Sensitive Teeth

Teeth can become sensitive for many reasons. Sometimes, the sensitivity is an indication of a potentially serious problem. Other times, the dentally related problem may be small but the effects (the sensitivity) are extremely aggravating. 

What do we mean when we say "sensitive teeth?"
Twinges of pain or discomfort in our teeth in certain situations such as drinking or eating cold things, drinking or eating hot things, eating sweets, and touching the teeth with other teeth or the tongue. Your symptoms will involve reactions to temperature or pressure. Sensitivity to cold drinks or foods is the most common symptom. 

Two types of sensitivity:

1. Dentinal sensitivity
When the dentin (middle layer) of a tooth is exposed. Normally, dentin is covered by enamel. Dentin becomes exposed when the outer protective layers of enamel wear away. Dentin contains tiny openings called tubules. Inside each tubule lies a nerve branch that comes from the tooth's pulp (the nerve center of the tooth). When the dentin is exposed, cold or hot temperature or pressure can affect these nerve branches, causing sensitivity.

Causes:

• Inadvertent notching of the tooth surface and/or recession of the gum tissue (exposing the root surface of the tooth) caused by improper brushing: either brushing too hard, brushing with a toothbrush that is too hard, or using an improper brushing technique, which will wear away the enamel layer. This sensitivity can range from mild to extreme; the degree of sensitivity does not appear to be related to the size of the root exposure or notch.
• Poor oral hygiene, allowing tartar to build up at the gum line
• Untreated cavities
• An old filling with a crack or leak
• Receding gums that expose the tooth's roots, often caused by periodontal disease
• Gum surgery that exposes the tooth's roots
• Tooth whitening in people who have tooth roots that already are exposed
• Frequently eating acidic foods or drinking acidic liquids 
• Purposeful repositioning of the gum tissue during gum surgery can also lead to tooth sensitivity. While recession from brushing is slow, gum recession following gum repositioning occurs very quickly. The portion of the tooth once covered with gum and bone may now be exposed.  Root sensitivity in these instances can be quite severe and immediate. It can sometimes last four months or years if not treated.

2. Pulpal sensitivity
The reaction of the tooth's pulp. The pulp is a mass of blood vessels and nerves in the center of each tooth. Pulpal sensitivity affects only a single tooth.
Causes:

• Decay or infection. When a tooth is decayed, temperature changes and sweets will make it sensitive. The solution can be as simple as removing the decay and placing an appropriate restoration.
• A recent filling. A tooth may be sensitive to cold for several weeks after you get a filling. The metals in amalgam (silver) conduct the cold very well, transmitting it to the pulp. Bonded (tooth-colored) fillings require etching the tooth with acid before the filling is placed. In some cases, this etching removes enough enamel to make the tooth sensitive. If a filling is defective or failing, leakage around the filling may cause the tooth to become sensitive. The solution can be as simple as removing the defective filling and placing an appropriate restoration.
• Excessive pressure from clenching or grinding
• A cracked or broken tooth. If the tooth is fractured, you may be sensitive to temperature changes or when chewing food. This fracture condition may be hard to diagnose. If you think you might have this type of sensitivity, read our blog post on "cracked tooth syndrome."
• A tooth can become sensitive after it has been prepared (drilled) for a restoration (filling). You may have been anesthetized during the procedure, so you did not feel any discomfort when the nerve in the tooth reacted to the heat generated by the drill. The closer the drill comes to the nerve, the more likely it is to cause a sensitivity problem. The high-speed rotation of the bur in the drill generates heat, and the response of the nerve to heat is inflammation. This inflammation is felt by you as a "sensitivity."  If the decay, fracture, or drilling was not too deep, this sensitivity will decrease over time. A week to a month or two is not an unusual length of time for the sensitivity to disappear. A good sign is the continued decrease of sensitivity.  However, if the occlusion (bite) is off after the restoration has been placed, the tooth may either become sensitive or may stay sensitive. Once the bite is adjusted, though, the sensitivity should disappear.
• A dying nerve. This can be the result of a deep cavity. Commonly, the sensitive tooth holds an old large filling. The nerve may be damaged during drilling and the nerve has been dying gradually ever since. If this is the problem, the tooth will need endodontic treatment (root canal treatment).

See this post about the 10 biggest causes of tooth sensitivity.

How will the doctor diagnose sensitivity?
Your dentist will look at your dental history and will examine your mouth. You also will need x-rays to show if there is decay or a problem with the nerve. The dentist will ask about your oral habits. Grinding or clenching your teeth can contribute to sensitivity. Your dentist also will look for decay, deep fillings, and exposed root surfaces. During the consultation, your dentist uses an instrument called a spray gun to dispense air across every area of each tooth in order to locate the sensitivity. He or she may use an explorer - a metal instrument with a sharp point - to test teeth for sensitivity.
 
