SAS Statistical Analysis Research Articles

AVALIAÇÃO ULTRASSONOGRÁFICA DOS EFEITOS DA ACUPUNTURA NA INVOLUÇÃO UTERINA EM CADELAS

The aim of this study was to evaluate, by means of ultrasound exam, acupuncture effects on uterine involution during the postpartum period in bitches with electroacupuncture. The phenomenon of eutocic uterine involution was studied in 16 bitches, randomly divided into two groups of eight animals each. Group 1 (G1) was treated with electric stimulation (electroacupuncture) of the needle at the points SP6, L3, Bai Hui, TB1, B23, B26, and group 2 (G2), the control group, received treatment in Sham points (placebo points), also with electrical stimuli. The monitoring of the phenomenon of uterine involution was performed by ultrasonography on days 0 (partum), 1, 3, 7 and 14 postpartum. We used SAS statistical analysis method, in order to compare the groups. The results of ultrasound examinations (mean and standard deviations in cm) for the period of observation were as follows: G1: 0.30 ± 0.01 (P), 2.08 ± 0.21 (LU), 4.13 ± 0.23 (DU) and G2: 0.31 ± 0.01 (P) 1.82 ± 0.09 (LU), 3.92 ± 0.11 (DU). We concluded that electroacupuncture affected uterine tone (lasting and uniform at the end of treatment). Electroacupuncture produces a positive tone in the uterus, aiding at the prevention of puerperal diseases.KEYWORDS: bitch; electroacupuncture; uterine involution; postpartum; ultrasound.

Nutrition Assessment of N-P-K in Mint (Mentha spicata L.) Cultivated in Soilless System

Aims: The objective of this study was to determine the nutrient removal of N, P and K in the biomass production of mint plants at the harvest time. Study Design: A randomized complete block experimental design with five replicates and a time series arrangement was used. Data were adjusted by polynomial regression models with SAS statistical analysis system. Place and Duration of Study: The experiment was set up in a shade house (35% shade) located in Xalisco, Nayarit in western Mexico during the spring-summer of 2011, using a commercial variety of mint. Methodology: The harvest days were 20, 40, 60, 80, 100 and 120 days after transplant (DAT), dates on which shoots 15 cm in length, the required size in the international market, were obtained. Steiner solution was used at five concentration levels: 25, 50, 75, 100 and 125%. The growth medium was volcanic slag with 0.3-1 cm granulometry. Plant height, fresh and dry plant biomass and stem diameter were assessed at each sampling date. Nutrient removal of nitrogen, phosphorus and potassium was determined in the different samples in order to understand the absorption dynamics of these elements under commercial management. Results: The results showed that the 100% nutrient solution (NS) concentration increased plant height (PH) by 34% during the first five cuts. Stem diameter (SD) had no significant differences among treatments. Above-ground fresh biomass (AGFB) and above-ground dry biomass (AGDB) were greater in the 100% NS treatment. Nitrogen, P and K (mgkg-1) removal was dependent on the ionic concentration of the nutrient solution. Conclusion: The concentration of the nutrient solution modified fresh and dry biomass production in mint plants. The concentration of the nutrient solution must be increased for optimal yield.

The comparison of the effect of UK and rt-PA intravenous thrombolytic therapy for acute myocardial infarction

Objective To compare the clinical effect of UK and rt-PA intravenous thrombolytic therapy for acute myocardial infarction.Methods By SAS statistical analysis system,72 patients with acute myocardial infarction were randomly divided into rt-PA group and UK group,each group had 36 cases.The coronary artery recanalization rate,bleeding events,adverse cardiovascular events,mortality,and cardiac troponin T(cTnT) level were recorded.Results In rt-PA group,0.5h,1 h,2h after the start of thrombolytic therapy,the coronary artery recanalization rate was significantly higher than that in the control group,the difference was statistically significant (x2 =7.32,6.12,5.81,all P ＜ 0.05).In rt-PA group,3 cases had bleeding events,2 cases died,and in UK group,5 cases had bleeding events,3 cases died,,there was no statistically significant difference between the two groups (x2 =1.22,P ＞ 0.05).In rt-PA group,there were 6 cases with adverse cardiovascular events,14 cases in the control group,the difference was statistically significant (x2 =4.56,P＜0.05).2 cases died in rt-PA group,3 cases died in UK group,the mortality between the two groups had no statistically significant difference (P ＞ 0.05).The cTnT level in the hospital 6h,12h was significantly higher than admission in two groups (t =6.67,6.30,4.11,4.22,4.40,all P ＜ 0.05).In rt-PA group,cTnT level in the hospital 6h,12h was significantly lower than that in UK group (t =5.92,6.61,all P ＜0.05).Conclusion Compared with UK,rt-PA in the treatment of acute myocardial infarction can increase recanalization rate,decrease adverse events and myocardial injury,it is worthy of clinical application. Key words: Myocardial infarction; Urinary plasminogen activator; Recombinases ; Thrombolytic therapy

