Complications of augmentation procedures for dental implants in private practice, Victoria, Australia.

PURPOSE: This study audited complications associated with augmentation for dental implants, retrospectively over a 5-year period in a variety of private dental practices in Victoria (Australia). METHODS: Complications were categorized as surgical or biological and compared to a group not requiring augmentation. Implant factors underwent univariate and multivariate analysis. RESULTS: The study assessed 8486 implants with 26.9% undergoing augmentation. Augmentation had no effect on implant survival, however, a significant increase in complications for those implants requiring augmentation was found (P = <0.001). The hard tissue augmented group had significantly more cases of insufficient bone/dehiscences at implant placement (P < 0.001), and post-placement bone loss (P = 0.0014). These implants were grafted simultaneously (P < 0.05) with particulate autogenous bone and/or Bio-Oss (P < 0.05) with resorbable xenograft membrane (P < 0.001). There was significantly more bone loss in open sinus lifted cases than implants placed in native bone (1.90% v 0.30%; P = 0.009). CONCLUSIONS: The study demonstrated no increase in graft complications that could be related to any specific augmentation technique, suggesting that routine grafting procedures used in private practice were safe and appropriate. Previously augmented sites were found to be more likely to require further augmentation at implant placement.

Deliberating performance targets workshop: Potential paths for emerging PM2.5 and O3 air sensor progress.

The United States Environmental Protection Agency held an international two-day workshop in June 2018 to deliberate possible performance targets for non-regulatory fine particulate matter (PM2.5) and ozone (O3) air sensors. The need for a workshop arose from the lack of any market-wide manufacturer requirement for Ozone documented sensor performance evaluations, the lack of any independent third party or government-based sensor performance certification program, and uncertainty among all users as to the general usability of air sensor data. A multi-sector subject matter expert panel was assembled to facilitate an open discussion on these issues with multiple stakeholders. This summary provides an overview of the workshop purpose, key findings from the deliberations, and considerations for future actions specific to sensors. Important findings concerning PM2.5 and O3 sensors included the lack of consistent performance indicators and statistical metrics as well as highly variable data quality requirements depending on the intended use. While the workshop did not attempt to yield consensus on any topic, a key message was that a number of possible future actions would be beneficial to all stakeholders regarding sensor technologies. These included documentation of best practices, sharing quality assurance results along with sensor data, and the development of a common performance target lexicon, performance targets, and test protocols.

Incorporation of the microencapsulated antimicrobial agent phytoncide into denture base resin.

BACKGROUND: This study aimed to fabricate a denture base resin (DBR) containing phytoncide microcapsules (PTMCs) and determine the mechanical properties of the resin and antifungal activity. METHODS: Fifty-four heat-cured rectangular DBR specimens (64 × 10 × 3.3 ± 0.2 mm) containing nine concentrations of PTMC between 0 and 5% (wt/wt) were fabricated and subjected to a three-point bending test. A phytoncide release bioassay was developed using DBR containing 0% and 2.5% PTMCs (wt/wt) in a 24 well-plate assay with incubation of Porphyromonas gingivalis at 37 °C for 74 h. The antifungal activity of PTMCs against Candida albicans, in a pH 5.5 acidic environment was determined in a plate assay. RESULTS: Flexural strength decreased with increasing PTMC concentration from 97.58 ± 4.79 MPa for the DBR alone to 53.66 ± 2.46 MPa for DBR containing 5.0% PTMC. No release of phytoncide from the PTMCs in the DBR was detected at pH 7.4. The PTMCs had a minimal inhibitory concentration of 2.6% (wt/vol) against C. albicans at pH 5.5. CONCLUSIONS: PTMCs can be added to DBR 2.5% (wt/wt) without adversely affecting flexural strength. PTMCs released the antimicrobial agent at pH 5.5 at concentrations sufficient to inhibit the growth of the C. albicans.

Ultrafast demagnetization at high temperatures.

