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Key points In herbivores, including guinea pigs, clearly defined faecal pellets are formed at a distinct location along the large intestine (colonic flexure). The mechanism underlying formation of these faecal pellets at this region has remained, until now, a major unresolved issue. We reveal a progressive and gradual reduction in water content of faecal content along the bowel. Hence, the distinct transition from amorphous to pellet shaped faecal content could not be explained by a dramatic increase in water reabsorption from a specific site. We discovered novel patterns of anterograde neurogenic and retrograde myogenic motor activity that facilitate the formation of faecal pellets. The formation of "pellet-like" boluses at the colonic flexure involves the interaction of an antegrade migrating motor complex in the proximal colon and retrograde myogenic slow phasic contractions at the colonic flexure. The findings uncover major new intrinsic mechanisms responsible for the formation of discrete faecal scybala in the large intestine of a vertebrate. Abstract Soft faecal material is transformed into discrete, pellet-shaped faeces at the colonic flexure. Here, analysis of water content in natural faecal material revealed a decline from cecum to rectum without significant changes at the flexure. Thus, pellet formation is not explained by changes in viscosity alone. We then used video imaging of colonic wall movements with electromyography in isolated preparations containing guinea-pig proximal colon, colonic flexure and distal colon. To study the pellet formation process, the colonic segments were infused with artificial contents (Krebs solution and 4-6% methylcellulose) to simulate physiological faecal content flow. Remarkably, pellet formation took place in vitro, without extrinsic neural inputs. Infusion evoked slowly propagating neurogenic contractions, the proximal colonic migrating motor complexes (∼0.6cpm), which initiated pellet formation at the flexure. Lesion of the flexure, but not the proximal colon, disrupted formation of normal individual pellets. In addition, a distinct myogenic mechanism was identified, whereby slow phasic contractions (∼1.9cpm) initiated at the flexure and propagated short distances retrogradely into the proximal colon and antegradely into the distal colon. There were no detectable changes in the density or distribution of pacemaker-type Interstitial Cells of Cajal across the flexure. The findings provide new insights into how solid faecal content is generated, suggesting the major mechanisms underlying faecal pellet formation involve the unique interaction at the colonic flexure between antegrade PCMMCs, organized by enteric neurons, and retrograde myogenic SPCs. Additional, as yet unidentified extrinsic and/or humoral influences appear to contribute to processing of faecal content, in vivo. This article is protected by copyright. All rights reserved.

Purpose The aim of this retrospective study is to determine children’s attendance and experience of preventative interventions and operative treatment (restorations and extractions) with their primary care dentist (PCD) in the 12 months before and after their caries management under dental general anaesthetic (DGA). Methods A record of all children who had an elective DGA in 2016 across two hospital sites was retrospectively obtained (n = 1308). A representative sample of 300 was randomly selected encompassing 114 dental practices. An online questionnaire to the children’s PCDs collated quantitative and qualitative data regarding participation in the pre- and post-DGA period. Results Data was collated and analysed for 80 children (mean age: 6 years 10 months [SD = 2.49; range: 2 years 1 month – 14 years 3 months]; equal sex distribution) with 43 responding PCDs. Attendance for examination declined significantly from 85% (n = 68) pre-DGA to 57.5% (n = 46) post-DGA (p ≤ 0.001). Attendance at emergency appointments pre-DGA was high (33.75% [n = 27]); a significant reduction post-DGA was recorded (p ≤ 0.001). Over one third of children (37.5% [n = 30]) did not receive any form of preventative intervention over 24 months. A non-significant reduction in the provision of operative treatment was observed post-DGA (p = 0.06 [fill, primary]; p = 0.78 [fill, permanent]; p = 0.66 [ext, primary]). No statistical difference between age and treatment experience was found. Qualitative analysis revealed challenges in providing care included behavioural difficulties and poor attendance. Conclusion Improvements are required in strategies employed to support high caries risk children pre- and post-DGA to facilitate a higher incidence of attendance and preventative intervention with PCDs.

Colonic motor complexes (CMCs) are a major neurogenic activity in guineapig distal colon. The identity of the enteric neurons that initiate this activity is not established. Specialized intrinsic primary afferent neurons (IPANs) are a major candidate. We aimed to test this hypothesis. To do this, segments of guineapig distal colon were suspended vertically in heated organ baths and propulsive forces acting on a pellet inside the lumen were recorded by isometric force transducer while pharmacological agents were applied to affect IPAN function. In the absence of drugs, CMCs acted periodically on the pellet, generating peak propulsive forces of 12.7 ± 5 g at 0.56 ± 0.22 cpm, lasting 49 ± 17 s (215 preparations

