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Biomedical subjects

K D O'Brien

Publications and source records attributed to K D O'Brien.

At least 19 recordsLinked to original sources
PubMed2006

Orthodontic treatment for deep bite and retroclined upper front teeth in children.

BACKGROUND: Correction of the type of dental problem where the bite is deep and the upper front teeth are retroclined (Class II division 2 malocclusion) may be carried out using different types of orthodontic treatment. However, in severe cases, surgery to the jaws in combination with orthodontics may be required. In growing children, treatment may sometimes be carried out using special upper and lower dental braces (functional appliances) that can be removed from the mouth. In many cases this treatment does not involve taking out any permanent teeth. Often, however, further treatment is needed with fixed braces to get the best result. In other cases, treatment aims to move the upper first permanent molars backwards to provide space for the correction of the front teeth. This may be carried out by applying a force to the teeth and jaws from the back of the head using a head brace (headgear) and transmitting this force to a part of a fixed or removable dental brace. This treatment may or may not involve the removal of permanent teeth. In some cases, neither functional appliances nor headgear are required and treatment may be carried out without extraction of any permanent teeth. Instead of using a headgear, in certain cases, the back teeth are held back in other ways such as with an arch across or in contact with the front of the roof of the mouth which links two bands glued to the back teeth. Often in these cases, two permanent teeth are taken out from the middle of the upper arch (one on each side) to provide room to correct the upper front teeth. It is important for orthodontists to find out whether orthodontic treatment only, carried out without the removal of permanent teeth, in children with a Class II division 2 malocclusion produces a result which is any different from no orthodontic treatment or orthodontic treatment only involving extraction of permanent teeth. OBJECTIVES: To establish whether orthodontic treatment, carried out without the removal of permanent teeth, in children with a Class II division 2 malocclusion, produces a result which is any different from no orthodontic treatment or orthodontic treatment involving removal of permanent teeth. SEARCH STRATEGY: The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE were searched. The handsearching of the main international orthodontic journals was updated to April 2006. There were no restrictions with regard to publication status or language of publication. International researchers, likely to be involved in Class II division 2 clinical trials, were contacted to identify any unpublished or ongoing trials. SELECTION CRITERIA: Trials were selected if they met the following criteria: randomised controlled trials (RCTs) and controlled clinical trials (CCTs) of orthodontic treatments to correct deep bite and retroclined upper front teeth in children. DATA COLLECTION AND ANALYSIS: Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were to be conducted in duplicate and independently by two review authors. Results were to be expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. MAIN RESULTS: No RCTs or CCTs were identified that assessed the treatment of Class II division 2 malocclusion in children. AUTHORS' CONCLUSIONS: It is not possible to provide any evidence-based guidance to recommend or discourage any type of orthodontic treatment to correct Class II division 2 malocclusion in children.

Child↗
PubMed2006

Academic dentistry--where is everybody?

If someone had told us, when we were undergraduates, that there was a career which allowed you the time, and gave you the support, to pursue and research the things about your profession which most interested you, we would have been intrigued. If we had then been informed that there was paid employment which encouraged you to travel extensively abroad, talking about your work, and also gave you the brightest young minds in the country to engage with, teach and learn from, we would have thought this job sounded very tempting. If we had then been told that it also provided secretaries and administrators to help you do your job, and was carried out in a non-hierarchical, collegiate environment where equality and diversity are valued--we would have jumped at the chance! And did! Because what is described above is the life of a clinical academic. Although all the above are part of the role of the academic, there is also immense value and joy to be obtained through scholarship, education and teaching, which are sometimes forgotten because so much of our time and energy is directed to dealing with our patients' problems, while wrestling with the intricacies of new contracts, clinical governance, evidence based practice, and so forth.

Academic Medical Centers↗
PubMed2005

Teledentistry for screening new patient orthodontic referrals. Part 1: A randomised controlled trial.

