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Biomedical subjects

W C Shaw

Publications and source records attributed to W C Shaw.

At least 73 records · Page 4Linked to original sources
PubMed1992

A six-center international study of treatment outcome in patients with clefts of the lip and palate: Part 5. General discussion and conclusions.

Part 5 is the final part of a series of five articles reporting on an international, multicenter clinical audit of treatment outcome for complete UCLP. A number of recommendations for the methodology of future studies is made especially with respect to entry criteria, sample size, assumptions of homogeneity, and the reproducibility and validity of outcome measures. The findings of the present study regarding clinical procedures are presented tentatively, and improvement and extension of the methodology are required. It appears, however, that acceptable results can be achieved by different programs and ultimately clinical choices may be based on factors such as complexity, costs, and demands of treatment. Standardization, centralization, and the participation of high volume operators were associated with good outcomes, and nonstandardization and the participation of low volume operators with poor outcomes. Therapeutic factors associated with good outcomes were the employment of a vomer flap to close the anterior palate, and poor outcomes with primary bone grafting and with active presurgical orthopedics.

Bone Transplantation↗
PubMed1992

Loss of the first permanent molar and caries experience of adjacent teeth.

The caries experience of the occlusal and distal surfaces of the second premolars and the occlusal and mesial surfaces of the second permanent molars was examined in four groups of subjects aged 19-20 years. Group 1 comprised subjects with first permanent molars present, Group 2 subjects with early loss of the first permanent molar (before the age of 11-12 years), Group 3 subjects with late loss of the first permanent molar (after 11-12 years but before 15-16 years) and Group 4 included a combination of Group 2 and Group 3. Loss of the first permanent molar was associated with increased caries or restorations in the occlusal surfaces of adjacent teeth, but reduced caries or restorations in the proximal surfaces of adjacent teeth. Early loss of the first molar was associated with significantly greater caries or restoration experience in proximal surfaces than late loss, but no difference was detected for occlusal surfaces.

Adolescent↗
PubMed1992

Results of multidisciplinary management of bilateral cleft lip and palate at the Iowa Cleft Palate Center.

Bilateral cleft of the lip and palate is by many standards the most complex and severe form of the defect. The complexity and severity of the defect require an unusual degree of cooperation among all specialists and especially between the surgeon and the orthodontist. There are no published findings that we know about in which comprehensive data from a number of disciplines are reported for the same group of bilateral cleft patients. Fifty randomly selected patients with bilateral complete clefts were examined by the Iowa team and two orthodontists from other institutions. The evaluations revealed that a large number of patients over the age of 10 have multiple residual problems requiring further treatment. Only 23 percent of the older patients studied were judged to have had treatment completed by the surgeon, speech pathologist, and orthodontist. It is very difficult to state whether the results obtained by our team can be considered satisfactory because there are no comparable studies that have attempted to evaluate the same parameters in multidisciplinary management.

Adolescent↗
PubMed1991

Quality control in orthodontics: indices of treatment need and treatment standards.

Two reliable and valid occlusal indices have been developed to assess treatment need (Index of Treatment Need, IOTN) and the standard of treatment (The PAR Index, Peer Assessment Rating). The IOTN assesses both dental aesthetics and dental health need. The PAR index provides a single summary score for the overall alignment and occlusion. The difference between the pre- and post-treatment scores reflects the degree of improvement and the success of orthodontic intervention and active treatment. Several practical uses of the indices are described: the estimation of treatment need in an unselected and a referred population and the assessment of the standard of treatment in the Hospital and General Dental Services. It has been suggested that the use of the occlusal indices would offer several advantages: (1) uniformity in prescribing patterns, (2) safeguards for the patient, (3) patient counselling and (4) monitoring and promoting standards.

Discriminant Analysis↗
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

The effect of orthodontic treatment on plaque and gingivitis.

The aim of the present investigation was to evaluate the relationship between the receipt of orthodontic treatment and subsequent periodontal health. Data from 417 children who were classified at baseline as having significant occlusal variations and who were present at the follow-up examination 3 years later were selected from an original cohort of 1015. One hundred fourteen of these children received orthodontic treatment over this time period and provided two groups of children for comparison in this study. Plaque indices, bleeding indices, and degree of dental irregularity were recorded for each incisor and canine tooth. There were significant reductions in the plaque and gingivitis scores on all tooth surfaces between the baseline and 3-year examination in the two groups of children. The children who had received orthodontic treatment had the greater reduction, but this appeared to be more related to behavioral factors than to improved tooth alignment.

Adolescent↗
PubMed1991

A survey of craniomandibular disorders in 1000 12-year-olds. Study design and baseline data in a follow-up study.

