Teeth Whitening - More of a Hope Than Hype

• Chromogenic compounds (foods, beverages, other consumables)
  

  The dark compounds found in products we consume (coffee, tea, cola, wine, tobacco, etc.) can cause yellow, brown or burnt orange tooth staining.

  In most cases the discoloration is generalized, meaning, that it tends to affect all teeth and tooth areas somewhat equally.
  

• Age-related darkening
  

  It's normal for a person's teeth to gradually take on a generalized yellow or brown coloration as years and decades pass.
  

• Genetic factors 
  

  The baseline color of a person's teeth may naturally be more yellow, brown or gray, or relatively lighter or darker, than other people's due to their particular genetic make-up.
  

• Tetracycline (and related antibiotics)  

  Tetracycline tooth stains can be yellow-brown or possiblyblue-grey in color. The pattern of the staining can be quite varied. It can appear as isolated areas or lines but more likely involves broad bands or whole-tooth discoloration. Characteristically, multiple teeth are affected.

• Fluoride (fluorosis) 
  

  Fluorosis staining results in chalky-white or possibly brown spots, patches or lines dispersed across a tooth's surface. The blemishes may show evidence of surface pitting. Typically, multiple teeth are involved.
  

• Internal tooth changes / Root canal treatment 
  

  Generalized brown or gray discoloration can be caused by changes that have occurred within a tooth's nerve space. The process can be triggered by events such as trauma, or needing to or having had root canal treatment. Only those teeth directly affected by the event (frequently just a single tooth) are affected.
  

• Tooth decay 
  

  The early stages of cavity development result in the formation of white spots or patches on enamel tooth surfaces. The affected area will loose its glossy sheen and on close inspection may show evidence of surface damage.

  As the decay process advances, the involved area typically takes on a tan, brown or black coloration. The lesion itself may first become noticeable as a small dark spot or blemish that grows in size over time (typically months to years), frequently involving obvious tooth destruction.
  

• Deteriorated dental restorations 
  

  Deteriorated or failed dental work can result in areas of yellow, brown, gray or even black tooth discoloration. A dark spot, line or underlying halo effect may develop at the edges of the failing restoration. Areas of associated tooth decay may be visible.
  

• Surface staining / Poor oral hygiene 
  

  The accumulation of debris on the surface of teeth can result in white, yellow, tan, brown, black, or possibly even green discolorations. The staining is typically most intense in those areas that are hardest to keep clean, such as near the gum line.

Tooth whitening is either restoration of natural tooth shade or whitening beyond natural tooth shade.

Teeth whitening in case of stains caused by extrinsic agents, a simple scaling and polishing in one or more sittings might be sufficient. But incase of intrinsic stains like flurosis and tetracycline staining, we need to choose advanced methods of teeth whitening.

Scaling  otherwise known as conventional periodontal therapy, non-surgical periodontal therapy, or deep cleaning, is the process of removing or eliminating the etiologic agents – dental plaque, its products, and calculus – which cause teeth discoloration, halitosis, inflammation of gums & periodontal disease.

Polishing may be done to remove stains and surface irregularities.

Bleaching include in-office bleaching (applied by a dental professional), and treatments which the individual carries out at home (either supplied by a dental professional or available over the counter).

Bleaching solutions generally contain hydrogen peroxide or carbamide peroxide, which bleaches the tooth enamel to change its color. Off-the-shelf products typically rely on a carbamide peroxide solution varying in concentration from 10% to 44%. Bleaching solutions may be applied directly to the teeth, embedded in a plastic strip that is placed on the teeth or use a gel held in place by a mouthguard. Carbamide peroxide reacts with water to form hydrogen peroxide. Carbamide peroxide has about a third of the strength of hydrogen peroxide. This means that a 15% solution of carbamide peroxide is the rough equivalent of a 5% solution of hydrogen peroxide. The peroxide oxidizing agent penetrates the porosities in the rod-like crystal structure of enamel and breaks down stain deposits in the dentin.

A power bleaching treatment typically involves isolation of soft tissue with a resin-based, light-curable barrier, application of a professional dental-grade hydrogen peroxide whitening gel (25-38% hydrogen peroxide), and exposure to the light source for 6–15 minutes.

Toothpastes (dentifrices) which are advertised as "whitening" rarely contain carbamide peroxide, hydrogen peroxide or any other bleaching agent. Rather, they are abrasive  intended to remove surface stains from the tooth surface.  Unlike bleaches, whitening toothpaste does not alter the intrinsic color of teeth. Excessive or long term use of abrasive toothpastes will cause dental abrasion, thinning the enamel layer and slowly darkening the appearance of the tooth as the dentin layer becomes more noticeable.

Laminates and Veneers are other options  of teeth whitening by placing very thin veneers on prepared tooth surface. If properly prepared and maintained, they last for long time.

With excellent brushing habits and professional cleanings, you can maintain your bright smile. Still, stains can return over time, with habits like coffee drinking and smoking. Visit your dentist's office for regular checkups.