Key points Enteric neural circuits enable isolated preparations of guinea-pig distal colon to propel solid and fluid contents by a self-sustaining neuromechanical loop process. In addition there are at least three neural mechanisms which are not directly involved in propulsion: cyclic motor complexes, transient neural events and distal colon migrating motor complexes. In excised guinea-pig colon we simultaneously recorded high resolution manometry, video-imaging of colonic wall movements and electrophysiological recordings from smooth muscle, which enabled us to identify mechanisms that underlie the propulsion of colonic content. The results show that the intermittent propulsion during emptying of the multiple natural faecal pellets is due to the intermittent activation of cyclic motor complexes and this is facilitated by transient neural events. Loss or dysfunction of these activities is likely to underlie disordered gastrointestinal transit. Abstract It is well known that there are different patterns of electrical activity in smooth muscle cells along different regions of the gastrointestinal tract. These different patterns can be generated by myogenic and/or neurogenic mechanisms. However, what patterns of electrical activity underlie the propulsion of natural faecal content remains unknown, particularly along the large intestine, where large quantities of water are reabsorbed and semi-solid faeces form. In this study, we developed a novel approach which enables for the first time the simultaneous recording of high resolution intraluminal manometry, electrophysiology from the smooth muscle, and spatio-temporal video imaging of colonic wall movements. Using this approach we were able to reveal the nature of enteric neuromuscular transmission and patterns of motor activity responsible for the movement of content. Three distinct neurogenic patterns of electrical activity were recorded even in the absence of propulsive movement. These were the cyclic motor complexes (CMCs), the transient neural events (TNEs) and the slowly propagating distal colonic migrating motor complexes (DCMMCs). We present evidence that the initiation of pellet propulsion is due to a cyclic motor complex (CMC) occurring oral to the pellet. Furthermore, we discovered that the intermittent propulsion of natural faecal pellets is generated by intermittent activation of CMCs; and this propulsion is facilitated by hexamethonium-sensitive TNEs. However, TNEs were not required for propulsion. The findings reveal the patterns of electrical activity that underlie propulsion of natural colonic content and demonstrate that propulsion is generated by a complex interplay between distinct enteric neural circuits.

Neural mechanisms of lower urinary tract symptoms in obstruction-induced bladder overactivity remain unclear. We made the first single unit recordings from different types of spinal afferents to determine the effects of bladder outlet obstruction in guinea pigs. A model of gradual bladder outlet obstruction in male guinea pigs was used to produce overactive bladder. Conscious voiding was assessed in metabolic cages, and micturition was recorded in anesthetized guinea pigs in vivo. Single unit extracellular recordings were made ex vivo from spinal afferent nerves in flat sheet preparations of the bladder. Guinea pigs with partially obstructed bladders showed a significant increase in conscious voiding frequency compared with sham-operated guinea pigs. Also, nonvoiding contractions increased significantly in both frequency and amplitude. Although spontaneous firing of low-threshold bladder afferents was increased, their stretch-induced firing was reduced. The proportion of capsaicin-sensitive low-threshold afferents increased in obstructed bladders. Interestingly, spontaneous and stretch-induced firing were both significantly increased in high-threshold afferents after obstruction. In summary, sensory signaling increased in the obstructed bladder during the filling phase. This is largely mediated by low-threshold stretch-sensitive afferents that are activated by increased local nonvoiding contractions. Increased spontaneous firing by high-threshold afferents also contributes. Our findings revealed a complex effect of bladder outlet obstruction on different types of bladder afferents that needs consideration for potential therapeutic targeting of lower urinary tract symptoms in obstruction-induced bladder overactivity.

Background In herbivores, the proximal and distal colonic regions feature distinct motor patterns underlying formation and propulsion of fecal pellets, respectively. Omnivores, such as mice and humans, lack a similar clear anatomical transition between colonic regions. We investigated whether distinct processes form and propel content along the large intestine of a mouse (an omnivore). Methods We recorded propulsive and non-propulsive neurogenic motor activity in mouse large intestine under six different stimulus conditions of varying viscosities. Gut wall movements were recorded by video and smooth muscle electrical behavior recorded with extracellular suction electrodes. Key results Three major neurally mediated motor patterns contributed to pellet formation and propulsion. (1) Pellet-shaped boluses are pinched off near the ceco-colonic junction and slowly propelled distally to a transition located at 40% length along the colon. (2) At this functional colonic flexure, propulsion speed is significantly increased by self-sustaining neural peristalsis. Speed transition at this location also occurs with artificial pellets and with spontaneously formed boluses in the empty colon. (3) Periodic colonic motor complexes (CMCs) were present in all conditions reaching a maximal frequency of about 0.4 cpm and extending across the proximal and distal colon with faster speed of propagation. Conclusions and inferences The three motor patterns share a unique underlying fundamental property of the enteric circuits, which involve extended ensembles of enteric neurons firing at close to 2 Hz. The demonstration of distinct functional differences between proximal and distal colon in rabbit, guinea pig, and now mouse raises the possibility that this may be an organizational principle in other mammalian species, including humans.

Background: Different genes and loci that are associated with non-syndromic developmental tooth agenesis (TA) have the same causation pathway in the development of tumours including breast cancer (BC), epithelial ovarian cancer (EOC), colorectal cancer (CRC) and lung cancer (LC). Objectives: To assess the link between TA and the development of cancer. Search sources: This registered review included a comprehensive search of electronic databases (Cochrane Central Register of Controlled Trials [CENTRAL], LILACS, Scopus, Web of Science and Medline via Ovid) until 1 April 2020, supplemented by manual, grey literature and reference lists search. There was no restriction in term of date of publication, gender, race or type of hypodontia. Data selection: The primary outcome was the relationship between TA and cancer. The secondary outcome was to identify the genetic correlation between TA and cancer. Data extraction: Study selection, data extraction and risk of bias assessment were performed independently and induplicate by two reviewers, with disputes resolved by a third reviewer. Results: Eight studies with a moderate-high risk of bias were included in the final review, with a total of 5821 participants. Due to the heterogeneity among the included studies, the data were presented narratively. Limited studies reported a high prevalence of EOC (19.2%–20%) and CRC (82%–100%) in individuals with TA (depending on the study) compared to those without TA (3% for EOC and 0% for CRC). While others reported a weak correlation between EOC and CRC and TA ( P > 0.05). Weak evidence suggested a strong correlation between breast, cervical uterine and prostate cancers and TA ( P < 0.05). Conclusions: Though low-quality evidence suggests a link between TA and cancer, it was not possible to verify that TA can hold a predictive value as a marker for cancers. Further research is needed to confirm the association. Registration: PROSPERO (CRD42020139751).

