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PubMed1998

The relationship between follicular fluid aspirate volume and oocyte maturity in in-vitro fertilization cycles.

As a consequence of multiple follicular growth during ovarian stimulation for in-vitro fertilization (IVF), follicles of varying sizes often yield oocytes that vary in maturity and morphology of the oocyte-cumulus-corona complex. The objective of this prospective study was to explore the relationship between follicular fluid aspirate volume and the oocyte's developmental potential in an IVF treatment cycle. In total 9933 follicles were studied from 400 patients who underwent 535 consecutive IVF treatment cycles at St James's University Hospital, Leeds, UK, between February 1995 and February 1996. The volume of each individual follicle aspirated was recorded and related to the probability of obtaining an oocyte, its fertilizing capacity, the cleavage rate and the quality of embryos derived. We found no statistically significant difference in oocyte recovery rates between follicles with an aspirate volume < or = 1 ml and follicles with a volume > 1 ml. Although oocytes obtained from follicles with an aspirate volume > or = 1 ml showed a significantly lower fertilization rate, they went on to cleave at the same rate as oocytes obtained from larger follicles and resulted in embryos of comparable quality. Furthermore, there was no statistically significant difference in the implantation, clinical pregnancy or live birth rates per cycle between embryos derived from follicles with an aspirate volume < or = 1 ml and those derived from follicles with an aspirate volume > 1 ml. We conclude that follicular size and the oocyte's developmental potential in the stimulated ovary are not closely related and can be independent. This is in contrast to the Graafian follicle and the pre-ovulatory oocyte in the natural cycle.

Adult↗
PubMed2002

Few instead of many: human follicle collection from follicular aspirates at oocyte retrieval.

BACKGROUND: The aim of this study was to determine if follicular aspirates obtained during oocyte retrieval for IVF were a good source of ovarian follicles for research purposes. METHODS: Follicular aspirates from 86 patients were collected and examined for the presence of follicles, and histological examination of tissue sample found was undertaken. RESULTS: Follicles were only obtained from aspirates of seven out of a total of 86 patients. From these samples a total of 14 follicles was found. The follicles were primordial, primary or secondary, 40-80 microm in diameter. Three of these recovered follicles were cultured and all degenerated within 2 days. In all aspirates some groups of granulosa cells that did not contain follicles or oocytes were found, as was vaginal epithelium that was also identified and verified by histology. CONCLUSIONS: Follicular aspirates are not a useful source of human follicles. Some structures found in the aspirates may be erroneously identified as follicles.

Adult↗
PubMedDate not supplied

Aspiration of oocytes for in-vitro fertilization.

An aspiration system, incorporating a regulated vacuum pump, was used to examine, in vitro, some factors that may affect oocyte collection. In an open aspiration system, as the length of the needle was increased, or the internal diameter decreased, the velocity (and flow rate) of aspirated fluid decreased. There was a difference, however, between experimental flows and those predicted by Hagen-Poiseuille's Law. Upon application of vacuum to a closed aspiration system, employing isolated bovine ovaries, there was an initial rapid increase in the collection tube vacuum to 85% of the selected pump vacuum followed by a more gradual rise to 100%. The vacuum within the needle similarly rose rapidly to approximately half the selected vacuum, while the vacuum at the needle tip was approximately 5% of selected vacuum. The vacuums throughout the system briefly equilibrated as maximum flow/velocity was reached. Flow/velocity slowed dramatically as the follicle collapsed, and stopped as the needle tip was blocked. If vacuum was maintained during the withdrawal of the needle from the follicle, there was a dramatic forward flow of fluid toward the collection tube. The morphological appearance of bovine cumulus after in-vitro aspiration was generally unaltered by vacuums commonly utilized in oocyte collection, providing the cumulus was regular, compact and refractile. The cumulus was less resistant to aspiration if it was damaged or had degenerated. These results suggest that an intact cumulus may offer protection during oocyte collection.

