A comparison of antimicrobial activity of four disclosant dyes.

Four disclosant dyes were tested for antimicrobial activity against 27 oral reference strains and five non-oral human pathogens. Erythrosine and fluorescein inhibited most gram-positive and gram-negative organisms associated with dental plaque, and were bactericidal to selected strains. Fast green and brilliant blue demonstrated little antimicrobial activity.

The effect of a new electric toothbrush on supragingival plaque and gingivitis.

This study tested the effectiveness of a rechargeable electric toothbrush, Interplak, in removing supragingival plaque and resolving gingivitis. Forty adults with gingivitis were randomly assigned to either a "manual" or "electric" group. Detailed oral hygiene instructions were given and a blind examiner assessed plaque scores before and after brushing, toothbrush abrasion, and gingival inflammation at baseline, 1, 2, and 4 weeks. Subjects using the electric brush had significantly lower (P less than 0.05) mean plaque and gingival inflammation scores. The electric group's plaque scores fell from 77% at baseline to 28% (before brushing) and 14% (after brushing) at 4 weeks; the manual group's dropped from 75% to 50% and 30% (before and after brushing, respectively). The mean G.I. for the electric group fell from 1.65 at baseline to 1.28 at 4 weeks, while the manual group's scores decreased from 1.65 to 1.43. The results suggest that the electric brush removed supragingival plaque and resolved gingivitis better than the manual brush over a 28-day period. However, a telephone survey conducted 6 months later indicated that most subjects were not using the device twice a day as they had during the study.

A new look at the etiology and pathogenesis of early-onset periodontitis. Cementopathia revisited.

For more than 20 years, investigators have unanimously agreed that human periodontitis is caused by bacterial colonization of the surfaces of the teeth and their extension apically. Recently, several investigators have demonstrated that most, if not all, individuals manifesting the early-onset, aggressive forms of periodontitis have abnormalities in their peripheral blood phagocytes which can be detected as abnormal cell motility or adherence. Because of the major role of these cells, especially the neutrophilic granulocytes, in host defense against the microbial onslaught at the gingival sulcus, these leukocyte abnormalities have been considered to be the major determinant of susceptibility to microbial infection and invasion of the periodontal tissues. In recent years the possibility that other etiologies may be involved has not been seriously considered. The purpose of the present communication is to focus attention on the idea that factors other than bacteria and host defense mechanisms may be of significance. We specifically want to call attention to a potentially important role for root cementum.

Studies of a family manifesting premature exfoliation of deciduous teeth.

We report observations made on a family in which the children manifested premature exfoliation of the deciduous incisors and canines beginning as early as 1.5 years of age. We observed gingival recession, alveolar bone resorption, tooth loosening and exfoliation without apical root resorption in the absence of clinical signs of inflammation. The children's mother, age 26, had a normal periodontium, but the father, age 30, had periodontitis of moderate severity. Exfoliated deciduous teeth from one of the children were examined histologically and features characteristic for hypophosphatasia were seen. However, localized prepubertal periodontitis could not be ruled out from these data alone. The differential diagnoses for this type of condition are discussed.

Laser Doppler measurement of gingival blood flow in dogs with increasing and decreasing inflammation.

Dramatic changes in vessel morphology and vascularization are associated with early clinical signs of gingivitis in the dog; there is conflicting evidence of both increased and decreased blood flow in the inflamed gingiva. The blood-flow rates were compared in treated and untreated gingivitis in dogs by a new, non-invasive technique, the laser Doppler flow meter (LDF). The LDF measures blood flow in 1 mm3 of the gingival margin by back-scattered light. Four adult mongrel dogs with generalized mild gingivitis were fed a dental-plaque-inducing diet. Teeth on the left were scaled and polished at zero and four weeks and brushed six times a week during the seven-week experimental period; teeth on the right were left untreated. Test teeth were the upper canines through to the fourth premolars, and lower second premolars through to the first molars. On the facial aspect of these teeth, plaque index (PlI), gingival index (GI), and gingival crevicular fluid (GCF) were assessed at weeks zero, one, four and seven. Blood flow at the gingival margin was measured with LDF at weeks one, four and seven. Acrylic appliances were used to reposition the fibre-optic probe in the same place at each follow-up examination. In a conditional binary logistic regression model, PlI, GI and GCF were significantly related to treatment (p less than 0.01), but LDF blood flow was not (p = 0.01). Blood flow increased slightly with time on the untreated side, but there was no significant decrease in blood flow with the resolution of inflammation on the treated side. Thus microvascular changes in gingival inflammation may not quickly, if ever, be reversed.

Gingival blood flow and temperature changes in young humans with a history of periodontitis.

