Effects of hyperbaric oxygen treatment on implant osseointegration in experimental diabetes mellitus

Abstract Objective To evaluate whether hyperbaric oxygen (HBO) treatment has a favorable effect on implant osseointegration in diabetic rabbits. Material and Methods An experimental diabetes model was induced in 32 New Zealand rabbits through IV injection of alloxan. After the state of diabetes had been confirmed, one dental implant was placed in the metaphysical region of each animal's tibia. After the implants' placements, the animals were divided into two groups. Half of the animals underwent HBO treatment, while the other group did not receive HBO treatment and served as the control group. The animals were euthanized at the 4th and 8th weeks. The osseointegration of the implants were compared by histomorphometry and resonance frequency analysis (RFA). Results The Bone Implant Contact (BIC) values were significantly higher in the HBO group than in the control group at the 4th week. There was no difference in the BIC values between the groups at the 8th week. There was no significant difference in the RFA scores between the groups both at the 4th and 8th weeks after the operation. Conclusion Histomorphometry findings suggest that HBO has positive effect on implant osseointegration in the early healing period in diabetic rabbits. However, implant stability is not affected by HBO treatment.

Prostaglandin E1 maintains structural integrity of intestinal mucosa and prevents bacterial translocation during experimental obstructive jaundice.

The absence of bile in the gut lumen induces mucosal injury and promotes bacterial translocation (BT). Prostaglandin E (PGE) has a protective effect on the mucosal layer of the alimentary tract. We hypothesize that PGE1 may prevent BT by its beneficial action on the mucosa of the small bowel. Thirty Wistar albino rats were divided equally into 3 groups; Group 1 (control) underwent sham laparotomy, group 2 obstructive jaundice (OJ) and group 3 (OJ + PGE1) underwent common bile duct (CBD) ligation and transection. Groups 1 and 2 received; 1 mL normal saline and group 3 received 40 mg of the PGE1 analogue misoprostol dissolved in 1 mL normal saline administered by orogastric tube once daily. After 7 days, laparotomy and collection of samples for laboratory analyses were performed, including bacteriological analysis of intestine, mesenteric lymph nodes (MLNs), and blood, and histopathologic examination of intestinal mucosa to determine mucosal thickness and structural damage. Serum bilirubin and alkaline phosphatase levels confirmed OJ in all animals with CBD transection. The mucosal damage score was significantly reduced in jaundiced animals receiving PGE1 compared to jaundiced controls (2.15 +/- 0.74 vs 5.3 +/- 0.59; p < .00001) and mucosal thickness was greater (607 +/- 59.1 microm vs. 393 +/- 40.3 microm; p < .00001). The incidence of BT to MLNs decreased from 90% to 30% (p < .02) when jaundiced rats received PGE1. PGE1 treatment reduced the detection rate of viable enteric bacteria in the blood from 60% to 10% (p < .057). We conclude that administration of PGE1 provides protection against OJ-induced atrophy and damage of intestinal mucosa, and thereby prevents translocation of enteric bacteria to underlying tissues.

Clinical importance of solitary solid nodule of the thyroid in endemic goiter region.

CONTEXT: Endemic area and iodine supplementation may affect the pathogenesis of the nodule which commonly occurs in endemic thyroid enlargement due to iodine deficiency. AIMS: To establish pathological changes in solitary solid and larger nodule of the thyroid in endemic area. SETTING AND DESIGN: Retrospective study in Surgical Department of University Hospital. METHODS AND MATERIAL: We determined 44 surgically treated patients with solitary solid nodule in endemic goiter area in which the population routinely receives iodinated salt. The thyroid nodule was preoperatively evaluated with blood chemistry, ultrasound, nuclear scanning and FNAC. The results of preoperative evaluation, surgical interventions, and histopathological examination were analyzed. STATISTICAL ANALYSIS: Student t test and Fisher's exact test. RESULTS: Twenty (45%;20/44) patients with hot (autonomous) nodule have received the diagnosis of toxic adenoma. Twenty four patients had solitary solid and cold nodule. Total thyroidectomy was performed on two patients with papillary cancer (PTC) diagnosed by FNAC from cold nodules. Forty two patients have been treated with total excision of the lobe including hyper or hypoactive solitary solid nodule. Pathological examination has reported two more cases of PTC and one case of insular cancer arising from cold nodules. Completion thyroidectomy was performed on these 3 patients. CONCLUSIONS: Solitary solid and large nodule is a common indication for thyroid surgery in endemic goiter area. High incidence of hyperthyroidism due to single autonomous nodule, and high rate of malignant change (mainly papillary cancer) in solitary hypoactive nodule arises from this series in endemic thyroid enlargement.