Developing a Dental Scrubs Ceremony to define professional identity and teach professionalism to dental undergraduates; lessons learned.

INTRODUCTION: The UK General Dental Council stipulates that professionalism is a key aspect of the teaching and training of dental students. However, dental educators highlight that teaching dental student's professionalism can be challenging and students often rate this teaching activity negatively. This article documents a teaching initiative at one UK Dental School that aimed to strengthen the professionalism curriculum by introducing a Dental Scrubs Ceremony for second-year students. MATERIALS AND METHOD: The Dental Scrubs Ceremony is inspired by the White Coat Ceremonies that medical students have in universities in North America. It marks the students' first step in their professional and clinical development, with the signing of a pledge of conduct and public presentation of dental scrubs to each student. We report student feedback questionnaire data over a three-year period together with reflections on the merits and limitations of this alternative approach to teaching professionalism. RESULTS: Student evaluation data show that the perceived usefulness and worthwhileness of a Dental Scrubs Ceremony have grown since its inception in 2015. Most students enjoyed the symbolism of the ceremony, receiving their dental scrubs in a formal event. However, there was mixed evaluation for its effectiveness to teach professionalism. CONCLUSION: A Dental Scrubs Ceremony is a useful addition to the formal curriculum of professionalism in a dental school. It provides dental students with an opportunity to be inducted into the dental profession as novice dental students starting out on their professional career.

Experiencing loneliness in parenthood: a scoping review.

AIMS: Chronic loneliness is experienced by around a third of parents, but there is no comprehensive review into how, why and which parents experience loneliness. This scoping review aimed to provide insight into what is already known about parental loneliness and give directions for further applied and methodological research. METHODS: Searches for peer-reviewed articles were undertaken in six databases: PsycINFO, Medline, CINAHL, Embase, Web of Science and Scopus, during May 2019 to February 2020. We searched for English studies which examined loneliness experienced during parenthood, including studies that involved parents with children under 16 years and living at home and excluding studies on pregnancy, childbirth or postbirth hospital care. RESULTS: From 2566 studies retrieved, 133 were included for analysis. Most studies (n = 80) examined the experience of loneliness in specific groups of parents, for example, teenage parents, parents of a disabled child. Other studies examined theoretical issues (n = 6) or health and wellbeing impacts on parents (n = 16) and their offspring (n = 17). There were 14 intervention studies with parents that measured loneliness as an outcome. Insights indicate that parental loneliness may be different to loneliness experienced in other cohorts. There is evidence that parental loneliness has direct and intergenerational impacts on parent and child mental health. Some parents (e.g. with children with chronic illness or disability, immigrant or ethnic minority parents) also appear to be at increased risk of loneliness although evidence is not conclusive. CONCLUSION: This work has identified key gaps with further international, comparative and conceptual research needed.

Osteopontin-targeted probe detects orthotopic breast cancers using optoacoustic imaging.

Improved detection of breast cancer using highly sensitive, tumor-specific imaging would facilitate diagnosis, surveillance and assessment of response to treatment. We conjugated osteopontin peptide to an infrared fluorescent dye to serve as a contrast agent for detection of breast cancer by multispectral optoacoustic tomography (MSOT). Selective binding of the osteopontin-based probe was identified using flow cytometry and near infrared fluorescent imaging in triple negative and HER2 positive breast cancer cell lines in vitro. Osteopontin-750 accumulation was evaluated in vivo using MSOT with secondary confirmation of signal accumulation using near infrared fluorescent imaging. The osteopontin-based probe demonstrated binding to breast cancer cells in vitro. Similarly, after intravenous administration of the osteopontin-750 probe, it accumulated preferentially in the subcutaneous breast tumor in nude mice (557 MSOT a.u. compared to untargeted organs such as kidney (53.7 MSOT a.u.) and liver (32.1 MSOT a.u.). At 2.5 h post-injection, signal intensity within the tumor was 9.7 and 17 times greater in the tumor bed than in the kidney or liver, respectively. Fluorescence imaging ex vivo comparing tumor signal to that of nontarget organs confirmed the results in vivo. MSOT imaging demonstrated selective accumulation of the fluorescent osteopontin targeting probe to tumor sites both in vitro and in vivo, and provided high-resolution images. Further development of this tool is promising for advanced diagnostic imaging, disease surveillance and therapeutic models that limit nontarget toxicity.

An RNA splicing enhancer-like sequence is a component of a splicing inhibitor element from Rous sarcoma virus.

