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Updated: May 10, 2026
09:41
A Simple Critical-sized Femoral Defect Model in Mice
Published on: March 15, 2015
A systematic review on the critical size defect model.
André Vajgel1, Nikos Mardas, Bruna Carvalho Farias
1Oral and Maxillofacial Department, University of Pernambuco (FOP/UPE), Recife, Brazil; CAPES Foundation, Ministry of Education of Brazil, Brasília, Brazil; Periodontology Unit, UCL Eastman Dental Institute, London, UK.
Clinical Oral Implants Research
|June 8, 2013
Summary
A 5.0 mm calvarial defect in adult rats can be considered a critical size defect (CSD). Further standardization of the rat calvaria model is needed for improved study comparisons.
Area of Science:
- Biomaterials Science
- Regenerative Medicine
- Surgical Research
Background:
- The critical size defect (CSD) model in adult rat calvaria is widely used in bone regeneration research.
- Defining the precise dimensions of a CSD is crucial for standardizing preclinical studies.
- Variability in CSD models can impact the interpretation of bone regeneration outcomes.
Purpose of the Study:
- To systematically review existing literature on critical size defects in adult rat calvaria.
- To identify specific defect dimensions that consistently represent a critical size.
- To assess the variability and heterogeneity in current rat calvaria defect models.
Main Methods:
- Comprehensive literature search of Ovid Medline and Embase databases up to July 2012.
- Inclusion of studies reporting complete defect closure or percentage of new bone formation (%NBF).
- Independent and duplicate screening, data extraction, and quality assessment of selected studies.
Main Results:
- Analysis of 61 studies, encompassing 937 defects, revealed spontaneous complete closure in only 14 defects.
- Defects with diameters of 5.0 mm and 6.0 mm showed minimal spontaneous closure (7 and 6 defects, respectively).
- Significant heterogeneity was observed in the percentage of new bone formation (%NBF) across different defect sizes and time points, with 5.0 mm defects showing variable %NBF (e.g., 18.29% at 1 month, 21.44% at 3 months).
Conclusions:
- Calvarial defects with a 5.0 mm diameter in adult rats can be classified as critical size defects (CSDs).
- The study highlights considerable variability in preclinical models, necessitating further standardization.
- Standardization of the rat calvaria model is essential for reliable comparisons in future bone regeneration research.
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