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The aim of this study was to determine the stability of computer-aided design and manufacturing (CAD/CAM) and prefabricated abutment by measuring removal torque before and after cyclic loading.Three types of fixture and 2 types of abutments were used. Removable torque was measured after cyclic loading for 5000 cycles between 25 and 250 N for each group. The same procedure was performed twice.First, removal torque values (Newton centimeter) were measured for stock versus custom abutments as follows: group 1: 27.17 versus 26.67, group 2: 26.27 versus 26.33, and group 3: 37.33 versus 36.67. Second removal torque values (Newton centimeter) were also measured: group 1: 23 versus 23.5, group 2: 22.5 versus 22.33, and group 3: 32.67 versus 32.5. There was no significant difference between the stock and custom abutments in either the first or second removal torque values and also no significant difference among initial tightening torque, first or second removal torque (P0.05).With precise control of CAD/CAM abutments, good screw joint stability can be achieved.

This article reports the use of a customized surgical guide for simple and precise C-tube plate placement with minimized incision.Patients who were planning to have orthodontic miniplate treatment because of narrow interradicular space were recruited for this study. A combined silicone and stainless steel wire surgical guide for the C-tube was fabricated on the cast model. The taller wire of the positioning guide is used to accurately start the incision. The incision guide-wire position is verified by placing the miniplate on the coronal horizontal wire to confirm that the incision will coordinate with the screw holes. Because the miniplate is firmly held in place, there is no risk of the miniplate anchoring screws (diameter, 1.5 mm; length, 4 mm) sliding on the bone surface during placement with a manual hand driver.The surgical guide was placed on the clinical site, and it allowed precise placement of the miniplate with minimum incision and preventing from slippage or path-of-insertion angulation errors that might interfere with accurate placement.Customized surgical guide enables precise planning for miniplate positions in anatomically complex sites.