Time-resolved pump-probe measurements were made at variable heat accumulation in Co/Pd superlattices. Heat accumulation increases the baseline temperature and decreases the equilibrium magnetization. Transient ultrafast demagnetization first develops with higher fluence in parallel with strong equilibrium thermal spin fluctuations. The ultrafast demagnetization is then gradually removed as the equilibrium temperature approaches the Curie temperature. The transient magnetization time-dependence is well fit with the spin-flip scattering model.

Demagnetizing fields in all-optical switching.

A model of demagnetizing fields and micromagnetic simulations are applied to examine the evolution of a demagnetized cylinder. In addition to three expected final magnetic structures, a fourth switched state is obtained over a range of magnetic energy densities. The switched state is absent when demagnetizing fields are neglected. The connection to all-optical switching of materials with perpendicular magnetic anisotropy is discussed.

Gram-negative bacteraemia; a multi-centre prospective evaluation of empiric antibiotic therapy and outcome in English acute hospitals.

Increasing antibiotic resistance makes choosing antibiotics for suspected Gram-negative infection challenging. This study set out to identify key determinants of mortality among patients with Gram-negative bacteraemia, focusing particularly on the importance of appropriate empiric antibiotic treatment. We conducted a prospective observational study of 679 unselected adults with Gram-negative bacteraemia at ten acute english hospitals between October 2013 and March 2014. Appropriate empiric antibiotic treatment was defined as intravenous treatment on the day of blood culture collection with an antibiotic to which the cultured organism was sensitive in vitro. Mortality analyses were adjusted for patient demographics, co-morbidities and illness severity. The majority of bacteraemias were community-onset (70%); most were caused by Escherichia coli (65%), Klebsiella spp. (15%) or Pseudomonas spp. (7%). Main foci of infection were urinary tract (51%), abdomen/biliary tract (20%) and lower respiratory tract (14%). The main antibiotics used were co-amoxiclav (32%) and piperacillin-tazobactam (30%) with 34% receiving combination therapy (predominantly aminoglycosides). Empiric treatment was inappropriate in 34%. All-cause mortality was 8% at 7 days and 15% at 30 days. Independent predictors of mortality (p <0.05) included older age, greater burden of co-morbid disease, severity of illness at presentation and inflammatory response. Inappropriate empiric antibiotic therapy was not associated with mortality at either time-point (adjusted OR 0.82; 95% CI 0.35-1.94 and adjusted OR 0.92; 95% CI 0.50-1.66, respectively). Although our study does not exclude an impact of empiric antibiotic choice on survival in Gram-negative bacteraemia, outcome is determined primarily by patient and disease factors.

Analysis of commonly reported medical conditions amongst patients receiving dental implant therapy in private practice.

BACKGROUND: The population seeking implants in private practice is a demographically and medically unique group. Understanding their medical needs can improve treatment planning and service delivery specifically for this population. METHODS: Privately practising dental clinicians from Victoria, Australia, participated in a five-year retrospective study. Data were collected from the medical histories of 4116 patients who met the inclusion criterion of at least one implant placed within the study period of 1 January 2005 to 31 December 2009. Descriptive statistics were used to describe patient demographics and commonly reported medical conditions. RESULTS: The most common age group to receive implant therapy was between 51 and 60 years (30.4% of patients). The patient population reported a broad range of co-morbidities including psychiatric disorders (83 patients), cardiovascular disorders (253 patients), gastrointestinal disorders (224 patients) and respiratory disorders (502 patients). Smoking was less prevalent amongst the study population compared to the general population. CONCLUSIONS: The population assessed in this study was a medically diverse group. Clinicians must be familiar with their target demographic and understand how the common co-morbidities amongst this patient group can influence clinical decision making and outcomes.

Survival rates and complication types for single implants provided at the Melbourne Dental School.

