Pocket Depth Measurements Research Articles

The effect of SRP on the clinical and microbiological parameters of periodontal diseases.

The purpose of the present investigation was to examine the effect of SRP on clinical and microbiological parameters in 57 subjects with adult periodontitis (mean age 47 +/- 11 years). Subjects were monitored clinically and microbiologically prior to and 3, 6 and 9 months after full-mouth SRP under local anaesthesia. Clinical assessments of plaque, redness, suppuration, BOP, pocket depth and attachment level were made at 6 sites per tooth. The means of duplicate attachment level measurements taken at each visit were used to assess change between visits. Clinical data were averaged within each subject and then averaged across subjects for each visit. Subgingival plaque samples were taken from the mesial aspect of each tooth and the presence and levels of 40 subgingival taxa were determined using whole genomic DNA probes and checkerboard DNA-DNA hybridization. The mean levels and % of sites colonized by each species (prevalence) was computed for each subject at each visit. Differences in clinical and microbiological parameters before and after SRP were sought using the Wilcoxon signed ranks test or the Quade test for more than 2 visits. Overall, there was a mean gain in attachment level of 0.11 +/- 0.23 mm (range -0.53 to 0.64 mm) 3 months post-therapy. There was a significant decrease in the % of sites exhibiting gingival redness (68 to 57%) and BOP (58 to 52%) as well as a mean (+/-SEM) pocket depth (3.3 +/- 0.06 to 3.1 +/- 0.05 mm). Sites with pre-therapy pocket depths of < 4 mm showed a non-significant increase in pocket depth and attachment level, 4.6 mm pockets showed a significant decrease in pocket depth and a non-significant gain in attachment post-therapy, while > 6 mm pockets showed a significant decrease in pocket depth and attachment level measurements post-therapy. Significant clinical improvements were seen in subjects who had never smoked or were past smokers but not in current smokers. Mean prevalences and levels of P. gingivalis, T. denticola and B. forsythus were significantly reduced after SRP, while A. viscosus showed a significant increase in mean levels. The mean decrease in prevalence of P. gingivalis was similar at all pocket depth categories, while B. forsythus decreased more at shallow and intermediate pockets and A. viscosus increased most at deep sites. P. gingivalis. B. forsythus and T. denticola were equally prevalent among current, past and never smokers pre-therapy, decreased significantly post-SRP in never and past smokers but increased in current smokers. Clinical improvement post-SRP was accompanied by a modest change in the subgingival microbiota, primarily a reduction in P. gingivalis, B. forsythus and T. denticola, suggesting potential targets for therapy and indicating that radical alterations in the subgingival microbiota may not be necessary or desirable in many patients.

Longitudinal study of prognostic factors in established periodontitis patients.