Animals↗
PubMed2001

Breast cancer risk in women with abnormal cytology in nipple aspirates of breast fluid.

BACKGROUND: We previously showed that women with abnormal cytology in breast fluid obtained by nipple aspiration had an increased relative risk (RR) of breast cancer compared with women from whom fluid was not obtained and with women whose fluid had normal cytology. This study extends the follow-up in the original study group (n = 4046) and presents the first follow-up for a second group of women (n = 3627). METHODS: We collected nipple aspirate fluid from women in the San Francisco Bay Area during the period from 1972 through 1991, classified the women according to the most severe epithelial cytology observed in fluid specimens, and determined breast cancer incidence through March 1999. We estimated RRs for breast cancer using Cox regressions, adjusting for age and year of study entry. All statistical tests were two-sided. RESULTS: For women in the first and second study groups, the median years of follow-up were 21 years and 9 years, respectively, and breast cancer incidences were 7.8% (285 cases in the 3633 women for whom breast cancer status could be determined) and 3.5% (115 of 3271), respectively. Compared with women from whom no fluid was obtained, whose incidences of breast cancer were 4.7% (39 of 825) and 3.3% (65 of 1950) for those in group 1 and group 2, respectively, incidences and adjusted RRs were 8.1% (34 of 422), with RR = 1.4 (95% confidence interval [CI] = 0.9 to 2.3), and 0% (0 of 31), respectively, for those with unsatisfactory aspirate specimens and 8.2% (148 of 1816), with RR = 1.6 (95% CI = 1.1 to 2.3), and 3.1% (25 of 811), with RR = 1.2 (95% CI = 0.8 to 2.0), respectively, for those with normal cytology in aspirates. Compared with women from whom no fluid was obtained, incidences and adjusted RRs for women in group 1 with epithelial hyperplasia and atypical hyperplasia in aspirates were 10.8% (52 of 483), with RR = 2.4 (95% CI = 1.6 to 3.7), and 13.8% (12 of 87), with RR = 2.8 (95% CI = 1.5 to 5.5), respectively, while those for women in group 2 were 5.5% (25 of 457) and 0% (0 of 22), respectively, with a combined RR = 2.0 (95% CI = 1.3 to 3.3). CONCLUSION: The results obtained with the newly followed women independently confirmed previous findings that women with abnormal cytology in nipple aspirates of breast fluid have an increased risk of breast cancer.

Adolescent↗
PubMed2006

Role of naso-gastric aspirate in HIV-positive children presenting with respiratory symptoms.

BACKGROUND: Human immunodeficiency virus (HIV) infection predisposes to various opportunistic infections like tuberculosis, Pneumocystis carinii (P. carinii) pneumonia, toxoplasmosis and fungal infections. Naso-gastric aspirate (NGA) is utilized to demonstrate acid-fast-bacilli (AFB); similarly P. carinii was isolated with the help of naso-gastric aspirate in HIV positive children. DESIGN: Prospective study. SETTING: Tertiary care center. OBJECTIVE: To study the role of naso-gastric aspirate in HIV positive patients presenting with respiratory symptoms. METHODS: HIV positive patients less than 5 years age (n = 35) presenting with respiratory symptoms of cough, breathlessness, feeding difficulties and/or tachypnoea were studied. Gastric aspirate was obtained on three consecutive mornings after overnight fasting. 1 volume of dithiotretiol (mucolytic agent) was added to 2 volumes of gastric aspirate. The mixture was incubated for 15 min followed by centrifugation at 1500 r.p.m. for 5 min; the supernatant was decanted. The sediment was re-suspended in phosphate buffer saline with pH of 6.8 and re-centrifuged at 1500 r.p.m. for 5 min. The final sediment was again suspended in phosphate buffer saline followed by addition of 6 drops of 30% bovine serum albumin. Smears were prepared from the sample followed by Zeihl-Neelsen stain for AFB; toluidine blue, Giemsa stain and Gomori's methenamine stain for identification of trophozoite and cyst forms of P. carinii. RESULTS: P. carinii organism was identified in 17 patients (48.57%) with 11 patients having only P. carinii while 6 patients having isolated both P. carinii and AFB. 1 patient had isolated only AFB. The total number of AFB isolated was 7 patients (20.0%). Pulmonary Koch was identified in 17 patients; however AFB was identified in 7 cases (a yield of 41.18%). No complications as a result of the procedure were identified in any of the patients. CONCLUSION: Naso-gastric aspirate is a simple, convenient, relatively non-invasive and economical technique for identification of AFB and/or P. carinii organisms in HIV-positive patients presenting with respiratory symptoms.

