The doctoral dissertation in the field of Oral Public Health will be examined at the Faculty of Health Sciences at the Kuopio campus.
What is the topic of your doctoral research?
This dissertation aimed to study the possible associations of temporomandibular disorder (TMD) -related joint and muscle pain with the presence of migraine and tension-type headaches in one cross-sectional study and two longitudinal studies.
What are the key findings or observations of your doctoral research?
According to the results, muscle-related TMD pain was associated with the presence of migraine at a cross-sectional level, but not longitudinally. However, muscle-related TMD pain was found to predict the presence of tension-type headaches over a follow-up period of 11 years. Joint-related TMD pain was not associated with the presence of either migraine or tension-type headaches longitudinally. TMD-related pain as a co-morbidity of migraine was associated with both higher frequency of migraine and headache medication consumption.
The results may point toward the existence of diverse mechanisms that play a role in the prospective and long-term associations between different TMD-related painful conditions and primary headaches.
How can the results of your doctoral research be utilized in practice?
Knowledge on the risk factors of primary headaches may lead to new and better approaches for their prevention and treatment. Thus, integration and incorporation of a multidisciplinary approach in the treatment of both TMD-related pain and primary headaches would have a significant advantage in their treatment strategies, as well as in their prognoses.
Future studies on the determination of TMD-related signs and symptoms, including TMD-related pain, should be conducted at both the epidemiological and physiological levels for the accurate determination of both the prevalence and detection of important co-morbid conditions associated with TMD. Furthermore, the data on potential risk factors and confounders of TMD-related pain should be collected and adjusted for the application of modern epidemiological methodologies. Newer knowledge and a deeper understanding of the existing mechanisms may also lead to better prevention and treatment of these debilitating disorders.
What were the key research methods and materials used in your doctoral research?
This thesis utilized the study samples from the Health 2000 Survey and the Health 2011 Survey. Both of these population-based nationally representative health surveys were organized by the Finnish Institute for Health and Welfare (THL), former National Public Health Institute of Finland (KTL), in co-operation with the researchers and experts from several other organizations in Finland.
Directed Acyclic Graphs (DAGs) were utilized for the correct identification and selection of the studies (II and III) confounders. Both Frequentist and Bayesian Logistic Regression models were utilized for predictive associations. Sensitivity analyses for unmeasured confounding in frequentist analyses were conducted through use of E-values. For verification of stability of estimates, in Bayesian Domain, sensitivity analyses were carried out with widely heterogeneous prior distributions.
The doctoral dissertation of Javed Ashraf, BDS, MPhil, entitled Association between temporomandibular-disorder-related pain and primary headaches – results of Finnish population-based surveys will be examined at the Faculty of Health Sciences. The Opponent in the public examination will be Professor Thomas List of the University of Malmö, and the Custos will be Professor Emeritus Matti Närhi of the University of Eastern Finland. The public examination will be held in English and it will be streamed online.