This study is a retrospective comparative evaluation of six main periodontal pathogens and total bacterial load in chronic periodontitis patients affected or not by type 2 diabetes mellitus by polymerase chain reaction analysis.

The aim of this study was to compare prevalence and bacterial load of six main periodontal pathogens among chronic periodontitis patients with and without type 2 diabetes mellitus. Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans genotypes were also investigated.

The recruitment for the study sample was performed analysing the medical records of adult patients with chronic periodontitis visited between 2010 and 2016. Eligible patients were subdivided in two balanced groups on the basis of the presence or absence of type 2 diabetes mellitus at the time of the microbiological test.

For each subject, the following data have been collected: age, gender, smoking habits, type of metabolic control of diabetes, duration of diabetes, number of missing teeth.

For each subject, four periodontal sites were studied. Probing pocket depth, sites with bleeding on probing, sites with suppuration and microbiological data were evaluated.

An individual matching on the basis of severity and extension of periodontitis was performed by pairing a diabetic patient with another non-diabetic one with the same degree of severity and extension of the periodontal disease.

Microbiological data of subgingival biofilm were analysed and compared for the examined pathogens: Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, Fusobacterium nucleatum, Tannerella forsythia.

Differences in genotypes of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans among diabetic and non-diabetic patients were also evaluated.

Inclusion Criteria:

• diagnosis of chronic periodontitis
• diagnosis of type 2 diabetes mellitus (only in the test group)
• the presence of at least 12 teeth (except for the third molar)
• belonging to caucasian ethnic group
• age greater than 18 years.

Exclusion Criteria:

• pregnant or lactating
• history of systemic antibiotics within 3 months prior to the microbiological testing or anti-inflammatory therapy in the month before the visit
• if they were suffering from any other systemic disease except diabetes mellitus (arthritis, ulcerative colitis, Crohn's disease, osteoporosis or osteopenia, HIV infection, hematologic diseases, neoplastic diseases, cardiovascular diseases or pathologies that could potentially interfere with the periodontitis and/or with diabetes)
• mental disorders
• if they had received periodontal treatment in the 6 months before the microbiological test.

The recruitment for the study sample was performed analysing the medical records of adult patients with chronic periodontitis visited between 2010 and 2016. Eligible patients were subdivided in two balanced groups on the basis of the presence or absence of type 2 diabetes mellitus at the time of the microbiological test.

Data will be available when the research will be published

Data will be available when the research will be published

On request to the main investigator