Objective treatment outcome assessment of a completely customized lingual appliance: A retrospective study.

OBJECTIVE: To assess the outcome quality of subjects treated with a completely customized lingual appliance (CCLA) in a postgraduate university program, using the ABO Objective Grading System (OGS), by testing the null-hypothesis of a significant proportion of post-treatment cases exceeding an adjusted 'exam failure' threshold value of OGS=24. MATERIALS AND METHODS: This retrospective single-arm study included 66 consecutively debonded CCLA cases (m/f 19/47; mean age: 25.1±9 years) treated at Hannover Medical School (MHH, Hannover, Germany). The discrepancy index (DI) was assessed on initial plaster casts. The OGS of the cast-radiograph evaluation was scored for both set-up and post-treatment casts, including the seven components of alignment/rotation, marginal ridges, buccolingual inclination, overjet, occlusal contacts, occlusal relationships and interproximal contacts, to parameterize differences between those. RESULTS: DI score distribution (≥20, <20) was 25 (37.9%)/41 (62.1%) subjects. Mean initial DI was 17.3±8.5. Mean set-up OGS was 10.4±4.4 (min-max: 3-21), mean final OGS was 17.7±5.9 (min-max: 7-33), and the difference 7.3 (post-treatment - set-up) was statistically significant (p<0.0001; 95% CI [5.8, 8.7]). The null-hypothesis was rejected: A statistically significant proportion of the final casts (n=58; 87.8%) scored below OGS=24 by exact binomial test (P<0.0001; 95% CI [77.5%, 94.6%]). The rate of a final OGS score<24 was not significantly different (P=0.98) between both DI (≥20, <20) groups. CONCLUSIONS: The outcome quality of the CCLA treatment in this postgraduate university setting was high and therefore sufficient for a vast majority of treated cases to pass the ABO-OGS clinical examination.

Controlling incisor torque with completely customized lingual appliances.

PURPOSE: To test the null hypothesis of no significant deviation between the center of rotation (CROT) and the center of resistance (CRES) during space closure in Angle class II division 2 subjects achieved using a completely customized lingual appliance (CCLA) in combination with class II elastics and elastic chains. METHODS: This retrospective study included 29 patients (male/female 11/18; mean age 15.6 [13-27] years) with inclusion criteria of an Angle class II/2 occlusion of least of half of a cusp, maxillary dental arch spacing, completed CCLA treatment (WIN, DW Lingual Systems, Bad Essen, Germany) in one center with a standardized archwire sequence and use of class II elastics and elastic chains only. Maxillary incisor root inclination was assessed by X­ray superimpositions of the maxilla at the beginning (T1) and the end (T3) of CCLA treatment. Using Keynote software (Apple®, Cupertino, CA, USA), the incisor's CROT was assessed with the point of intersection of the incisor axes (T1; T3) following vertical correction of overbite changes. CRES was defined at 36% of the incisor's apex-incisal edge distance. RESULTS: The null hypothesis was rejected: the mean CROT - CRES difference was 52.6% (p < 0.001). The mean CROT was located at 88.6% (min-max 51-100%) of the incisor's apex-incisal edge distance. Although 6.9% of CROT were located between the CRES and the alveolar crest, the vast majority (93.1%) were assessed between the alveolar crest and the incisal edge, or beyond. CONCLUSION: CCLAs can create upper incisor palatal root torque even in cases in which lingually oriented forces applied incisally to the center of resistance of the upper incisors counteract these intended root movements.

[Morphological and functional peri-oral changes during early treatment of Class II division 1 malocclusions using EF Line ® functional education devices]. / Modifications péri-orales fonctionnelles et morphologiques lors du traitement précoce des malocclusions de classe II division 1 avec des appareils d'éducation fonctionnelle de la gamme EF Line®.

INTRODUCTION: The aim of this article was to assess the impact of a flexible functional education splint for interceptive treatment of Class II division 1 dysmorphoses. MATERIALS AND METHODS: An observational, prospective, multi-center non-comparative EGIDYS study was conducted in 81 children with a Class II division 1 malocclusion presenting one or several functional disorders. Patients wore a flexible splint in the EF Line® range for a minimum of two hours per day and all night over 12 months in combination with educational exercises depending on the case. Patients were followed at one month, four months and twelve months of treatment. Ventilation, lingual position, labial peri-oral muscle tension, arch forms and dentoskeletal cephalometric measurements were assessed at initiation and completion of the functional education. RESULTS: Functional examination on inclusion showed that the majority of children displayed a low tongue position at rest, oral or mixed ventilation, abnormal labial and peri-oral muscle tone and, in many cases, a narrow maxilla. Initial cephalometric examination recorded the following parameters: overjet, deep bite, and inclination of the lower incisors relative to the A-Pog line, and the SNA, SNB and ANB angles. After twelve months of functional education with a flexible EF Line® splint, improvement was observed in the orofacial functions as shown by correction of the tongue position at rest as well as the lingual index indicating the position of the tongue against the palate, reduced tension of both the lower lip and the buccinator muscles at rest and in function, increased nasal breathing ability and a more rounded maxillary arch form. In addition, a major reduction in overjet and deep bite were visible as well as a significant reduction of the ANB angle due to its increased SNB component. This first stage in the orthodontic treatment plan resulted in a 73% improvement of Class II division 1 malformations. Correction of the malocclusion and functional disorders correlates significantly with compliant wearing of the EF Line® splints. CONCLUSIONS: This study demonstrates that the design of EF Line® flexible functional education devices effectively corrects functional disorders linked to poor tongue position and triggers positive dentoskeletal changes, as compared with no treatment. From the clinical viewpoint, flexible EF Line® splints can contribute to orthopedic and orthodontic treatment of Class II division 1 malformations.

[Completely-customized lingual orthodontics to correct class II malocclusion in adolescents]. / La correction de la classe II chez les adolescents à l'aide de l'orthodontie linguale totalement individualisée.

INTRODUCTION: Completely-customized lingual orthodontics is an efficient, predictable and esthetic solution for our patients. Adolescents showing a class II malocclusion represent the majority of patients in orthodontic practices. Several modes of treatment are available to correct this sagittal discrepancy such as inter-maxillary elastics, flexible or rigid protrusion devices, maxillary distalization using mini-screws or symmetric and asymmetric extractions. The choice depends on several decision criteria such as the severity of the malocclusion, the symmetry of the class II discrepancy as well as the age and the motivation of the patient. MATERIALS AND METHODS: In this article, the authors will describe the current therapeutical strategies to correct a class II malocclusion in adolescents with a completely-customized lingual appliance. CONCLUSION: It is as easy to correct a significant class II malocclusion with a lingual technique as it is with vestibular techniques, completely-customized lingual orthodontics providing the advantage of facilitating treatments.

[Targeting the smile: why don't we aim at the lips?] / Objectif sourire : et si l'on s'intéressait aux lèvres ?

INTRODUCTION: The smile is more than a question of well-aligned teeth. Harmonization of the dentition with the soft tissues is the key to a beautiful smile. This abundantly illustrated article looks more closely therefore at the lips and their movements. MATERIALS AND METHODS: The article begins by explicating the terminology relevant to the lips, then addresses the notions of volume, mobility and aging, and concludes by examining the orthodontic clinical dimension. DISCUSSION: Practitioners must be fully informed when assessing requests for treatment formulated by adult patients and a detailed analysis must be made of the lips at rest and during functioning. Harmony of both the teeth and the soft tissues is indispensable to a beautiful smile. A multidisciplinary approach is often necessary. CONCLUSION: Restoring the patient's smile therefore obliges the practitioner to think beyond mere problems of dental occlusion.