
Why Teeth Turn Yellow: Surface Stain or Dentine Showing
Teeth turn yellow for two reasons: pigment from coffee, tea or tobacco settling on the enamel, or thinning enamel letting yellow dentin show through.
Clinical experience, misunderstood concepts and frequently asked questions. Notes from many years of practice.

Teeth turn yellow for two reasons: pigment from coffee, tea or tobacco settling on the enamel, or thinning enamel letting yellow dentin show through.

A laminate veneer is a 0.2 to 0.5 mm ceramic or composite shell bonded to the front of a tooth with little or no enamel removed; a crown runs 1.5 to 2.0 mm.

After wisdom teeth removal, eat cool, soft, spoonable food and skip the straw: liquids on day 1, soft foods from day 2; most eat normally by weeks 3 to 4.

Across 29 studies covering 2,300 resin-bonded bridges, survival was 91.4% at five years and 82.9% at ten, with de-bonding the leading complication at 15%. A Maryland bridge needs little or no drilling.

Memory, attention and nerve conduction showed no significant differences even though urinary mercury rose, and composite showed lower longevity than amalgam.

Freddie Mercury had four extra teeth in his upper jaw. Extra teeth affect 0 to 3 percent of people; what they did to his bite, and why he kept them.

Across 53 studies, Class I made up 74.7 percent of permanent dentition cases, Class II 19.56 percent and Class III 5.93 percent. Which patterns cause trouble?

Botulinum toxin A cut gingival display by a mean 2.51 mm at two weeks, while lip repositioning surgery reduced it by 2.87 mm. Which cause needs which?

Crooked teeth are teeth that are turned, crowded, spaced or in crossbite. Fixed braces averaged 19.9 months across 22 studies; aligners suit milder cases.