Numerous indicators for disease progression have been described in the last decade. The purpose of this study was to examine, longitudinally, a large battery of clinical, microbiological, and immunological indicators, to try to determine whether the presence of one or a combination of these parameters at baseline, would correlate positively with increased attachment and or bone loss (true prognostic factors). Following initial screening, 79 patients with established periodontitis were monitored longitudinally for one year. Whole mouth clinical measurements, plaque gingival and calculus indices, together with pocket depth and attachment level measurements, were repeated every three months. Full mouth radiographic survey, performed at baseline and 12 months, served to determine changes in crestal bone height using an image enhancement technique. Subgingival plaque samples were taken at baseline and every 3 months. Immunofluorescence assays were performed for the a battery of target microorganisms. Serum and GCF samples for IgG subclasses analysis were obtained at each visit and assayed using ELISA techniques. Likewise blood, samples were also drawn at each visit for a quantitative analysis of serum cotinine level. The overall mean attachment loss (AL) and bone loss (BL) were almost identical (0.159 mm and 0.164 mm, respectively). Individual patients variation was large (-0.733 to +1.004 mm). An overall 6.89% of sites were active; individual patients' means ranged from 0-28.9%. Mean pocket depth (PD) showed minimal change over the study period (-0.033 mm) thus suggesting that most if not all the AL was accompained by concomitant gingival recession. Smokers exhibited greater AL and radiographic BL compared to non-smokers. Likewise, patients' cotinine level showed direct correlation with outcomes of progressive periodontal breakdown. Past severity of periodontal involvement, as reflected in the patients baseline PD, AL and crestal bone height, showed good correlation with longitudinal changes in the periodontium. This correlation was higher for crestal BL as the outcome variable, while somewhat smaller for change in AL as the outcome variable. Bacteroides forsythus (Bf.), Prevotella intermedia (Pi.) and Porphyromonas gingivalis (Pg.) were frequently found in these patients. The presence of these microorganisms at baseline was associated with further disease progression. Subjects with mean baseline pocket depth equal or greater than 3.2 mm were at greater risk for future bone loss 1 year later (O.R. 2.97; C.I. 1.02-8.70). Smokers were at significantly greater risk for further attachment loss when compared to non-smokers (O.R. 5.41; C.I. 1.50-19.5). Subjects that harbored B. forsythus at baseline, were at seven times greater risk for increased pocket depth (O.R. 7.84; C.I.1.74-35.3). In conclusion, past periodontal destruction, smoking habits, Bf., Pg., & Pi. are prognostic factors for further periodontal breakdown. When designing clinical trials, or when evaluating epidemiological data, it is most important to balance for these factors. Also, treatment strategies should attempt to eliminate or modify these factors.

Sources of error for periodontal probing measurements.

This study determined the relative contribution to probing measurement reliability of several factors, compared with that of random error. Probing measurements were performed by examiners properly trained and calibrated. A total of 5771 pairs of replicate pocket depth (PD) and relative attachment level (RAL) measurements were performed with the Florida Probe. A total of 1488 replicate clinical attachment level (CAL) measurements were performed with the North Carolina 15 mm probe. In addition, longitudinal replicate measurements of RAL were performed at 0 and 12 months on 816 sites in 11 patients utilizing the Florida Probe 20 mm disk probe. Measurement reliability with the Florida Probe resulted in mean intraexaminer variances of 0.21 and 0.33, for PD and RAL, respectively (s.e.m. 0.46 mm for PD and 0.57 mm for RAL). Measurement reliability with the conventional probe resulted in mean intra-examiner variances of 0.19 for PD and 0.32 for CAL (s.e.m. 0.44 mm and 0.56 mm). Pocket depth contributed to = 5% of the variability of the intra-examiner variance with both probes with other contributing factors being the individual patient, tooth and site location. Mean intra-examiner reproducibility for duplicate RAL measurement performed at 0 and 12 months was 0.24 and 0.19, respectively (s.e.m. 0.49 mm and 0.43 mm). In conclusion, a mean intra-examiner variance of < or = 0.24 can be achieved for replicate measurements with both electronic and conventional probes for moderate and severe periodontitis patients. Individual examiner, individual patient and site location contribute up to 10% to the overall variance. Hence, the pattern of variability for intra-examiner variance of probing measurements performed with either electronic or conventional probes by trained and calibrated examiners is mostly random error.

Cell envelope and cell wall immunization of Macaca fascicularis:. effect on the progression of ligature‐induced periodontitis

