Abstract
Maxillectomy defects can be reconstructed by a prosthetic obturator or (free) flap transfer, but there is no consensus about the optimal method. This study evaluated 32 maxillectomy patients with prosthetic obturation regarding function (mastication, subjective oral and swallowing complaints and maximal mouth opening). Outcomes were related to the extent of the resection (Brown maxillectomy classification), dentition and history of adjuvant radiotherapy. Maxillectomy defects ranged from 2-1 to 4B on the Brown classification, and most had a defect graded as 2-A or 2-B. Mean mixing ability test after 10 chewing strokes was 24.2 and after 20 chewing strokes 19.7, which compares to edentulous healthy individuals. None of the outcomes was influenced by Brown classification. Radiotherapy negatively influenced mean maximal mouth opening (29.1 mm versus 40.9 mm, p = 0.017) and subjective outcomes. Edentate obturated patients had worse outcomes than dentate patients, measured by mixing ability test and questionnaire. In conclusion, mastication after obturator reconstruction of a maxillectomy defect is comparable to mastication with full dentures. Size of the maxillectomy defect did not significantly influence functional outcome, but adjuvant radiotherapy resulted in worse mouth opening and self-reported oral and swallowing problems. Residual dentition had a positive influence on mastication and subjective outcomes.
The incidence of patients undergoing a maxillectomy for maxillary cancer or oral cancer invading the hard palate is low. The annual incidence of maxillary sinus carcinoma is less than 1/100,000 inhabitants in the USA. In the Netherlands, in 2007 the incidence of oral cavity carcinoma was 5.4 per 100,000 inhabitants. Only 9% of all oral cavity carcinomas are localized in the hard palate and 12% at the gingiva.
Several epithelial subtypes of malignancies are found at the maxillary sinus: squamous cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, salivary gland carcinoma, or malignant melanoma. Treatment consists mainly of surgery and/or radiotherapy. The complex anatomy and proximity of many critical structures, such as the eye, brain and cranial nerves, makes planning treatment challenging. In cases of squamous cell carcinoma, concurrent chemoradiation with or without debulking can be considered for unresectable tumours, or if resection leads to an unacceptable functional result, known as functional inoperability.
Informing patients preoperatively about the expected functional result is of the utmost importance. A maxillectomy may induce severe functional problems due to disabling alterations in the functional components of occlusion, potentially leading to severely impaired mastication causing dietary changes. Other postoperative problems include hypernasal speech and nasal leakage.
To test the chewing function a wax compound method was chosen rather than a fragmentation method because of the difficulty collecting fragmented particles (particles disappear into the defect) and the higher risk of aspiration. Wax compound stays in one piece and does not have these disadvantages although it is sticky at first and becomes softer with rising temperature in the oral cavity during chewing. These disadvantages can be overcome by wrapping the tablets with saliva before the first chewing stroke. The wax can be pre-heated to mouth temperature.
Traditionally, restoration of hard-palate defects has been accomplished with palatal prostheses. This is a simple, non-surgical method to eliminate oronasal and oroantral communication, re-establishing normal speech and maxillary dentition. Other reconstruction options are non-vascularized grafts, local flaps, regional flaps and free revascularized tissue transfer. There is limited literature about function and quality of life issues in patients using an obturator prosthesis for primary reconstruction of a maxillectomy defects. The optimal reconstruction of the maxillectomy defect remains controversial.
In order to select patients carefully for different treatment options, and to provide sufficient preoperative patient counselling, the authors aim to evaluate function after a maxillectomy and prosthetic rehabilitation.
Materials and methods
The analysis was set up as a retrospective cohort study. The patient sample consisted of patients who underwent a maxillectomy as tumour ablative surgery between 1973 and 2009 and were still under recall at the special dental care unit of the Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital and/or the Center for Special Dental Care in Amsterdam. Selection criteria for searching the database were: ‘obturator prosthesis’ or ‘resection prosthesis’ or ‘maxillo-facial defect’. Medical charts were reviewed for inclusion criteria: patients with a definite obturator (approximately 1 year after surgery), location of the defect and the presence of an obturator prosthesis in the maxilla. All patients with a defect of the maxilla and obturator reconstruction were contacted by telephone. If they considered participating in the study, patient information was sent. Patients were excluded if they had a local recurrence, no prosthetic reconstruction, serious psychiatric or cognitive problems or if an extra visit to the hospital would be difficult due to physical conditions or distance (more than 45 min travelling).
Procedure
After a maxillectomy, a temporary obturator was fabricated peroperatively using gutta percha based on preoperative assessments and dental casts. This obturator was inserted immediately after tumour resection and remained in situ for the following 4–6 weeks, to prevent shrinkage of the maxillectomy cavity. In patients with large defects, the cavity was lined with a split skin graft. Two to three months post surgery an interim obturator was fabricated and after approximately 1 year the patient was provided with the definite obturator, made of acrylic resin based on Beumer’s method. This obturator protocol remained unchanged for the whole study period. Adjuvant radiotherapy was indicated by incomplete resection, bone invasion and multiple lymph node metastases or extracapsular growth. Patients with impaired mouth opening were offered physiotherapy and recently also the TheraBite Jaw Motion Rehabilitation System, a portable medical device used to stretch and strengthen swallowing and jaw muscles, specifically designed to treat trismus and mandibular hypomobility. The maxillectomy defects were graded according to Brown maxillectomy classification ( Fig. 1 ), and the oral cavity was inspected for remaining dentition.