Avaliação agronômica de genótipos de bananeira no Vale do Rio Siriji, Pernambuco

A produtividade dos bananais da Zona da Mata de Pernambuco e considerada extremamente reduzida e a bananicultura praticada, a excecao de alguns poucos grandes produtores, ainda e de baixo nivel tecnologico, utilizando-se de cultivares inadequadas com baixo rendimento, porte alto e suscetibilidade as principais pragas e doencas, alem do uso de um rudimentar manejo fitotecnico e fitossanitario. As cultivares mais plantadas sao ‘Pacovan’ e ‘Prata’, ambas correspondendo a cerca de 90% dos plantios existentes, sendo os 10% restantes compostos por outras variedades como ‘Comprida’, ‘Maca’, ‘Ana’ (Nanica) e ‘Ana do Alto’ (Nanicao). A necessidade de incrementar o sistema de producao com alternativas tecnologicas, fez com que a Embrapa Tabuleiros Costeiros instalasse no Vale do Rio Siriji, PE, um experimento em area de agricultor, com o objetivo de avaliar sete genotipos superiores de bananeira durante o primeiro e o segundo ciclo de producao nessa regiao, mediante o uso de descritores fenotipicos que refletem a interacao genotipoambiente, relevantes para a identificacao e selecao de individuos com caracteristicas superiores, que possam ser recomendados com fins de aumentar a produtividade media da bananicultura regional. Os genotipos avaliados foram os tipos Pacovan/Prata: PV 42-53, PV 79-34, Japira, Preciosa e ST 12-31, e os tipos Maca: YB 42-03 e YB 42-07, fornecidas e multiplicadas pela Embrapa Mandioca e Fruticultura Tropical, em Cruz das Almas, BA. O experimento foi conduzido em delineamento de blocos ao acaso com sete tratamentos, quatro repeticoes de blocos e parcelas com 12 plantas uteis. O espacamento utilizado foi o de 3,00 m x 3,00 m, e as covas tiveram a dimensao de 0,40 m x 0,40 m x 0,40 m. As plantas, conduzidas sob irrigacao por microaspersao, foram submetidas aos tratos culturais recomendados para a bananeira. Foram considerados os caracteres: numero de dias entre a primeira a segunda colheita; do plantio a emissao da inflorescencia; da emissao da inflorescencia a colheita; e do plantio a colheita; altura da planta; circunferencia do pseudocaule; n° de folhas vivas no florescimento e colheita; peso do cacho; n° de pencas/cacho e de frutos/penca; peso, comprimento e diâmetro do fruto; e espessura da casca. As analises de variância foram realizadas com a utilizacao do programa SASStatistical Analysis System, e as medias foram agrupadas pelo teste Scott-Knott a 5% de probabilidade. No primeiro ciclo, houve diferenca para os caracteres comprimento do fruto e espessura da casca, com a formacao de dois grupos, entre os demais nao houve diferenca, embora os hibridos de Pacovan tenham apresentado excelentes caracteristicas de producao, entre eles a cultivar Japira se destacou em relacao ao peso do cacho (19,52 kg), numero de penca (7,4) e o peso do fruto (104,95 g). No entanto, no segundo ciclo, houve diferenca significativa para a maioria dos caracteres avaliados, sendo que para o peso do cacho, o hibrido ST 12-31 se destacou com o maior valor (19,3 kg), seguida da Preciosa (17,4 kg) e da PV 42-53 (16,7 kg). Outras caracteristicas importantes como peso e comprimento do fruto apontam os hibridos de Pacovan entre os que apresentaram os melhores valores: de 137,92 a 152,83 g, para peso do fruto e de 145,01 a 163,04 cm, para comprimento do fruto. Os hibridos ‘Preciosa’, ‘Japira’ e ‘PV 42-53’ apresentam os melhores desempenhos em relacao aos demais genotipos e potencial para exploracao no Vale do Rio Siriji, em virtude das vantagens observadas nas caracteristicas vegetativas e de producao, alem da boa aceitacao entre os agricultores locais, quanto as caracteristicas agronomicas.

