Ipek Isik

Reconstruction of orbital floor fracture using solvent-preserved bone graft

The orbital floor is one of the most frequently damaged parts of the maxillofacial skeleton during facial trauma. Unfavorable aesthetic and functional outcomes are frequent when it is treated inadequately. The treatment consists of spanning the floor defect with a material that can provide structural support and restore the orbital volume. This material should also be biocompatible with the surrounding tissues and easily reshaped to fit the orbital floor. Although various autografts or synthetic materials have been used, there is still no consensus on the ideal reconstruction method of orbital floor defects. This study evaluated the applicability of solvent-preserved cadaveric cranial bone graft and its preliminary results in the reconstruction of the orbital floor fractures. Twenty-five orbital floor fractures of 21 patients who underwent surgical repair with cadaveric bone graft during a 2-year period were included in this study. Pure blowout fractures were determined in nine patients, whereas 12 patients had other accompanying maxillofacial fractures. Of the 21 patients, 14 had clinically evident diplopia (66.7 percent), 12 of them had enophthalmos (57.1 percent), and two of them had gaze restriction preoperatively. Reconstruction of the floor of the orbit was performed following either the subciliary or the transconjunctival approach. A cranial allograft was placed over the defect after sufficient exposure. The mean follow-up period was 9 months. Postoperative diplopia, enophthalmos, eye motility, cosmetic appearance, and complications were documented. None of the patients had any evidence of diplopia, limited eye movement, inflammatory reactions in soft tissues, infection, or graft extrusion in the postoperative period. Providing sufficient orbital volume, no graft resorption was detected in computed tomography scan controls. None of the implants required removal for any reason. Enophthalmos was seen in one patient, and temporary scleral show lasting up to 3 to 6 weeks was detected in another three patients. Satisfactory cosmetic results were obtained in all patients. This study showed that solvent-preserved bone, which is a nonsynthetic, human-originated, processed bioimplant, can be safely used in orbital floor repair and can be considered as another reliable treatment alternative.

The fate of hydroxyapatite cement used for cranial contouring: histological evaluation of a case.

Craniofacial contouring is a commonly performed procedure applied for traumatic and postsurgical cranial vault or facial skeleton irregularities. Hydroxyapatite cement is an alloplastic material composed of tetracalcium phospate and dicalcium phospate anhydrous that transforms into a paste-like substance when these two compounds placed in an aqueous environment. This mixture, which is a nonceramic microporous calcium phosphate combination, is another alternative for refining the craniofacial contour. There are not enough data regarding bone formation within this material after its use in human beings, however. A case requiring secondary craniofacial contouring after a motor vehicle accident is presented. Hydroxyapatite cement was used for reconstruction, and a second look was carried out for further correction during which secondary contouring of the cement was made and a sample of the previously implanted material was histologically evaluated. It was observed in this case that hydroxyapatite cement is incorporated within the surrounding bony structures and permits secondary contouring procedures. New bone and vessel formation was also detected within the implanted material, but this was limited and thus was not convincing for significant osteoconversion as seen in animal studies.

Expression of steroid receptors in intact rat uterus, mammary gland, and liver treated with selective estrogen receptor modulators and conjugated equine estrogens.

The aim of the present study was to determine the effects of conjugated equine estrogens (CEE) and selective estrogen receptor modulators (SERM) (tamoxifen [TAM] and raloxifene [RAL]) on the expression of steroid receptors—estrogen receptor (ER) and progesterone receptor (PR)—in intact rat uterus, mammary gland, and liver. A total of 24 female rats weighing 250 to 300 g were randomized into 4 groups. Groups 1, 2, 3, and 4 were respectively given conjugated equine estrogen, tamoxifen, raloxifene, and vehicle for a 28-day period. ER and PR expression was detected in tissues of the uterus, mammary gland, and liver. Uterine wet weight and serum estradiol levels were established for all groups. No statistical difference was observed between groups in the ER expression of mammary gland and liver and in the PR expression of uterus, mammary gland, and liver, but differences were noted in serum estradiol levels and uterine ER expression. Serum estradiol levels were lower in the TAM-treated group; differences between the TAM-treated group and the other groups were statistically important (P > .05). Uterine ER expression was greater in the CEE-treated group; differences between the CEE-treated group and theTAM and RAL-treated groups were statistically important (P > .05). CEE or SERM versus vehicle treatment in controls did not seem to result in statistically important differences in ER and PR expression in intact rat uterus, mammary gland, and liver. Only ER expression in the uterus was found to be greater in the CEE-treated group than in SERM-treated groups.