Child↗
PubMed1999

Does epinephrine improve the diagnostic accuracy of aspiration during labor epidural analgesia?

UNLABELLED: Aspiration reliably detects almost all IV multiorifice epidural catheters. Although a supplemental epinephrine 15-microg test dose may detect the rare IV catheter that does not yield blood on aspiration, false-positive epinephrine responses may cause some women to unnecessarily undergo repeat epidural catheter insertion. We evaluated 532 consecutive eligible patients requesting neuraxial labor analgesia. Patients were excluded if they had a contraindication to epinephrine or if they received intrathecal sufentanil/bupivacaine. Multiorifice catheters were inserted 4-6 cm into the epidural space as part of an epidural (n = 305) or combined spinal-epidural (n = 270) technique. We used aspiration, a lidocaine/epinephrine test dose, and bolus injection or infusion of dilute bupivacaine/sufentanil solutions to systematically determine IV, intrathecal, or epidural catheter location. Aspiration alone detected 47 of 48 intravascular catheters. There were 10 positive epinephrine responses: 2 were true positives, 7 were falsely positive (subsequent local anesthetic injection/infusion produced bilateral sensory change and analgesia), and 1 catheter was removed without further testing. Aspiration detected almost all intravascular catheters. Although the epinephrine test dose did detect one catheter that proved to be in a blood vessel, 87.5% of positive responses occurred in women without intravascular catheters. IMPLICATIONS: Epidural catheters may enter a blood vessel. Many clinicians use epinephrine to detect these catheters. Because aspiration alone detects almost all IV multiorifice catheters in laboring women, a subsequent epinephrine test dose may be unnecessary.

Adult↗
PubMed2000

Aspiration in transtracheal oxygen insufflation with different insufflation flow rates during cardiopulmonary resuscitation in dogs.

We investigated whether transtracheal insufflation of oxygen with different insufflation flow rates protects against aspiration of gastric contents during cardiopulmonary resuscitation (CPR). Its ventilation and oxygenation effects were also evaluated. Cardiac arrest was induced in anesthetized and paralyzed 18 mongrel dogs. Chest compression using an automatic thumper was performed while the dogs randomly received no mechanical ventilation (Group I, n = 6) or were transtracheally insufflated with 4 L/min oxygen (Group II, n = 6) or 10 L/min oxygen (Group III, n = 6). Blood samples were drawn every 5 min for 20 min for blood gas analysis. the mouths of the dogs were then filled with 70 mL mixed barium, and 10 min after chest compression, chest radiographs were taken to evaluate the incidence of pulmonary aspiration. Results showed that pulmonary aspiration occurred in all dogs of Group I and three of the six dogs in Group II, whereas dogs in Group III were free from pulmonary aspiration. Both transtracheal oxygen insufflation groups maintained oxygen saturation significantly better than Group I, but mild hypercapnia was observed in all groups after 20 min of CPR. We conclude that transtracheal oxygen insufflation, but not chest compression alone, was able to maintain oxygenation for 20 min during CPR in dogs with cardiac arrest. Mild hypercapnia was noted in all groups. Chest compression alone caused pulmonary aspiration, whereas insufflation of 10 L O(2)/min provided better protection against pulmonary aspiration than that of 4 L O(2)/min.

