Closure of oroantral communications using biodegradable polyurethane foam; a prospective clinical trial

An oroantral communication (OAC) is an open connection between the oral and
paranasal cavity. In general, an OAC is caused by extraction of maxillary
(pre)molars. Although the incidence is relatively low, OACs are frequently
encountered due to the high number of dental extractions. To minimize the risk
of chronic sinusitis and the development of fistulas, it is generally accepted
that all OACs should preferably be closed within 24 hours. Surgical closure
with a mucoperiosteal flap is the treatment of choice nowadays. The patient has
to be referred to a maxillofacial surgeon for this treatment, because in
general the dentist does not have the expertise and the facilities to treat an
OAC himself.
Another major objective of the surgical treatment for edentulous patients is
the fact that the buccal sulcus depth almost certainly decreases permanently
after closure with a buccal flap, thereby hindering the fitting of a
well-fitted dental prosthesis.
The proposed treatment with a biodegradable polyurethane foam meets this
objections because it is a quick, safe and simple strategy and does not require
additional surgical skills. This will make it possible for a dentist to treat
an OAC himself, instead of having to refer the patient to the maxillofacial
surgeon. Furthermore, the proposed treatment has no influence on the buccal
sulcus depth. In addition, the PU treatment gives rise to less postoperative
pain and swelling. Lastly, due to the biodegradability of the foam, a second
visit for removal of the foam is not necessary

Goal of this study is to assess the treatment of OACs with biodegradable
polyurethane foam, as carried out in the pilot studies, in a large number of
patients.

The study is a supplemental study to the previous pilot studies. In the second
pilot study the PU treatment and its protocol were perfectioned. In the current
study the treatment will be evaluated on a larger scale. A group of maximally
108 patients with fresh OACs will be treated with PU foam. A stopping rule will
monitor the ending of the study in case the results are either more positive or
more negative than anticipated. Based on a study on the complication ratio
after surgical closure of OACs, and the results of both pilot studies, it is
expected that the number of recurrences of OACs will be between 5 % and 12,5 %.
The data will be analysed sequentially to minimize the need of included
patients in order to gain statistically significant results.
Each patient with a oroantral communication on the outpatient department of
oral and maxillofacial surgery will be evaulated on the inclusion criteria.
Next, each selected patient will be treated with PU foam until statistically
significant results are obtained.

All included patients will be treated in the same manner. The size of the
oroantral communication will be examined and a polyurethane foam is selected
that matches its size. Secondly a safety-suture is attached to the PU foam to
facilitate removal of the foam in case it is accidentally pushed through the
perforation into the maxillary sinus. Hereafter, the foam is fitted in the
perforation and the safety suture is removed. Lastly, the PU foam is loosely
secured on the oral side with a suture to ensure the PU foam stays in place.

To our point of view the proposed treatment implies both a minimal risk and
burden for the patients involved in the study. Firstly, the treatment is
quicker than the conventional surgical treatment. Secondly, the swelling and
postoperative pain are less prominent after closure with PU foam. Furthermore,
the most important risk associated with participation in the study is possible
recurrence of the OAC. However, in such cases, the attending physician can
always fall back on the conventional surgical treatment. Laslty, the number of
policlinical visits asscociated with participation in the study is restricted
to 3 visits, which is only slightly more than usual (2 visits)