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P A Heasman

Publications and source records attributed to P A Heasman.

At least 19 recordsLinked to original sources

Effect of brushing force and time on plaque removal using a powered toothbrush.

OBJECTIVES: Primary objective - To determine the effect of varying brushing forces and brushing times upon the plaque-removing efficacy of a powered toothbrush. Secondary objective - to determine the optimum combination of brushing force and time for plaque removal. MATERIAL AND METHODS: This randomised, single-blind, 16-cell, cross-over trial compared the efficacy of plaque removal of a powered toothbrush (PTB) used with four brushing forces (75, 150, 225 and 300 g) and over four brushing times (30, 60, 120 and 180 s). Twelve volunteers (18-30 years) were recruited and trained to use the Philips/Jordan Sensiflex 2000 PTB, which was modified so that specified forces and times could be recorded. Each subject was asked to abstain from all oral hygiene procedures for 24 hs prior to each brushing event, to allow plaque accumulation. Plaque was recorded using a modified Quigley & Hein index (PI) at six points per tooth before and after each episode of brushing, and the differences in the means (pre- to postbrushing) were compared. Three-way anova was undertaken to compare differences between plaque-removing efficacy for the 16 combinations of force and time. Subjects, brushing time and brushing force were used as fixed effects within the analysis. RESULTS: All 12 subjects participating completed the 16 combinations of force and time over which plaque removal was assessed. Statistically significant differences in PI reductions were found between different brushing times and forces over all tooth surfaces (p<0.001). The interaction of varying brushing force and brushing time was significant for full mouth (FM) and interproximal (IP) sites (p<0.03). No statistical significance was demonstrated for smooth surface (SS) sites, nor was it detected for the interaction of subjects with brushing force or subjects with brushing time (p>0.05). CONCLUSION: We conclude that brushing time and brushing force have significant effects upon the level of plaque removal by a PTB, and at 120 s brushing time the improvement in plaque removal with forces in excess of 150 g was negligible.

Adult↗

Testing the efficacy of 2 prototype brush heads for a powered toothbrush: refining the model.

OBJECTIVES: To compare 2 prototype powered toothbrush (PTB) heads (A, B) to a marketed head (Sensiflex 2000) for plaque removing efficacy on the Philips/Jordan HX2550 PTB. MATERIALS AND METHODS: A 2-week, 3-group, single-blind trial recruited 78 volunteers (18-25). Plaque indices (PIs) were recorded at screening and 14 days later at baseline. Subjects were stratified (gender and PI) and then asked to abstain from oral hygiene measures for 48 h. A supervised episode of brushing with the allocated PTB head followed. Subjects then used the PTBs at home for the next 12 days before being asked to abstain from all oral hygiene measures for another 48 h prior to a second supervised brushing episode. Plaque was scored using a new modification of the Quigley & Hein Index (PI) at full mouth (FM), interproximal (IP) and smooth surfaces (SS). PIs were recorded before and after the supervised brushing episodes to enable the means of the within subject differences (pre- to post-brushing) to be compared between groups (ANOVA/t-tests). RESULTS: There were no significant differences in PI between groups at baseline or prior to the supervised brushings (p>0.05). Highly significant, mean reductions in PIs (approximately 1/2 of one PI unit) were observed for design B compared with the Sensiflex 2000 at FM and IP sites (p<0.0001) for both supervised brushing episodes. A significant reduction in PI at SS was seen only after the first brushing episode (p=0.0004). For design A, PI reductions were consistently greater than those for the Sensiflex 2000 but differences were only significant at the p<0.05 level. CONCLUSION: It is concluded that this model of clinical trial has sufficient power to demonstrate clinical superiority with respect to plaque removal for PTBs and can be used for testing one or more prototype designs of brush heads.

Adolescent↗

A clinical evaluation of a novel data logger to determine compliance with the use of powered toothbrushes.