Animals↗
PubMed1983

Fine needle aspiration biopsy of thyroid nodules.

The clinical value of the fine needle aspiration of thyroid nodules was evaluated by comparing preoperative cytology to subsequent pathology in 109 patients undergoing thyroidectomy. Preoperative cytology was reported as insufficient cellular material (31 patients), benign goiter (27 patients), follicular neoplasm (22 patients), thyroiditis (12 patients), suspicious for papillary carcinoma (nine patients), Hurthle cell neoplasm (five patients), medullary carcinoma (one patient), lymphoma (one patient), and metastatic adenocarcinoma (one patient). Operative findings demonstrated that the overall sensitivity of fine needle aspiration in diagnosing thyroid neoplasia (carcinoma or adenoma) was 88% and its specificity was 80%. Operation verified the cytologic diagnosis of medullary carcinoma, lymphoma, metastatic adenocarcinoma, and seven of nine papillary carcinomas. Of the five patients with an aspiration biopsy diagnosis of Hurthle cell neoplasm, three patients had carcinoma and one had an adenoma. Four carcinomas and 12 follicular adenomas were found in patients with a cytologic diagnosis of follicular neoplasm. Thyroiditis was confirmed at operation in all 12 patients with this diagnosis on fine needle aspiration. One carcinoma was found in the 27 patients with benign goiter diagnosed on cytology. Fine needle aspiration is a valuable tool that can lead to earlier diagnosis and treatment of thyroid cancer. However, a negative aspiration does not supplant good clinical judgement in determining the need for thyroidectomy.

Adenocarcinoma↗
PubMed2002

Aspiration in pediatric anesthesia: is there a higher incidence compared with adults?

PURPOSE OF REVIEW: Recent data in both adults and children have suggested that the incidence and severity of the pulmonary aspiration of gastric contents has declined. Previous studies have indicated that aspiration is more common in children than in adults. This review will examine the available data to compare the incidence and severity of aspiration in adults and children. RECENT FINDINGS: There are several studies, some of which have been published recently, that have provided an epidemiologic perspective on the problem of aspiration. SUMMARY: Based on the available data, aspiration appears to be slightly more common in children than in adults. The difference, however, is less than that previously reported. Morbidity associated with aspiration is rare in all age groups. This is especially true for children.

Journal Article↗
PubMed1996

Aspiration of the knee joint before revision arthroplasty.

Sixty-four operative procedures were performed on 55 patients with knee arthroplasties for pain, loosening, instability, or suspicion of infection. Forty-three knees had a preoperative aspiration. In 19 knees, the aspiration showed growth on solid media, and in 18 of these knees the diagnosis of infection was confirmed by the intraoperative cultures. In 1 knee with an infected total knee replacement, the patient was receiving an intravenous antibiotic at the time of arthroscopic irrigation and debridement and the cultures showed no growth. In 23 of 24 knees with a negative preoperative aspiration, the intraoperative cultures showed no growth on solid media. In 1 knee with a preoperative aspiration that had negative results, a single intraoperative culture grew Staphylococcus epidermidis. However, the presenting symptoms, examination, preoperative radiographs, and intraoperative evaluation were consistent with aseptic loosening of a cemented total knee arthroplasty. Thus, the preoperative aspiration of the prosthetic knee joint had a sensitivity of 100%, specificity of 100%, and accuracy of 100%. The Westergren erythrocyte sedimentation rate, peripheral leukocyte count, and presenting symptoms correlated poorly with infection. Radiographs were also not helpful in the diagnosis of infection, with loosening of components, periostitis, focal osteolysis, and radiolucent lines frequently seen in infected and noninfected knees. Preoperative aspiration of the knee is the most helpful study for the diagnosis or exclusion of infection in a prosthetic knee joint.