168 INFLUENCE OF SEVERAL INSULIN PLASMA CONCENTRATIONS ON PROGESTERONE PRODUCTION AND HISTOLOGY OF CORPORA LUTEA IN SUPEROVULATED EWES

Nutritional status is essential for the determination of mammalian reproductive performance, and insulin is one of the main indicators for such condition. This hormone is able to interfere, directly or indirectly, with CL function, leading to alterations in steroidogenic capacity and cell development and, consequently, early embryonic development. The aim of this work was to identify CL histological alterations caused by different insulin plasma concentrations in superovulated ewes, as well as their interference in CL progesterone production. Santa Inês ewes (n = 24, 4 years old) were divided into 3 treatments: control (T1, n = 9); hypoinsulinemic (T2, n = 6), and hyperinsulinemic (T3, n = 9). In order to become hypoinsulinemic, ewes were treated with a single dose of alloxan monohydrate (50 mg kg-1 i.v; Sigma-Aldich, St. Louis, MO, USA) 48 h before the beginning of the superovulation protocol, whereas the hyperinsulinemic group was treated with administrations of 20 IU of NPH human insulin at every 12 h (Biolin-N; BIOBRAS, Montes Claros, Brazil). All animals were fed corn silage and minerals ad libitum. Animals had their estrus synchronized with vaginal pessaries containing medroxyprogesterone acetate (60 mg) and were superovulated with porcine FSH (250 IU, PLUSET®, Calier, Spain) and eCG (250 IU, Novormon®, Schering-Plough, Kenilworth, NJ, USA), in a 13-day protocol. After removal of vaginal pessaries, blood samples used for quantification of progesterone and plasmatic insulin by radioimmunoassay were collected daily at 0700 h until the day before embryo recovery. Hysterectomy was performed in all groups after embryo recovery (T1: n = 3, T2: n = 6, and T3: n = 4), and ovaries were placed in buffered formalin saline. CL histological sections were evaluated by hematoxylin/eosin staining. Results were assessed by SAS statistical analysis software, using the MIXED procedure (SAS Institute Inc., Cary, NC, USA). Mean values were compared by Tukey’s test. The mean CL number was lower in T2 (5.0 ± 2.7; P < 0.05) compared with T1 (10.2 ± 5.1) and T3 (11.3 ± 3.0) animals. No histological differences were observed between treatments T1 and T3. However, CL within the T2 group had a higher number of cells with picnotic nuclei and strongly contracted eosinophilic cytoplasm. Such alterations are suggestive of cellular apoptosis. The T2 group also differed for P4 production (P < 0.01) from the second (T2: 2.23 ± 0.71 ηg mL-1; T1: 5.42 ± 4.01 ηg mL-1; T3: 6.44 ± 2.76 ηg mL-1) to the sixth day post-estrus (T2: 7.58 ± 7.00; T1: 24.79 ± 8.40; T3: 32.07 ± 0.85 ηg mL-1). The mean insulin plasma concentration differed between treatments (P < 0.01); higher concentrations were obtained in the T3 group (20.05 ± 7.50 μIU mL-1), whereas the T2 group had lower concentrations (10.18 ± 3.57 μIU mL-1) compared to controls (T1: 14.52 ± 3.80 μIU mL-1). In conclusion, low plasma concentration of insulin may restrict the response to superovulatory treatment and cause CL histological changes, suggesting a reduction in cell activity due to premature cellular senescence.

Effect of Biofilm Dryness on the Transfer of Listeria monocytogenes Biofilms Grown on Stainless Steel to Bologna and Hard Salami