OBJECTIVES: The primary objective of this study was to evaluate the viability of an electronic data logger to record the brushing episodes of patients receiving standardised oral hygiene instructions. The secondary objective was to estimate the compliance of a group of patients diagnosed with chronic periodontal disease with brushing time instructions for the daily use of a powered toothbrush over a 2-month period. MATERIAL AND METHODS: 17 modified Philips Jordan Sensiflex 2000 powered toothbrushes (PTBs) were provided to patients (32-67 years) attending for non-surgical management of chronic periodontal disease. The PTBs incorporated an electronic data logger which recorded, for each individual brushing event: the length of time the brush was used (identifying the brushing speed setting); the maximum, minimum and average current during operation; and the time spent charging in between two consecutive brushing events. The patients were given detailed instructions with the PTB and were told to use it for 2 min each morning and 2 min in the evening. The patients returned for non-surgical management over two visits prior to reinforcement of the oral hygiene instructions 1 month after PTB allocation. Subjects were asked to complete a simple brushing diary to record their use of the toothbrush on a daily basis. After 2 months of using the PTBs at home, the brushes and diaries were collected and the data downloaded from the data loggers. RESULTS: Of the 17 data loggers allocated, two recorded no information and two subjects did not return for the follow-up appointments. The data from the remaining 13 data loggers were evaluated for level of compliance. An event of brushing between 120 and 130 s was considered to be compliant, one of between 90 and 120 or 130-150 s was partially compliant and brushing for < 90 s or > 150 s was recorded as non-compliant. Percentage compliance for all the events (2087 recordings) was 34%, partial- and non-compliance were calculated as: 18%; 48% of events, respectively. CONCLUSION: This data logger has provided previously unrecorded data on the brushing times for a group of patients using a powered toothbrush at home during non-surgical management of chronic periodontal disease. The data suggested that almost half (48%) of the brushing events recorded by the data loggers were greater than 30 s above or below the instructed brushing time.

Adult↗

Efficacy of a prototype brush head for a powered toothbrush. A multicentre study.

PRIMARY OBJECTIVE: To evaluate a multicentre clinical trial design for testing powered toothbrushes. SECONDARY OBJECTIVE: To compare the efficacy of a prototype brush head (N2.3) for the Philips Jordan Sensiflex 2000 powered toothbrush (PTB) to that of Braun Oral-B D15 PTB in removing dental plaque MATERIAL AND METHODS: 137 volunteers (ages 18-25 years) were recruited to this 3-centre, 2-week, 2-group, 2-treatment, single-blind trial. Plaque was recorded at screening and again 14 days later at baseline. Stratification of subjects, for gender and screening PI, occurred at baseline. Subjects were then asked to abstain from all oral hygiene measures for 48 h followed by a supervised episode of brushing for 3 min with the allocated PTB. The allocated PTB was used at home for the next 12 days before a second abstinence from all oral hygiene measures for the 48 h prior to a second supervised brushing episode. Plaque levels were scored using a modification of the Quigley & Hein plaque index (PI) at full mouth (FM), interproximal (IP) and smooth surfaces (SS). To enable the means of the within subject differences (pre to postbrushing) to be compared between groups PIs were recorded before and after the supervised brushing episodes, differences between centres, groups and visits were examined. RESULTS: No significant differences in PI between groups at screening, baseline or prior to the supervised brushings were detected (P > 0.05 anova). The results of the analysis of variance showed there to be a highly significant difference (P < 0.001) between brushing groups, but, significant differences between centres (P < 0.001) and a significant interaction effect between centre and brushing group (P < 0.001) was also detected. Therefore the difference between groups was not present at all three centres. Further examination of the single centre data showed there to be greater levels of plaque removed by the N2.3 compared to the D15 (FM reduction in PI 1.95 vs. 1.13, respectively) at centre 3 in contrast to the other two centres where no difference was detected. The precise reason for these differences could not be established. CONCLUSIONS: A multicentre study design is applicable for evaluating PTBs but a minimum of 3 centres should be included so that differences between centres can be identified. The prototype brush head N2.3 for the Philips Jordan Sensiflex 2000 PTB has comparable plaque removal efficacy to the Braun Oral-B D15 PTB at FM, IP and SS sites.

Adolescent↗

Clinical evidence for the efficacy and safety of powered toothbrushes.

