a. Types and causes
A mouth ulcer is a break in the lining of the mouth that uncovers the sensitive tissue underneath.  All mouth ulcers look much the same, but they vary considerably in cause and seriousness.  The two most common and painful types of ulcers are aphthous ulcers, which tend to occur when you are under stress, feeling run-down or ill, and traumatic ulcers, which result from an injury to the lining of your mouth. Such an injury may be caused by a toothbrush, a rough denture, or hot food. Some mouth ulcers are caused by viral infection. A virus that commonly causes mouth ulcers is the herpes simplex. This virus causes blisters which eventually turn into ulcers. Rarely, an ulcer may be the first sign of a tumor of the mouth, or a more generalized disease such as leukemia or anemia. Mouth ulcers are extremely common. Apthous ulcers occur most often in adolescents and young adults, and more often in women (especially just before a menstrual period).

b. Oral Signs and Symptoms
You usually first become aware of an ulcer when you eat something spicy or acidic that makes it sting. All ulcers look much the same. You can usually see them in the mirror as pale yellow spots with red borders. Apthous ulcers are small measuring 2 to 3mm (1/10th inch) across. They usually appear in clusters on the sides of the tongue or gums and last for 3 to 4 days. A traumatic ulcer is usually larger and lasts for a week or more. When a traumatic ulcer is caused by a rough tooth or denture, it will not heal until the cause of the irritation is removed.

c.  Treatment
The vast majority of mouth ulcers do not indicate any major health problem and usually heal by themselves. But if an ulcer fails to heal within 2 weeks or if ulcers keep recurring, then see your physician or dentist to find out if the ulcers are being caused by a more serious underlying condition. Your physician may want you to have blood test taken and you may also have to undergo a biopsy of the ulcer. In this procedure part of the ulcer is removed under a local anesthetic, so that it can be examined. The results of these tests will show whether the ulcer signifies a serious disorder, which will then be dealt with as necessary.

d. Self-help
You can buy various nonprescription topical applications and lozenges that numb and protect the exposed tissue in an ulcer. These preparations relieve the pain and may help the ulcer to heal. Antiseptic mouthwashes or rinsing your mouth with warm salt-water may also help. To minimize discomfort avoid eating spices (such as chili and pepper) or acidic foods (grapefruits and oranges, for example). The ulcer will also be sensitive to hot foods or drinks.

To read about an exercise called ‘Dr. Mansky’s Simple 5 Minute Dental Anxiety Cure’ click dental anxiety_cure.  For a long explanation about the causes of dental anxiety and how we treat it click eliminate_dental_anxiety.  The approach we use is fast, simple and very successful.  It is not uncommon for a person to say after 5 -10 minutes “Is that what kept me away from the dentist for so long?  I’m ready.  Let’s get started.”

There are a few reasons a filling may fall out. 
      a. A filling may crack if excessive pressure is placed on it from a heavy bite,
      b. Fillings can weaken over time and break.
      c. Some new filling materials are a lot stronger than even 10 years ago. 
      d. Dental decay softens tooth structure weakening the support for the filling and the filling can break. 

a. There are a number of reasons for this to happen.  A cavity between teeth cause by tooth decay, an open space between fillings, crowns that do not fit properly or spaces caused by shifting teeth near a missing tooth.  Gum infection can also result in areas where food can catch.

b. Treatment can be a new filling, crown or onlay or treatment of gum disease.  If the spaces are natural because of how your teeth erupted, orthodontic treatment may be the best solution.