Attachment loss after scaling and root planing with different instruments. A clinical study

OBJECTIVES

The aim of this study was to evaluate clinically the immediate effect of trauma from instrumentation after scaling and root planing with different instruments.

MATERIAL AND METHODS

Ten subjects with moderate chronic periodontitis, presenting probing depths ranging from 3.5 to 6.5 mm on anterior teeth, upper and/or lower, were selected. Teeth were randomly assigned to one of the following groups: MC group--scaled and planed with Gracey mini-curettes (MiniFive); CC group--scaled and planed with Gracey conventional curettes. The selected teeth were probed with a computerized electronic probe, guided by an occlusal stent, and then subjected to scaling and root planing. Immediately following instrumentation, teeth were probed again. The difference between relative attachment level (RAL) immediately before and after instrumentation was considered as trauma from instrumentation.

RESULTS

Intra-group analysis revealed statistically significant differences between RAL immediately before and after instrumentation in both groups (0.68 +/- 0.32 for MC group; and 0.83 +/- 0.41 for CC group--p < 0.05). However, inter-group analysis did not show a statistically significant difference in trauma from instrumentation caused by the different instruments.

CONCLUSIONS

Within the limits of this study, it was concluded that root instrumentation causes an average trauma from instrumentation of 0.76 mm with no differences between the tested instruments.

Clinical and microbiological associations in chronic periodontitis

Chronic Periodontitis is the most prevalent form of periodontal disease. The subgingival microflora has been associated with the onset and progression of the disease. The aim of this work was to establish associations and correlations between clinical indicators and subgingival plaque microbiological data in patients diagnosed with moderate or severe Periodontitis. One hundred sites with a probing depth of > or = 5 mm were selected. Plaque Index (PI), Gingival Index (GI), Bleeding on Probing (BP), Probing Depth (PD) and Clinical Attachment Level (CAL) were measured. The subgingival plaque microbiological assay comprised cultures in selective and non-selective media and identification tests for Porphyromonas gingivalis (Pg), Prevotella intermedia/nigrescens (Pi/n), Actinobacillus actinomycetemcomitans (Aa), Fusobacterium (F) and Peptostreptococcus micros (Pm). Dark field microscopy was used to analyze the relative proportions of Treponema to the total microbial morphotypes. Small Treponeina (ST), Medium Treponema (MT), Large Treponema (LT) and Total Treponema (TT) were determined. Our results showed associations and a correlation between PD and AL, r = 0.62 (p<.0001); PD and Pg X2 = 15.22, r = 0.39 (p<.001); AL and Pg X2 = 10.72, r = 0.32 (p<.001). A negative correlation was observed between Pg and Pi/n X2 = 12.65, r = -0.35 (p<.001); BP and F X2 = 8.93; GI and F X2 = 8.92. The present results reveal associations and correlations between some clinical indicators and subgingival plaque microorganisms in patients diagnosed with Chronic Periodontitis.

Clinical course of chronic periodontitis

AIM

The purpose of this study was to assess the rate of attachment loss during various stages of adult life in a well-maintained middle-class population.

MATERIAL AND METHODS

The data originated from a 26-year longitudinal study of Norwegian males who had received regular and adequate dental care and practised daily oral home care. The initial examination in 1969 included 565 individuals aged between 16 and 34 years. Subsequent examinations took place in 1971, 1973, 1975, 1981, 1988 and 1995. Thus, the study covers the age range of 16-59 years. The rate of the annual attachment loss was calculated as the difference between the individual mean attachment loss between two examinations divided by the years between examinations. The mean annualized relative risk of attachment loss was calculated as the frequency distribution of sites with initial periodontal attachment loss (loss of attachment at the first time of occurrence > or = 2 mm) and healthy sites (loss of attachment always < 2 mm). For comparison of significant changes in annual attachment loss rates between the age groups and mean annualized relative risks of attachment loss as they proceeded through adult life, the Wilcoxon Mann-Whitney U-test was used.

RESULTS

The mean overall individual attachment loss during 44 years (between 16 and 59 years) totaled 2.44 mm (range 0.14-2.44 mm), averaging an annual mean rate of 0.05 mm/year. The highest annual rate of attachment loss occurred before 35 years of age (0.08-0.1 mm/year), after which the mean annual rate decreased to about 0.04-0.06 mm/year for the next three decades of life leading to 60 years. The mean annualized relative risk of initial attachment loss increased significantly from adolescence (1.2%) to the maximum at 30-34 years of age (6.9%). After the age of 34 years, the risk of initial attachment loss decreased again, but after the age of 40 years, another continuous increase was observed.

