Thursday, March 16, 2017

Removing the Stain by Dental Air Polisher

Researchers and manufacturers caution against prolonged use of the air polisher on cementum and dentin. When moderate to heavy stain is present on root surfaces, dental hygienists are often faced with the problem of removing it with the least alteration of cementum.

One choice is to leave the stain and explain to the patient that stain is not associated with oral disease and will not harm the teeth or gingiva since it is only a cosmetic concern. To many patients, this is not a viable choice since appearance is considered so important in today's society.

Other choices include removing the stain with a rubber cup polisher and prophylaxis paste; sonic, ultrasonic scalers; Dental Hand Instruments or the air polisher. Wilkins recommends removing as much stain as possible during root planing with curets. However, in one in-vitro study, air polishing was shown to remove less root structure than a curet in simulated three-month recalls for three years. Woodall agrees that the air polisher may be preferable to curets in this situation. Since less root structure(endo equipment) is removed, decreased root-surface sensitivity also may be a benefit.

Air polishing units typically generate a stream of pressurized air, carrying specially graded particles of a mild soluble abrasive, such as sodium bicarbonate. The abrasive is directed, in the presence of a stream of water, at a tooth surface to be cleaned. The mixture of water and powderladed stream occurs on the tooth surface and forms a “slurry” that is responsible for the cleaning action.

Effects of air polishing on gold foil, gold castings, porcelain, amalgam, and glass ionomers have been studied. Air polishing of amalgam alloys and other metal restorations has produced a variety of effects, including matte finishes, surface roughness, morphological changes, and structural alterations.

Wednesday, March 1, 2017

How to Detect the Situation of Air Compressor

Studies have concluded that industrial plants waste roughly 30 percent of generated compressed air, which could equate to $9,600 for a typical scfm installation, or as much as $32,100 for 1,500 CFM. Estimates also indicate that poorly designed compressed air systems in the U.S. result in wasted utility payments of up to $3.2 billion.

Energy efficient dental air compressors will not only save money but will also help control pollution. A walk-through assessment can help identify conservation opportunities in your compressed air system.

Due to problems with piston rings on reciprocating compressors and premature modulation on rotary screw compressors, many compressors don’t produce the CFM flow for which they’ve been rated. Failure in this area may be the result of an inaccurately adjusted valve. Calibration can help verify compressor output.

Air compression equipment should maintain low pressure drop for the duration of its service life. Total pressure drops across system components shouldn’t exceed 15 psi. If pressure loss in your system is more than 10 percent, you should evaluate the distribution system and identify the causes of excessive pressure drops.

Air distribution piping should be large enough in size to minimize this pressure drop. Installing a pressure regulator can limit air demand while reducing maintenance costs and extending tool life. Inlet air filters can prevent the kind of dirt that restricts airflow and causes pressure drops.

The average system loses between 25 to 35 percent to leaks, so cost controls require routine monitoring and repairs. Air leaks can be the largest waste of compressed air energy at a manufacturing plant. For example, an eighth-of-an-inch diameter leak in a 100 psi system can cost more than $12,000 annually in unused energy.

If you don’t have a routine for regular leak inspections, you should put one in place. Maintenance personnel should have proper leak detection equipment. You can test your system with an ultrasonic leak detector during periods of nonproduction to determine overall leak rate by examining air loss from the supply tank. You may need a professional auditor to conduct a thorough leak audit.

Dust or sludge in a compressed air compression system can cause corrosion, which will increase the likelihood of leaks. Keep in mind that fixing a leak may increase system pressure, which means other unnoticeable leaks may grow. It takes routine maintenance to manage and control leaks.