Effects of lidocaine with and without epinephrine on plasma epinephrine and lidocaine concentrations and hemodynamic values during third molar surgery.

Lidocaine with epinephrine is currently the most common local anesthetic agent used for impacted third molar surgery. The purpose of the present study was to define the adverse hemodynamic effects and plasma concentrations of lidocaine and epinephrine on 17 healthy patients during the impacted teeth operations. Arterial blood pressure (systolic blood pressure, diastolic blood pressure), heart rate, peripheral oxygen saturation range, and electrocardiography were measured by an automatic noninvasive pressure device and monitor. High-performance liquid chromatography was used to measure the changes of plasma concentrations of epinephrine and lidocaine from blood samples taken 5 different times during the operation. We concluded that lidocaine-epinephrine is effective local anesthetic and had no important adverse events in healthy patients during the third molar surgery.     

Histomorphometric evaluation of the effect of doxycycline on the healing of bone defects in experimental diabetes mellitus: a pilot study.

PURPOSE: Bone healing is impaired in diabetes mellitus, particularly due to increased collagen breakdown. Recently, tetracyclines have been used to treat experimental bone defects because they have anticollagenolytic properties, and positive effects on the healing process have been obtained. The objective of this study was to develop a computer-assisted histomorphometric technique to quantitatively determine the amount of regenerating bone within experimental bone defects in a diabetic rodent model. MATERIALS AND METHODS: This study examined the effects of systemic doxycycline administration on the healing of tibial bone defects in healthy albino rats and in experimentally induced diabetic rats. Twenty-four female albino rats were assigned to 4 groups: diabetic, diabetic plus doxycycline, control, or control plus doxycycline. The standardized bone defects were histomorphometrically examined 10 and 30 days postoperatively. Histomorphometric analysis of the amount of new bone formation was performed using the Zeiss Vision image analysis program KS 400 (Kontron Elektron GmbH, Eching, Germany). RESULTS: At 10 days of healing, the diabetic groups exhibited inferior healing compared with the control groups in terms of the amount of new bone formation within the defects. However, the effect of doxycycline administration to the diabetic and control groups was not statistically different. At 30 days of healing, there were no statistically significant differences between the amount of newly formed bone in any of the groups. CONCLUSIONS: This study found that doxycycline administration did not significantly alter the amount of new bone formation during the healing of bone defects in control and diabetic rats.     

In vitro assessment of the effectiveness of chlorhexidine gel and calcium hydroxide paste with chlorhexidine against Enterococcus faecalis and Candida albicans.

OBJECTIVE: The purpose of this study was to compare the effectiveness of various medicaments, including Ca(OH)2/2% chlorhexidine, 2% chlorhexidine gel, and Ca(OH)2 alone, against Enterococcus faecalis and Candid albicans in vitro. STUDY DESIGN: Eighty extracted single-rooted human maxillary teeth were used. After removing the crown, each root was instrumented up to size 50 by using a conventional technique. The root canal was irrigated with ethylenediamine tetra-acetic acid (EDTA) solution to remove smear layer. Then, roots were infected with E faecalis and C albicans. Subsequently, the roots were divided into 4 treatment groups: group 1 was treated with calcium powder hydroxide in distilled water, group 2 was treated with calcium hydroxide powder in 2% chlorhexidine, group 3 was treated with 2% chlorhexidine gel, and group 4 was treated with 0.9% sterile saline serving as negative control. Microbial samples were taken after 7, 15, and 30 days. After incubation, dentine chips were obtained form each root canal and examined microbiologically. The microbiological samples were plated to count colony-forming units in per milligram of dentin. RESULTS: The results showed that the 2% chlorhexidine gel was significantly more effective than calcium hydroxide with 2% chlorhexidine, calcium hydroxide, and control saline solution (P < .05). CONCLUSION: Under the conditions of this study, 2% chlorhexidine gel is effective in the elimination of E faecalis and C albicans from the root canal system. However, to support this in vitro observation, further in vivo studies are needed.     

Guillain-Barré syndrome during treatment with interferon alpha for hepatitis B.

We describe a patient who developed acute demyelinating polyneuropathy on the sixth week of interferon (IFN)alpha therapy for chronic hepatitis B (HBV) infection. A 23-year-old man with chronic HBV infection had acute onset of demyelinating polyneuropathy shortly after completing a standard 6-week course of therapy with IFNalpha 2a. Clinical findings, electrodiagnostic studies and elevated cerebrospinal fluid protein levels without cells supported the diagnosis of Guillain-Barré syndrome (GBS). Other potential causes of GBS were ruled out. It remains unknown whether IFNalpha or the HBV infection itself was the cause of GBS, but it is evident that IFNalpha could not have prevented the development of GBS in our patient. We suggest that coexistent HBV infection and IFNalpha therapy may play a role in triggering an autoimmune response to peripheral nerve myelin.     

