Case reportPages 43-52, Language: EnglishEiny, Shmuel / Elianov, Olga / Aizenbud, Dror
Clear aligner treatment has significantly improved throughout the last decade and is recommended for more complicated orthodontic treatment. However, torque movement is still challenging when achieved by clear aligners. In this case report, a 20-year-old patient who underwent orthodontic treatment during childhood, retained by a mandibular canine- to-canine fixed retainer, was referred to the clinic by a periodontist. Her mandibular right lateral incisor (tooth 42) was torqued in, and central incisor (tooth 41) was torqued out with a reciprocal torque difference. A 4-mm lingual recession and 6-mm labial recession was attributed to retainer-caused inadvertent tooth movement. Torque differences were also demonstrated on the maxillary central incisors (tooth 11 and tooth 21). An orthodontic correction of axial inclination of mandibular incisors and movement to their normal positions was planned. The patient was scheduled for periodontal free-gingival graft on the central incisor, post-orthodontic treatment. Within 18 months, the treatment with clear aligners, interproximal reduction and Class III elastics was successful, resulting in torque correction of teeth 41 and 42, and alignment of the dental arch teeth. Torque of teeth 11 and 21 was achieved. Fixed retainers were fabricated for six maxillary and mandibular anterior teeth combined with Essix nightwear retainers for long-term stability. A dead-soft passive wire was chosen to avoid retainer-caused complications. The graft surgery was postponed due to improved prognosis of the mandibular central incisor, significant reduction in gingival recession and the presence of a thin layer of keratinised gingiva. Orthodontists, general dental practitioners and patients should be aware of the possible complications of fixed retainers and orthodontic correction.
Keywords: clear aligners, fixed retainer, free graft, gingival recession, Invisalign, mandibular incisors inclination, orthodontics, torque