University Dental Hospital on Cardiff University

OBJECTIVES: To better understand reasons for antibiotics being prescribed for sore throats despite well known evidence that they are generally of little help. DESIGN: Qualitative study with semi-structured interviews. SETTING: General practices in South Wales. SUBJECTS: 21 general practitioners and 17 of their patients who had recently consulted for a sore throat or upper respiratory tract infection. MAIN OUTCOME MEASURES: Subjects' experience of management of the illness, patients' expectations, beliefs about antibiotic treatment for sore throats, and ideas for reducing prescribing. RESULTS: Doctors knew of the evidence for marginal effectiveness yet often prescribed for good relationships with patients. Possible patient benefit outweighed theoretical community risk from resistant bacteria. Most doctors found prescribing "against the evidence" uncomfortable and realised this probably increased workload. Explanations of the distinction between virus and bacterium often led to perceived confusion. Clinicians were divided on the value of leaflets and national campaigns, but several favoured patient empowerment for self care by other members of the primary care team. Patient expectations were seldom made explicit, and many were not met. A third of patients had a clear expectation for antibiotics, and mothers were more likely to accept non-antibiotic treatment for their children than for themselves. Satisfaction was not necessarily related to receiving antibiotics, with many seeking reassurance, further information, and pain relief. CONCLUSIONS: This prescribing decision is greatly influenced by considerations of the doctor-patient relationship. Consulting strategies that make patient expectations explicit without damaging relationships might reduce unwanted antibiotics. Repeating evidence for lack of effectiveness is unlikely to change doctors' prescribing, but information about risk to individual patients might. Emphasising positive aspects of non-antibiotic treatment and lack of efficacy in general might be helpful.

During routine school dental inspections 100 boys and 100 girls were interviewed. Various characteristics of each child and his subjective feelings about his dental appearance and need for orthodontic treatment were recorded. The accuracy with which each child perceived his dental appearance was assessed from his ability to describe various anterior occlusal features and to identify a colour photograph of his own teeth. A similar procedure was conducted with the mothers of 50 of the children. Finally, an objective assessment of the degree of visible occlusal irregularity was made. Analysis of the data indicates that dissatisfaction with dental appearance was commoner among girls and associated with increasing age (over the short range studied), dental attendance pattern and the experience of teasing, but not with intelligence or social class. The majority of children and parents failed to describe the child's anterior occlusal characteristics accurately and almost one third of children and parents failed to identify the child's dental photograph. It was not however possible to find an association with any of the recorded characteristics of the child and the accuracy of occlusal self perception. Although the most important determinant of satisfaction with dental appearance and desire for orthodontic treatment was the degree of visible occlusal irregularity, many children with moderate to severe irregularities were satisfied with their dental appearance while others with minor irregularities, or none at all, were dissatisfied. Possible reasons for this are discussed.

The PCR was used to amplify a targeted region of the ribosomal DNA from 84 Candida isolates. Unique product sizes were obtained for Candida guilliermondii, Candida (Torulopsis) glabrata, and Candida pseudotropicalis. Isolates of Candida albicans, Candida tropicalis, Candida stellatoidea, Candida parapsilosis, and Candida krusei could be identified following restriction digestion of the PCR products.

This work was part of a long-term research project undertaken by the Medical Applications Group of PDR into the application of advanced design techniques to the needs of the dental technology industry, in particular the design and manufacture of Removable Partial Denture Frameworks (RPDs). \n \nThese frameworks are traditionally made in wax by hand in a highly-skilled, laborious and time consuming process. Previous research carried out by MAG had established that advanced design techniques including three-dimensional scanning and computer-aided design (CAD) could be used to develop accurate designs for custom-fitting RPD devices (see Williams outputs). This research suggested that digital processes could yield benefits in productivity and repeatability. However, the multiple steps required to produce sacrificial patterns and castings did not fully exploit the potential advantages of computer-aided manufacture. \n \nThis article reported on the exploitation of a new layer-additive manufacturing technique called Selective Laser Melting (SLM). SLM manufactures metal parts of almost any shape directly from computer designs. This research required experimentation to establish design parameters for the successful manufacture of RPD frameworks using SLM, including design considerations, build strategies, optimum orientation and support generation. Assessment of the RPD frameworks produced by SLM in both Cobalt-Chrome alloy and 316L Stainless Steel demonstrated that the finished items were fit for purpose and compared favourably to frameworks made by traditional techniques. Subsequent research has demonstrated that the devices produced fit patients as required and further work is being undertaken to enable commercial and technical benefits to be realised (see Williams output 4). \n \nThis work reports the world’s first successful production of an RPD framework using a computer-aided design and direct layer-additive manufacturing process.

