Why use Air Abrasion for Cavity Preparation?
by Dr. Thomas E. Hughes, DDS, Colorado , USA
and Dr. Ray Bertolotti, DDS, California, USA
For many patients, the thought of going to the dentist evokes the whining sound of the dreaded drill and the sudden twinges of pain when the dentist explores around a cavity. It is no wonder that an estimated 75 percent of adults fear the dentist. Children are not born afraid of the dentist but often have unpleasant experiences or are inadvertently taught by others to be afraid. Dental air abrasion changes all of this. Dental air abrasion is a good alternative for all patients, especially young children and nervous/elderly patients who have more fear than tooth decay.
After practicing dentistry for more than 30 years, identifying truly useful dental technologies for the general practice of dentistry has become much easier. Air Abrasion and Adhesion Dentistry are two such technologies with many advantages for dentists and their patients.
Air abrasion is actually an older technology, and attempts to use it for dentistry pre-date high-speed rotary instruments by more than a decade. Dental air abrasion is essentially a miniature Intra-oral sandblaster ( like the PrepStart from Danville ) that produces a closely collimated stream of air and abrasive particles that efficiently removes tooth structure and tooth decay in a gentle but very efficient manner, doing the same job as the conventional drill without the side effects of vibration, noise, heat or pressure.
There is a closely related technology which is often called “microetching”, for example Danville’s Microetcher, is used for surface cleaning and roughening.
The Nozzle of Prep Start Air Abrasion Unit is much smaller than the sandblaster.
In addition to the surface cleaning and roughening applications, the Prepstart can also be utilized to prepare minimal/non-invasive Class I, III, IV, V, VI cavity preparations as well as tunnel preparations.
Unfortunately, predictable restorative dentistry accomplished with the aid of air abrasion had to await the development of good dental adhesives and small-particle flowable composites to make it efficient and cost effective. The evolution and combination of these two technologies, however, now make it possible for air abrasion to be a very productive and profitable treatment modality for any modern dental practice.
Air abrasion has many advantages for both the dentist and the patient. It is silent, fast, and cost effective. It produces no “burning” odors, no handpiece whine, no vibration, no pressure and no heat. Multiple quadrants can be treated in a single visit and most often it can be use without any local anesthetics. For these reasons, it is considered the most efficient method to remove tooth decay and prepare a tooth surface for adhesive dental materials.
Dental air abrasion can be used in virtually all the same processes that the traditional drill is used in. It is most commonly used to:
- Prepare one Class I cavity for a filling
- Remove old composite restorations
- Prepare a tooth for bonding or sealants
- Remove superficial tooth stains and discolorations.
- Reduces the need for anesthetics and, in many cases, eliminates it altogether
- Doesn't produce the burning smell associated with drilling
- Generates no handpiece whine, heat, pressure or vibration, which are the common complaints about the conventional drill
- Leaves more of the tooth intact
- Leaves the treated area of the tooth relatively dry, making sealants and filings bond better
- Reduces the risk of micro-fracturing, a problem sometimes caused by drilling.
- Reduces failure rate of bonded orthodontic brackets
- Increases retention of composite placed on unprepared enamel
The whole procedure is simple and quick, allowing the dentist to treat multiple sites in one visit, often without anesthesia. The hourly returns are far higher than with conventional dentistry where anesthetic is required. In addition, Air abrasion dentists enjoy more patient referrals for this technology.
Dental air abrasion has its disadvantages as well. First, the dentist must take care when using around gums and intra oral soft tissues as aluminum oxide particles from the instrument can hit gums, causing discomfort if the dentist does not avoid or protect them. Furthermore, air abrasion techniques can't be used for deep cavities that reach close into the tooth’s pulp. When used to prepare a tooth for a filling, only composite materials can be used since amalgam (unless bonded) requires retentive form that is not easily produced by air abrasion.
Summary
Air abrasion, in conjunction with microdentistry, has opened up a whole new method of treatment for patients that preserves far more tooth structure than was ever previously possible, with greater patient comfort and superior aesthetics. The resulting preparations and surfaces are also far better prepared to receive and retain bonded restorations compared with traditional methods of preparation. Air abrasion eliminates the needless destruction of sound tooth structure associated with traditional restorative techniques, while leaving the tooth ideally conditioned for the beneficial caries-inhibiting and strengthening properties of bonded restorations. What you dread most isn't the pain. Local anesthesia takes care of that. What patients dread is "the drill." which is eliminated.
The benefits to the patient are less dental fear and better dentistry. The economic benefits to the dentist are better returns and increased new patients by referral.