Tooth discoloration, a common dental concern, refers to changes in the color of teeth, deviating from their natural hue. Institutions like US Food and Drug Administration have helped improve our understanding of various tooth discoloration causes, which significantly impacts both oral health and aesthetics.
Naturally, teeth exhibit shades ranging from light yellow to grayish-white. Variations in color are normal, yet certain factors can lead to more pronounced and often undesirable changes.
If you prefer, you can also watch this video where a dental hygienist explains common causes of teeth stain:
Extrinsic Tooth Discoloration Causes
Extrinsic causes of tooth discoloration are factors external to the tooth structure, typically affecting the enamel surface. These causes are often related to lifestyle choices and habits.
Foods and Beverages
Various foods and drinks are notorious for staining teeth. Dark-colored foods such as berries and sauces like soy sauce can leave stains. Beverages including coffee, tea, and red wine are especially well-known for their staining capabilities due to intense color pigments called chromogens that adhere to the tooth enamel.
Tobacco Use
Tobacco products, both smoked and chewed, contain tar and nicotine, which are major contributors to tooth discoloration. Nicotine, when mixed with oxygen, turns yellowish and embeds into the tooth enamel, leading to stubborn stains.
Dental Hygiene
Inadequate oral hygiene practices can lead to surface stains on teeth. Ineffective brushing and flossing fail to remove plaque and food particles, leading to discoloration. Additionally, irregular dental check-ups mean professional cleanings are missed, allowing surface stains to accumulate and harden over time.
Intrinsic Tooth Discoloration Causes
Intrinsic causes of tooth discoloration originate from within the tooth, affecting the underlying dentin or the enamel’s internal structure. These factors are often less preventable than extrinsic causes and may require different treatment approaches.
Medications
The National Center for Biotechnology Information (NCBI) found that certain medications cause tooth discoloration, particularly when taken during teeth development. Antibiotics like tetracycline and doxycycline can lead to a yellow or gray discoloration if used during childhood.
Other medicines, including antihistamines, antipsychotic drugs, and medications for high blood pressure, can also contribute to tooth color changes. A 2019 study described how a 40-year-old woman developed sudden-onset tooth discoloration during her rosacea treatment, which included oral doxycycline.1
An analysis of the US Food and Drug Administration Adverse Event Reporting System analyzed 625 adverse event (AE) reports involving 25 drugs with positive risk signals for tooth discoloration. This study revealed that certain drugs are significantly associated with tooth discoloration, primarily in patients aged 45–64 and those aged 18 or younger.2
Dental Materials
Some dental materials, particularly older amalgam restorations containing silver sulfide, can cause a gray-black coloration of the surrounding tooth structure. This is due to the material’s components leaching into the tooth.
Aging
As people age, enamel naturally wears down, becoming thinner and more transparent, revealing the darker dentin beneath. Additionally, the dentin itself may change over time, becoming darker or more yellow.
Saliva
A 2017 PubMed study involving 500 patients fond that in addition to diet, the amount and properties of your saliva also can lead to tooth stains.
If for example you find that you often have a dry mouth, this indicates that your saliva levels are lower. Saliva helps break remove and break down food debris.3 If there’s an insufficient saliva flow, food particles remain in your mouth longer, and thus can also work on your teeth longer, potentially increasing discoloration from extrinsic factors.
Genetic Factors
Genetic variations can influence the thickness and composition of enamel and dentin. Some individuals may have naturally thinner enamel or darker dentin, predisposing them to the appearance of discolored teeth.
Trauma or Disease
Physical trauma to teeth, especially during their development, can lead to discoloration. This can be due to damage to the developing tooth or internal bleeding within the tooth structure. Certain diseases, particularly those affecting enamel and dentin formation, can also cause intrinsic discoloration. This includes conditions present at birth or those developed during tooth formation.
Environmental Factors
Environmental factors contributing to tooth discoloration include elements and conditions external to the individual’s control, often relating to their living environment or exposure to certain chemicals.
Excessive Fluoride
Excessive exposure to fluoride, especially during the developmental stages of teeth, can lead to a condition known as fluorosis. This results in white streaks or spots on the teeth, and in severe cases, can cause brown markings. Sources of fluoride include drinking water, certain dental products, and fluoride supplements.
Environmental Pollution
Pollutants in the environment can also affect tooth color. For example, high levels of iron in water supplies can lead to a brownish discoloration of teeth. Other minerals and metals present in polluted air or water, such as copper or nickel, can similarly affect tooth color over time.
The pollution problem in Bangkok for example has been getting worse in recent years during the winter season. Even air pollution can lead to tooth discoloration, because particles in the air attach to tooth enamel and erode it, leading to discoloration. (Which might be one reason why teeth whitening has become so popular with Bangkok residents.)
These environmental factors highlight the importance of considering the broader context in which tooth discoloration occurs, emphasizing the need for comprehensive dental assessments to determine the underlying causes.
Conclusion
In summarizing the causes of tooth discoloration, it becomes evident that this common dental issue arises from a variety of sources:
- Extrinsic factors such as diet, tobacco use, and dental hygiene significantly contribute to surface stains on teeth.
- Intrinsic factors, including medications, aging, genetics, and trauma, affect the internal structure and color of teeth.
- Environmental elements like excessive fluoride and pollution also play roles in altering tooth coloration.
Recognizing these diverse causes is vital for effective prevention and management. While some factors, like genetics and aging, are beyond control, many causes of tooth discoloration can be mitigated through
- lifestyle changes,
- diligent oral hygiene,
- and professional dental care.
Regular dental visits are essential not only for maintaining oral health but also for monitoring and addressing any changes in tooth color.
Ultimately, awareness and proactive measures are key to preserving the natural color of teeth. Whether through simple daily habits or professional teeth whitening treatments, managing tooth discoloration effectively contributes to overall dental health and enhances personal confidence in one’s smile.
- Jackson BA, Taylor CD. Sudden Onset of Tooth Discoloration. J Clin Aesthet Dermatol. 2019 Oct;12(10):12-13. Epub 2019 Oct 1. PMID: 32038742; PMCID: PMC6937148. ↩︎
- Wang, Jun, Dongna Zou, Yuchao Li, Pingping Liu, and Chenyu Guo. “Drug-induced tooth discoloration: An analysis of the US food and drug administration adverse event reporting system.” Frontiers in Pharmacology 14 (2023): 1161728. ↩︎
- Tiwari M. Science behind human saliva. J Nat Sci Biol Med. 2011 Jan;2(1):53-8. doi: 10.4103/0976-9668.82322. PMID: 22470235; PMCID: PMC3312700. ↩︎