Análise da estabilidade de um implante Tissue-Level não auto-roscante em função de dois tipos de protocolos de fresagem
: estudo pré-clínico

  • José Rodrigues Gomes (Student)

Student thesis: Master's Thesis


Introduction: there are several methods for assessing the stability of implants, such as radiographic analysis, insertion torque analysis, reverse torque test and modal analysis, with Osstell® standing out in the latter. It is a device that uses the resonance frequency to measure the stability of the implant in ISQ values. Dental implants can be non-self-tapping or self-tapping, and their characteristics, such as macro and microgeometry, and surface, affect the biomechanics of osseointegration. This study aims to define a methodology for investigating the stability of implants in a preclinical environment and to compare the stability of non-self-tapping implants, of the tissue-level type, in different bone densities, with two different milling protocols. Materials and methods: two blocks of resin from the brand Bonemodels® were used to simulate four types of bone density (D1-D4). Thirty-two Straumann® Tissue-level SPØ4.1 RN, SLA® non-self-tapping implants were used, which were placed using two different milling protocols: Straumann® cylindrical vs. conical drills. After insertion, the maximum insertion torque and the ISQ value of the Osstell® system were recorded. The independent variables were bone density and drilling protocol. A descriptive and inferential statistical analysis of the obtained results was carried out. Results: the methodological protocol developed allowed obtaining ISQ measurement results and torque values of the placed implants. We found that implants in D4 bone had lower ISQ and torque values, as opposed to D1-D2-D3 bone. The values obtained in the “conical” milling protocol were higher than the values obtained in the conventional protocol. In the analysis of the total number of implants in each group, there was a statistically significant difference only in the ISQ-MD values (p<0.021), being higher in the test group.
Conclusion: within the limitations of this study, we can conclude that the experimental protocol presented here seems to be viable for future preclinical research studies. This study allowed assessing some methodological limitations that could be resolved in future studies. On cylindrical implants, the use of a milling protocol with conical drills resulted in greater implant stability compared to the conventional milling protocol.
Date of Award6 Oct 2023
Original languagePortuguese
Awarding Institution
  • Universidade Católica Portuguesa
SupervisorAndré Correia (Supervisor) & Rosemary Sadami Arai Shinkai (Co-Supervisor)


  • Milling protocols
  • Torque
  • Dental prosthesis
  • Dental implants
  • Implant stability
  • Bone quality


  • Mestrado em Medicina Dentária

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