CONCLUSIONS

Over a 26-year period, 25% of the subjects went through adult life with healthy and stable periodontal conditions. The remaining 75% developed slight to moderately progressing periodontal disease with progression rates varying between 0.02 and 0.1 mm/year with a cumulative mean of loss of attachment of 2.44 mm as they approached 60 years of age. The annual mean rate and the mean annualized risk of initial attachment loss were highest between 16 and 34 years of age. Only 20% of the sites continued to lose further attachment during the remainder of the observation period, and less than 1% of the sites showed substantial loss of attachment (> 4 mm).

The distribution of periodontal disease and loss of attachment in jaw sextants in different age groups--cross-sectional study

The distribution of periodontal disease stages is not the same in both human jaws, parts of the same jaw or in different ages of life. In the sample of 2,730 sextants, 455 persons 15+ years of age, analysis of distribution of both periodontal disease and loss of attachment in jaw sextants in different age groups was made, using the Community Periodontal Index (CPI) and Loss of Attachment (LA). Statistical significance testing was checked using the Pearson Chi-Square-test with probability of 95%. Healthy periodontium is mostly found in upper anterior sextant (36%, p < 0.001), and bleeding on probing in lower right sextant (25.45%, p < 0.001). There is most calculus in lower anterior sextant (48.19%, p < 0.001), followed by upper posterior (15-17%). Deep pockets are more often in lower anterior sextant (31.87%, p < 0.001), and upper and lower posterior sextants are without teeth in 18-20.5% of cases, but lower anterior sextant in only 7.73% (p < 0.001). Cumulative minimal loss of attachment (0-3 mm) significantly is more often present in upper anterior sextant (21.2%, p < 0.001), while values 5-11 mm are more often in lower anterior sextant (25-43%, p < 0.001). Loss of attachment > or = 12 mm appears in only 1.4% present sextants and it is rear on left jaw side. Significant differences in distribution of both periodontal disease and loss of attachment appear in age 30+.

Root surface debridement and endotoxin removal

OBJECTIVE

This study assessed associations between the number of standardized scaling strokes and the reduction of endotoxin on the root surface.

BACKGROUND

Therapy of periodontally involved teeth attempts removal of accretions by scaling and root planing. The amount of mechanical therapy required to free the root surface from etiologic factors remains unknown.

METHODS

Twenty-four extracted human caries-free single rooted teeth with at least 5 mm attachment loss were used. A region of interest (ROI) which contained subgingival calculus was defined on the root surface of each tooth. Standardized force instrumentation was applied using a force-measuring curet. Fifty working strokes were applied to every ROI. Forces applied were recorded. The force recordings were converted from Millivolts into Newtons (N). After every unit of 5 strokes, presence of calculus was evaluated and scaling debris was collected. Endotoxin concentration was determined in the debris samples.

RESULTS

The endotoxin values for strokes 1-5 were statistically significantly greater than the values from all other stroke intervals. Complete calculus removal occurred after a mean of 9.3 strokes. The endotoxin concentration reached a minimal level with concentrations of 0.03-0.306 EU/ml after calculus removal was complete.

CONCLUSION

These findings suggest that completion of calculus removal coincides with endotoxin levels associated with clinically healthy teeth.

On the precision of the conditionally autoregressive prior in spatial models

Bayesian analyses of spatial data often use a conditionally autoregressive (CAR) prior, which can be written as the kernel of an improper density that depends on a precision parameter tau that is typically unknown. To include tau in the Bayesian analysis, the kernel must be multiplied by tau(k) for some k. This article rigorously derives k = (n - I)/2 for the L2 norm CAR prior (also called a Gaussian Markov random field model) and k = n - I for the L1 norm CAR prior, where n is the number of regions and I the number of "islands" (disconnected groups of regions) in the spatial map. Since I = 1 for a spatial structure defining a connected graph, this supports Knorr-Held's (2002, in Highly Structured Stochastic Systems, 260-264) suggestion that k = (n - 1)/2 in the L2 norm case, instead of the more common k = n/2. We illustrate the practical significance of our results using a periodontal example.

Interleukin-1beta, clinical parameters and matched cellular-histopathologic changes of biopsied gingival tissue from periodontitis patients

OBJECTIVE

The aim of the present study was to investigate whether interleukin (IL)-1beta in diseased tissues adjacent to periodontal pockets can reflect the degree of inflammation and destruction of these tissues pathologically.

BACKGROUND

IL-1beta-dependent mechanisms have been strongly implicated in contributing to inflammation and destruction of bone and attachment loss, which are characteristic features of periodontal disease. This biochemical mediator released during pro-inflammatory processes has not been objectively integrated with clinical and histopathologic features of periodontal disease.

