With growing elderly population, the interest for oral rehabilitation for elderly people has been increased. To rehabilitate oral condition, dental implant is an increasingly common restoration for the replacement of missing teeth. The success of dental implants does not appear to be affected by age, however, some systemic disease can affect the long term outcome of dental implant. Therefore, the elderly people should be considered their systemic conditions before placing dental implants, because they often have systemic diseases with reduced immune function and take a variety of medicine. It is vital to control the medication with cooperation between dentists and physicians. Furthermore, when placing the dental implants to elderly people, minimal invasive or flapless implant surgery could be considered. With consideration for systemic condition factors and proper periodic maintenance, it could be expected to be successful for dental implant treatment for elderly people.

Screw loosening and consequent screw fracturing are the main causes of mechanical complications of implants. When an abutment screw is fractured, the screw has to be removed and replaced without damaging the implant fixture thread for the new abutment. However, if the internal threads of the implant are unexpectedly deformed, implant removal may be required. Here, we introduce an alternative technique for salvaging an internally damaged implant using the custom cast post as an implant abutment without removing the implant.

The purpose of this study was to review the literature related to implant deviations that may occur when using a computer-guided implant surgical guide and to consider clinical precautions to reduce these deviations when placing implants using a computer-guided implant surgical guide. Materials and Methods:Articles published between 2010 and 2020 were searched in PubMed according to custom criteria. The selected articles were classified according to the cause of the deviation, and the degree of the deviation was analyzed.Results: Twelve articles were included based on the selection criteria. During implant surgery using a computer-guided implant surgical guide, various implant deviations were observed depending on the implant location, sleeve, drill, implant system, residual teeth, and 3D printer type. Conclusion:Deviations in implant placement can occur even when computer-guided implant surgical guide are used. It is necessary to recognize the possibility of implant deviations occurring according to various clinical situations and attempt to reduce these deviations.

When restoration for partially edentulous patients, abutments are not always in favorable positions for making removable partial dentures. Because of these situations, patients are sometimes unsatisfied with the stability and support of their removable partial prostheses. In this regard, removable partial denture using a few implant surveyed crown prostheses can be a good alternative. It can be expected to increase stability and support of removable partial dentures by strategically placing a small number of implants and restoring with implant-supported surveyed crowns. In these cases, the patients who had unilateral residual teeth on mandible were treated with two implant surveyed crowns in the tactical place to have bilateral distribution. After definitive removable partial prosthesis, the patients showed satisfaction with the masticatory function and comfort of using removable dentures.