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Other Oral Health Topics


Tooth Discolouration

Brown and black stains on the surface of teeth Stains were removed after professional cleaning.
Extrinsic Stain, Before Treatment - The tooth surface was stained by food colour. Extrinsic Stain, After Treatment
A tooth appears greyish-black in colour because of non-vital pulp. The tooth colour was whitened after appropriate dental treatment.
Intrinsic stain, Before Treatment.
The 'dead' pulp released some substances into dentine to stain it greyish black.
Intrinsic stain, After Treatment.
Both intrinsic and extrinsic stains can lead to tooth discolouration. Intrinsic stains may be due to tetracycline, excessive fluoride intake, pulp degeneration after tooth trauma and the presence of metallic restorative materials such as silver amalgam. Appropriate treatments such as aesthetic restorations and bleaching help in improving appearance.

Extrinsic stains may be due to coffee, tea, traditional Chinese medicine or tobacco products. Professional cleaning can remove extrinsic stains.

Gum Bleeding

Dental plaque accumulating at gum margin leads to gingival inflammation with swelling and bleeding.
Bleeding Gums

Poor oral hygiene is the most common cause for gum bleeding. Bacterial toxins from plaque accumulate at gum margin lead to inflammation with swelling and bleeding while brushing. Scrupulous attention should be paid to oral hygiene. Once oral hygiene improves, bleeding will subside and gum will become healthy again.

Tooth Trauma

Crown fracture due to trauma. Tooth dislocation due to trauma.
Crown Fracture Tooth Displacement
Tooth trauma is common when a child grows up and becomes active. Contact sports may lead to teeth injury. You should consult your dentist when there is an obvious tooth crack or fracture and, if possible, bring along the fragment of your fracture tooth with you. Root or bone injury may be detected by professional dental staff only. Participants of the School Dental Care Service can seek emergency treatments from their designated school dental clinics.

Tooth Knocked Out

If a tooth avulsed (knocked out of the tooth socket), adopt the following procedures: An upper incisor was avulsed due to traumaAn avulsed upper central incisor.
Pick up the avulsed tooth by holding the crown without touching the root.
Stay calm and pick up the avulsed tooth by its crown without touching the root.
Gently rinse off the dirt on the tooth surface with clean water.
Do not attempt to scrub the tooth. Gently rinse off any obvious dirt on the root surface with clean water.
Insert the tooth back into the socket.
Put the tooth back into the socket if you can, or place the tooth in the mouth between the cheek and gum,
Immerse the tooth in a container filled with fresh milk
or keep the tooth in a pack of fresh milk.
Seek treatment from dentist immediately
Immediately see a dentist for treatment at any nearby school dental clinic during office hours, or a nearby private dental clinic or the Accident and Emergency Department of a nearby public hospital outside office hours. The sooner the tooth is replanted, the higher is the chance of success.

Leong's Premolar

A Leong's premolar differs from an ordinary premolar by having some tooth structures projecting from its chewing surface. These structures are very fragile and easily fractured. If they are not properly treated after fracture, the pulp may die due to infection and may lead to dental abscess formation. In order to prevent this from happening, preventive treatment is advocated at our School Dental Care Service. According to the tooth condition, either reinforcement of the fragile structure or removal of the structure then restoration of the defect can be done.
A Leong’s premolar has a projected and fragile portion of tooth structure.  If the projected structure has fractured, there will be chances for bacterial infection.  The pulp may become necrotic or may even result in dental abscess.

Aphthous Ulcer

An aphthous ulcer is found on the oral mucosa.
Aphthous Ulcer
Aphthous ulcer is a kind of ulcer found on oral mucosa. At present, medical research is still unable to find out the cause, and there is still not effective way to prevent its occurrence. Fortunately an aphthous ulcer usually heals by itself within 2 to 3 weeks. You may find that rinsing your mouth with warm saline can help in easing the pain. You may also get medication from dentist or doctor to put on the ulcer for lessening the pain. If ulcer persists for more than 1 month, you should see a doctor to find out whether it is related to other diseases.