implants - the journal of oral implantology UK Edition

I case report_ Er:YAG lasers 12 I implants1_2012 above the head of the implant, an explorer, a straight probe or haemostats30 might be successful. The tip of the instrument is moved carefully in a counter-clock- wise direction over the surface of the screw segment until it loosens.1 If the screw fracture occurs below the headoftheimplant,othermethodsarerequired.There are several available implant repair kits: • ITI® Dental Implant System (Institut Straumann AG, Switzerland), consists of drills, two drill guides and six manual tapping instruments.8 • IMZ® TwinPlus Implant System1 DENTSPLYFriadent, Germany) • Screw Removal Kit Replace (Nobel Biocare™, Yorba Linda, California, USA) • Certain®-Screw Removal Kit (Biomet 3i™, Florida, USA31) The application of these systems is to permit a hole to be drilled into the centre of the broken screw and drive a removal wedge into the hole that engages the broken screw when reverse torque is applied by re- moving the instrument. If no thread damage has occurred and the screw has not “bottomed out” or torqued into a seating stop, then the force necessary to remove the screw may be minimal.8 If none of these systems is available, another method for broken screw retrieval involves the fol- lowing procedure: after the prosthesis or abutment is removed, the screw hole is vigorously flushed with an air/water spray from a 3-way syringe. Pressurised air is applied to dry the screw hole, and a drop of mineral oil (delivered on the tip of an explorer) is introduced into the screw hole. A sharp 1⁄4-round bur in a high- speed handpiece is activated and lightly applied to the exposed side of the fractured screw. The objective is to have the spinning bur’s blades contact the metal sur- face of the screw so that the screw will spin itself out of the hole. When repeated several times, the screw can be backed out and retrieved easily with forceps.8 If this technique fails, a slot can be created using a surgical drill, on the head of the fractured screw, and then a screwdriver is used to back out the bro- ken abutment screw. Sometimes just a gentle touch with the drill to the head of the broken screw will be enough to back it out. If the hexagonal head of the screw is stripped, it should be filed away completely using a round carbide bur or heatless stone, the head of the implant should be straightened, and a new abutment may be rotated into the implant. _Case study This clinical report describes a situation in which a fractured implant abutment screw was successfully retrieved by using the Er:YAG laser as an auxiliary tool, and the advantages of this 2,940nm wavelength ver- sus conventional methods. _Examination A 36-year-old male presented for treatment, re- porting the detachment of an implant-supported crown in the region of the upper left central incisor. The patient stated that the implant and crown had Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16