OBJECTIVE: The primary aim was to evaluate the validity of a teledentistry system for screening new patient orthodontic referrals. The secondary aims were to evaluate whether the teledentistry system affected i) referral rates ii) inappropriate referral rates iii) number of failed appointments. STUDY DESIGN: Randomised controlled trial. SAMPLE: Fifteen dental practices in Greater Manchester, UK, were randomly allocated to either a teledentistry test group (n = 8) or a control group (n = 7). They referred 327 patients over a 15 month period. METHOD: Practitioners in the test group referred patients to one of two consultant orthodontists via a 'store and forward' teledentistry system consisting of photographs sent as email attachments. The decision to accept or not accept a referral on this basis was compared with the same decision choice when the same patient was subsequently seen on a new patient clinic. This measured the validity of the system with the clinic's decision used as the gold standard. Patients in the control group were referred using the usual letter system. Referral rates, inappropriate referrals and number of failed appointments were then compared between the teledentistry and control groups. RESULTS: The sensitivity (true positive value) of the teledentistry system was high at 0.80 with a positive predictive value of 0.92. The specificity (true negative value) was slightly lower at 0.73 with a negative predictive value of 0.50. The inappropriate referral rate for the teledentistry group was 8.2% and for the controls 26.2% (p = 0.037). There was no statistically significant difference in clinic attendance between teledentistry and control groups (p = 0.36). CONCLUSIONS: Teledentistry is a valid system for positively identifying appropriate new patient orthodontic referrals. However, there is a risk that a patient is not accepted on the teledentistry system who would benefit from a full clinical examination. Teledentistry could be a significant factor in reducing the inappropriate referral rate. Patient participation in a teledentistry system does not appear to mean they are any more likely to attend their hospital appointment.

Adolescent↗
PubMed2003

The use of postal reminders to reduce non-attendance at an orthodontic clinic: a randomised controlled trial.

OBJECTIVES: To evaluate the effect of issuing a patient reminder plus a confirmation slip on the attendance of orthodontic new patients. SETTING: Department of Orthodontics, University Dental Hospital of Manchester. DESIGN: A randomised controlled trial. METHODS: New patients were randomly allocated to:receive a reminder letter and return a confirmation slip ornot receive a reminder. OUTCOME MEASURES: Patient attendance at the clinic. RESULTS: A total of 232 patients were entered into the study between June 18, 2001 and August 29, 2001. These were randomly allocated to 115 (49.8%) in the reminder group and 116 (50.2%) in the no reminder group. If the patient received a reminder and returned the confirmation they were less likely to fail the appointment than if they did not receive a reminder (OR 0.4, 95% CI 0.2 to 0.96) There was an effect of social deprivation, if the patients lived in an area of high social deprivation they were 2.7 (95% CI 1.1 to 6.5) times more likely to fail to attend an appointment than people who were more affluent. CONCLUSIONS: The use of postal reminders for orthodontic consultation appointments appears to result in a useful increase of appointments that are kept or cancelled in advance.

Appointments and Schedules↗
PubMed2003

The effect of apolipoprotein E deficiency on islet amyloid deposition in human islet amyloid polypeptide transgenic mice.

