1
Jinsoo Yang
5th year, 14 gr
Osseointegration
Evaluation with ISQ
Method: a Systematic
Review
Master’s Thesis
Supervisor
DDS, PhD, Professor, Gintaras Juodzbalys
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Lithuanian University of Health Sciences, Kaunas, Lithuania. Department of Oral and Maxillofacial Surgery
Osseointegration Evaluation with ISQ Method: a Systematic Review
Master’s Thesis
The thesis was done
by student ... Supervisor ...
(signature) (signature)
... ...
(name surname, year, group) (degree, name surname)
... 20…. ... 20….
(day/month) (day/month)
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EVALUATION TABLE OF THE MASTER’S THESIS
OF THE TYPE OF SYSTEMIC REVIEW OF SCIENTIFIC LITERATURE
Evaluation: ...
Reviewer: ...
(scientific degree. name and surname)
Reviewing date: ...
No. MT parts MT evaluation aspects
Compliance with MT requirements and evaluation Yes Partially No 1 Summary (0.5 point)
Is summary informative and in compliance with the
thesis content and requirements? 0.3 0.1 0
2 Are keywords in compliance with the thesis
essence? 0.2 0.1 0
3 Introduc- tion, aim and tasks (1 point)
Are the novelty, relevance and significance of the
work justified in the introduction of the thesis? 0.4 0.2 0
4 Are the problem, hypothesis, aim and tasks formed
clearly and properly? 0.4 0.2 0
5 Are the aim and tasks interrelated? 0.2 0.1 0
6 Selection criteria of the studies, search methods and strategy (3.4 points)
Is the protocol of systemic review present? 0.6 0.3 0
7
Were the eligibility criteria of articles for the
selected protocol determined (e.g., year, language, publication condition, etc.)
0.4 0.2 0
8
Are all the information sources (databases with dates of coverage, contact with study authors to identify additional studies) described and is the last search day indicated?
0.2 0.1 0
9
Is the electronic search strategy described in such a way that it could be repeated (year of search, the last search day; keywords and their combinations; number of found and selected articles according to the combinations of keywords)?
0.4 0.1 0
10
Is the selection process of studies (screening, eligibility, included in systemic review or, if
applicable, included in the meta-analysis)
described?
0.4 0.2 0
11
Is the data extraction method from the articles (types of investigations, participants, interventions, analysed factors, indexes) described?
0.4 0.2 0
12
Are all the variables (for which data were sought and any assumptions and simplifications made) listed and defined?
0.4 0.2 0
13 Are the methods, which were used to evaluate the
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information is to be used in data synthesis, described?
14 Were the principal summary measures (risk ratio,
difference in means) stated? 0.4 0.2 0
15 Systemiza- tion and analysis of data (2.2 points)
Is the number of studies screened: included upon assessment for eligibility and excluded upon giving the reasons in each stage of exclusion presented?
0.6 0.3 0
16
Are the characteristics of studies presented in the included articles, according to which the data were extracted (e.g., study size, follow-up period, type of respondents) presented?
0.6 0.3 0
17
Are the evaluations of beneficial or harmful outcomes for each study presented? (a) simple summary data for each intervention group; b) effect estimates and confidence intervals)
0.4 0.2 0
18
Are the extracted and systemized data from studies presented in the tables according to individual tasks?
0.6 0.3 0
19
Discussion (1.4 points)
Are the main findings summarized and is their
relevance indicated? 0.4 0.2 0
20 Are the limitations of the performed systemic
review discussed? 0.4 0.2 0
21 Does author present the interpretation of the
results? 0.4 0.2 0
22
Conclusions (0.5 points)
Do the conclusions reflect the topic, aim and tasks
of the Master’s thesis? 0.2 0.1 0
23 Are the conclusions based on the analysed material? 0.2 0.1 0
24 Are the conclusions clear and laconic? 0.1 0.1 0
25
References (1 point)
Is the references list formed according to the
requirements? 0.4 0.2 0
26
Are the links of the references to the text correct? Are the literature sources cited correctly and precisely?
