The Characterisation of Therapeutic Radiation-induced Dental Caries; the Histopathological, Ultrastructural and Microbial Changes Affecting Its Prevention and Treatment

Head and neck cancer represent 4-5% of all of cancer diagnosed in the UK, the first choice of treatment it is Radiotherapy (RT). RT is known to produce a wide range of oral side effects such as hypo-salivation, caries, xerostomia, mucositis and osteoradionecrosis.

Hypo-salivation may lead to a shift in diversity of the bacterial population altering oral homeostasis. RT may also cause a variation in saliva protein composition which can affect its rheological properties and host defence increasing the possibility of caries development. Additionally, the effects of RT on the organic and inorganic structure/ composition of teeth and the possible relation with caries risk have not been investigated so far.

Mucositis is another frequent oral complication of RT and it is estimated that more than 80% of the treated patients will develop this condition.

Longitudinal studies assessing all these conditions before and after cancer treatment have not been reported in literature to date.

Therefore, the main objective of the proposed study is to assess the chemical composition of the dentine matrix, the variations in salivary proteins and in oral microbiome occurring in Head & Neck cancer patients undergoing RT. These data will be collected and a complete oral assessment with 18 month follow up will be performed. All these data will be computed to demonstrate the associations between RT and caries risk to demonstrate possible mechanistic causes.