The establishment of the permanent dentition is a key stage in dental development. The newly erupted permanent teeth will remain with the young person for the rest of their lives. These dental changes coincide with significant changes in the rest of the young person’s life as they transition to becoming independent adults. This chapter discusses the caries risk factors of consideration for this cohort of patients and how these would help inform the clinician’s overall risk assessment. Examination of caries prevention strategies for young people deemed to be at risk and development of treatment plans for the management of dental caries in young permanent teeth are discussed, along with options for planned loss of significantly compromised first permanent molars. When and how to utilise minimally invasive techniques that maximise the preservation of dental tissues is detailed. And the chapter describes a staged approach to delivery of treatment when caring for a young person with a high caries risk.

Background Colonic motor complexes (CMCs) have been widely recorded in the large intestine of vertebrates. We have investigated whether in the smooth muscle, a single unified pattern of electrical activity, or different patterns of electrical activity give rise to the different neurogenic patterns of motility underlying CMCs in vitro. Methods To study differences of the CMCs between proximal and distal colon, we used a novel combination of techniques to simultaneously record muscle diameter and force at multiple sites along the whole mouse colon ex vivo. In addition, electrical activity of smooth muscle was recorded by suction electrodes. Key results Two distinct types of CMCs were distinguished; CMCs that propagated along the entire colon (complete CMC) and CMCs which were restricted to the proximal colon (incomplete CMC). The two types of CMC often occurred in the same preparations. Incomplete CMCs had longer bursts of smooth muscle action potentials than complete CMCs and propagated more slowly. Interestingly, both types of CMC were associated with similar frequency bursts of smooth muscle action potentials at ~2.4 Hz. In the most proximal colon, an additional firing frequency was detected close to ~7 Hz generating multiple peaks within each CMC. Conclusions & inferences We report distinct characteristics underlying complete and incomplete CMCs in isolated mouse colon. Recognizing these distinct patterns of motility will be important for future interpretation of analysis of murine colonic motility recordings. The identification of alternating patterns of motor activity in proximal colon, but not distal colon may reflect specific neural mechanisms for fecal pellet formation.

BACKGROUND Fish are increasingly being utilized as a model species for genetic manipulation studies related to gastrointestinal (GI) motility. Our aim was to identify whether patterns of GI motility in fish and the mechanisms underlying their generation are similar to those recorded from mammals (including humans). METHODS The entire intestine was removed from euthanized adult Silver Perch (n = 11) and lesioned at the midway point to obtain two equal lengths. Proximal and distal segments were studied separately in organ baths with oxygenated Krebs solution, maintained at either 15°C (n = 5) or 25°C (n = 6). Motility was analyzed during rest, after oral infusion of Krebs solution, and after application of hexamethonium (100 µM) and tetrodotoxin (TTX) (0.6 µM). KEY RESULTS Antegrade and retrograde propagating contractions (PC) were recorded in all preparations. In the proximal intestine, at 15 and 25°C, retrograde PCs occurred at 2.7 [1.7-4.5] and 3.1 [1.6-6.5] times the frequency of antegrade PCs, respectively. Colder temperatures did not inhibit PC frequency. Hexamethonium did not inhibit PC, and however, TTX abolished all contractile activity. CONCLUSIONS AND INFERENCES Both neurogenic antegrade and retrograde propagating contractions occur throughout the intestine of Silver Perch. However, unlike the mammalian colon, these motor patterns do not require enteric nicotinic transmission and they are not inhibited by cold temperatures (15°C). Therefore, while the GI motility patterns in Silver Perch resemble those recorded from the colon of mammals, there may be differences in the mechanisms that underlying their generation.

In 2016, comparisons of activity measurements of (18)F and (64)Cu using the Transfer Instrument of the International Reference System (SIRTI) took place at the National Institute of Standards and Technology (NIST, USA). This is the first SIRTI comparison for (64)Cu. Ampoules containing about 27 kBq of (18)F and 100 kBq of (64)Cu solutions were measured in the SIRTI for about 5 and 1.5 half-lives, respectively. The NIST standardized the activity in the ampoules by ionization chamber measurements traceable to 4π(LS)β−γ anticoincidence measurements. The comparisons, identifiers BIPM.RI(II)-K4.F-18 and BIPM.RI(II)-K4.Cu-64, are linked to the corresponding BIPM.RI(II)-K1.F-18 and BIPM.RI(II)-K1.Cu-64 comparisons and degrees of equivalence with the respective key comparison reference values have been evaluated. The NIST replaces its earlier degree of equivalence for (18)F obtained in the frame of the CCRI(II)-K3.F-18 comparison in 2001.

