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Biomedical subjects

K D O'Brien

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

66 records · Page 4Linked to original sources
PubMed1991

Quality control in orthodontics: factors influencing the receipt of orthodontic treatment.

The factors which influence the uptake of orthodontic treatment are reviewed with respect to the features and aspirations of the consumers (patients and parents) and the providers (dentists, orthodontists and health system). It appears that the assessment of orthodontic treatment need is influenced by many variables relating to opportunity and demand for treatment; this results in a marked lack of uniformity in treatment uptake.

Adolescent↗
PubMed1991

Quality control in orthodontics: risk/benefit considerations.

The literature concerning risk/benefit appraisal for orthodontic treatment is reviewed with respect to factors which influence dental health, social psychological well-being and the harmful effects of orthodontic treatment. There is little evidence to suggest that the absence of malocclusion is associated with a measurably higher self-esteem and life fulfillment, or with major advantages for dental health, except for a limited number of traits. With regard to treatment, small risks of iatrogenic harm exist, while the effects of partial or total failure of treatment, and the lack of long-term stability of results should not be underestimated.

Adolescent↗
PubMed1991

Light cured direct bonding--is it necessary to use a primer?

A study was undertaken to assess the influence of a low viscosity unfilled 'primer' resin upon the shear bond strength of a bracket adhesive combination to etched enamel and at the separate interfaces of the bonding system, namely the bracket/adhesive and the enamel/adhesive interfaces. No significant differences were detected between the bond strengths when an unfilled resin phase was utilized (P greater than 0.05).

Acid Etching, Dental↗
PubMed1990

The specialist orthodontic practitioner. The 1989 survey.

In 1989, a survey of specialist orthodontic practitioners was carried out, with the cooperation of the British Association of Orthodontists. Questionnaires were sent to all BAO members in full-time specialist orthodontic practice; a 72% response was achieved. The results revealed that the specialist orthodontic practitioner service was well equipped and adequately qualified to accept a role as providers of the majority of UK orthodontic treatment. When new patient treatments were analysed, it was found that fixed appliance treatment was proposed for 60% of patients. However, the majority of the respondents felt that the system of remuneration in the GDS encouraged quantity as opposed to quality of treatment.

Adult↗
PubMed1990

A clinical trial of an indirect bonding technique with a visible light-cured adhesive.

A trial was carried out to evaluate the clinical performance of a visible light-cured adhesive when used with a foil mesh base in an indirect bonding technique. Thirty-seven patients entered the trial, and a total of 407 brackets were placed. The incidence and site of bond failure were recorded. The overall failure rate was 6.5%. There were no significant differences detected between the failure rates for either the upper or the lower arches or for the anterior and the posterior segments of the arches (p less than 0.01).

Acrylates↗
PubMed1989

A visible light-activated direct-bonding material: an in vivo comparative study.

A clinical trial was carried out to evaluate and compare the clinical performance of a visible light-cured material with a chemically cured adhesive. This was used in combination with two types of bracket base. Fifty-two patients entered the trial and 542 bracket bases were placed. The incidence and site of bond failure were recorded. The overall failure rate for the light-cured material in combination with both types of bracket was 4.7% and 6% for the chemical-cured adhesive. There were no significant differences detected between the failure rates for both types of adhesive in combination with either bracket base, and no bracket base/adhesive combination proved superior (p greater than 0.05). When the data were examined in an overall manner, a significantly higher posterior tooth failure rate was detected for all adhesive/base combinations (p less than 0.001).

Adolescent↗
PubMed1989

Regional variation in the provision and cost of General Dental Service orthodontic treatment in England and Wales.

The regional distribution of orthodontic treatment provision through the General Dental Service was examined, with reference to, per capita spending, cost per case and treatment rate; a marked regional variation in these variables was detected. The regional distributions of the specialist orthodontic practitioner and the General Dental Practitioner were calculated; and also exhibited a marked regional variation. The relationships between the regional distributions of manpower treatment rate and spending on orthodontic treatment were calculated. It was found that there were significant relationships between the regional distribution of manpower and treatment rate and per capita spending, but not cost per case. Possible explanations are discussed.

Adolescent↗
PubMed1988

Residual debris and bond strength--is there a relationship?

A study was undertaken to test the theory that there is a relationship between bond strength at the separate interfaces of the direct bonding system and the amount of residual debris remaining on the enamel surface following removal of a bonded appliance. In separate experiments, shear loads were applied at the complete direct bonding system and at the separate interfaces--namely, those at the adhesive/enamel and the adhesive/bracket base--using a chemically cured and a visible light-cured materials in combination with two designs of bracket bases. An assessment of residual debris following bond failure was made. For the complete direct bonding system, analysis showed that a foil mesh/chemically cured adhesive combination produces significantly more residual debris on the enamel than any other combination (P less than 0.05). No significant differences (P greater than 0.05) in shear bond strengths were detected for any bracket base/adhesive/enamel combination. Furthermore, no significant differences (P greater than 0.05) were detected between the shear bond strengths at the adhesive/enamel and adhesive/bracket base interfaces. These results suggest that the amount of residual debris following removal of the bonded bracket is not related to the shear bond strength at the separate interfaces but is governed by factors caused by bracket base design and properties of the adhesive used.

Adhesiveness↗
PubMed1988

Expanded function orthodontic auxiliaries; a proposal for their introduction in the UK.

The role of dental and orthodontic auxiliaries in Europe and the United States is reviewed, and the advantages of their employment in the United Kingdom are discussed in terms of increasing the cost-effectiveness of orthodontic treatment provision. A three-stage programme for the evaluation of Orthodontic Auxiliaries in the UK is proposed.

Dental Assistants↗
PubMed1985

Current trends in antifertility vaccine research.

We review the major advances that have recently occurred in the area of antifertility vaccines by examining the immunogenic potential of gamete, embryonic and placental antigens. In human trials using beta-human chorionic gonadotropin coupled with tetanus toxoid as the immunogen, the major problems with antifertility vaccines relate to specificity and maintaining an adequate antibody titer to disrupt gestation. Possible complications include cross-reaction with other body tissues, immune complex deposition, cytotoxicity, impaired immunologic tumor surveillance and nonreversibility.

Adjuvants, Immunologic↗
PubMed1984

Lymphocytic bronchitis unrelated to acute graft-versus-host disease in canine marrow graft recipients.

We reviewed coded autopsy material from 71 dogs, 46 receiving allogeneic and 25 receiving autologous bone marrow transplants, to evaluate the hypothesis that lymphocytic bronchitis is associated with severe acute graft-versus-host disease (GVHD). We found no significant correlation between the presence of lymphocytic bronchitis and severe acute GVHD (P greater than 0.16). Using a binary regression model that corrected for possible confounding relationships, we failed to show a correlation between lymphocytic bronchitis and acute GVHD of each of the 3 classically affected organ systems. Also, no correlation was found between lymphocytic bronchitis and acute bacterial pneumonia (P greater than 0.32). Finally, lymphocytic bronchitis was present in autografted dogs with a prevalence at autopsy not significantly different from that of allografted dogs (P greater than 0.32). We conclude that lymphocytic bronchitis in this canine model represents nonspecific inflammation rather than acute pulmonary GVHD.

Acute Disease↗