Commute 45 to 59 min. 7.20%. Commute greater than 60 min.
1 Oral Ulcers: Usually, an ulcer is referred to as an open wound which is formed inside the mouth and this occurs due to the invasion of micro organisms. 2  Sometimes, blood blisters are caused due to the skin infections caused as a side effect of medications. 3  Ulcers are of two types they are: Canker sores and Cold sores.
Blood blisters in the mouth could be due to canker sores, also known as aphthous ulcers and due to cold sores. The cause of canker sores is still not known though they can be very painful and cause great discomfort to the person.