Dental and Oral Biology

Smoking is a major risk factor for periodontal disease. Research indicates that smokers are significantly more likely to lose teeth than non-smokers, with a pack-a-day habit roughly correlating to the loss of two teeth per decade.

Teeth are unique because enamel contains no living cells and cannot regenerate once damaged. While some body structures like hair shafts and nail visible portions also don't repair, teeth are notably the only organ that truly cannot heal itself.

Teeth are unique because enamel contains no living cells and cannot regenerate once damaged. While some body structures like hair shafts and nail visible portions also don't repair, teeth are notably the only organ that truly cannot heal itself.

The crown is the visible portion of the tooth that extends above the gum line. The root anchors the tooth below the gums in the jawbone, while the pulp and root canal are internal structures within the tooth.

To solve this question, the user needs to know about the composition of teeth and the different layers of it.

The outermost layer of the teeth is called the enamel. Enamel is a hard, tough, and shiny substance that covers the outer part of the teeth.

Now, let's go through each option and explain why it is right or wrong:

A. Wax: This option is incorrect because wax does not cover the outer part of the teeth. Wax is a sticky substance that is used for various purposes such as making candles, sealing envelopes, or polishing furniture.

B. Diamond: This option is incorrect because diamonds do not cover the outer part of the teeth. Diamonds are a precious stone that is used for making jewelry and cutting tools.

C. Keratin: This option is incorrect because keratin does not cover the outer part of the teeth. Keratin is a fibrous protein that is found in hair, nails, and skin.

D. Enamel: This option is correct. Enamel is a hard, tough, and shiny substance that covers the outer part of the teeth, protecting it from damage and decay.

Therefore, the answer is: D. Enamel

Teething and diarrhoea are coincidental events in infancy, not causally related. The belief that teething causes diarrhoea is a myth - infections or dietary changes cause diarrhoea, not tooth eruption.

A dental abscess is a serious infection caused by severe tooth decay, where bacteria infect the dental pulp and create a pocket of pus. Symptoms include severe pain, swelling, and sometimes fever. Root canal therapy or extraction is often required to treat it. Bonding is cosmetic repair, a bridge replaces missing teeth, and filling treats decay before infection sets in.

Bleaching is the dental procedure of applying hydrogen peroxide or carbamide peroxide solution to whiten discolored or stained teeth. The peroxide penetrates enamel and breaks down stains through oxidation. Scaling removes tartar, periodontitis is gum disease, and filling restores decayed tooth structure but doesn't change color.

Bonding is the dental procedure of attaching tooth-colored composite resin materials to stained or damaged teeth to restore or improve their appearance. The resin is applied, shaped, and hardened with a special light. Filling uses amalgam or composite but focuses on function, an impacted tooth is one that hasn't emerged properly, and periodontitis is gum disease.

A crown is a prosthetic covering that completely encircles a damaged or decayed tooth to restore its shape, size, strength, and appearance. Bleaching is a whitening procedure, abscess is an infection, and endodontist is a dental specialist - none of which match the definition of an artificial tooth covering.

Dentures are removable prosthetic devices that replace missing teeth. Partial dentures can be removed and are attached to remaining natural teeth, while full dentures replace entire arches. Bonding is adhesive tooth-colored material, filling is for cavities, and root canal treats pulp damage.

A filling is the material placed in a prepared cavity to restore tooth structure. The description exactly matches dental filling materials, which can be amalgam (metal mixture), composite (plastic), porcelain, or gold. Bridges replace missing teeth, crowns cover teeth, and periodontitis is gum disease.

An impacted tooth is one that fails to erupt properly and remains trapped beneath the gum tissue, often causing pain and requiring extraction. Bridges replace missing teeth, periodontitis is gum disease, and orthodontics refers to tooth alignment - none describe an unexposed, confined tooth.

Orthodontic treatment uses braces, aligners, and other devices to gradually reposition misaligned teeth. An impacted tooth is unerupted, a bridge replaces missing teeth, and periodontitis is gum inflammation - none involve corrective positioning devices.