The accumulation in infected cells of large amounts of unspliced viral RNA for use as mRNA and genomic RNA is a hallmark of retrovirus replication. The negative regulator of splicing (NRS) is a long cis-acting RNA element in Rous sarcoma virus that contributes to unspliced RNA accumulation through splicing inhibition. One of two critical sequences located in the NRS 3' region resembles a minor class 5' splice site and is required for U11 small nuclear ribonucleoprotein (snRNP) binding to the NRS. The second is a purine-rich region in the 5' half that interacts with the splicing factor SF2/ASF. In this study we investigated the possibility that this purine-rich region provides an RNA splicing enhancer function required for splicing inhibition. In vitro, the NRS acted as a potent, orientation-dependent enhancer of Drosophila doublesex pre-mRNA splicing, and enhancer activity mapped to the purine-rich domain. Analysis of a number of site-directed and deletion mutants indicated that enhancer activity was diffusely located throughout a 60-nucleotide area but only the activity associated with a short region previously shown to bind SF2/ASF correlated with efficient splicing inhibition. The significance of the enhancer activity to splicing inhibition was demonstrated by using chimeras in which two authentic enhancers (ASLV and FP) were substituted for the native NRS purine region. In each case, splicing inhibition in transfected cells was restored to levels approaching that observed for the NRS. The observation that a nonfunctional version of the FP enhancer (FPD) that does not bind SF2/ASF also fails to block splicing when paired with the NRS 3' region supports the notion that SF2/ASF binding to the NRS is relevant, but other SR proteins may substitute if an appropriate binding site is supplied. Our results are consistent with a role for the purine region in facilitated snRNP binding to the NRS via SF2/ASF.

The effect of a range of disinfectants on the dimensional accuracy and stability of some impression materials.

Disinfection of dental impressions should be considered as a routine procedure in dental surgeries and dental laboratories. Disinfectants can have deleterious effects on some properties of impression materials. The aim of this study was to evaluate the dimensional accuracy and dimensional stability of a model dental stone, reproduced from five commonly used impression materials (Aquasil soft putty/Aquasil Ultra LV; Aquasil Monophase; Aquasil Ultra Heavy; Impregum F and Provil putty/Provil Light CD wash) retained by their adhesives in acrylic resin trays and exposed to three disinfectant solutions (Perform ID; Haz-Tabs and MD 520). Two hundred models were used to investigate the effect of the three disinfectants on the dimensional accuracy of the five impression materials. Five impressions were taken for each impression material for each disinfection treatment group. Measurements were carried out using a High Precision Reflex Microscope. All materials demonstrated a percentage change in dimensions when subjected to no disinfection when compared to the brass master die and all materials demonstrated a percentage change in dimension when subjected to the different disinfection procedures. The results of this study have demonstrated that for all of the materials investigated, the changes in dimensional stability were small in the order of microns. These changes may however be of clinical significance for procedures requiring a high degree of accuracy, for example fixed prosthodontics. The materials respond differently depending on the disinfectant used and it may therefore be appropriate that manufacturers recommend the use of particular disinfectants for their products in order to ensure optimum dimensional accuracy and stability.

Development of Lactococcus lactis encoding fluorescent proteins, GFP, mCherry and iRFP regulated by the nisin-controlled gene expression system.

Fluorescent proteins are useful reporter molecules for a variety of biological systems. We present an alternative strategy for cloning reporter genes that are regulated by the nisin-controlled gene expression (NICE) system. Lactoccocus lactis was genetically engineered to express green fluorescent protein (GFP), mCherry or near-infrared fluorescent protein (iRFP). The reporter gene sequences were optimized to be expressed by L. lactis using inducible promoter pNis within the pNZ8048 vector. Expression of constructions that carry mCherry or GFP was observed by fluorescence microscopy 2 h after induction with nisin. Expression of iRFP was evaluated at 700 nm using an infrared scanner; cultures induced for 6 h showed greater iRFP expression than non-induced cultures or those expressing GFP. We demonstrated that L. lactis can express efficiently GFP, mCherry and iRFP fluorescent proteins using an inducible expression system. These strains will be useful for live cell imaging studies in vitro or for imaging studies in vivo in the case of iRFP.

Detection of microspheres in vivo using multispectral optoacoustic tomography.

