Abstracts of the 24th international isotope society (UK group) symposium: synthesis and applications of labelled compounds 2015.

The 24th annual symposium of the International Isotope Society's United Kingdom Group took place at the Møller Centre, Churchill College, Cambridge, UK on Friday 6th November 2015. The meeting was attended by 77 delegates from academia and industry, the life sciences, chemical, radiochemical and scientific instrument suppliers. Delegates were welcomed by Dr Ken Lawrie (GlaxoSmithKline, UK, chair of the IIS UK group). The subsequent scientific programme consisted of oral presentations, short 'flash' presentations in association with particular posters and poster presentations. The scientific areas covered included isotopic synthesis, regulatory issues, applications of labelled compounds in imaging, isotopic separation and novel chemistry with potential implications for isotopic synthesis. Both short-lived and long-lived isotopes were represented, as were stable isotopes. The symposium was divided into a morning session chaired by Dr Rebekka Hueting (University of Oxford, UK) and afternoon sessions chaired by Dr Sofia Pascu (University of Bath, UK) and by Dr Alan Dowling (Syngenta, UK). The UK meeting concluded with remarks from Dr Ken Lawrie (GlaxoSmithKline, UK).

Practically convenient and industrially-aligned methods for iridium-catalysed hydrogen isotope exchange processes.

The use of alternative solvents in the iridium-catalysed hydrogen isotope exchange reaction with developing phosphine/NHC Ir(I) complexes has identified reaction media which are more widely applicable and industrially acceptable than the commonly employed chlorinated solvent, dichloromethane. Deuterium incorporation into a variety of substrates has proceeded to deliver high levels of labelling (and regioselectivity) in the presence of low catalyst loadings and over short reaction times. The preparative outputs have been complemented by DFT studies to explore ligand orientation, as well as solvent and substrate binding energies within the catalyst system.

Formal total synthesis of (+/-)-alpha- and beta-cedrene by preparation of cedrone. Construction of the tricyclic carbon skeleton by the use of a highly efficient intramolecular Khand annulation.

The cedrene carbon skeleton was rapidly assembled from a simple monocyclic precursor by the strategic use of a high yielding intramolecular Khand cyclization reaction. Further synthetic manipulations provided a concise formal total synthesis of alpha- and beta-cedrene. Reaction: see text.

Enantioselective deprotonation reactions using polymer-supported chiral magnesium amide bases.

Novel and readily accessible polymer-supported chiral magnesium amide reagents have been prepared and shown to be effective in the asymmetric deprotonation of a series of prochiral cyclohexanones, affording good to excellent levels of both conversion and enantiomeric ratio (up to 93:7); the Merrifield-based chiral amine species has been shown to be readily recyclable.

The areas of various surfaces in the human mouth from nine years to adulthood.

Surface area measurements of five regions of the oral cavity were made from study casts of 57 subjects with an age range from 9.3 to 19 years. While the longitudinal pattern of growth exhibited by the total of the five areas, when subgroups were compared, was characterized by a steady increase to around puberty (13 years), followed by a plateau, different areas showed different patterns of growth. Increase in the surface area of the teeth was associated with the eruption of the second and third molars, whereas the area of the buccal lingual mucosa continued to increase into adult life. The palate, buccal vestibular mucosa, and dorsum of the tongue demonstrated a typically skeletal pattern of growth, i.e., increase until puberty with a rapid cessation thereafter. The results of this study indicate the need for longitudinal data to further knowledge concerning growth of the oral cavity.

The general dental status of patients referred to the orthodontic department of the Glasgow Dental Hospital.

A survey of 280 orthodontic referrals to the Glasgow Dental Hospital, consecutively screened for orthodontic needs, revealed that 1 in 5 had untreated caries and more than half had a level of oral hygiene incompatible with wearing an orthodontic appliance. The suitability and motivation of such patients, therefore, must be questioned before prescribing orthodontic treatment.

The first orthodontic diploma.

The advent of the Inter-Collegiate Membership in Orthodontics in the year 2000 will mark the end of an orthodontic diploma specific to the Royal College of Physicians and Surgeons of Glasgow. The Diploma in Dental Orthopaedics (RCPS) was the first orthodontic diploma in the United Kingdom. The fact that such a diploma has existed first as a DDO and latterly as the MDO (Membership) for some 50 years is remarkable in view of the relative infancy of most dental specialties and the fact that the General Dental Council has instigated a specialist register in orthodontics as recently as 1998. It was 1965, before other specialty diplomas became available in the British Isles, with the introduction of the FFD by the Royal College of Surgeons in Ireland.

The use of removable orthodontic appliances in the General Dental Service.

One hundred and fifty removable appliance cases consecutively sampled by the Scottish Dental Practice Board were analysed using the PAR index. The cases were assessed as being suited or unsuited to the removable appliance approach based on the presenting features previously shown to be effectively treated by removable appliances. Using chi-squared tests of association, suitable cases were characterised as being in the mixed dentition, had one feature treated and one appliance used. Suitable cases on average showed 3-4 PAR points more improvement as a result of treatment than equivalent unsuitable cases; regression equations are given. Because of the wide variability within the sample it proved impossible to predict accurately the expected duration of treatment in the General Dental Service.

CASES--clinical audit; scenarios for evaluation and study.

