The use of bur and laser for root caries treatment: a comparative study.

This research analyzed the influence of bur and erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser caries removal on cavity characteristics and marginal seal of composite resin restorations. One hundred and forty human dental root samples were used. After in vitro root caries induction using Streptococcus mutans, the carious lesions were removed either by a conventional technique using burs (G1=control) or by using an Er,Cr:YSGG laser (λ=2.78 µm, 20 Hz, pulse duration is approximately equal to 140 µs, noncontact mode using a 600-µm tip) with the following power outputs: G2: 1.0 W; G3: 1.25 W; G4: 1.5 W; G5: 1.75 W; G6: 2.0 W; G7: 2.25 W; G8: 2.5 W; G9: 2.75 W; G10: 3.0 W; G11: 3.25 W; G12: 3.5 W; G13: 3.75 W; and G14: 4.0 W. Samples in the 14 groups (n=10) were conditioned with Clearfil SE Bond and restored with a flowable composite. They were then thermocycled (1000 cycles) and immersed into a 2% methylene blue solution for microleakage analysis. The data were statistically compared (analysis of variance or Spearman correlation tests; p≤0.05). The lased groups showed significantly greater microleakage indexes, cavity depths, and presence of residual caries than did those of the control group. There was a strong positive correlation between residual caries and microleakage. The results indicate that Er,Cr:YSGG laser irradiation is not a good alternative to the use of burs for root caries removal since it may cause a significant loss of marginal sealing in composite resin restorations.

Obese and nonobese recipients had similar need for ventilatory support after liver transplantation.

BACKGROUND: Obesity is a risk factor for patients undergoing major surgery. In liver transplantation, the morbidity and mortality in these patients may be higher owing to concomitant diseases that may prolong hospital stay. Moreover, the restrictive respiratory pattern in these patients, associated with pulmonary complications related to liver disease can impact the postoperative recovery. We sought to analyze the impact of high body mass index (BMI) on hospital and intensive care unit (ICU) stay, necessity and length of use either invasive and noninvasive ventilatory support in the early postoperative period after liver transplantation. PATIENTS AND METHODS: Between January 2007 and March 2009, we performed 85 liver transplantations in adult patients. BMI was calculated on the day of the transplantation. Data from 136 recipients undergoing OLT were reviewed by age, gender, etiology of liver disease, Model for End-Stage Liver Disease score, Child-Pugh class, cold and warm ischemic times, ICU stay, duration of invasive mechanical, and use of noninvasive ventilation (NIV). We divided the patients into 3 groups: Group 1, (normal weight BMI 18.5-24.99), versus group 2 overweight--BMI 25-29.99; versus group 3, obese--BMI ≥30. RESULTS: Groups 1, 2, and 3 had similar lengths of stay in the ICU, necessity of NIV as well as 6 month, 1- and 2-year survivals (P > .05). CONCLUSION: High BMI patients showed similar results to normal or overweight patients. Obesity should not be contraindication to liver transplantation.

Analysis of Model for End-Stage Liver Disease (MELD) score in a liver transplantation waiting list.

BACKGROUND: The Model for End-Stage Liver Disease (MELD) was introduced in 1999 to quantify the 3-month prognosis of cirrhotic patients after a transjugular intrahepatic portosystemic shunt (TIPS). Because of the imbalance between organ donors and patients on the waiting list, the MELD was adopted by the United States in 2002 to allocate liver grafts for transplantation. Preliminary results have indicated a reduction in waiting list deaths and an increase in transplantation rates for candidates. Seeking to find a new model to predict death on the waiting list and after liver transplantation, retrospective studies have examined MELD scores in waiting list patients. The aim of this study was to analyze the MELD scores of patients on the liver waiting list for comparisons between transplanted patients. PATIENTS AND METHODS: A retrospective study was performed analyzing 131 registrations of 127 orthotopic liver transplant (OLT) patients (4 underwent retransplantation) grafted between November 2000 and January 2006, excluding 24 patients: 2 had urgent retransplantations due to hepatic artery thrombosis and 22 had incomplete data. These patients were divided into 3 groups: group I (transplanted patients)-53 patients underwent 55 OLT; group II-29 patients who died on the waiting list; group III-patients on the waiting list including 23 patients still waiting as of the date of the study. RESULTS: The main indication for OLT was hepatitis C virus cirrhosis (50.50%), followed by alcoholic liver cirrhosis (23.30%), cryptogenic cirrhosis (12.60%), autoimmune hepatitis (5.80%), hepatitis B virus cirrhosis (4.85%), and primary biliary cirrhosis (2.91%). Group I: MELD score 15.62 (range, 6-39) on admission to the list, and 18.87 (range, 7-39) at transplantation. The mean waiting time for OLT was 478.39 days (range, 2-1270 days). The 38 patients who survived underwent 39 OLT (1 retransplantation). The MELD score at entrance to the list was 14.62 (range, 7-30) and at transplantation, 17.70 (range, 7-39). The mean time between admission to the list and transplantation was 505.37 days (range, 6-1270 days). The 15 patients who died had received 16 OLT (1 retransplantation). Their MELD scores were 17.80 (range, 6-39) and 21.81 (range, 9-39) at admission to the list and at transplantation, respectively, with a mean time on the waiting list of 417.93 days (range, 2-872 days). Group II: 29 patients died before OLT, at a mean age of 52.60 years (range, 22-67 years). Their MELD score was 19.24 (range, 7-45), and the interval between admission to the waiting list and death was 249.55 days (range, 3-1247 days). Group III: 23 patients still active on the OLT waiting list at the time of study displayed a mean MELD score of 13.65 (range, 6-28) and 354.30 days (range, 2-905 days) waiting until the moment. In conclusion, MELD score at the time of admission to the waiting list was higher among those patients who died either awaiting a liver graft (19.24) or after OLT (17.80) compared with those who survived after OLT (14.60) or are still awaiting OLT (13.65).

Correlation between graft arterial anatomy and biliary complications after liver transplantation.

Knowledge of the arterial vascular anatomy of the liver is important for orthotopic liver transplantation (OLT) because the lack of an adequate arterial blood supply results in biliary and parenchymal complications or graft loss. A number of reports have shown a relationship between aberrations of graft arteries and an increased incidence of early or late complications. Recent studies suggest no differences unless multiple anastomoses are required. The aim of this study was to report the incidence of aberrant hepatic arterial anatomy and its impact on vascular and biliary complications. We retrospectively reviewed data of 90 OLT performed on 82 patients, including 4 who underwent retransplantation from March 2003 to March 2006. The means recipient age was 52.47 years and 49 were men. The main caval vein reconstruction technique was piggyback (n = 55; 61.2%). The biliary reconstruction was performed by an end-to-end choledocho-choledocho anastomosis in 83 cases (92.3%) with choledocho-jejunal anastomosis (Roux-in-Y) in 7 cases (7.7%). Aberrant arterial anatomy was noted in 20 liver grafts (22.2%), namely, accessory right hepatic artery (n = 6; 6.6%), accessory left (n = 10; 11%), both accessory right and left (n = 3; 3.3%), and hepatic common artery from mesenteric artery (n = 1; 1.1%). Among the transplantations of grafts with aberrant arterial anatomy, 2 cases (10%) developed hepatic artery thrombosis (HAT) and 4 (20%) biliary complications. The rate of HAT and biliary complications among grafts with normal arterial anatomy was 3 and 8 cases (4.2% and 11.42%), respectively. Despite a greater number of complications among OLT with aberrant arterial anatomy, the Fisher test showed no significant relationship between HAT or biliary complications and aberrant arterial anatomy.