The internal “rings” (“lingual” technique), are based on the same principle as the visible “rings”, but these are glued on the internal surfaces not visible externally (lingual below, palatal above). They have the advantage of making the treatment practically invisible but have the disadvantage of being able to interfere with speech and, sometimes, injure the tongue. Lingual orthodontics is a demanding technique that allows treatments to be performed with absolute discretion. The appliance is placed on the lingual surface of the teeth, so it is perfectly invisible from the outside. This is a significant advantage over fixed vestibular ‘remarkable’ appliances or so-called discreet aligners because they are slightly visible in contrast to the surface of the teeth. Lingual brackets feature custom 3D bases fabricated following a 3D intraoral scan. Lingual arches are manufactured by 3D robots which express 3D deformations which allows the movements made to be optimized. They do not involve any particular constraints or side effects except sometimes speech constraints of a few hours which can sometimes be observed in people with a bulky tongue or with too anterior lingual swallowing when the appliance is used. positioned at the level of the lower arch. In these cases, the lower lip covering the lower teeth in general, a mixed solution is sometimes proposed with an external appliance at the level of the lower arch as well as a lingual appliance at the level of the upper arch which allows to have a treatment in all discretion while having an optimized speech comfort and swallowing. We are proud to have been able to participate in the promotion of a revolutionary self-ligating lingual system that appeared on the market more than 10 years ago and are considered experts in this demanding technique.