Listeria monocytogenes continues to be a major cause of class I food recalls in the United States. Very little is known about its transfer and cross-contamination in processing scenarios. The objective of this study was to evaluate the effect of hydration level on L. monocytogenes biofilms grown on stainless steel and its effect on the biofilm transfer to foods. Biofilms were grown on stainless steel in diluted tryptic soy broth 1:20 for 48 h at 32°C. After this, biofilms were equilibrated over saturated salt solutions at 20°C for 24 h (94, 75, 58, and 33% relative humidity; % RH) prior to transferring. Transfer experiments were conducted from inoculated stainless steel to bologna and hard salami at a constant pressure (45 kPa) and time (30 s) with a universal testing machine. The experiment was designed with a factorial design 4 × 2 (biofilms equilibrated at 4% RH and two foods) and duplicated every day, and the whole experiment was repeated nine times. The results were analyzed with an analysis of variance by SAS Statistical Analysis Software. Our results showed that more bacteria were transferred to bologna (mean efficiency of transfer [EOT] = 3.0) than to hard salami (mean EOT = 0.35, P < 0.01). As biofilms became drier, the transfer of Listeria from stainless steel to both foods increased (P < 0.05). The EOT increased from 2 to 3.8 and from 0.2 to 0.51 upon transfer when drying the biofilm for bologna and hard salami, respectively. This study may be an indication that as biofilms were dried, the cell-cell and cell-surface interactions became weaker, and bacterial transfer increased. This phenomenon was enhanced in foods containing higher water activity levels. We hypothesize that this increased in transfer was due to the presence of capillary forces in the food.

Radiofrequency Correction of GERD (Stretta) Results in Significant, Long Term 4-Year Improvement in Symptoms, Quality of Life and Medication Use in the Medically Refractory GERD Patient

Radiofrequency Correction of GERD (Stretta) Results in Significant, Long Term 4-Year Improvement in Symptoms, Quality of Life and Medication Use in the Medically Refractory GERD Patient Mark D. Noar, Sahar Lotfi A single center, intent to treat, trial of long-term efficacy and safety of the Stretta procedure for treatment of medically refractory GERD despite multi-dose PPI medical therapy was conducted. Methods: Beginning August 2000, 109 subjects with documented GERD and/or regurgitation and inadequate symptom control despite minimum bid PPI had an outpatient Stretta procedure via conscious sedation by one doctor (MN), and were followed for 4C years. Patients with normal anatomy, or failed Nissen, large (O3 cm) hiatal hernia, erosive esophagitis, and Barrett’s metaplasia were included. Exclusion criteria were: ASAOIII, collagen vascular disease, stricture, or achalasia. Baseline on/off meds and follow-up 6, 12, 24, 36, 48 months GERD-HRQL scores (0-50), heartburn (0-5), satisfaction (0-5) and medication-use were collected. All statistics performed with SAS or JUMP Statistical Analysis Software. Results: 109 subjects entered study. 13/109 failed to respond. 96 responders followed thru year 4. GERD-HRQL, heartburn, satisfaction, and medication use significantly improved at all follow-up intervals 6, 12, 24, 36, 48 months, (p ! 0.001) and were superior to those achieved on baseline drug therapy. At year 4, patients were divided into 4 medication use categories: 1) No meds, 2) PRN antacids/OTC PPI, 3) Daily PPI QD, 4) PPI BID. 75% of patients showed significant improvement into categories 1 or 2 (p ! 0.05). In all parameters, no significant difference between patient scores at baseline on or off meds was noted. A comparative analysis between patients with (33) and without (76) erosive esophagitis showed significant improvement in both groups with no difference between groups, with durability of results maintained to 4 years without statistical difference between the two groups (p O.7). Anatomic differences did not alter success or response to treatment. No acute adverse events or pathological histological changes occurred. Conclusions: 1) The Stretta procedure has a significant positive and sustained effect on medication use, HRQL, satisfaction and GERD symptoms, with durability of response demonstrated at 4 years, 2) The observed improvement was superior to that achieved with escalated baseline antisecretory therapy, and 3) There was no difference in response in patients with variant anatomy such as Nissen fundoplication, hiatal hernia, erosive esophagitis or Barrett’s esophagus.

WHO systematic review of maternal morbidity and mortality: the prevalence of severe acute maternal morbidity (near miss).

AimTo determine the prevalence of severe acute maternal morbidity (SAMM) worldwide (near miss).MethodSystematic review of all available data. The methodology followed a pre-defined protocol, an extensive search strategy of 10 electronic databases as well as other sources. Articles were evaluated according to specified inclusion criteria. Data were extracted using data extraction instrument which collects additional information on the quality of reporting including definitions and identification of cases. Data were entered into a specially constructed database and tabulated using SAS statistical management and analysis software.ResultsA total of 30 studies are included in the systematic review. Designs are mainly cross-sectional and 24 were conducted in hospital settings, mostly teaching hospitals. Fourteen studies report on a defined SAMM condition while the remainder use a response to an event such as admission to intensive care unit as a proxy for SAMM. Criteria for identification of cases vary widely across studies. Prevalences vary between 0.80% – 8.23% in studies that use disease-specific criteria while the range is 0.38% – 1.09% in the group that use organ-system based criteria and included unselected group of women. Rates are within the range of 0.01% and 2.99% in studies using management-based criteria. It is not possible to pool data together to provide summary estimates or comparisons between different settings due to variations in case-identification criteria. Nevertheless, there seems to be an inverse trend in prevalence with development status of a country.ConclusionThere is a clear need to set uniform criteria to classify patients as SAMM. This standardisation could be made for similar settings separately. An organ-system dysfunction/failure approach is the most epidemiologically sound as it is least open to bias, and thus could permit developing summary estimates.