Adult↗
PubMed2000

Fine needle aspiration biopsy of primary bone tumors.

A review of 66 consecutive fine needle aspiration biopsies of primary bone tumors revealed that 48 (73%) were diagnostic. Twelve (18%) yielded inadequate specimens unsatisfactory for diagnosis, and five (8%) yielded specimens adequate for partial diagnosis. The only error, presumably attributable to sampling error, was an unappreciated dedifferentiated osteosarcoma arising in an otherwise typical giant cell tumor. Fine needle aspiration biopsy obviated the need for open biopsy in 24 patients and simplified surgery in an additional 24 patients by establishing the diagnosis before surgical intervention. A solitary soft tissue recurrence of a giant cell tumor has been the only local recurrence. A review of 26 consecutive patients with osteosarcoma revealed that seven tumors were diagnosed by primary open biopsy. Nineteen patients had fine needle aspiration biopsy, of which 15 were diagnostic and four required supplemental open biopsy. The elapsed time between the initial office visit and the diagnostic confirmation averaged 5 days for patients requiring open biopsy compared with 0 days for patients whose fine needle aspiration biopsy was diagnostic. The total estimated charge for fine needle aspiration biopsy of a distal femoral osteosarcoma was $1060.00 compared with $4312.25 for open biopsy. There have been no local recurrences in patients in either group. Fine needle aspiration biopsy provides an accurate, safe, efficient, well tolerated, and cost-effective method for diagnosing classic primary bone tumors, including osteosarcoma.

Biopsy, Needle↗
PubMed1997

Detection of Pneumocystis carinii in tracheal aspirates of intubated patients using calcofluor-white (Fungi-Fluor) and immunofluorescence antibody (Genetic Systems) stains.

OBJECTIVE: To compare the detection rate of Pneumocystis carinii in endotracheal aspirates with that rate in bronchoalveolar lavage fluid, using calcofluor-white (Fungi-Fluor) and immunofluorescence antibody (Genetic Systems) staining methods. DESIGN: Prospective, consecutive cases. SETTING: Medical intensive care unit at Ben Taub General Hospital. PATIENTS: Thirty-one intubated patients admitted with respiratory failure and suspected P. carinii pneumonia. INTERVENTIONS: An endotracheal aspirate specimen was obtained after maximally advancing a closed-system suction catheter, instilling aliquot portions of saline, and suctioning the lavage fluid. This procedure was followed within 30 mins by fiberoptic bronchoscopy and bronchoalveolar lavage. MEASUREMENTS AND MAIN RESULTS: Endotracheal aspirate and bronchoalveolar lavage specimens from each patient were mixed with Saccomano's fixative, blended, and centrifuged. Using a modified method for P. carinii cysts, the sediment was stained with the test calcofluor-white stain Solution A and the test antibody stain. The test antibody stain on the bronchoalveolar lavage specimens was positive for P. carinii for 13 patients and was used as the standard for comparison. In the endotracheal aspirate specimens, the test antibody stain detected 12 (92%) P. carinii-positive patients while the test calcofluor-white stain detected ten (77%) P. carinii-positive patients. CONCLUSIONS: We described a simple method for obtaining, processing, and staining endotracheal aspirate specimens for P. carinii. Obtaining an endotracheal aspirate specimen did not require specially trained personnel or a specialized and more expensive catheter, and was not associated with any complications.

Benzenesulfonates↗
PubMed1997

Specimen mammography-guided fine-needle aspirates of clinically occult benign and malignant lesions. Analysis of cell number and type.

