Reversible<unk> 
Duration of pain is short (seconds)
Associated with noxious stimuli (usually cold or heat, can also be elicited by sweat and sour)
Irreversible<unk> 
Duration of pain is long (hours) and intense
Associated with noxious stimuli or may occur spontaneously
Duration of pain is short (seconds)
Associated with noxious stimuli (usually cold or heat, can also be elicited by sweat and sour)
Duration of pain is long (hours) and intense
Associated with noxious stimuli or may occur spontaneously
Pulpitis
Dental fracture
Pleuritis
Dental subluxation
Croup
Dental avulsion
Laryngitis
Bleeding dental socket