Direct access:how is it working?

AimThe aim of this study was to identify and survey dental hygienists and therapists working in direct access practices in the UK, obtain their views on its benefits and disadvantages, establish which treatments they provided, and what barriers they had encountered.MethodThe study used a purposive sample of GDC-registered hygienists and therapists working in practices offering direct access, identified through a ‘Google’ search. An online survey was set up through the University of Edinburgh, and no-responses followed up by post.ResultsThe initial search identified 243 individuals working in direct access practices. Where a practice listed more than one hygienist/therapist, one was randomly selected. This gave a total of 179 potential respondents. Eighty six responses were received, representing a response rate of 48%. A large majority of respondents (58, 73%) were favourable in their view of the GDC decision to allow direct access, and most thought advantages outnumbered disadvantages for patients, hygienists, therapists and dentists. There were no statistically significant differences in views between hygienists and therapists. Although direct access patients formed a small minority of their caseload for most respondents, it is estimated that on average respondents saw approximately 13 per month. Treatment was mainly restricted to periodontal work, irrespective of whether the respondent was singly or dually qualified. One third of respondents reported encountering barriers to successful practice, including issues relating to teamwork and dentists’ unfavourable attitudes. However, almost two thirds(64%) felt that direct access had enhanced their job satisfaction, and 45% felt their clinical skills had increased.DiscussionComments were mainly positive, but sometimes raised worrying issues, for example in respect to training, lack of dental nurse support and the limited availability of periodontal treatment under NHS regulations

Effect of Canal Length and Curvature on Working Length Alteration with WaveOne Reciprocating Files

The article “Effect of Canal Length and Curvature on Working Length Alteration with WaveOne Reciprocating Files” by Elio Berutti, Giorgio Chiandussi, Davide Salvatore Paolino, Nicola Scotti, Giuseppe Cantatore, Arnaldo Castellucci and Damiano Pasqualini (J Endod 37[12]:1687–90; 2011] should have included this statement in the author information section: “Giuseppe Cantatore, Arnaldo Castellucci, and Elio Berutti declare that they have financial involvement (patent licensing arrangements) with Dentsply Maillefer with direct financial interest in the materials discussed in this article.” In addition, Dentsply provided some of the instruments used in this study." The authors regret this omission

Reducing cannabinoid abuse and preventing relapse by enhancing endogenous brain levels of kynurenic acid

In the reward circuitry of the brain, alpha-7-nicotinic acetylcholine receptors (α7nAChRs) modulate effects of delta-9-tetrahydrocannabinol (THC), marijuana’s main psychoactive ingredient. Kynurenic acid (KYNA) is an endogenous negative allosteric modulator of α7nAChRs. Here we report that the kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 increases brain KYNA levels and attenuates cannabinoid-induced increases in extracellular dopamine in reward-related brain areas. In the self-administration model of drug abuse, Ro 61-8048 reduced the rewarding effects of THC and the synthetic cannabinoid WIN 55,212-2 in squirrel monkeys and rats, respectively, and it also prevented relapse to drug-seeking induced by re-exposure to cannabinoids or cannabinoid-associated cues. The effects of enhancing endogenous KYNA levels with Ro 61-8048 were prevented by positive allosteric modulators of α7nAChRs. Despite a clear need, there are currently no medications approved for treatment of marijuana dependence. Modulation of KYNA provides a novel pharmacological strategy for achieving abstinence from marijuana and preventing relapse

An Open-Label, Multicenter Observational Study for Patients with Alzheimer's Disease Treated with Memantine in the Clinical Practice

Background/Aims: In this post-marketing observational study, the safety and effectiveness of memantine were evaluated in patients with Alzheimer’s disease (AD). Methods: In a 6-month, observational, open-label study at 202 specialist sites in Greece, the effectiveness of memantine was evaluated using the Mini-Mental State Examination (MMSE) and the Instrumental Activities of Daily Living (IADL) scale at baseline, and after 3 and 6 months. Discontinuation rates and adverse drug reactions (ADRs) were also recorded to evaluate the safety profile of memantine. Results: 2,570 patients participated in the study. Three and 6 months after baseline, MMSE and IADL scores were significantly improved compared to baseline. At the end of the study, 67% of the patients had improved their MMSE score; 7.1% of the patients reported ≧1 ADRs, and treatment was discontinued due to ADR in 0.7%. Conclusion: Memantine was well tolerated and had a positive effect on the patient’s cognitive and functional ability in real-life clinical practice, in agreement with randomized, controlled trials

