Recent studies have found that persistent periodontal disease (including gingivitis and periodontitis) and human papillomavirus (HPV) work together to promote the development of head and neck cancer. Authoritative data released by the National Cancer Institute confirms that HPV is now recognized as an important causative factor in the development of head and neck cancer. In a recent study conducted by Professor Tezal of New York University, researchers analyzed data from 124 patients with a definite diagnosis of lentigo squamosa and found that more than 40% of these 124 patients had HPV infection. These HPV-infected patients with head and neck cancer were more likely to develop periodontitis than patients without HPV infection. Professor Tezal then pointed out that periodontal disease is a relatively easy to detect oral disease, and that doctors finding periodontal disease can predict that the patient may have a higher risk of HPV infection. In addition, the chronic inflammation of periodontal disease is critical to the pathogenic process of HPV infection causing head and neck squamous carcinoma. Therefore, routine oral examination to reduce chronic inflammation in the oral cavity, especially periodontal disease, is a simple and easy way to reduce HPV infection and prevent head and neck squamous carcinoma.