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C D Stephens

Publications and source records attributed to C D Stephens.

At least 37 records · Page 2Linked to original sources
PubMed1988

Three-dimensional measurement: the accuracy and precision of the reflex metrograph.

The Reflex Metrograph is an optical plotter which is linked directly to a microcomputer and allows direct three-dimensional measurements of irregular shaped objects up to 300 mm maximum dimension without contacting the object. This study shows that it is possible to generate reproducible results with an operator measurement error of less than 0.2 mm for linear distances on objects up to 200 mm maximum dimension. The Reflex Metrograph tends to undermeasure by 0.67% or by up to 2.00 mm per 300 mm and is very slightly less accurate in the vertical plane. The potential use of this measuring instrument is discussed.

Cephalometry↗
PubMed1988

Three-dimensional measurement: the accuracy and precision of the Reflex Microscope.

The Reflex Microscope is an optical plotter which is linked directly to a microcomputer and allows direct three-dimensional measurements of irregular shaped objects up to 100 mm maximum dimension. This study shows that it is possible to generate reproducible results with an operator measurement error of less than 0.15 mm for linear distances. The Reflex Microscope tends to undermeasure by 0.28% or by up to 0.14 mm per 50 mm. There was no detectable difference in accuracy between the three planes X, Y and Z. In planes X and Y the two-dimensional accuracy at high magnification of a 1.000 mm scale was 1.004 mm in X and 1.008 mm in Y planes.

Computer Systems↗
PubMed1988

Changes in the complexity of orthodontic treatment for patients referred to a teaching hospital.

The records of 200 orthodontic patients accepted for treatment by the Orthodontic Department of the Bristol Dental Hospital in 1977 were compared with 200 taken on in 1985 in order to determine whether there had been any change in the proportion of referred cases requiring more complex procedures. Within each sample, cases were categorized as follows: (a) suitable for removable appliance treatment by an undergraduate or general practitioner; (b) requiring simple one arch fixed appliance treatment such as might be attempted by a general practitioner after a period of further training; (c) needing specialist treatment such as full multibracketed fixed appliances or orthognathic surgery. It was found that there had been no change in the proportions of simple and complex cases referred during the 8-year period although the proportion of patients now receiving complex treatment had increased greatly. Possible explanations and implications are discussed.

England↗
PubMed1988

A little distal archery.

Two instances are described in which the cutting of distal sections of archwires using current clinical methods has proved hazardous.

Finger Injuries↗
PubMed1985

Radiographs taken for orthodontic purposes in general practice.

This paper deals with the orthodontic aspects of a wider survey undertaken to determine the use of radiographs in general dental practice in the county of Avon. During the sample week 218 patients had radiography for orthodontic purposes of whom 184 were below the age of 15 years. There were marked differences in the radiographs used by general practitioners and specialist orthodontists and the possible reasons for these differences are discussed.

Adolescent↗
PubMed1985

Future manpower requirements for orthodontics undertaken in the General Dental Service.

The fall in the number of births in England and Wales which took place between 1964 and 1977 is beginning to have an effect on the present-day demand for orthodontic treatment. Using the best available data a mathematical model has been used to predict the likely demand for orthodontic treatment in the General Dental Services of England and Wales from now until 2008. This suggests that there is likely to be a sharp decline in the number of new orthodontic patients presenting for treatment at practices limited to orthodontics during the next 5 years. The recent expansion in the number of places available for postgraduate study of orthodontics makes it extremely unlikely that the position will improve significantly thereafter. There can be little doubt that we are now producing too many orthodontic specialists even allowing for the increase in manpower which might be required to satisfy a future demand for higher standards of treatment.

Dentists↗