231EXPRESSION PATTERN OF CERTAIN DEVELOPMENTALLY IMPORTANT GENES IN BOVINE NUCLEAR TRANSFER EMBRYOS PRODUCED USING CELL LINES OF DIFFERENT EFFICIENCY

Developmental abnormalities associated with the cloning process suggest that reprogramming of donor nuclei into an embryonic state may not be fully completed in most of the cloned animals. One of the areas of interest in this respect is the analysis of gene expression patterns in nuclear transfer embryos to dissect the processes that failed and to develop means to overcome the limitations imposed by these factors. In this study, we investigated the expression patterns of histone deacetylase-1,-2,-3 (HDAC-1,-2,-3), DNA methyltransferase-3A (DNMT3A) and octamer binding protein-4 gene (POU5F1) in donor cells with different cloning efficiencies (low: no-pregnancy, medium: pregnancy but no live birth and high: live birth) and nuclear transfer embryos derived from these cell lines using a real time reverse transcription-polymerase chain reaction (RT-PCR) assay with SYBR green chemistry. Employing standard protocols, we produced nuclear transfer embryos from three different cell lines categorized as having varying efficiencies in supporting development to term. Embryos were collected at morula, blastocyst and hatched blastocyst stages and total RNA was extracted from pools of 4–5 embryos using Absolutely RNA nanoprep kit (Stratagene, La Jolla, CA, USA). Relative level of expression at these stages was analyzed using ΔΔCT method with HH2A as the reference gene and in vitro-fertilized embryos as the control samples. Statistical analysis was performed on ranked expression data employing SAS statistical analysis software procedure ANOVA. Same set of genes were also analyzed on donor cells using standard curve method. All genes investigated were affected by nuclear transfer and followed somewhat altered expression patterns. In general, expression of HDAC genes was elevated especially at the compact morula stage but became comparable to control embryos at the hatched blastocyst stage. DNMT3A expression in NT embryos was lower than in IVF embryos at all stages. POU5F1 transcript levels were also reduced in nuclear transfer embryos at the compact morula and blastocyst stages. The difference, however, disappeared at the hatched blastocyst stage. There was a cell line effect on the expression patterns of all genes investigated. Cell lines efficient in producing offspring tended to resemble control embryos in gene expression patterns compared to inefficient cell lines. These results agree with several studies reporting altered gene expression patterns for certain genes in cloned embryos. Our data also suggest that cell line differences in developmental competency observed in cloning experiments might be related to physiological differences in transcriptional regulation and nuclear remodeling, DNA methylation, and lineage differentiation in embryos cloned from these cell lines.

Miscarriage rate is not increased in polycystic ovarian syndrome patients compared with other infertility diagnoses