BACKGROUND: Single implants and implant-supported single crowns (ISSCs) have become popular treatment modalities for single tooth replacement. Studies have identified high implant survival rates, but also many complications. The aim of this five-year retrospective study was to assess the survival rates, complication types and occurrences for single implants and ISSCs at the Melbourne Dental School (MDS) in Victoria, Australia. METHODS: A search of the Royal Dental Hospital of Melbourne (RDHM) database was conducted for data on all implant treatment and reported complications during the period between 1 January 2005 and 31 December 2009. Complications were categorized into surgical, biological and restorative types. RESULTS: A total of 622 implant fixtures and 444 ISSCs were inserted into 406 patients. Seventeen implants failed during the mean follow-up time of 2.18 years, yielding a 2.7% failure rate and an estimated one- and five-year survival rate of 98.8% and 93.9%, respectively. The cumulative surgical, biological and restorative complication incidences were 11.9%, 17.6% and 14.1%, respectively. CONCLUSIONS: This study confirmed that single tooth replacement using implant therapy within a teaching environment had a high survival rate. However, complications frequently occurred. This article only provides a descriptive analysis. Correlation analysis between variables would provide greater insight into the causes of complications.

The kidney as a new target for antidiabetic drugs: SGLT2 inhibitors.

WHAT IS KNOWN AND OBJECTIVE: A novel class of antidiabetic drugs - SGLT2 (Na(+) /glucose cotransporter type 2) inhibitors - target renal reabsorption of glucose and promote normal glucose levels, independent of insulin production or its action at receptors. We review this new mechanistic approach and the reported efficacy and safety of clinical testing of lead compounds. METHODS: Information was obtained from various bibliographic sources, including PubMed and others, on the basic science and the clinical trials of SGLT2 inhibitors. The information was then summarized and evaluated from the perspective of contribution to a fuller understanding of the potential and current status of the lead clinical candidates. RESULTS AND DISCUSSION: Diabetes mellitus is a spectrum of disorders that involves inadequate insulin function resulting in adverse health sequelae due to acute and chronic hyperglycaemia. Current antidiabetic pharmacotherapy primarily addresses either insulin production at the pancreatic ß-cells or insulin action at insulin receptors. These drugs have less than full clinical effectiveness and sometimes therapy-limiting adverse effects. The third major component of glucose balance, namely elimination, has not been a significant therapeutic target to date. SGLT2 inhibitors are a novel approach. WHAT IS NEW AND CONCLUSION: A sufficient number of clinical trials have been conducted on sufficiently chemically diverse SGLT2 inhibitors to reasonably conclude that they have efficacy (HbA1c reductions of 0·4-1%), and thus far, the majority of adverse effects have been mild and transitory or treatable, with the caveat of possible association with increased risk of breast cancer in women and bladder cancer in men.

Vitamin D and type 2 diabetes mellitus.

WHAT IS KNOWN AND OBJECTIVE: The deleterious effect of vitamin D deficiency on bone health has long been known. More recent studies suggest a deleterious effect of low vitamin D (hypovitaminosis D) on general health. And specific studies propose an association between hypovitaminosis D and the aetiology and progression of type 2 diabetes (T2DM). Given a commonly assumed lack of toxicity of vitamin D, routine measurement of plasma vitamin D and supplementation is rapidly becoming accepted general practice. COMMENT: Authoritative practice guidelines have raised the level of vitamin D that is to be considered minimal for optimum health. This recommendation was based on a wealth of information and definitive evidence for skeletal benefits of vitamin D, but there was a lack of compelling evidence that hypovitaminosis D is causally related to extra-skeletal health outcomes such as diabetes. Hence, vitamin D supplementation for the purpose of achieving a level consistent with good health is evidence based, but measurement and supplementation for the purpose of preventing or treating T2DM is not. WHAT IS NEW AND CONCLUSION: Although the maintenance of adequate vitamin D levels is desirable for all patients, we conclude that routine measurement of vitamin D level in every patient or initiating high-dose supplementation for the purpose of preventing or treating T2DM is not evidence based.

Strategies for restoration of single implants and use of cross-pin retained restorations by Australian prosthodontists.