We introduce a new approach to detect individual microparticles that contain NIR fluorescent dye by multispectral optoacoustic tomography in the context of the hemoglobin-rich environment within murine liver. We encapsulated a near infrared (NIR) fluorescent dye within polystyrene microspheres, then injected them into the ileocolic vein, which drains to the liver. NIR absorption was determined using multispectral optoacoustic tomography. To quantitate the minimum diameter of microspheres, we used both colorimetric and spatial information to segment the regions in which the microspheres appear. Regional diameter was estimated by doubling the maximum regional distance. We found that the minimum microsphere size threshold for detection by multispectral optoacoustic tomography images is 78.9 µm.

The views of part-time clinical teachers regarding their role in undergraduate education at the University of Bristol Dental School.

INTRODUCTION: UK dental schools are reliant on part-time teachers to deliver the clinical educational component of the course, the majority with a background in general dental practice. Opportunities for promotion are limited, as is the support for obtaining educational qualifications. The aim of this study was to ascertain the views of such teachers at a dental school. MATERIALS AND METHODS: An anonymous online survey was used to obtain both qualitative and quantitative views. RESULTS: The response rate was 80%. The school has n = 50 part-time clinical teachers, who have been teaching for, on average ten years, and for three sessions per week. Eighteen percent of teachers are recognised specialists. Forty-six percent of respondents have a formal teaching qualification, mostly at certificate level, and 55% thought it necessary to acquire a formal teaching qualification. Eighty-eight percent were happy with their role as clinical teachers. CONCLUSION: This study demonstrates that despite the lack of support and prospect of career progression, the majority of part-time clinical teachers at this institution are satisfied with their role.

The contents of dental implant patient information leaflets available within the UK.

PURPOSE: Patient information leaflets are designed to provide easy to follow information summaries and first point of contact information about treatment options. This survey reviewed the content of dental implant patient information leaflets, produced by implant companies and available within the UK in 2011. METHODS: Dental implant companies in the UK were asked to provide samples of their patient information leaflets. The information within the leaflets was then summarised, including the quantity and the types of images used and whether the source of the information was given. Quantitative data was obtained on the amount of information provided, size of images and number of references. RESULTS: A response rate of 71% was obtained and 23 leaflets were studied. Great variation was found between the leaflets, with the word counts ranging from 88 to 5,434, and 44 different topics were identified. The majority of the images used were decorative, and none of the leaflets gave any reference to the sources of their information. Implant treatment was generally described in a positive way, with an emphasis on describing the treatment and the advantages. Much less information was given about the potential disadvantages and risks of complications or failure, including the relevance of periodontal disease or smoking. CONCLUSION: Implant patient information leaflets provided by dental implant companies should not be solely relied upon to provide patients with all the information they need to give informed consent to treatment.

Collective sensing and collective responses in quorum-sensing bacteria.

Bacteria often face fluctuating environments, and in response many species have evolved complex decision-making mechanisms to match their behaviour to the prevailing conditions. Some environmental cues provide direct and reliable information (such as nutrient concentrations) and can be responded to individually. Other environmental parameters are harder to infer and require a collective mechanism of sensing. In addition, some environmental challenges are best faced by a group of cells rather than an individual. In this review, we discuss how bacteria sense and overcome environmental challenges as a group using collective mechanisms of sensing, known as 'quorum sensing' (QS). QS is characterized by the release and detection of small molecules, potentially allowing individuals to infer environmental parameters such as density and mass transfer. While a great deal of the molecular mechanisms of QS have been described, there is still controversy over its functional role. We discuss what QS senses and how, what it controls and why, and how social dilemmas shape its evolution. Finally, there is a growing focus on the use of QS inhibitors as antibacterial chemotherapy. We discuss the claim that such a strategy could overcome the evolution of resistance. By linking existing theoretical approaches to data, we hope this review will spur greater collaboration between experimental and theoretical researchers.

Effects of primary HIV-1 infection on subsets of CD4+ and CD8+ T lymphocytes.