METHODS

Periodontitis-affected inflamed tissue and clinically nonaffected healthy gingivae were harvested from 14 periodontal patients, respectively. The severity of tissue inflammation was illustrated by clinical parameters and cellular histologic changes and quantified by histometric assessments. IL-1beta in these extracted specimens was measured with an enzyme-linked immunosorbent assay (ELISA) technique. Pathogenic roles that IL-1beta plays in gingival inflammation and pathologic tissue changes in tissue sections were analyzed statistically.

RESULTS

The overall total tissue IL-1beta, tissue concentration of IL-1beta, and percentage of inflammatory cell infiltration (PICI) determined from diseased gingivae were obviously higher than those of controls from both healthy sites of periodontitis and non-periodontitis subjects. With increasing gingival index (GI), plaque index (PlI), and probing depth (PD), there was a marked elevation in total tissue IL-1beta. Total tissue IL-1beta was significantly correlated with GI, PlI, the PICI, and tissue alterations. Polymorphonuclear leukocytes (PMNs) and monocyte-macrophage cells seemed to predominate in heavily infiltrated areas of diseased gingiva. These cell types were confirmed by immunocytochemical localization with either monoclonal mouse antihuman neutrophil elastase antibody or monoclonal mouse antihuman macrophage (CD68) antibody, respectively. Total tissue IL-1beta and the PICI were also elevated in diseased gingivae near deeper PD, while neither total IL-1beta nor tissue concentration was statistically correlated with PD. Thus, correlation analysis indicates that IL-1beta level in inflamed periodontal tissues correlates highly with clinical parameters (GI and PlI) and PICI (the degree of inflammation).

CONCLUSIONS

These observations suggest that IL-1beta plays a significant role in the pathogenic mechanisms of periodontal tissue destruction, and that measurement of tissue IL-1beta would be a valuable aid and useful for diagnostic markers of periodontal diseases.

Influence of subcutaneous administration of recombinant TNF-alpha on ligature-induced periodontitis in rats

Proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) was found in inflamed periodontal tissues and many studies pointed to its significant role in development of periodontal disease. In this study, the influence of subcutaneously administered recombinant human TNF-alpha (rhTNF-alpha) on inflammatory reaction and periodontal breakdown in rats was analyzed during experimental periodontitis, induced by placing silk ligatures around the maxillary right second molar tooth. The rats were divided into two groups with five animals in each; the first group was infused subcutaneously with rhTNF-alpha via osmotic pumps for 2 weeks and the second group was infused with phosphate-buffered saline (PBS) in the same manner. Inflammatory reaction and periodontal breakdown was evaluated morphometrically on hematoxylin and eosin stained sections. Serum ionized calcium and inorganic phosphates were monitored colorimetrically. Serum calcium and phosphate levels were similar in rats receiving rhTNF-alpha and PBS. Ligation resulted in accelerated periodontal breakdown, while subcutaneous rhTNF-alpha administration by itself had no significant effect. Combined effect of subcutaneous rhTNF-alpha administration and ligation resulted in a significantly greater inflammatory reaction and periodontal breakdown then either treatment alone. We concluded that the subcutaneous administration of rhTNF-alpha accelerates the progression of experimental periodontitis in rats.

Enamel matrix proteins in the treatment of periodontal sites with horizontal type of bone loss

OBJECTIVES

The present study aims to assess the clinical and radiographic outcome of horizontal type of bone loss over a period of 8 months following periodontal surgery with adjunctive use of enamel matrix proteins (EMP).

MATERIALS AND METHODS

Twenty patients, who received nonsurgical periodontal therapy and had radiographic horizontal bone loss with an associated probing depth (PD) of > or =4 mm at the maxillary incisor/canine segment, were included. One side of the selected segment divided by the mid-sagittal plane was treated with EMP as part of a crevicular flap. The other side was treated either with a similar intracrevicular (ICI) or a reverse bevel incision (RBI) as part of a conventional flap debridement. Therefore, patients were divided into two groups of 10 patients according to the type of incision performed on the control side. The analysis was based on a classification of two severity groups according to preoperative PD, with the patient's means of measurements for each treatment being the experimental units for the statistical analysis.

RESULTS

For pockets of 4-6 mm, EMP treatment was significantly better than the ICI/flap debridement in terms of PD reduction (p<0.001), relative attachment level (RAL) gain (p<0.001) and recession (REC) (p<0.05). Although sites exposed to EMP treatment exhibited significantly greater RAL gain than RBI/flap debridement sites (p<0.01), both treatments resulted in equally effective PD reduction. Less REC occurred with EMP application than with ICI-RBI/flap debridement (p<0.05). Treatment of shallow sites by the conventional flap with both incisions resulted in a tendency for loss of attachment whereas EMP treatment maintained the attachment levels. No significant difference in the degree of probing and radiographic bone levels was found between the treatments.