Objective: To evaluate the risk of clinical pregnancy loss in patients with a diagnosis of polycystic ovary syndrome (PCOS) compared with other infertility diagnoses. Design: Retrospective weight- and age-matched cohort study in a tertiary REI teaching center. Materials and Methods: 486 consecutive infertility patients having a positive pregnancy test were evaluated. Patients diagnosed with PCOS were oligo-anovulatory, without ovulatory progesterone, and had evidence of either hyperandrogenism or hyperandrogenemia. All had polycystic appearing ovaries on endovaginal sonography. Comparison patients were ovulatory and had one or more diagnoses of infertility including unexplained infertility, mild male factor, pelvic factor, hypogonadotropic hypgonadism or mildly diminished ovarian reserve. All patients had at least one patent tube. Patients with unexplained infertility or total motile inseminates between 5 and 20 million/ml underwent washed intrauterine insemination following gradient separation. The most frequent intervention in both groups was gonadotropin therapy. Pregnancy was diagnosed by a positive serum βhCG 14 days following ovulation. Pregnancy outcome was determined by reviewing medical records. To control for the effects of weight and age, each PCOS miscarriage patient was matched with the next three consecutive PCOS delivered patients of the same age (within 1 year), and the matching process repeated for weight (within 5 pounds). SAS statistical analysis software was used. Chi-square evaluated classification versus outcome status and independent and matched t-tests were used for parametric data. Significance for p <0.05 was tested using two-tailed distributions. Results: Pregnancy results were available for all patients. The overall rate of early miscarriage in our non-PCOS infertility pregnancy group was 26.0%. In the 139 PCOS patient cohort, the miscarriage rate was 20.0% (p=n.s.). In our PCOS cohort, the mean age of the delivered group was 32.8 years vs. 35.2 years in the miscarriage group (p = 0.01). The mean weight in the PCOS delivered group did not differ from the PCOS miscarriage group (162.7 vs. 166.4 lbs, p=n.s.). However, among non-PCOS patients, a 6.4 lb. difference between miscarriage patients (151.7 lbs) and delivered patients (145.3 lbs) was significant (p < 0.05). When each PCOS patient with early miscarriage was age-matched with the next three consecutive PCOS delivered patients the difference in weight was 0.2 lbs (p = n.s.). In a similar weight-matched analysis of PCOS patients, the difference in age between early miscarriage and delivered patients was 1.2 years (p = n.s.). Examining separately those 15% of PCOS patients who underwent long protocol downregulation with subsequent luteal phase support for IVF, these similarities persisted. Serum total Testosterone showed no association with pregnancy outcome. Conclusion: Despite the perception that PCOS patients are at higher risk for miscarriage, these data suggest that treated PCOS patients when matched for age and weight with patients having other infertility diagnoses do not experience increased clinical pregnancy loss.

Macronutrient intake during the pre-onset, acute, and post weight-recovery period in women with anorexia nervosa: The national heart, lung, and blood institute growth and health study

Macronutrient intake during the pre-onset, acute, and post weight-recovery period in women with anorexia nervosa: The national heart, lung, and blood institute growth and health study

A Waist Circumference/growth Chart Projection for Children

A total of 792 subjects aged 1–251 months (males=384, females=408) were studied cross-sectionally. Anthropometric measurements were obtained according to standardized procedures. Data were divided into two group, 0–36 months and 2-21 years, and analyzed using the SAS statistical analysis package. Pearson correlation values were determined for measurements, age, height and weight. Viable growth charts were developed for males and females 2–21 years for waist circumference. High correlations were found between waist circumference and weight (r=*0.91 and r=*0.88, respectively) for both males and females age 2–21 years. Moderately high correlations were found between waist circumference and age for males (r=*0.82) and females (r−*0.81) age 2–21 years. Waist circumference was moderately correlated to percent body fat for the 0–36 month population (males r=0.77 and females r=0.71), but not for the 2–21 year population. BMI was moderately correlated to waist circumference for the 2–21 year population (males r=0.75 and females r−0.77) but not for the 0–36 month population. The strong correlations between waist circumference and weight for 2–21 years of age support the validity of using waist circumference measurements to determine weight when traditional measurement techniques are not possible or are inconvenient. The waist circumference growth charts developed appear to be viable tools for assessing changes in weight in children.

Success and failure in periradicular surgeryA longitudinal retrospective analysis

The objective of the present study was to compare the success rates of 2 different periapical surgical techniques, the traditional technique with rotary instruments and the ultrasonic technique, which uses ultrasonic retrotips. A longitudinal retrospective study was carried out on 302 apices (181 teeth) that had undergone periapical surgery. Surgical outcome was evaluated by 2 independent operators using standardized periapical radiographs. Each radiographic finding was classified into 1 of 4 groups: complete healing, incomplete healing, uncertain healing, and unsatisfactory outcome (failure). An SAS statistical analysis system was used for data management and analysis. Prognostic factors were determined by means of the Fisher exact test. Complete healing after 4.6 years (the average follow-up period) was observed in 68% of the teeth treated through the use of the standard technique and 85% of those treated through the use of the ultrasonic technique. The success rate increased as the follow-up period lengthened (68.4% at 2 years vs 80% at 6 years). The success rate was higher in maxillary (77.9%) than in mandibular (66.1%) teeth. A comparison between the retrofilling materials was not feasible because all teeth in the standard technique group were retrofilled with amalgam and all teeth in the ultrasonic group were retrofilled with Super-EBA. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;87:493-8)