Patients with oromandibular dystonia who had either excessive jaw clenching or opening were compared with controls on levels of jaw muscle activity during simple mandibular movement on 3 planes. Those with jaw clenching had increased levels of masseter activity. However, those with jaw opening did not have increased levels in either the anterior belly of the digastric or the lateral pterygoid. Rather, the levels of muscle activity in the jaw openers did not change with changes in jaw movement direction. This absence of the normal pattern of muscle activity may explain why patients with excessive jaw opening do not benefit from treatment with botulinum toxin. The double blind crossover trial comparing clomipramine and desipramine in stuttering was completed in stuttering adults. Speech fluency improved significantly for the group as a whole on clomipramine and not on desipramine. However, there were individual differences with some individuals not improving on clomipramine. The long term effects over a year with a placebo interval are now being studied on those individuals who selected either medication for a one year trial. The results are encouraging and suggest that modifying serotonin may improve speech fluency. Stuttering subjects responses to treatment with thyroarytenoid injection of botulinum toxin were compared with patients with adductor spasmodic dysphonia and vocal fold tremor. The stuttering subjects had shorter periods of benefit and were less likely to return for re-injection than the other two groups. In addition, the stuttering subjects were more disturbed by the side effects, although these did not last longer than in the other patient groups. Thus although speech dysfluency may have improved, the treatment was not beneficial from the patients' perspectives.
