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Biomedical subjects

T L Watts

Publications and source records attributed to T L Watts.

At least 37 records · Page 2Linked to original sources
PubMed1995

Coenzyme Q10 and periodontal treatment: is there any beneficial effect?

Many dentists have been surprised by recent media claims of periodontal benefits with a purportedly revolutionary dietary supplement. The research literature on coenzyme Q10's periodontal effects does not extend to the international English language dental literature, which perhaps explains the surprise. A review of the available literature does not give any ground for the claims made, and selected papers are discussed to show that there is actually some evidence that coenzyme Q10 has no place in periodontal treatment.

Clinical Trials as Topic↗
PubMed1995

Initial study of periodontal status in non-insulin-dependent diabetics in Mauritius.

OBJECTIVES: Investigation of Mauritian non-insulin diabetic periodontal health. METHODS: In Port Louis, the capital of Mauritius, 24 patients with non-insulin-dependent diabetes mellitus were matched by age with 24 controls. Because matching was incomplete for gender and race, the groups were treated as independent for data analysis. Operator-blind scores were recorded for the presence of plaque, bleeding on probing, probing depth, recession and probing attachment level. RESULTS: When variations in plaque and age were taken into account, there was a significant difference in probing attachment level between the groups (diabetic mean = 4.16 mm, control mean = 3.09 mm), and an effect of gender on gingival bleeding which may relate to tobacco smoking. CONCLUSION: In an isolated community with a 13% prevalence of NIDDM, this study confirms previous periodontal findings regarding the effect of the disease.

Adult↗
PubMed1995

Periodontal disease activity: a development strategy for its investigation by means of accurate 3-dimensional clinical measurement.

The central problem in all previous approaches to clinical assessment of periodontal disease activity is the use of unidimensional measurement, which implies a number of unjustifiable assumptions. In addition, the use of unidimensional probing measurement has established that there are several distinct problems of validity and reliability in currently available techniques. The present paper begins with an analysis of these matters, leading to an approach to accurate clinical measurement of periodontitis in 3 dimensions, with the possibility of future development of a valid system for assessing the nature of disease activity.

Connective Tissue↗
PubMed1995

Single-blind studies of the effects of improved periodontal health on metabolic control in type 1 diabetes mellitus.

Uncontrolled studies have suggested a beneficial effect of periodontal treatment on metabolic control of insulin-dependent diabetes mellitus (IDDM). We therefore conducted controlled single-blind studies, using current metabolic status indicators in IDDM subjects free of significant complications other than periodontal diseases. In the 1st study, 41 IDDM subjects with gingivitis and early periodontitis were randomly assigned to treatment (oral hygiene and scaling) or control groups. The study was completed by 16 experimental and 15 control subjects. Reassessment after 2 months showed a Hawthorne effect in the control group, and no difference between groups. However, further analysis showed a relationship between individual metabolic control variation and gingival inflammation. A 2nd study enrolled 23 IDDM subjects with advanced periodontitis, who were randomised to treatment (full initial therapy including root planning) or control groups. Only 1 subject failed to complete the study, owing to illness. In this study, a significant response to periodontal treatment was not accompanied by any improvement in metabolic control. These results support the concept that the effect of metabolic control may be predominant in the relationship between IDDM and periodontal health.

Adolescent↗
PubMed1995

Psychological mood of regular dental attenders in relation to oral hygiene behaviour and gingival health.

This study examined the relationship between psychological mood, stress and oral hygiene behaviour in a group of 51 regular dental attenders. Subjects brought a saliva sample for cortisol radioimmunoassay, completed the Hospital Anxiety and Depression (HAD) Scale, were assessed for plaque and gingivitis, and were then instructed in toothbrushing. 5 weeks later, 47 subjects were given a full repeat examination. There was a slight reduction in plaque and gingivitis scores, but no change in mood as assessed by HAD Scale and salivary cortisol concentration. Mean anxiety scores were associated with gingivitis level, and mean depression scores with plaque. Neither mood nor cortisol were predictors of subsequent change in plaque or gingivitis.

Adult↗
PubMed1995

Periodontal inflammation and attachment loss: a critical problem for biological studies.

BACKGROUND: In biological studies of periodontitis, there has been long-standing confusion between the ubiquitous phenomena of inflammation and the essential criterion of attachment loss. This is partly attributable to inadequate methods of clinical measurement, but seems also to be a consequence of an unproven and usually unstated assumption that the same biological processes underlie both inflammation and attachment loss. Developments in unidimensional clinical probing methods have helped in studies of periodontal treatment. However, such methods are intrinsically unsuitable in studies of periodontal diseases, and may have given them a false sense of security. the confusion has been compounded by inappropriate use of statistical techniques in an attempt to solve problems which do not arise from mathematical models but are intrinsic to measurement methods. OBJECTIVE: This paper is a clinician's attempt to state the current difficulties and suggest some ways forward, including the development of three-dimensional measurement, non-invasive probing, and several objectives for biochemical, microbiological and immunological research.