CONCLUSION

EMP treatment showed better clinical improvements as compared to the conventional flap debridement performed with two different incisions. Clinical improvements were more pronounced at periodontal sites with deep, rather than shallow, periodontal pockets. The results of this study provided an important preliminary base for further clinical and histologic studies.

Unification of the "burst" and "linear" theories of periodontal disease progression: a multilevel manifestation of the same phenomenon

Previously, burst and linear theories for periodontal disease progression were proposed based on different but limited statistical methods of analysis. Multilevel modeling provides a new approach, yielding a more comprehensive model. Random coefficient models were used to analyze longitudinal periodontal data consisting of repeated measures (level 1), sites (level 2), teeth (level 3), and subjects (level 4). Large negative and highly significant correlations between random linear and quadratic time coefficients indicated that subjects and teeth with greater-than-average linear change experienced decelerated variation. Conversely, subjects and teeth with less-than-average linear change experienced accelerated variation. Change therefore exhibited a dynamic regression to the mean at the tooth and subject levels. Since no equilibrium was attained throughout the study, changes were cyclical. When considered as a multilevel system, the "linear" and "burst" theories of periodontal disease progression are a manifestation of the same phenomenon: Some sites improve while others progress, in a cyclical manner.

Clinical and histologic evaluation of human intrabony defects treated with an enamel matrix protein derivative combined with a bovine-derived xenograft

The purpose of the present case report study was to clinically and histologically evaluate the healing of deep intrabony defects following treatment with either a combination of an enamel matrix protein derivative (EMD) and a bovine-derived xenograft (BDX) or with BDX alone. Three female patients with generalized marginal periodontitis and presenting one advanced intrabony defect each were treated with either a combination of EMD + BDX (two defects) or with BDX alone (one defect). The postoperative healing was uneventful in all three cases. Six months after surgery, a gain of clinical attachment was measured at all treated sites. The histologic examination revealed that all three defects healed with a new connective tissue attachment (ie, new cellular cementum with inserting collagen fibers) and new bone. Most of the BDX particles were surrounded by a bone-like tissue. No direct contact between BDX particles and the root surface (cementum or dentin) was observed. Within their limits, the present data indicate that treatment with either EMD + BDX or with BDX alone may enhance the formation of new connective tissue attachment and new bone in human intrabony defects.

Evaluation of periodontal regeneration following grafting intrabony defects with bio-oss collagen: a human histologic report

This study evaluated the clinical, radiographic, and histologic response to Bio-Oss Collagen when used alone or in combination with Bio-Gide bilayer collagen membrane for the treatment of four intrabony defects (5 to 7 mm) around single-rooted teeth. After reflecting a full-thickness flap, thorough degranulation and root planing were accomplished. In all cases, Bio-Oss Collagen was then used to fill the defects, and in two cases, a Bio-Gide membrane was placed over the filled defect. Radiographs, clinical probing depths, and attachment levels were obtained before treatment and immediately preceding en bloc resection of teeth and surrounding tissues 9 months later. Reduction in pocket depth and gain in clinical attachment level were observed for both treatment protocols. The histologic evaluation demonstrated the formation of a complete new attachment apparatus, evidencing periodontal regeneration that varied with defect morphology. This human histologic study demonstrated that Bio-Oss Collagen has the capacity to induce regeneration of the periodontal attachment apparatus when placed in intrabony defects.

Effect of a collagen membrane enriched with fibronectin on guided tissue regeneration in dogs

The present study was planned to assess the capacity of a resorbable collagen membrane enriched with fibronectin to prevent the apical migration of epithelium and to facilitate new attachment and new bone. Experimental osseous dehiscence defects were produced on the bilateral labial aspect of mandibular 2nd, 3rd and 4th premolar teeth in six mongrel dogs. Guided tissue regeneration therapy using collagen membranes, which were rehydrated with fibronectin solution, was performed on one quadrant (group A). In the contralateral quadrant, the same collagen membranes, but rehydrated only with saline (group B), were placed over the bony defects. The third premolar teeth, which were treated by open-flap debridement, served as control (group C). Flaps were positioned slightly coronally and sutured; sutures were removed 10 days later. The dogs were killed 30 days after reconstructive therapy. Tissue blocks containing the experimental and control teeth were excised, demineralized in EDTA, and embedded in paraffin. Histological and histometric evaluation revealed that all groups demonstrated similar effects on preventing the down-growth of epithelium and formation of new cementum and new bone. Collagen membranes were tolerated well within the tissues, and membrane remnants were identified at 30 days. In summary, this study indicated that in this dog model similar healing results could be achieved with a bovine type I collagen membrane with or without fibronectin solution and open-flap debridement.

