Tooth polishing is one of the last steps your hygienist takes during a regular cleaning appointment. It removes superficial stains that aren’t embedded in the plaque or calculus deposits.
Dental professionals must choose a polishing paste and device carefully with the patient’s specific needs in mind. The goal is to minimize damage and abrasion.
The dental hygienist uses an abrasive agent to polish the tooth structures and restorative materials. This is done to remove extrinsic stains that are not removed during scaling and to make the teeth shiny and lustrous. These abrasive agents are embedded in a moist substance which is referred to as a polishing paste or slurry depending on the amount of liquid contained in the paste. The lubricating agent is used to minimize friction and wear on the abrasive surface of the abrasive and to diminish the heat generated by the abrasion of the abrasive on the tooth structure and restorative material(s).
A fine grit silica, such as chalk or pumice, is the most commonly used abrasive in prophylaxis toothpastes. A finer abrasive, such as aluminum oxide, is also used in polishing pastes and is impregnated into rubber wheels and points for polishing gold and amalgam restorations as well as acrylic denture bases and plastic materials.
Newer polishing devices allow the hygienist to use air, water, and an abrasive compound such as sodium bicarbonate or glycine to polish the tooth surfaces. These newer polishing systems are less abrasive than traditional rubber cup and prophylaxis point and generate minimal thermal heat. However, further research is needed to determine whether these products provide the same efficacy as traditional polishing. If future research supports these products, their definition may evolve to include the delivery of an active agent that controls a disease process; for example, fluoride or ACP to encourage tooth remineralization or to treat dentinal hypersensitivity.
Tooth polishing is often a very short procedure that usually takes place near the end of your hygiene appointment. It helps to remove any residual plaque that may have been left behind from the manual instrumentation where your hygienist was using those little picks (also called scalers) to clean off the heavier buildup.
Generally, your dental hygienist will use a rubber cup or prophy paste, which contains polishing and cleaning agents. It is typically a fine grit and contains fluoride. The pressure and speed of the rubber cup should be kept to a minimum to prevent tooth abrasion. It should contact the tooth for about 4.5 seconds at a rotation of 2500 rpm.
Some polishing systems use a wand that sprays out a fine mist of water mixed with a powder. It is a more efficient way to remove staining than traditional polishing with a brush and abrasive paste. Most prophy pastes are flavored, such as mint, berry or bubble gum.
Some patients experience temporary sensitivity following tooth polishing. This is because the abrasive particles can scrape the surface of the teeth and expose sensitive tissue. However, this sensitivity usually subsides within a few days. Depending on the condition of your teeth and your existing oral health, your dentist or dental hygienist will advise you whether tooth polishing is advisable for you.
While polishing is often considered a cosmetic procedure, it’s an important part of oral prophylaxis. When bacteria stick together on a tooth surface, they form a sticky substance called biofilm that can lead to gum disease (called periodontitis). Biofilm is removed regularly with brushing and flossing to keep it from building up and damaging teeth and the gums.
Tooth polishing removes soft biofilm that isn’t removed by scaling and scraping with a scaler, as well as some of the hardened plaque and tartar that has already calcified on teeth surfaces. Polishing with a rubber cup and prophy paste is typically one of the last steps in a cleaning appointment, after the hygienist scales away loose plaque and calcified tartar. The hygienist uses a low rotational speed and light pressure to ensure that the polishing materials don’t damage or harm the gum tissue or tooth enamel.
The amount of abrasive in the polishing product and the method used to apply it impacts the rate of abrasion. A dry polishing agent creates a faster rate of abrasion and generates heat, while a slurry of abrasive particles creates a slower rate of abrasion with less frictional heat.
The type of stains on the teeth can also impact the polishing process. Stains can be classified as endogenous or exogenous. Endogenous stains are stains inside the enamel of the tooth caused by developmental, drug-induced, or environmental factors. Exogenous stains are on the outer surface of the tooth and include staining from foods, beverages, smoking, some antimicrobial rinses and other external factors.
Polishing is one of the last steps in a preventive cleaning, usually performed after the hygienist scales away calcified plaque (also known as tartar). Once it hardens, it becomes very difficult to remove with brushing and flossing, making it a breeding ground for bacteria that lead to gum disease and tooth decay. Tooth polishing makes teeth feel smooth and shiny after a prophylaxis cleaning, but it has not been shown to make any difference in the prevention of gum disease or tooth decay.
In fact, it has been shown that polishing can cause abrasion and weakening of the enamel surface, which leaves the tooth slightly more vulnerable until the outer layer of enamel grows back. In addition, polishing can also abrade and remove fluoride from the outer surface of the tooth. For these reasons, many hygienists are opting to limit or eliminate polishing for their patients.
Depending on the abrasiveness of the polishing paste used and the technique, coronal polishing can abrade and alter the surface characterization of natural tooth structure as well as cosmetic restorations. For example, pumice-based prophy pastes may reduce the gloss on microfill and nanofill composites, ceramers, porcelain and titanium restorations.
In addition, polishing can produce aerosols that can contaminate hard surfaces and soft tissue. Hygienists must be aware of how these particles can leave the mouth during the procedure, and take precautions to protect themselves as well as the patient.