Maxillary sinus grafting is a predictable regenerative technique to facilitate maxillary posterior implant placement when there is insufficient vertical bone height inferior to the maxillary sinuses to allow placement of implants of adequate dimensions. It enables an increase in vertical bone height, which makes implant placement easier. Maxillary sinus mucosal membrane perforation is one of the most common intraoperative complications during maxillary sinus grafting and may result in extrusion of graft material into the sinus. When this occurs, the mucociliary function of the maxillary sinus may expel the extruded graft material through its natural ostium, though graft particles may remain in the sinus or possibly occlude the natural ostium. After grafting, transient maxillary sinus mucosal oedema may occur. A postoperative CBCT scan may reveal varying degrees of sinus opacification, namely partial, subtotal or total. Although it is always possible to identify graft material, which may enter the sinus as a result of membrane perforation that might not even be visible to the implantologist during the surgical procedure, it is challenging to assess whether sinus opacification is due to mucosal thickening or mucus accumulation. The aim of the present case series was to offer a pragmatic approach to managing asymptomatic patients whose CBCT scans demonstrated partial, subtotal or total maxillary sinus opacification with bone graft particles that seemed to have been extruded into the sinus.