Cyclical propagating waves of muscle contraction have been recorded in isolated small intestine or colon, referred to here as motor complexes (MCs). Small intestinal and colonic MCs are neurogenic, occur at similar frequencies, and propagate orally or aborally. Whether they can be coordinated between the different gut regions is unclear. Motor behavior of whole length mouse intestines, from duodenum to terminal rectum, was recorded by intraluminal multisensor catheter. Small intestinal MCs were recorded in 27/30 preparations, and colonic MCs were recorded in all preparations ( n = 30) with similar frequencies (0.54 ± 0.03 and 0.58 ± 0.02 counts/min, respectively). MCs propagated across the ileo-colonic junction in 10/30 preparations, forming “full intestine” MCs. The cholinesterase inhibitor physostigmine increased the probability of a full intestine MC but had no significant effect on frequency, speed, or direction. Nitric oxide synthesis blockade by Nω-nitro-l-arginine, after physostigmine, increased MC frequency in small intestine only. Hyoscine-resistant MCs were recorded in the colon but not small intestine ( n = 5). All MCs were abolished by hexamethonium ( n = 18) or tetrodotoxin ( n = 2). The enteric neural mechanism required for motor complexes is present along the full length of both the small and large intestine. In some cases, colonic MCs can be initiated in the distal colon and propagate through the ileo-colonic junction, all the way to duodenum. In conclusion, the ileo-colonic junction provides functional neural continuity for propagating motor activity that originates in the small or large intestine.NEW & NOTEWORTHY Intraluminal manometric recordings revealed motor complexes can propagate antegradely or retrogradely across the ileo-colonic junction, spanning the entire small and large intestines. The fundamental enteric neural mechanism(s) underlying cyclic motor complexes exists throughout the length of the small and large intestine.

Holmium-166 is a high-energy β

Background The PICANET national average rate of unplanned extubation (UE) is 0.4 per 100 ventilator days. However, our Paediatric Intensive Care Unit is an outlier with a rate of 0.7 per 100 ventilator days in 2017. The accepted benchmark in the literature is a target of A Quality Improvement group was therefore established. A new re-taping standard operating procedure was introduced in May 2017. Aim Our aim was to identify any preventable causes of UE and define ways of reducing their incidence. Method Retrospective collection of data was undertaken. Patient details for all UE from 2014 to 2017 were entered into an Excel spreadsheet. A total of 114 patients were included. Results UE occurred most frequently in children aged Conclusions We aim to reduce UE with interventions such as COMFORT scoring, training more staff in standard re-taping practices and nurse-led extubations. Early use of enteral sedation is being considered. Nasally intubating more patients could lower our UE, but this procedure is not without risk. With only 44% of UE requiring reintubation, efforts should be made to better identify readiness for extubation. We aim to continue to assess the impact of the new re-taping standard procedure by repeating this audit cycle.

In the summer of 2017, the Système International de Référence Transfer Instrument (SIRTI) of the Bureau International des Poids et Mesures (BIPM) was hosted by the National Research Council of Canada (NRC) in Ottawa, Canada. This SIRTI visit was unique in many aspects. It was the first visit of the SIRTI to Canada. NRC was the first National Metrological Institute (NMI) to perform comparisons of four isotopes (

The management of carious primary teeth is a challenge for patients, parents and clinicians. Most evidence supporting different management strategies originates from a specialist setting and therefore its relevance to the primary care setting is questionable. The UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) has commissioned the FiCTION (Filling Children's Teeth: Indicated Or Not?) trial; a multi-centre primary dental care randomised controlled trial (RCT) to determine the most clinically and cost-effective approach to managing caries in the primary dentition in the UK. This large trial began in 2012, is due to be completed in late 2017 and involves 72 practices and 1,124 children initially aged three to seven years with dentine caries, following randomisation to one of three caries management strategies. Clinical, radiographic, quality of life, treatment acceptability and health economics data are collected during the three-year follow up period. This article provides an overview of the development and conduct of FiCTION and discusses some approaches adopted to manage challenges and achieve the patient recruitment target.

In the guinea pig distal colon, nonpropulsive neurally mediated motor patterns have been observed in different experimental conditions. Isolated segments of guinea pig distal colon were used to investigate these neural mechanisms by simultaneously recording wall motion, intraluminal pressure, and smooth muscle electrical activity in different conditions of constant distension and in response to pharmacological agents. Three distinct neurally dependent motor patterns were identified: transient neural events (TNEs), cyclic motor complexes (CMC), and distal colon migrating motor complexes (DCMMC). These could occur simultaneously and were distinguished by their electrophysiological, mechanical, and pharmacological features. TNEs occurred at irregular intervals of ~3s, with bursts of action potentials at 9 Hz. They propagated orally at 12 cm/s via assemblies of ascending cholinergic interneurons that activated final excitatory and inhibitory motor neurons, apparently without involvement of stretch-sensitive intrinsic primary afferent neurons. CMCs occurred during maintained distension and consisted of clusters of closely spaced TNEs, which fused to cause high-frequency action potential firing at 7 Hz lasting ~10 s. They generated periodic pressure peaks mediated by stretch-sensitive intrinsic primary afferent neurons and by cholinergic interneurons. DCMMCs were generated by ongoing activity in excitatory motor neurons without apparent involvement of stretch-sensitive neurons, cholinergic interneurons, or inhibitory motor neurons. In conclusion, we have identified three distinct motor patterns that can occur concurrently in the isolated guinea pig distal colon. The mechanisms underlying the generation of these neural patterns likely involve recruitment of different populations of enteric neurons with distinct temporal activation properties.

There is increasing importance placed on conducting clinical trials in dentistry to provide a robust evidence base for the treatment provided, and models of care delivered. However, providing the evidence upon which to base such decisions is not straightforward, as the conduct of these trials is complex. Currently, only limited information is available about the strategies to deliver successful clinical trials in primary care settings, and even less available on dental clinical trials. Considerable knowledge and experience is lost once a trial is completed as details about effective management of a trial are generally not reported or disseminated to trial managers and researchers. This leads to loss of vital knowledge that could assist with the effective delivery of new trials. The aim of this study is to examine the conduct and delivery of five dental clinical trials across both Australia and the UK and identify the various factors that impacted upon their implementation. Findings suggest that early stakeholder engagement, and well-designed and managed trials, lead to improved outcomes for researchers, clinic staff and patients, and increases the potential for future dissemination and translation of information into practice.