OBJECTIVE: To analyse changes in T-lymphocyte subsets in patients with primary HIV infection and to determine their specificity (and therefore their diagnostic utility) by comparing these changes with those seen in other acute illnesses as well as in HIV-uninfected patients. METHODS: T-lymphocyte subsets were analysed by two- and three-colour flow cytometry, and compared between HIV seroconverters (n = 16), HIV-infected (n = 18) and uninfected (n = 33) controls, patients with infectious mononucleosis (n = 7), and patients suspected clinically of having primary HIV infection but who were later found to be uninfected (referred to as HIV non-converters; n = 17). RESULTS: CD4+ lymphocyte counts were significantly lower in HIV seroconverters (mean, 444 x 10(6)/l) than in the HIV non-converters (793 x 10(6)/l; P = 0.003), HIV-seronegative controls (888 x 10(6)/l; P < 0.0001) and, to a lesser extent, those with mononucleosis (694 x 10(6)/l; P = 0.045). The reduction in CD4+ lymphocytes occurred in both the CD45RA+ (55%) and CD45R0+ (33%) subsets. CD8+ lymphocyte counts were significantly higher in HIV seroconverters (942 x 10(6)/l) than in HIV non-converters (570 x 10(6)/l; P = 0.003) and seronegative controls (467 x 10(6)/l; P < 0.0001), but significantly lower than in the mononucleosis group (3682 x 10(6)/l; P = 0.004). The CD8+ cells in the HIV seroconverters had increased coexpression of CD45R0, human leukocyte antigen (HLA)-DR, CD38 and CD11a/CD18. The mean CD4: CD8 ratio in the HIV seroconverters was 0.49, versus 1.52 in the non-converters (P < 0.0001), 2.08 in the seronegative patients (P < 0.0001) and 0.37 in the mononucleosis patients (P > 0.2). CONCLUSIONS: Primary HIV infection is characterized by a depletion of CD4+ lymphocytes, especially of the CD45RA+ phenotype, and by an increase in CD8+ lymphocytes with an activated phenotype; the latter was also seen in patients with infectious mononucleosis but not in HIV non-converters or HIV-seronegative patients. Patients suspected clinically of having primary HIV infection but with normal T-cell phenotype are less likely to have primary HIV infection. These phenotypic changes, as well as an inverted CD4: CD8 ratio, can readily distinguish patients with primary HIV infection from HIV-uninfected patients except those with infectious mononucleosis. Therefore, T-cell-subset enumeration may be useful in the diagnosis of primary HIV infection.

Pneumocystis carinii pneumonia and cytomegalovirus infection in children with vertically acquired HIV infection.

OBJECTIVES: The outcome of Pneumocystis carinii pneumonia (PCP) in HIV-infected infants is poor, and the role of cytomegalovirus (CMV) co-infection in the course and outcome of PCP is unclear. This study describes the prevalence, clinical characteristics, management and changes in survival over time of vertically HIV-infected infants developing PCP and/or CMV infection. METHODS: Data on children with HIV, born in the UK and Ireland and reported to the National Study of HIV in Pregnancy and Childhood, with PCP and/or CMV were combined with clinical information collected from reporting paediatricians. RESULTS: By April 1998, 340 vertically HIV-infected children had been reported, of whom 93 had PCP and/or CMV, as their first AIDS indicator disease; 85 (91%) were infants. Among infants with PCP, 79% were born to mothers not diagnosed as HIV infected, and there was an independent and statistically significant association with breast-feeding, being black African, and developing CMV disease. Median survival after PCP and/or CMV was significantly better in those born between 1993 and 1998 compared with those born before 1993 (P = 0.009), and worse than after other AIDS diagnoses (P = 0.01). Infants with dual infection were more likely to be ventilated (P = 0.003) and receive corticosteroids (P = 0.002) than those with PCP alone. CONCLUSION: Although survival from PCP and CMV has improved over time, these remain serious and potentially fatal infections among infants in whom maternal HIV status is not recognized in pregnancy. Breast-feeding increases the risk of combined PCP and CMV infection, which is associated with severe disease.

Lymphoid hyperplasia and malignant lymphoma occurring in the ocular adnexa (orbit, conjunctiva, and eyelids): a prospective multiparametric analysis of 108 cases during 1977 to 1987.