The nonhuman primate, Macaca fascicularis, was used to study the role of immunization with selected members of the periodontopathic microbiota in the longitudinal progression of ligature-induced periodontitis. Animals were immunized with cell envelope antigens prepared from Porphyromonas gingivalis and Prevotella intermedia, and a mixture prepared from Fusobacterium nucleatum, Campylobacter rectus, and Actinomyces viscosus. Serum immunoglobulin G (IgG), IgM and IgA isotype antibodies increased significantly in all immunization groups and were specific for each of the immunogens. P. gingivalis and P. intermedia immunization resulted in a stabilization of the proportions of these species throughout most of the experiment. The high P. gingivalis antibody titer resulted in low P. gingivalis numbers being recovered. P. gingivalis immunization, while lowering recoverable viable P. gingivalis, resulted in significantly increased levels of Prevotella loescheii, Prevotella buccae, Bacteroides macacae and Prevotella melaninogenica compared with preligation and preimmunization levels. Actinobacillus actinomycetemcomitans, Capnocytophaga spp. and Eikenella spp. remained at preligation levels postimmunization. Campylobacter spp. increased significantly during the course of the experiment in all groups, whereas the levels of Fusobacterium spp. decreased. Plaque indices and bleeding on probing showed significant increases in all groups following ligation, with the placebo group showing the greatest increase. Pocket depth measurements revealed that , whereas the placebo animals showed an approximate 5% increase, the P. gingivalis- and P. intermedia-immunized groups showed nearly a 20% increase in pocket depth. Attachment level measurements showed significantly greater attachment loss in the P. gingivalis- and P. intermedia-immunized groups, and the F. nucleatum + C. rectus + A. viscosus immunization appeared to prevent significant changes in pocket depth/attachment level loss. Radiographic measurement of bone loss by computer-assisted densitometric image analysis revealed that the placebo group lost bone throughout the experiment. P. gingivalis- and P. intermedia-immunized groups showed an exacerbated loss of bone density and the group immunized with F. nucleatum + C. rectus + A. viscosus exhibited significantly lower amounts of bone loss when analyzed by computer-assisted densitometric image analysis, compared with the other immunized groups. Although immunization with P. gingivalis and P. intermedia cell envelope antigens had an effect on their emergence in the complex microbiota of the developing periodontal pocket, this immunization also resulted in greater bone loss than immunization with F. nucleatum + C. rectus + A. viscosus, suggesting that, whereas selective members of the putative periodontopathic microbiota may play a direct role in periodontal tissue destruction, the complexity of the subgingival microbiota dictates that considerable scrutiny is required to select useful immunogens that can elicit functional protection from periodontal tissue destruction induced by oral microorganisms that already colonize or infect the host.

Periodontal attachment loss among adults aged 60+ in South Australia.

This study aimed to provide oral epidemiological data describing periodontal destruction among older adults in South Australia. A cross-sectional survey design was employed and periodontal assessments were made among 801 persons aged 6+ drawn at random from the non-institutionalized population. Measurements of pocket depth (PD) and gingival recession (GR) were made at three sites on all teeth and used to compute loss of attachment (LOA). An average of 17 teeth per person were measured. LOA of 4+ mm at one or more sites was observed among 89.1% of persons. A mean of 78.1% of sites per person had LOA of 2+ mm (extent) and the mean LOA at sites with LOA of 2+ mm was 3.09 mm (severity). Extent and severity were greater for males and for persons aged 80+ years. Extent was virtually identical for mesio-buccal and disto-lingual sites, while severity was virtually identical for mid-buccal and disto-lingual sites. Patterns of GR and PD varied according to the jaw and type of tooth. Maxillary first and second molars had the greatest mean LOA, and the majority of LOA in the maxilla was due to PD. In the mandible there was less variation in LOA among anterior and posterior teeth, and LOA tended to be more equally divided between GR and PD. Levels of periodontal destruction of South Australia were broadly similar to results from North American studies of older adults which have used full-mouth periodontal assessments.

Prevalence of periodontitis and suspected periodontal pathogens in families of adult periodontitis patients