The effects of EDTA gel conditioning exposure time on periodontitis-affected human root surfaces: surface topography and PDL cell adhesion

OBJECTIVE

The purpose of this investigation was to study the surface topography of periodontally-affected human roots following EDTA gel application at different time periods with and without scaling and root planing. In addition, to assess any correlations between root surface changes following EDTA gel conditioning and periodontal ligament fibroblast adhesion.

METHODS

Forty-eight teeth that had a labial probing depth and clinical attachment loss of more than 7mm were used in this study. Periodontally-affected teeth were randomly divided into 4 groups of 12 teeth in each. Furthermore, a sample group of 6 teeth, which had a healthy periodontium, were used to serve as the healthy control (G1). The second group (G2) served as a diseased treated control in which sample teeth were only scaled and root planed prior to immediate extraction. Teeth in the third group (G3) were conditioned with a pH neutral, 24% Ethylenediaminetetraacetic acid (EDTA gel), for 2 minutes without any scaling or root planing and immediately extracted. The teeth in the fourth group (G4) were scaled, root planed, and then conditioned with the EDTA gel preparation for 2 minutes before immediate extraction. Finally the teeth in the fifth group (G5) were conditioned with EDTA gel for 4 minutes following scaling and root planing and immediately extracted. Half the samples in each group were randomly selected and processed for SEM evaluation of the surface topography. The other half were prepared to assess PDL cell adhesion with PDL fibroblasts being cultured and seeded on the root surface for 24 hours then processed for SEM evaluation of the adherent cells.

RESULTS

SEM evaluation of the root planed surfaces in G2 revealed the typical appearance of a smear layer. The root surfaces of all samples in G3 exhibited a uniform coating of calculus that was covered by a considerable amount of loosely attached material including residual plaque and debris. In G4 EDTA gel exposure for 2-minutes following scaling and root planing resulted in removal of the smear layer and a marked exposure of round to oval dentinal tubule orifices. Areas of bacterial accumulation were observed in 4 out of the 6 samples examined in this group. The root surfaces after the 4-minute EDTA gel application (G5) had a fibrillar texture associated with a marked decrease in the number and an increased diameter of the exposed dentinal tubule openings. With regard to PDL cell adhesion, the majority of the 2-minute EDTA gel conditioning on the non-instrumented samples in G3, showed a failure of cells to adhere to the diseased root surface. The examined samples in G4 showed a significant increase in the number of flat and round adherent cells when compared to the diseased control samples (G2) (P > or = 0.01). The G5 samples showed a significant increase in the number of flat cells when compared to G4 (P > or = 0.01).

CONCLUSION

The present study confirms the capability of EDTA gel to remove a root surface associated smear layer and to expose a collagen matrix when it was applied after scaling and root planing. In addition, a positive correlation was found between time of EDTA gel conditioning and the degree of PDL cell adhesion. It appears from the present investigation that EDTA gel conditioning for 4 minutes provides the most desirable root surface to which maximum PDL cells can adhere and on which they can grow.

Healing of intrabony defects following treatment with a bovine-derived xenograft and collagen membrane. A controlled clinical study

AIM

: The purpose of the present study was to compare clinically the treatment of deep intrabony defects with a combination of a bovine-derived xenograft (BDX) and a bioresorbable collagen membrane to access flap surgery.

METHODS

: Twenty-eight patients suffering from chronic periodontitis, and each of whom displayed one intrabony defect, were randomly treated with BDX + collagen membrane (test) or with access flap surgery (control). Soft tissue measurements were made at baseline and at 1 year following therapy.

RESULTS

: No differences in any of the investigated parameters were observed at baseline between the two groups. Healing was uneventful in all patients. At 1 year after therapy, the test group showed a reduction in mean probing depth (PD) from 9.2+/-1.3 to 3.9+/-0.7 mm (p<0.001) and a change in mean clinical attachment level (CAL) from 10.2+/-1.5 to 6.2+/-0.5 mm (p<0.0001). In the control group, the mean PD was reduced from 9.0+/-1.2 to 5.2+/-1.8 mm (p<0.001) and the mean CAL changed from 10.5+/-1.5 to 8.4+/-2.1 mm (p<0.01). The test treatment resulted in statistically higher PD reductions (p<or=0.05) and CAL gains (p<0.001) than the control one. In the test group all sites (100%) gained at least 3 mm of CAL. In the control group no CAL gain occurred in four sites (29%), whereas at six sites (43%) the CAL gain was 2 mm. A CAL gain of 3 mm or more was measured in four defects (29%).

CONCLUSIONS

: Within the limits of the present study, it can be concluded that: (i) at 1 year after surgery both therapies resulted in significant PD reductions and CAL gains, and (ii) treatment with BDX+collagen membrane resulted in significantly higher CAL gains than treatment with access flap surgery.

