Evaluation of the long-term stability of micro-screws under different loading protocols: a systematic review

Zhang, J. N. and Lu, H. P. and Bao, X. C. and Shi, Y. and Zhang, M. H.

Braz Oral Res (2019) 33: e046

DOI: 10.1590/1807-3107bor-2019.vol33.0046

Abstract

The aim of this systematic review was to investigate the association between the different factors of loading protocols and the long-term stability of micro-screws from biomechanical and histological viewpoints. Searches were performed on PubMed, Embase, Cochrane Library, Wanfang and CNKI databases for animal experiments comparing loading protocols and the long-term stability of micro-screws. Among 1011 detected papers, 16 studies met the eligibility criteria and were selected for analysis. Most studies showed medium methodological quality for evaluation of micro-screws’ long-term stability. Five studies reported that loading would not destroy the long-term stability of micro-screws. Three studies indicated that low-intensity immediate loading or a 3-week minimal healing time was acceptable. Two studies reported that the loading magnitude was a controversial issue with regard to the micro-screws’ long-term stability. Two studies suggested that counterclockwise loading could decrease the long-term stability of micro-screws. In conclusion, immediate loading below 100g force, healing time greater than 3 weeks, regular loading below 200g force and a clockwise direction of force supported the long-term stability of micro-screws. Further studies relating to the combination of varying loading conditions will be needed.

Citation

Zhang, J. N., Lu, H. P., Bao, X. C., Shi, Y., & Zhang, M. H. (2019). Evaluation of the long-term stability of micro-screws under different loading protocols: a systematic review. Braz Oral Res, 33, e046. https://doi.org/10.1590/1807-3107bor-2019.vol33.0046 Animals, Time Factors, Treatment Outcome, Models, Animal, Equipment Design, Wound Healing, Reference Values, Reproducibility of Results, Biomechanical Phenomena, Bone Screws/*standards, Dental Implantation/instrumentation/*methods, Dental Implants/*standards, Orthodontic Anchorage Procedures/instrumentation/*methods

Keywords

• Animals
• Time Factors
• Treatment Outcome
• Models
• Animal
• Equipment Design
• Wound Healing
• Reference Values
• Reproducibility of Results
• Biomechanical Phenomena
• Bone Screws/*standards
• Dental Implantation/instrumentation/*methods
• Dental Implants/*standards
• Orthodontic Anchorage Procedures/instrumentation/*methods