One-thousand-and-eighteen 12-year-old children were chosen by use of preselected screening criteria, and disproportionate sampling to participate in a longitudinal study into the dental and social effects of malocclusion. The data has now been used to investigate the effects of malocclusion and orthodontic treatment on craniomandibular disorders. The sampling method was designed to create sub-groups large enough to study effectively the whole range of malocclusion, even those which have a low prevalence. This report will give baseline data in a longitudinal study. Intra-observer variability on recordings of signs of craniomandibular disorders was tested and reproducibility was found to be on an acceptable level. Almost half the children had signs of CMD, but few of these were severe and overall, only a very small minority of children in this sample required treatment. A preliminary examination has been made into possible relationships between the signs and symptoms of CMD, and significant associations were found between headache and several clinical signs.

Chi-Square Distribution↗
PubMed1991

Simonart's band and facial growth in unilateral clefts of the lip and palate.

A cephalometric analysis was carried out to see if the presence of a Simonart's band at birth was associated with a detectable difference in subsequent craniofacial form. Mixed longitudinal data from 5 through 18 years of age was analyzed for 257 individuals with complete UCLP included in the Oslo CLP Growth Archive, 80 with a Simonart's band and 177 without. No major differences were detected between individuals with or without Simonart's band, though the presence of a Simonart's band was associated with a larger cranial base angle and a slightly more favorable maxillomandibular relationship. The findings are discussed in relation to embryogenesis, primary surgery, and secondary surgery. It is recommended that cephalometric studies of UCLP involving group comparisons should avoid major imbalance with respect to the proportion of individuals with a Simonart's band at birth.

Adolescent↗
PubMed1991

Strategies for the advancement of surgical methods in cleft lip and palate.

This paper examines the clinical research methodologies used for the evaluation of cleft lip and palate therapies. A survey of clinical reports in the Cleft Palate Journal between 1964 and 1988 revealed that almost all used retrospective methods (96%). The authors examine the merits and biases associated with retrospective evaluation of therapies and compared these to prospective randomized clinical trials. The strengths and weaknesses of clinical trials are discussed in relation to the long-term evaluation of primary surgery in cleft patients. For these to be successful, further work is needed to investigate questions such as sample size, possible predictors of long-term outcome, and improved methods of presurgical assessment. The authors conclude that if the uncertainties associated with the choice of primary cleft surgery are to be resolved, the challenge of multicenter prospective clinical trials must be faced by the various disciplines involved in cleft palate clinical research.

Cleft Lip↗
PubMed1991

Development of a method for rating nasolabial appearance in patients with clefts of the lip and palate.

Comparison of the outcome of treatment of patients with clefts of the lip and palate can yield valuable pointers for discriminating between beneficial and harmful procedures. The development of a standardized rating scheme to assess the facial appearance of these patients is described. The rating scheme can be used in conjunction with conventional cephalometric analysis and dental arch evaluation. A method is described in which the nasolabial area is masked, thus reducing the influence of the surrounding facial features since it is shown that judges are influenced by general facial attractiveness. An ordinal scale has been evaluated in which four features of the nose and lip are assessed separately and in total by a panel of judges. The nasolabial profile, the nasal symmetry, the nasal form, and vermilion border were assessed using a 5-point scale. Acceptable pooled levels of reliability and reproducibility were obtained. This standardized rating system may be used to differentiate treatment outcome in patients from different treatment centers.

Adolescent↗
PubMed1991

A longitudinal study of the condition of first permanent molars in a group of adolescents with special reference to elective orthodontic tooth extraction.

The aim of this study was to investigate changes in the condition of first permanent molars over the teenage years, with special reference to adolescents who lost premolar teeth for orthodontic purposes. A total of 453 South Wales schoolchildren (219 males and 234 females) were examined at the ages of 11-12 and 19-20 years. At 11-12 years, 89.6 per cent of the cohort had all four first permanent molars, while 3.3 per cent had already lost these teeth. Of those first permanent molars present, 61.7 per cent had some caries experience. At age 19-20, 80.6 per cent of subjects retained four first permanent molars while 4.4 per cent had none. Of the first permanent molars present, 80.6 per cent had been affected by caries. In 60 per cent of the 186 subjects (75 males and 111 females) who had lost premolar teeth in the course of orthodontic treatment, a sound premolar was extracted in preference to a first permanent molar which already had evidence of dental disease. At age 19-20 years, the majority of the first permanent molars were restored and otherwise sound, though a small number which had been restored at age 11-12 years had been lost due to caries.

Adolescent↗
PubMed1990

Current cleft lip and palate management in the United Kingdom.

This is a report of a national survey into cleft management which was carried out in the spring of 1988. Responses were received from 45 cleft teams in England, Wales, Scotland and Northern Ireland. A summary of the results is presented covering aspects of neonatal care, presurgical orthopaedics, primary and secondary surgical procedures and orthodontic management. In a majority of centres treatment management is discussed at interdisciplinary combined clinics. A wide range of timings and techniques is used for both surgical and orthodontic therapy.

