Radon-222 levels in New York State homes

Results are presented from a statewide survey that measured annual 222Rn concentrations in over 2000 single-family, owner-occupied homes in New York state. The participants were selected by a random-digit-dialing telephone interview approach developed by Mitofsky-Waksberg which allows inferences to be made from the sample to the statewide population. After completing a telephone questionnaire and agreeing to have their homes monitored, eligible households were mailed alpha-track detectors with instructions to place one detector in the main living area for 2 mo (during the winter heating season), a second in the main living area for 1 y, and a third in the basement (if applicable) for 1 y. The statewide median concentration for the heating-season, living-area readings was 31.6 Bq m-3, with a median of 24.0 Bq m-3 for the annual living-area readings and 51.8 for the annual basement readings. For the state, approximately 95% of the living-area concentrations and 86% of the basement concentrations were below 148 Bq m-3 (4 pCi L-1). In addition, only 1.4% of the readings in the basement were above 740 Bq m-3 (20 pCi L-1).     

Detection and treatment of multiple canals in mandibular premolars

The endodontic treatment of mandibular premolars may not be successful because of failure to recognize and/or treat multiple canals when they are present in these teeth. Factors such as an awareness of data pertaining to the number of canals, knowledge of canal morphology, correct radiographic interpretation, and tactile examination of canal walls are important in detecting the presence of multiple canals. These factors, as well as guidelines for subsequent canal preparation and obturation, are provided.     

Assessment of hepatic viability during cold ischemic preservation

A reliable and easy method for assessing the viability of a cold ischemia-preserved donor liver prior to transplanation into the recepient is needed. Based on an earlier study, we hypothesized that liver free fatty acid (FFA) leakage into the preservation fluid may be a useful, atraumatic indicator of irreversible ischemic injury. The aim of the present study was to determine the time course and magnitude of liver FFA release into the preservation solution and its correlation with the duration of cold ischemic preservation compatible with survival after transplantation. Rat livers (n=48) were flushed and preserved with University of Wisconsin (UW) solution at 4°C for 0, 12, 24, and 48 h. Thereafter, half of the livers were analyzed for preservation fluid FFA (gas-liquid chromatography) and protein. The other half were perfused with Krebs-Henseleit (KH) solution at 37°C for 1 h. Bile secretion and liver enzyme release (SGOT, SGPT, and LDH) were measured in addition to perfusate FFA and protein. Total FFA in the preservation fluid was 24 g/g wet tissue after 12 h; it increased sharply 2.6-fold after 24 h and 3.7-fold after 48 h of preservation. Bile production was normal after 12 h of preservation but fell by 20% and 54% after 24 h and 48 h, respectively. LDH release rose from a value of 20 U/l at 0 time to 120 U/l and 260 U/l after 24 h and 48 h of preservation. These results suggest that liver viability declines sharply between 12 and 24 h of cold ischemic preservation, which corresponds with a sharp decrease in the 1-week survival from 100% to 33% after 12 h and 24 h, respectively, of cold ischemic preservation. We conclude that measuring FFA and LDH in the preservation solution of donor livers may be a useful means of assessing the quality of the cold-preserved liver before insertion into the recipient. We also speculate that a threshold FFA level in the UW preservation fluid indicating irreversible damage may be in the order of 35 g total FFA/g liver. Studies on the clinical applicability of our findings are currently under way.     

Identify and Define All Diagnostic Terms for Periapical/Periradicular Health and Disease States

IntroductionThe purpose of this in-depth investigation was to identify, clarify, and substantiate clinical terminology relative to apical/periapical/periradicular diagnostic states, which is used routinely in the provision of endodontic care. Furthermore, the information gleaned from this investigation was used to link diagnostic categories to symptoms, pathogenesis, treatment, and prognosis wherever possible, along with establishing the basis for the metrics used in this diagnostic process.Materials and MethodsDiagnostic terminologies and their relevance to clinical situations were procured from extensive historic and electronic searches and correlated with contemporary concepts in disease processes, clinical assessments, histologic findings (if appropriate), and standardized definitions that have been promulgated and promoted for use in the last 25 years in educational programs and test constructions and for third-party concerns.ResultsIn general, clinical terminology that is used routinely in the practice of endodontics is not based on the findings of scientific investigations. The diagnostic terms are based on assumptions by correlating certain signs, symptoms, and radiographic findings with what is presumed (not proven) to be the underlying disease process of a given clinical state. There were no studies that specifically tried to assess the accuracy of the metrics used contemporarily for the classification of clinical disease states.ConclusionA succinct diagnostic scheme that could be described thoroughly, agreed on unanimously, coded succinctly for easy electronic input, and ultimately used for follow-up analysis would not only drive treatment modalities more accurately, but would also allow for future outcomes assessment and validation.     

Current Trends in Endodontic Practice: Emergency Treatments and Technological Armamentarium

The current clinical practice of endodontics includes the utilization of a variety of new technological advances and materials. The last comprehensive survey that compared treatment modalities used in endodontic practices was conducted in 1990. The purpose of the current survey was to determine the frequency with which these new endodontic technologies and materials are being used in endodontic practices today. An e-mail questionnaire was sent to the 636 active diplomates of the American Board of Endodontics with current e-mail addresses. Two hundred thirty-two diplomates responded for a response rate of 35%. Calcium hydroxide was found to be the most frequently used intracanal medicament for all cases diagnosed with necrotic pulps. Ibuprofen was the most frequently prescribed medication for pain, and penicillin was the most frequently prescribed antibiotic when an active infection was present. Eighty-two percent of the respondents are still incorporating hand files in some fashion during the cleansing and shaping phase of treatment. Lateral condensation and continuous wave were the most common methods used for obturation. Digital radiography was reported as being used by 72.5% of the respondents, whereas 45.3% reported using the microscope greater than 75% of the patient treatment. Ultrasonics was used by 97.8% of the respondents. It appears from the results that new endodontic technology is currently being used in the endodontic offices of those who responded to the survey.