What causes failure in dental turbines?
•Bearings (specifically the bearing cage) will generally fail first, mostly because of: 1.Debris
2.Excessive air pressure
3.Excessive temperatures during sterilization
4.Side load stress
5.Water from air storage tank of compressor
6.Use of bent burs or a bur that is not fully seated
7.Using low cost ball bearings of unknown producers
•Rapid cool downs of handpieces after sterilization with cold water. Rapid cool downs could cause warping of handpiece components and you could also introduce contaminants onto your sterilized instruments.
•Running handpieces without burs. Doing so could cause damage to the spindle/chuck assemblies.
•Irregular lubrication. The chuck must be lubricated at least once a week to keep it clean and functioning well. Debris can clog the chuck and interfere with holding the bur.
•Very important is to use correct burs. One of most common failure in dental turbines is the using of incorrect burs with les then 1,59 mm diameter. Unfortunately there are many thinner and softer burs on the market coming from low costs productions and in turn available at attractive prices. If burs are too narrow or to soft, the chuck cannot hold them well. During the rotation of 300.000 revolutions per minute or more, incorrect burs will sooner or later start to deviate and consequently cause failure of chuck mechanism.
•Another fact that causes bur eccentricity is guiding bushing (a hole into which bur is inserted) non-resistance to wear. The guiding bushing must be made of carbide or hardened steel and it must be separated from chuck (see pictures below). Many after-market producers of dental handpiece rotors combine the chuck and guiding bushing into one part because it simplifies the spindle design and thus saves costs. But this technique is not optimal for the bushing?s wear resistance. Pressures that are put on the bur during operation can create wear in the guiding bushing, giving the bur more space to move radially. Because of this radial play dentists cannot work precisely with their handpiece anymore. Increased pla combine the chuck and guiding bushing into one part because it simplifies the spindle design and thus saves costs. But this technique is not optimal for the bushing?s wear resistance. Pressures that are put on the bur during operation can create wear in the guiding bushing, giving the bur more space to move radially. Because of this radial play dentists cannot work precisely with their handpiece anymore. Increased play will also reduce bearing lifetime. Call Precision Handpiece Repair LLC if you have any other questions at 513-293-3341 We service Ohio, Kentucky and Indiana -