Oropharyngeal squamous cell carcinomas (OSCCs) are increasing in incidence and are associated with considerable morbidity and mortality. Recognised risk factors include sexual behaviour, high risk oral HPV infection and poor oral hygiene. Large proportions of the general population attend dental clinics on a regular basis, where they routinely undergo assessment of their oral hygiene. We set out to investigate whether risk assessment for OPSCC could be undertaken in two general dental clinics.
Patients aged ≥18 years attending two general dental clinics in Sydney, Australia were invited to participate in the study. Participants completed demographic and behavioural questionnaires. Oral Hygiene Index (OHI) was recorded by examining six tooth surfaces separately for debris and calculus status. A score ranging from 0 to 3 for each examined surface was recorded, and the OHI calculated using a formula. 10ml saline oral rinses were obtained prior to their booked dental procedure, which were subsequently tested for Human Beta Globin gene (HBG) and HPV genotypes by PCR.
Three hundred and nine dental patients were approached and 302 (97.7%) agreed to participate. Two (0.7%) people were excluded because of inadequate sampling. The mean age of the 300 remaining participants was 48 years (range 19-87), of whom 131 (43.6%) were male, 12 (9.2%) of men reported a history of sexually transmitted infections and one (0.3%) was known to be HIV infected.
HBG was detected in all samples and HPV genotypes in six samples (2.0%), all men. The HPV genotypes were one each of types 16, 66, 51, 35, 58 in five participants, and 18 combined with 52 in one participant. Eighty nine (67.9%) of men reported oral sex practices. Four (4.5%) of these 89 had oral HPV detected (all exclusively with female partners). Five (2.1%) of the 233 participants with an OHI of ≤ 1 (good oral hygiene), compared to one (4.3%) of the 23 with an OHI ≥ 2 (poor oral hygiene) had at least one HPV genotype detected.
A large majority of patients approached at the general dental clinics agreed to participate. The clinical relationship between the dental practitioner and patients enabled the collection of potentially sensitive demographic and behavioural data. Oral hygiene assessment could be performed accurately and professionally. Oral rinse sampling was well tolerated by participants, and satisfactory samples were obtained. Dental surgeries may be ideally placed to undertake risk evaluation for OPSCC. Larger trials are needed to evaluate this method further, and determine correlations between persistent oral HPV infection and risk.
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