Orofacial dyskinesia (ODk) is an involuntary, repetitive and stereotyped movement disorder of the oro-bucco-lingual muscles, which can be classified as primary (idiopathic) or secondary to medical conditions such as oral peripheral factors, that may act as triggers or aggravators. The present case describes a 70 years female with ODk, non-associated to drug use, without central etiological factors or morbid conditions, but with the presence of a flawed prosthodontic treatment, which complaint from spasms in the masticatory muscles that alters jaw dynamics, and her ability for maintain a relaxed jaw in maximal intercuspal position. After an unsuccessful oral drug treatment, botulinum toxin was injected to the jaw muscles with favorable results. The case illustrated that peripheral factors, such as defective dental prosthetics, may trigger or aggravate orofacial movement disorders, and peripheral strategies such as botulinum toxin may contribute to improve clinical parameters and quality of life.