Powered toothbrushes are becoming increasingly popular among the general population, and there are many models on the market from which to choose. The design of these toothbrushes is changing constantly, as one would expect with a developing and expanding market, and from the dental professional's standpoint, it is difficult to evaluate products from the literature simply because the designs of clinical trials for powered toothbrushes are so varied. For example, the cohort recruited for testing the products is seldom the same from one study to the next. The aim of this paper is to provide a brief overview of the findings from some of the more contemporary trials of powered toothbrushes and to examine some of the factors that might have an effect on the observations and outcomes.

Clinical Trials as Topic↗

Local delivery of chlorhexidine gluconate (PerioChip) in periodontal maintenance patients.

AIM: The aim of this randomised, split-mouth, single-blind study was to determine the efficacy of controlled-release delivery of chlorhexidine gluconate 2.5 mg (PerioChip) in patients with residual bleeding pockets (>5 mm) at least 3 months following oral hygiene and root debridement phase therapy. MATERIAL AND METHODS: 26 patients (non-smokers) were screened and potential study sites identified. Clinical parameters recorded at baseline and all subsequent visits were plaque index (PI), pocket probing depth (PPD), bleeding index (BI) and clinical attachment level (CAL). All study sites were debrided using ultrasonic instrumentation. PerioChips (PC) were placed in the selected sites of two quadrants (left or right) whilst identified sites in the remaining quadrants were left without adjunctive antimicrobial treatment. Clinical measurements were made at follow-up visits after 1, 3 and 6 months. Mean changes from baseline in PPD, BI and CAL were calculated with the patient as the experimental unit and comparability between the treatments was determined using t-tests. RESULTS: At baseline there were no significant differences between PC and control sites for mean PI, PD, BI or CAL. The mean (SE) reductions in PPD for PC and control treatments were: 0.47 (0.1), 0.46 (0.1); 0.76 (0.1), 0.55 (0.1); 0.78 (0.1), 0.45 (0.1) for months 1, 3 and 6 respectively. Only at month 6 did the difference between treatments approach statistical significance (p=0.06). Mean (SE) reductions in CAL over the same periods were: 0.17 (0.1), 0.04 (0.08); 0.38 (0.1), 0.21 (0.1); 0.43 (0.1), 0.15 (0.09) p=0.048. Mean (SE) reduction in BI between PC and control treatments only reached statistical significance at 6 months: 1.08 (0.1), 0.59 (0.1) p=0.05. CONCLUSION: These data suggest that PerioChip is beneficial for patients on maintenance therapy although the benefit is not apparent until 6 months after placement.

Adult↗

Influence of a controlled pressure system on toothbrushing behavior.

The use of excessive brushing force has been shown to be a major cause of gingival abrasion. To aid in preventing over-vigorous brushing, the Philips/Jordan electric toothbrush incorporates a Controlled Pressure system (CPS) that causes the brush head to flex back when a toothbrushing force (TBF) in excess of a pre-determined threshold is exerted against the teeth or soft tissues. Two studies (I/II) were conducted to determine whether this mechanical feedback system is sufficiently sensitive to enable users to control their brushing behavior. In Study I, the learning pattern of brushing behavior as a response to the feedback system was evaluated. Seventeen subjects were asked to brush their teeth under observation at least twice a day for a two-week period. During these observations, the number of clicks, as well as the time the brush was pushed "through the click" were recorded. Ten of seventeen volunteers demonstrated a clear learning behavior; the mean number of clicks/minute (for all subjects) was reduced from 10 to 4 after 10 sessions of brushing, and then to 2 or 3 clicks at the end of two weeks. In Study II, 46 subjects used the electric toothbrush with the CPS click force set at various levels between 150-420 g (at 30 g intervals). After a 4-week learning period, the mean TBF was determined in each subject. TBF was most strongly influenced at pre-set click forces between 180 and 270 g. The mean TBF was lowest (about 80 g) when the threshold was set at 210 or 240 g; it then increased (to about 130-140 g TBF) both for smaller and larger values of the threshold setting. Hence, both studies indicate that the Controlled Pressure system is a functional feature that can be used to control the habitual brushing force in a learning period of less than 2 weeks.

Adult↗

A comparative study of two powered toothbrushes and one manual toothbrush in young adults.

