Abstract: The scaler includes a housing which is an angle piece and includes a grip housing and an instrument housing positioned at an angle to the grip housing. A scraper is inserted in a bearing sleeve mounted in bearings in the instrument housing and can be moved into different angular positions relative to the circumference of the bearing sleeve and can be fixed by rotating a coupling ring. A drive shaft is mounted in the grip housing. The drive shaft at its end face is provided with an eccentrically positioned driving pin and a coaxial bearing pin. An eccentric member is pivotable within an angular range on the bearing pin. This range is determined by the size of a recess formed in the eccentric member. A spring-loaded rocker cooperates with the eccentric member to perform a rapid jerky movement of the scraper relative to the instrument housing when the eccentric surface formed in the eccentric member faces the rocker.

Abstract: A dental instrument employs a tool having an upper portion for use in contacting teeth and a lower portion defining a shank with a lower end, a hollow elongated gripping holder having an opening at one end, a device in the holder communicating with the opening in the holder to removably receive said part of the shank, including the lower end; and a manually operated coupling mechanism having a first section connected to the holder and a second section on the shaft, the mechanism having a lock position at which the first section engages the second section in such a manner that the tool is locked in the holder in position for use, and having a release position at which the first and second sections are disengaging and the tool can be removed from the holder.

Abstract: A process for treating periodontitis existing in the mouth of a patient having teeth with roots extending downwardly in the gums by using a scaler including a scraper with a cutting edge and a handle for the scraper. A dentist uses the scraper to remove tartar, concretions and necrotic root element from a tooth by guiding the cutting edge along the tooth root under the gums from the lowest point of the gum pocket and while exerting pressure on the root suddenly moving the cutting edge with a powerful jerk in scraping manner toward the chewing face of the tooth. The scaler is adapted for manual movement by the dentist and also has a mechanism which when actuated initiates and performs the jerk action without manual movement of the scraper by the dentist.