BACKGROUND: Implant supported restorations (ISRs) for the single implant may be cement retained or screw retained. Limited scientific evidence exists to support the superiority of a retention type for either implant or prosthetic success. The aim of this study was to assess preferences of Australian prosthodontists when restoring single implants. In particular, clinical practices for cross-pin retained implant supported restorations for a single implant were investigated. METHODS: A written questionnaire comprised of seven questions, some of which had multiple parts and of both open- and closed-format, was sent to 124 Australian prosthodontists. The questionnaire asked recipients to identify: (1) their preference for retention choice when restoring a single implant; (2) the frequency of use; and (3) clinical practice when restoring a cross-pin retained restoration. RESULTS: Seventy-seven per cent of respondents indicated that direct to fixture (DTF) retention was their first preference. DTF retention was also the most frequently employed restoration for single implants. Respondents indicated that cross-pinned ISRs are employed to maintain retrievability or when DTF is not possible. The majority of respondents indicated they always or sometimes use a gasket with cross-pin retained restorations, though gasket type varied. Thirty-eight respondents (31%) indicated that they would never use a cross-pinned retained restoration for a single ISR. CONCLUSIONS: Australian prosthodontists prefer, and more frequently restore single implants, using DTF retention. Queensland prosthodontists prefer cement retained ISRs. In comparison, cross-pinned restorations tend to be the least favoured and least used retention type. In addition, variation in opinion exists regarding the need for a gasket and type of gasket to be placed.

The cross-pin retained implant supported restoration: a study of gasket placement and leakage.

BACKGROUND: Advantages of cross-pin retained implant supported restorations (ISRs) include predictable retrieval and predictable retention. Unlike direct to fixture (DTF) or cement retained restorations, the prosthetic design of a cross-pinned restoration retains gaps at the interfaces between the crown, abutment and cross-pin screw. These spaces permit leakage into the suprastructure and gasket placement has been recommended to prevent this leakage. METHODS: Five different gaskets were assessed for their ability to prevent leakage into a cross-pinned ISR. The gaskets tested were: cement admixture on the cross-pin screw; cement admixture on the inner surface of the coping and the cross-pin screw; cement admixture on the inner surface of the coping only; cement admixture placed 1 mm from the margin of the coping and a filler placed in the abutment chimney. results: Only gaskets which sealed both the cross-pin screw interface and the abutment-crown interface prevented leakage. A filler placed in the abutment chimney prevented leakage into this space but did not prevent fluid accumulating between the coping and abutment. Conservative placement of cement at the margin of the coping failed to prevent leakage. CONCLUSIONS: Cement gaskets may effectively prevent leakage into a cross-pinned ISR. However, the use of a cement as a gasket has to be weighed against the issue of predictable retrieval, cement extrusion and incomplete seating.

Contribution to the analysis of the predissociated rovibronic structure of the symmetric isotopomers 16O3 and 18O3 of ozone near 10,400 cm-1): [3A2(3(2)(0)) <-- X1A1(0(0)(0))] and 3B2 <-- X1A1.

The absorption spectrum of ozone was recorded at low temperatures (down to -135 degrees C) by high resolution Fourier transform spectrometry and intra cavity laser absorption spectroscopy (ICLAS) near 10,400 cm-1. A preliminary analysis of the rotational structure of the absorption spectra of 16O3 and 18O3 shows that this spectral region corresponds to a superposition of two different electronic transitions, one with a very broad rotational structure, showing for the first time the asymmetric stretching frequency mode nu3 of the electronic state 3A2, the other formed by a completely diffuse band, probably the 2(1)(0) band of a new transition due to the triplet electronic state 3B2. Predissociation effects induce large broadening of the rotational lines for the transition centered at 10,473 cm-1 identified as the 3(2)(0) band of the 3A2 <-- X1A1 electronic transition. The rotational structure cannot be analyzed directly but instead the band contour method was used to confirm the symmetry of the transition and to estimate the spectroscopic constants for the 16O isotopomer. The origin of the band is at 10,473 +/- 3 cm-1 and the value of the 16O3(3A2) antisymmetric stretching frequency mode is equal to 460 +/- 2 cm-1. We believe that the diffuse band is due to the 3B2 state and is located at about 10,363 +/- 3 cm-1 for 16O3 and 10,354 +/- 3 cm-1 for 18O3. The isotopic rules confirm the different results obtained for 18O3 and 16O3.