We performed a prospective multiparametric correlative clinical, histopathologic, and immunologic analysis of 117 ocular adnexal lymphoid proliferations developing in 108 patients between October 1977 and July 1987. The ocular adnexal lymphoid proliferations were distributed among the 108 patients as follows: orbit 69 (64%), conjunctiva 30 (28%), and eyelids nine (8%). The 117 ocular adnexal lymphoid proliferations were classified as follows: polyclonal lymphoid hyperplasia, 32 (22 orbit, nine conjunctiva, one eyelid) (27%); monoclonal B cell lymphoma, 81 (48 orbit, 25 conjunctiva, eight eyelid) (69%); null cell lymphoma, one (orbit) (1%); and histologically indeterminate, three (one each: orbit, conjunctiva, eyelid) (3%). Patients presenting with ocular adnexal polyclonal lymphoid hyperplasia and monoclonal B cell lymphoma, and patients developing unilateral and bilateral ocular adnexal lymphoid proliferations did not differ significantly with respect to age, sex, presenting complaints, duration of symptoms, or ophthalmic findings. Classifying ocular adnexal lymphoid proliferations into benign and malignant categories by histopathologic criteria and into polyclonal and monoclonal B cell categories by immunophenotypic criteria was not useful in predicting eventual outcome, including the occurrence of extraocular lymphoma. However, the clinicopathologic characteristics did differ according to the anatomic site of involvement and histopathology of the ocular adnexal lymphoid proliferations. Lymphoid infiltrates of the conjunctiva were associated with a lower incidence of extra-ocular lymphoma (20%) than were those of the orbit and eyelid, 35% and 67%, respectively (statistically significant, P less than .03). Ocular adnexal small lymphocytic and intermediate lymphocytic lymphomas were less often associated with extra-ocular lymphoma than were ocular adnexal lymphomas of all other histologic types, 27% and 46%, respectively (P less than .09). However, the single most important and statistically significant prognostic factor in these patients was the extent of disease at the time of presentation with an ocular adnexal lymphoid proliferation (P less than .001). Eighty-six percent of patients presenting with a unilateral or bilateral clinical stage lE ocular adnexal lymphoid proliferation, regardless of the histopathology or the immunophenotype, had a benign indolent clinical course and failed to develop ocular or extra-ocular lymphoma during a median follow-up period of 51 months. The results of this study substantially improve our understanding of extranodal small lymphocytic proliferations in general, and those of the ocular adnexa in particular.

Clinical, morphologic, immunophenotypic, and molecular genetic analysis of bilateral ocular adnexal lymphoid neoplasms in 17 patients.

We investigated the clinical, morphologic, immunologic, and molecular genetic characteristics of the lymphoid tumors occurring in 17 patients with bilateral ocular adnexal lymphoid neoplasia. We found no obvious differences in the age, sex, clinical appearance, or ophthalmic findings between patients with unilateral and those with bilateral ocular adnexal lymphoid neoplasms. Five orbital and two conjunctival lymphoid neoplasms removed from five patients were polyclonal pseudolymphomas, while nine orbital, eight conjunctival, and two eyelid lymphoid neoplasms removed from 12 patients were monoclonal B cell non-Hodgkin's lymphomas. Each pair of simultaneously bilateral lesions occurring in a single individual was morphologically and immunologically identical and exhibited identical immunoglobulin gene DNA rearrangement patterns. None of the five patients with polyclonal pseudolymphomas developed nonocular non-Hodgkin's lymphoma, but one developed a contralateral conjunctival monoclonal B cell non-Hodgkin's lymphoma. Six of the 12 patients with ocular adnexal monoclonal B cell non-Hodgkin's lymphomas developed nonocular non-Hodgkin's lymphoma. The incidence of previous or subsequent systemic nonocular non-Hodgkin's lymphoma in patients with bilateral ocular adnexal lymphoid neoplasms is comparable to that of patients with unilateral disease. In both patient groups, the development of nonocular non-Hodgkin's lymphoma is most commonly associated with ocular adnexal lymphoid neoplasms displaying follicular or diffuse small cleaved cell (poorly differentiated lymphocytic) morphologic characteristics.

Evaluation of deoxyribonucleic acid (DNA) isolated from human bloodstains exposed to ultraviolet light, heat, humidity, and soil contamination.

This study was designed to analyze the effects of common environmental insults on the ability to obtain deoxyribonucleic acid (DNA) restriction fragment-length polymorphisms (RFLP) patterns from laboratory prepared specimens. The environmental conditions studied include the exposure of dried bloodstains to varying amounts of relative humidity (0, 33, 67, and 98%), heat (37 degrees C), and ultraviolet light for periods of up to five days. In addition, the effect of drying over a four-day period in whole blood collected with and without ethylenediaminetetraacetate (EDTA) was examined. The results of the study showed that, under the conditions studied, the integrity of DNA is not altered such that false RFLP patterns are obtained. The only effect observed was that the overall RFLP pattern becomes weaker, but individual RFLP fragments are neither created nor destroyed.

The effects of environment and substrata on deoxyribonucleic acid (DNA): the use of casework samples from New York City.

