Invisalign System as a Treatment of a Skeletal Open Bite: A Case Report With a 5-Year Follow-up

Background: Orthodontic treatments of skeletal open bite are among the most challenging and at high relapse. Available therapies vary from behaviour-modifying appliances in growing patients to surgical approach in adults. Recently, clear aligners, such as Invisalign®, have also been proposed as a treatment modality, to be used alone or in combination with temporary anchorage devices. Case report: A 19-year-old female presented with 3-mm anterior open bite, peg-shaped upper lateral incisors, incorrect tongue posture at rest and during function. Due to aesthetic request, an orthodontic camouflage with Invisalign® was carried out for 17½ months, along with myofunctional therapy and composite veneers on upper lateral incisors. During the first months of retention, intermaxillary vertical elastics were maintained at night-time as positive feedback to the tongue. A 5-year follow-up confirmed stability of the results. Conclusions: A system of clear aligners in combination with myofunctional therapy was effective in the treatment of a skeletal open bite malocclusion, with stability at 5 years. The closure of the anterior open bite was obtained through a combination of lower molar intrusion, incisor extrusion and counterclockwise rotation of the mandible. In selected cases of optimal compliance, Invisalign® may constitute a feasible treatment option in management of open bite in non-growing patients.

Root resorption associated with maxillary buccal segment intrusion using variable force magnitudes: A randomized clinical trial

ABSTRACT Objectives To compare the root resorption resulting from miniscrew-supported maxillary posterior dentoalveolar intrusion using two different force magnitudes. Materials and Methods: Adult patients with skeletal open bite, indicated for maxillary posterior dentoalveolar intrusion, were recruited and randomly assigned to the comparison or intervention groups. The comparison group involved applying 200 g of intrusive force per segment, which measured 20 g per root, while this force was 400 g per segment in the intervention group, measuring 40 g per root. Results Twenty participants were included in the final analysis after 2 patients dropped out, 1 in each group, to end up with 10 subjects (200 roots) per group. There was statistically significant root resorption of 0.84 ± 0.96 mm and 0.93 ± 1.00 mm in the comparison and the intervention groups, respectively. However, there was no statistically significant difference between the groups. Conclusions Root resorption inevitably took place in association with orthodontic intrusion. However, increasing the magnitude of the intrusive force did not increase the amount of root resorption, either statistically or clinically.

Assessment of the duration of the pubertal growth spurt in patients with skeletal open bite

Purposes The objectives were to assess the skeletal age of patients with skeletal open bite and to estimate and compare the mean chronological age related to CS3 and CS4 (cervical stage, CS) and the duration of the pubertal growth spurt (PGS). Methods Orthodontic records of 145 patients were analyzed in this retrospective cross-sectional study. The study group comprised 104 patients with skeletal open bite (angle between cranial base plane line [NS] and mandible base plane line [ML] > 39° according to Steiner), whereas the control group comprised 41 patients with normal anteroposterior and vertical measurements. Skeletal age was assessed using the 6‑stage CVM (cervical vertebral maturation) method according to Baccetti. Quantitative variables were characterized by means of the arithmetic mean and standard deviation. The PGS duration was calculated as the difference between the means of the chronological ages related to CS3 and CS4. Results In the study group, the arithmetic means related to CS3 and CS4 were 11.12 and 13.54 years, respectively; the duration of the PGS was 2.42 years. In the control group, the arithmetic means related to CS3 and CS4 were 10.71 and 11.82 years, respectively; the duration of the PGS was 1.11 years. Conclusions In patients with skeletal open bite, the duration of PGS is longer but it occurs at a similar chronological age compared to patients with normal anteroposterior and vertical measurements. The PGS in males begins later than in females. Knowledge on the longer growth spurt in patients with skeletal open bite compared to patients with normal anteroposterior and vertical relationships can be useful in the selection of an appropriate therapeutic method and also provides information about the possibility of a longer and thus more effective orthopedic approach directed at positive change in the vertical growth pattern during intense bone remodeling.