Liposome-Encapsulated Hemoglobin Accelerates Skin Wound Healing in Diabetic dB/dB Mice.

Since liposome-encapsulated hemoglobin with high O2 affinity (h-LEH, P50 O2  = 10 mm Hg) has been reported to accelerate skin wound healing in normal mice, it was tested in dB/dB mice with retarded wound healing, as seen in human diabetics. Two full-thickness dorsal wounds 6 mm in diameter encompassed by silicone stents were created in dB/dB mice. Two days later (day 2), the animals were randomly assigned to receive intravenous h-LEH (2 mL/kg, n = 7) or saline (2 mL/kg, n = 7). The same treatment was repeated 4 days after wounding (day 4), and the size of the skin lesions was analyzed by photography, surface perfusion was detected by Laser-Doppler imager, and plasma cytokines and chemokines were determined on days 0, 2, 4, and 7, when all animals were euthanized for morphological studies. The size of the ulcer compared to the skin defect or silicone stent became significantly reduced on days 4 and 7 in mice treated with h-LEH (47 ± 8% of original size), similar to the level in wild-type mice, compared to saline-treated dB/dB mice (68 ± 18%, P < 0.01). Mice treated with h-LEH had significantly attenuated inflammatory cytokines, increased surface perfusion, and increased Ki67 expression on day 7 in accordance with the ulcer size reduction, while there was no significant difference in chemokines, histological granulation, epithelial thickness, and granulocyte infiltration detected by immunohistochemical staining in the ulcer between the treatment groups. The results suggest that h-LEH (2 mL/kg) early after wounding may accelerate skin wound healing in dB/dB mice to levels equivalent to wild-type mice probably via mechanism(s) involving reduced hypoxia, increased surface perfusion, suppressed inflammation, accelerated in situ cell proliferation and protein synthesis.

Liposome-encapsulated hemoglobin accelerates skin wound healing in mice.

Effects of liposome-encapsulated hemoglobin with high O2 affinity (m-LEH, P50O2 = 17 mm Hg) on skin wound healing in mice were examined. Two full-thickness dorsal wounds 6 mm in diameter encompassed by silicone stents were created in Balb/c mice. Two days later (day 2), the animals randomly received intravenous m-LEH (2 mL/kg, n = 12), homologous blood transfusion (red blood cell [RBC], n = 11), or saline (n = 12). The same treatment was repeated 4 days after wounding (day 4), and the sizes of the skin defects and ulcers were monitored on days 0, 2, 4, and 7, when all animals were euthanized for morphological studies. While the size of the skin defect in relation to the stent ring remained the same in all groups, the size of the ulcer compared with the skin defect (or silicone stent) became significantly reduced on days 4 and 7 in mice treated with m-LEH (46 ± 10% of pretreatment size, P < 0.01) compared with mice treated with RBC transfusion (73 ± 6%) or saline (76 ± 7%). m-LEH treatment significantly accelerated granulation, increased epithelial thickness, suppressed early granulocyte infiltration, and increased Ki67 expression in accordance with the ulcer size reduction, while there was no difference in surface blood flow or CD31 expression among the groups. The results suggest that m-LEH (2 mL/kg) may accelerate skin wound healing in Balb/c mice via mechanism(s) involving reduced inflammation and increased metabolism, but not by improved hemodynamics or endothelial regeneration.

Comparison of mandibular stability after SSRO with surgery-first approach versus conventional ortho-first approach.

METHODS: Postoperative mandibular stability in the surgery-first (SF) approach and ortho-first (OF) approach in orthognathic surgery was retrospectively assessed using the lateral cephalo X-P in 38 patients with skeletal Angle Class III malocclusion who underwent sagittal split ramus osteotomy (SSRO). RESULTS: The postoperative mandibular relapse of the two groups observed from T1 (2 weeks after the surgery) to T2 (for the OF group, a year after surgery; for the SF group, the day orthodontic treatment was completed) was compared. The mean (SD) horizontal relapse at pogonion was 0.86 (0.92) mm in the forward direction in the SF group and 0.90 (1.09) mm in the forward direction in the OF group. No significant difference was found in the amount of horizontal movement between the two groups. On the other hand, the mean (SD) vertical relapse at pogonion was 1.59 (2.91) mm in the downward direction in the SF group and 0.14 (1.30) mm in the upward direction in the OF group, showing a significant difference in the amount of movement between the two groups. The degree of completion of the occlusion at T2 in the SF group was compared with that in the OF group by measuring OB, OJ, L1-occlusal plane angle, and interincisal angle. No significant difference was found between the two groups and the post-treatment occlusion was clinically favourable. CONCLUSION: Although the SF approach has several advantages for patients, the method of operation and fixation should be selected carefully to maintain postoperative mandibular stability.

