Comparison of initial stability of mandibular first molar repaired with different threaded implants under immediate loading
- VernacularTitle:不同螺纹种植体修复下颌第一磨牙即刻负荷的初始稳定性比较
- Author:
Xinru LI
1
;
Wenbo ZHAO
;
Yan JI
;
Weiwei TENG
;
Yiming WANG
;
Libo ZHOU
Author Information
- Keywords: implant restoration; implant; immediate loading; threaded design; three-dimensional finite element analysis; initial stability
- From: Chinese Journal of Tissue Engineering Research 2024;28(22):3445-3450
- CountryChina
- Language:Chinese
- Abstract: BACKGROUND:The threaded conical implant has a good ability to control micro movements and is conducive to immediate loading.However,the effects of double-threaded conical cylindrical implants and conical cylindrical implants on stress distribution and initial stability of implant-bone interface after immediate loading have not been reported. OBJECTIVE:To investigate the impact of double-threaded conical cylindrical implants and conical cylindrical implants on the biological distribution of the implant and the surrounding bone interface during immediate loading in the mandibular molar region. METHODS:(1)Three-dimensional finite element analysis:Conical beam CT scans of the mandible and first molar of a volunteer were used to develop a basal model of the mandible.The double-threaded conical cylindrical implants and conical cylindrical implants were assembled with the mandibular models,and an immediate-load(or delayed implantation)implant model(a total of four models)for the first mandibular molar was established.Loads in four directions(100 N):axial,lingual and buccal 45°,mesial and distal,and buccal and lingual,were applied to the central fossa of each model's crown.Three-dimensional finite element method was used to analyze the implant displacement and the stress distribution at the implant-bone interface.(2)In vitro experiment:With the assistance of the oral implant robot,the double-threaded conical cylindrical implants and conical cylindrical implants were implanted on the same artificial bone pieces,separately,and the immediate load model of immediate implant implantation(or delayed implantation)was established in vitro(a total of four groups of models).Osstell resonance frequency analyzer and SmartPeg sensor were used to measure the implant stability coefficient in four vertical directions:front,rear,left,and right measurements,evaluate the initial stability,and verify the finite element analysis results. RESULTS AND CONCLUSION:(1)The displacement difference between double-threaded conical cylindrical implants and conical cylindrical implants was small when the immediate loading of delayed implantation was applied,but the maximum stress value of conical cylindrical implant-bone interface was greater than that of double-threaded conical cylindrical implant-bone interface.When the immediate loading of immediate implantation was applied,the maximum stress value and the maximum displacement of bone around the implant appeared when the load was applied in mesiodistal direction.The stress value of the conical cylindrical implant reached 298.84 MPa and the maximum displacement was 0.31 mm,both of which were larger than that of the double-threaded conical cylindrical implant.(2)The results of in vitro experiments showed that the stability coefficient of the double-threaded conical cylindrical implant was greater than that of the conical cylindrical implant.(3)Compared with the conical cylindrical implant,the double-threaded conical cylindrical implant has higher initial stability under immediate loading,suggesting that the use of double-threaded conical cylindrical implant should be given priority in clinical immediate loading.