Whether such individuals have different gingival blood flow and temperature responses to local cooling than age- and sex-matched healthy controls was tested. Ten patients with a history of localized juvenile periodontitis or rapidly progressive periodontitis were selected from a periodontal clinic and matched with healthy controls. Gingival blood flow and temperature were monitored continuously before and after cooling via a twin probe placed in the gingival sulcus on the buccal of tooth No. 26. Blood flow was assessed by laser Doppler flowmetry and temperature by a small metal thermistor. Resting values were first recorded for 5 min, followed by 3 min of cooling to 19 degrees C by a gentle stream of cool air, then 12 min of rewarming was allowed. This protocol was repeated twice. Blood flow changes were analysed as the slope of the line formed between the last 2 min of cooling and the last 2 min of rewarming; temperature curves were analysed by a least-squares curve fit of a bi-exponential function. Patients with localized juvenile periodontitis and rapidly progressive periodontitis had similar rewarming temperature curves, but significantly faster blood flow recovery curves than controls (p less than 0.03). Thus, gingival blood flow in young periodontitis patients recovered more rapidly after local cooling than in healthy controls.

Oral hygiene instruction using a self inspection plaque index.

The need for proper oral hygiene requires large amounts of time and manpower, and relapse is still common. This paper describes a self instructional manual and self inspection plaque index that was tested in a periodontal recall population. The program was tested on 18 periodontal recall patients over a period of 6 weeks. Questionnaires were completed at the start, at 2 weeks, and at the end of the experimental period to evaluate patient opinions. Presence of plaque near the gingival margin was recorded at the start, at 2 weeks, and at 6 weeks. Patients were provided with a self instructional manual which taught them to recognize plaque on six teeth. Also, they were given a lighted mouth mirror, a toothbrush, and disclosing wafers. Initial, before-brushing plaque scores of 47% decreased to 18% during the 6 weeks of the study. After-brushing plaque scores also were significantly improved during the study. Patients were able to perform the plaque index without guidance to a high level of agreement with a dental hygienist (r = 0.72). Furthermore, the program was well accepted by the patients according to their answers on the questionnaire.

Whistleblowing in dentistry: what are the ethical issues?

What should you do when you see another dental professional's substandard work? What dental professionals are most likely to encounter whistleblowing dilemmas? Generic components of whistleblowing that apply to dentistry and factors to consider when choosing to report are discussed.

Subgingival microflora in bleeding and nonbleeding pockets.

The subgingival flora of bleeding and nonbleeding 4-6 mm pockets was investigated using phase-contrast microscopy. Subgingival plaque was sampled from 11 patients with generalized moderate periodontitis. 4 subgingival samples were obtained from each patient, 2 from sites that bled upon standardized probing force and 2 from sites that did not. The amounts of gingival inflammation, supragingival plaque, attachment level and pocket depth were also assessed at each site. The %s of 4 bacterial morphotypes were assessed using phase-contrast microscopy. No significant differences were found in the %s of cocci, motile rods, or spirochetes between bleeding and nonbleeding sites. Significant correlations were found, however, between the % of spirochetes and probing depth, attachment level, and gingival inflammation. The observations indicate that the use of bleeding on probing may not be justified as an indicator of infection by those "periodontopathic" bacteria identifiable by phase-contrast microscopy. However, limitations in the microscopic method may have prevented us from observing differences between the 2 types of sites on a species level.

The effect of cigarette smoking on gingival blood flow in humans.

This paper presents the acute effects of cigarette smoking on blood flow to the gingiva in 12 young smokers. Relative gingival blood flow (GBF) was measured by a laser Doppler fiberoptic probe placed 1 mm into the buccal sulcus of tooth no. 26. The probe continuously measured the flux of blood cells (velocity X number of cells) in the gingival crest. Relative skin blood flow (SBF) to the forearm and heart rate were also monitored continously; blood pressure (BP) was assessed at 5-min intervals. After resting for 5 min, subjects sham smoked an unlighted cigarette for 5 min, then smoked the cigarette, and finally rested for 25 min afterwards. Mean changes from resting for all variables were compared to sham smoking for each 5 min block. Mean GBF rose significantly above sham smoking values during smoking, and remained elevated during the first 5 min after smoking (p less than 0.05). Mean SBF decreased slightly during and after smoking, but the changes were not significantly depressed compared to sham smoking (p greater than 0.05). During smoking, BP and heart rate increased significantly over sham smoking (p less than 0.05). GBF increased almost linearily when the probe was placed into the gingival sulcus; this phenomenon did not occur when the probe was placed externally to the gingival crest. The theory that smoking impairs gingival blood flow may not be true in humans.

Measures of treatment efficacy.

Measures of treatment efficacy are those numbers we think about when we decide whether one treatment is "better" than another. Such measures quantify the differences between treatments and help patients and clinicians make informed choices. The usual measure of treatment efficacy in periodontal research has been the mean difference between treatments in probing level measures. This measure has frustrated clinicians and researchers alike for its failure to communicate the size of the association between treatment and clinical outcome. How does one interpret the clinical relevance of a small mean difference between treatments, such as 0.4 mm? This report compares the advantages and disadvantages of the different measures of treatment efficacy: the mean difference, the relative risk, significance levels (P-values), the risk difference, and, the preventable fraction.