The aim of the present study was to investigate the prevalence of periodontopathic microorganisms and periodontal destruction in the spouses and children of adult periodontitis patients. For this study, 24 families were selected on the basis of one parent with severe periodontal breakdown and the presence of Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis and/or more than 30% Prevotella intermedia subgingivally. The clinical examination of both parents and children included pocket depth and clinical attachment loss (CAL) measurements. Samples for bacterial examination were obtained from the mucous membranes, the saliva and pockets. Pocket selection was based on the most advanced periodontitis situation found in a subject. The samples were cultured for the detection of A. actinomycetemcomitans, P. gingivalis and P. intermedia. By phase-contrast microscopy, the % of spirochetes and motile microorganisms was assessed. The number of children within each family varied between 1 and 3. In total 49 children were investigated with a range in age of 3 months to 15 years. Results showed that under the age of 5 years, none of the children had CAL, whereas in the age group of 5-15 years, 26.5% had 1-5 sites in the primary and/or permanent dentition with 1-3 mm CAL. 3 of the spouses had no interproximal CAL. 16 of the 24 spouses had a light to moderate form of periodontitis, with at least one site with 1 to 4 mm CAL and 5 spouses had severe periodontal breakdown with sites showing at least 8 mm CAL. Spirochetes, motile microorganisms and P. intermedia were frequently present in all family members. 18 out of the 24 probands were positive for P. gingivalis. This organism was found once only in a 5-year-old boy and in 11 of the spouses. A. actinomycetemcomitans was detected in 13 probands; 5 children and 5 of the spouses were also positive for this bacterium. If a child harboured one of the periodontopathogens, at least 1 of the parents was also positive for that bacterium. This phenomenon may be due to transmission of microorganisms between family members. Comparison of the clinical data reported in the present study with similar clinical parameters from epidemiological studies of the Dutch population suggest that the spouses and children of adult periodontitis patients might be at relatively high risk of developing periodontal breakdown.

The effect of partial denture connectors on gingival health.

The effect on the gingiva of a variety of relationships of a removable partial denture connector to the gingival margin was investigated in 10 subjects. Acrylic resin baseplates were designed incorporating a variety of relationships of the connector to the gingival margin. The appliances were worn for a 12 hour period daily, for 21 days. At baseline and at days 7, 21 and 49, plaque index, gingival index and probing pocket depth measurements were recorded, and subgingival plaque samples were examined using darkfield microscopy. No increase in plaque accumulation was detected in any area at any time interval. There was a significant increase in gingival index at day 21 in areas where the appliance covered the gingival margin. Small increases in probing pocket depth were recorded at day 21, there being no difference between any of the test areas. Baseline values were re-established by day 49. No significant differences were detected in the percentage of motile organisms or spirochaetes counted in the subgingival plaque samples collected from any area. It was concluded that deterioration in gingival health occurred rapidly following the insertion of a removable appliance, and that coverage of the gingival margin, irrespective of the degree of gingival relief, had a detrimental effect.

Associations between volume and flow rate of gingival crevicular fluid and clinical assessments of gingival inflammation in a population of British male adolescents.

Gingival crevicular fluid (GCF) sampling was performed on 2 occasions separated by 1 year, at 2 sites in the mouths of 102 male adolescents, mean age 17.85 years. Samples were collected onto 5 filter paper strips which were sequentially applied to the mouth of the crevice over a 9-min collection period. Volume and flow rates of GCF were determined for each site and were compared with clinical measurements of plaque, gingival colour, bleeding, gingival index (GI) and pocket depth, using a general linear models (GLM) procedure. While the initial volume of GCF showed no association with any clinical measurement, there was an association between flow rate of GCF and gingival colour. The volume of GCF collected in the final, 5th sample was associated with the GI. The sample site strongly influenced all measures of GCF volume. It is proposed that the flow rate of GCF may be a better indicator of gingival inflammation than the more imprecise clinical assessments of inflammation, since GCF flow rates more precisely reflect changes in tissue permeability. The association between the final sample, collected after 9 min, and clinical measurements, was probably a reflection of the association between clinically-detectable inflammation and the susceptibility of the site to mild irritation.

