Orthodontic treatments with optically transparent aligners have seen a constant increase in acceptance in recent years. The low acceptance rates of conventional orthodontic devices in adult populations, due to a perceived lack of attractiveness, as well as workflows becoming easier for practitioners, can explain the rising demand for aligner treatments.^1,2 Orthodontic tooth movement is accomplished by employing prolonged pressure on that tooth. The initial movement is rapid, as it occurs within the dental alveolus. The periodontal ligament (PDL), which connects the tooth to the alveolar bone, is stretched on one side and compressed on the other side of the root so that a tension and a compression side can be differentiated.³ The disruption of the mechanical balance of PDL and bone leads to the recruitment of osteoclasts and osteoblasts in the vicinity of the tooth.⁴ These specialized cells are responsible for bone resorption on the compression side and bone apposition on the tension side, respectively.⁵ This bone remodeling usually occurs within 40 days after the initial force is applied.³

Dielectric elastomer transducers (DETs) are smart devices as they can operate as a sensor, an actuator, an electric energy harvester, and a self-sensing actuator.¹ 2. 3. ^{– 4} State-of-the-art DETs are based on elastomer membranes with micrometer thickness and are often fabricated by spin-coating, doctor-blading, or PAD-printing.^5,6 These DETs need to be operated at hundreds of volts to reach strains above 20%.^7,8 Recently, 200-nm-thin DETs have been manufactured using molecular beam deposition and operated at 12 V.⁹

In the last two decades, there have been several proposals for Intraoral Computer Interfaces (ICI), with demonstrations of novel technologies mostly aimed at assistive devices or in hand-free scenarios. This paper demonstrates a case study for wearable ICIs that allows users to train their tongue muscles with gamified myofunctional therapy: a method that can reduce snoring and mild sleep apnea. This demonstrates a novel application of ICIs together with new design and technological solutions for fabricating such devices. We also discuss the various challenges associated with the design of ICIs and ICI based interactions to lay the groundwork for future research, prototypes and a broader exploration of ICI application areas.

The effectiveness of a series of optically transparent aligners for orthodontic treatments depends on the anchoring of each tooth. In contrast with the roots, the crowns’ positions and orientations are measurable with intraoral scans, thus avoiding any X-ray dose. Exemplified by two patients, we demonstrate that three-dimensional crown movements could be determined with micrometer precision by registering weekly intraoral scans. The data show the movement and orientation changes in the individual crowns of the upper and lower jaws as a result of the forces generated by the series of aligners. During the first weeks, the canines and incisors were more affected than the premolars and molars. We detected overall tooth movement of up to about 1 mm during a nine-week active treatment. The data on these orthodontic treatments indicate the extent to which actual tooth movement lags behind the treatment plan, as represented by the aligner shapes. The proposed procedure can not only be used to quantify the clinical outcome of the therapy, but also to improve future planning of orthodontic treatments for each specific patient. This study should be treated with caution because only two cases were investigated, and the approach should be applied to a reasonably large cohort to reach strong conclusions regarding the efficiency and efficacy of this therapeutic approach.