AIMS: To establish whether irrigant activation techniques (IATs) result in greater intracanal smear layer and debris removal than conventional needle irrigation (CNI). METHODOLOGY: Six electronic databases were searched to identify scanning electron microscopy studies evaluating smear layer and/or debris removal following the use of manual dynamic activation (MDA), passive ultrasonic irrigation (PUI), sonic irrigation (SI) or apical negative pressure (ANP) IATs in mature permanent teeth. Meta-analyses were performed for each canal segment (coronal, middle, apical and apical 1 mm) in addition to subgroup analyses for individual IATs with respect to CNI. Outcomes were presented as standardized mean differences (SMD) alongside 95% confidence intervals (95% CI) and chi-squared analysis. RESULTS: From 252 citations, 16 studies were identified. The meta-analyses demonstrated significant improvements in coronal (SMD: 1.15, 95% CI: 0.72-1.57 / SMD: 0.54, 95% CI: 0.29-0.80), middle (SMD: 1.30, 95% CI: 0.59-2.53 / SMD: 0.8, 95% CI: 0.58-1.13) and apical thirds (SMD: 1.22, 95% CI: 0.83-1.62 / SMD: 1.86, 95% CI: 0.76-2.96) for smear layer and debris removal, respectively. In the apical 1 mm IATs improved cleanliness; however, differences were insignificant (SMD: 1.15, 95% CI: -0.47-2.77). Chi-squared analysis revealed heterogeneity scores of 79.3-92.8% and 0.0-93.5% for smear layer and debris removal, respectively. CONCLUSIONS: IATs improve intracanal cleanliness across a substantial portion of the canal, and therefore, their use is recommended throughout root canal preparation. However, current data is too heterogeneous to compare and identify superiority of an individual technique highlighting the need to standardize experimental protocols and develop a more representative research model to investigate the in vivo impact of IATs on clinical outcomes and periapical healing following root canal treatment.

The accurate modelling of teeth under orthodontic load in the laboratory has many shortcomings in that it has not been possible to integrate methods, such as three-dimensional models, photo-elastic stress analysis, laser holographic interferometry, and animal studies, to give comprehensive and repeatable results. In this study, using a three-dimensional finite element model of a human maxillary canine tooth, the maximum principal stresses in the periodontal ligament produced by various orthodontic forces were determined. 1 Newton tipping forces produced stresses at the cervical margin of the periodontal ligament as high as 0.196 N/mm2 and apical stresses up to -0.034 N/mm2, while rotatory forces of two equal, but opposing forces of 0.5 Newton at the cervical margin of the crown produced cervical margin stresses ranging between -0.035 and 0.051 N/mm2, and apical stresses of between 0.0018 and 0.0027 N/mm2. These stresses are examined and discussed in relation to previous clinical, laboratory, and histological studies.

Dentine hypersensitivity occurs when dentinal tubules are open on the dentine surface and patent to a vital pulp. There has been limited interest in the aetiology of dentine hypersensitivity. In particular, little is known about agents that remove the dentine smear layer to expose tubules. Toothbrushing certainly may expose dentine, but whether a toothbrush per se has the effect of opening tubules has not been established. The aim of this study in vitro was to determine whether a toothbrush could remove or create a smear layer. In addition, the combined effects of toothbrushing with dietary fluids on dentine was assessed. Toothbrushing was observed, by scanning electron microscopy, both to remove and to recreate a smear layer on dentine specimens. However, the processes took a considerable time, and under conditions of normal toothbrushing it is unlikely that the latter plays a direct aetiological role in opening tubules. Indeed, together with toothpaste it is more likely that brushing has a therapeutic action by mechanically forming a smear layer. Conversely, and importantly, toothbrushing in the presence of dietary acids enhanced smear layer removal. This finding raises the question of whether the dental profession should be advising that teeth be brushed before meals rather than after, as is often the case.

INTRODUCTION: A torn labial frenum is widely regarded as pathognomonic of abuse. METHODS: We systematically reviewed the evidence for this, and to define other intra-oral injuries found in physical abuse. Nine studies documented abusive torn labial frena in 27 children and 24 [corrected] were fatally abused: 22 were less than 5 years old. Only a direct blow to the face was substantiated as a mechanism of injury. RESULTS: Two studies noted accidentally torn labial frena, both from intubation. Abusive intra-oral injuries were widely distributed to the lips, gums, tongue and palate and included fractures, intrusion and extraction of the dentition, bites and contusions. CONCLUSIONS: Current literature does not support the diagnosis of abuse based on a torn labial frenum in isolation. The intra-oral hard and soft tissue should be examined in all suspected abuse cases, and a dental opinion sought where abnormalities are found.

