This fact is from Systemic Disease Manifestations in Oral Medicine & Radiology. It is a commonly tested concept in NEET MDS examinations. Understanding this fact is crucial for answering MCQs correctly.
Diabetes = periodontal disease delayed healing
Pernicious anemia = glossitis = Hunters glossitis
Addisons disease = oral pigmentation = bronze skin
Sjogrens syndrome = dry mouth xerostomia + dry eyes keratoconjunctivitis sicca
Crohns disease = cobblestone mucosa lip swelling.