The aim of this 3-group, 3-treatment, single-blind, parallel group study was to evaluate and compare the efficacies of the Philips/Jordan HP735 powered toothbrush, the Braun/Oral-B D7 powered toothbrush, and the Oral-B Advantage B35 manual toothbrush in young adults (18-25 years). Full mouth mean (SD) modified Turesky Plaque Index (PI) and the Löe & Silness Gingival Index (GI) were recorded at baseline. After 24 hours abstinence from oral hygiene, the PI was recorded and each subject was given one of the test brushes with detailed instructions for use. Each subject then brushed under supervision for 90 seconds, during which time mean (SD) toothbrushing forces (TBF) were recorded. PIs were recorded immediately after brushing, and the subjects were then discharged for 6 weeks to use the allocated toothbrush at home. After 6 weeks, PI, GI and TBF were again recorded. There were no significant differences (ANOVA) for PI and GI between groups at baseline, or for PI following brushing at 24 hours. After 6 weeks, the powered brushes produced lower mean PI (SD) scores than the manual brushes, but the differences were significant only at interproximal sites. Mean GI scores for the HP735 group were similar at baseline and at 6 weeks, although for the other brushes the GI scores actually increased over this period. Mean (SD) TBF (grams/force) at baseline and 6 weeks, respectively, for the brushes were; HP735 233 (205), D7 159 (58), B35 279 (122) (p = 0.026): HP735 194 (86), D7 141 (57), B35 297 (113) (p = 0.0001). The within-group variability for the HP735 TBF reduced considerably over 6 weeks, which is possibly because of the click-force threshold feature of this brush.

Adolescent↗

Anticalculus agents.

Most dentifrices and some mouthrinses now contain 1 or more active anticalculus agents to achieve so-called tartar control. The aim of this article is to review the research associated with the development of anticalculus agents and to evaluate in some detail, the efficacy of those agents which are currently available in dentifrice products.

Dental Calculus↗

Testing the efficacy of plaque removal of a prototype brush head for a powered toothbrush.

BACKGROUND/AIMS: The principal aim of the study was to compare the efficacy of a powered toothbrush (PTB) prototype (B) brush head in removing dental plaque to the relative efficacy of a marketed model (A). METHOD: A 12-week, 2-group, 2-treatment, double-blind trial of 2, two-brush heads (with the same power unit) recruited 62 volunteers (18-25 years) who were non-clinical university students. After a screening visit, 31 subjects were allocated to each of groups A and B at baseline with stratification according to gender and plaque index. After 48 h of plaque growth, subjects underwent a timed and supervised brushing episode with the allocated PTB (visit 1). Subjects then used the PTBs at home for 12 days before being recalled (visit 2) and asked again to abstain from all oral hygiene measures for 48 h. Supervised brushing was repeated (visit 3) before the subjects were dismissed for a further 10-week, unsupervised period of home use of the PTBs. The sequence of visits (2 and 3) was then repeated at visits 4 and 5. RESULTS: The sole outcome variable was plaque which was scored at all visits using the modified Quigley & Hein Index (PI) at full mouth (FM), interproximal (IP) and smooth surfaces (S). At visits 1, 3 and 5, the PI was recorded both before and after supervised brushing. There were no significant differences in PI between the brushing groups at baseline, visit 1, visit 2 or visit 5 (2 sided t-test). At visit 3, the prototype achieved significantly lower PIs than the marketed PTB brush head for IP (and FM) surfaces, this difference was most apparent on posterior tooth surfaces. For within-group changes, PIs at visit 2 were significantly lower than those at baseline (paired t-test), an observation which may be attributable to the improved cleaning and 'novelty effect' of a PTB. The PIs at visit 5 were significantly higher than the baseline values (paired t test) and this may be accountable to an element of Hawthorne effect and/or, a fall off in compliance over the entire 12 weeks. CONCLUSION: We conclude that this in vivo model is appropriate for testing the efficacy of PTB prototypes but only over a 2-week period, as the inter-group differences were not maintained over the full 12 weeks of the trial.

Adolescent↗

Association of interleukin-1 gene polymorphisms with early-onset periodontitis.