Data Interpretation, Statistical↗
PubMed1993

A skin window study of neutrophil migration in subjects with localized juvenile periodontitis.

This study investigated the effect of a chemoattractant, N-formyl-methionyl-leucyl-phenylalanine (FMLP), upon skin window migration of neutrophils into filters in 5 patients with a history of localized juvenile periodontitis (LJP) and 8 controls. On 2 occasions, each subject had 2 superficial skin abrasions made on the inner aspect of the forearm. Initial periodontal treatment was carried out on the disease group between the visits. On one skin window filters were placed that were soaked in physiological saline, and on the other filters soaked with FMLP. Leading fronts and cell densities were measured in each filter. At visit 1, LJP subjects had significantly lower leading fronts and cell densities. At visit 2, the differences were insignificant. The leading fronts for the LJP group were significantly improved on the second visit. No difference was observed between saline and FMLP. The findings of this study indicate that neutrophil migration is reduced in LJP patients where treatment is not involved, and that FMLP has no effect on neutrophil migration from the skin windows under the conditions of this study.

Adult↗
PubMed1990

An in vivo study of neutrophil locomotion in relation to periodontal disease status and local chlorhexidine.

Neutrophil migration from skin window abrasions was studied in 10 patients with no history of periodontitis, 10 with localised juvenile or post-juvenile periodontitis, and 10 with chronic adult periodontitis. Filters contained either saline or chlorhexidine (0.002% or 0.02%). The leading front was measured in filters placed for 30 min after cell migration had been established for 2 h. Subjects in the juvenile/post juvenile group showed a reduced range of migration distances, but were still within the normal range when compared with the other 2 groups. Chlorhexidine at 0.002% tended to increase leading front distances, and 0.02% to decrease them. We conclude that: 1) migrating neutrophils in vivo may move less far in patients with a history of juvenile periodontitis; 2) chlorhexidine may inhibit cell migration, possibly decreasing the host response in vivo if applied at current therapeutic concentrations.

Adolescent↗
PubMed1989

Effects of chlorhexidine solution on neutrophil locomotion in vitro.

The aim of this study was to ascertain the effect of low concentrations of chlorhexidine on the locomotor behaviour of neutrophils. A special feature was the use of a direct test of chemotaxis. Neutrophils recovered from peripheral blood of healthy adult volunteers were tested for chemokinesis and chemotaxis in the presence of chlorhexidine. A moderate dose-related direct response was observed in respect of both these parameters. It was also apparent that increasing concentrations of the drug inhibited a greater proportion of cells, so that there was total immobility at 0.2 per cent and many cells appeared lysed.

Adult↗
PubMed1989

Probing site configuration in patients with untreated periodontitis. A study of horizontal positional error.

This study examined the morphology of 487 probing sites in patients with untreated periodontitis, using a constant force probe (0.25 N, 0.5 mm) and flexible stent with guide grooves, at 3 adjacent points per site, 6 sites per tooth. Sites were classified into 9 configuration types according to the relationship of the 3 adjacent points. Duplicate measurements were made and sites were analysed with special reference to whether a slight horizontal movement was likely at the second examination. 60% of individual point probing measurements were exactly reproduced, but only 23% of site configurations. 65% of configuration change was accountable on the basis of slight horizontal shift of the probe. Only 13% of configurations required the postulate of other forms of probing error. These results suggest that probing reproducibility is not always an indication of site reproducibility, and that the variation of probe position in the transverse plane is an important source of probing error, even when a stent is used.

Humans↗
PubMed1989

Visual and tactile observational error: comparative probing reliability with recession and cementoenamel junction measurements.

Probing error may arise from several sources, including visual observations and tactile detection of the cementoenamel junction (CEJ). This study examined two types of probe scale in relation to measurements of recession and CEJ from a flexible stent, and two types of probe design in addition, in relation to CEJ detection. 492 sites were studied in six patients with untreated periodontitis. Following stent construction, patients attended for measurement of recession and probing depth. This was repeated after 1 h, and then calculus was scaled in the vicinity of the CEJ. One week later, patients attended for CEJ measurements, which were similarly repeated. Measurements with an offset scale (between marks) were more reproducible in general, though no significant difference was detected between recession scores. The most reproducible detection of the CEJ was with a modified Cross calculus probe with an offset scale. A curious feature of the results was a bias affecting 9% of the recession measurements. It is possible that edematous enlargement of the gingiva occurred after the first measurement of probing depth, and was occasionally sufficient to alter the recession score.

Bias↗
PubMed1989

The effect of 1% metronidazole gel in routine maintenance of persistent furcation involvement in human beings.

The aim of this study was to test adjunctive insertion of 1% metronidazole gel into furcation areas during periodontal maintenance. Ten patients were selected with paired, contralateral, Class II or III furcation involvements that also bled on constant force probing. Bleeding on probing (BOP) and gingival crevicular fluid (GCF) were measured as experimental variables. Plaque was assessed by dark-field microscopy (DFM). Following routine subgingival maintenance of these sites, a syringe was used to insert metronidazole or placebo gels into the furcations. Sites were re-examined 1 and 3 months after baseline. There was little change in either BOP or GCF. Marked longitudinal changes were found by DFM for both experimental and control sites. Experimental sites were not significantly different when compared with controls at the 5% level of probability.

