Diverse Indications for Zygomaticus Implants - A Case Series
Franco, Peter B. DMD; Brecht, Lawrence DDS; Bourell, Lauren G. DDS MD; Hirsch, David L. DDS MD FACS
Statement of the problem: Reconstruction of the atrophic edentulous maxilla can be a challenge, particularly in individuals where extensive bone grafting is required prior to dental implant placement or in patients where bone grafts have been tried and failed. Likewise, dental rehabilitation after tumor ablation and reconstruction can be problematic if there is inadequate maxillary bone to support traditional dental implants. Zygomaticus implants, which make use of the dense type I-II bone of the zygoma, are one solution which allows for dental implant reconstruction of the atrophic or reconstructed maxilla.
Materials and methods, data analysis: We performed a retrospective chart review of all patients who received dental implants in the operating room at two of our affiliated hospitals from June 2007 to March 2013. We identified those patients who received either unilateral or bilateral zygomaticus implants. We then collected available data including gender, diagnosis, adjunctive surgical procedures, and indication for zygomaticus implants. Patients receiving zygomaticus implants following maxillectomy procedures were compared to a cohort of patients who did not receive implants following maxillectomy to determine which variables may have influenced surgeon choice of zygomaticus implants. In addition, we report on two recent cases of zygomaticus implants placed following enucleation of maxillary bone cysts. Follow-up was available for all patients and ranged from one month to five years. All implants were placed by and with the supervision of a single attending surgeon, DLH.
Results: From 2007 to 2013, a total of 25 zygomaticus implants were placed in twelve patients at two affiliated hospitals. Indications for zygomatic implants were varied. Patients received zygomatic implantation for cleft reconstruction, maxillectomy defect with and without free tissue transfer, and atrophic maxilla not amenable to traditional implant surgery. Two patients received bilateral zygomaticus implants for a diagnosis of atrophic, edentulous maxilla—one of whom also received bilateral anterior conventional dental implants. Three patients received unilateral zygomaticus implants after ablation of maxillary malignancies (mucoepidermoid carcinoma, acinic cell carcinoma, and squamous cell carcinoma)—two patients as a secondary procedure, and the other at the time of the tumor ablation. Two patients received unilateral single zygomaticus implants in conjunction with single conventional dental implants simultaneous with treatment of benign maxillary bone cysts (aneurysmal bone cyst, other bone cyst). Five patients received unilateral zygomaticus implants after ablation of benign tumors including ameloblastoma and central hemangioma. Of note, two patients received radiation therapy after zygomatic implants were placed, without complication.
All zygomaticus implants integrated successfully. Complications included 1 implant removal due to chronic soft tissue infection and one conjunctival laceration after inadvertent entry into the orbit. All patients successfully received dental rehabilitation.
Conclusions: In an individual with an atrophic maxilla or with significant bone loss from a destructive cyst of the maxilla, zygomaticus implants can shorten treatment time by obviating the need for bone grafting. They can also provide a solution when bone grafts have been tried and failed, or in post-reconstructive situations to support obturators or other dental prostheses. We highlight these diverse uses in twelve patients from two of our affiliated institutions.
References:
Hirsch, David L. Howell, Kacey L. Levine, Jamie P. A novel approach to palatomaxillary reconstruction: use of radial forearm free tissue transfer combined with zygomaticus implants. J Oral Maxillofac Surg. 67(11):2466-72, 2009 Nov.
Panagos, Petros. Hirsch, David L. Resection of a large, central hemangioma with reconstruction using a radial forearm flap combined with zygomatic and pterygoid implants. J Oral Maxillofac Surg. 67(3):630-6, 2009 Mar.