Parkinson's disease (PD) is a progressive neurodegenerative disorder. It is associated with reduced oral health and impaired oro-facial function, but besides recommendations of dental visits and drooling treatment, there are little documented odontological treatment options. To evaluate the effect of standardised home exercise jaw opening and chewing programmes, as well as home oral hygiene measures instructed and controlled by a trained dentist. Twenty-nine patients (median 65years) with moderate to advanced PD participated in the project after informed consent. They were followed at a Neurology Department, were able to cooperate, and had stable medical treatment and nine also deep brain stimulation. The interventions were individual dental hygiene instruction, training of jaw opening (JawTrainer), and lip and chewing exercises (Ulmer Oral Screen and Proxident Fluoride Gum). The study was performed as a randomised controlled study. The treatment effect was evaluated after 2 and 4months. The primary outcome was maximum unassisted jaw opening capacity, chewing time of a standardised apple slice, and the Simplified Debris Index. Results were analysed with Wilcoxon matched pairs test and Mann-Whitney U test (significance level P<.05). Jaw opening, chewing time and hygiene were significantly improved 2months from the start of the invention, respectively, 6%, 49%, and 25%, and the improvement was still significant after 4months. No significant changes were found after the 2-month control period without intervention. The simple measures had a substantial and significant clinical effect which is promising despite the progressive nature of the PD.