Adult↗
PubMed1988

Patterns of oviducal motility in the cow during the oestrous cycle.

Microtransducers sensitive to changes in internal diameter were chronically implanted in the oviducts of 5 dairy cows. Motility patterns were recorded throughout 9 oestrous cycles. Cyclic variations in patterns of motility were observed and compared with circulating concentrations of plasma progesterone. Luteal-phase motility patterns were of low amplitude and frequency. The frequency and amplitude of motility increased 3-5 days before behavioural oestrus. This activity consisted primarily of longitudinal muscle contractions, with an interspacing of circular muscle activity occurring during oestrus. Patterns of activity after oestrus were similar to those before oestrus, with activity decreasing 3-5 days after oestrus. Transducers implanted bilaterally in 2 animals permitted observation of asynchronous patterns between right and left oviducts. Preliminary data suggested a higher level of activity in the oviduct ipsilateral to the active ovary. These variations may be due to a local effect, possibly mediated by the functional ovary or the ovum.

Animals↗
PubMed1988

Upper anterior tooth mobility. Selected associations in untreated periodontitis.

The relationship between buccolingual tooth mobility (TM) and other clinical parameters was studied in 124 upper anterior teeth in 21 patients with untreated periodontitis. Periapical long-cone radiographs were available for 74 teeth in the same population. TM was measured with Mühlemann's macroperiodontometer. Probing depths, attachment levels and bleeding were measured with a constant force probe. Bone levels were estimated from radiographs. Presence of occlusal contact was noted in the intercuspal position and excursive movements of the mandible. Attachment levels showed the highest correlation with TM, and radiographically estimated bone support was the next highest. Results varied according to tooth type: the attachment level of the lateral incisors showed the highest correlation with TM, while probing depths and proximal bone support showed lower associations with TM in all cases. In this population, no association was detected between the presence of occlusal contact and TM, or between inflammation and TM. Multiple and partial correlation analysis indicated that probing attachment level was the most important correlate of tooth mobility.

Adult↗
PubMed1987

Short-term effect of Keyes' approach to periodontal therapy compared with modified Widman flap surgery.

Keyes' method of non-surgical therapy was compared with modified Widman flap surgery in 9 patients with symmetrical periodontal disease. Following an initial oral hygiene programme, baseline measurements were recorded and paired contralateral areas were subjected randomly to the 2 techniques. 42 teeth receiving surgery were compared with 40 treated by Keyes' method. 6 sites per tooth were scored immediately prior to therapy and 3 months later, using a constant force probe with onlays. Consistent data were recorded for the 6 separate sites, which showed no baseline difference between treatments, slightly greater recession with surgery at 3 months, but no difference between treatments in probing depth and attachment levels. Mean data for individual patients showed similar consistency. Probing depth in deep sites was reduced slightly more with surgery, and there were no differences in bleeding on probing at 3 months. Both techniques gave marked improvements in health. Surprisingly, only 2 subjects preferred Keyes' technique of mechanical therapy, 6 preferred surgery, and 1 had no preference.

Adult↗
PubMed1985

Response and fertility of dairy heifers following injection with prostaglandin F(2alpha) during early, middle or late diestrus.

After an observed estrus, 250 dairy heifers were injected once with 25 mg of PGF(2alpha) either on cycle days 5 through 7 (E), 8 through 11 (M) or 12 through 15 (L). For five days after the PGF(2alpha) injection, heifers were inseminated at about 12 h after estrus was first observed. Observed estrual response rates were 43.0%, 83.6% and 100% for E, M and L, respectively. Average time from PGF(2alpha) to observation of estrus for E, M and L was 59, 70 and 72 h. Conception rates for heifers responding to PGF(2alpha) were 56.8%, 62.1% and 78.3% for E, M and L, respectively. Based on blood samples drawn at the time of PGF(2alpha) injection, progesterone concentration was significantly correlated with response rate but not with conception rate. When compared with M and L, E had a significantly lower response rate and conception rate as well as a shorter period between injection of PGF(2alpha) and observation of estrus.

Journal Article↗
PubMed1983

Subcutaneous tissue response in rats to an aluminoborate cement.

In the interests of producing an improved periodontal dressing material, adhesive cements are under consideration. A new glass ionomer system--aluminoborates--shows some potential in this respect, and a relatively soluble formulation was chosen for a simple biological test in rats, by means of implantation in polypropylene tubes. As a positive control, the widely used aluminosilicate cement Aspa was employed, and empty tubes were used as negative controls. A simple scoring system using interval measurements was employed, and showed no difference at the 5% level between the experimental cement and either control, although slight differences were discernible between controls. The study also indicated that the side of a filled tube is not the best control for assessment of reaction at tube ends.

Animals↗