BACKGROUND, AIMS: Early-onset periodontal diseases (EOP) are a group of inflammatory disorders characterised by a rapid rate of periodontal tissue destruction, in young individuals who are otherwise healthy. There is now substantial evidence to suggest that genetic factors play a rôle in the pathogenesis of EOP but the precise nature of these factors remains unclear. Polymorphisms in cytokine genes which may underpin inter-individual differences in cytokine synthesis and secretion have been associated with other diseases which have an inflammatory pathogenesis, including chronic adult periodontal disease (CAPD). METHOD: We therefore investigated the frequency of polymorphisms in the genes encoding interleukin-1 beta (IL-1 beta) and its receptor antagonist (IL-1RA) in 70 EOP patients, including a subgroup of 21 localised EOP (L-EOP) patients and 72 periodontally healthy controls. All subjects were of Caucasian heritage and systemically healthy. A single nucleotide polymorphism (SNP) in exon 5 of the IL-1 beta gene (IL-1 beta+ 3953) was analysed by amplifying the polymorphic region using PCR, followed by restriction digestion with Taq1 and gel electrophoresis. RESULTS: The frequency of IL-1 beta genotypes homozygous for allele 1 (corresponding to the presence of a restriction site) of the IL-1 beta+3953 SNP was found to be significantly increased in EOP patients (chi2 test, p = 0.025). Upon stratification for smoking status a significant difference was found in the IL-1 beta genotype distribution between EOP smokers compared to control smokers (F-exact test, p = 0.02), but not between EOP non-smokers and control non-smokers. The IL-1 beta 1/1 genotype occurred at a higher frequency in EOP smokers (odds ratio = 4.9) compared to control smokers. A variable number tandem repeat polymorphism (VNTR) in intron 2 of the IL-IRA gene was analysed by amplifying the polymorphic region using PCR and fragment size analysis by gel electrophoresis. There was no evidence for an association of an IL-1RA genotype with EOP. However the combination of IL-1 beta allele 1 and IL-IRA allele 1 (corresponding to 4 repeats) was associated with EOP (Clump, p = 0.01). CONCLUSIONS: These findings suggest that an IL-1 beta genotype in combination with smoking, and a combined IL-1 beta and IL-1RA genotype are risk factors for EOP and support a role for genetic and environmental factors in susceptibility to EOP.

Adolescent↗

Dinucleotide repeat polymorphism in the interleukin-10 gene promoter (IL-10.G) and genetic susceptibility to early-onset periodontal disease.

Emerging evidence suggests that certain genetic polymorphisms are associated with various sub-groups of early-onset periodontal diseases (EOP). We determined the genotype with respect to a (CA)n dinucleotide repeat polymorphism in the promoter region of the interleukin-10 gene (IL-10.G) in 72 patients with EOP and in 73 healthy individuals in order to test for possible disease associations. Some differences between the frequency of individual IL.10.G alleles in the patients groups as compared to the healthy controls were detected. For example the frequency of the IL-10.G9 allele in a clinical sub-group of the EOP patients with localised disease (L-EOP, n = 21) was 64.3% as compared to 41.8% in the controls. However, statistical analysis (Monte Carlo simulation) revealed that the differences in IL-10.G allele distribution between the healthy controls and both the EOP group and the L-EOP group were not statistically significant. We conclude that this study provides no evidence for a role of IL-10.G alleles in genetic susceptibility to EOP.

Age of Onset↗

A comparative study of the Philips HP 735, Braun/Oral B D7 and the Oral B 35 Advantage toothbrushes.

