Predicting osseointegration by means of implant primary stability

Abstract

The purpose of the present clinical study was (1) to evaluate the Osstell as a diagnostic tool capable of differentiating between stable and mobile ITI implants, (2) to evaluate a cut-off threshold implant stability quotient (ISQ) value obtained at implant placement (ISQitv) that might be predictive of osseointegration, (3) to compare the predictive ISQitv of immediately loaded (IL) implants and implants loaded after 3 months (DL). Two patient groups were enrolled, 18 patients received 63 IL implants and 18 patients were treated with 43 DL implants. The ISQ was recorded at implant placement, after 1, 2, 4, 6, 8, 10 and 12 weeks. All implants passed the 1-year loading control. Two implants failed, one DL implant with ISQ at placement (ISQi) of 48 and one IL implant with ISQi of 53. The resonance-frequency analysis (RFA) method was not a reliable diagnostic tool to identify mobile implants. However, implant stability could be reliably determined for implants displaying an ISQ> or =47. After 1 year of loading, all DL implants with an ISQi> or =49 and all IL implants with an ISQi> or =54 achieved and maintained osseointegration. By the end of 3 months, implants with ISQi<60 had an increase of stability. Implants with ISQi 60-69 had their stability decrease during 8 weeks before returning to their initial values. Implants with ISQ>69 had their stability decrease during the first 4 weeks before remaining stable. Although preliminary, these data might orient the practitioner to choose among various loading protocols and to selectively monitor implants during the healing phase.

Relationship between implant stability measurements obtained by insertion torque and resonance frequency analysis: A systematic review

“…33 Its determination could be relevant to the prognosis of the dental implant. 5 There is a gap in the literature about the relationship between these methods. The present systematic review showed no correlation between these measurements at the time of dental implant placement.…”

A Newly Designed Resonance Frequency Analysis Device for Dental Implant Stability Detection

“…However, it is somewhat inconvenient and time-consuming 17) , and it may even affect the implant-bone interface at the early healing stage. This is because the Osstell transducer must be screwed into the test implant with a torque of 10 N cm, almost half the force used to place an implant.…”

“…After testing 276 immediate loaded implants using RFA, Balshi et al suggested that bone types II and III were more consistent in term of stability return, while bone types I and IV were not 19) . Primary stability, a function of bone quality, implant design, and surgical procedure, is one of the important factors that influences the survival rate of implants 17,20,27) . It has been reported that primary stability can serve as a useful predictor of osseointegration 16) .…”

“…A number of researches have proposed that where the initial ISQ value is above 60, the implant is ready for immediate loading [17][18][19] . However, for implants with ISQ values below 40, this should serve as a warning of early failure 18) .…”

“…The resonance frequency value thus obtained is converted to give an Implant Stability Quotient (ISQ) for analyzing implant stability [9][10][11][12] . Recently, this device has been used in implant research to perform the following tasks: compare the success rates between conventional and early loading of implants [13][14] , evaluate the survival rates of transmucosal implants immediately restored with single crowns 15) , monitor the differences between immediate and standard delayed loading of implants [16][17][18] , profile physiological and geometric factors affecting immediate loaded implants [19][20] , and measure stability achieved with one-stage surgical procedures [21][22] . However, clinical investigation has indicated that temporary attachment, removal, and sterilization of the transducer are time-consuming and far from being cost-effective 17) .…”