Parkinson’s Disease (PD) is one of the most common neurodegenerative diseases worldwide,
affecting various parts of the body and several aspects of daily life. The motor and non-motor
symptoms of the disease, along with the pharmaceutical side effects, have a negative impact on oral
health and orofacial function. This manifests as an increased risk of oral diseases and impaired
orofacial function.
However, several aspects have not been previously elucidated. Firstly, it is unclear whether the
dental care needs are being met for persons with PD. Secondly, clinical systematic and
comprehensive assessment of the orofacial function and temporomandibular dysfunction is scarce.
Lastly, there is a notable absence of documented options for improving the orofacial function and
oral health for this patient group.
This PhD project is composed of three studies aiming to fill these knowledge gaps. Study I aimed to
examine dental care utilization. This was accomplished through a register-based study that identified
the entire PD population in Denmark, comparing them with a five-fold control group without PD.
Dental attendance and services received over a five-year period were analysed while adjusting for
socioeconomic and other relevant variables. Study II was a case-controlled study, aimed to
investigate clinical orofacial function and orofacial pain. This was conducted comprehensively and
systematically using standardised methods and electromyography, alongside relevant self-reported
outcomes. Study III aimed to explore whether orofacial function and oral hygiene could be improved
for this patient group. This was done in a randomised controlled trial, where participants were trained
in a standardised exercise program to enhance orofacial function and individual oral hygiene
instructions to improve oral health.
Study I revealed that persons with PD exhibited a higher irregular attendance in the dental care
system. Additionally, they had a significantly higher usage of dental care services, particularly for
treatment purposes. For instance, persons with PD had a 1.5 times higher incidence rate of tooth
extractions and a 1.71 times higher incidence rate of tooth fillings over a span of five years compared
to persons without PD. Study II showed that persons with PD displayed poorer orofacial function as
they had significantly reduced masticatory and swallowing function and reported significantly more
xerostomia and drooling than persons without PD. Furthermore, orofacial pain was more prevalent
among persons with PD. Study III revealed that the orofacial function, oral health and oral healthrelated
quality of life could be improved by the intervention involving orofacial exercises and oral
hygiene instructions. Two months of intervention resulted in a 25% decrease in chewing duration, a 6% increase in the maximum jaw opening capacity and an approximately 50% decrease in dental
plaque.
In conclusion, the irregular usage of dental care and higher usage of dental treatment services
indicate a potential for prophylactic initiatives for this patient group. Furthermore, healthcare
professionals should be aware of the compromised orofacial function and address these issues in due
diligence. One possible approach could be to involve the intervention from study III, which has the
potential to delay PD's negative impact on orofacial function and oral health, thereby enhancing the
overall health and quality of life for persons with PD. To put this into perspective, there is an
opportunity for dental health care professionals to contribute to this patient group as part of a
multidisciplinary approach to this disease.