The use of a bioabsorbable root analog made of β-tricalcium phosphate for closure of oroantral fistulas was proposed by Thoma et al. [68]. The root replicas were fabricated chair side, using a mold of the extracted tooth [10]. The investigators reported that the healing was uneventful. However, fragmentary roots or overly large defects prevent replica fabrication or accurate fitting of the analog. The technique is simple and fast.

Kitagawa et al. advocated third molar transplantation as a suitable option for closure of OAFs [69]. The investigators successfully closed two cases of OAFs by immediate upper and lower third molar transplantation.

The donor teeth were carefully extracted and transplanted to the prepared recipient bed. Firm finger pressure and light tapping provided good stabilization of the tooth on the recipient bed and produced a complete simultaneous closure of the OAF. Endodontic treatment was carried out after 3 weeks. The researchers reported that third molar transplantation was a simple and excellent treatment option to close small OAFs. However, third molar transplantations have some drawbacks: the requirement of a sufficiently developed third molar of an appropriate shape and size, and the risks of ankylosis and root resorption if not carried out with proper technique.

Hori et al. proposed interseptal alveolotomy as one of possibilities for closure of OAFs [70]. The technique, based on the Dean preprosthetic technique, is used for the purpose of smoothing the alveolar ridge. The extended Dean technique is performed in such a way that the interseptal bone is removed, followed by the fracturing of the buccal cortex in the direction of the palate. Sutures are used for soft tissue closure. The technique offers the advantage of facilitating spontaneous postoperative healing with less postoperative swelling, supported by the bony base. The most important advantage of this technique, compared with the buccal flap technique, is that it assures closure of soft tissue without creating tension. However, limitations of this method are that it requires both a space of less than 1 cm between the adjacent teeth and adequate alveolar ridge. Moreover, there is a risk of inflammation as a result of the required buccal bone fractures due to formation of bone sequesters and possible imperfect soft tissue closure in the case of an incomplete fracture.