Resumen de Relationship Between Implant Stability Measurements Obtained by Two Different Devices: A Systematic Review
Agda Marobo Andreotti, Marcelo Coelho Goiato, Adhara Smith Nobrega, Emily Vivianne Freitas da Silva, Humberto Gennari Filho, Eduardo Piza Pellizzer, Daniela Micheline Dos Santos
Background: The aim of this systematic review is to evaluate the relationship between two methods used to assess implant stability, investigating whether both provide similar implant stability assessments for the same clinical case.
Methods: A literature search was conducted on MEDLINE-PubMed and Scopus databases, without limitation of the publication period, up to November 2015. The following key words were used, with associations among them: “dental implant,” “dental implants,” “Osstell,” “resonance frequency analysis,” “implant stability quotient,” “ISQ,” “Periotest,” “Periotest value,” and “PTV.” Inclusion criteria were English language, prospective, retrospective, and randomized controlled clinical trials that evaluated implant stability through use of resonance frequency analysis (RFA) and damping capacity analysis (DCA). The study should assess implant stability of only a specific region for all patients or discriminate results evaluated for each region if the analysis had been made in various regions; RFA and DCA should have been applied in the same implants and periods. Studies have been carefully selected, and data of interest were tabulated.
Results: Six studies met the inclusion criteria. Although there was significant numerical correlation between values obtained by both methods, data showed that less than half (46%) of cases coincided in relation to implant stability classification.
Conclusions: It can be considered that there is not always a consensus and standardization in the classification of implant stability related to the values obtained by RFA and DCA devices, which could create disagreements and miscommunication among dentistry professionals.
Implant stability may be considered a clinical condition of absence of mobility1 and is defined as the ability to support axial, lateral, and rotational loads.2,3 Primary stability, which is one of the most important criteria for integration and successful healing, depends mainly on implant design (length, diameter, shape, and threads), in addition to surgical technique, volume, and mechanical quality of local bone.4,5 During the osseointegration process, bone is gradually remodeled to the threads of the implant, and thus secondary stability is achieved through direct bone–implant contact.6 Some methods and techniques for measuring implant stability involve non-invasive quantitative analyses, do not damage the bone–implant interface, and measure implant stability objectively, for example, resonance frequency analysis (RFA) and damping capacity analysis (DCA).1,2,7 These devices allow the monitoring of implant stability at any stage of treatment and in different observation periods.7 Several studies have investigated RFA and DCA regarding their ability to measure implant stability and have confirmed their usefulness for this purpose.8-10 In the RFA method, a “smartpeg” sensor is coupled to the implant, and subsequently the tip of the device is kept close to the sensor in the bucco-lingual and mesio-distal directions during the period of electromagnetic pulse emission. After this period, resonance frequency values are automatically converted into an arbitrary scale called the implant stability quotient (ISQ) and shown on the device display. ISQ values range from 1 to 100, and the higher the ISQ, the greater the implant stability.11 According to the device manufacturer,† and based on >700 references, an ISQ >70 represents “high stability,” and ISQ from 60 to 69 indicates “medium stability,” and an ISQ <60 is considered “low stability.”12 DCA is evaluated through an electronic instrument designed to measure the damping characteristics of the periodontal ligament of the teeth and evaluate their mobility.3 Currently, it is also used to evaluate implant stability.12 This device comprises a handpiece containing a metal “slug” that is accelerated toward the tooth/implant 16 times in 4 seconds. Results are represented as Periotest values (PTVs) ranging from −8 to 50,3 being determined by the contact time between the device and tooth/implant surface.7 Negative PTVs indicate greater implant stability.13 According to guideline values provided by the electronic page of the device manufacturer,‡ PTVs from −8 to 0 represent good osseointegration and “high stability,” values from 1 to 9 are considered “medium stability,” and values from 10 to 50 represent insufficient stability and dictate the implant should not be loaded (“low stability”).
Although both methods are used to measure implant stability, correlation and reliability between ISQs and PTVs is still a controversial issue,14 as some studies have shown a strong correlation between ISQs and PTVs,15 whereas others have shown no correlation.16 The aim of this systematic review was to assess the supposed relationship between the methods concerned, investigating whether both provide similar assessments of implant stability for the same clinical case, seeking thereby to avoid discrepancies and to facilitate communication between dentistry professionals.
