Many patients visit their dentists with complaints of tooth sensitivity to hot or cold foods and drinks. In fact, it is a very common problem, and is one of the major things that require a visit to the dental office. However, it is interesting to know that this painful condition can be easily avoided, if oral hygiene is meticulously maintained, and routine visits to the dentist are made in timely manner.
Causes of Tooth Sensitivity
Healthy human teeth are covered on the outside with a hard, protective layer known as the dental enamel. The enamel not only protects the teeth against fracture, but makes the tooth less sensitive to very hot or cold food stimuli. Beneath the enamel is the dentine layer, which is soft and highly sensitive to temperature changes within the oral cavity, due to the presence of sensory nerve endings within it.
In some cases, when the dental enamel is lost, either as a result of caries or due to tooth wear, the dentine becomes exposed. There are numerous tiny dentinal tubules, within the dentine, that can detect very minute temperature changes, which is manifested in the form of pain. Other causes of tooth sensitivity include frequent teeth bleaching, ultrasonic teeth cleaning, and teeth grinding.
Signs and Symptoms
Patients with sensitive experience a sharp pain upon ingesting hot or cold foods. The duration and intensity of the pain is mainly dependent upon the severity and extent of dentinal exposure. For acute cases, the pain is sharp, but does not last long and disappears as soon as the stimulus is ingested. In case of long standing tooth exposure or wear, the pain tends to persist for a longer duration, until a point is reached when the pain becomes permanent.
Detection of Tooth Exposure
Detection of the exposed tooth surface region must be made in order to treat dental sensitivity. Dentists use caries detecting solutions which stain the exposed tooth area. Similar, dental radiographs are taken, and darkening of the tooth regions indicates the presence of caries or any other dental infection.
Sometimes, the pain from sensitive teeth is referred to other teeth, making the identification of the effected tooth difficult. In these cases, a hot or cold stimulus test can be performed to isolate the sensitive tooth.
Treatment of Tooth Sensitivity
Before initiating treatment, it is imperative for the dentist to differentiate between reversible or irreversible causes of tooth sensitivity. In case of a reversible condition, only the dentinal tubules are exposed and the pulp is yet not involved, however, once the exposure advances into the pulp, it may get infected, leading to an irreversible condition.
In cases of reversible causes of tooth sensitivity, the treatment is aimed at occluding the exposed dentinal tubules, and includes the following:
- Application of Fluoride Containing Agents – the application of fluoride to sensitive teeth has been shown to occlude the dentinal tubules and reduce tooth sensitivity, while making the teeth stronger and more resistant to caries. Common forms of fluoride application include fluoride containing toothpastes, mouthwashes, and chewing gums which can be used at home, or special gels which are applied by a dentist. Similarly, some restorative materials also gradually leach out fluoride into the oral cavity, such as glass ionomer cements.
- Tooth Restoration- the exposed dentinal tubules are occluded with a suitable filling material, such as composites or glass ionomers. The filling materials not only treat the tooth sensitivity, but also replace the tooth structure lost as a result of caries.
An irreversible condition occurs whenever the dental pulp gets infected after an exposure. The treatment in this case involves the removal of infected pulp, followed by insertion of an inert material within the prepared root canal. This technique is commonly referred to as the root canal treatment.
A Final Word
Whatever the cause of tooth sensitivity, it is undoubtedly a painful condition and must be corrected at earlier stages through preventive measures. Long-standing cases need endodontic intervention, and tend to have relatively poor prognosis.