The power of tests to detect differences between periodontal treatments in published studies.

10 studies comparing periodontal treatment modalities were re-examined to see if they had adequate power to detect true differences. Attachment level (AL) and pocket depth (PD) were the 2 variables assessed. A statistical test's power refers to its probability of detecting a significant sample difference in treatment means, given a predetermined value for alpha (level of significance), delta (a clinically meaningful underlying difference), and the sample size. Studies were included that stratified their data by initial pocket depths, reported sample size, and lasted at least 6 months. Power calculations were done for 173 treatment comparisons, using delta = 0.5 mm and alpha = 0.05. For shallow pockets (1-3 mm), most studies had a strong chance of detecting true differences (median power = 83%). For moderate pockets (4-6 mm), median power dropped to 38%. However, median power dropped to 14% for deep pockets (> 6 mm), with 75% of the tests having less than a 20% chance of detecting a 0.5 mm difference. Many of the modalities reported as "not significantly different" from each other have not had a fair trial, especially for deep pockets. In order to improve a study's power, 4 factors are discussed: the number of compared treatments, the expected noise or random error, the patient sample size, and the average number of sites per patient for each pocket depth category.

Caries and periodontitis associated with an unerupted third molar.

Radiographic, gross, and histologic evidence is provided to demonstrate the development of caries and periodontal disease over a 5-year period in an unerupted tooth. The authors speculate on the pathogenesis of these disease processes.

Defective neutrophil and monocyte motility in patients with early onset periodontitis.

Several studies have documented suppressed polymorphonuclear neutrophil (PMN) chemotaxis in most patients with juvenile periodontitis. In contrast, data regarding PMN chemotaxis in patients with rapidly progressive periodontitis are very limited, and monocyte (MN) chemotaxis and random migration of PMNs or MNs from these patients have not been studied previously. Accordingly, we examined cell motility of PMNs and MNs from 27 patients with rapidly progressive periodontitis, 5 patients with juvenile periodontitis, and 37 normal control subjects by using a microchamber technique and the synthetic peptide N-formylmethionyl-leucyl-phenylalanine (FMLP) as the chemoattractant. As a group, PMNs and MNs from patients with rapidly progressive periodontitis manifested significantly enhanced random migration relative to control cells (P less than 0.001), suppressed directed migration (chemotaxis) at FMLP doses of 10(-9) and 10(-8) M (P less than 0.05), and enhanced directed migration at a dose of 10(-6) M FMLP (P less than 0.01). In contrast, PMNs from patients with juvenile periodontitis exhibited normal random migration, and directed migration was significantly suppressed at all doses of FMLP tested (P less than 0.05). An abnormality of either PMN or MN motility was observed in 26 of 27 patients with rapidly progressive periodontitis. Enhanced random migration was seen in PMNs in 63%, MNs in 39%, and both cell types in 26% of the patients. Suppressed chemotaxis was seen in PMNs in 85%, in MNs in 74%, and in both cell types in 69% of the patients. The prevalence and magnitude of abnormalities in motility were somewhat lower in treated than in untreated patients. Thus, most, if not all, of this subgroup of patients with early onset, highly destructive periodontitis have abnormalities in PMN or MN motility, and these defects may differ from those seen in cells from patients with the juvenile form of the disease.

Laboratory studies of a family manifesting premature exfoliation of deciduous teeth.

In a previous publication, we described the clinical and radiographic findings of a family in which the children manifested premature exfoliation of the deciduous teeth. We now report for the same family the results of extensive laboratory studies performed on blood and urine, analysis of periodontal microflora, and a family pedigree. We demonstrated the presence of putative periodontal pathogens in the subgingival microflora, elevated levels of serum antibodies reacting to Bacteroides gingivalis, Capnocytophaga gingivalis, and C. sputigena in 2 of the children, and significantly suppressed monocyte chemotaxis in all 3 children. Phosphoethanolamine was found in the urine of the father and all 3 children, but not in the mother. Likewise, serum alkaline phosphatase was abnormally low for all 3 children, and was at the extreme low end of normal range for the father, but was normal for the mother. On the basis of the alkaline phosphatase and phosphoethanolamine measurements, we assigned a diagnosis of hypophosphatasia to the 3 children. Phosphoethanolamine and alkaline phosphatase were also abnormal in the paternal grandmother and her brother. The son of this brother who was deceased had a daughter manifesting premature loss of the primary teeth. The data are consistent with an autosomal dominant mode of transmission. In the light of our findings, hypoplastic cementum must be considered in the etiology of some forms of early-onset periodontitis.