How will it be treated?

• Your dentist or dental hygienist will clean your teeth. If your teeth are too sensitive to be cleaned, your dentist may use a local anesthetic or nitrous oxide before the cleaning. 
• If there is a notch in the tooth or the shape of the defect is appropriate, the defect is restored (filled in) with a bonded material. This can give immediate relief -- sometimes partially, sometimes fully. 
• When there is no defect to be restored, the exposed and sensitive root surfaces are covered with a dentin-bonding or other material. This material is invisible and has very little thickness, so you do not notice any change in the appearance of the tooth; but it works. It may have to be reapplied after several months because the bonding material has worn away by tooth-brushing.
• If you have pulpal sensitivity and the tooth's nerve is damaged or dying, you will need a root canal. Your dentist will remove the nerve and place a non-reactive substance in the space where the nerve was. The tooth will no longer have a continuous barrier of enamel to protect it. Therefore, it will be restored with either a composite filling or a crown.
• Your dentist may apply a fluoride varnish to protect your teeth. This temporarily reduces sensitivity and strengthens your teeth.
• Using fluoride toothpastes and fluoride mouth rinses are home will help to reduce sensitivity. You can also buy toothpastes just for sensitive teeth. You should choose a fluoride mouth rinse that uses neutral sodium fluoride.

How can I prevent it?

• Brush twice a day and floss daily
•  Use a soft or ultrasoft toothbrush 
• Brush gently up and down, rather than side to side 
• Use a fluoride toothpaste and mouth rinse 
• Use a toothpaste that protects against sensitivity 
• Get treatment for grinding or clenching your teeth (bruxism), like a mouthguard

If you have any questions about tooth sensitivity, please feel free to call our office for a consultation at (512) 250 - 5012.

Dental Injection

The amount of discomfort caused by any one dental injection can vary significantly. And even though so many patients are focused on the fact that a needle is involved, most of the pain from a dental injection is not related to the needle itself. Instead, it has to do with the location and type of tissue in which the shot is given.

Why is it not the needle's fault?
The needle initially does prick as it first enters the skin, but this only lasts for a split second. Once the needle is in position, the dentist does not move it around, so what would cause a further pricking sensation?

What is causing the pain?
The bulk of the discomfort that a patient experiences during an injection has to do with the act of placing a quantity of liquid (the anesthetic) into soft tissues. Shots in different locations have varying potential to hurt. It is the act of dispensing the anesthetic liquid into tissue that is painful.



Shots that are less likely to hurt:
Loose tissue: In some locations, the tissue receiving the injection is comparatively "loose," thus making it easy for the injected anesthetic solution to find a space to occupy.

• In locations where the tissue is relatively loose and flabby, the anesthetic solution will flow into the tissue easily and you probably will not feel the injection process much at all. Shots given on the cheek side of a person's upper molars, and probably even this bicuspids, involve this type of tissue and are often remarkably painless.

Shots that are more likely to hurt:
Dense tissue: In other areas, the construction of the tissue will be dense and tight. The anesthetic solution is injected, and it must forcibly make its own space - this is what pinches so much.

• In situations where the soft tissue receiving the injection is relatively tight and dense, the anesthetic liquid must force its way in. This type of instance is where you are likely to feel discomfort. As an example, injections given directly into the type of tight gum tissue that surrounds a person's teeth and covers over their palate are likely to pinch.

Will my shots hurt?
Ask your dentists what to expect with any specific injection. You may be pleasantly surprised to learn what they have to say.

What can I do to ease the pain?
Give your dentist some cooperation with the injection process. The more you cooperate with your dentist, the more pleasant the experience will be.

• The more you rush your dentist, the more likely it is to hurt: One factor associated with ease with which the anesthetic solution can enter into soft tissue has to do with the rate at which it is injected. The slower the rate, the less potential there is for discomfort.
• Be a cooperative patient: If you are an uncooperative patient, your dentist's natural instinct will be to speed up the injection process so it is finished more quickly. That is the exact opposite of what you want.
• Help your dentist be on-target, the first time: When a dentist performs a dental injection, they must place the anesthetic in the proper location. This takes a little concentration. If the dentist is focused on your behavior, as opposed to just performing the injection, it will increase the likelihood that the injection will be off-target and additional shots will be required. 
• If you want it to hurt, it will: Some people place themselves in a position of creating a self-fulfilling prophecy. They expect the injection to hurt and therefore do not give the process a chance, thus making a guaranteed unpleasant experience. 

If you have apprehensions about injections, let your dentist know in advance. They can address your concerns and take steps to make the process as pleasant for you as possible.