AIMS/HYPOTHESIS: Islet amyloid deposits are present in over 85% of Type 2 diabetic patients and have been suggested to be pathogenic. The mechanism that converts islet amyloid polypeptide (IAPP), the unique component of these deposits, into amyloid fibrils in vivo is not known. The amino acid sequence of IAPP is critical but insufficient for beta-pleated sheet formation. As apolipoprotein E (apoE), another component of islet amyloid deposits, plays a critical role in amyloid formation in Alzheimer's disease, we hypothesised that apoE could play an important role in islet amyloid formation. METHODS: Transgenic mice expressing the human form of IAPP ( hIAPP (+/0)) were crossbred with apoE deficient ( apoE (-/-)) mice and followed for 12 months, at which time the prevalence and severity of islet amyloid, as well as plasma glucose, hIAPP, immunoreactive insulin (IRI) and lipid concentrations were measured. RESULTS: The prevalence and severity of islet amyloid after one year of follow up were comparable among hIAPP (+/0) mice that were apoE (+/+), apoE (+/-) or apoE (-/-). Differences in glucose tolerance, lipid abnormalities or changes in pancreatic content or plasma concentrations of hIAPP and/or IRI did not account for these findings. CONCLUSION/INTERPRETATION: Our data shows that, unlike in the localized amyloidosis in the brain characteristic of Alzheimer's disease, apoE is not critical for islet amyloid formation in a transgenic mouse model of Type 2 diabetes mellitus. These results indicate that the mechanisms of localised amyloid formation probably vary among different amyloid-associated disorders. Therefore, therapeutic strategies targeting apoE might not apply equally to patients with different amyloid associated diseases.

Amyloid↗
PubMed2002

Orthodontic teaching practice and undergraduate knowledge in British dental schools.

AIM: The aim was to survey current orthodontic teaching practice in the undergraduate syllabus at British dental schools and to test the abilities of undergraduate students according to the requirements of the GDC regulations. MATERIALS AND METHODS: Information collected by means of a questionnaire sent to each dental school in 1998 was compared with similar data from 1994. The orthodontic knowledge and treatment planning ability of students was assessed by a multiple-choice examination paper completed by a random 10% sample of students from each dental school. RESULTS: In 1998 on average 195 curriculum hours were devoted to orthodontics and each student treated five patients. The teaching of fixed appliances had increased considerably between 1994 and 1998. The average MCQ score was 58% (range 39-72%). Students scored well on questions that tested basic knowledge but much less well when they were required to apply that knowledge. Only three schools felt that it was realistic to expect undergraduates to formulate orthodontic treatment plans, as they are required to do by the GDC. CONCLUSION: Results support the view that undergraduate orthodontic training should concentrate on diagnosis and recognition of problems rather than on providing limited exposure to treatment techniques.

Clinical Competence↗
PubMed2002

So you want to be a specialist registrar?--What to put in your CV.

Dentists applying to a specialist training programme often receive conflicting advice over what to put in their curriculum vitae (CV). We conducted a survey of the Training Programme Directors of the dental specialties to determine what aspects of CV content and presentation styles are considered important. This has allowed us to construct guidelines for what to put in a CV. Recently, structured application forms have become increasingly popular and may be a more objective way to carry out the shortlisting process. The guidelines presented could also be used as a framework for medical personnel departments if structured application forms eventually replace the CV.

Career Mobility↗
PubMed2002

Upper removable appliance or Jones Jig for distalizing first molars? A randomized clinical trial.

AIM: To compare the effectiveness of two intra-oral methods of distalizing upper first permanent molars: an upper removable appliance (URA) and a Jones Jig. SAMPLE: Twelve patients were randomly allocated to URA treatment and 11 patients to a Jones Jig. METHODS: Upper study models were collected at the start of treatment and after 6 months of appliance wear. The amount of distal movement, tipping and rotation of the upper first permanent molars and mesial movement of the upper first permanent premolars was measured using a reflex metrograph. RESULTS: There were no statistically significant differences between the two treatment methods for any of the outcome measures (P < 0.05). Distal movement obtained by both appliances was approximately 1 mm. CONCLUSIONS: The amount of distal movement obtained with both appliances was small and no differences were shown in the amount of molar tooth movement. It is suggested that there is no advantage in using the Jones Jig as a non-compliance appliance.

Adolescent↗
PubMed2002

A randomized clinical trial to compare three methods of orthodontic space closure.

