In this video, Dr. Fields replaces a fractured implant from another company and replaces it with the new Screw-Retained Tissue Level Implant.

Full Case Summary: A healthy 41yo patient presents with a ceramic implant in the mandibular left first molar area that has fractured under occlusal function. The implant was not placed by us and is not a system that we use, though the problem is most likely not due to the specific implant system, but poor planning. Secondly, based on extensive ceramic implant experience, inattention to occlusion and poor crown design are likely additional failure factors, though we have no way of verifying this with certainty given the patient’s presenting condition to our office.

The implant that fractured is a 4.1mm diameter ceramic implant. Immediately we can see that we have at least 11.3mm between the 2 adjacent teeth. 11.3mm minus 4.1mm equals 7.2mm. Divide that by 2 for mesial space and distal space, and you get a crown that is overhanging the structural implant by 3.6mm on both the mesial and distal sides IF the implant is placed perfectly centered between adjacent teeth. Any buccal or lingual angulation offset from loading the implant down its long axis, and this implant has no chance of success (and this implant was angled far more to the lingual than is desirable)

A reasonable recommendation is to allow no more than 2mm of crown overhang from any ceramic implant to avoid shear loading and fracture. Question: why not place the largest diameter implant possible in a site this big when ridge width will accommodate any reasonable diameter implant? This implant system has a 4.8mm implant, so why was that not used? There is no good answer to these questions. In other words, such a narrow implant in such a large space to replace a molar is a very poor choice. Ceramic implant surgery is all about planning and precision. This case demonstrates neither.

In short, we trephined out this implant with the narrowest possible trephine, then drilled apically several additional millimeters, since we had available space above the inferior alveolar nerve. We used this extra length to achieve improved apical stability for an osteotomy that was dictated by the trephine diameter and was wider than ideal for replacement with a 5mm Z5TL Z-Systems implant with a 6mm diameter collar. This still gives us an implant diameter that is less than ideal, but with occlusal support both mesial and distal to this implant, we can take the crown slightly out of occlusion, limit cusp height, and do well: as long as our implant is well-centered and properly positioned. We corrected the lingual inclination of the previous implant when we extended the length of the osteotomy. 11-12mm molar spaces are most challenging because they are wider than ideal for the available implant diameters, and they are too narrow for placing multiple implants, even if you go to narrower diameter implants.