Frequently Asked Questions
What causes my teeth to be sensitive to cold?
What causes recession?
What is a good "bite"?
What is abfraction?
How do you change the bite?
Are amalgam (silver) fillings safe and recommended?
What can I do if I have bad breath?
How often should I see my dentist?
Sometimes a client will have questions that they are embarrassed to ask. Sometimes they will have complex questions that require significant evaluation to answer. We have provided some frequently asked questions and answers in the section below, hopeful that you will find them informative.
What causes my teeth to be sensitive to cold?
The three main causes of cold sensitivity are cavities, recession/bone loss, and occlusal trauma (excessive unhealthy biting forces). A comprehensive dental examination will reveal the cause. Use of desensitizing agents (eg. Sensodyne) may be effective but mask rather than cure the problem. Teeth with cavities require restorations. For treatment of the other problems read along.
What causes recession?
Recession was once thought to be caused by aggressive tooth brushing but that is no longer a widely held view. The cause of recession is almost always "a bad bite". If your "bite" or occlusion causes excessive forces particularly sideways or lateral stresses on teeth, the teeth will lose bone on the side of the tooth and will lose gum height (recession). The recession is a concern but the underlying bone loss is an even greater worry. It is certainly true that "old" people with a good bite and good oral hygiene will not have recession/bone loss.
What is a good "bite"?
Evaluation of your bite must really be done by a dentist trained in occlusion. However a few concepts apply that you may be able to check.
Firstly, when you slide your jaw to one side with your teeth contacting, only teeth on that side should contact. Contacts on the opposite side (called Balancing Contacts) will cause patients to grind their teeth and often this grinding will occur during sleep (called Bruxing). This causes harmful stresses on the teeth that result in bone loss on the side of the teeth as well as recession.,
Secondly, when you slide your jaw to one side with your teeth contacting, the teeth on that side should gradually only contact on anterior teeth. The brain has protective mechanisms to protect your teeth (if you have a good bite) and will prevent excessive/harmful forces on teeth.
Take this test, hold your hand over your massater muscle, the big muscle of your face, over the back corner of you jaw Clench on your back teeth and feel the power developed in this muscle. Now slide your jaw forward so that only front teeth are touching. Bite as hard as you can on your front teeth and notice that this muscle develops only a fraction of the activity it did earlier. This occurs because of the body's protective mechanisms. If your bite is good, when you slide a short distance to one side your body will protect your teeth by limiting the muscle forces. If your bite is unhealthy you will develop excessive forces that result in bone loss, recession and abfraction.
What is abfraction?
Abfraction is the development of a groove in the outside root surface of a tooth. This develops because of the same harmful biting forces described above. What actually occurs is a flexing or bending of the tooth because of these harmful sideways forces, and tooth structure on the root shears off. These areas are sometimes filled by your dentist but occasionally these fillings fall out because of continued bending of the tooth unless the bite is changed.
How do you change the bite?
The bite can be changed temporarily with a plastic removable appliance (orthotic) which is for short or long term use or it can be changed permanently with orthodontics, an occlusal adjustment (selective enamel contouring) or with crowns and veneers. More importantly is how we determine where the bite should be. You will see on the Neuromuscular P age that Dr. Bonazza is trained in advanced techniques for determining the bite position that offers the most relaxed muscle condition in harmony with the teeth and joint. The K7 Evaluation System provides computerized muscle activity recording while simultaneously tracking jaw position (among other things). Changing the bite with crowns and veneers also has the added benefit of producing spectacular cosmetic results ie.wighter, straighter and aligned teeth- a smile makeover.
Are amalgam (silver) fillings safe and recommended?
My answers to these two questions is very different. Silver amalgam contains mercury in a form that is bound to other metals. It is in a different form than the shiny silver liquid that some of us have seen in science class. However, it is the mercury that is a health concern to some. Many thorough and well controlled, double blind studies have been done and have demonstrated no adverse health effects in populations of people with silver fillings as compared with populations without silver fillings. Still, there are testimonials by some who believe their health problems were caused by amalgam. Some European states have directed dentists not to use the product. Also, Canadian dentists are now required by law to have amalgam recovery systems to prevent amalgam from entering the sewer lines. (We have such a system). Though Dr. Bonazza does not have a serious health concern with the use of amalgam, he very rarely uses it. My greatest concern with the use of amalgam is that it has been shown to expand in time as it corrodes and many dentists (including me) believe that it causes craze lines, microfractures, cracks and eventually fractured or cracked teeth. White (composite) filling is much better at bonding to surrounding tooth structure and hence, preventing fractures. Teeth that require larger restorations should receive crowns or laboratory processed large fillings (sometimes called inlays or onlays). Furthermore, the cosmetic benefits with nonmetal restorative options are undisputable.
What can I do if I have bad breath?
Bad breath or halitosis is most frequently caused by bacterial accumulation on the teeth in the form of plaque (soft) or calculus/tarter (hard). Thorough removal of the buildup by a trained hygienist and good home care in the form of brushing, flossing and use of a waterpik to prevent more accumulation, will solve this problem. Regular dental visits are required to maintain clean teeth and healthy gums. Bacteria can also accumulate on the tongue and use of a tongue scraper may help some patients. Rowpar produces a good kit for just this purpose though it is not distributed in Nova Scotia. Patients with periodontal disease will harbour more bacteria and they will be more difficult to remove. Treatment of the condition is required to resolve the halitosis. Another cause of bad breath is stomach acids and their odor. Often if bad breath develops during long periods between meals this is the reason and we would recommend drinking water more regularly. More frequent snacking will also eliminate the problem but can contribute to cavities and gum disease if one can't brush afterwards. More frequent brushing will also help. Some foods will cause bad breath and in particular the avoidance of garlic and onions will be effective. Tobacco either smoked or chewed will cause halitosis. Cessation of these habits will have far greater benefits than elimination of bad breath alone.
How often should I see my dentist?
The answer to this question varies with each patient. In most cases patients should have hygiene maintenance (cleaning above and/or below the gum as required) every six months. However, for those who have periodontal conditions or rapid, heavy buildup it should be more frequent, maybe every three months. Conversely, those who have meticulous oral hygiene habits may only need hygiene maintenance every 9 or 12 months. Once we know your dental condition and your oral hygiene habits, a personalized recommendation will be provided. A dental examination to detect cavities and gum disease is most often done every six months, but again, some only need an examination annually.
For an appointment call:
(902) 442-0200
Speak with Robyn
DR. BONAZZA IS RELOCATING ACROSS PORTLAND ST. AT EVERGREEN PLACE IN JANUARY 2009. See the Office News page
Our Location
Dr. Bonazza currently practices at
Penhorn Dental Center
Penhorn Mall
535 Portland St.
Dartmouth, NS
B2Y 4B1
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