Effects of laser photobiomodulation in the management of oral lichen planus: a literature review.

Objectives: This review aims to understand whether Photobio-modulation (PBM) therapy is a valid aid in the management of Oral Lichen Planus (OLP) and its symptoms. Moreover, an analysis to determine whether it is a valid replacement for conventional therapies and whether standardized protocols can be used in PBM sessions or whether these should be changed depending on the type of injury has been made. Finally, an evaluation to determine whether PBM may induce transformation of dysplastic oral keratinocytes into squamous cell carcinoma has been made. Materials and Methods: Searches were conducted on two search databases for relevant publications released between 1992 and 2019. The databases used were: Pubmed "Medline", and Google Scholar. Forty-four articles complied with the inclusion criteria and were included for quality assessment and data extraction. Results: All the studies reported positive effects of PBM; how-ever, there was wide heterogeneity in the laser parameters used in the management of the OLP. The effective dose ranges from 2 to 3 J/cm2, in order to see the desired biological effects. Conclusions: PBM is useful in controlling algal sensation and can be used in cases of OLP lesions that are not responsive to conventional therapies or when corticosteroid doses are too high for the patient, resulting in possible side effects. Standardized biostimulation protocols with further scientific insights are therefore required.

Frequent detection of high human papillomavirus DNA loads in oral potentially malignant disorders.

Human papillomavirus (HPV) is estimated to be the cause of 40--80% of the squamous cell carcinoma of the oropharynx but only of a small fraction of the oral cavity cancers. The prevalence of oral HPV infection has significantly increased in the last decade, raising concerns about the role of HPV in progression of oral potentially malignant disorders (OPMD) toward squamous cell carcinomas. We sought to study HPV infection in patients with oral lesions, and in control individuals, using non-invasive and site-specific oral brushing and sensitive molecular methods. HPV DNA positivity and viral loads were evaluated in relation to patient data and clinical diagnosis. We enrolled 116 individuals attending Dental Clinics: 62 patients with benign oral lesions (e.g. fibromas, papillomatosis, ulcers) or OPMD (e.g. lichen, leukoplakia) and 54 controls. Oral cells were collected with Cytobrush and HPV-DNA was detected with quantitative real-time PCR for the more common high-risk (HR) and low-risk (LR) genotypes. HPV detection rate, percentage of HR HPVs and HPV-DNA loads (namely HPV16 and in particular, HPV18) were significantly higher in patients than in controls. Lichen planus cases had the highest HPV-positive rate (75.0%), hairy leukoplakia the lowest (33.3%). This study detected unexpectedly high rates of HPV infection in cells of the oral mucosa. The elevated HR HPV loads found in OPMD suggest the effectiveness of quantitative PCR in testing oral lesions. Prospective studies are needed to establish whether elevated viral loads represent a clinically useful marker of the risk of malignant progression.