0.2 0.1 0
27 Is the scientific level of references suitable for
Master’s thesis? 0.2 0.1 0
28
Do the cited sources not older than 10 years old form at least 70% of sources, and the not older than 5 years – at least 40%?
0.2 0.1 0
Additional sections, which may increase the collected number of points
29 Annexes Do the presented annexes help to understand the
analysed topic? +0.2 +0.1 0
30
Practical recommen-
dations
Are the practical recommendations suggested and
are they related to the received results? +0.4 +0.2 0
31
Were additional methods of data analysis and their results used and described (sensitivity analyses, meta-regression)?
5
*Remark: the amount of collected points may exceed 10 points.
Reviewer’s comments: 32
Was meta-analysis applied? Are the selected statistical methods indicated? Are the results of each meta-analysis presented?
+2 +1 0
General requirements, non-compliance with which reduce the number of points
33
General require- ments
Is the thesis volume sufficient (excluding annexes)?
15-20 pages (-2 points)
<15 pages (-5 points)
34 Is the thesis volume increased
artificially? -2 points -1 point
35 Does the thesis structure satisfy the
requirements of Master’s thesis? -1 point -2 points
36 Is the thesis written in correct language,
scientifically, logically and laconically? -0.5 point -1 points
37 Are there any grammatical, style or
computer literacy-related mistakes? -2 points -1 points
38 Is text consistent, integral, and are the
volumes of its structural parts balanced? -0.2 point -0.5 points
39 Amount of plagiarism in the thesis. >20%
(not evaluated) 40
Is the content (names of sections and sub- sections and enumeration of pages) in compliance with the thesis structure and aims?
-0.2 point -0.5 points
41
Are the names of the thesis parts in compliance with the text? Are the titles of sections and sub-sections distinguished logically and correctly?
-0.2 point -0.5 points
42 Are there explanations of the key terms
and abbreviations (if needed)? -0.2 point -0.5 points
43
Is the quality of the thesis typography (quality of printing, visual aids, binding) good?
-0.2 point -0.5 points
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TABLE OF CONTENTS
1. 1.1. 1.2 1.3 2. 3. 4. 5. 6. SUMMARY ... INTRODUCTION... MATERIAL AND METHODS………...………..………... Protocol and registration……… Focus questions... Inclusion and exclusion criteria……….Results……… Discussion ……… ACKNOWLEDGMENTS AND DISCLOSURE
STATEMENTS ... REFERENCES... ANNEXES... 7 8 9 9 9 11 13 17 18 19 20
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Summary
Objectives: The purpose of the present study is investigating the principle and procedure of implant
stability quotient method and more information about osseo-integration evaluation.
Material and Methods: In this literature review literatures has been searched using Pubmed and other
sources using the searching with keywords: osseo-integration evaluation, ISQ method, implant, magnatic
resonance, Resonance frequency and resonance frequency analysis.
Results: This study compared implant stability quotient values among different method such as Periotest,
Osstell mentor, Osstell ISQ. There were small differences among all the values but ISQ method was the most precise and easiest method to evaluate osseo-integration.
Conclusions: In implantology stability between bone and implant is the most important problem.
Therefore many researchers and doctors are studying and doing experiment for new method for osseointegration evaluation these days. Implant stability quotient (ISQ) is one of the newest and effective methods used in osseotintegration evaluation.
Key words: Dental implants, magnatic resonance, ISQ method, resonance frequency analysis, osseointegration, primary bone stability.