CASES, an audit and continuing education programme, evaluated aspects of current orthodontic practice and allowed orthodontists to identify areas where their practice differed from regional and national results. Evaluation of the CASES programme verified its value in audit and continuing education and the authors hope it will encourage similar projects in other disciplines too.

Light-curing acrylic resin as an orthodontic baseplate material.

Heat-curing autopolymerizing (self-cure or cold-cure), thermoplastic, and light-curing acrylic resin are the most commonly used orthodontic baseplate materials. While cured acrylic resins present few problems to the patient, in the laboratory acrylic resin has to be sprayed, mixed, or packed in a fume-extraction unit because of the harmful fumes emitted by the raw inflammable chemicals. Light-curing material, on the other hand, is virtually nonflammable and has virtually no aroma. A light-cure technique for the construction of orthodontic baseplates is described. While buildup of the baseplate is slightly slower than for self-cured material, the shorter time involved in trimming and polishing means that overall construction is faster. It is easier to obtain a uniform thickness with light-cured material, and it provides superior fit. These results, however, are subject to more extensive clinical trials. The only apparent disadvantage is the fine powder produced during trimming. Even with a bench equipped with an extraction unit, it is advisable to use a face mask to prevent the inhalation of dust.

The nasopharynx, face height, and overbite.

In lateral cephalometric films of a group of male subjects, none of whom was a mouth breather, the statistical relationships between overbite and nasopharyngeal dimensions were weak. Moderate relationships were found between face height and nasopharyngeal dimensions. Strongest correlations, with a peak at 10 years, were between--Face height and nasopharyngeal height (+) Face height and nasopharyngeal area (+) Face height and roof angle (-) Dynamic correlations between overbite, face height and nasopharyngeal dimensions were weak. Class II malocclusion subjects on average showed--Smaller Nasopharyngeal and Adenoid Areas. Larger Airways in both real and proportional terms, compared with Class I and normal occlusion subjects.

The variability of some craniofacial dimensions.

The variability of eight linear and five angular dimensions measured on 124 lateral skull radiographs of 10-year-old boys was assessed by means of Bartlett's test for homogeneity of variances and Pitman's test for the comparison of correlated standard deviations. The linear dimensions which demonstrated the greatest variability within the four constituent Angle classes (N = 31) were mandibular body length, total cranial base length, total mandibular length and lower face height. The dimensions which demonstrated the least intra-group but greatest inter-group variability were maxillary length and Angle SNB. The Class II division 2 group exhibited the greatest variation in skeletal morphology; it is therefore postulated that its etiology is mainly dentoalveolar and soft tissue in origin.

Mandibular form and position related to changed mode of breathing--a five-year longitudinal study.

A five-year follow-up study was performed on 26 children treated for nasal obstruction by adenoidectomy, who exhibited a changed mode of breathing postoperatively. They were compared with a control group matched according to age and sex. Lateral skull radiographs were used to examine mandibular morphology. The mandibular outline was registered using 36 digitized points. This method of portraying growth changes provides a valuable complement to isolated measurements. The technique revealed a more anterior direction of symphyseal growth in the adenoidectomy group following surgery as well as some reversal of the initial tendency to a posterior rotation of the mandible.

Surgery, growth modification or orthodontic camouflage? Brian's case.

A skeletal class II malocclusion can be dealt with in a number of ways. The preferred option is to use orthodontic treatment and growth modification if at all possible, but in cases where this is not possible the problem might be camouflaged or treated by surgery. In the case reported here the options are fully discussed and the opinions of the orthodontists expressed in the CASES project made clear. The actual treatment undertaken is also described.

How to do it: making audit work.

The orthodontic Audit Working Party of the Faculty of Dental Surgery, Royal College of Surgeons of England, in collaboration with the Centre for Medical Education, Ninewells Hospital and Medical School, Dundee developed an audit project entitled 'Clinical Audit: Scenarios for Evaluation and Study'. The aim of the project was to contribute to the construction of clinical guidelines for orthodontists. This article, the first of a short series, describes the background to and general results of the study. Further articles will study individual aspects of the project.

Early treatment of Class III malocclusion? Colin's case.

This is the first of six simulated case reports accompanying the questionnaire detailed in the article 'How to Do It: Making Clinical Audit Work' found earlier in this issue. You will find comprehensive discussion of the problem of making a decision about the early treatment of Class III malocclusion.

An extraction dilemma: Cheryl's case.

This article describes treatment options for a teenager with a mild, although aesthetically unpleasing, malocclusion. The opinions of British orthodontists, as obtained through the CASES project, are summarized and the patient's actual treatment is discussed.

Hypodontia: George's case.

Five questions are posed regarding the treatment of a patient with hypodontia. The treatment options are discussed, and the actual treatment carried out demonstrated. The treatment preferences of British Orthodontists, elicited through the CASES project, are also included.

An adult with a severe Class II division 1 malocclusion: Frances' case.

This article describes treatment options for an adult with a severe Class II division 1 malocclusion. The opinions of British orthodontists, as obtained through the CASES project, are summarized and the patient's actual treatment is discussed.

An adolescent with a Class II division 2 malocclusion complicated by unerupted palatal canines: Linda's case.

This article describes treatment options for a teenager with a class II division 2 malocclusion complicated by unerupted and palatally displaced upper canines. The opinions of British orthodontists, as obtained through the CASES project, are summarized and the patient's actual treatment is discussed.