Successful aquaculture species are often chosen for their fast growth rates and fecundity, which are also characteristics of invasive species. The Pacific oyster Crassostrea gigas, which constitutes 80% of global oyster trade, has been confirmed as invasive in 17 of the 66 countries where it is cultured. The single study of its status in South Africa reported populations in six South Coast estuaries in 2001, dropping to three sites in 2003. We resurveyed these estuaries, visited others in the Eastern and Western Cape provinces, and sampled oyster tissue for molecular analyses of population structure. Pacific oysters have disappeared from Knysna and, following our collections, possibly also from the GouKou Estuary. Between 2003 and 2012, the Breede Estuary population decreased by 87%, from an estimated 184 206 to 23 760 individuals. Within this estuary, oysters 12 km upriver had denser shells and higher body condition indices than did those within 1.4 km of the river mouth, presumably reflecting higher ava...

An international key comparison, identifier CCRI(II)-K2.Ge-68, has been performed. The National Institute of Standards and Technology (NIST) served as the pilot laboratory, distributing aliquots of a

Background The contents of the guinea pig distal colon consist of multiple pellets that move anally in a coordinated manner. This row of pellets results in continued distention of the colon. In this study, we have investigated quantitatively the features of the neurally dependent colonic motor patterns that are evoked by constant distension of the full length of guinea-pig colon. Methods Constant distension was applied to the excised guinea-pig by high-resolution manometry catheters or by a series of hooks. Key Results Constant distension elicited regular Cyclic Motor Complexes (CMCs) that originated at multiple different sites along the colon and propagated in an oral or anal direction extending distances of 18.3±10.3 cm. CMCs were blocked by tetrodotoxin (TTX; 0.6 μ mol L−1), hexamethonium (100 μ mol L−1) or hyoscine (1 μ mol L−1). Application of TTX in a localized compartment or cutting the gut circumferentially disrupted the spatial continuity of CMCs. Localized smooth muscle contraction was not required for CMC propagation. Shortening the length of the preparations or disruption of circumferential pathways reduced the integrity and continuity of CMCs. Conclusions & Inferences CMCs are a distinctive neurally dependent cyclic motor pattern, that emerge with distension over long lengths of the distal colon. They do not require changes in muscle tension or contractility to entrain the neural activity underlying CMC propagation. CMCs are likely to play an important role interacting with the neuromechanical processes that time the propulsion of multiple natural pellets and may be particularly relevant in conditions of impaction or obstruction, where long segments of colon are simultaneously distended.

Double teeth present challenges for their clinical management. Recent advances in imaging, particularly cone-beam computed tomography (CBCT), have aided clinicians in accurate diagnosis and management. Data from CBCT imaging can be used for three-dimensional reconstruction to further aid pre-surgical planning. A 14-year-old Caucasian male presented with an aesthetically unacceptable double tooth in the 22 region. Clinical and radiographic examination and assessment included CBCT imaging and three-dimensional reconstruction. Based on this information, together with a comprehensive assessment of the patient’s motivation, a treatment plan consisting of extra-alveolar sectioning, re-implantation, endodontic therapy and composite resin restoration was carried out. The patient failed to return for follow-up at 6 months post-treatment. However, he did return at 12 months, where clinical and radiographic examination was undertaken. At this point the tooth was clinically sound and bony infill was seen radiographically. The information gained from the pre-surgical imaging with CBCT was useful in planning treatment in this case. However, this had to be combined with a careful assessment of the patient’s motivation to ensure that the course of treatment embarked upon was likely to be successful whilst addressing the patient’s concerns.

