Healing of extraction sockets and surgically produced - augmented and non-augmented - defects in the alveolar ridge. An experimental study in the dog

• Published in: Journal of clinical periodontology 2005-05, Vol.32 (5), p.435-440
• Main Authors: Cardaropoli, G., Araújo, M., Hayacibara, R., Sukekava, F., Lindhe, J.
• Format: Article
• Language: English
• Subjects: Alveolar Process; Alveolar Process - physiology; Alveolar Process - surgery; Alveolar Ridge Augmentation; Alveolar Ridge Augmentation - methods; Animals; biomaterial; bone defect; bone formation; Bone Marrow; Bone Marrow - physiology; Bone Matrix; Bone Matrix - transplantation; Bone Regeneration; Bone Substitutes; Cattle; Dentistry; Dogs; extraction socket; grafting; Mandible; methods; Minerals; Odontologi; Periodontal Ligament; Periodontal Ligament - physiology; physiology; surgery; Tooth Socket; Tooth Socket - physiology; transplantation; Wound Healing; Wound Healing - physiology
• ISSN: 0303-6979; 1600-051X
• DOI: 10.1111/j.1600-051X.2005.00692.x

Objectives: The current experiments had three aims (i) to determine whether the absence of the periodontal ligament (PDL) may alter features of the healing of an extraction socket, (ii) to examine if there were differences in the proportion of different tissues in resolved extraction sockets and surgically produced defects after 3 months of healing, (iii) to study the influence of different biomaterials on the healing of surgically produced bone defects. Material and Methods: Extraction sites: In five dogs, the 4th mandibular pre‐molars were hemi‐sected and the distal roots were removed. The extraction socket of one of the pre‐molars was instrumented to eliminate all remnants of the PDL tissue. The socket of the contra‐lateral pre‐molar was left without instrumentation. The dogs were sacrificed after 3 months of healing. Defect sites: In five dogs, the pre‐molars and 1st molars on both sides of the mandible were first removed and 3 months of healing allowed. After this interval three standardized cylindrical defects were prepared in each side of the mandible. The defects were 3.5 mm in diameter and 8 mm deep. In each quadrant one defect was grafted with Bio‐Oss® Collagen, one with Collagen Sponge and one defect was left non‐grafted. The dogs were sacrificed 3 months after the grafting procedure. Results: Extraction sites: The two categories of extraction sockets did not differ with respect to gross morphological features. The tissue of the extraction sites, apical of a newly formed bone bridge, was dominated by bone marrow. Few trabeculae of lamellar bone were also present. Defect sites: The non‐augmented defect was sealed by a hard‐tissue bridge. In the central and apical portions of the defect bone marrow made up about 61%, and mineralized bone 39% of the tissues. The invagination of the surface of this crestal bone was 0.8±0.3 mm. The defect augmented with Collagen Sponge was covered by a hard‐tissue bridge 38% of the tissue within the defect was made up of bone marrow while the remaining 62% was occupied by mineralized bone. The invagination of the hard‐tissue bridge was on the average 0.6±0.1 mm. In defects augmented with Bio‐Oss® Collagen the biomaterial occupied a substantial portion of the tissue volume. Eighty‐five percent of the periphery of the Bio‐Oss® particles were found to be in direct contact with newly formed mineralized bone. Woven bone and bone marrow made up 47% and 26% of the newly formed tissue. The invagination of the most coronal pa