AIM: To compare the rates of orthodontic space closure for: Active ligatures, polyurethane powerchain (Rocky Mountain Orthodontics, RMO Europe, Parc d'Innovation, Rue Geiler de Kaysersberg, 67400 Illkirch-Graffenstaden, Strasbourg, France) and nickel titanium springs. SAMPLE: Patients entering the space closure phase of fixed orthodontic treatment attending six orthodontic providers. Twelve patients received active ligatures (48 quadrants), 10 patients received powerchain (40 quadrants) and 11 patients, nickel-titanium springs (44 quadrants). METHOD: Patients were randomly allocated for treatment with active ligatures, powerchain or nickel titanium springs. Upper and lower study models were collected at the start of space closure (T(o)) and 4 months later (T(1)). We recorded whether the patient wore Class II or Class III elastics. Space present in all four quadrants was measured, by a calibrated examiner, using Vernier callipers at T(o) and T(1.) The rate of space closure, in millimetres per month (4 weeks) and a 4-monthly rate, was then calculated. Examiner reliability was assessed at least 2 weeks later. RESULTS: Mean rates of space closure were 0.35 mm/month for active ligatures, 0.58 mm/month for powerchain, and 0.81 mm/month for NiTi springs. No statistically significant differences were found between any methods with the exception of NiTi springs showing more rapid space closure than active ligatures (P < 0.05). There was no effect of inter-arch elastics on rate of space closure. CONCLUSIONS: NiTi springs gave the most rapid rate of space closure and may be considered the treatment of choice. However, powerchain provides a cheaper treatment option that is as effective. The use of inter-arch elastics does not appear to influence rate of space closure.

Adolescent↗
PubMed2002

A randomized clinical trial to compare the effectiveness of canine lacebacks with reference to canine tip.

AIM: To assess the effectiveness of canine lacebacks on the proclination of the upper incisors with reference to pre-treatment canine tip. STUDY DESIGN: Randomized clinical trial. SAMPLE: Patients receiving upper and lower fixed appliances attending the orthodontic departments of five orthodontic treatment providers. Sixteen patients received canine lacebacks as part of their treatment and 19 patients did not have canine lacebacks. METHOD: Patients were randomly allocated to receive canine lacebacks or not receive canine lacebacks. Upper study models were collected at the initial archwire placement and then when the working 0.019 x 0.025-inch stainless steel archwire was placed. The start canine angulation, change in upper incisor proclination/overjet, and any mesial movement of the upper first permanent molars during levelling and aligning was measured with a reflex metrograph. STATISTICS: The effect of the use of canine lacebacks on upper incisor proclination and mesial molar movement was assessed using Student t-tests. Regression analysis was used to evaluate any effect of the initial angulation of the canine. RESULTS: A mean incisor retroclination of 0.5 mm was observed in the canine lacebacks compared with a mean proclination of 0.36 mm when canine lacebacks were not used (P = 0.025). There was no statistically significant difference between groups for mesial movement of upper first molars (P = 0.99). If the canine was more distally inclined at the start of treatment, the incisors was more likely to procline, regardless of whether or not canine lacebacks were used (P = 0.027). CONCLUSIONS: The effect of canine lacebacks on preventing upper incisor proclination at the start of treatment is in the order of 1 mm and their effect on mesial molar movement is insignificant. Canines lacebacks have similar effects that are independent of pre-treatment canine angulation.

Adolescent↗
PubMed2001

Orthodontics and occlusion.

The discipline of orthodontics is directed towards alteration of the occlusion of the teeth and the relationships of the jaws. It is therefore somewhat surprising to find that there is little scientific evidence to support any of the concepts that suggest occlusal goals for orthodontic treatment. Most of the current concepts of orthodontic treatment are based upon personal opinion and retrospective studies. Nevertheless, an attempt is made here to provide a guide to the relationship of orthodontics and the occlusion that is evidence based. Where the evidence is weak, these areas have been highlighted.

Centric Relation↗
PubMed2001

The relationship between normative orthodontic treatment need and measures of consumer perception.

