunctional appliance results in improved antero-postero dental relationships and an improvement in oral functioning.

Introduction: The biteplate facebow includes a metallic occlusal plate that rests between the upper and lower incisors that is designed to correct the incisal overbite. The objective of this study is to evaluate the skeletal and dental effects of this appliance.

Patients and method: We chose thirty patients, sixteen boys and 14 girls, who had Class II malocclusions associated with a deep anterior overbite for this study. None of them had had teeth extracted as an adjunct to therapy. The only orthodontic appliance they wore was the facebow biteplate, for fourteen hours a day on the average, until their Class II molar relationship was corrected.

Results: After correction of the Class II molar relationship, we observed statistically significant before and after differences for both the incisal deep bite and the labial inclinations of the maxillary and mandibular incisors. We also noted skeletal changes at the close of treatment, notably of the mandibular plane and of point A, but they were not significant.

Conclusion: With this appliance, Class II Angle malocclusions with deep anterior overbites can be treated in a single stage, essentially by movements of teeth.

Introduction: Spina bifida is a rare congenital disorder due to a closure anomaly of the neural tube.

Clinical case: A 9 years-old girl presents with lumbar spina bifida aperta and cervical spina bifida occulta. Her case illustrates the importance of orthodontic xrays in the diagnosis of cervical spine malformations.

Discussion: There are two categories of spina bifida. When refered to as aperta, the disorder associates a dorsal vertebral bony gap and an involvement of the spinal cord. A skin pouch can form and include meninges alone (meningocele) or meninges with spinal cord (myelomeningocele). Spina bifida is generally located in the lumbar or sacral regions, and extends over 2-3 vertebrae. On the other hand, the involvement of the cervical spine is often of the occulta type, where the defect is covered by skin and is limited to the bone. This rare condition cannot be ignored by the clinician as the craniocervical junction anomalies induced by this malformation can be associated with C1-C2 instability, as in our case report.

Angle corrected anterior crowding by advancing the crowns of the incisors. For a long time he hoped the apices would follow along spontaneously. Then because of the uncertainty of this reaction, he started his quest for an appliance that would be able to accomplish root movement. The first one was difficult for orthodontists to manipulate, the second did not incorporate vertical control, but the third had all the qualities Angle was looking for. He died satisfied.