REVIEW ANALYSIS & EVALUATION ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION Systematic review of mini-implant displacement under orthodontic loading. Nienkemper M, Handschel J, Drescher D. Int J Oral Sci 2014;6:1–6.
REVIEWER Mohammed Khalil Al-Dhubhani, BDS, MSc Ortho
PURPOSE/QUESTION What is the short- or long-term effect of orthodontic force on the position of the miniscrews (MS) used in orthodontic treatment?
SOURCE OF FUNDING
Modest Evidence Indicates That Orthodontic Force Results in Positional Changes of Orthodontic Miniscrews SUMMARY Selection Criteria PubMed and Scopus databases were searched up to July 2013 for all papers investigating the stability of MS. Several combinations of terms were used for the MS (mini-implant OR miniscrew OR bone screw AND orthodontics AND displacement). All research designs except case reports and review articles were included. The articles sought had to have clear study design and reproducible measuring methods for determining the displacement of MS and be published in the English or German language. Sixty-eight articles were identified; of those, 26 articles met all inclusion and exclusion criteria. One additional article was retrieved by hand search, for a total of 27 articles included in the systematic review. The included articles were divided into two groups: (1) those investigating primary displacement (n = 16), which included 9 in vitro articles and 7 articles using finite element analysis; and (2) articles investigating secondary displacement of MS (n = 11), which included 9 clinical trials and 2 animal experiments.
Information not available
Key Study Factor TYPE OF STUDY/DESIGN
The key study factor was orthodontic force.
Systematic review
Main Outcome Measure
LEVEL OF EVIDENCE
The main outcome was either primary (early) displacement of MS (immediate displacement after applying force due to bone properties) or secondary displacement (long-term displacement due to bone remodeling) measured in millimeters.
Level 2: Limited-quality, patientoriented evidence
Main Results STRENGTH OF RECOMMENDATION GRADE Grade B: Inconsistent or limitedquality patient-oriented evidence
All but one of the included studies reported various ranges of primary and secondary displacement of MS loaded with normal orthodontic force (0.5–2.5 N). The results of the review indicate the diameter of the MS, insertion site, and loading duration as the most important factors determining the amount of displacement. The magnitude of force appeared to play a minor role if it remained within the range of normal orthodontic forces. No difference was found between self-tapping and self-drilling MS. The most common type of movement was controlled tipping or bodily movement, with greater displacement of the head area (1.0–4.1 mm) toward the side of applied force.
Conclusions J Evid Base Dent Pract 2014;14:118-119 1532-3382/$36.00 Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jebdp.2014.07.001
The authors concluded that the MS offer good anchorage for orthodontics biomechanics. Primary displacement was small (#0.1 mm) and clinically insignificant in nearly all studies. However, secondary displacement reached a clinically significant level (mean of 0–2.7 mm, with maximum values up to 5.5 mm).
JOURNAL OF EVIDENCE-BASED DENTAL PRACTICE
COMMENTARY AND ANALYSIS The use of MS has dramatically expanded previous orthodontic treatment expectations and shifted the quest for proper biomechanics toward a better, easier, and more efficient procedure in carefully selected cases. However, such advantages should not obscure the necessity for correct treatment planning. In addition, biological limitations must be respected and properly evaluated with close monitoring of any complications that might arise. In this systematic review, the authors addressed one of the overlooked MS complications, namely, displacement of MS under orthodontic forces. Only 8 uncontrolled trials and one randomized clinical trial provided adequate statistics. In contrast to conventional dental implants, MS were reported to show some positional changes under orthodontic forces (0.5–2.5 N).1,2 In addition to bone properties and remodeling, such instability might be attributed to the partial osseointegration observed in MS.3 The authors did not differentiate precisely between primary and secondary displacement in terms of time because it is possible for MS to show bony remodeling and tilting at the same time as a result of bone elasticity. Therefore MS might exhibit both types of displacement at the same time and it is not clinically feasible to differentiate between the two.
Volume 14, Number 3
Two other limitations were noticed. First, only two databases were searched (PubMed and Scopus). Second, only papers published in English or German were considered for review, which may have introduced a language bias. The authors favored a customized insertion of MS in the inter-radicular bone away from the direction of force to avoid root proximity and reduce MS failure rates. No further recommendations were given because of the lack of robust evidence. Further research is needed.
REFERENCES 1. Liou EJ, Pai BC, Lin JC. Do miniscrews remain stationary under orthodontic forces? Am J Orthod Dentofacial Orthop 2004;126(1):42-7. 2. Wang YC, Liou EJ. Comparison of the loading behavior of self-drilling and predrilled miniscrews throughout orthodontic loading. Am J Orthod Dentofacial Orthop 2008;133(1):38-43. 3. Deguchi T, Takano-Yamamoto T, Kanomi R, Hartsfield JK Jr, Roberts WE, Garetto LP. The use of small titanium screws for orthodontic anchorage. J Dent Res 2003;82:377-81.