Periodontal conditions in a group of Swedish adolescents (I). A descriptive epidemiologic study

Abstract The aim of the present study was to describe, clinically and radiographically, the periodontal conditions in 16- and 18-year-old adolescents from northern Sweden. The studied samples comprised 287 16-year-olds and 283 18-year-olds. The clinical examination included recording of presence of plaque, bleeding on probing and calculus, and measurements of attachment level and pocket depth. Alveolar bone level was measured on bite-wing radiographs. A history was taken of the individual's occupation, oral hygiene habits and tobacco use, health, medication and previous orthodontic treatment. The prevalence of attachment loss (AL) was 9.4% in the 16-year-olds and 19.4% in the 18-year-olds. Proximal AL was found in 2.8% and 4.9%, respectively, and proximal bone loss in 1% in both groups. With only a few exceptions (3 individuals out of 82), the individuals with AL had their loss either at buccal/lingual surfaces or at proximal surfaces. Calculus was present in 32.7% of the 16-year-olds and in 44.9% of the 18-year-olds. Pocket >3 mm were found in 4%. No significant differences concerning the periodontal status or presence of plaque and calculus were detected between urban and rural groups or between sexes. Toothbrushing 2 or more times/day was performed by 84.3% of the 16-year-olds and by 83.7% of the 18-year-olds.

Probe tine diameter and probing depth.

The aim of this study was to assess the effect of difference in tine diameter on probing pocket depth measurement. 2 sets of tines with Williams markings at 1, 2, 3, 5, 7, 8, 9 and 10 mm, and with a "round" tip, diameter 0.5 mm, were compared. One set was described as parallel-sided, the other as tapered. The parallel-sided tine was almost parallel from the 10 mm marking to the tip (tip diameter mean = 0.46 mm, 95% C.I. 0.456-0.464), while the corresponding diameter for the tapered tine varied (tip diameter mean = 0.48 mm, 95% C.I. 0.473-0.489). Calibration markings appeared highly consistent with the expected value to within 0.01 mm. The tines were mounted in Brodontic handles at 0.25 N. Examiner probing repeatability yielded kappa 0.86 for "parallel-sided" and 0.81 for "tapered" tines in vivo. 412 approximal pockets were assessed in 53 patients with routine chronic adult periodontitis, mean age 42.1 years. Each site had a probing depth of greater than or equal to 5 mm, PlI less than or equal to 1, GI less than or equal to 1, PBI less than or equal to 1. Each site was probed 2x with a 15-min interval. At the first 251 sites, the parallel-sided tine was used initially, and the tapered at the remaining 161 sites. Results indicated a highly significant tendency for the parallel-sided tine to yield a deeper reading when a difference occurred. These findings indicate that with adequate training providing high examiner repeatability, one source of error in probing data can be minimised.

Relation of counts of microbial species to clinical status at the sampled site.

The purpose of the present investigation was to relate clinical characteristics at a site to the frequency of detection, absolute counts and proportions of 14 subgingival species. Subgingival plaque samples were removed by curette from the mesial surface of 2299 teeth in 3 healthy and 87 subjects with periodontal attachment loss. Samples were dispersed, diluted and plated on Trypticase soy agar supplemented with 5% sheep blood. After 7 days of anaerobic incubation, colonies were lifted onto nylon filters, lysed and the DNA fixed to the filters. Digoxygenin-labeled DNA probes were used to identify colonies of each test species. Measurements of pocket depth, attachment level, recession, redness, bleeding on probing and suppuration were made at each sampled site. Total viable counts at sites ranged from 10(3) to greater than 10(8) and were strongly related to pocket depth. Mean total counts at sites less than 3 mm averaged 4.6 x 10(6), while mean counts at sites greater than 7 mm averaged 2.0 x 10(7). Species enumerated and % of sites colonized were as follows; V. parvula 44; S. sanguis II 36; B. intermedius I 33; C. ochracea 31; B. intermedius II 30; S. sanguis I 29; B. gingivalis 27; S. intermedius 25; P. micros 24; W. recta 23; F. nucleatum ss vincentii 18; B. forsythus 15; A. actinomycetemcomitans serotype a 10; A. actinomycetemcomitans serotype b 8. Counts of B. intermedius II were higher at sites which exhibited gingival redness while B. intermedius I was higher at sites which bled on probing. A. actinomycetemcomitans serotype b was more frequent and at higher mean % at sites without recession. The opposite was true for S. sanguis II. B. gingivalis was somewhat more prevalent and at higher levels at suppurating sites. B. gingivalis, B. intermedius I and II and B. forsythus were found more frequently and at higher levels at sites with deeper pockets, while V. parvula was less prevalent at sites with pocket depths less than 4 mm. B. gingivalis, B. intermedius I and A. actinomycetemcomitans serotype b increased with increasing pocket depth in both localized and widespread disease subjects, but mean counts were higher in the localized disease subjects at any pocket depth. Only W. recta was found at higher levels at deep sites in widespread disease subjects when compared with similar sites in localized disease subjects. No suspected pathogens were detected in 38% of shallow sites, 31% of intermediate sites and 22% of deep sites, 2/3 of deep pockets, but less than 1/2 of shallow pockets harbored at least 2 of the suspected pathogens.

