DISCUSSION.
The author’s impression is that the current complication is the result of excessive elevation of the schneiderian membrane during the bone grafting procedure. This usually results in a folded membrane superiorly positioned, which cannot be brought inferiorly to a lower position. This increased the dimension of the compartment to receive the bony graft material. As a result, the surgeon was forced to fill the entire area to the more superior level than was anticipated. The patient’s current symptoms are synonymous with the findings. The ideal treatment is to somehow approach the newly formed floor of the sinus and reduce the bone height to allow aeration of the sinus. This proposed procedure has never been attempted before; therefore, it will definitely need an otolaryngologist’s intervention. The current plan is to monitor the area for future surgical intervention. However, the patient decided not to pursue any further implant-related treatment and to have a maxillary partial denture fabricated for replacement of his missing teeth.

CONCLUSIONS.
This complication of excessive augmentation of the maxillary sinus could have been prevented with gentle elevation and meticulous manipulation of the sinus floor membrane as described in the literature.3–7 Measurement of the desired bone height should be done from the CT scan or the panoramic film before the procedure. During the procedure, elevation of the membrane should also be measured using periodontal probe or a ruler to avoid an overfill. Elevation of the membrane is always attempted by separating the membrane from the bony walls of the sinus. The membrane is folded in a superior position; therefore, it cannot be unfolded and brought inferiorly. If this occurs, then the best way to handle this complication is to abort the procedure rather than overfilling the sinus.
Another attempt can be accomplished in several weeks in which the membrane will eventually relapse toward the floor of the sinus. Although the findings in this case are highly unusual and not previously documented, it is proposed that an experimental procedure should be attempted to reduce the height of the excessive bone mass in the maxillary sinus. The approach, the technique, and the necessary armamentarium should be investigated. An otolaryngologist is being called upon to investigate this situation and its solution.

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