Early loading of angled implants in maxillectomy with ...

Early loading of angled implants in maxillectomy with radial forearm free flap reconstruction - a new paradigm. Butterworth C* *Consultant/Hon Senior Lecturer in Maxillofacial Prosthodontics,
 Department of Molecular & Clinical Cancer Medicine, University of Liverpool, UK.

Background: The rehabilitation of the maxillectomy patient is complex with a variety of options available to the head & neck cancer team from obturation to reconstruction using pre-fabricated composite flaps. The development of highly specialised tools such as zygomatic, oncology and co-axis implants have provided a platform for effective dental rehabilitation in an early timeframe following surgery. Boyes-Varley et al. (2007) successfully demonstrated the use of early loading in this cancer setting utilising oncology and dental implants together with prosthetic obturation. Whilst implant survival was not a problem, the amount of prosthodontic maintenance was significant and most likely related to the complex issues around maintaining an oro-nasal seal in a changing maxillectomy cavity. We present an early-loading zygomatic and oncology implant protocol for maxillectomy patients incorporating microvascular free flap closure of the defect with a radial forearm flap and early delivery of a fixed dental prosthesis within a few weeks following surgery.

Protocol: In our protocol, 1 to 2 oncology zygomatic implants are placed primarily into the residual zygomatic body on the resected side after the maxillary resection together with coaxis implants into residual alveolar bone (healed sites/ immediate socket placement).

CASE 1 Where the residual alveolar bone on the non-defect side is limited, conventional placement of zygomatic implants is undertaken. AMCZ abutments are placed and abutment level impressions are taken with preliminary splinting utilising light-cured resin tray material to minimise inaccuracies across the defect which is packed during the impression. Abutment protection caps are then placed (HMC 4/6) to facilitate jaw registration which is taken using either the patient’s own complete denture prosthesis (case 1) or a prepared registration prosthesis (case 2).
 The radial forearm free flap (RFFF) is then disconnected from the arm and inset into the maxillary defect. The flap is carefully perforated over the implant abutment protection caps using a scalpel taking care not to damage the pedicle within the flap and ensuring a tight adaptation of the flap around the abutment. The flap anastomosis is then completed and the neck wound closed.The initial reinforced acrylic screw retained prosthesis is then constructed by the technician and fitted at approximately 3-4 weeks postoperatively depending on the progress of the patient.

Discussion

CASE 2 Reference

This protocol has many advantages over the current alternatives for low-level maxillectomy defects. The use of a simple soft tissue RFFF allows autogenous obturation of the defect reducing prosthodontic maintenance, oro-nasal reflux and allowing more elderly/medically compromised patients to receive autogenous reconstruction. The use of oncology and zygomatic implants provide a predictable foundation for early prosthodontic loading within a few weeks of surgery using well described techniques. This provides a rapid return to function and appearance for patients whose future prognosis is often uncertain or limited, with many going on to receive post-operative radiotherapy. In comparison, the use of digitally planned composite reconstruction techniques are more complex, costly and require patients without significant peripheral vascular disease. Implants installed into composite flaps, in this author’s view, are far less predictable in supporting an early-loaded and often quickly irradiated implant prosthesis.

Boyes-Varley JG, Howes DG, Davidge-Pitts KD, Brånemark I, McAlpine JA. A protocol for maxillary reconstruction following oncology resection using zygomatic implants. Int J Prosthodont. 2007 Sep-Oct;20(5):521-31.

Department Maxillofacial Prosthodontics, Regional Head & Neck Cancer Centre, Aintree University Hospital, UK.
 www.maxillofacialprosthodontics.uk