Abstract:

BACKGROUND: CAD-CAM template-guided flapless implantation can ensure reliable transfer of preoperative computer-assisted planning into surgical practice. A new type of template-guided flapless implant placement using a CAM model-based planning procedure can also be used in sites with insufficient bone volume．
OBJECTIVE: By observing the clinical results of flapless implant operation with implant navigation in the areas of maxillary premolar, which have relatively insufficient bone width, to evaluate the clinical feasibility of this method.
METHODS: A total of eight patients who had lost 10 maxillary premolars were treated with the operations. The average height of premolar alveolar bone was (13.45±1.67) mm. By using craniofacial CT scan, three-dimensional reconstruction analysis and sham-operated analysis of rapid prototyping models, we obtained the accurate datum of the length, width, height and angle of the alveolar bone. 
RESULTS AND CONCLUSION: The surgical guides had sufficient retention which was easy to place and remove on the teeth. Compared with the sham-operated analysis of models, all the implants of the 10 teeth had been implanted accurately. The average operation time was (17.0 ± 5.8) minutes. Except for one patient who had a residual root under the mucosa of maxillary sinus, the length of the implants in the alveolar bone was all more than 13 mm, without the occurrence of penetration of mucosa of maxillary sinus, perforation of bone lamella and other complications. And all the patients only had mild swelling and pain. Ten porcelain crowns were placed 3 to 6 months later. With the guidance of guide plates, the implants can be accurately implanted into the insufficient bone by application of flapless implant operation. This method may have great technical advantages and broad prospects in curing the patients with alveolar bone atrophy and insufficient available bone.