MAUDE Adverse Event Report: NAKANISHI INC. (NSK) NSK X-SL

Model Number X-SL

Device Problem Detachment Of Device Component (1104)

Patient Problem Injury (2348)

Event Date 07/08/2014

Event Type  Injury  

Event Description

This mdr is being reported at this time as part of our internal review of past complaints and service records.Due to the incident being in the past, we are limited in the info that we can obtain from the initial complainant.Event summary: according to the dentist, a bur detached from a handpiece during treatment and the bur hurt inside of the patient's mouth.Complaint review: cartridge was replaced on (b)(6)2013.

Manufacturer Narrative

Investigation: nakanishi received the handpiece on (b)(6) 2014 and conducted an analysis and investigation.Upon receipt from the dentist of the device involved in the mdr event, nakanishi conducted a failure analysis of the returned device that included an attempt to measure the retention force of the operating device.These activities are described in more detail below: methodology used: nakanishi examined the device history records for the subject x-sl (serial number (b)(4)).There were no problems observed during the manufacturing or testing noted in the dhr.Nakanishi conducted a visual inspection of the returned device and performed a simple movement test.There were no visible abnormalities, such as cracks or debris, on the outside of the handpiece.Nakanishi measured bur detachment force by setting a test bur in the handpiece and confirmed it was 20.0n.Nakanishi's acceptance criteria for the bur detachment force is 14.7n or above, indicating that the bur detachment force of the subject handpiece had not deteriorated.Rotation was smooth without any damage.Nakanishi disassembled the handpiece to observe the inside of the chuck, compared to an unused new chuck and took photographs.Nakanishi observed the retention surface of the chuck had worn.Conclusion reached: the bur detached from the handpiece due to the deterioration of the bur retention torque that was caused by the worn chuck.Nakanishi believes that there are two causes for the wear of the chuck: the handpiece had been used with the dirt and debris inside the chuck: the handpiece was used under the load and rotational speed that were higher than those specified with the retention capacity of the chuck.Nakanishi reminded the user of the instruction included in the user manual in order to prevent the dirt or debris accumulated inside the chuck.This event occurred in japan, but the similar products are marketed in the us under k113655.

• Brand Name: NSK X-SL
• Manufacturer (Section D): NAKANISHI INC. (NSK); 700 shimohinata; kanuma-shi, tochigi-ken 322- 8666; JA 322-8666
• Manufacturer (Section G): NAKANISHI INC. (NSK); 700 shimohinata; kanuma-shi, tochigi-ken 322- 8666; JA 322-8666
• Manufacturer Contact: ken block ; 1201 richardson dr.; ste 280; richardson, TX 75080 ; 9724809554
• MDR Report Key: 4805641
• MDR Text Key: 5918535
• Report Number: 9611253-2015-00068
• Device Sequence Number: 1
• Product Code: EFB
• Combination Product (y/n): N
• Reporter Country Code: JA
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Distributor
• Reporter Occupation: Service Personnel
• Type of Report: Initial
• Report Date: 05/21/2015

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Other
• Device Model Number: X-SL
• Device Catalogue Number: P496003
• Was Device Available for Evaluation?: Yes
• Date Returned to Manufacturer: 08/01/2014
• Is the Reporter a Health Professional?: No
• Initial Date Manufacturer Received: 08/01/2014
• Initial Date FDA Received: 05/26/2015
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 10/01/2009
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Reuse
• Patient Sequence Number: 1
• Patient Outcome(s): Other