17beta-estradiol promotes cementoblast proliferation and cementum formation in experimental periodontitis

NÚÑEZ J; SANZ BLASCO S; VIGNOLETTI F; MUÑOZ F; CAFFESSE RG; SANZ M; VILLALOBOS C; NUÑEZ L

JOURNAL OF PERIODONTOLOGY

AMER ACAD PERIODONTOLOGY

Año: 2010 vol. 81 p. 1064 - 1074

0022-3492

Background: Periodontitis is a chronic inflammatory condition that leads to the destruction of the tooth-supporting tissues. Its treatment includes the arrest of the inflammatory process and, in some circumstances, the restoration of the lost anatomy and function, including the formation of new cementum, periodontal ligament (PDL), and bone. With this goal, we investigated the effects of low concentrations of 17β-estradiol on human cementoblast proliferation and its possible regenerative potential in vivo. Methods: Human cementum-derived cells obtained from a healthy human premolar were isolated and characterized by immunocytochemistry. Cell proliferation assays were performed to test the effects of 100 nM 17β-estradiol and enamel matrix derivative (EMD). Three-wall intrabony periodontal defects were created in beagle dogs. After 1 month of plaque accumulation, 0.225 mg 17β-estradiol impregnated in a collagen sponge was applied to randomly selected defects (test group), whereas a collagen sponge impregnated in a culture medium was applied to the control group. After 3 months, specimens were obtained, and tissue regeneration was assessed by histometric analysis. Results: Cells spreading out from human tooth-layer explants were able to form cell colonies, produce a mineral matrix, and express osteocalcin, indicating they were cementoblast-like cells. In contrast, PDL fibroblasts did not express osteocalcin. 17β-estradiol, but not EMD, increased the rate of human cementoblast cell proliferation in vitro by 2.5-fold. Histometric results from the treated periodontal defects revealed that 17β-estradiol promoted the formation of 2.94 mm of new cementum, (45% of the defects) compared to 1.54 mm of new cementum in the control group (28% of the defects). Furthermore, the test group showed an inhibition of epithelial downgrowth and a gain of new connective tissue attachment. Conclusion: 17β-estradiol promoted human cementoblast cell proliferation in vitro and periodontal regeneration in an experimental periodontitis model.