Discontinuation symptoms: comparison of brief interruption in fluoxetine and paroxetine treatment.

Abrupt interruption or cessation of selective serotonin reuptake inhibitor (SSRI) treatment may result in discontinuation or treatment interruption symptoms. Recent reports suggested these symptoms occur more frequently with shorter half-life SSRIs. Previous studies indicated a 5-8-day treatment interruption resulted in fewer discontinuation-emergent adverse events in fluoxetine-treated patients than in paroxetine-treated patients. This study examines the effects of shorter treatment interruption (3-5 days), as would occur if patients miss just a few doses of medication. Patients successfully treated for depression with fluoxetine or paroxetine underwent treatment interruption in a double-blind fashion. Treatment interruption-emergent symptoms were assessed using the Discontinuation-Emergent Signs and Symptoms checklist. Other assessments included the Montgomery-Asberg Depression Rating Scale, Clinical Global Impressions-Severity scale and a social functioning questionnaire. Of 150 patients enrolled, 141 completed the study. Following treatment interruption, fluoxetine-treated patients experienced fewer treatment interruption-emergent events than did paroxetine-treated patients. The paroxetine treatment group also experienced significant increases in depressive symptoms, clinical global severity scores and difficulty in social functioning; the fluoxetine treatment group did not. These results are consistent with reports suggesting abrupt interruption of treatment with paroxetine is more often associated with somatic and psychological symptoms than is abrupt interruption of fluoxetine. Patients treated with fluoxetine appeared to be protected by its longer half-life.

Using a multimedia tool to improve cardiac auscultation knowledge and skills.

OBJECTIVE: Today's medical school graduates have significant deficits in physical examination skills. Medical educators have been searching for methods to effectively teach and maintain these skills in students. The objective of this study was to determine if an auscultation curriculum centered on a portable multimedia CD-ROM was effective in producing and maintaining significant gains in cardiac auscultatory skills. DESIGN: Controlled cohort study. PARTICIPANTS: All 168 third-year medical students at 1 medical school in an academic medical center. INTERVENTIONS: Students were tested before and after exposure to 1 or more elements of the auscultation curriculum: teaching on ward/clinic rotations, CD-ROM comprehensive cases with follow-up seminars, and a CD-ROM 20-case miniseries. The primary outcome measures were student performance on a 10-item test of auscultation skill (listening and identifying heart sound characteristics) and a 30-item test of auscultation knowledge (factual questions about auscultation). A subset of students was tested for attenuation effects 9 or 12 months after the intervention. RESULTS: Compared with the control group (1 month clinical rotation alone), students who were also exposed to the CD-ROM 20-case miniseries had significant improvements in auscultation skills scores (P < .05), but not knowledge. Additional months of clerkship, comprehensive CD-ROM cases, and follow-up seminars increased auscultation knowledge beyond the miniseries alone (P < .05), but did not further improve auscultation skills. Students' auscultation knowledge diminished one year after the intervention, but auscultation skills did not. CONCLUSION: In addition to the standard curriculum of ward and conference teaching, portable multimedia tools may help improve quality of physical examination skills.

Treatment recommendations versus treatment realities: recognizing the rift and understanding the consequences.

Depression is a treatable disorder, although it often requires long-term therapy. To aid physicians in the effective long-term management of depression, treatment guidelines have been established by a number of organizations with minimum treatment duration recommendations. Unfortunately, numerous studies document a significant disparity between these recommendations and clinical practice realities. In particular, studies have shown that fewer than half of treated patients receive the recommended duration of 6 months of continuation therapy. Other clinical practice studies have reported that early discontinuation from therapy is associated with a substantial increase in the risk of relapse or recurrence. Long-term treatment of depression in clinical practice settings may benefit from a closer approximation to the conditions found in clinical trial settings.

Patient perspectives on once-weekly fluoxetine.