The aim of this 3-group, 3-treatment, single-blind, parallel group study was to evaluate and compare the efficacies of the Philips/Jordan HP 735 powered toothbrush, the Braun/Oral B D7 powered toothbrush and the Oral B Advantage B35 manual toothbrush in a cohort of 75 young adults (18-25 years). Following an appointment for screening, full mouth mean (+/-sd) modified Turesky plaque index (PI) and Löe & Silness gingival index (GI) were recorded at baseline. After 24 h abstinence from all oral hygiene measures, PI was recorded and each subject was given one of the test brushes with detailed instructions for use. The subject then brushed under supervision for 90 s, during which time mean (+/-sd) toothbrushing forces (TBF) were recorded. PI were recorded immediately after supervised brushing and the subjects were then discharged for 6 weeks to use the allocated toothbrush at home. After 6 weeks, PI, GI and TBF were again recorded. Comparisons between the brushing groups for all parameters, at baseline, 24 h and 6 weeks were tested using ANCOVA. There were no significant differences for PI and GI between groups at baseline, or for PI following supervised brushing at 24 h. After 6 weeks subjects using the powered brushes had lower mean PI (+/-sd) scores than those using manual brushes but the differences were significant only at interproximal sites; HP 735 1.44 (0.52), D7 1.44 (0.53), B35 1.75 (0.51) (p=0.05). At 6 weeks, mean (+/-sd) GI were; HP 735 1.49 (0.21), D7 1.61 (0.21), B35 1.64 (0.22) (p=0.033). Mean GI scores for the HP 735 group were similar at baseline and at 6 weeks although for the other brushes, the GI scores actually increased over this period. Mean (+/-sd) TBF (grammes/force) at baseline and 6 weeks respectively for the brushes were; HP 735 233 (205), D7 159 (58), B35 279 (122) (p=0.026): HP 735 194 (86), D7 141 (57), B35 297 (113) (p=0.0001). The within-group variability for the HP 735 TBF reduced considerably over 6 weeks, a likely consequence of the click-force threshold feature of this brush.

Adolescent↗

Powered toothbrushes: a review of clinical trials.

There is now a vast range of powered toothbrushes (PTBs) available on the market and the efficacy of each product is usually determined in one, or a series of controlled clinical trials. This article reviews briefly the design of PTBs, some of the proposed indications for their use, and the principal observations from published studies of these products. The important issues regarding the regulation and design of trials involving PTBs are discussed and some recommendations are proposed with a view to developing a more structured approach to testing these products.

Benchmarking↗

In vitro studies of lymphocyte apoptosis induced by the periodontal pathogen Porphyromonas gingivalis.

Apoptosis has a physiological role in lymphocyte development and function serving to remove self-reactive T-cells in the thymus as well as activated peripheral T-cells when they are no longer required in the immune response. Evidence from the study of several pathogenic bacteria indicate that induction of premature cell death by apoptosis may be an important pathogenic mechanism promoting infection, inflammation and concomitant disease. In this paper we demonstrate that cultures of the periodontal pathogen Porphyromonas gingivalis (P. gingivalis) promote lymphocyte apoptosis in peripheral blood mononuclear cells (PBMC). We have used assays designed to investigate the different molecular and cellular changes associated with apoptosis. Thus flow cytometry revealed that whole cultures of P. gingivalis promoted cell shrinkage in the lymphocyte fraction of PBMC and analysis of hypodiploidy confirmed that the cellular changes were associated with nuclear changes characteristic of apoptosis. We also found that apoptosis was promoted in PBMC exposed to both whole P. gingivalis cultures and culture supernatant but not washed bacterial cells; this indicates that molecule(s) secreted into the medium were responsible for this activity and not a factor intrinsic to the bacterial cell. Furthermore heat treatment has no effect on the ability of P. gingivalis cultures to induce lymphocyte apoptosis. In summary, a soluble heat stable component of the supernatant from P. gingivalis cultures promotes lymphocyte apoptosis. These data establish the principle that bacteria-induced apoptosis may be an important feature of the pathogenesis of periodontal disease.

Apoptosis↗

Progression and treatment of chronic adult periodontitis.