RATIONALE AND OBJECTIVES: The authors determine the cell counts and percentages of epithelial cells in fine-needle aspirates (FNA) of mammographically detected breast lesions. METHODS: Specimen mammography-guided 20-gauge fine-needle aspirations were performed on 151 consecutive lesions. Cell counts were determined by flow cytometry of 106 consecutive aspirates. Semiquantitative determination of the percentage of epithelial cells was done by cytologic analysis of 151 aspirates. RESULTS: Single FNA cell counts were greater than 1000 for all lesions and greater than 7000 in 57% (31 of 54) of malignant and 35% (18 of 52) of benign lesions, P = 0.02. Fine-needle aspirates of soft tissue abnormalities had more than 7000 cells in 59% (27 of 46) of specimens, compared with 36% (22 of 61) in calcifications, P < 0.05. With the exception of fibroadenomas, the mammographic appearance of benign lesions, lesion size, and patient age had no association with cell counts. Ninety-three percent (76 of 82) of malignant lesion FNA and 80% (55 of 69) of benign lesion FNA had 50% or greater epithelial cells, P < 0.05. CONCLUSIONS: Fine-needle aspiration yields abundant cell counts of predominantly epithelial cells from most types of mammographically detected lesions and should be considered as a source of fresh cell samples for the study of benign and early malignant breast disease.

Adult↗
PubMed1986

Quantitative analysis of blood and fat in suction lipectomy aspirates.

This study of suction lipectomy aspirates from 15 consecutive patients was undertaken to biochemically quantitate the blood-to-fat ratios of the aspirates. A wide variation in the blood-to-fat ratios (8 to 54 percent) was noted, but the authors failed to demonstrate any relationship between the blood-to-fat ratios and the suction lipectomy operative site. Prophylactic measures to allow treatment of patients in a consistently safe manner include carefully screening of patients to exclude those with bleeding disorders or significant illnesses, perioperative oral iron therapy, infiltrating the operation site with a dilute epinephrine solution, hydrating the patients adequately perioperatively, using smaller-diameter cannulas for the aspiration, minimizing aspiration once the aspirate turns grossly bloody, and limiting the aspirate to a volume of less than 1750 ml for any operative procedure.

Adipose Tissue↗
PubMed2002

Eliminating discard volumes in neonatal and pediatric blood sampling from arterial catheters: A comparison of three simple blood-conserving aspiration techniques.

OBJECTIVE: To compare different blood aspiration techniques to eliminate discarding of blood in arterial blood sampling from critically ill neonates and children. DESIGN: Prospective, randomized controlled trial. SETTING: A 19-bed tertiary neonatal and pediatric intensive care unit. PATIENTS: Critically ill neonates and children with existing arterial and central venous access. INTERVENTIONS: Paired blood samples were obtained by using conventional blood discarding techniques and one of the following blood-conserving aspiration techniques: passive extracorporeal arteriovenous backflow, free passive backflow to ambient pressure, and active aspiration backflow to a distance of 10 or 20 cm proximal to the sampling port of the arterial pressure catheter. Repetitive conventional sampling served as a control and as the standard. The order of sampling was randomly allocated. We determined arterial blood gases, electrolytes, blood glucose, and hemoglobin concentration. Measurement and RESULTS: Bland-Altman bias analysis of the variability among the techniques revealed that the passive backflow and the active aspiration backflow technique with a backflow distance of 20 cm yielded identical results to repetitive conventional sampling with a standardized discard volume of 0.6 mL. In contrast, the extracorporal arteriovenous backflow technique carried the risk of overestimating blood glucose levels (mean bias, 0.96 mmol/L.). A backflow distance of 10 cm (active aspiration) proved insufficient to eliminate contamination by the catheters' flushing solution. CONCLUSIONS: At a backflow distance of 20 cm, the passive backflow and the active aspiration backflow techniques produce, with the used monitoring set, reliable and precise results in critically ill newborns and children and eliminate discard volumes.

Journal Article↗
PubMed2005

Investigating the stationarity of paediatric aspiration signals.

