Investigation: fm176r: both gripis of the forceps are broken.Cracks can be found on the outside.On the inside, two of the four limitation stops are broken off, the fragments have not been provided.Fm178r: one grip of the forceps is broken.A crack can be found on the "sensation" labelled side.The breakage of the grips is traceable to a tensile stress above the tensile strength of the material, caused by shrinking, to be recognized by the lifted grip and the shear breakage pattern of the missing limitation stops.The yellow grips are made of coloured lovocom 1106-8085/yl- compounds based on pei (polyetherimide).Batch history review: the device quality and manufacturing history records have been checked for all available lot numbers and found to be according to our specifications valid at the time of production.No similar incidents have been filed with products from these batches.Conclusion and root cause: based on the information available as well as a result of our investigation, the root cause of the failure is most probably design related.Rationale: the selection of the material lovocim for this kind of instrument is questionable, since there are repeated problems with this kind of plastic during and after the processing process.The lifting of the grips and the shear breakage of the limitation stops are signs of a shrinkage of the material.Different thermal expansions of the different materials most likely caused a tensile stress above the tensile strenghth.Presumably, exposure time in combination with temperature during the reprocessing led to the tensile stress.Corrective action: a capa regarding the material of the grips has already been initiated and is ongoing.
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