MAUDE data represents reports of adverse events involving medical devices. This maude entry was filed from a distributor,health profession report with the FDA on 2016-08-23 for NSK SGA-E2S H265001 manufactured by Nakanishi Inc..
[52736346]
(b)(4). (b)(4) contacted the dentist and details are as follows: on july 29, 2016, (b)(4) contacted the dental office to inquire if assistance was needed with sending the handpiece to (b)(4). There was no response from the dental office. As of this date, (b)(4) has not received the handpiece from the dental office.
Patient Sequence No: 0, Text Type: N, H10
[52736347]
On august 2, 2016, nakanishi received an email from a distributor ((b)(4)) describing a burnt to a patient. Details are as follows: on july 19, 2016, (b)(4) was made aware of an unconfirmed patient burn from a dentist. The dentist explained that the dentist burned a patient while removing wisdom teeth. The dentist was working on the left side. The dentist noticed a white spot on the inside cheek after the removal. The dentist claimed the handpiece was not hot to the touch. The dentist proceeded to remove the right side wisdom tooth and noticed a white spot on the patient's lip. (b)(4) contacted the dentist to obtain more information needed, and the (b)(4) patient information form was forwarded to the dentist to complete, along with a shipping label for sending the handpiece in question to (b)(4). (b)(4) received the patient information form from the dentist on july 26, 2016 and details are as follows. The dentist stated that iv sedation with local anesthesia was administered. No malfunction was observed by the dentist prior to the procedure. At the end of the procedure, there was evidence of lip and skin injury. The patient sustained lip trauma on right side and skin trauma on left side. The patient sought a dermatologist, and the patient was classified by the dermatologist as having a second-degree thermal burn. The patient was seen by dermatologist 2 days post-injury, and rx cream was prescribed along with a topical antibiotic ointment.
Patient Sequence No: 0, Text Type: D, B5
[64628285]
Upon receiving the device involved in the adverse event, nakanishi conducted a failure analysis of the returned device: methodology used: nakanishi examined the device history record for the subject sgs-e2s device (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: nakanishi set a test bur in the handpiece and rotated it by hand. Nakanishi observed a rotational resistance; nakanishi did not observe any damage on the exterior. Investigation of overheating: temperature sensors were first attached to the exterior of the device at various test points (i. E. Most proximal to the patient, testing point (1), and along points further toward the distal end of the device, testing points (2) through (4)). The test was set up to take temperature measurements at all points simultaneously, including a reference measurement at ambient room temperature; nakanishi attached a thermocouple (sensor to measure temperature) to each point. Nakanishi rotated the motor at 40,000 min-1, which is the maximum rpm for the motor that drives the handpiece (80,000 min-1 for the handpiece), and measured the exothermic situation; nakanishi observed an abnormal rise in temperature at test point (2) 16 seconds after the start. Temperature measurements 16 seconds after the start are as follows: test point (1): 44. 6 degrees c; test point (2): 105. 2 degrees c; test point (3): 30. 6 degrees c; test point (4): 30. 9 degrees c. The temperature testing was conducted for 16 seconds into the planned 5 minute evaluation; nakanishi washed the inside of the handpiece using nakanishi pana spray plus, as defined in the operation manual. Nakanishi observed dirt/debris being expelled from the head of the handpiece by using a white filter to catch anything that was expelled; nakanishi measured the temperature rise of the handpiece cleaned using pana spray plus the way described. Nakanishi still confirmed an abnormal temperature: 93. 2 degrees at test point (2). Identification of the specific failure mode(s) and/or mechanism(s) and the associated device component(s) involved: nakanishi disassembled the handpiece and performed a visual inspection of the inside parts. Nakanishi observed that the bearings were dirty. Nakanishi also observed corrosion on a part of the spindle; nakanishi took photographs of all of the disassembled parts and kept them in a file; nakanishi then replaced the bearings and measured the exothermic situation yet again. There was no abnormal rise in temperature during the test period. Nakanishi confirmed that the returned handpiece was operating as expected and within temperature specifications once the damaged bearings had been replaced. Conclusion reached based on the investigation and analysis result: nakanishi identified that the cause of the overheating of the returned device was abnormal resistance during rotation caused by dirt in the bearings; a lack of maintenance causes the accumulation of dirt (abrasive powders/foreign materials) in the inside parts, which causes dirt/debris ingress into the bearing during rotation. This contributes to the handpiece overheating; in order to prevent a recurrence of the handpiece overheating, nakanishi took the following actions: nakanishi reviewed the operation manual and reconfirmed clarity and understandability of the instructions; nakanishi reported the above evaluation results to nsk (b)(4) and directed nsk (b)(4) to remind the user of the importance of maintenance, as instructed in the operation manual.
Patient Sequence No: 1, Text Type: N, H10
| Report Number | 9611253-2016-00045 |
| MDR Report Key | 5895990 |
| Report Source | DISTRIBUTOR,HEALTH PROFESSION |
| Date Received | 2016-08-23 |
| Date of Report | 2018-07-10 |
| Date of Event | 2016-07-18 |
| Date Facility Aware | 2016-07-19 |
| Report Date | 2016-08-01 |
| Date Reported to Mfgr | 2016-08-01 |
| Date Mfgr Received | 2018-06-09 |
| Device Manufacturer Date | 2011-06-03 |
| Date Added to Maude | 2016-08-23 |
| Event Key | 0 |
| Report Source Code | Manufacturer report |
| Manufacturer Link | Y |
| Number of Patients in Event | 0 |
| Adverse Event Flag | 3 |
| Product Problem Flag | 3 |
| Reprocessed and Reused Flag | 3 |
| Reporter Occupation | DENTIST |
| Health Professional | 3 |
| Initial Report to FDA | 3 |
| Report to FDA | 3 |
| Event Location | 3 |
| Manufacturer Contact | MR KENNETH BLOCK |
| Manufacturer Street | 800 E CAMPBELL RD. SUITE 202 |
| Manufacturer City | RICHARDSON TX 75081 |
| Manufacturer Country | US |
| Manufacturer Postal | 75081 |
| Manufacturer Phone | 9724809554 |
| Manufacturer G1 | NAKANISHI INC. REGISTRATION NUMBER 9611253 |
| Manufacturer Street | MFR RP#:9611253-2016-00045 700 SHIMOHINTA |
| Manufacturer City | KANUMA-SHI, TOCHIGI-KEN 322-8666 |
| Manufacturer Country | JA |
| Manufacturer Postal Code | 322-8666 |
| Single Use | 3 |
| Previous Use Code | 3 |
| Removal Correction Number | 9611253-060818-001-R |
| Event Type | 3 |
| Type of Report | 3 |
| Brand Name | NSK |
| Generic Name | HANDPIECE, ROTARY BONE CUTTING |
| Product Code | KMW |
| Date Received | 2016-08-23 |
| Model Number | SGA-E2S |
| Catalog Number | H265001 |
| Operator | DENTIST |
| Device Availability | N |
| Device Age | 5 YR |
| Device Eval'ed by Mfgr | Y |
| Device Sequence No | 1 |
| Device Event Key | 0 |
| Manufacturer | NAKANISHI INC. |
| Manufacturer Address | 700 SHIMOHINATA KANUMA-SHI, TOCHIGI-KEN 322-8666 JA 322-8666 |
| Patient Number | Treatment | Outcome | Date |
|---|---|---|---|
| 0 | 0 | 1. Other | 2016-08-23 |
| 1 | 0 | 1. Other | 2016-08-23 |