Astra Tech Implants: Anyone Else Experience Flowering in the Top of the Implants?

Authors

I have been using Astra Tech implants quite successfully for some years now. Â Recently I have had several cases of Astra Tech implant fixtures experiencing a flowering [Editor’s note: fracturing within the coronal aspect]. Â I have just seen my third case of this happening in their 4.5mm diameter implant. Â The case involved screw retained crowns that had been functioning without any problems for 3 years. Â Could this have been due to an occlusal overload? Â Or is this a problem in implant design or flexural strength? Â I discussed this problem with Astra Tech and they say that this has been a rare event. Â Have any of you experienced this problem with their implant system?