Background Crowns for primary molars are preformed and come in a variety of sizes and materials to be placed over decayed or developmentally defective teeth. They can be made completely of stainless steel (know as 'preformed metal crowns' or PMCs), or to give better aesthetics, may be made of stainless steel with a white veneer cover or made wholly of a white ceramic material. In most cases, teeth are trimmed for the crowns to be fitted conventionally using a local anaesthetic. However, in the case of the Hall Technique, PMCs are pushed over the tooth with no local anaesthetic, carious tissue removal or tooth preparation. Crowns are recommended for restoring primary molar teeth that have had a pulp treatment, are very decayed or are badly broken down. However, few dental practitioners use them in clinical practice. This review updates the original review published in 2007. Objectives Primary objective To evaluate the clinical effectiveness and safety of all types of preformed crowns for restoring primary teeth compared with conventional filling materials (such as amalgam, composite, glass ionomer, resin modified glass ionomer and compomers), other types of crowns or methods of crown placement, non-restorative caries treatment or no treatment. Secondary objective To explore whether the extent of decay has an effect on the clinical outcome of primary teeth restored with all types of preformed crowns compared with those restored with conventional filling materials. Search methods We searched the following electronic databases: Cochrane Oral Health Group Trials Register (to 21 January 2015), Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library, 2014, Issue 12), MEDLINE via Ovid (1946 to 21 January 2015) and EMBASE via Ovid (1980 to 21 January 2015). We searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials and Open Grey for grey literature (to 21 January 2015). No restrictions were placed on the language or date of publication when searching the databases. Selection criteria Randomised controlled trials (RCTs) that assessed the effectiveness of crowns compared with fillings, other types of crowns, non-restorative approaches or no treatment in children with untreated tooth decay in one or more primary molar teeth. We would also have included trials comparing different methods of fitting crowns. For trials to be considered for this review, the success or failure of the interventions and other clinical outcomes had to be reported at least six months after intervention (with the exception of 'pain/discomfort during treatment and immediately postoperatively'). Data collection and analysis Two review authors independently assessed the title and abstracts for each article from the search results. and independently assessed the full text for each potentially relevant study. At least two authors assessed risk of bias and extracted data using a piloted data extraction form. Main results We included five studies that evaluated three comparisons. Four studies compared crowns with fillings; two of them compared conventional PMCs with open sandwich restorations, and two compared PMCs fitted using the Hall Technique with fillings. One of these studies included a third arm, which allowed the comparison of PMCs (fitted using the Hall Technique) versus non-restorative caries treatment. In the two studies using crowns fitted using the conventional method, all teeth had undergone pulpotomy prior to the crown being placed. The final study compared two different types of crowns: PMCs versus aesthetic stainless steel crowns with white veneers. No RCT evidence was found that compared different methods of fitting preformed metal crowns (i.e. Hall Technique versus conventional technique). We considered outcomes reported at the dental appointment or within 24 hours of it, and in the short term (less than 12 months) or long term (12 months or more). Some of our outcomes of interest were not measured in the studies: time to restoration failure or retreatment, patient satisfaction and costs. Crowns versus fillings All studies in this comparison used PMCs. One study reported outcomes in the short term and found no reports of major failure or pain in either group. There was moderate quality evidence that the risk of major failure was lower in the crowns group in the long term (risk ratio (RR) 0.18, 95% confidence interval (CI) 0.06 to 0.56; 346 teeth in three studies, one conventional and two using Hall Technique). Similarly, there was moderate quality evidence that the risk of pain was lower in the long term for the crown group (RR 0.15, 95% CI 0.04 to 0.67; 312 teeth in two studies). Discomfort associated with the procedure was lower for crowns fitted using the Hall Technique than for fillings (RR 0.56, 95% CI 0.36 to 0.87; 381 teeth) (moderate quality evidence). It is uncertain whether there is a clinically important difference in the risk of gingival bleeding when using crowns rather than fillings, either in the short term (RR 1.69, 95% CI 0.61 to 4.66; 226 teeth) or long term (RR 1.74, 95% CI 0.99 to 3.06; 195 teeth, two studies using PMCs with conventional technique at 12 months) (low quality evidence). Crowns versus non-restorative caries treatment Only one study compared PMCs (fitted with the Hall Technique) with non-restorative caries treatment; the evidence quality was very low and we are therefore we are uncertain about the estimates. Metal crowns versus aesthetic crowns One split-mouth study (11 participants) compared PMCs versus aesthetic crowns (stainless steel with white veneers). It provided very low quality evidence so no conclusions could be drawn. Authors' conclusions Crowns placed on primary molar teeth with carious lesions, or following pulp treatment, are likely to reduce the risk of major failure or pain in the long term compared to fillings. Crowns fitted using the Hall Technique may reduce discomfort at the time of treatment compared to fillings. The amount and quality of evidence for crowns compared to non-restorative caries, and for metal compared with aesthetic crowns, is very low. There are no RCTs comparing crowns fitted conventionally versus using the Hall Technique.

We report herein a nymphal Amblyomma dissimile Koch, 1844 (Acari: Ixodidae) parasitizing an adult Rhinella margaritifera (Anura: Bufonidae) in lowland tropical rainforest in French Guiana. This is the first report of a tick parasitizing R. margaritifera.

Autotransplantation of immature teeth has good survival rates, and has benefits over ossointegrated implants in the growing child, but is very technique sensitive. Spiral CT imaging has been previously used in adult patients to enable computer-aided prototyping to produce a surgical template of the donor tooth, further increasing success rates. Case report: The case presented describes management of a 9-year-old girl with the combination of hypodontia affecting the upper lateral incisors as well as a severely ectopic maxillary canine. Cone beam CT was used in combination with computer-aided prototyping to produce a surgical template of an immature mandibular second premolar. The surgical template was used to prepare the transplant site before the donor tooth was extracted, greatly reducing the time from extraction to implantation. By 6 months posttransplant the tooth was clinically sound, and continued root development and laying down of dentine was visible radiographically. Discussion: This paper demonstrates the use of a novel technique to aid the surgical procedure of autotransplantation of immature premolar teeth. The use of autotransplantation in this case allowed the difficult situation of two missing units in the upper left quadrant to be reduced to one unit, while retaining symmetry in the upper arch. Compared to previous studies, the use of cone beam CT to create a 3D prototype reduced radiation dose compared to spiral CT and drastically reduced the extra-oral time of the donor tooth from extraction to transplantation.

Purpose There are many hypotheses accounting for detrusor overactivity; however, the exact mechanisms are still incompletely understood. We used a model of bladder outlet obstruction in male guinea pigs as a way to produce detrusor overactivity. The objective was to determine whether changes in voiding of obstructed guinea pigs correlates with specific changes in contractile activity of their isolated bladders in vitro. Material and methods Conscious voiding activity of sham-operated and obstructed animals was measured in metabolic cages. Contractile activity (spontaneous or evoked by distension, electrical field stimulation or cholinergic agonists) was recorded via a pressure transducer in the isolated bladders in vitro. Results The frequency of conscious voiding increased (while voiding volume decreased) in the obstructed group, compared with the sham-operated group, 4 weeks after surgical intervention. In comparison to the sham-operated animals, the bladders from the obstructed guinea pigs were enlarged and inflamed, their frequency of spontaneous contractions was higher, while the amplitudes of electrical field stimulation (EFS)-induced contractions and bladder compliance were lower. Changes in conscious voiding during obstruction were significantly associated with alterations in structural parameters (bladder weight, thickness and histological damage score) and functional contractile parameters (frequency of spontaneous contractions, amplitude of EFS-induced contractions and bladder compliance) of their isolated bladders. Conclusions Our findings revealed significant association between conscious voiding and structural and contractile activity changes of the isolated bladders in obstruction. The data suggest that change in contractile activity of the bladder itself is a major contributor to obstruction-induced bladder overactivity.

