Comparison of shearbond strength between metal and indirect resin according to the different conditionings / 대한치과보철학회지

PURPOSE: The purpose of this study is to investigate the differences in bond strength of four different indirect composites to the gold alloy and Ni-Cr alloy according to type of metal surface treatment after water storage. MATERIALS AND METHODS: Type IV gold alloy and Ni-Cr alloy were used for casting alloy while four types of indirect composite resins (Gradia, Tescera Sinfony and in;joy) were used in this study. Metal specimens were produced by casting and total of 240 specimens (60 specimens per one indirect composite group) were prepared. After bonding indirect composite resin and undergoing 24 hours of polymerization, customized jig was attached to the metal specimen and shear bond strength were measured using universal testing machine. Also, differences in shear bond strength before and after water storage for 240 hours were also measured. RESULTS: In the measurement of shear bond strength according to the metal surface treatments, bead group showed high strength followed by loop and flatting group (P<.05). After being stored in water bath for 240 hours, Gradia showed statistically significant high bond strength compared to other indirect composite resins in all groups (P<.05). CONCLUSION: Shearbond strength was found to be different according to type of metal surface treatment and type of metal used after storage in water. Further studies need to be developed for clinical practices as three are still problems of microleakage, stain or wear.

Correction of Depressed Nasal Base and Piriform Aperture Using Polyethylene Implants

Lower midface concavity due to depressed nasal base and pyriform aperture may be aesthetically displeasing. A relative deficiency in lower midface projection may be congenital or acquired, particularly after cleft surgery and trauma. People with normal occlusion associated with lower midface concavity due to depressed nasal base and pyriform aperture can be corrected with an autologous bone graft or artificial implants. The authors performed paranasal augmentation with an alloplastic implants using a porous polyethylene implants(Medpor(R)) on 430 patients who had visited authors' hospital for aesthetic correction of lower midface contour from January 2000 to June 2009. 425 patients were satisfied with the outcome, which gave them a natural contour. Complications such as dislocation, displacement, infection and extrusion were not observed. Only five patients had their implants removed due to displeasing and foreign body sensations. Alloplastic augmentation in the paranasal area is a very easy procedure and can simulate the visual effect as that of maxillary advancement osteotomy. Paranasal augmentation using a porous polyethylene implants(Medpor(R)) in patients having lower midface concavity with normal occlusion can contribute to the enhancement of the lower midface contour.

Near Total Excision in Patients with Angiosarcoma on Scalp

PURPOSE: Angiosarcoma is a rare malignant neoplasm of endothelial type cells that line vessel walls. It tends to occur in aged male and the prognosis of angiosarcoma is very poor because of frequent local recurrence and early metastasis. The treatment regimen is yet to be established from its rare occurrence but the wide excision in early stage is known to be the most effective. The authors report two cases of near totally excised angiosarcoma with more than a safety margin of 5cm. METHODS: The two subjects were aged male patients, one of the two was diagnosed with angiosarcoma from our institution confirmed by the biopsy. The other one went through the wide excision with a safety margin of 2cm and split-thickness skin graft but local recurrence was observed. The two patients underwent near total excision with more than a safety margin of 5cm, leaving only the periosteum. After confirming that the angiosarcoma had not infiltrated the excision margin, reconstruction with split-thickness skin graft was performed. RESULTS: Based on 6 months and 24 months post-surgery assessment, no local recurrence or remote metastasis in the lungs, liver, bones, and lymph nodes at the neck, where remote metastasis is common, was reported by the two subjects who underwent near total excision with a safety margin of 5cm. CONCLUSION: Angiosarcoma has very poor prognosis from its frequent recurrence and metastasis. To enhance the survival rate of angiosarcoma patients, early diagnosis, timely surgical treatment, and radiotherapy after surgery are critical. In addition, authors suggest that it is necessary to further study the efficacy of wide excision using a wider safety margin as much as possible, and to apply this to more cases.

Lipoic acid suppresses compound 48/80-induced anaphylaxis-like reaction / 대한해부학회지

Alpha-lipoic acid (LA), a naturally occurring dithiol compound, is an essential cofactor in metabolic reactions involved in energy utilization. LA improves glycemic control, reduces diabetic polyneuropathies, atherosclerosis, and allergic inflammation. The effects of LA on mast cell-mediated anaphylactic reactions, however, are unknown. LA dose-dependently inhibited systemic and passive cutaneous anaphylaxis-like reactions in mice induced by compound 48/80, a condensation product of N-methyl-p-methoxyphenethylamine and formaldehyde. Pretreatment with LA, prior to induction of the systemic anaphylaxis-like reaction with compound 48/80, reduced plasma histamine levels in a dose-dependent manner. In our in vitro study, LA decreased histamine release from rat peritoneal mast cells (RPMCs) triggered by compound 48/80. Moreover, an increase in calcium uptake activated by compound 48/80 was inhibited by LA. LA also significantly elevated intracellular cyclic adenosine-3',5' monophosphate (cAMP) levels in RPMCs. This inhibition of mediator release from RPMCs may be due to inhibition of calcium uptake and augmentation of intracellular cAMP levels. Based on these results, we suggest that LA may be a potential remedy for allergy-related diseases.

