In stochastic processes, chaos theory and time series analysis, detrended fluctuation analysis (DFA) is a method for determining the statistical self-affinity of a signal.
Sore throats caused by tonsillitis or streptococcus may trigger a canker sore even after the initial throat condition has subsided. Also known as an aphthous ulcer, canker sores are painful and unsightly, but they are not contagious.
Canker sores can be very painful! The exact cause of canker sores is not entirely certain, although several different factors including stress, certain spicy/acidic foods, or vitamin deficiencies can be associated with them. They are also associated with some autoimmune or gastrointestinal conditions such as Crohn's disease or celiac disease. Canker sores typically resolve within a week or so, although aggravating factors such as spicy foods or mechanical trauma can make them take longer to heal. The fact that your canker sores have persisted for over 3 weeks is an indication that you should return for evaluation with either your dentist or your oral surgeon.