AIM: The first aim was to investigate whether there was an association between normative (clinician measured) orthodontic treatment need and the following consumer values, 1) child self-perceived aesthetic need, 2) child self-esteem, 3) oral aesthetic subjective impact score (OASIS). The secondary aim was to investigate whether there was an association between child self-esteem and 1) child self-perceived aesthetic need 2) OASIS. STUDY TYPE: Prospective, cross-sectional. SAMPLE: A random sample of 439, 11-12 year-old children was selected from schools in Greater Manchester. METHOD: Normative and child self-perceived orthodontic treatment need were measured using the Index of Orthodontic Treatment Need (IOTN). The subjects completed questionnaires to measure their self-esteem (Piers Harris) and OASIS score. RESULTS: Children with higher normative IOTN scores had more negative psycho-social impact from their malocclusion (P<0.001). However, there was no association between clinician IOTN grades and child self-esteem. Clinician and child-rated IOTN aesthetic component (IOTN AC) grades were statistically significantly different (P<0.05). Higher child self-esteem scores were associated with lower child rated IOTN AC grades (P<0.05) and lower OASIS scores (P<0.001). CONCLUSIONS: Only one of the consumer measures studies (OASIS) reflected normative/clinician IOTN grades. A high child self-esteem appears to be related to their self-perceived malocclusion and its psycho-social impact. It is still important to have additional information derived from consumer based measures rather than rely solely on normative measures of need. It remains to be seen whether these factors subsequently influence demand and uptake of orthodontic treatment.

Attitude to Health↗
PubMed2000

Expression of cellular FLICE-inhibitory protein in human coronary arteries and in a rat vascular injury model.

We previously isolated MACH-related inducer of toxicity (MRIT), a homolog of caspase 8. MRIT, also known as c-FLICE-inhibitory protein (c-FLIP), is an enzymatically inactive homolog of caspase 8 with homology to viral FLIP (v-FLIP). Because of this homology and resemblance to dominant negative proteins, c-FLIP is widely believed to be an antagonist to the death receptor-initiated apoptotic pathways that use caspase 8. We generated a polyclonal antibody, MAG1, and show that this antibody specifically recognizes two splice forms, long form (c-FLIPL) and short form (c-FLIPS). By in situ hybridization and immunohistochemistry, we demonstrate that c-FLIP is expressed in endothelial cells, macrophages, and smooth muscle cells (SMCs) both in human coronary arteries and in cultured cells. In an uninjured rat carotid arteries, c-FLIP protein is abundant in the vascular media. After balloon angioplasty, c-FLIP protein is rapidly down-regulated in medial SMCs for 2 weeks and regains expression by 4 weeks. In contrast, the neointima is strongly immunoreactive to c-FLIP from day 7 after the initial injury and remains strongly immunoreactive until 4 to 6 weeks. Similarly there is strong c-FLIP immunoreactivity in SMCs from nonatherosclerotic diffuse intimal thickening and in the overlying endothelial cells. In contrast, c-FLIP immunoreactivity is uneven and often absent in SMCs within the atherosclerotic plaque. Double labeling with c-FLIP antibody and terminal deoxynucleotidyltransferase-mediated UDP end labeling (TUNEL) in the injured rat common carotid artery show that TUNEL-positive cells in the first 2 days after injury lack detectable c-FLIP, suggested a role for caspase 8 in this form of death. In contrast, there is no correlation of c-FLIP with the spontaneous elevation in death of intima seen at 7 days after injury. For human atherosclerotic plaques, the majority of TUNEL-positive cells lack detectable c-FLIP. The expression pattern of c-FLIP and the relation between c-FLIP and TUNEL suggest a role for c-FLIP- and caspase 8-driven death in control of viability of the cells of the atherosclerotic intima.

Adult↗
PubMed2000

Cellular FLIP is expressed in cardiomyocytes and down-regulated in TUNEL-positive grafted cardiac tissues.

