Anatomical Risk Factors For Complications During Maxillary Sinus Floor Elevation In The Fenestration Of The Lateral Wall

Sinus floor elevation technique makes possible implant placement and restoration in the maxillary molar region with insufficient bone height,and the clinical outcome has proved to be reliable and predictable.Currently it has been widely accepted as a regular bone augmentation technique for reduced bone volume in the maxillary molar region.Sinus floor elevation is mainly divided into two techniques:transcrestal sinus floor elevation and lateral window sinus floor elevation.The latter one has been applied in clinical practice for several decades.However,several potential complications may arise during this procedure,such as perforation of sinus mucoperiosteum,profuse bleeding,unfavorable primary stability of implant and dislocation of bone grafts.Potential anatomical risk factors during lateral window sinus floor elevation include sinus mucoperiosteum,vascular anatomy of sinus lateral wall,sinus septa,sinus cyst,etc.It is essential for surgeons to gain a thorough understanding of anatomical risk factors and to learn the proper way to deal with them during surgery,so as to reduce the incidence of complications and improve the clinical outcome.By utilizing cone beam computed topography(CBCT)scanning before surgery,surgeons will have a better understanding of sinus anatomy and the presence of potential risk factors.Besides,surgical procedure modification and lateral window design innovation also diminish the risk of complications.With this narrative review,we aimed at illustrating the anatomical risk factors during lateral window sinus floor elevation,in order to give the clinician a reference when planning for a lateral window sinus floor elevation surgery.Objective:Three case reports of lateral window sinus floor elevation with big caliber artery in sinus lateral wall.Analysising potential risks of intraoperative bleeding complication and correspondent solutions.Methods:Case one,lateral window sinus floor elevation in right maxillary with an intraosseous alveolar antral artery in the surgical region.The diameter of the artery was 1.7 mm.We made the superior margin of lateral window inferior to the artery without causing any damage to the artery.Case two,lateral window sinus floor elevation in left maxillary with an partially intraosseous alveolar antral artery in the surgical region.The artery was in close proximity with sinus mucoperiosteum with a diameter of 2 mm.We detached the sinus mucoperiosteum along with the artery to avoid lacerating the artery.Case three,lateral window sinus floor elevation in left maxillary with an intraosseous alveolar antral artery in the surgical region.The diameter of the artery was 2.3 mm.We lacerated the artery by accident,resulting in pulsatile hemorrhage and mucoperiosteum perforation during the surgery.We managed to stop bleeding by filling the bone canal with collagen sponge,combining with diode laser irradiation and compression.Results:Case one and case two underwent lateral window sinus floor elevation with simultaneous implant placement without causing any bleeding complication.As for case three,lateral window sinus floor elevation was successfully carried out after 1-year recovery.Conclusion:Lateral window sinus floor elevation has a potential risk of massive bleeding during surgery.It’s essential for surgeons to gain a sound knowledge of the sinus vascular anatomy and master the skills to prevent and treat this kind of situation.