Nonsurgical retreatment of teeth with periapical lesions previously managed by either endodontic or surgical intervention.

OBJECTIVE: The purpose of this study was to evaluate the outcome of nonsurgical retreatment of teeth with periapical lesions, which had been previously managed by either endodontic or surgical intervention, and to identify factors that might influence the prognosis. STUDY DESIGN: Seventy-five endodontically and 11 surgically treated teeth with persisting periapical lesions ranging in size from 2 to 11 mm in diameter were included in this study. The teeth were nonsurgically retreated, using calcium hydroxide as intracanal medicament, and were followed for a period of 2 to 8 years. RESULTS: Clinical and radiographic assessment of retreatment showed that complete healing for all cases was 61.6% with an additional category of incomplete healing of 14%; 24.4% failed. The size of the periapical lesions and previous surgical treatment had marginally negative influences on the prognosis, but the differences were not statistically significant. CONCLUSION: The favourable results of this study demonstrated that nonsurgical root canal retreatment is an alternative to surgical intervention of postendodontic or postsurgical failure.     

Effect of N-acetylcysteine on blood and tissue lipid peroxidation in lipopolysaccharide-induced obstructive jaundice.

In obstructive jaundice, free radical production is increased and antioxidative activity is reduced. N-Acetylcysteine (NAC) has a beneficial effect with anti-inflammatory and antioxidant activity, acting as a free radical scavenger. NAC inhibits inducible nitric oxide synthase, suppresses cytokine expression/release, and inhibits adhesion molecule expression and nuclear factor kappa B. The aim of this study was to investigate the effects of NAC on liver/renal tissue and serum lipid peroxidation in lipopolysaccharide (LPS)-induced obstructive jaundice. We randomized 60 rats into 6 groups: group 1, Sham; group 2, obstructive jaundice (OJ) induced after bile-duct ligation; group 3, OJ + NAC (100 mg kg- 1 subcutaneously); group 4, OJ + LPS (10 mg kg-1); group 5, OJ + NAC + LPS; and group 6, OJ + LPS + NAC. For each group, the biochemical markers of lipid peroxidation and the antioxidant products were measured in serum and liver/renal tissue after sacrifice. Almost all lipid peroxidation products levels were increased and antioxidant products levels were decreased in groups who received LPS (groups 4, 5, and 6), but the effect was less remarkable when NAC was administered before LPS (group 5). The same trend was seen for groups with OJ +/- LPS who did not received NAC or received it after induced toxemia (groups 2, 4, and 6) as compared to groups 1 and 3. Moreover, in the case of OJ + LPS, rats treated with NAC before LPS (group 5) had lower lipid peroxidation products levels and higher antioxidant products levels as compared to those who did not received NAC (group 4). This phenomenon was not reproducible with NAC administered after LPS (group 6). Thus, results of this study showed that NAC prevents the deleterious effects of LPS in obstructive jaundice by reducing lipid peroxidation in serum and liver/renal tissue if administered before LPS. Nonetheless, NAC failed to prevent the lipid peroxidation in the case of established endotoxemia in obstructive jaundice.     

Delay of cranial bone regeneration by CO2 and Nd-YAG laser application: an experimental study related to craniosynostosis

In this study we have investigated the negative influence of CO₂ and Nd-YAG laser irradiation on rapid cranial regeneration and whether it has any use in certain types of craniosynostosis. Twenty-two newborn rats were used in the study. Both CO₂ and Nd-YAG laser irradiation, which was applied to free bony edges after, suturectomies, resulted in a significant decrease in skull regeneration. Histopathological examinations revealed severe degeneration caused by both types of laser energies.     

Microvascular reconstruction of a giant encephalocele defect in a 10-week-old infant.

Microvascular reconstruction of a cranial defect in a 10-week-old infant, which is the youngest case in the literature, is reported. A latissimus dorsi free muscle flap was transferred to cover the defect and a split thickness skin graft was placed over the muscle flap. Despite the successful flap transfer in this case, microvascular reconstruction in an infant has its own risks and infants should be discussed as a separate entity apart from the other pediatric patients.