REVIEWER Mohammed Khalil Al-Dhubhani, BDS, MSc Ortho Private practice, Al-Nasr Street, Sana’a, Yemen, Tel.: þ967 739375836 [email protected]
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REVIEWER Mohammed Khalil Al-Dhubhani, BDS, MSc Ortho
PURPOSE/QUESTION What is the short- or long-term effect of orthodontic force on the position of the miniscrews (MS) used in orthodontic treatment?
SOURCE OF FUNDING
Modest Evidence Indicates That Orthodontic Force Results in Positional Changes of Orthodontic Miniscrews SUMMARY Selection Criteria PubMed and Scopus databases were searched up to July 2013 for all papers investigating the stability of MS. Several combinations of terms were used for the MS (mini-implant OR miniscrew OR bone screw AND orthodontics AND displacement). All research designs except case reports and review articles were included. The articles sought had to have clear study design and reproducible measuring methods for determining the displacement of MS and be published in the English or German language. Sixty-eight articles were identified; of those, 26 articles met all inclusion and exclusion criteria. One additional article was retrieved by hand search, for a total of 27 articles included in the systematic review. The included articles were divided into two groups: (1) those investigating primary displacement (n = 16), which included 9 in vitro articles and 7 articles using finite element analysis; and (2) articles investigating secondary displacement of MS (n = 11), which included 9 clinical trials and 2 animal experiments.
Information not available
Key Study Factor TYPE OF STUDY/DESIGN
The key study factor was orthodontic force.
Systematic review
Main Outcome Measure
LEVEL OF EVIDENCE
The main outcome was either primary (early) displacement of MS (immediate displacement after applying force due to bone properties) or secondary displacement (long-term displacement due to bone remodeling) measured in millimeters.
Level 2: Limited-quality, patientoriented evidence
Main Results STRENGTH OF RECOMMENDATION GRADE Grade B: Inconsistent or limitedquality patient-oriented evidence
All but one of the included studies reported various ranges of primary and secondary displacement of MS loaded with normal orthodontic force (0.5–2.5 N). The results of the review indicate the diameter of the MS, insertion site, and loading duration as the most important factors determining the amount of displacement. The magnitude of force appeared to play a minor role if it remained within the range of normal orthodontic forces. No difference was found between self-tapping and self-drilling MS. The most common type of movement was controlled tipping or bodily movement, with greater displacement of the head area (1.0–4.1 mm) toward the side of applied force.
Conclusions J Evid Base Dent Pract 2014;14:118-119 1532-3382/$36.00 Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jebdp.2014.07.001
The authors concluded that the MS offer good anchorage for orthodontics biomechanics. Primary displacement was small (#0.1 mm) and clinically insignificant in nearly all studies. However, secondary displacement reached a clinically significant level (mean of 0–2.7 mm, with maximum values up to 5.5 mm).
JOURNAL OF EVIDENCE-BASED DENTAL PRACTICE
COMMENTARY AND ANALYSIS The use of MS has dramatically expanded previous orthodontic treatment expectations and shifted the quest for proper biomechanics toward a better, easier, and more efficient procedure in carefully selected cases. However, such advantages should not obscure the necessity for correct treatment planning. In addition, biological limitations must be respected and properly evaluated with close monitoring of any complications that might arise. In this systematic review, the authors addressed one of the overlooked MS complications, namely, displacement of MS under orthodontic forces. Only 8 uncontrolled trials and one randomized clinical trial provided adequate statistics. In contrast to conventional dental implants, MS were reported to show some positional changes under orthodontic forces (0.5–2.5 N).1,2 In addition to bone properties and remodeling, such instability might be attributed to the partial osseointegration observed in MS.3 The authors did not differentiate precisely between primary and secondary displacement in terms of time because it is possible for MS to show bony remodeling and tilting at the same time as a result of bone elasticity. Therefore MS might exhibit both types of displacement at the same time and it is not clinically feasible to differentiate between the two.
Volume 14, Number 3
Two other limitations were noticed. First, only two databases were searched (PubMed and Scopus). Second, only papers published in English or German were considered for review, which may have introduced a language bias. The authors favored a customized insertion of MS in the inter-radicular bone away from the direction of force to avoid root proximity and reduce MS failure rates. No further recommendations were given because of the lack of robust evidence. Further research is needed.
REFERENCES 1. Liou EJ, Pai BC, Lin JC. Do miniscrews remain stationary under orthodontic forces? Am J Orthod Dentofacial Orthop 2004;126(1):42-7. 2. Wang YC, Liou EJ. Comparison of the loading behavior of self-drilling and predrilled miniscrews throughout orthodontic loading. Am J Orthod Dentofacial Orthop 2008;133(1):38-43. 3. Deguchi T, Takano-Yamamoto T, Kanomi R, Hartsfield JK Jr, Roberts WE, Garetto LP. The use of small titanium screws for orthodontic anchorage. J Dent Res 2003;82:377-81.
REVIEWER Mohammed Khalil Al-Dhubhani, BDS, MSc Ortho Private practice, Al-Nasr Street, Sana’a, Yemen, Tel.: þ967 739375836 [email protected]
119