OBJECTIVES: As part of an ongoing programme to improve diagnosis and treatment planning relevant to implant placement, orthodontic treatment and dentomaxillofacial surgery, a study has been made of the spatial accuracy and density response of an i-CAT, a cone beam CT (CBCT) dental imaging system supplied by Imaging Sciences International Inc. METHODS: Custom-made phantoms using acrylic sheet and water were used for measurements on spatial accuracy, density response and noise. The measurements were made over a period of several months on a clinical machine rather than on a machine dedicated to research. RESULTS: Measurements on a precision grid showed the spatial accuracy to be universally within the tolerance of +/-1 pixel. The density response and the noise in the data were found to depend strongly on the mass in the slice being scanned. CONCLUSIONS: The density response was subject to two effects. The first effect changes the whole slice uniformly and linearly depends on the total mass in the slice. The second effect exists when there is mass outside the field of view, dubbed the "exo-mass" effect. This effect lowers the measured CT number rapidly at the scan edge furthest from the exo-mass and raises it on the adjacent edge. The noise also depended quasi-linearly on the mass in the slice. Some general performance rules were drafted to describe these effects and a preliminary correction algorithm was constructed.

Pus aspirated from acute suppurative oral infections in 78 patients (age range 13-76 years) yielded a total of 331 bacterial strains consisting of 143 facultative anaerobes (predominantly Streptococcus spp.) and 188 strict anaerobes (predominantly Prevotella spp.). Seventy-five isolates (23%) were resistant to penicillin (MIC > 1 mg/L), 37 (11%) were resistant to ampicillin (MIC > 2 mg/L) and 16 (5%) isolates were resistant to amoxycillin/clavulanic acid (MIC > 2 mg/L). Samples from 43 (55%) of the patients yielded at least one penicillin resistant isolate and within this group 30 samples (73%) contained at least one strain which produced beta-lactamase. A history of antibiotic therapy during the 6 months before enrollment in the study did not influence the isolation of penicillin resistant bacteria. It is concluded that penicillin resistant bacteria are often present in the microflora of acute dental infection.

OBJECTIVES: The aim was to investigate the relationship between bone mineral density (BMD) of the jaws (mandible and maxilla) and other skeletal sites. In addition, the influence of gender, smoking and the number of years without natural teeth were examined. MATERIALS AND METHODS: 18 edentulous patients (9 females, 9 males) with a mean age of 67.1 (sd 12.6) years had DXA scans to assess the BMD of the lumbar spine and hip, together with the ramus, body and symphysis of the mandible and the anterior of the maxilla. RESULTS: BMD values for the ramus were similar to those for the femur but significantly lower than the lumbar spine. The body and anterior mandible had higher values and the anterior maxilla lower values than both the femur and ramus. The ramus BMD showed moderately strong relationships with the standard measures of BMD in the spine and hip, but the BMD of other areas of the jaws showed no relationship with skeletal sites. The BMD for both the hip and the ramus showed an inverse relationship with increasing age. There was no statistically significant relationship between BMD of hip, spine and jaw and either years edentulous or cigarette years. (207) CONCLUSIONS: Although the ramus of the mandible may show correlation of BMD with skeletal sites, the areas of the jaws where implants may be placed do not. Therefore BMD of the skeletal sites could not be used to predict BMD of the jaws. The BMD of the jaws as measured by DXA showed no relationship with either years edentulous or cigarette smoking.

Oral submucous fibrosis (OSF) is a chronic progressive condition affecting the oral cavity, oropharynx and upper third of the oesophagus. It is a potentially malignant disorder. The authors collated and analysed the existing literature to establish the overall malignant transformation rate (MTR). A retrospective analysis of medical and dental scientific literature using online indexed databases was conducted for the period 1956 to 2021. The quality of the enrolled studies was assessed by the Newcastle-Ottawa Scale (NOS). A meta-analysis using a random effects model of a single proportion was performed along with statistical tests for heterogeneity. The overall proportion of malignancy across all studies was 0.06 (95% CI, 0.02-0.10), indicating an overall 6% risk of malignant transformation across all studies and cohorts. Sub-group analyses revealed strong differences in proportion of malignancy according to ethnicity/cohort; Chinese = 0.02 (95% CI 0.01-0.02), Taiwanese = 0.06 (95% CI, 0.03-0.10), Indian = 0.08 (95% CI, 0.03-0.14) and Pakistani = 0.27 (95% CI 0.25-0.29). Overall, the MTR was 6%; however, wide heterogeneity of the included studies was noted. Geographic variations in MTR were noted but were not statistically significant. Further studies are required to analyse the difference between cohort groups.

