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 caused by trauma such as biting your cheek, jabbing your gum with your toothbrush or even overzealous tooth cleaning. The following can also play a role in developing canker sores: A dental or orthodontic appliance rubbing against the cheek. Genetics.