Treatment of adjacent gingival recessions with subepithelial connective tissue grafts and the modified tunnel technique

OBJECTIVE

There has been great interest in the treatment of gingival recession defects, especially with subepithelial connective tissue grafting. Recent advances have focused on subepithelial connective tissue grafting by the tunnel technique. In this clinical study, a modified periodontal plastic surgery technique for coverage of adjacent gingival recessions was performed. This surgical modification was based on the tunnel technique without vertical incisions, where the partial dissection was converted to a full-thickness dissection at the mucogingival area to supply more blood vessels.

METHOD AND MATERIALS

Patients, each contributing at least two adjacent buccal gingival recessions, were treated. Subepithelial connective tissue grafting was used to cover the defects. Gingival recession, probing depth, and attachment level were measured at baseline and 8 months posttreatment.

RESULTS

There were statistically significant improvements in attachment level and gingival recession after 8 months; the mean gain in attachment was 3.67 mm and the mean root coverage was 3.28 mm, which translated to mean root coverage of 95%.

CONCLUSION

These findings suggest that subepithelial connective tissue grafting with a modified tunnel approach, in which the partial-thickness flap is converted to a full-thickness flap in a coronoapical direction, results in adequate early healing and highly predictable root coverage in adjacent gingival recessions.

Longitudinal study on periodontal conditions in healthy elderly people in Japan

OBJECTIVES

A strategy for the control of periodontal disease progression is required to prevent tooth loss in older people. However, detailed epidemiological data on periodontal conditions in elderly people is limited. The purpose of the present study is to describe the natural history of periodontal disease and to evaluate the intraoral factors relating to the disease progression in systemically healthy elderly people.

METHODS

In the cross-sectional study, 599 and 162 subjects aged 70 and 80 years, respectively, were examined. Of those subjects aged 70 years, 436 (73%) participated in the 2-year longitudinal study. Pocket depth (PD) and attachment level (AL) were measured for all functioning teeth at six sites per tooth. In the cross-sectional study, AL of 4 mm or greater and 7 mm or greater were defined as moderate and severe disease, respectively. In the longitudinal study, a change in AL of 3 mm or greater at each site was defined as periodontal disease progression.

RESULTS

In the cross-sectional study, 97.1% of the subjects had at least one site of AL of 4 mm or greater (4+ mm). The prevalence of AL of 7 mm or greater (7+ mm) was 47.9%, with 2.8 affected teeth per person in those with AL 7+ mm. These findings reveal that periodontal disease is extremely widespread in the elderly population. However, very few had many teeth with severe periodontal conditions. In the longitudinal study, 75.1% experienced attachment loss of 3 mm or greater (3+ mm) during the 2-year study period. Of those subjects who experienced attachment loss, a mean of 4.7 teeth exhibited attachment loss. Multivariate logistic regression showed that both the highest AL in each tooth at baseline and abutment teeth for removable partial dentures were significantly related to periodontal disease progression as well as tooth loss incidence.

CONCLUSIONS

These results suggest that teeth with poor periodontal conditions as well as abutment teeth for removable partial dentures were significant intraoral factors relating to periodontal disease progression as well as tooth loss.

Relationships Among Clinical Measures of Periodontal Disease and Their Associations With Systemic Markers

BACKGROUND

Recent investigations of the relationship between periodontitis and systemic disease require that periodontal disease also must be thought of as a disease process that is an exposure for a systemic disease or condition (outcome), rather than as the outcome itself. When viewing periodontal disease as an exposure, investigators must consider the clinical, microbiological, and inflammatory components of periodontitis that potentially convey risk for the systemic outcome of interest, which may or may not be the same as those associated with the assessments used to define tooth-based disease. Another important consideration is the temporal relationship between the exposure and the outcome of interest.

METHODS

To explore which definitions of periodontal disease or clustering of clinical signs are important with regards to systemic exposure to inflammatory stress, we examined the relationship between clinical periodontal disease measures and 2 systemic inflammatory markers of increased risk for cardiovascular disease: serum soluble intercellular adhesion molecule (sICAM), which is a measure of vascular stress and serum C-reactive protein (CRP), which is a measure of hepatic acute-phase response. The Dental Arteriosclerosis Risk in Communities (ARIC) study, a cross-sectional study of the relationship between periodontal disease and cardiovascular disease, forms the basis for the examples used in this investigation.

RESULTS

Our findings demonstrated that while attachment loss, probing depth, (PD) and bleeding on probing (BOP) are individually associated with sICAM and CRP, only BOP remains significant for sICAM when all 3 are in the model and, for CRP, only PD remains significant. Both of these clinical parameters were more robust in estimating the degree of systemic inflammation than traditional classifications of mild, moderate, and severe periodontitis or other measures of disease severity such as attachment loss.