OBJECTIVE: c-FLIP is a natural homologue of caspase 8, and may antagonize activation of death pathways mediated by FADD. c-FLIP is highly expressed in the heart, and a recent report suggests that c-FLIP may protect against certain types of myocyte death. The present study was designed to define the expression patterns of c-FLIP in the heart. METHODS: The expression pattern of c-FLIP in end-stage human hearts, and rat cardiomyocyte grafting models was analyzed by in situ hybridization, immunohistochemistry and TUNEL assay. In addition, to determine whether Fas-dependent pathway is active in cardiomyocytes in vitro, we examined whether activated monocytes can kill neonatal cardiomyocytes in a co-culture system. RESULTS: c-FLIP mRNA and protein were abundantly expressed in normal cardiomyocytes from failing human heart. In animal models, c-FLIP protein was absent in TUNEL-positive grafted cardiomyocytes. Double staining demonstrated that c-FLIP-positive cells rarely had fragmented DNA, while TUNEL-positive cells rarely contained c-FLIP. Finally, activated monocytes induced death of neonatal rat cardiomyocytes via the Fas/FasL system. CONCLUSIONS: Loss of c-FLIP expression correlates with cardiomyocyte cell death. We hypothesize that diminished c-FLIP expression may predispose cardiomyocytes to apoptotic death.

Adult↗
PubMed2000

Perceived aesthetic impact of malocclusion and oral self-perceptions in 14-15-year-old Asian and Caucasian children in greater Manchester.

The aims of this study were to evaluate (i) the effect of ethnicity, social deprivation, and normative orthodontic treatment need on orthodontic aesthetic self-perception, self-perceived need for orthodontic treatment, and oral aesthetic impact of malocclusion; (ii) the effect of ethnicity, social deprivation, and gender on perceived orthodontic treatment need and use of orthodontic services; (iii) the influence of perceived oral aesthetic impact of malocclusion on perceived need and wish for orthodontic treatment; and (iv) whether orthodontic treatment experience influences perceived oral aesthetic impact of malocclusion. A stratified, random sample of 434 14-15-year-old children from schools in Manchester, UK, was obtained. Information was collected on orthodontic aesthetic self-perception and orthodontic treatment experience using a questionnaire. The former data were combined to form an Oral Aesthetic Subjective Impact Scale (OASIS). Normative orthodontic treatment need was measured with the Index of Orthodontic Treatment Need (IOTN). Children with higher clinical need for orthodontic treatment perceived themselves as worse off than their peers with lower need. More socially deprived children or those with high IOTN aesthetic component (AC) scores had a higher (i.e. more negative) aesthetic impact (OASIS) score. Asians and females had higher IOTN dental health component (DHC) scores, but a better aesthetic appearance than Caucasians and males. More deprived children were less likely to have received orthodontic treatment. Despite this, OASIS scores were similar between treated and untreated children. Untreated children who wished for orthodontic treatment had higher IOTN AC and OASIS scores.

Adolescent↗
PubMed1999

The consultant orthodontic service--1996 survey.

OBJECTIVE: To evaluate the working patterns and facilities of the consultant orthodontist service. DESIGN: A cross-sectional survey. SETTING: Consultant orthodontist departments in the UK. SUBJECTS AND METHODS: All consultant orthodontists in the UK were sent a questionnaire that gathered information on the individual consultant, the facilities available, the new patients referred and patients under current treatment. RESULTS: The consultant orthodontist service provided treatment to a high number of patients who were in definite need of orthodontic treatment. A marked reduction in the use of removable appliances suggests improving standards of care and provision of more complex treatment. The caseload was high and a fair proportion of patients were returned to their referring dentists with treatment plans. The consultant service has not completely evolved into a service that provides treatment at a super-specialist level alone. CONCLUSIONS: There has been little change in the consultant orthodontist service over the past ten years. Arguably, this is because of the wishes of the purchasers and the shortage of trained orthodontic manpower as a direct result of poor manpower planning and lack of funds for post-graduate training.

Cross-Sectional Studies↗