BACKGROUND: Continuation therapy is recommended for 4 to 9 months following remission of symptoms of major depressive disorder. Long-term maintenance therapy is recommended for patients with severe, recurrent symptoms. However, most patients do not complete an adequate course of therapy. We investigated patient perceptions of antidepressant dosing to determine whether weekly dosing could provide an additional tool to help more patients remain compliant with antidepressant treatment. METHOD: Physicians were asked to complete an anonymous patient profile for 7 patients currently receiving antidepressant treatment and to give those patients a questionnaire that the patients could submit anonymously. In addition, clinically depressed patients in the United States and in France were surveyed by telephone. RESULTS: Patients surveyed by questionnaire agreed most strongly with statements indicating that they would like their doctor to involve them in the choice of antidepressant medication, that they did not want others to know they were taking antidepressant medication, and that they disliked the idea of taking daily medication. Patients in the telephone survey agreed most strongly with statements indicating that they considered once-weekly dosing more convenient than daily dosing, that they believed taking 1 pill a week would make them feel less dependent on pills, and that they perceived more advantages than disadvantages in taking 1 pill a week. CONCLUSION: Weekly antidepressant treatment may provide an effective tool in helping patients with depression. Positive patient perceptions of weekly dosing suggest that some patients may remain on continuation or maintenance therapy longer when they have the option of weekly dosing.

Fluoxetine in the prevention of depressive recurrences: a double-blind study.

Optimal outcomes from depression treatment are long-term recovery and, in the case of recurrent depression, prevention of new episodes. However, few data are available concerning the long-term efficacy of antidepressants in prophylactic treatment to prevent recurrences of depression. The efficacy and safety of fluoxetine 20 mg/day was evaluated in reducing the number of depressive episodes and in extending the time free of symptoms in patients with recurrent unipolar major depression. Patients with recurrent unipolar major depression according to DSM-III-R criteria and who responded to 32 weeks of open-label fluoxetine were randomly assigned to receive fluoxetine 20 mg/day (N = 70) or placebo (N = 70) for 48 weeks of double-blind maintenance treatment. Outcome measures were the percentage of recurrences and time to recurrence. Safety assessments included treatment-emergent adverse events, reasons for discontinuation, vital signs, and laboratory measures. Fluoxetine was associated with a statistically significantly smaller percentage of patients who had a recurrence compared with placebo (20% vs. 40%; chi2 analysis, p = 0.010). The symptom-free period was significantly longer for patients treated with fluoxetine versus placebo (295 vs. 192 days; Kaplan-Meier estimates, log-rank test, p = 0.002). Treatments were well tolerated during maintenance treatment. The only statistically significant difference in adverse events between treatment groups was anxiety, which was more frequent in the placebo group (fluoxetine, 12.9% vs. placebo, 30%; chi2 analysis, p = 0.013). Two placebo-treated patients and no fluoxetine-treated patients were withdrawn because of adverse events. In conclusion, fluoxetine at 20 mg/day was effective and well tolerated for the prophylactic treatment of recurrent unipolar major depression.

The efficacy of fluoxetine in improving physical symptoms associated with premenstrual dysphoric disorder.

OBJECTIVE: To determine the effectiveness of fluoxetine in alleviating physical symptoms of premenstrual dysphoric disorder. DESIGN: Randomised, double-blind, placebo controlled, parallel study. SETTING: Canadian University based outpatient clinics. Participants Four hundred and five subjects, of whom 320 with prospectively determined premenstrual dysphoric disorder were randomised. METHODS: Randomised women were assigned to fluoxetine 20 or 60 mg/day or placebo. Common physical symptoms associated with premenstrual dysphoric disorder including breast tenderness, bloating, and headache were evaluated by visual analog scales and the self-rated and observer premenstrual tension syndrome scales. OUTCOME MEASURES: Luteal phase change from mean baseline scores to mean treatment scores for all scales. RESULTS: Fluoxetine treatment was statistically superior to placebo, with no significant differences between the two fluoxetine dosages in their effects on physical symptoms. CONCLUSION: Daily fluoxetine treatment is superior to placebo in improving the most common physical symptoms associated with premenstrual dysphoric disorder.