Clinical, microbiological and immunological characteristics of subjects with “refractory” periodontal disease

The aim of the present study was to analyze the relationship between attachment loss and clinical, microbiological, and immunological parameters in a group of 21 human subjects exhibiting poor response to previous periodontal therapy. All had been treated with periodontal surgery, tetracycline, and subsequent maintenance recalls to periodontists who, upon detection of disease progression, referred the subjects to our clinic. In our clinic, each subject received oral hygiene instruction and a thorough subgingival scaling and root planing utilizing as many appointments as necessary. Clinical indices, including gingival index, bleeding on probing, suppuration, plaque index, pocket depth, and duplicate measurements of attachment level from an acrylic stent, were collected at monthly intervals. Probing measurements were performed using the Florida Probe. When significant attachment loss (0.8-1.2 mm) was detected in at least 1 site, a bacterial sample was taken from that site and from a comparably deep, but non-progressing, control site. Microbial samples were enumerated by darkfield microscopy, on selective and non-selective media, and by predominant cultivable technique. Blood samples were also collected to determine antibody levels against potential pathogens. There was no difference in the amount of plaque present in sites gaining or losing attachment, but losing sites exhibited more bleeding and suppuration. 20 of the 21 subjects were tested; of these, 17 exhibited elevated serum antibody against one or more of the following microorganisms: Actinobacillus actinomycetemcomitans, Bacteroides, gingivalis, and Eikenella corrodens. However, few, if any, of the "classical" pathogens were detected in the plaque samples obtained at the time progressive disease was diagnosed. The only exception was Streptococcus intermedius, which occurred in slightly higher numbers in active sites.

A New Method to Evaluate the Capd-Catheter-Exit and other Percutaneous Devices

A method that has proved to be the most sensitive approach for the early diagnosis of infection of the oral mucosa around dental implants has been used to monitor the exit-sites of percutaneous devices. For three months the state of the skin-catheter interface of 13 CAPD-patients was examined every four weeks. This examination included the measurement of pocket depth with the aid of a periodontal probe, the measurement of SFFR (sulcus-fluid-flow-rate) using standardized filter paper strips and a bacteriological swab of the exit-site. The results obtained demonstrated that SFFR can be measured around percutaneous implants. The measurement of SFFR appeared to be more useful in the monitoring of exit-sites of percutaneous devices than the measurement of pocket depth or the use of bacteriological swabs. Further studies for prolonged periods are necessary to determine whether measurement of SFFR can reliably predict onset of exit-site infection before clinical signs become evident.

Immediate response to non‐surgical periodontal treatment in subjects with diabetes mellitus

The short-term response (3-4 months) to non-surgical periodontal treatment, i.e., oral hygiene instruction, scaling and root planing, was determined in 34 diabetic and 45 control subjects. Measurements of probing pocket depth and gingival bleeding (%) were used for evaluation. No significant difference could be observed in the response to non-surgical periodontal treatment between the diabetics and controls.