Cytotoxicity of Selected Nanoparticles on Human Dental Pulp Stem Cells

Introduction: Nanoparticles are being increasingly applied in dentistry due to their antimicrobial and mechanical properties. This in vitro study aimed to assess and compare the cytotoxicity of four metal oxide nanoparticles (TiO2, SiO2, ZnO, and Al2O3) on human dental pulp stem cells. Methods and Materials: Four suspension with different concentrations (25, 50, 75, 100 µg/mL) of each nanoparticle were prepared and placed into cavities of three 96-well plates (containing 1×104 cells per well that were seeded 24 earlier). All specimens were incubated in a humidified incubator with 5% CO2 at 37°C. Mosmann’s Tetrazolium Toxicity (MTT) assay was used to determine in vitro cytotoxicity of test materials on pulpal stem cells. Cell viability was determined at 24, 48, and 72 h after exposure. Data comparisons were performed using a general linear model for repeated measures and Tukey's post hoc test. The level of significance was set at 0.05. Results: The tested nanoparticles showed variable levels of cytotoxicity and were dose and time dependant. The minimum cell viability was observed in ZnO followed by TiO2, SiO2 and Al2O3. Conclusion: The results demonstrated that cell viability and morphological modifications occurred at the concentration range of 25 to 100 µg/mL and in all nanoparticles. The higher concentration and longer duration of exposure increased cellular death. Our results highlight the need for a more discrete use of nanoparticles for biomedical applications.Keywords: Cytotoxicity; Dental Pulp Stem Cells; Metal Oxide Nanoparticle

Morphological, histochemical, and interstitial pressure changes in the tibialis anterior muscle before and after aortofemoral bypass in patients with peripheral arterial occlusive disease

BACKGROUND: Morphological and electrophysiological studies of ischemic muscles in peripheral arterial disease disclosed evidence of denervation and fibre atrophy. The purpose of the present study is to describe morphological changes in ischemic muscles before and after reperfusion surgery in patients with peripheral occlusive arterial disease, and to provide an insight into the effect of reperfusion on the histochemistry of the reperfused muscle. METHODS: Muscle biopsies were obtained from the tibialis anterior of 9 patients with chronic peripheral arterial occlusive disease of the lower extremities, before and after aortofemoral bypass, in order to evaluate the extent and type of muscle fibre changes during ischemia and after revascularization. Fibre type content and muscle fibre areas were quantified using standard histological and histochemical methods and morphometric analysis. Each patient underwent concentric needle electromyography, nerve conduction velocity studies, and interstitial pressure measurements. RESULTS: Preoperatively all patients showed muscle fibre atrophy of both types, type II fibre area being more affected. The mean fibre cross sectional area of type I was 3,745 μm(2) and of type II 4,654 μm(2) . Fibre-type grouping, great variation in fibre size and angular fibres were indicative of chronic dennervation-reinnervation, in the absence of any clinical evidence of a neuropathic process. Seven days after the reperfusion the areas of both fibre types were even more reduced, being 3,086 μm(2) for type I and 4,009 μm(2) for type II, the proportion of type I fibres, and the interstitial pressure of tibialis anterior were increased. CONCLUSIONS: The findings suggest that chronic ischemia of the leg muscles causes compensatory histochemical changes in muscle fibres resulting from muscle hypoxia, and chronic dennervation-reinnervation changes, resulting possibly from ischemic neuropathy. Reperfusion seems to bring the oxidative capacity of the previously ischemic muscle closer to normal

Root canal instrumentation efficacy of non-fused and fused primary molar roots:a micro-computed tomography study

Purpose Pulpectomy may be indicated in restorable primary teeth exhibiting irreversible pulpitis or pulpal necrosis. The purpose of this study was to compare the cleaning and shaping efficacy of NiTi systems (Reciproc(R) Blue and MTwo(R)) with manual stainless-steel instrumentation in primary molars using micro-CT analysis. Methods Fifty-seven maxillary second primary molars were scanned using micro-CT. Teeth with three divergent roots were divided randomly (n = 15) according to instrument type (K file, MTwo (R), and Reciproc (R) Blue). Teeth with root fusion were instrumented manually as a separate group (n = 12). Pre- and post-instrumentation micro-CT images were superimposed, and the instrumentation area (IA) and procedural complications were recorded. Results No statistically significant differences in IA between file systems was observed in the non-fused teeth. The mean IA of fused roots was significantly lower than in the non-fused distobuccal (p = 0.003) and palatal (p 60%) occurred in both non-fused and fused primary teeth with fewer procedural complications observed after manual instrumentation