This study was designed to analyze the effects of the environment and substrata on the quality of deoxyribonucleic acid (DNA) isolated from evidentiary specimens. The quality of DNA isolated from actual casework specimens was determined by measuring its size by agarose gel electrophoresis. The information obtained could be used to predict the suitability of the DNA in the samples for restriction fragment length polymorphism (RFLP) analysis. The evidentiary specimens chosen for DNA were classified according to substrate (scrapings, plastic bags, synthetics, denim, and carpet) and according to a subjective evaluation of the condition of the stain (soiled, damp, or putrefied) and to its size (small or large). The results show that DNA of sufficient quality and high molecular weight (HMW) can be reliably isolated from bloodstains deposited on evidentiary items which have an unknown environmental history and which have dried onto a variety of substrata. Subsequent RFLP analysis of a selected number of these samples verified that the DNA was suitable for this type of analysis.

Characterization of deoxyribonucleic acid (DNA) obtained from teeth subjected to various environmental conditions.

This study was designed to determine the effects of various environmental factors on the deoxyribonucleic acid (DNA) obtained from dental pulp. Extracted teeth were subjected to the following conditions: varying pH (3,7,10); temperature (4 degrees C, 25 degrees C, 37 degrees C, incineration); humidity (20%, 66%, 98%); various types of soil (sand, potting soil, garden soil); seawater; burying the teeth outdoors, and aging (one week to six months). In addition, teeth that had been extracted and held at room temperature for 16 and 19 years were also examined. Following isolation of DNA, the samples were analyzed on yield gels to determine the concentration and integrity of the recovered DNA. Restriction digestion with Pst I was followed by electrophoresis of the generated fragments, Southern transfer to nylon membranes, and hybridization to both human and bacterial probes. It was determined that, aside from soil, the environmental conditions examined did not affect the ability to obtain high-molecular-weight human DNA from dental pulp. Restriction fragment length polymorphic (RFLP) analysis of selected samples was performed. Dental pulp patterns were compared with bloodstain exemplars, revealing matching patterns, although an increase in band-shifting was observed with extended exposure to elevated temperatures.

[Thromboembolism of the right coronary after ventricular tachycardia with inferior wall myocardial infarction and normal coronary arteries and intracavitary thrombus]. / Tromboembolismo da coronária direita pós-taquicardia ventricular em infarto inferior antigo com coronárias normais e trombo intracavitário.

A 47 year-old man, with signals of low cardiac output due to sustained ventricular tachycardia, without history of pain. After clinical control of the arrhythmia, he was underwent to coronary-angiography that showed no obstructive lesion, but a thrombus was present in the distal right coronary artery. There was hypocinesia of the inferior wall of the left ventricle and the presence of a mural thrombus in that region. The patient was kept under clinical treatment and sent back to his cardiologist.

The effect of a range of disinfectants on the dimensional accuracy of some impression materials.

In this study the dimensional accuracy of two model materials; dental stone and plaster of Paris, reproduced from three commonly used impression materials; alginate, polyether and addition-cured silicone, retained by their adhesives in acrylic resin trays and exposed to four disinfectant solutions was evaluated. Ninety casts were used to investigate the effect of the four disinfectants on the dimensional accuracy of alginate, polyether and addition-cured silicone impression material. For each impression material 30 impressions were taken, half were poured in dental stone and half in plaster of Paris. The disinfectants used were Dimenol, Perform-ID, MD-520, and Haz-tabs. Measurements were carried out using a High Precision Reflex Microscope. For the alginate impressions only those disinfected by 5-minute immersion in Haz-tabs solution and in full-strength MD 520 were not adversely affected by the disinfection treatment. All polyether impressions subjected to immersion disinfection exhibited a clinically acceptable expansion. Disinfected addition-cured silicone impressions produced very accurate stone casts. Those disinfected by spraying with fill-strength Dimenol produced casts that were very similar to those left as controls, but those treated by immersion disinfection exhibited negligible and clinically acceptable expansion. The results of the studied demonstrated that the various disinfection treatments had different effects on the impression materials. It is important that an appropriate disinfectant is used for each type of impression material.

Eosinophilic ulcer of the oral mucosa: a report of two cases.

Eosinophilic ulcer of the oral mucosa is a chronic ulcerative lesion which may mimic oral cancer clinically and is occasionally misdiagnosed. This article reports on two patients who presented with such lesions and discusses their diagnosis and subsequent management.