Blood Cells Attachment after Root Conditioning and PRP Application: An in vitro Study

Aim: Root conditioning is aimed at smear layer removal and at dental matrix collagen exposure, which may promote periodontal regeneration. This in vitro study assessed smear layer removal, collagen fiber exposure and the influence of PRP (platelet-rich plasma) application on adhesion of blood cells to the root surface using scanning electron microscopy (SEM). Materials and methods: Scaled root samples (n = 160) were set in five groups and conditioned with: group I - control group (saline solution); group II (EDTA 24%); group III (citric acid 25%); group IV (tetracycline hydrochloride 50 mg/ml); group V (sodium citrate 30%). Eighty samples were assessed using the root surface modification index (RSMI). The other eighty samples were set in two groups. The first group (n = 40) received PRP gel application with a soft brush and the second group (n = 40) received PRP application and then a blood drop. The fibrin clot formation was assessed in the first group and the blood cells adhesion was assessed in the second group using the BEAI (blood elements adhesion index). A previously trained, calibrated, and blind examiner evaluated photomicrographs. Statistical analysis was performed using the Kruskal-Wallis's and Dunn's tests. Results: Group III attained the best results for RSMI and BEAI. Moreover, it was the only group showing fibrin clot formation. Conclusion: Citric acid was the most efficient conditioner for smear layer removal, collagen fiber exposure and blood cell adhesion. Moreover, it was the only group showing fibrin clot formation after PRP application. Clinical significance: This study demonstrated that root conditioning followed by PRP application may favor blood cell adhesion on root surface which may optimize periodontal healing. Keywords: Root conditioning, Blood, Platelet-rich plasma, Smear layer, Edetic acid, Citric acid, Tetracycline, Laboratory research. How to cite this article: Dantas AAR, Fontanari LA, Ishi EP, Leite FRM, Zandim DL, Abi Rached RSG, Sampaio JEC. Blood Cells Attachment after Root Conditioning and PRP Application: An in vitro Study. J Contemp Dent Pract 2012;13(3):332-338. Source of support: The study was financially supported by CAPES-Coordination for the Improvement of Higher Education Personnel (Brasilia, DF, Brazil). Conflict of interest: None declared.     

Influence of concentration, time and method of application of citric acid and sodium citrate in root conditioning

Objective

The aim of this study was to establish the parameters of concentration, time and mode of application of citric acid and sodium citrate in relation to root conditioning.

Material and Methods

A total of 495 samples were obtained and equally distributed among 11 groups (5 for testing different concentrations of citric acid, 5 for testing different concentrations of sodium citrate and 1 control group). After laboratorial processing, the samples were analyzed under scanning electron microscopy. A previously calibrated and blind examiner evaluated micrographs of the samples. Non-parametric statistical analysis was performed to analyze the data obtained.

Results

Brushing 25% citric acid for 3 min, promoted greater exposure of collagen fibers in comparison with the brushing of 1% citric acid for 1 minute and its topical application at 1% for 3 min. Sodium citrate exposed collagen fibers in a few number of samples.

Conclusion

Despite the lack of statistical significance, better results for collagen exposure were obtained with brushing application of 25% citric acid for 3 min than with other application parameter. Sodium citrate produced a few number of samples with collagen exposure, so it is not indicated for root conditioning.     

Negative-pressure wound therapy and laparoscopic omentoplasty for deep sternal wound infections after median sternotomy

Deep sternal wound infection remains one of the most serious complications in patients who undergo median sternotomy for coronary artery bypass surgery.We describe our experience in treating 6 consecutive patients with our treatment protocol that combines aggressive débridement, broad-spectrum antibiotics, negative-pressure wound therapy, omentoplasty with laparoscopically harvested omentum, and the use of bilateral pectoral muscle advancement flaps.The number of débridements needed in order to attain clinically clean wounds and negative cultures varied between 1 and 10, with a median of 5. The length of stay after omentoplasty and bilateral pectoral muscle advancement flap placement varied between 11 and 22 days. One of the 6 patients developed a small wound dehiscence that was treated conservatively. No bleeding related to vacuum-assisted closure therapy was identified. Three patients had pneumonia. Two of the 3 patients had an episode of acute renal failure. The 30-day mortality rate was zero, although 1 patient died in the hospital 43 days after the reconstructive surgery, of multiple-organ failure due to pneumonia that was induced by end-stage pulmonary fibrosis. No patient died between hospital discharge and the most recent follow-up date (4-12 mo). Late local follow-up results, both functional and aesthetic, were good.We conclude that negative-pressure wound therapy-in combination with omentoplasty using laparoscopically harvested omentum and with the use of bilateral pectoral advancement flaps-is a valuable technique in the treatment of deep sternal wound infection because it produces good functional and aesthetic results.     

