Three-dimensional analysis of the distal movement of maxillary 1st molars in patients fitted with mini-implant-aided trans-palatal arches / 대한치과교정학회지

OBJECTIVE: The aim of this study was to investigate three-dimensional molar displacement after distalization via miniscrews and a horizontal modification of the trans-palatal-arch (TPA). METHODS: The subjects in this clinical trial were 26 Class II patients. After the preparation of a complete set of diagnostic records, miniscrews were inserted between the maxillary 2nd premolar and 1st molar on the palatal side. Elastic modules connected to the TPA exerting an average force of 150-200 g/side parallel to the occlusal plane were applied. Cone-beam computed tomography was utilized to evaluate the position of the miniscrews relative to the adjacent teeth and maxillary sinus, and the direction of force relative to molar furcation. The distances from the central point of the incisive papilla to the mesiopalatal cusps of the 1st maxillary molars and the distances between the mesiopalatal cusps of the left and right molars were measured to evaluate displacement of the maxillary molars on the horizontal plane. Interocclusal space was used to evaluate vertical changes. RESULTS: Mean maxillary 1st molar distalization was 2.3 +/- 1.1 mm, at a rate of 0.4 +/- 0.2 mm/month, and rotation was not significant. Intermolar width increased by 2.9 +/- 1.8 mm. Molars were intruded relative to the neighboring teeth, from 0.1 to 0.8 mm. CONCLUSIONS: Distalization of molars was possible without extrusion, using the appliance investigated. The intrusive component of force reduced the rate of distal movement.

Evaluation of dentoskeletal changes and facial harmony in treated children with Skeletal Class 2

There are several studies to evaluate dento-skeletal changes after treatment of skeletal class 2 malocclusion with Dr Farmand's functional appliance but in non of them facial harmony has been considered. The purpose of the present study is evaluation of facial harmony in addition to dentoskeletal changes after treatment with Dr Farmand's functional appliance. Initial and final cephalograms of eighteen treated skeletal class 2 div 1 patients have been selected. All of them had been treated with Farmand's appliance before termination of growth spurt. Each cephalogram was separately traced two times. Means of before and after treatment data were compared with paired t-test. Skeletal class 2 relationship has been successfully corrected through decreasing ANB angle [-1.88 +/- 1.75,p=0.00], 66 and angle of convexity [-1.47 +/- 1.21, p=0.00], and Also dental changes [upper incisor retrusion and lower incisor protrusion] were occurred [decrease of U1 to SN was -4.77 +/- 4.71, p=0.00 and increase in IMPA was +3.93 +/- 2.87,p=0.00]. Soft tissue changes involved retrusion of upper lip to E-line [-2.86 +/- 1.88,p=0.00] and decrease of upper sulcus dept [-1.55 +/- 2.04, p=0.005] and lower sulcus dept [-2.44 +/- 1.85,p=0.00] which played an important role in improvement of facial harmony. Lower lip was placed more anteriorly relative to H-line [1.37 +/- 1.48 p=0.001] which is not desirable in profile harmony. Dr Farmand's functional appliance is effective in treating skeletal class 2 patients by producing skeletal as well as dental improvement. Soft tissue harmony also is improved but final position of lower lip must be regarded more carefully

Correction of crowding by Soft Elastic Foils: a case-report study

Everyday because of developing new materials and techniques,more adults become interested in orthodontic treatments. Soft positioner and its new generation in the name of Invisalign System is an example. The present case report was designed to study the effects of soft elastic foils as serial aligners on treating the mild to moderate crowding. Three teenage patients with crowding not more than 6 millimeters were selected. After the preparation of orthodontic diagnostic records and filling the periodontal chart, manual teeth setup was carried out on working casts with a maximum 0.5 millimeter displacement. Aligners were made up of bioplast foils. The appliance was worn by patient full time for at least 2 weeks. Then the new one was made and this procedure was continued until complete tooth alignment. The last aligner was used as retainer for three months later These variables were evaluated after treatment: dental alignment, over jet, overbite, inclination of upper and lower incisors, lips relation to E line, mandibular plan angle, clicking in TMJ, periodontal status and tooth pain. Active treatment period lasted between 3-5 months. Anterior crowding was completely corrected in all patients. Protrusion of upper and lower incisors were seen in lateral cephalograms. Overbite, mandibular plan angle and lips relation to E line did not change. Improvement of periodontal status were recorded in all patients.Low to moderate toothache was reported during the first 2 days. Mild to moderate crowding could be corrected successfully with soft elastic foils [Serial Aligners] without deleterious effects on TMJ and periodontium however manual tooth setup was time consuming