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INTRODUCTION
Dental implants are used to provide mechanical support for various dental prostheses, such as crowns, bridges, dentures, and orthodontic apparatuses. The basis for such a desired support function by an implant is its mechanical stability. This is generally described, as a function of time, as a primary and a secondary stability [1]. A dental implant can be defined as successful when it integrates into the surrounding tissues. This integration is termed osseo-integration, which was originally defined by Branemark et al. [2] in 1985 as direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant. More recently, osseo-integration has been defined as a process whereby clinically asymptomatic rigid fixation of alloplastic materials is achieved and maintained in the bone during functional loading. Several methods: histology and histomorphometry, insertion torque, removal torque, push-through and pull-through, radiographic assessment, Periotest ultrasonic method, and resonance frequency analysis have been proposed to determine implant stability clinically [3], [5]. One such method has been introduced in the past decade and has been reported to be evidence based and useful for determining implant stability. Resonance frequency analysis (RFA) gives a clinical measure of stability and presumed osseo-integraion of implant [4]. Resonance frequency analysis (RFA) is a non-invasive technique which makes it possible to determine primary stability immediately after placement, as well as secondary fixation after a period of healing. The technique is based on the measurement of the RF of a small piezoelectric transducer screwed to an implant or abutment [6]. A metal rod (a peg) is connected to the implant by means of a screw connection [3]. The tip of the device is kept close to the sensor in buccolingual and mesiodistal directions, during the period of electromagnetic pulses emission. After this period, the resonance frequency values are automatically converted into an arbitrary scale called Implant Stability Quotient (ISQ) and shown on the device display. The ISQ values range from 1to 100, and the higher the ISQ, the greater the implant stability [7]. The RFA system has been used frequently to evaluate dental implant stability. At the time of surgery,
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implant stability appears to be related to both the geometry of the implant and the anatomy of the bone. It was found that the initial ISQ values were a function of type and thus the geometry of implants [3].
According to thesis investigated for osseo-integration evaluation, ISQ value method is the most modern and well used method. The aim of this study was to investigate the principle and results of osseo-integration evaluation values and compare ISQ value with other methods such as Osstell mentor, Osstell ISQ, periotest and show efficacy of ISQ method.
MATERIAL AND METHODS
Protocol and registration
The methods of the analysis and inclusion criteria were specified in advance and documented in a protocol. The review was registered in PROSPERO, an international prospective register of systematic reviews.
The protocol can be assessed at:
http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42017059695
Focus questions
The aim of this review is to find answers from the data extracted from the current literature to the following questions:
1. What kind of method is the most efficient method among periotest, Osstell mentor and Osstell ISQ?
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2. Is there any differences in ISQ values among 3 different methods (Periotest, Osstell mentor and Osstell ISQ)?
Types of studies
The review included all human prospective and retrospective follow-up studies and Studies published on English language between 2006 and 2016 with comparing various evaluation methods for osseo-integration evaluation with ISQ value.
Information sources
A search was conducted on one database – MEDLINE (pubmed).
Population
Patients who have had implant treatment procedures and on whom at least two implant stability quotient (ISQ) methods have been used to measure bone stability.
Literature Search Strategy
The MEDLINE resource database was explored through advanced searches. The search terms those were used during the primary stage were as follows: “osseo-integration evaluation” OR “resonance frequency analysis” OR “resonance frequency” OR “ISQ method” OR “bone stability”.
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The resulting articles were independently subjected to clear inclusion and exclusion criteria by two reviewers. Reviewers compared decisions and resolved differences through discussion.
Inclusion and exclusion criteria
Inclusion criteria for the selection were:
• In vitro and/or in vivo studies in measuring ISQ values
• Studies using resonance frequency analysis for measuring ISQ values • Studies using comparative analysis of ISQ values
Exclusion criteria for the selection were:
• Resonance analysis has not been described. • Studies with nano-structure surface of implant.
• Studies with implant stability according to implant design and surgical technique. • Studies with granules or PRF in implants
• Studies which is showing one measuring methods for ISQ values
Data collection process
Data was independently extracted from reports in form of variables according the aim and themes of present review as listed on words.
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Data items
Data were collected from the included articles and arranged in the following fields: year, follow-up period, patient number, implant number, measurement method, ISQ values.
Risk of bias assessment
The risk of bias assessment of the included trials was undertaken independently and in duplicate by at least two reviewers as part of the data extraction process.
Synthesis of results
Relevant data of interest on the previously stated variables were collected and organised into table. (Table 1)
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Table 1.Demographic from the selected studies.
