LAUSR

tps://doi.org/10.1016/j.jds.2020.11. 91-7902/a 2021 Association for Denta e CC BY-NC-ND license (http://creati Restoring a full edentulous maxilla or mandible with only 4 dental implants can be a reliable treatment. The denture can be fixed or removable and the retention can come from attachments, bars, screws or cement. Nowadays, conometric retention is considered as a good alternative option in advance. Despite the improvement of retention, in severe atrophic mandible, the chewing function was still restricted by anatomic limitation: the presence of inferior alveolar nerve and mental foramen. Here, we presented a female patient who suffered from severe resorption of mandibular alveolar ridge and floating of her lower partial denture (Fig. 1A and B). Keeping her residual mandibular teeth and implantation at teeth 32 and 34 (above mental foramen) for a new implant-supported removable denture was suggested first. However, she refused any removable solution and demanded a fixedmolar-occlusion denture. After treatment plan discussion and risks explanation for many times, the treatment plan was confirmed as follows: bilateral maxillary sinus lifting, bilateral inferior alveolar nerve repositioning, extraction of all the mandibular teeth, alveoloplasty, 4 Ankylos implants, and placement of 3 temporary mini-implants under general anesthesia at one time. Maxillary first molars were