The present invention is directed to a device and method for cleaning endodontic files and a device for indicating flaws such as stress fractures and deformations in endodontic files. The invention also includes a method for detecting flaws in endodontic files.
An endodontic file, also known as a reamer, is a tool used to perform endodontic procedures. In an endodontic procedure, such as a root canal, the tissue in the pulp canals of the tooth is broken up with an endodontic file. The file is also used to mechanically clean and shape resultant tissue debris which includes pulp tissue and dentin from the tooth. Additionally, the file removes the tissue debris from the tooth during the endodontic procedure. The endodontic file can be manually manipulated during use or it can be attached to and rotated by a motorized drill.
An endodontic file generally comprises a shaft with flutes along its length. Because of the file's design and function, the tissue debris that has been loosened from the tooth can accumulate on the file during use, such that the flutes become clogged with the tissue debris. The accumulation of such debris on a file can cause deformation of the flutes which can lead to stress fractures and breaks in the file. Consequently, it is desirable to remove the debris from the file and flutes at regular intervals during the course of an endodontic procedure. Regular cleaning of the file during use reduces the risk of file damage and allows for an unimpeded visual inspection of the file.
Typically, to clean a file during or after an endodontic procedure the file is wiped down to remove as much tissue debris as possible from the flutes. However, such a cleaning method is problematic since the flutes on the file make it difficult to wipe the debris from the file. Likewise, rinsing the file is ineffective in removing all of the debris that lodges in and around the flutes. Tissue remaining on the file can inhibit the user from visually detecting deformations in the file. Unchecked accumulation of debris on the flutes can cause deformations to form in the file which can create stress fractures and eventually cause file breakage. Failure to promptly detect such flaws can prompt continued use of the file and its eventual failure during use.
After an endodontic procedure, a file is typically cleaned to remove the tissue debris and then sterilized to prepare it for subsequent use with another patient or procedure. Debris that has not been completely removed from an endodontic file during such cleaning is not generally removed by standard sterilization procedures, such as autoclaving and ultrasonic cleaning. Consequently, tissue debris can remain on the file during and after sterilization. Using a file with tissue debris still adhering can compromise the requisite health standards for an endodontic procedure by increasing the risk of infection to the patient. Therefore, not only does using a file with debris clogged in its flutes further increase the possibility of file failure, but it can also present a health hazard.
Endodontic files are required to endure sustained pressure during use, despite their flexibility. Therefore, the files are designed and manufactured for strength and durability. However, when weakened due to repeated use, a file has the tendency to deform and develop stress fractures. Deformations and stress fractures in a file can lead to an endodontic file breaking apart. Since the files are used in a patient's tooth, a file breaking during use can be especially hazardous. When a file breaks apart in a tooth, the procedure must be halted while the broken file pieces are retrieved from the patient's mouth. This can be frustrating and time-consuming. As a result, file breakage not only creates a safety hazard and potential liability, it can unduly prolong the endodontic procedure. Stress fractures in endodontic files are generally undetectable to the naked eye. Methods of detecting stress fractures including X-ray techniques have been developed, but due to cost and time constraints, such techniques are impractical to use in routine clinical procedures. Stress fractures, along with deformations, can be especially difficult to detect when the file has an accumulation of tissue debris in and around the flutes.
As a precautionary measure to minimize file breakage, a user generally replaces the file after a recommended period of use. By regular replacement according to a manufacturer's recommended usage, file breakage can be minimized, but the life of the file is foreshortened resulting in increased cost to the user. Even if the file is discarded as recommended by the manufacturer, stress fractures, file deformation and breakage can still occur due to cyclic fatigue.
Regardless of a file's foreshortened life, such recommended time periods generally would not apply to files having manufacturing defects. Such defects can allow file deformations and stress fractures to form prematurely resulting in unexpected failure and file breakage, sometimes while the file is in use.
Therefore, there is a need for a device that can readily indicate flaws in an endodontic file while using the file in an endodontic procedure. There is also a need for a method for readily detecting flaws in endodontic files. The need also exists for a device and method to effectively clean tissue debris from an endodontic file, especially around the flutes, during and after an endodontic procedure in order to reduce the possibility of file damage, including breakage, and to lower the risk of patient infection resulting from an unclean file.