Risk Factors for Severe Periodontitis in 30 to 40 Year Olds: a Retrospective Study

Periodontitis is one of the most common oral diseases, which is characterized by alveolar bone resorption and destruction. In China, as a major country in the incidence of periodontitis, there is a huge population of patients with severe periodontitis, and the incidence rate is as high as 12.1-16.1% . Previous studies have suggested that the prevalence and severity of periodontal disease increase with age. However, recent articles on meta analysis and related epidemiological investigations suggest that the prevalence of severe periodontitis does not increase with age, and the prevalence of SP remains at about 10% even in the elderly. In order to comprehensively analyze the risk factors of this population, it is inseparable from the analysis of gene polymorphism. At present, it is considered that the main genes that may be related to the severity of periodontitis are IL-1 α-889, rhIL-talk 1 β + 3953, 6-174, 10-597, CD14-260, CD14-159, MMP1-1607 and so on, which may be related to the severity of periodontitis.

Periodontitis is one of the most common oral diseases, which is characterized by alveolar bone resorption and destruction. In 2010, severe periodontitis (severe periodontitis,SP) had become the sixth largest epidemic disease in the world, affecting 10.8% of the global population or 743 million people . In China, as a major country in the incidence of periodontitis, there is a huge population of patients with severe periodontitis, and the incidence rate is as high as 12.1-16.1% . The fourth National Oral Health Epidemiological Survey also found that the oral health of residents aged 35-44 is generally poor , which has become a major obstacle to the implementation of the "Healthy China 2030" strategy. Previous studies have suggested that the prevalence and severity of periodontal disease increase with age . The possible reasons for this phenomenon are as follows.First, the cumulative effect of attachment level and bone loss with age.Second, changes related to the aging process, such as drug intake, decreased immune function, and changes in nutritional status interact with risk factors can increase the susceptibility to periodontitis. However, recent articles on meta analysis and related epidemiological investigations suggest that the prevalence of severe periodontitis does not increase with age, and the prevalence of SP remains at about 10% even in the elderly. In addition, the global meta analysis with large sample size showed that the prevalence of SP increased sharply between 30 and 40 years old, peaked at about 38 years old. This trend of severe periodontitis with age is not consistent with our traditional cognition, and there is no related research to explain this trend. However, it is found that 30-40 years old patients with severe periodontitis account for a large proportion, so it is of great significance to analyze the risk factors of this group and carry out targeted prevention and control. In order to comprehensively analyze the risk factors of this population, it is inseparable from the analysis of gene polymorphism. Studies related to severe periodontitis gene polymorphism are mainly focused on Toll-like receptor (Toll-likereceptors), interleukin (interleukin,IL), immunoglobulin receptor (Immunoglobulinreceptors), formyl peptide receptor (Formylpeptide receptor), vitamin D receptor (VitaminDreceptor, VDR) and matrix metalloproteinases (matrixmetalloproteinase,MMP). At present, it is considered that the main genes that may be related to the severity of periodontitis are IL-1 α-889, rhIL-talk 1 β + 3953, 6-174, 10-597, CD14-260, CD14-159, MMP1-1607 and so on, which may be related to the severity of periodontitis.

Eligibility Criteria:
Inclusion Criteria:

* 1. The patients aged between 30 and 40 years old were diagnosed with severe periodontitis and were treated for the first time, while those in the control group were patients with non-severe periodontitis or healthy people. All the subjects had complete basic information, questionnaire data and clinical examination data. 3. The patient's thinking is clear, there is no barrier to communication, and can cooperate to complete the questionnaire. 4.In addition, the genetic polymorphism test required that the three generations were all Han nationality, with no history of orthodontic treatment, no obvious malocclusion and local stimulating factors, and no Systemic disease (including diabetes, cardiovascular disease, hepatitis, HIV infection, etc.), non-smoking or non-smoking for more than 5 years

Exclusion Criteria:

* 1. Patients suspected to be invasive periodontitis, the plaque level and the degree of periodontal destruction are disproportionate. 2. Systemic diseases (including diabetes, cardiovascular disease, hepatitis, HIV infection, etc.) 3. Pregnant women, women who are pregnant, lactating or mentally ill. 4.Those who are taking known drugs that affect periodontal tissue or have a history of antibacterial treatment within 6 months. 5.Those who have a history of periodontal treatment within 6 months are excluded. 6.In addition, testing for genetic polymorphism required the exclusion of malignancies or those who had undergone radiotherapy or chemotherapy