Advances in precision oral health

The concept of precision dentistry as it relates to precision medicine is relatively new to the field of oral health. Precision dentistry is a contemporary, multifaceted, data-driven approach to oral health care that uses individual characteristics to stratify similar patients into phenotypic groups. The objective is to provide clinicians with the information that will allow them to improve treatment planning and a patient's response to treatment. Providers that use a precision oral health approach would move away from using an “average treatment” for all patients with a particular diagnosis and move toward more specific treatments for patients within each diagnostic subgroup. Precision dentistry requires a method or a model that places each individual in a subgroup where each member is the same as every other member in relation to the disease of interest. Precision dentistry is a paradigm shift that requires a new way of thinking about diagnostic categories. This approach uses patients’ risk factor data (including, but not limited to, genetic, environmental, and health behavioral), rather than expert opinion or clinical presentation alone, to redefine traditional categories of health and disease. We review aspects of current efforts to allow precision dentistry to be realized and focus on one of the major innovations that may help precision dentistry to be practiced by periodontists, the World Workshop Model. Another approach is the Periodontal Profile Class system. These two approaches represent examples of supervised and unsupervised learning systems, respectively. This review compares and contrasts these two learning systems for their ability to classify patients into homogeneous disease and risk groups, as well as their feasibility at achieving the objective of enabling precision dentistry. We conclude that: (a) the World Workshop Model concept of stages and grades works as expected, in that periodontal status appears to be more serious in each successive stage. In addition, the seriousness and the complexity of the disease are greater as the grade increases within each stage. Stages and grades are important for precision dentistry because they consider the risk of future disease and the prognosis, and enable practitioners to use more signs, symptoms, and other associated factors when placing a patient in a diagnostic category; (b) the assignment of stages and grades using unsupervised learning systems is superior to using supervised learning systems for the prediction of 10-year tooth loss and 3-year attachment loss progression. In addition, the unsupervised learning approach (Periodontal Profile Class stages) results in stronger associations between the periodontal phenotypes and systemic diseases and conditions (prevalent diabetes, C-reactive protein, and incident stroke). This probably occurs because an unsupervised learning model produces more data-driven, mutually exclusive, homogeneous groups than a supervised learning model.     

Perceived sources of stress among Greek dental students

The goals of this study were to identify sources of stress in dental education and to explore the role of year of study and gender on perceived stressors. Five hundred and seventy-one undergraduates, officially registered at the University of Athens School of Dentistry, participated in the survey by completing a thirty-item modified version of the Dental Environment Stress Questionnaire. Assigned workload, performance pressure, and self-efficacy beliefs constituted the most stress-provoking factors. Gender differences were found in most of the perceived stressors, whereas stress intensity greatly differed by year of study. Multivariate analysis suggested that, irrespective of gender, fourth-year and graduating students were less concerned about class work overload, clinical training difficulties, and course failing, but were significantly more insecure about their professional future. Entry-level students appeared to be the most concerned about the lack of time for relaxation. However, they were the least stressed about completing graduation requirements compared with the rest of their peers. Possible strategies for reducing stress in Greek dental education are considered in the light of these findings.     

Phototoxic damage to sebaceous glands and hair follicles of mice after systemic administration of 5-aminolevulinic acid correlates with localized protoporphyrin IX fluorescence.

The skin of albino mice given 5-aminolevulinic acid (ALA) by intraperitoneal injection rapidly developed the characteristic red fluorescence of protoporphyrin IX. Fluorescence microscopy of frozen tissue sections revealed intense red fluorescence within the sebaceous glands and a much weaker fluorescence within the epidermis and hair follicles. Little or no fluorescence was detected in the dermis, blood vessels, or cartilage of the ear. Light microscopy of skin taken at intervals after whole-body exposure of ALA-injected mice to photoactivating light revealed destruction of sebaceous cells, focal epidermal necrosis with a transient acute inflammation, and diffuse reactive changes in the keratinocytes. The dermis showed transient secondary edema and inflammation. The location and severity of the phototoxic damage correlated well with the location and intensity of the red fluorescence. The light-exposed skin appeared to recover completely except for a persistent reduction in the number of hair follicles.     

The building blocks of precision oral health in early childhood: the ZOE 2.0 study

Improving children's oral health is a long-standing area of priority and sustained efforts by many stakeholders. Despite these efforts, dental caries, particularly early childhood caries (ECC), persists as a clinical and dental public health problem with multilevel consequences. Despite recent successes in the non-restorative management of dental caries, remarkably little has been done in the domain of ECC prevention. There is promise and expectation that meaningful improvements in early childhood oral health and ECC prevention can be made via the advent of precision medicine in the oral health domain. We posit that precision dentistry, including genomic influences, may be best examined in the context of well-characterized communities (versus convenience clinical samples) and the impact of contextual factors including geography and social disadvantage may be explainable via mechanistic (i.e., biological) research. This notion is aligned with the population approach in precision medicine, which calls for the latter to be predictive, preventive, personalized, and participatory. The article highlights research directions that must be developed for precision dentistry and precision dental public health to be realized. In this context, we describe the rationale, activities, and early insights gained from the ZOE 2.0 study – a large-scale, community-based, genetic epidemiologic study of early childhood oral health. We anticipate that this long-term research program will illuminate foundational domains for the advancement of precision dentistry and precision dental public health. Ultimately, this new knowledge can help catalyze the development of effective preventive and therapeutic modalities via actions at the policy, community, family, and person level.     

The Interface Between Undergraduate and Graduate Education

The aim of this presentation was to provide a stimulus for discussion regarding graduate programmes for clinical disciplines because many countries and organisations are in the process of establishing, improving or harmonising their standards concerning these educational activities. Various aspects of graduate programmes for clinical disciplines were discussed including curricula, degrees/diplomas, structure of clinical education, teacher/student interaction models, research activities and assessment criteria/methods. The presentation gave emphasis to the European experience, but similarities and differences in comparison to the US models were also discussed.