BACKGROUND: The periodontal status of 41 medically healthy adults with untreated chronic periodontitis was monitored before and after scaling and root planing (SRP). METHODS: During a 6-month pretreatment phase, clinical measurements, digital subtraction radiography (DSR) analysis of alveolar bone, and measurement of gingival crevicular fluid (GCF) prostaglandin E2 (PGE2) levels were undertaken. SRP was provided during a 1-month treatment phase. Clinical, radiographic, and biochemical analyses were repeated in a 6-month post-treatment healing period. RESULTS: Pretreatment: no clinically significant changes in mean plaque indices (PI), probing depths (PD), bleeding on probing (BOP), or relative clinical attachment levels (CAL) were detected (P>0.05). DSR revealed small but statistically significant bone height (0.04 mm) and mass (0.97 mg) loss (P<0.001). GCF PGE2 levels gradually increased from 38.8 ng/ml at month 1 to 79.4 ng/ml at month 6. Post-treatment: statistically and clinically significant reductions were observed in mean PI, BOP, and PD (P<0.05). A statistically significant reduction in CAL was noted (P<0.05). The trend towards progressive bone loss was halted and reversed, and a statistically significant decrease in GCF PGE2 concentrations was detected (P<0.001). Smokers, non-smokers, and ex-smokers did not differ significantly in PI, BOP, CAL, radiographic, or biochemical parameters at any time. Mean PD was significantly greater in current smokers than in non- and ex-smokers (P<0.005). PD reduced comparably in all 3 smoking subgroups following treatment (P<0.01). CONCLUSIONS: Conventional clinical measurements failed to identify disease progression over a 6-month period. Significant improvements were observed in clinical parameters after SRP, and a trend towards progressive bone loss was halted and reversed. Regular and frequent maintenance visits are important following treatment to maintain improvements in clinical parameters. Smokers had deeper probing depths than non- and ex-smokers, but pockets were reduced significantly and comparably in all 3 smoking subgroups following efficacious treatment.

Adult↗

Association of a vitamin D receptor gene polymorphism with localized early-onset periodontal diseases.

BACKGROUND: Early-onset periodontal diseases (EOP) are caused by interactions between host factors, specific microbial pathogens, and environmental factors. It is, therefore, of interest to investigate the nature of host factors as they may provide useful risk markers and reveal important information regarding the disease pathogenesis. Genetic polymorphisms in the vitamin D receptor (VDR) gene are associated with parameters of bone homeostasis and with diseases in which bone loss is a cardinal sign, in particular osteoporosis. Rapidly progressive bone loss is one feature of EOP. We, therefore, sought to determine whether EOP is associated with a polymorphism in the VDR gene. METHODS: A restriction fragment length polymorphism (RFLP) for Taq I in exon nine of the VDR gene was analyzed by PCR, followed by restriction digestion with Taq I and gel electrophoresis. We analyzed the genotypes of 69 EOP patients, including 20 patients with unequivocal evidence of localized disease (L-EOP), and 72 controls with no history of EOP. RESULTS: The genotype distribution in the L-EOP patient group was 7 (35%), 5 (25%) and 8 (40%) and in the control group 31 (43.1%), 36 (50.0%) and 5 (6.9%) for TT, Tt and tt respectively (where t and T represent the alleles with and without the Taq I RFLP respectively). Chi2 analysis indicated that the distribution of the genotypes between these two groups was highly significantly different (P = 0.001). Allele frequencies were 47.5% and 52.5% for T and t in the L-EOP group; 68.1% and 31.9% in the control group, showing a significant association between the prevalence of the less frequent allele (t) and L-EOP (P = 0.017). There was no significant difference in the genotype distribution or the allele frequencies between the control samples and the larger EOP patient group (n = 69) which included patients with generalized and localized disease. CONCLUSIONS: These data indicate that carriage of the less frequent allele of the Taq I RFLP (t) in the VDR gene significantly increases the risk of developing L-EOP. However, VDR genotype may not affect the incidence of all cases of EOP. These findings contribute to our understanding of the genetic basis for periodontal disease and may help define sub-groups of this disease which share common pathogenic factors.

Adolescent↗

Toothbrushing forces in children with fixed orthodontic appliances.

The aim of this investigation was to determine whether toothbrushing forces are influenced by wearing fixed orthodontic appliances. Thirty children, (10 males, 20 females) with planned fixed appliance therapy and aged 10-15 years, were recruited to the study. No subject had previously worn an orthodontic appliance. At baseline, each subject brushed their teeth in their usual way, unsupervised. The toothbrush used was a purpose-designed electronic instrument that measured the force applied to the brush and transmitted force data by radio to a remote PC. After toothbrushing, subjects had orthodontic brackets fitted. Toothbrushing was repeated at 2 and 14 weeks after baseline, and brushing forces recorded. There were no significant differences between the measurements made at baseline and those made at 2 and 14 weeks. There were no differences between males and females in the forces used at any time point. It was concluded that toothbrushing forces are unaffected by placing fixed orthodontic appliances in children. The brushing forces recorded were comparable with those previously found by other investigators.

Adolescent↗