INTRODUCTION: Evidence concerning the interactions between human health and planetary health has grown extensively in recent years. In turn, the perceived importance of environmental sustainability within higher education is growing at a rapid rate. This paper provides a summary of key elements as they apply to dentistry, and provides an introduction to the reader of an early consensus of how sustainability could be included as part of the dental curriculum. METHODS: The consensus opinion within this paper largely centres around discussion at the ADEE sustainability workshop at the annual conference in Berlin (August 2019). In order to help inform discussions at the workshop, a brief scoping questionnaire was circulated to potential participants regarding their understanding and current teaching practices in sustainability. An infographic was designed to help delegates remember the important elements of sustainable dentistry. Delegates discussed the concept of sustainability alongside the infographic, and how they could link these with the Graduating European Dentist (GED) curriculum. RESULTS: The discussions within the workshop largely centred around 4 main themes: Disease prevention and health promotion, Patient education and empowerment, Lean service delivery and Preferential use of strategies with lower environmental impact. DISCUSSION: It is apparent that there is a widespread need for teaching materials relating to environmental sustainability; this includes specific learning outcomes relating to the 4 educational domains of the Graduating European Dentist curriculum, and methods for teaching and assessing these outcomes. CONCLUSION: This paper reports consensus on the first phase of a pan-European working group on Sustainability in dental education.

The effect of defined stresses on cantilevered prostheses attached to osseointegrated implants was assessed by finite element analysis. The effect of stress on a cantilever, consisting of a ductile alloy in contact with a brittle polymer, was demonstrated to be complex. The distribution of applied stresses also influenced the results. Possible fracture and distortion of both materials were demonstrated. Finite element analysis is a particularly useful system for predicting stress behavior and can be employed to produce an optimal prosthetic design that reduces the potential for clinical failure.

The aim of the present study was to evaluate the association of tongue posture with the dentoalveolar maxillary and mandibular morphology in a group of Class III subjects in comparison to a group of Class I subjects. Twenty Class III subjects (9 males, 11 females, 19.2 ± 4.6 years) and 20 Class I subjects (6 males, 14 females, 17.4 ± 1.7 years) were included in the present study. Maxillary and mandibular morphology was defined by the intermolar and intercanine distances, at both the cusps and gingival levels, and by measuring surface area and volume of the palatal vault and mouth floor assessed on three-dimensional digital models. Tongue-to-palate distances were measured on lateral cephalograms. The groups were compared using the Mann-Whitney U-test and correlations between each morphological parameter and the tongue-to-palate distances were calculated using the Spearman correlation coefficient. The mandibular intermolar width at the gingival level was significantly greater in the Class III group (P < 0.01), while the maxillary intercanine widths were significantly smaller in the Class III group (P < 0.05). The mouth floor area and volume and the respective ratios between the mouth floor and palate were significantly greater in the Class III group (P = 0.01). The tongue-to-palate distances were generally greater, i.e. lower tongue posture, for the Class III subjects. Significant correlations were seen between tongue-to-palate distances in the posterior region with the area ratio (rho = 0.44, P < 0.05). Tongue posture is significantly lower in Class III subjects and is associated with the dentoalveolar characteristics of the maxilla and mandible.

The aim of this article is to make clinicians aware of the use of cone beam computed tomography (CBCT) within the field of orthodontics. The paper describes five cases each one illustrating the improved diagnostic yield using CBCT over conventional radiography thus facilitating the appropriate treatment planning of patients.

