The Influence of Implant Shape on Primary Stability of Implants With a Thread Cutting and Forming Design: An Ex Vivo Study

Abstract

The design of an implant has a great effect on primary stability. The purpose of this study was to determine the differences in primary stability between straight and tapered Neoss ProActive implants in type I and type III bones using resonance frequency analysis (RFA) and electronic percussive testing (EPT) methods. Fresh cow vertebrae and pelvis were used as models of type III and type i bone, respectively. Implants of 2 different designs—straight and tapered Neoss ProActive implants with a thread cutting and forming (TCF) design, both 3.5-mm wide and 11-mm long—were placed in both types of bone (n = 60). The primary stability of all implants was measured by an experienced clinician blinded to the study protocol using the EPT and RFA devices. No statistically significant difference was found between the implant stability quotients and the percussive test values of straight and tapered implants in either bone type. Within the limitations of this ex vivo study, it may be concluded that the shape of an implant with a TCF design does not affect primary stability.

Primary stability of narrow‐diameter dental implants with a multiple condensing thread design placed in bone with and without osteotomes: An in vitro study

“…6 Other variables that may affect PS encompass implant dimensions (length and diameter), surface characteristics (moderately rough or smooth), and number of threads on the implant surface. 3,[7][8][9][10][11] With regard to implant diameter, studies [12][13][14][15] have shown that narrow-(<3.3 mm) and standard-(4.1 mm) diameter dental implants can remain functionally stable in smokers and medically compromised patient in a manner similar to systemically healthy nonsmokers. However, achievement of PS is often challenging when implants are placed in type-IV bone (soft bone), which usually comprises the posterior maxillae.…”

“…Moreover, tapered dental implants demonstrate a higher mechanical stability compared with cylindrical dental implants 6 . Other variables that may affect PS encompass implant dimensions (length and diameter), surface characteristics (moderately rough or smooth), and number of threads on the implant surface 3,7‐11 . With regard to implant diameter, studies 12‐15 have shown that narrow‐ (<3.3 mm) and standard‐ (4.1 mm) diameter dental implants can remain functionally stable in smokers and medically compromised patient in a manner similar to systemically healthy nonsmokers.…”

Considerations Regarding Dental Implant Site Preparation using Osseo densification Osteotomy. A Critical Review

“…Endosteal implants are anchored into bone tissue. Their long-term success and retention depend firstly on primary implant stability (PIS) and, ultimately, on the biological stability mediated by osseointegration (OI) [4][5][6][7][8][9]. PIS refers to the avoidance of micromovements at the implant-bone interface during early postoperative bone remodeling, which is determined by physical interactions of the implant with surrounding bone tissue [10].…”

“…PIS refers to the avoidance of micromovements at the implant-bone interface during early postoperative bone remodeling, which is determined by physical interactions of the implant with surrounding bone tissue [10]. It degrades gradually after the initial implant placement [4][5][6][7][8][9]. Meanwhile, a transition occurs wherein bone remodeling during OI -defined as the development of a mechanical connection between living bone tissue and an implant body -brings the implant surfaces into tight apposition with stabilizing bone tissue [4][5][6][7][8][9].…”

“…It degrades gradually after the initial implant placement [4][5][6][7][8][9]. Meanwhile, a transition occurs wherein bone remodeling during OI -defined as the development of a mechanical connection between living bone tissue and an implant body -brings the implant surfaces into tight apposition with stabilizing bone tissue [4][5][6][7][8][9]. Clinical OI research, translated from preliminary studies in animal models, has demonstrated that reduced cortical bone shell adheres to an implant directly (without interceding tissue) during postoperative immobilization [11][12][13][14].…”