RESULTS
Study selection
Article review and data extraction were performed according to the PRISMA flow diagram. The initial search identified a total of 40 articles. Following the publication last 10 years, 33 potentially relevant articles were identified. Screening of the abstracts resulted in the selection of 33 publications for possible inclusion. The inclusion and exclusion criteria were applied to the 17 full-text articles. Finally,
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5 articles that met the predefined criteria were included in the systemic review.
Figure 1
Exclusion of studies
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reviewed in full. Preliminary exclusion during screening stage was made by the publication period which published last 10 years (n = 7). Secondary exclusion during stage was made by the titles relevancy with eligibility of articles (n = 17). During eligibility stage articles that did not meet the inclusion and exclusion criteria, where filtered as followed: Resonance analysis has not been described (n = 6), Studies with nano-structure surface of implant (n = 6), Studies with implant stability according to implant design and surgical technique (n = 4), Studies with granules or PRF (n = 1), Studies which is non-comparative analysis (n = 11). Finely 5 studies were included in present view.
Study characteristics
All 5 studies finally selected for the review were in vivo and in vitro studies published in English with description of resonance frequency analysis. Each study conducted in vitro experiment by doing implant on cow’s rib and measured bone stability by resonance frequency analysis when four studies conducted additional in vivo experiments.
The selected studies evaluated osseo-integration at different periods: immediately after implant placement, baseline period (different for each study), each 2hours in vitro experiment; 3 weeks, 6weeks, 12weeks, 5years after implant loading. The evaluation methods for osseo-integration were: periotest, Resonance frequency analysis (RFA) with Osstell, Osstell Mentor, Osstell ISQ (Table 1).
All the studies aimed to compare two different methods of osseo-integartion. Two studies compared between Priotest value and Osstell mentor value. Other two studies compared between Osstell mentor value and Osstell ISQ value. One study compared between electronic resonance frequency method and ISQ. Last one study compared between magnatic resonance frequency value (Osstell mentor) and electronic resonance frequency value (Osstell). (Table 1)
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Risk of bias within studies
The risk of bias that indicated within this article is collected and organised in Table 2.
Table 2. Bias summary
Study Incomp lete outcom e data Random sequenc e generati on Allocatio n conceal ment SELECTIV E REPORTI NG Incomp lete outcom e data Other source s of bias P. Valderrama et al [2] + + ? + + + Oh et al [8] + ? ? + + + O. Geckili et al [9] + + ? + + + Oh et al [14] + ? ? + + + R. Jaramilo et al [15] + - ? + + +
+ = low risk; ? = unclear risk; - = high risk
Results of individual studies
Results of individual studies are show in Table 1.
Synthesis of results
A total number of 80 implants in vitro and 303 implants in vivo were collected from 194 patients. The classification of osseo-integration methods was given according to the generation of each device which
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is Periotest, Osstell mentor and Osstell ISQ (Table 1).
Results by type of evaluation methods, regarding Periotest value, 4 values were classified as “high stability” (57%), 3 values as “medium stability” (43%), 0 value as “high stability” (0%). For values with Osstell, 0 value was classified as “high stability” (0%), 3 values as “medium stability” (75%), 1 value as “low stability” (25%). For values with Osstell Mentor, 16 values were classified as “high stability” (84%), 2 values as “medium stability” (11%), 1 value as “low stability” (5%). For values with Osstell ISQ, all the 8 values were classified as “high stability” (100%) (Table 1).
Regarding to comparing between the methods, there was agreement in 11 cases out of 19 cases (58%). Evaluation value with Osstell Mentor was higher than Periotest in 2 cases (11%). Evaluation value with Periotest was higher than Osstell Mentor For other 2 cases (11%). Evaluation value with Osstell Mentor was higher that Ostell in 4 cases (20%).
DISCUSSION
This study compared results of osseo-integration evaluation values with 4 different methods. Results of this review showed that about 58% of cases corresponded in implant stability classification. A factor that can influence these results relates to the fact that, when clinically using device, the examiner is limited by access, space, and patient cooperation [7].
