Influence of Implant Angulation and Implant Number on the Accuracy of Definitive Casts

Abstract

Background: The present study determined the effect of implant angulation and implant number on the dimensional precision of implant definitive casts. Materials and Methods: Three definitive casts with implant analogs placed in a triangular pattern were made from dental stone. Group I was control group, Group II in which implant numbers 1 and 3 were at 5° convergence to the implant number 2. Group III in which implant numbers 1 and 3 are at 5° divergence to the implant number 2. Group IV in which implant numbers 1 and 3 are at 10° convergence to the implant number 2. Implant analogs were secured in all the definitive casts with cyanoacrylate. Three open tray impressions of the definitive cast were obtained and poured in Type IV dental stone. Coordinates in the three planes were measured at implant analog top surface and base of the cast using a fine tip measuring stylus. The data were aligned and angular differences between implant analog vectors from definitive and duplicate casts were measured. Results: There was a significant correlation between dental implant number and dental implant angulation ( P < 0.05). There was a significant result when comparing the effect of the parallel group from 5° divergence and 10° convergence groups. A significant results while comparing the parallel group with 5° divergence and 10° convergence was obtained whereas while comparing 5° divergence, 5° divergence, and 10° convergence a nonsignificant difference was obtained ( P > 0.05). Conclusion: Close proximity of implant angulation toward right-angled direction results in higher precision of implant.

Effect of different fabrication workflows on the passive fit of screw-retained bar splinting two interforaminal implants: a parallel blinded randomised clinical trial

“…Furthermore, Rutkunas et al showed non statistically significant difference between both impression techniques on the passive fit of the implant supported restorations [ 25 ]. In another study, it was stated that the accuracy between both impression techniques was found to be comparable in the parallel placed implants; a further reason for the results in the current study as the implants were placed parallel by the help of surgical guides [ 6 , 28 ]. On the contrary, Roig et al, concluded that the fit of frameworks fabricated by the digital impression technique was better than the conventional one.…”

“…Such factors include the relative parallelism between the implants, implant number, impression material and technique, in addition to the method of prothesis fabrication [ 5 ]. In a study conducted by Narayane et al, they concluded that the more parallel the implants, the more accurate the impression with less deviation of the implant analogs [ 6 ]. Michelinakis et al also reported that less implant deviations were encountered in the short span edentulous sites with a smaller number of implants compared to the long span or the completely edentulous sites having a greater number of implants [ 7 ].…”

Evaluation of effect of implant angulation and implant number on the dimensional accuracy of definitive casts

“…We found that while analyzing the impact of dental implant number and the correlative effect between dental implant number and dental implant angulation, significant results were obtained (P< 0.05). Narayane et al 11 determined the effect of implant angulation and implant number on the dimensional precision of implant definitive casts. Three definitive casts with implant analogs placed in a triangular pattern were made from dental stone.…”