[Is a maxillary prosthesis difficult for patients with trismus?].

Of patients with a postoperative maxillary defect, around 30% are though to have trismus to some extent. In these patients, some difficulty in fabricating a maxillary prosthesis is expected. In this study, 54 patients with trismus were compared with a control group to find some proof of difficulty in making a maxillary prosthetics. Fifty-four of trismus less than 20 mm of a mandibular stroke were experienced out of 185 patients with maxillary prosthetics between October 1984 and October 1992. The trismus was divided into 4 groups of less than 5 mm (1 case), 5 mm-10 mm (10 cases), 11 mm-15 mm (19 cases), and 16 mm-20 mm (24 cases). These case were analyzed by in taking an impression failure, average weight of the prosthesis, time needed to complete the prosthesis and some special form of prosthesis. No apparent differences among the 4 groups or with the control group were found. The cause of the difficulty in making a prosthesis for such patients with trismus are suggested not to be simply due to the range of mouth opening but also to the complexed space formed by the dental defect, alveolar bone defect, spreadability of the lip and the cheek, the mandibular stroke and the so-called scar bundle of the cheek next to the defect.

[The chronological changes in the size of maxillary defect].

Use of a maxillary prosthesis is now considered one of the good methods to ameliorate the crippling caused by the defect in the maxillary palate area after an ablative procedure for a maxillary tumor and it consumes no physical resources from the patient. There has been debate on whether the prosthesis should be made in the very early postoperative days or after the wound is stabilized. In this study, changes in the area of the defect in the palate after surgery were investigated by using plaster models from clinical cases we have experienced. Twenty-one cases were investigated according to the following features: "maxillary sinus cancer "+" more than 1.5 years of follow-up for maxillofacial prosthetics "+" presence of more than two casts of the case". These casts were photographed from a distance of 1.5 m, and the photographs were enlarged to the original size of the cast, then the defect area was measured with a Planimeter (Uchida Co. Ltd). The area of the defect had shrunk in 16 cases. It took over 1 year to get stabilized in 80% of the cases. It is believed to take around 3.5 years for all cases to become stable. This tendency had no relationship with the pattern of the defect, the stroke of the mouth opening, the pattern of the rest of the teeth, or the defect area itself. These findings suggest that it may be advisable to start the prosthetic work as early as possible rather than waiting for stability of the defect wound, to improve the patients's QOL.