BACKGROUND: Combination analgesics are effective in acute pain, and a theoretical framework predicts efficacy for combinations. The combination of dexketoprofen and tramadol is untested, but predicted to be highly effective. METHODS: This was a randomised, double-blind, double-dummy, parallel-group, placebo-controlled, single-dose trial in patients with moderate or severe pain following third molar extraction. There were ten treatment arms, including dexketoprofen trometamol (12.5 mg and 25 mg) and tramadol hydrochloride (37.5 mg and 75 mg), given as four different fixed combinations and single components, with ibuprofen 400 mg as active control as well as a placebo control. The study objective was to evaluate the superior analgesic efficacy and safety of each combination and each single agent versus placebo. The primary outcome was the proportion of patients with at least 50 % max TOTPAR over six hours. RESULTS: 606 patients were randomised and provided at least one post-dose assessment. All combinations were significantly better than placebo. The highest percentage of responders (72%) was achieved in the dexketoprofen trometamol 25 mg plus tramadol hydrochloride 75 mg group (NNT 1.6, 95% confidence interval 1.3 to 2.1). Addition of tramadol to dexketoprofen resulted in greater peak pain relief and greater pain relief over the longer term, particularly at times longer than six hours (median duration of 8.1 h). Adverse events were unremarkable. CONCLUSIONS: Dexketoprofen trometamol 25 mg combined with tramadol hydrochloride 75 mg provided good analgesia with rapid onset and long duration in a model of moderate to severe pain. The results of the dose finding study are consistent with pre-trial calculations based on empirical formulae. TRIAL REGISTRATION: EudraCT (2010-022798-32); Clinicaltrials.gov (NCT01307020).

Remodeling of collagen by matrix metalloproteinases (MMPs) is crucial to tissue homeostasis and repair. MMP-13 is a collagenase with a substrate preference for collagen II over collagens I and III. It recognizes a specific, well-known site in the tropocollagen molecule where its binding locally perturbs the triple helix, allowing the catalytic domain of the active enzyme to cleave the collagen α chains sequentially, at Gly(775)-Leu(776) in collagen II. However, the specific residues upon which collagen recognition depends within and surrounding this locus have not been systematically mapped. Using our triple-helical peptide Collagen Toolkit libraries in solid-phase binding assays, we found that MMP-13 shows little affinity for Collagen Toolkit III, but binds selectively to two triple-helical peptides of Toolkit II. We have identified the residues required for the adhesion of both proMMP-13 and MMP-13 to one of these, Toolkit peptide II-44, which contains the canonical collagenase cleavage site. MMP-13 was unable to bind to a linear peptide of the same sequence as II-44. We also discovered a second binding site near the N terminus of collagen II (starting at helix residue 127) in Toolkit peptide II-8. The pattern of binding of the free hemopexin domain of MMP-13 was similar to that of the full-length enzyme, but the free catalytic subunit bound none of our peptides. The susceptibility of Toolkit peptides to proteolysis in solution was independent of the very specific recognition of immobilized peptides by MMP-13; the enzyme proved able to cleave a range of dissolved collagen peptides.

The aim of this study was to develop an aesthetic index for the evaluation of complete unilateral cleft lip and palate (UCLP) repair. The reproducibility and validity of this index were evaluated. A pilot study was devised, in which photographic slides of 50 subjects with UCLP were evaluated by seven orthodontic examiners on two separate occasions. After determining levels of agreement, the original index was modified for use in a clinical study. A field study was undertaken during an audit of cleft repair outcome in Perth, Western Australia. The subjects were graded using direct observation by two trained examiners. Standardized photographs of these subjects were taken at the same time. These were later graded by the same examiners independently on two separate occasions. Direct and indirect patient gradings could therefore be compared. A further field study involved the evaluation of the photographic slides of the original 50 subjects by 22 cleft surgeons. Reproducibility was determined by calculation of weighted kappa statistics. The intra-examiner agreement ranged from moderate to good and inter-examiner agreement from fair to good. Comparison of direct and indirect aesthetic evaluation revealed that the agreement was moderate to good, and no significant systematic bias existed. The new index offers advantages in simplicity and flexibility. Its reproducibility compares favourably with other aesthetic indices, and is not affected by the subject's age.

Managing pain and anxiety in patients has always been an essential part of dentistry. To prevent pain, dentists administer local anaesthesia (LA) via a needle injection. Unfortunately, anxiety and fear that arise prior to and/or during injection remains a barrier for many children and adults from receiving dental treatment. There is a constant search for techniques to alleviate the invasive and painful nature of the needle injection. In recent years, researchers have developed alternative methods which enable dental anaesthesia to be less invasive and more patient-friendly. The aim of this review is to highlight the procedures and devices available which may replace the conventional needle-administered local anaesthesia. The most known alternative methods in providing anaesthesia in dentistry are: topical anaesthesia, electronic dental anaesthesia, jet-injectors, iontophoresis, and computerized control local anaesthesia delivery systems. Even though these procedures are well accepted by patients to date, it is the authors' opinion that the effectiveness practicality of such techniques in general dentistry is not without limitations.