Biocompatibility and hard tissue-forming ability of CPP-ACP- and CPP- ACFP-modified calcium silicate-based cements

Aims: To evaluate the biocompatibility and osteogenic potential of calcium silicate-based cements (CSCs) modified with casein phosphopeptide – amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide – amorphous calcium fluoride phosphate (CPP-ACFP). Materials and method: Commercially available CSCs were modified with CPP-ACP or CPP-ACFP to prepare CPP-ACP and CPP-ACFP-modified Biodentine™ (0%, 0.5%, 4.0% w/w), Angelus® MTA (0%, 0.5%, 2.0% w/w) and NEX® MTA (0%, 0.5%, 3.0% w/w). For each group, 50 mg, 300 mg and 1500 mg of the cement mixed according to manufacturers’ instructions were placed and adapted at the bottom of 96 well, 24 well and 6 well (respectively) cell culture plates. After 24 h, the cement-coated plates were sterilised by ultraviolet light for 1 h. MG-63, MC3T3-E1, HGF-1, NIH3T3 cells were grown in the cement-coated plates and the cellular proliferation, cellular toxicity, alkaline phosphatase activity, cytokine production (interleukin-1α; IL-1α and interleukin-6; IL-6) and expression of mineralisation-associated proteins (collagen type 1, osteocalcin and osteopontin) were determined. Results: The addition of 0.5% CPP-ACP and 4.0% CPP-ACFP to Biodentine™, and 2.0% CPP-ACFP to Angelus® MTA significantly reduced the proliferation of MG-63. The addition of 4.0% CPP-ACP and 4.0% CPP-ACFP to Biodentine™, 2.0% CPP-ACFP to Angelus® MTA and 3.0% CPP-ACFP to NEX® MTA significantly reduced the proliferation of MC3T3-E1 cells. The tested cements, with and without CPP-ACP and CPP-ACFP, did not induce cellular toxicity nor IL-1α release. The addition of CPP-ACP and CPP-ACFP to Biodentine™ and NEX® MTA, and the addition of CPP-ACP to Angelus® MTA significantly increased the alkaline phosphatase activity of MG-63 cells. The presence of 4.0% CPP-ACP in Biodentine™, 0.5% and 2.0% CPP-ACP in Angelus® MTA, 0.5% CPP-ACFP in Angelus® MTA, and 0.5% CPP-ACFP in NEX® MTA significantly increased the alkaline phosphatase activity of MC3T3-E1 cells. All the tested cements significantly increased the release of IL-6 from MG-63 compared with negative control. The presence of CPP-ACP and CPP-ACFP in NEX® MTA significantly increased the release of IL-6 from MG-63 compared with unmodified NEX® MTA. MC3T3-E1 cells grown on Biodentine™ (unmodified and modified groups) and 3.0% CPP-ACFP-modified NEX® MTA released significantly higher IL-6 compared with negative control. 0.5% CPP-ACFP-modified Biodentine™ and 3.0% CPP-ACFP-modified NEX® MTA induced significantly higher IL-6 release from MC3T3-E1 compared with unmodified Biodentine™ and unmodified NEX® MTA respectively. The tested cements (especially Biodentine™, Angelus® MTA and CPP-ACFP-modified cements) induced the secretion of mineralisation-associated proteins (especially collagen type 1 and osteocalcin).Conclusions: The tested cements are biocompatible, and they could serve as a suitable scaffold which supports cellular proliferation. The addition of CPP-ACP and CPP-ACFP to CSCs improved the cements’ potential to induce osteoblastic differentiation

Evaluation of the Total Design Method in a survey of Japanese dentists

BACKGROUND: This study assessed the application of the Total Design Method (TDM) in a mail survey of Japanese dentists. The TDM was chosen because survey response rates in Japan are unacceptably low and the TDM had previously been used in a general population survey. METHODS: Four hundred and seventy eight dentist members of the Okayama Medical and Dental Practitioner's Association were surveyed. The nine-page, 27-item questionnaire covered dentist job satisfaction, physical practice, and dentist and patient characteristics. Respondents to the first mailing or the one-week follow-up postcard were defined as early responders; others who responded were late responders. Responder bias was assessed by examining age, gender and training. RESULTS: The overall response rate was 46.7% (223/478). The response rates by follow-up mailing were, 18% after the first mailing, 35.4% after the follow-up postcard, 42.3% after the second mailing, and 46.7% after the third mailing. Respondents did not differ from non-respondents in age or gender, nor were there differences between early and late responders. CONCLUSION: The application of TDM in this survey of Japanese dentists produced lower rates of response than expected from previous Japanese and US studies