Age Factors↗
PubMed1990

Factors influencing the initiation of carious lesions in specific tooth surfaces over a 4-year period in children between the ages of 11-12 years and 15-16 years.

An analysis of factors influencing the initiation of carious lesions on specific tooth surfaces over a 4-year period in children between the ages of 11-12 years and 15-16 years is presented. Approximately 1000 children, resident in the County of South Glamorgan, Wales, were assessed for caries status and oral cleanliness in 1980 when aged 11-12 years and again in 1984 when aged 15-16 years. On both occasions, the children completed detailed questionnaires on dental health-related topics. Surfaces which were sound when the children were 11-12 years were identified and subsequently awarded a score of zero if they remained sound at 15-16 years or a score of one if they had developed carious lesions or had been filled. For each child, a mean mouth caries initiation score was computed for specific groups of surfaces, namely pit and fissure surfaces in posterior teeth, approximal surfaces in posterior teeth, buccal and lingual smooth surfaces of all teeth and approximal surfaces of anterior teeth. One-way analysis of variance and multiple regression techniques revealed that a number of factors had a significant influence on the initiation of caries. The factors and their level of significance varied between the surfaces. However, relatively little (less than 6 per cent) of the total variance in caries initiation score could be explained by the identified factors. Overall, more lesions developed in pit and fissure surfaces in posterior teeth than in the other surfaces included in the analyses.

Adolescent↗
PubMed1990

Factors influencing the caries experience of a group of children at the ages of 11-12 and 15-16 years: results from an ongoing epidemiological survey.

An analysis of factors influencing the caries experience of adolescents in South Wales is presented. Approximately 1000 children were assessed for caries status and oral cleanliness in 1980 when aged 11-12 years and again in 1984 when aged 15-16 years. In addition, on both occasions, the children completed detailed questionnaires on dental health-related topics. When aged 11-12 years, the observed mean DMFT, DMFS and DFS scores of the children were 4.0, 6.7 and 5.5 respectively. The corresponding scores at age 15-16 years were 6.5, 11.8 and 10.2. A preliminary analysis using conventional multiple regression techniques revealed that a number of factors had a significant influence on the caries experience of the children. The significance of the factors depended on the sex of the population subgroup, the age of the children and the particular caries index studied. However, at both ages the factors of most significance were the number of erupted teeth, total mean plaque score and the reported amount of money spent on sweets per week. A further evaluation using analysis of covariance with the number of erupted teeth and surfaces as the covariates confirmed the significant influence of the total mean plaque score and amount of money spent on sweets. In addition, both analyses indicated that toothbrushing frequency and social class had a significant influence on the caries experience of boys.

Analysis of Variance↗
PubMed1990

Traumatic injury to maxillary incisor teeth in a group of South Wales school children.

This study examines, from photographic records, the prevalence of accidental damage to maxillary incisor teeth in a group of 968 11/12-year-old South Wales school-children; 15.3% showed evidence of trauma ranging from enamel fractures or discolouration to actual loss of a tooth. Boys (19.4%) showed a higher prevalence of trauma than girls (11%). Maxillary central incisors were the most at risk from trauma, with coronal fractures being the most commonly sustained injury. Those subjects who showed evidence of trauma had an statistically (p less than 0.001) but not clinically significantly greater overjet than did those who had none. The percentage of subjects suffering trauma increased significantly with increasing overjet, but lip incompetence did not affect the prevalence of accidental damage. Though statistically unsupported due to the small numbers involved in this cohort, it appeared that the rougher nature of boys activities and their more active participation in sports were of greater importance than the magnitude of their overjet in determining whether their teeth were at risk from trauma. In contrast, it was the magnitude of the overjet which was the dominant factor in girls. Despite the wide availability of relatively simple means of restoration and, in the majority of cases, regular dental examinations, only 14.8% of traumatised teeth had received treatment at this age.

Child↗
PubMed1990

Pharyngeal flap and facial growth.

The present study addressed two questions. Does the skeletal pattern of children with cleft lip and palate who require a pharyngeal flap differ from children with similar clefts who do not? Following a pharyngeal flap does the pattern of facial development change? Skeletal form prior to pharyngeal flap was compared using cephalograms in 52 subjects with unilateral cleft lip and palate (UCLP) who subsequently received a superiorly based pharyngeal flap and 52 UCLP controls matched for sex and age. The flap group had slightly smaller maxillary length and anterior face heights and greater mandibular protrusion (p less than 0.5) before the pharyngeal flaps were done. Preoperative and five year (minimum) postoperative records were analyzed for 29 early pharyngeal flap cases and 29 matched controls. Subsequent growth demonstrated some assimilation of the flap group with the controls, but repeated measures analysis of variance failed to identify any important differences in growth after pharyngeal flap, suggesting that the superiorly based pharyngeal flap carries no systematic risk of interference with facial growth.

Adolescent↗