Tooth displacement in shortened dental arches: a three-dimensional finite element study.

STATEMENT OF PROBLEM: Some patients may opt for a prosthetic rehabilitation without replacing all missing teeth, finishing treatment with a reduced dental arch. This choice may be due to biologic reasons or financial restrictions. It is unclear if a reduced dental arch functions as well as a complete dental arch. PURPOSE: The purpose of this study was to analyze whether shortened dental arches could result in tooth displacement. MATERIAL AND METHODS: Four different 3-dimensional maxillary and mandibular arches with different levels of arch length reduction were created. In all models, anatomic structures that represent the temporomandibular joint, cortical and cancellous bone, enamel, dentin, and periodontal ligament were modeled. Mechanical properties were attributed to each anatomic component, and a total occlusal load of 100 N on masseter, temporal, and medial pterygoid muscles was simulated for each model. The MSC. Patran software was used for the preprocessing and postprocessing of the biomechanical analysis of the models. One complete dental arch was used as the control. RESULTS: The simulations showed that shortened dental arches presented greater tooth displacements than those found in a complete dental arch. The changes in mandibular tooth position were greater than those observed in the maxillary arches. In finite element models 1 and 2, the largest maxillary displacements were found for posterior teeth. CONCLUSIONS: Decreasing numbers of occlusal units resulted in increasing amounts of displacements of the remaining teeth, which may compromise dental stability in patients with shortened dental arches.

Interdisciplinary treatment of a class III patient with congenitally absent maxillary lateral incisors.

UNLABELLED: The purpose of this paper is to present a case report of an adult Class III patient presenting bilateral congenitally missing maxillary lateral incisors that compromised occlusal function as well as smile and facial esthetics. After the interdisciplinary diagnosis, spaces for prosthetic substitution were opened with the help of miniscrews. The orthodontic therapy achieved a better dental relationship, and the final interdisciplinary treatment results represented a significant improvement in function and both dental and facial esthetics. CLINICAL SIGNIFICANCE: The interdisciplinary treatment of orthodontics and restorative dentistry is very important because the two complement each other in search of the best for the patient. This case demonstrates very well that where orthodontics provided the best tooth position prior to implant placement and restorations.

Selective alveolar corticotomy to intrude overerupted molars.

Orthodontic intrusion of overerupted molars in adults is challenging for most clinicians. Efficient intrusion can be achieved by combining selective alveolar corticotomies with a modified full-coverage maxillary splint to reduce surgical risks, treatment time, and costs for both orthodontists and patients.

Long-term Stability of a Camouflage Retreatment of an Asymmetric Class III/Posterior Open Bite Using Sliding Jigs.

This article reports the camouflage retreatment of an adult patient presenting an asymmetric Class III malocclusion and posterior open bite. Sliding jigs (SJs) associated with intermaxillary elastics were used. The long-term stability of the excellent results suggests that the use of SJs to correct asymmetric posterior occlusions may be effective.