YOu should do a PubMed search for this. You don't need people's ideas – that's pretty dependent on who notices the question. You need to review the literature.
Quite variable prevalence, depends on type 1 or type 2 diabetes, self-care of oral cavity/dental care, age of patient, quality of control, diet, cigarette smoking status and other dental factors like crowding, alignment etc.
Diabetes mellitus is recognized as an important risk factor for more severe and progressive periodontitis, infection or lesions resulting in the destruction of tissues and supporting bone that form the attachment around the tooth. Periodontal disease has been reported as the sixth complication of diabetes mellitus, along with neuropathy, nephropathy, retinopathy, and micro- and macrovascular diseases.