Wnt Pathway in Bone Repair and Regeneration – What Do We Know So Far

Wnt signaling plays a central regulatory role across a remarkably diverse range of functions during embryonic development, including those involved in the formation of bone and cartilage. Wnt signaling continues to play a critical role in adult osteogenic differentiation of mesenchymal stem cells. Disruptions in this highly-conserved and complex system leads to various pathological conditions, including impaired bone healing, autoimmune diseases and malignant degeneration. For reconstructive surgeons, critically sized skeletal defects represent a major challenge. These are frequently associated with significant morbidity in both the recipient and donor sites. The Wnt pathway is an attractive therapeutic target with the potential to directly modulate stem cells responsible for skeletal tissue regeneration and promote bone growth, suggesting that Wnt factors could be used to promote bone healing after trauma. This review summarizes our current understanding of the essential role of the Wnt pathway in bone regeneration and repair

Optimization of the periodontal attachment before orthodontic treatment

Severe bone loss due to periodontal disease is often associated with migration and dental malpositions and requires orthodontic treatment. After conventional periodontal treatment, which is essential before orthodontic treatment, scaring of the attachment of the periodontal ligament occurs. Recent advances in the field allow us to understand the mechanisms of periodontal healing better, and can result in regeneration of the periodontal ligament. Surgical regeneration procedures in association with orthodontic treatment are complementary. They optimize the support, allowing better long-term results

Optimisation de l’attache parodontale avant traitement orthodontique

Les alvéolyses sévères dues à des maladies parodontales sont fréquemment associées à des migrations et des malpositions dentaires nécessitant un traitement orthodontique. Après un traitement parodontal conventionnel, indispensable avant un déplacement orthodontique, on obtient seulement une attache parodontale de type réparation. Les progrès scientifiques récents nous permettent de mieux connaître les mécanismes de cicatrisation parodontale et d’aboutir à une véritable régénération des tissus parodontaux. La régénération chirurgicale de l’attache parodontale, associée à un traitement orthodontique, est une technique complémentaire d’optimisation du support permettant d’augmenter la pérennité des tissus

Relationships among bone quality, implant osseointegration, and wnt signaling

A variety of clinical classification schemes have been proposed as a means to identify sites in the oral cavity where implant osseointegration is likely to be successful. Most schemes are based on structural characteristics of the bone, for example, the relative proportion of densely compact, homogenous (type I) bone versus more trabeculated, cancellous (type III) bone. None of these schemes, however, consider potential biological characteristics of the bone. Here, we employed multiscale analyses to identify and characterize type I and type III bones in murine jaws. We then combined these analytical tools with in vivo models of osteotomy healing and implant osseointegration to determine if one type of bone healed faster and supported osseointegration better than another. Collectively, these studies revealed a strong positive correlation between bone remodeling rates, mitotic activity, and osteotomy site healing in type III bone and high endogenous Wnt signaling. This positive correlation was strengthened by observations showing that the osteoid matrix that is responsible for implant osseointegration originates from Wnt-responsive cells and their progeny. The potential application of this knowledge to clinical practice is discussed, along with a theory unifying the role that biology and mechanics play in implant osseointegration.National Institutes of Health, 5 R01 DE024000-12 / National Natural Science Foundation of China, 81500829, 81300914 / University of Chile-Conicyt Becas Chile Award CONICYT PAI/INDUSTRIA 7909001