CONCLUSIONS

When selecting a definition of "systemic periodontitis" (periodontal disease that represents an exposure for a systemic condition), it is helpful to think of periodontal disease as a chronic oral infection with a number of clinical signs, rather than as the dento-centrically defined entity, periodontal disease. Thus, "systemic periodontitis" should be defined predicated upon those clinical signs that best represent the underlying mechanisms and temporal sequence that may affect that systemic outcome.

Coping with stress: its influence on periodontal disease

BACKGROUND

Various forms of stress behavior were documented and in patients with periodontitis their relationship with periodontal disease was investigated.

METHODS

Eighty-nine patients with different forms of chronic periodontitis were included in this retrospective case-control study. They were all undergoing periodontal treatment at the Department of Dental Prosthetics, University of Graz, or a private dental practice. The control group consisted of 63 persons employed in health care at the Clinic of Graz. All participants completed a stress coping questionnaire of 114 items and 19 actional and intrapsychic stress coping modes. The questionnaire served as a psychodiagnostic survey aimed at collecting data on stress coping strategies. Clinical attachment loss (CAL) served as the clinical parameter.

RESULTS

With the help of a factor analysis with a factorization and Varimax rotation, 5 factors were extracted from the 19 subtests. The reliability of the questionnaire was less than 0.70 only for subtests "escape" and "pharmaceutical drugs." Otherwise the internal consistency ranged between 0.74 and 0.92, and the retest reliability between 0.72 and 0.84. Subsequent assessment with the t test for independent random samples at the 5% level showed that patients differ significantly from controls in regard of factor 2 (active coping, P = 0.40) and 3 (distractive coping, P = 0.033), and that they differ very significantly from controls in regard of factor 4 (defensive coping, P = 0.000) and 5 (coping through aggression and pharmaceutical drugs, P = 0.007). In the statistical analysis of factors with regard to the severity of periodontal disease, the patients were divided into 2 groups (mild to moderate and severe). The t test for independent random samples showed significance for factor 4 (defensive coping) in that patients with a defensive coping style had greater attachment loss (pF4 = 0.04).

CONCLUSIONS

The data corroborate the thesis that periodontitis patients with inadequate stress behavior strategies (defensive coping) are at greater risk for severe periodontal disease. However, further investigations are required to confirm the significance of inappropriate coping styles with respect to the advancement of periodontal disease.

Root surface area of the mandibular cuspid and bicuspids

BACKGROUND

The purpose of this study was to determine the total root surface area of extracted teeth by computerized image analysis and the amount of remaining attachment area assuming various amounts of bone loss due to periodontal disease.

METHODS

One hundred fifty extracted mandibular teeth were evaluated, and measured from cusp tip to the cemento-enamel junction (CEJ), CEJ to root apex, and cusp tip to root apex. The fulcrum point of the tooth was also measured, along with the total root surface area of attachment and total surface area of attachment remaining following simulation of attachment loss in 2 mm increments. Measurements were made on 80 teeth on one proximal surface and either the buccal or lingual surface and multiplied by a factor of 2. Measurements on 70 teeth were made on all 4 root surfaces to predict the accuracy of measuring only 2 surfaces to determine root surface area. Images of the tooth surfaces were obtained by video camera and converted to computer image with measurement of the surface areas.

RESULTS

The total root surface area for the mandibular cuspids and first and second bicuspids was 275.88 mm2, 251.45 mm2, and 271.81 mm2, respectively. The 2-sided and 4-sided measurements for the mandibular first bicuspid were 252.55 mm2 and 247.02 mm2, respectively (P>0.05).

CONCLUSIONS

This study found the total root surface area to be greater than that in most previous studies. Increasing attachment loss is related to decreasing root surface area; however, this relationship is not directly proportional. No statistical difference was found between measuring 4 surfaces versus only 2 surfaces.

Antibody-based diagnostic for 'refractory' periodontitis

OBJECTIVE

About 10-15% of US adults are 'refractory' to therapy for chronic periodontitis. Recently, studies suggest that these patients have elevated lysine decarboxylase activity in the sulcular microbiota. The aim of this study was to determine whether an elevated IgG antibody response to lysine decarboxylase, alone or with antibody to other bacterial antigens and baseline clinical measurements, would predict 'refractory' patients with high accuracy.

METHODS

Chronic periodontitis patients were treated using scaling and root planing (SRP) followed by maintenance SRP and 3-monthly re-examinations. If there was a loss of mean full mouth attachment or more than three sites appeared with > 2.5 mm new loss within a year, the subjects were re-treated (modified Widman flap surgery and systemically administered tetracycline). If attachment loss as above recurred, the subjects were 'refractory'. Baseline clinical measurements and specific antibody responses were used in a logistic regression model to predict 'refractory' subjects.

