Effectiveness of clear aligners treatment in class I angle dental arch abnormalities

The relevance of the problem and the aim of the work: Invisalign aligners – it is a modern orthodontic treatment system which was the first to use digital 3D teeth position modeling and manufacturing methods. Despite clear aligners system advantages it‘s a rather new technology and because of that it is uncertain if the system is capable of teeth straigthtening and occlusal correction function. The aim of this work – evaluation of clear aligners treatment effectiveness on class I orthodontic abnormalities through a systematic review. Material and methods: From a total of 5977 articles there was only 13 which complied with selection criteria - 4 prospective, 9 retrospective. 5 articles evaluated thermoplastic aligners treatment effectiveness in teeth crowding, 2 - in teeth distalization, only 1 - in treatment of deep bite, 2 – in treatment of open bite. 3 - articles evaluated predictability of orthodontic movement, 2 – evaluated orthodontic tooth movement effectiveness using clear aligners. Results: There was found one article with strong evidence, others only mediocre. When teeth crowding is 4-6mm and above treatment with Invisalign system causes slight increase of dental arch width and incisors proclination even when using IPR. When staging aligners to distalize teeth for 0,25mm per two weeks the biggest effectiveness (87%) is achieved moving upper molars. When deep bite is ≥4mm, it decreases 1,6mm on average. Treatment result morphological basis – mandibular incisors proclination and upper incisors intrusion. In treatment of moderate open bite cases, vertical incisors overlap increases by 3,3mm because of both jaws incisors extrusion and molars intrusion. The predicted result precision by ClinCheck in the mandibular: vestibulolingual tipping of canines 0,66%, canines rotation 0,54%, incisors rotation 0,67%, in maxilla mesiodistal tipping of caines, premolars, molars and molars rotation is close to 100% of predicted treatment result. Conclusion: If teeth crowding is 4mm and above non-extraction treatment with clear aligners increases incisors vestibulolingual tipping and deantl arch width even using IPR. Invisalign clear aligners efectiveness in upper molars distalization is 86,9%. Average second molar distalization distance is 2,52mm, first molar – 2,25mm. Invisalign clear aligners are effective in treatment mild and moderate deep bite cases but it causes an increase in buccolingual incisors proclination for lower jaw. Aligners are also effective in mild and moderate open bite treatment by using both jaws incisors extrusion and molars intrusion. Clinchek modelated end result treatment view will not match the final clinical treatment result