Effect of implant neck design on primary and secondary implant stability in the posterior maxilla: A prospective randomized controlled study

Abstract

Objective To compare the early changes in implant stability of implants with different neck design during the first 3 months of healing in the posterior maxilla. Materials and methods Patients were randomized to receive triangular neck implant (test), or round neck implant (control). Resonance frequency analysis (ISQ) measurements were obtained at surgery and at 2, 4, 7, 14, 21, 28, 45, 60, and 90 days following implant placement. Non‐parametric statistic was used for data analysis. Results Thirty‐two patients were included (17 test and 15 controls). Initial ISQ values of the test implants were high (mean: 68.4, SD = 8.4) and increased over time (mean: 74.4, SD = 6.0). Control implants presented a statistically significant higher initial ISQ value at implant placement (mean: 76.9, SD = 8.7), which was maintained over the healing period (mean: 77.6, SD = 3.6) with no significant changes between time intervals. After 6 weeks of healing, both implants displayed comparable ISQ values with no differences between the groups. All implants exhibited a decrease in stability on days 2 and 21 post‐placement. All roundneck implants used, and 82% of the triangularneck implants showed initial ISQ values above the suggested threshold for immediate loading (>60). Conclusions Implant neck design plays a role in implant primary stability in the posterior maxilla. Both implants show high primary stability, with significantly higher values for the round neck. However, these differences disappeared after 6 weeks of healing. While primary implant stability is partially governed by implant neck design, the role of this result is negligible for the achievement of secondary stability.

Dental Implants with Different Neck Design: A Prospective Clinical Comparative Study with 2-Year Follow-Up

“…According to Eshkol-Yogev et al [44], round neck implants may significantly increase primary stability when compared to triangular neck design. In a paper by Mendoca et al [45], bone remodeling showed to be of benefit around implants with rough collar design, in mandible but not in maxilla, if compared to machined collar surface implants.…”

Factors Affecting Implant Stability Quotients at Immediately and Conventionally Loaded Implants in the Posterior Maxilla: A Split‐Mouth Randomized Controlled Trial

“…4 RFA recordings are significantly affected by multiple factors including: (1) patient-related factors, i.e., gender and jaw shape; 5 (2) site-related factors, i.e., bone quality, bone density, trabecular thickness, cortical thickness, apical and crestal cortical anchorage, and implant position (anterior or posterior/maxilla or mandible); [5][6][7][8][9] (3) implant-and interlocking structures-related factors, i.e., implant design, implant microtopography, implant length and diameter, supracrestal implant length, and abutment height; 4,5,[10][11][12][13] (4) surgery-related factors, i.e., preparation of the implant site, and surgeon's experience; 14,15 (5) loading-related protocols; 16,17 (6) localization, type, width, and depth of peri-implant defects; 18 and (7) measurement-related factors, i.e., type of transducer, peg material, its point of application, its inclination relative to the peg, abutment height, and measurement directions (bucco-palatal, palato-buccal, mesio-distal, or disto-mesial). [19][20][21][22][23] Although numerous prospective clinical investigations have reported ISQ values of implants placed in the posterior maxilla without bone augmentation procedures, 11,12,16,[24][25][26][27][28] a limited number of studies have documented primary and secondary stability achieved by variable-thread tapered implants in simulated low-to medium-density bone, and none in nonregenerated posterior maxillary bone under clinical conditions. 29,30 A split-mouth randomized controlled trial (RCT) was conducted in 26 patients with bilateral partial maxillary posterior edentulism provided with variable-thread tapered implants placed in healed sit...…”

“…Although numerous prospective clinical investigations have reported ISQ values of implants placed in the posterior maxilla without bone augmentation procedures, 11,12,16,24–28 a limited number of studies have documented primary and secondary stability achieved by variable‐thread tapered implants in simulated low‐ to medium‐density bone, and none in nonregenerated posterior maxillary bone under clinical conditions 29,30 …”

Comparison of nonself‐tapping tapered implant and self‐tapping hybrid implant in terms of implant stability at initial and second fixation: A prospective randomized clinical trial

“…RFA is used in many clinical studies because of its minimally invasive nature and high reproducibility. [24][25][26][27] The ISQ value can be used to predict failure, and successful results can be obtained when the second stability value is 60 or more. 28,29 For RFA measurements, SmartPeg is installed on the platform, and the stable value for the implant is measured by determining the resonance frequency of the porcelain pulse applied to SmartPeg.…”

“…In this study, RFA was used to assess implant stability. RFA is used in many clinical studies because of its minimally invasive nature and high reproducibility 24‐27 . The ISQ value can be used to predict failure, and successful results can be obtained when the second stability value is 60 or more 28,29 .…”