Primitive methods such as percussion and mobility testing by application of lateral forces with mirror handles have been used to determine primary stability. More recent methods have involved measuring cutting torque resistance and insertion torque values, both of which lack repeatability. Reverse torque test are invasive and destructive, hence impractical in a clinical setting. Other techniques such as the Periotest and dental fine tester were primarily developed for use on natural teeth
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and are subjected to several variables, and hence questionable for accuracy and reliability. Histomorphometric and histologic analysis of the bone implant interface, while reliable, is not practical in a clinical setting. The need for a user friendly, non-invasive, reliable, and clinically applicable technique to measure implant stability lead to the development of resonance frequency analysis (RFA) by Meredith and co –workers in 1996. A commercially available electronic device, based on RFA, with the trade name OSSTELL, is used widely for clinical and experimental purposes [16].
The Periotest device was designed to measure the damping characteristics of the periodontium of teeth. A small pistil is accelerated toward the tooth, which is deflected depending on its periodontal situation. A piezoelectric crystal integrated in the head of the pistil is deformed by the contact with the tooth and generates an electric impulse. The contace time is calculated into Periotest values ranging from -8 to +50. Bragger et al. first used it to determine implant stability [10]. The lower values represent more rigidity [9].
RFA is a non-invasive objective testing modality of implant stability. The original electronic RFA device is able to distinguish implants placed in different bone qualities, and it has been used to evaluate the prognosis of implants with different designs and surface characteristics [8]. There is a newer magnetic resonance frequency analyser with a different mechanism of action. Several generations of products have seemed throughout the last years. First generation is Osstell, second generation (Osstell Mentor) and third generation (Osstell ISQ), they are wireless.
The correlation and reliability between PTV and ISQ values with several devices has been controversial issue. There is a lot of studies comparing values each other. This study aimed to compare correlations among 4 values with different method/ devices. The results of this study show that there was low coincidence between Periotest value and Osstell Mentor value, but there was high coincidence between Osstell Mentor value and Osstell ISQ value which are second and third generation of Osstell devices.
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both prefer. New systems and technologies have been investigating by many dentists and researchers. The osseo-integration evaluation methods also have been developed from using hands to measuring the values in digital machines. The developed methods are efficient for dentists and also patients. These facts shows us that there will be more useful and helpful methods will be developed as successor Osstell ISQ methods.
CONCLUSIONS
This study investigated four oseeo-integration evaluation methods which are Periotest, Resonance Frequency Analysis system Osstell, Osstell Mentor and Osstell ISQ in generation order. All the methods showed difference between each method except Osstell ISQ showed almost perfect coincindence with Osstell Mentor. Therefore, there is not exact correlation between each method. The results can be different according to several clinical conditions.
ACKNOWLEDGMENTS AND DISCLOSURE STATEMENTS
The authors report no conflicts of interest related to this study. The authors would like to thank Gintaras Juodzbalys (Lithuanian University of Health Sciences, Medical Academy) and Lukas Poškevičius (Lithuanian University of Health Sciences, Oral surgery department) for their help in editing this manuscript.
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REFERENCES
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2. Pilar Valderrama, Thomas W. Oates, Archie A. Jones, James Simpson, John D. Schoolfield, and David L. Evaluation of Two Different Resonance Frequency Devices to Detect Implant Stability: A Clinical Trial Cochran Journal of Periodontology 2007 78:2, 262-272 [Medline: 17274715][DOI 10.1902/jop.2007.060143] .
3. Rozé, J., Babu, S., Saffarzadeh, A., Gayet-Delacroix, M., Hoornaert, A. and Layrolle, P. (2009), Correlating implant stability to bone structure. Clinical Oral Implants Research, 20: 1140–1145. [Medline: 19519789][doi:10.1111/j.1600-0501.2009.01745.x]
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Relationship Between Implant Stability Measurements Obtained by Two Different Devices: A Systematic Review Journal of Periodontology 0 0:0, 1-13[Medline: 27767386][ DOI: 10.1902/jop.2016.160436]
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