IADR Abstract Archives
Periodontal Regeneration in a Rat Model Using Self-Assembling Peptides
Objectives: To investigate the effects of a self-assembling peptide (SAP; P11-4) on periodontal regeneration in surgically-induced periodontal critical-sized defects in rats.
Methods: Twenty-six, bilateral maxillary critical periodontal defects (2 x 2 x 1.7 mm) were created surgically in 13 male Sprague Dawley rats. Defects on one side of the mouth were filled with pre-assembled P11-4 hydrogel; the contra-lateral defect was untreated (control). Rats were sacrificed immediately post-surgery (time 0) and after 2 and 4 weeks. Maxillae were retrieved, decalcified in 10% EDTA and processed for histological analysis, immunohistochemical determination of osteocalcin, osteoprotegrin, RANKL and PCNA and histomorphometric assessments.
Results: Both treated and untreated defects showed clear tissue regeneration at both time points compared to time 0. However, histological analysis showed greater organisation of periodontal fibers in defects treated with P11-4, at both time points, when compared to untreated defects. Histomorphometric analysis showed that treated defects had both a significant increase in functional periodontal ligament length and a reduction in epithelial down growth after 4 weeks compared to untreated defects. There was no significant difference in the relative alveolar bone height between treated and untreated defects at both time points. At 2 weeks, treated defects showed a significant increase in expression of osteocalcin and osteoprotegerin (OPG) as judged by immunohistochemistry. Treated defects also showed a significantly higher OPG/RANKL ratio compared to untreated defects, suggesting greater osteoblastic activity. PCNA and RANKL expressions at both time points showed no significant difference between treated and untreated defects.
Conclusions: The results suggest enhanced regeneration of periodontal tissues when SAP P11-4 was used to treat surgically-induced periodontal defects in rats. SAP P11-4 is currently used clinically to treat early caries, the findings of this study suggest its possible application in the treatment of periodontal disease.
Methods: Twenty-six, bilateral maxillary critical periodontal defects (2 x 2 x 1.7 mm) were created surgically in 13 male Sprague Dawley rats. Defects on one side of the mouth were filled with pre-assembled P11-4 hydrogel; the contra-lateral defect was untreated (control). Rats were sacrificed immediately post-surgery (time 0) and after 2 and 4 weeks. Maxillae were retrieved, decalcified in 10% EDTA and processed for histological analysis, immunohistochemical determination of osteocalcin, osteoprotegrin, RANKL and PCNA and histomorphometric assessments.
Results: Both treated and untreated defects showed clear tissue regeneration at both time points compared to time 0. However, histological analysis showed greater organisation of periodontal fibers in defects treated with P11-4, at both time points, when compared to untreated defects. Histomorphometric analysis showed that treated defects had both a significant increase in functional periodontal ligament length and a reduction in epithelial down growth after 4 weeks compared to untreated defects. There was no significant difference in the relative alveolar bone height between treated and untreated defects at both time points. At 2 weeks, treated defects showed a significant increase in expression of osteocalcin and osteoprotegerin (OPG) as judged by immunohistochemistry. Treated defects also showed a significantly higher OPG/RANKL ratio compared to untreated defects, suggesting greater osteoblastic activity. PCNA and RANKL expressions at both time points showed no significant difference between treated and untreated defects.
Conclusions: The results suggest enhanced regeneration of periodontal tissues when SAP P11-4 was used to treat surgically-induced periodontal defects in rats. SAP P11-4 is currently used clinically to treat early caries, the findings of this study suggest its possible application in the treatment of periodontal disease.