An Adverse Implication of Radiation Therapy for Implant-Retained Maxillofacial Prostheses.

We report the 19-year postoperative course of a patient whose maxillary defect was reconstructed with maxillofacial implant-retained facial prostheses. The patient received 60 Gy of radiation therapy. Adjunctive hyperbaric oxygen therapy was administered and four 4.0-mm long maxillofacial implants were inserted. Four years and 6 months after insertion surgery, two of the four implants were lost and the others showed bone regression in the surrounding bone. All implants were replaced with Epitec System maxillofacial implants placed in non-irradiated bone. Eleven years and 6 months after replacement, the Epitec System has been maintaining good and firm osseointegration. Appropriate selection of implant sites and no history of radiation therapy are keys to successful implant reconstruction. However, adjunctive hyperbaric oxygen therapy is believed to be effective, osseointegrated implant should be inserted at a point appropriately distant from an irradiated lesion.

Clinical experience of bone anchored hearing aid: a case report.

To improve conventional bone conduction hearing aids, Tjellstrom, Branemark, developed an implant system consisting of a maxillofacial implant that derived from dental implants and a bone conduction hearing aid that was attached directly to the implant. This system has been commercially available as a bone anchored hearing aid (BAHA). More than 10,000 patients have benefited from BAHA in Scandinavia, North America, and many other regions. BAHA first became available in 1977 in Sweden but has not been used in Japan as widely as expected. This paper reports a case of a 8-year use of BAHA for hearing loss caused by microtia and external auditory canal atresia, with a review of literature. The patient has been followed up for 9 years after implant placement. Play audiometry with a loudspeaker showed a hearing loss of 25 dB. The patient says that BAHA is superior to conventional transcutaneous bone conduction hearing aids in easiness of attachment, esthetics, and speech recognition and music recognition. The skin and the bone around the implants remain in favorable condition. She has been free from the use of a headband for a conventional hearing aid.

A new device for fixing the premaxilla with osteotomy in a child with complete bilateral cleft lip and palate in the mixed dentition period--a preliminary case report.

In the treatment of a protruded premaxilla associated with complete bilateral cleft lip and palate, some patients require surgical setback of the premaxilla with osteotomy as functional and aesthetic treatment. No satisfactory surgical approaches have been established for the setback because it is usually difficult to fix the premaxilla after osteotomy in the mixed dentition period. This paper reports the new method for fixing the premaxilla with osteotomy in a child with a severely protruded premaxilla in the mixed dentition period. To fix the segment, we fabricated a device consisting of a palatal bite plate and an anterior tray before surgery. The space between the tray and the premaxilla was filled with soft resin during surgery so that the reposition of the premaxilla could be adjusted. This approach produced a favorable result. Our device has several advantages. It allows the adjustment of repositioning of the premaxilla during surgery. It can change the range of the adjustment according to the intended position of the premaxilla. It allows secure fixation of the segment. It is removable for tooth brushing and observation of bone union. Our device can be applied to many children similar to our patient reported in this paper.

A case of chronic infection 28 years after silicone orbital implant.

Silicone was one of the most common biocompatible materials used for orbital floor reconstruction about twenty to thirty years ago. Recently, surgeons hardly use silicone due to numerous reports of complications such as infection, extrusion and implant displacement. We present a case of chronic infection seen after 28 years of silicone implant used in orbital floor repair. Although it is reported that infection due to silicone implant may decrease after long years of follow up, our case demonstrated the possible case of unexpected infection after more than twenty years with orbital silicone implant.