Periodontal conditions in a group of Swedish adolescents (I). A descriptive epidemiologic study

The aim of the present study was to describe, clinically and radiographically, the periodontal conditions in 16- and 18-year-old adolescents from Northern Sweden. The studied samples comprised 287 16-year-olds and 283 18-year-olds. The clinical examination included recording of presence of plaque, bleeding on probing and calculus, and measurements of attachment level and pocket depth. Alveolar bone level was measured on bite-wing radiographs. A history was taken of the individual's occupation, oral hygiene habits and tobacco use, health, medication and previous orthodontic treatment. The prevalence of attachment loss (AL) was 9.4% in the 16-year-olds and 19.4% in the 18-year-olds. Proximal AL was found in 2.8% and 4.9%, respectively, and proximal bone loss in 1% in both groups. With only a few exceptions (3 individuals out of 82), the individuals with AL had their loss either at buccal/lingual surfaces or at proximal surfaces. Calculus was present in 32.7% of the 16-year-olds and in 44.9% of the 18-year-olds. Pocket greater than 3 mm were found in 4%. No significant differences concerning the periodontal status or presence of plaque and calculus were detected between urban and rural groups or between sexes. Toothbrushing 2 or more times/day was performed by 84.3% of the 16-year-olds and by 83.7% of the 18-year-olds.

Class II Furcations Treated by Guided Tissue Regeneration in Humans: Case Reports

In the cases reported here, the response of Class II mandibular molar furcation defects to guided tissue regeneration (GTR) versus sham operation was evaluated. Base-line information, including probing pocket depth (PD) and clinical attachment level (CAL) measurements, was recorded after completion of the hygienic phase. Eleven experimental and six control furcations, randomly assigned, are included in this report. The furcations were surgically exposed, using a flap approach and the areas were debrided. On the experimental teeth, Gore-Tex periodontal material was adapted and sutured, using a suspensory suture. The flaps were then sutured tightly, assuring complete coverage to the material. For 1 month all patients were seen weekly and rinsed their mouths with an 0.12% chlorhexidine solution daily. After 4 to 6 weeks the Gore-Tex membranes were removed. Clinical measurements were repeated at 3 and 6 months following surgery. Changes from baseline in PD and CAL were calculated for each case. Results indicated that PD measurements were reduced by both procedures, but the reduction was better for GTR at 3 and 6 months. At six months the test sites showed 2.8 +/- 1.0 mm pocket reduction, while the control sites showed an average of 1.6 +/- 0.9 mm reduction in pocket depth. CAL recordings were improved by both treatments, but were better for GTR at 6 months, with an average gain in CAL of 1.8 mm for the GTR and 0.6 mm for the controls. These cases in which GTR was compared to sham-operated controls indicate that GTR can improve the response to therapy of Class II furcation defects.

Quantitative immunoassay of Treponema denticola serovar C in adult periodontitis

Murine monoclonal antibodies specific for Treponema denticola serovar C were produced and characterized in this study. An immunoassay was then developed by using these monoclonal antibodies, and the T. denticola serovar C antigen content of subgingival plaque was quantitated for samples taken from patients with periodontitis and healthy volunteers. The human subgingival plaque samples were grouped by severity of disease and pocket depth measurements at the collection site. The T. denticola serovar C content per milligram of subgingival plaque from deep pockets (greater than 6 mm) of patients with severe periodontitis was found to be twice that of samples collected from deep pockets (4 to 6 mm) of patients with moderate periodontitis or samples collected from healthy subjects (pocket depth, less than 4 mm).

Statistical Properties of Some Clinical Measures of Gingivitis and Periodontitis

Various statistical properties of the plaque index, the gingival index, and the whole-mouth averages of pocket depth and attachment level measurements were examined using data from a 4-year randomized trial of 80 patients with a history of treated periodontal disease. Departures from normality were assessed by the median of the standardized distribution, by the coefficients of skewness and kurtosis, and by the Kolmogorov goodness-of-fit test. The relative precisions of probing pocket depth and of attachment level were measured, as were correlations between repeated measurements over time for the four clinical measures. The distribution of the plaque index was far from normal, but the distribution of its logarithm was more nearly normal. The distributions of the other clinical measures were effectively normal to varying degrees of approximation. With only rare exceptions, correlations between repeated measurements on the same clinical variable remained relatively constant no matter how far apart in time the measurements were made, at least up to 4 years. The whole-mouth mean of the attachment level measurements seemed to be relatively more precise than the whole-mouth mean of the pocket depth measurements.