A two year placebo-controlled, double-blind, randomised control trial in 1-4-year-old children.Children were recruited from low income families in Rio de Janeiro, Brazil, with access to a fluoridated public water supply. Both groups received oral hygiene instruction along with provision of toothbrushes and 1450 ppm F- toothpaste. The control group had a placebo fluoride varnish applied every six months. The intervention group had 22,600 ppm F- varnish applied every six months. Clinical examinations for the presence of caries were conducted at baseline and at each subsequent six monthly visit.The primary outcome was the proportion of children in each group that went on to clinically develop any new carious surfaces using the ICDAS criteria. The number of new carious surfaces was assessed as a secondary outcome, both at the enamel and dentine level. The study also reported on the safety and acceptability of the varnish.Two hundred children participated in the trial, 91% were followed up at two years and adherence to the six-monthly applications was 84% in the intervention and 85% in control groups. The results did not show a significant difference for the development of new lesions between the two groups. In the fluoride varnish group 36% had developed new dentinal lesions compared to 47% in the placebo group, a difference of -10.8% (95% CI -24.9 to 3.3, p = 0.14). In relation to caries increment, at the enamel level, this was a mean of 2.0 teeth in the fluoride varnish group and 2.8 teeth in the placebo group, a difference of -0.8 (95% CI -2.0 to 0.4, p = 0.19). At the dentine level, caries increment was a mean of 1.8 teeth in the fluoride varnish group and 2.5 in the placebo group, a difference of -0.7 (95% CI -1.9 to 0.4, p = 0.23). Two minor complaints related to taste and appearance of the varnish were recorded and no safety events were reported.Whilst no significant difference was found, the authors note that this does not indicate ineffectiveness of fluoride varnish. Re-assessment of the power calculation following study completion demonstrated that a significantly larger sample size would have been indicated, preventing the drawing of any direct conclusions from the results of this study. The use of fluoride varnish amongst this group appears to be safe and overall well tolerated.

International measurement comparisons are organised regularly for EU laboratories involved in monitoring radioactivity, with emphasis on meeting routine measurement conditions. Using the recent comparison of 137Cs in air filters as an example, the whole cycle is described: establishment of traceable reference values, spiking of individual filters for the comparison and their quality assurance, treatment and measurement of filters in the participating laboratories and evaluation of comparison results. The treatment of an individual result, deviating widely from the reference value, is discussed. Monte-Carlo simulations allow to estimate the maximum errors possibly made due to a non-suitable measurement geometry.

This study investigated what influences mental health professionals when deciding whether or not to tell someone with dementia their diagnosis. A qualitative methodology was employed and the data analysed using grounded theory. Currently people with dementia tend not to be told their diagnosis, despite evidence that sharing diagnostic information can improve psychological well-being and adjustment. Why professionals are reluctant to share diagnostic information with people with dementia is unclear, although the literature raises a number of possibilities. Seven professionals were interviewed (two clinical psychologists and five community psychiatric nurses). The main influence on their disclosure practice was uncertainty about whether the person with dementia would want to know the diagnosis, fueled by a fear that to tell them if they did not want to know would cause harm. Professionals also expressed a strong sense of both hopelessness and helplessness when confronted with dementia. This was then projected onto the person with dementia, which in turn led to the professionals adopting an overly protective stance towards them. If professionals are to resolve their sense of uncertainty about what the person with dementia wants, in terms of diagnostic information, services need to develop ways in which the views of people with dementia can be heard and start to influence service provision and policy.

Objective To identify reasons behind a lower than expected participant recruitment rate within the FiCTION trial, a multi-centre paediatric primary dental care randomised controlled trial (RCT). Subjects (materials) and methods An online survey, based on a previously published tool, consisting of both quantitative and qualitative responses, completed by staff in dental practices recruiting to FiCTION. Ratings from quantitative responses were aggregated to give overall scores for factors related to participant recruitment. Qualitative responses were independently grouped into themes. Results Thirty-nine anonymous responses were received. Main facilitators related to the support received from the central research team and importance of the research question. The main barriers related to low child eligibility rates and the integration of trial processes within routine workloads. Conclusions These findings have directed strategies for enhancing participant recruitment at existing practices and informed recruitment of further practices. The results help provide a profile of the features required of practices to successfully screen and recruit participants. Future trials in this setting should consider the level of interest in the research question within practices, and ensure trial processes are as streamlined as possible. Research teams should actively support practices with participant recruitment and maintain enthusiasm among the entire practice team.

PURPOSE/BACKGROUND: Following laser panretinal photocoagulation (PRP) for proliferative diabetic retinopathy, patients are at risk of failing the UK driving visual field test due to loss of peripheral field. Although a definition of the minimum field requirement exists, differences in its interpretation may influence whether fields pass or fail. Currently it is not known how fields are interpreted in practice nor to what extent this affects failure rates. METHODS: Uniocular and binocular Esterman visual fields from 60 diabetic patients following PRP were examined both by the chairman of the Visual Standards Sub-Committee of the Royal College of Ophthalmologists and separately by four consultant ophthalmologists. The results were analysed (1) to assess the extent of agreement and (2) to identify, from the chairman's results, the field deficits that are still compatible with passing. RESULTS: Agreement was generally good for binocular fields but was only moderate for uniocular fields. In up to 15% of binocular fields and 43% of uniocular fields the chairman's decision was different from that of the consultants. Several key aspects of the field that influence a pass/fail decision are identified. CONCLUSIONS: Substantial differences in the assessment of driving visual fields following RPR currently exist between consultants and the chairman of the Visual Standards Sub-Committee. Using the information presented here to guide assessment it is now possible to reduce this variation.

