Neil H. Luyk

Control of vertical dimension during maxillary orthognathic surgery: A clinical trial comparing internal and external fixed reference points

The accuracy of vertical control during maxillary orthognathic surgery was assessed in 45 patients, comparing the use of traditional internal measurements across the osteotomy lines (15 subjects) with measurements between the incisor teeth and an external reference point consisting of a bone screw placed at nasion (two groups of 15 subjects each). Although use of a fixed external reference point can significantly decrease positioning error (p < 0.001), considerable care is required during application of rigid fixation to maintain the correct vertical dimension.

Temporalis muscle as a disc replacement in the temporomandibular joint of sheep.

Temporalis muscle flaps were evaluated in sheep. Flaps placed following discectomy were examined at 2, 4, 12, and 24 weeks. Histologic evaluation showed avascular necrosis and subsequent displacement and loss of tissue from the joint resulting in close contact between the condyle and fossa. Muscle flaps placed lateral to the joint in operative controls were examined at 4, 12, and 24 weeks. This muscle remained viable while undergoing fibrous replacement. Although the surface layers of the condyle and fossa were initially lost, the tissues were reformed with time. This experiment showed that in the sheep, temporalis muscle does not withstand functional loading within the joint. However, despite the lack of interpositional material, the condyle and fossa can remodel.

Patient-controlled sedation using midazolam.

Midazolam was given for sedation as an initial bolus, followed by either a continuous infusion or a patient controlled infusion during third molar extractions. The results showed that there were no significant changes in blood pressure, pulse rate or oxygen saturation during the procedure. Both methods gave good amnesia to events at the start, (100%), as well as to events during, (70% and 75%), and at the end, (61% and 70%), of surgery. There was high acceptance of both methods of sedation (93% and 98% respectively). There was no patient preference for either method of sedation, nor was the operator able to distinguish between the two methods. Hence it is concluded that patient controlled infusion and continuous infusion of midazolam are both satisfactory methods of sedation for patients undergoing surgery under local anaesthesia.

Efficacy of oral midazolam prior to intravenous sedation for the removal of third molars

The combination of oral and intravenous sedation has not been well investigated and this study examined the combinations effect on amnesia, anxiety, cardiovascular stability and recovery in a double blind, cross-over, placebo controlled trial. Patients were given 7.5 mg oral midazolam or placebo 1 h prior to intravenous midazolam and surgery. This investigation demonstrated significant anxiolysis, amnesia and patient preference for oral midazolam compared to placebo. There was no significant effect on cardiovascular stability, the intravenous dose of midazolam used or post-operative recovery. Low dose oral midazolam prior to intravenous sedation may be beneficial in very anxious patients, particularly if surgery is delayed.

A potential role for costo-chondral grafting in adults with mandibular condylar destruction secondary to rheumatoid arthritis—a case report

Little attention has been directed towards reconstruction of the mandibular condyles in adult patients with rheumatoid arthritis, other than with allogenic implants which are now known to cause serious complications. There is a relatively high incidence of condylar erosion and breakdown in rheumatoid arthritis, often leading to anterior open bite and retrognathia. Costochondral grafting does not appear to have been considered as a logical option for reconstruction, despite its high success rate in many other situations. A case is described of rapid bilateral condylar destruction occurring in a young woman with rheumatoid arthritis, leading to anterior open bite. Reconstruction was undertaken using bilateral costochondral grafts, giving an excellent clinical result which has been maintained over the follow-up period of two-and-a-half years. Radiologically complete healing of severe glenoid fossa erosion has taken place.

Bolus dose with continuous infusion of midazolam as sedation for outpatient surgery

This double-blind, randomised, cross-over trial in 41 patients for 3rd molar surgery compared the safety, amnesic properties and psychomotor recovery between a bolus injection of midazolam and a bolus injection followed by continuous infusion of midazolam. The latter showed good safety and better amnesia to events during the procedure, but prolonged the recovery time.

The diagnosis and initial management of the fractured mandible

Mandibular fractures are the second most common facial fracture. The usual causes are interpersonal violence and motor vehicle accidents (MVA). Nearly all cases present to an emergency department for initial management. They are rarely life-threatening injuries and must assume low priority in the initial assessment and management of the severely traumatized patient. Following any resuscitation and exclusion of other significant injuries, a clinical and radiologic diagnosis of the facial injuries should be undertaken including assessment of the fractured mandible. Initial therapy should be directed at temporary immobilization and pharmacologic treatment, followed by referral for appropriate definitive care.

Facial pain and muscle atrophy secondary to an intracranial tumour

Orofacial pain rarely arises from a distant site. It is unusual for orofacial pain to be associated with wasting of the facial musculature and diminished sensation. This case report describes a patient who presented with temporomandibular joint pain dysfunction syndrome which was initially successfully managed with splint therapy. She re-presented later with unilateral wasting of the muscles of mastication, facial pain and diminished sensation ipsilaterally. An intracranial meningioma was diagnosed following an extensive series of investigations.