歯の動揺度自動診断システム

Tooth mobility is a sign of the physiological or pathological condition of the periodontium, which consists of the periodontal ligament and alveolar bone, etc. It is possible to establish tooth mobility by observing the tooth movement between pincettes or between the fingers. Further information is gained by placing the fingertips partly on the teeth and partly on the gingivae and also by asking the patient to clench his teeth and move them laterally and protrusively. A pathological mobility should always be related to the radiographic evidence of the pathogenesis and to pocket-depth measurements. Manual examination by trained observers may correspond to the degree of tooth movement, but it requires skill and experience. Measurements of tooth mobility have already been studied, and some static and sinusoidal dynamic measurements have been proposed. The authors have developed an automatic diagnosis system of tooth mobility for clinical application. This system consists of a measuring device for the biomechanical properties of the periodontium and a data analysis unit with a microcomputer. The labial crown of a tooth is randomly vibrated by a portable vibrator with a small impedance head. The mechanical mobility and parameters which give information about visco-elasticity of the periodontium are obtained. The measurement and data analysis take about 1.4s and 15s, respectively. Tooth mobility is determined objectively by discriminant analysis. The mobility triangle figure with mechanical parameters is drawn as a record for visual interpretation. The dentist can operate the diagnosis system by himself. The objective tooth mobility and viscoelastic parameters of the periodontium, which have been difficult to obtain, not only can be determined quickly but can be applied to a longterm observation of tooth mobility. This paper discusses the measuring conditions, the effects of the static preload on the tooth, the vibrating direction and the linearity to input acceleration. The preload on the tooth is 50±5gf, which does not cause pain to the subject and reflects the properties of the periodontal ligament. Vibrating deviation in the gingival-incisal direction has a more adverse effect on tooth mobility than that in the distal-mesial direction. The mechanical mobility is always measured at approximately constant acceleration 0.05G. The coefficient of variation (standard deviation/mean value) in 10 measurements is 6-9%. The physiological variations of tooth mobility over a day and a month, which are difficult to study using the usual measurements, are discussed. The validation of this system is described through clinical application to the evaluations of a healthy and a pathological tooth and some dental implantations.

5‐Year Evaluation of Durapatite Ceramic Alloplastic Implants in Periodontal Osseous Defects

Six patients who participated in a clinical study comparing the response of periodontal osseous defects to either grafting with Periograf (durapatite) hydroxylapatite (HA) ceramic or debridement alone (DEBR) were followed under an active maintenance program for 5 years. Mean values for gingival recession and attachment levels remained essentially stable following either treatment over the 5 year period. However, mean probeable pocket depths shifted from being significantly (P less than 0.05) shallower for DEBR sites at 6 months and 1 year to being significantly shallower for HA sites at 5 years. The probing pocket depth change for grafted sites was steady and the change from presurgical values was significantly greater than the change for DEBR areas, which became about 1.5 mm deeper over the 5 year postsurgical period. Intrapatient comparisons showed that recession, attachment gain, and pocket depth decrease were most frequently greater for the Periograf-treated sites. Assessment of the pattern of clinical changes during the 5 year postsurgical period demonstrated that the attachment level of grafted sites improved or stayed the same 86% of the time compared to only 62% stability or improvement in the DEBR only sites. In fact, 38% of the DEBR sites were worse at 5 years than at the time of surgery, a 3 times greater failure rate than that found in the HA-grafted sites. Pocket depth measurements showed that 98% of the Periograf-treated sites were better or the same as presurgically (2% worse), while only 80% of DEBR sites showed positive results and 20% had deeper pockets than at the time of surgery.(ABSTRACT TRUNCATED AT 250 WORDS)