When reduced dimension implants are not indicated in the atrophic posterior maxilla, because of the relevant reduction of residual alveolar crest volumes following atrophy and/or expansion of the maxillary sinus, sinus floor elevation with a crest or lateral approach has become a quite frequent surgical procedure in implant dentistry. These surgical procedures, although reliable, may expose also experienced surgeons to complications such as:
1) sinus membrane tears;
2) penetration/migration of implants into their maxillary sinus;
3) post-operative maxillary sinusitis.