Effects of 17-α ethynyl estradiol on proliferation, differentiation & mineralization of osteoprecursor cells.

Background & objectives: The steroidal estrogen 17α-ethynyl estradiol (EE) is an orally bio-active estrogen used in almost all modern formulations of estrogen-progestin combination preparations of oral contraceptives. Contrasting effects of treatment with combined oral contraceptives on bone mineral density of pre-, peri-, and post-menopausal women have been reported, and it has been suggested that the estrogen dose and the type of progestogen may be the main contributing factors for these contrasting results. The objective of this study was to evaluate the effects of EE on osteoprecursor cells. Methods: The effects of single component of oral contraceptive, EE, were tested to see the relationship between EE and osteoblast proliferation, differentiation and mineralization. Tests used included a cell viability test, alkaline phosphatase (ALP) test, alizarin red-S staining, and a Western blot analysis. The effect on cell viability was determined by MTT assay. Differentiation and mineralization were examined using an ALP test and alizarin red-S staining. Protein expressions related to bone formation, such as estrogen receptor-alpha (ER-α), estrogen receptor-beta (ER-β), bone morphogenetic protein-2 (BMP-2), osteocalcin (OCN), and osteopontin (OPN) were evaluated by using a Western blot analysis. Results: Cultures growing in the absence of EE presented the lowest value for the MTT value. However, there were no significant changes in viability/proliferation when EE was added in the medium. Cultures growing in the absence of EE presented the highest value for the ALP activity, and the additional presence of EE resulted in dose-dependent decrease concerning ALP activity. Interpretation & conclusions: Our finding showed that EE in tested dosage within MC3T3-E1 cells seem to affect the proliferation and differentiation; however, significant differences are achieved in ALP activity in early differentiation phase and further studies are needed to elucidate the mechanisms of EE on bone.

Radiographic follow-up evaluation of sinus augmentation with deproteinized bovine bone and implant installation after loading.

Computed tomography (CT) has been used in diagnosis and implant treatment, and CT can be used to assess the dimensional stability of graft materials after maxillary sinus augmentation. A 50-year-old male patient was treated for the simultaneous placement of implants with sinus augmentation and two post-operative CT scans were performed after the delivery of the prosthesis at 9 months and 15 months after the operation. There were no significant changes in alveolar bone height and the buccal window seemed to show remodeling over time. The continuity of the defect and the cortication were apparent in the 15-month post-operative CT scan. Implants installed simultaneously with sinus augmentation were well in function and the graft material seemed to be stable in maintaining tissue dimensions after the loading of the implants. The presented results need to be validated in further large case series or case-controlled studies.

Restoration of the maxillary anterior tooth using immediate implantation with simultaneous ridge augmentation.

Atrophy is most severe during the first month of post-extraction in the anterior maxilla with the degree of horizontal bone resorption being nearly twice as high as that of vertical bone resorption. The loss of the buccal alveolar plate following tooth extraction may lead to palatal implant positioning of the implants. Thus, immediate or early implant placement in the extraction socket has been suggested, because it would reduce the time period and the number of surgical intervention and yield higher patient satisfaction compared with delayed placed implants. However, placement of an implant immediately after tooth extraction may result in a gap between the occlusal portion of the implant and the surrounding alveolar bone crest. In this case report, an implant-supported restoration which is in harmony with the surrounding hard and soft tissue was created by the immediate implant placement with ridge augmentation in anterior region with high satisfaction from the patient.

Correcting the frenal pull and increasing the width of keratinized mucosa around endosseous implants using denudation procedure.

The frenum exerts a pull upon the tissue and can lead to the continuation of the lesion, and the keratinized tissue provides increased resistance to the periodontium. Various techniques have been used to deepen the vestibule and increase the keratinized mucosa. However, there is no case report on correcting the frenal pull and increasing the keratinized mucosa around dental implant using denudation procedure. This article presents a case of frenal pull that was corrected with denudation procedure with the incision line within the keratinized tissue.