Non-occlusive mesenteric ischemia: two case reports and a short review of the literature

Introduction: Non-occlusive mesenteric ischemia (NOMI) is an infrequent cause of acute mesenteric ischemia with atypical symptoms and a high mortality.

Patients and methods: We report two cases of NOMI characterized by their difference in etiology, treatment and outcome.

Results: In the first case, the patient developed NOMI after septic shock, she was successfully treated with surgery. The second patient experienced two episodes of cardiac arrest followed by NOMI. He received only supportive care and died shortly after. We present a short review of the literature, discussing epidemiology, pathophysiology, clinical presentations, diagnosis and management of NOMI.

Conclusion: NOMI is a rare disease with a difficult diagnosis. Early recognition and treatment with supportive therapy, vasodilator drugs and possibly surgery can significantly lower mortality.     

Prediction of evolution toward brain death upon admission to ICU in comatose patients with spontaneous intracerebral hemorrhage using simple signs

The aim of the study was to identify the predictors of brain death (BD) upon admission to the intensive care unit (ICU) of comatose patients with spontaneous intracerebral hemorrhage (ICH). Patients admitted in our ICU from 2002 to 2010 for spontaneous ICH and placed under mechanical ventilation were retrospectively analyzed. Of the 72 patients, 49% evolved to BD, 39% died after withdrawal of life support, and 12% were discharged alive. The most discriminating characteristics to predict BD were included in two models; Model 1 contained ≥3 abolished brainstem responses [adjusted odds ratios (OR) = 8.4 (2.4, 29.1)] and the swirl sign on the baseline CT‐scan [adjusted OR = 5.0 (1.6, 15.9)] and Model 2 addressed the abolition of corneal reflexes [unilateral/bilateral: adjusted OR = 4.2 (0.9, 20.1)/8.8 (2.4, 32.3)] and the swirl sign on the baseline CT‐scan [adjusted OR = 6.2 (1.9, 20.0)]. Two scores predicting BD were created (sensitivity: 0.89 and 0.88, specificity: 0.68 and 0.65). Risk of evolution toward BD was classified as low (corneal reflexes present and no swirl sign), high (≥1 corneal reflexes abolished and swirl sign), and intermediate. Simple signs at ICU admission can predict BD in comatose patients with ICH and could increase the potential for organ donation.     

Does preserved kidney volume predict 1 year donor renal function after laparoscopic living donor nephrectomy?

The aim of the present study was to evaluate whether preserved kidney volume predicts donor renal function at 1‐year post‐surgery. Data of patients who underwent laparoscopic living donor nephrectomy between October 2006 and September 2010 were retrospectively reviewed. All patients underwent computed tomography scan with an estimation of kidney volume by using an automated segmentation algorithm. We also calculated kidney volume adjusted for donor body surface area and donor preserved kidney volume ratio (split volume). Estimated glomerular filtration rate was estimated using the Modification of Diet in Renal Disease equation. Predictors of the estimated glomerular filtration rate at 1 year were assessed by multiple linear regression. The 1‐year estimated glomerular filtration rate was available in 140 patients. The median age was 40 years, and median adjusted preserved kidney volume was 160.5 cc/1.73 m² (interquartile range 143.7–177.9). Median estimated glomerular filtration rate was 92.4 (interquartile range 81.9–101.2) and 61.2 mL/min/1.73 m² (interquartile range 53.4–68.7), respectively, at baseline and at 1 year. Preserved kidney volume adjusted to body surface area (P = 0.02) with age (P = 0.002) and preoperative estimated glomerular filtration rate (P < 0.001) were independent predictors of estimated glomerular filtration rate at 1 year. However, split kidney volume was not statistically related to estimated glomerular filtration rate at 1 year (P = 0.47). In order to maximize preservation of donor renal function, the pre‐donation kidney volume adjusted to body surface area might be a useful parameter to consider when deciding on living kidney donation.