Two-signal blockade with anti-CD45RB and anti-CD154 monoclonal antibodies inhibits graft rejection via CD4-dependent mechanisms in allogeneic skin transplantation

Blockade of signal 1 or 2 for T-cell activation by the use of anti-CD45RB and anti-CD154 monoclonal antibodies (mAb) (two-signal blockade) has been proven effective in preventing or delaying graft rejection. However, the mechanisms of its immunomodulatory effects are clearly unknown and the present studies were performed to determine how the two-signal blockade modulate allogeneic immune responses, especially T-cell mediated cellular immunity, in a murine skin allograft model. We now report on the profound inhibition of alloreactive T cells by two-signal blockade via CD4-dependent mechanisms. C57BL/6 mice of BALB/c skin allograft were treated with anti-CD45RB, anti-CD154, CTLA4-Ig, or their combinations. For depletion of CD4 or CD8 T cells, the recipients received CD4-depleting or CD8-depleting mAb. We confirmed that survival of skin allograft was markedly prolongated in the two-signal blockade-treated group. In depletion study, anti-CD45RB, anti-CD154 and CD4-depleting mAb-treated group showed acute rejection of skin allograft in contrast to CD8-depleting group treated with the two-signal blockade. In the group treated with the two-signal blockade, the proportions of CD4+CD45RB(low)and CD8+CTLA-4 regulatory T cells were increased while effector CD8+ T cells, including IFN-gamma-secreting and CD8+CD62L(low)T cells, were decreased when compared with non-treated group. In contrast, the CD4-depleted group treated with the two-signal blockade resulted in recovery from immunoregulatory effects of two-signal blockade. In addition, results of IL-4 and IL-10 production were also showed CD4-dependence. Therefore, the two-signal blockade is accompanied by CD4-dependent mechanisms in allogeneic skin transplantation.

A Case of Glucagonoma Syndrome Diagnosed as Necrolytic Migratory Erythema / 대한피부과학회지

Necrolytic migratory erythema (NME) is a typical cutaneous manifestation of glucagonoma syndrome. The entire syndrome consists of NME, glucose intolerance, weight loss, anemia, glossitis, diarrhea, and increased glucagon levels. We herein report a patient with glucagonoma syndrome who was diagnosed as having NME. A 48-year-old male presented with a 2-month history of painful erythematous, desquamative, erosive papules and plaques on both lower extremities. Histological examination revealed an intraepidermal cleft, the presence of vacuolated, pale epidermal cells, and necrosis in the upper epidermis. His glucagon level was 2650 pg/ml, with the upper limit of a normal range being 250 pg/ml. The patient was treated with octreotide, and showed an improvement of the skin eruption with normalization of the glucagon level within 4 weeks.

Effect of Hemoperfusion on Treatment for Paraquat Poisoning / 대한내과학회지

Paraquat is a very potent herbicide which causes fatal toxicity when ingested, and there is no specific antidote against it. So it is known that most of the patients who ingested it die of pulmonary fibrosis. We used hemoperfusion(HP) for the treatment against paraquat poisoning from July 1993 till March 1994 and analysed the data using SPSS/PC ver4.0 for chi-square and t-test for mean +/- SD. The results were as follows: 1) A total of 36 paraquat poisoning patients(22 males and 14 females, mean age 48.8 years) visited our hospital, and i8 patients out of 36 received hemoperfusion(total 90 cycles); there were statistically significant differences in ages(41.4 +/- 15.6 year vs 56.2 +/- 15.0 year, p<0.05), but there was no significant difference in the amount of paraquat ingested(59.6 +/- 72.7ml vs 78.6 +/- 83.6ml, p=NS), gastric lavages(13/18 vs 16/18, p=NS), and use of Fuller's earth(8/18 vs 4/18, p=NS) between the patients who received HP and those who did not receive HP. 2) All the patients who did not receive HP died, but 9 patients out of 18 who received HP survived(p<0.005). There was no significant difference in ages(46.8 +/- 9.8 year vs 36.0 +/- 18.8 year, p=NS), amount of paraquat ingested(87.5 +/- 94.2 ml vs 34.8 +/- 36.4 ml, p=NS), gastric lavages(7/9 vs 6/9, p=NS), use of Fuller`s earth(5/9 vs 3/9, p=NS), and interval from the ingestion of paraquat to HP(52.449.9 hr vs 38339.7 hr, p=NS) between patients who died and those who survived, but SCr levels on arrival in expired patients were higher than those in surviving patients(5.0 +/- 3.5mg/dl vs 1.4 +/- 0.6mg/dl, p<0.05). Therefore, this suggests that hemoperfusion is very effective in the treatment of paraquat poisoning, and hemoperfusion is the most important factor in the prognosis of the patients.