Three days after a tooth extraction, something invisible begins to happen inside the wound. Collagen fibers—the most abundant structural protein in living organisms—begin weaving themselves together to form a new network. Yet the speed of this process, it turns out, depends on what is placed inside the socket left by the extracted tooth.
That is the essence of a study conducted by Prof. Dr. drg. Regina TC. Tandelilin, M.Sc., PBO., from the Department of Oral Biology, Faculty of Dentistry, Universitas Gadjah Mada. In her study, published in The Indonesian Journal of Dental Research, she demonstrated that augmentation using Demineralized Bone Matrix (DBM) powder—a bone graft material that has been demineralized and dried—significantly increased the density of gingival collagen fibers in the mandibles of rabbits following tooth extraction.
When a Wound Needs More Than Just Time
Tooth extraction is not a simple procedure without consequences. Beneath this seemingly routine procedure, the alveolus—the bone that supports the teeth—may be damaged. Mercier, one of the authorities in dental surgery, noted that bone abnormalities resulting from tooth extraction are among the most frequently encountered conditions in dental surgical practice.
To prevent further damage, one approach is augmentation: filling the extraction socket with bone graft material to stimulate the growth of new bone. DBM is an attractive option because of its relatively favorable safety profile—it has low immunogenicity, can be stored at room temperature, and has been shown to induce bone formation. This material contains important bioactive proteins, including bone morphogenetic protein (BMP), platelet-derived growth factor (PDGF), and transforming growth factor-beta (TGF-β).
However, the question addressed by Prof. Regina was not solely about bone. She focused on the soft tissue above it: the gingiva, or gums. How quickly do collagen fibers form there? And does DBM influence this process as well?
Thirty-Six Rabbits, Fourteen Days of Observation
To answer these questions, the study used 36 male rabbits aged 2.5 to 3 months, weighing 900–1,100 grams. They were divided into two groups: a treatment group in which the mandibular incisor extraction sockets were augmented with DBM powder measuring 370–710 μm, and a control group that underwent the same procedure without DBM augmentation.
The gingiva was then sutured using non-absorbable thread. The rabbits were sacrificed at different time points on days 1, 3, 5, 7, 10, and 14 after surgery. Gingival tissue measuring 0.5–1 cm² was collected from the extraction area, fixed in 10% paraformaldehyde, and stained using the Van Gieson method—a histological staining technique that makes collagen fibers appear as pink bands under a light microscope.
Collagen density was assessed using a grading system: grade 1 for thin density, grade 2 for moderate density, and grade 3 for thick density. Statistical comparisons between the two groups were performed using the Mann-Whitney test.
The results spoke for themselves. On day 3, the DBM group already showed a mean density of 2.06, while the control group had a mean density of only 1.56. By day 14, the DBM group achieved a perfect score of 3.00 with a standard deviation of zero—meaning that all specimens consistently exhibited the highest collagen density. The control group reached only 2.43.
“DBM allograft has the ability to accelerate gingival reconstruction through stimulation of collagen fiber biosynthesis and re-epithelialization.” — Prof. Dr. drg. Regina TC. Tandelilin, M.Sc., PBO.
The Mechanism Behind Accelerated Healing
This difference was not coincidental. Clinically, on day 3 after extraction, the DBM group had already developed granulation tissue, appearing as pink tissue—a sign of healthy cell proliferation. On the same day, the control group was still dominated by necrotic tissue.
By day 7, the wound in the DBM group had been completely covered by granulation tissue. Fibrin was no longer visible, and the tissue color had blended with the surrounding gingiva. The control group did not reach a similar condition until days 10 to 14.
At the cellular level, the mechanism involves cooperation between the growth factors contained in DBM and recipient cells. PDGF stimulates the chemotaxis of fibroblasts, neutrophils, and macrophages while activating the production of fibronectin and hyaluronic acid. TGF-β, meanwhile, promotes collagen deposition and angiogenesis during the proliferative phase before shifting its function toward regulating excess extracellular matrix (ECM) components during the maturation phase.
One interesting detail is that peak collagen fiber formation in the DBM group occurred between days 5 and 7—a finding consistent with reports by Fonseca and Walker regarding the peak period of collagen fiber formation following wound injury.
From Rabbit Jaws to the Dental Chair
Statistically, the difference in collagen density between the two groups was significant on all observation days except day 1. On the first day, the collagen measured was pre-existing collagen, meaning that it did not yet reflect the response to augmentation.
These findings strengthen the position of DBM as an augmentation material that is relevant not only to bone reconstruction but also actively contributes to the healing of the soft tissue above it. In clinical practice, this could mean faster and more organized post-extraction healing—something highly relevant for patients requiring prosthetic or dental implant rehabilitation following tooth extraction.
The next question, of course, is how far these findings from rabbit jaws can be translated into human clinical practice. The answer is not yet fully available. But the white powder placed inside the wound socket has already demonstrated one thing: healing is not simply a matter of waiting. It can be guided.
Source DOI: https://doi.org/10.22146/theindjdentres.10174
Authors: Anny Anggraini, drg. Achmad Zam Zam Aghasy, M.Kes. Photo: Pexels
Photo: Pexels