Although laser panretinal photocoagulation (PRP) for proliferative diabetic retinopathy is known to cause peripheral field constriction, the risks of failing the UK driving field test following treatment are currently unclear as the small number of previous studies have conflicting results. Following PRP using only argon laser with a 500 microns spot size, both uniocular and binocular Esterman visual fields from 60 diabetic patients were assessed by the Chairman of the Visual Standards Sub-Committee of the Royal College of Ophthalmologists. Forty-two per cent of uniocular fields from treated eyes failed. Twelve per cent of binocular fields from those having bilateral PRP failed. Type II diabetes was associated with a significant increase in the risk of failure. Although there is a high risk of failure in any given treated eye, 88% of diabetics will pass a binocular field test, even if both eyes are treated.

Objective To evaluate the impact of a continuous improvement project to improve completion of a caries risk assessment (CRA) and to assess its impact on delivery of dental caries prevention. Design Single centre clinical improvement project. Setting A paediatric dental department within a UK dental hospital over the course of 2008-2009. Subjects (materials) and methods Continuous monitoring of documentation of a CRA was instigated and results fed back to clinicians. Tools were developed to structure the process of CRA. After six months of intervention, a comparison of preventive care to a pre-intervention sample was undertaken. Main outcome measures The main outcome measure was completion of a CRA. Comparison was also made with pre-intervention data on levels of preventive care received. Results Over the 12 month project the mean rate of CRA completion improved from 30% over the first 6 months to 73% in the second 6 months. Compared to the pre-intervention sample, all items of the caries prevention package had improved, with delivery of toothpaste strength advice (16% vs 60%, p = 0.001) and diet advice (32% vs 70%, p = 0.004) improving significantly. Conclusion By targeting and improving CRA completion the quality of preventive care delivered has also significantly improved.

A retrospective survey was carried out of serious eye injury caused by windscreen contact in road traffic accidents over a 6–year period. All 15 patients had contacted toughened windscreens, and all but one did not wear seat belts. The cost in terms of pounds sterling paid out by the National Health Service, and also the cost in terms of visual handicap were assessed. It was found that of the 15 patients admitted during this time, the treatment of the large majority cost at least twice as much as that for patients undergoing routine cataract surgery. This was primarily due to the longer hospitalization necessary. Only 2 patients retained a visual acuity of 6/6.

Twenty-six patients with primary or secondary Sjögren's syndrome were treated in a double-blind, cross-over trial for a four week period with oral N-Acetylcysteine and placebo. Before treatment there were significantly elevated salivary lactoferrin levels in the patients when compared to 51 healthy controls (p = 0.0005), and significantly decreased levels of tear lysozyme when compared to 24 controls (p = 0.0003). Salivary sodium, potassium, inorganic phosphate, amylase and immunoglobulin G, A or M levels were not significantly different from control values. After treatment with N-Acetylcysteine, Sjögren's syndrome patients reported improvements in ocular soreness (p = 0.004), ocular irritability (p = 0.006), halitosis (p = 0.033) and daytime thirst (p = 0.033). N-Acetylcysteine, but not placebo improved the van Bijsterveld score (p = 0.026), but neither agent improved the Schirmer test, the tear break up time or any of the laboratory tests. These results suggest that N-Acetylcysteine may have a true therapeutic effect on the ocular symptoms of Sjögren's syndrome and be worthy of a longer study.

Forty-six eyes with chronic open-angle glaucoma (COAG) and 24 eyes which had previously undergone trabeculectomy for COAG were studied and the postural response of the intraocular pressure compared with that of 70 normal eyes. In all three groups the greatest rise in intraocular pressure (IOP) occurred when the subject changed from the sitting to the lying position. In the control group this was never more than 2 mmHg in any subject. The rise was greater than 2 mmHg in 93% of the patients suffering from COAG who were treated medically and in 100% of the eyes of those on which trabeculectomy had been performed. The well recognised abnormal postural response of intraocular pressure in COAG appears both to be retained and to be unaffected in those eyes which have undergone trabeculectomy.

A video system to monitor continuous Gold laser photoradiation treatment of an ocular melanoma is described. We believe this technique considerably improves the safety and accuracy of continuous laser treatment.

Forty-five patients with poorly controlled chronic open angle glaucoma underwent pneumotonography immediately prior to argon laser trabeculoplasty. The coefficient of facility of outflow (c-value) was calculated from the pneumotonography and correlated with the intraocular pressure rise one hour after the argon laser trabeculoplasty. It appeared that there was a strong relationship between a low c-value indicating a poor outflow facility and a large intraocular pressure rise following argon laser trabeculoplasty. The implications of being able to predict the intraocular pressure rise after argon laser trabeculoplasty are discussed.

This narrative review aims to highlight sources of the best available evidence and describe primary clinical trials currently taking place in primary dental care across the United Kingdom which will add to the evidence base. Clinical Relevance: To provide evidence-based dental care, dental professionals have to integrate the best available evidence, their clinical experience and their patients' values; this paper should help to identify user-friendly sources of the best available evidence.

A video system to monitor continuous Gold laser photoradiation treatment of an ocular melanoma is described. We believe this technique considerably improves the safety and accuracy of continuous laser treatment.