An aspiration signal is the time-varying anterior-posterior acceleration measured infero-anterior to the thyroid notch when foreign material enters the airway during inspiration. The hypothesis of weak stationarity is tested on aspiration signals by the reverse arrangements test. Results indicate that aspiration signals cannot be uniformly regarded as weakly stationary. Forty-five percent of the examined signals violated the stationarity hypothesis. For these signals, time-varying variance and spectral density structure are identified as major sources of nonstationarity. Stationarity test results generally corroborate qualitative clinical descriptions of aspiration. However, stationarity analysis indicates that aspiration signals are highly heterogenous, a finding which poses significant challenges to the automatic detection of aspirations by accelerometry.

Acceleration↗
PubMed1993

Foreign body aspiration in children. The diagnostic value of signs, symptoms and pre-operative examination.

One hundred and fifteen patients, between 6 months and 12 years of age, had bronchoscopy on suspicion of foreign body aspiration. The histories of these patients were studied to examine the diagnostic value of signs, symptoms and examinations, and to determine the time that passed between aspiration and removal of the foreign body. The sensitivity of the symptoms choking and coughing was fairly high (81 and 78%), but the specificity was poor. The sensitivity of a chest radiograph was 82%, the specificity 44%. The sensitivity of radiographs on inspiration and expiration was 80%, the specificity 55%. The patients had been referred with the initial diagnosis foreign body aspiration (80), pneumonia (34), or subglottic laryngitis (1). In 85 patients a foreign body was identified and extracted. The other 30 patients had respiratory tract infections. The initial diagnosis of foreign body aspiration was correct in 61 out of 85 patients. In these cases, the period between aspiration and extraction of the foreign body was a mean 6 days, compared with 55 days, if the initial diagnosis was pneumonia or sub-glottic laryngitis. We conclude that the diagnosis of foreign body aspiration is too often missed, and that, apart from bronchoscopy, diagnostic tools are of little value.

Bronchoscopy↗
PubMed2006

An ex vivo evaluation of a new root canal irrigation technique with intracanal aspiration.

AIM: To evaluate the effectiveness of a new root canal irrigation technique with intracanal aspiration in removing the smear layer and to assess irrigant extrusion ex vivo. METHODOLOGY: Thirty-five instrumented canals of extracted human canine teeth that had been resected apically by removing 3 mm of the root tip were divided into one control and four experimental groups of seven teeth each. The roots were fixed in a plastic case and surrounded with normal saline agar coloured with 1% acid red. No irrigation was performed in the control teeth. Each root canal in the experimental groups was irrigated with 9 mL of 14% ethylenediaminetetraacetic acid for 3 min, and then with 6 mL of 6% sodium hypochlorite (NaOCl) for 2 min. In the intracanal aspiration technique, the irrigant was delivered from the tip of an injection needle placed 12 mm from the apical root-end and an aspiration needle that was connected to a Root ZX apex locator placed 2 and 3 mm short of the apical root-end in groups 1 and 2, respectively. In the conventional method, the tip of an injection needle used for delivery of the irrigant and as an active electrode was placed 2 and 3 mm short of the apical root-end in groups 3 and 4, respectively, the tip of the aspiration needle was placed 12 mm from the apical root-end in these groups. The readings of the Root ZX during irrigation were recorded. The cleanliness of the canal was evaluated by scoring smear layer from scanning electron microscopy (SEM) images of the canal. Extrusion of NaOCl was detected by measuring the discoloured area of the agar around the apical root-end. The data obtained were statistically analysed by one-way anova, the Kruskal-Wallis test and Friedman's test. RESULTS: In the SEM study, the canals in groups 1-3 were significantly cleaner than those in the control and group 4 (P < 0.05). The mean Root ZX readings in groups 1-3 were approximately "0.5". The discoloured area in group 3 was significantly larger than the other groups (P < 0.05). CONCLUSIONS: Irrigation using the intracanal aspiration technique allowed more effective removal of the smear layer than that performed by the conventional method in an apically resected canine tooth. The intracanal aspiration technique produced limited extrusion of the irrigant beyond the apical foramen.

Apicoectomy↗