RESULTS

Antibody to a peptide portion of lysine decarboxylase (HKL-Ab) and baseline bleeding on probing (BOP) prevalence measurements predicted attachment loss 3 months after initial therapy [pIAL = loss (0) or gain (1)]. IgG antibody contents to a purified antigen from Actinomyces spp. (A-Ab) and streptococcal d-alanyl glycerol lipoteichoic acid (S-Ab) were related in 'refractory' patients (R2 = 0.37, p < 0.01). From the regression equation, the relationship between the antibodies was defined as linear (pLA/S-Ab = 0) or non-linear pLA/S-Ab = 1). Using pLA/S-Ab, pIAL and age, a logistic regression equation was derived from 48 of the patients. Of 59 subjects, 37 had 2-4 mm attachment loss and were assigned as 'refractory' or successfully treated with 86% accuracy.

CONCLUSION

HKL-Ab facilitated an accurate prediction of therapeutic outcome in subjects with moderate periodontitis.

Effects of hippocampal lesioning on experimental periodontitis in Wistar rats

The hippocampus, which is a brain structure involved in learning and memory processes, plays a key role in the feedback regulation of the hypothalamic-pituitary-adrenal (HPA) axis and autonomic sympathetic nervous system, and the subsequent secretion of immuno-modulatory hormones in response to pathogenic microorganisms. Dysregulation of these brain-neuroendocrine-immune regulatory networks, which act in concert to maintain homeostasis, is found to be of critical importance to the host defence against pathogens, as well as susceptibility to diseases, including periodontal disease. The present study was designed to determine the effects of hippocampal lesioning on the progression of periodontitis. Experimental ligature-induced periodontitis was induced in 16 Wistar rats, which were bilaterally lesioned in their hippocampal region with an aspiration technique that is well documented to impair learning and memory, as well as in 15 sham-operated control rats. The disease progression was evaluated radiographically and histometrically. The results revealed that the hippocampal lesioned rats developed significantly more destruction of the periodontium than did the sham-operated controls. This finding supports recent studies that indicate that inappropriate brain-neuroendocrine regulation of inflammatory responses to infectious agents may play an important role in disease susceptibility and progression.

Periodontal attachment level of extractions presumably performed for periodontal reasons

BACKGROUND/AIMS

The aim of this study was to analyse the residual periodontal attachment in teeth extracted by East German dentists in order to determine a possible 'forceps level'.

METHODS

Out of about 8000 extracted teeth collected from a dental waste disposal company, 500 teeth were randomly selected. After exclusion of wisdom teeth and premolars extracted for orthodontic reasons (intact teeth with attachment > 90%), coronal and root caries, fillings, pulp exposure and incomplete root fillings (based on X-rays) were registered. The periodontal ligament was stained with 1% Fuchsin Red and measured with a light microscope.

RESULTS

For intact teeth (DF = 0, periodontal disease definition I), the mean periodontal attachment (50.5% +/- 16.0) was significantly lower than for teeth with carious defects or fillings (64.7% +/- 18.8. unpaired t-test: p < 0. 00 1). There was a marked increase in frequency of extractions in intact teeth below 70% periodontal attachment and 37% were extracted at attachment levels between 50 and 69%. Teeth with pulpal involvement showed significantly different frequency distributions and mean attachment values (77.9% +/- 17.8) than the remaining teeth (periodontal disease definition II; 55,2% +/- 15.5).

CONCLUSIONS

A considerable number of teeth with no or minor coronal destruction were extracted at an attachment level of 50-70%, regardless of the tooth type. The threshold for 'periodontal' extractions seem to be too low and undifferentiated, which calls for an improvement in knowledge of periodontal diagnosis and treatment.

Prevalence of aggressive periodontitis in school attendees in Uganda

AIM

The prevalence and severity of early onset periodontitis (EOP) among students attending secondary schools in two regions of Uganda was studied.

MATERIAL AND METHODS

690 students (393 males and 297 females) aged 12-25 years (mean 17 years), representing a range of tribal groups, were recruited from six schools in the peri-urban Central and rural Western regions of Uganda. The study subjects were clinically examined in field conditions by a single calibrated examiner to measure gingival recession and probing depth at six sites per tooth, with subsequent calculation of clinical periodontal attachment level for each site. Subjects exhibiting >or= 4 mm of clinical periodontal attachment loss at approximal surfaces of one or more teeth were classified with EOP. A structured written questionnaire obtained demographic characteristics of the study subjects.

RESULTS

199 (28.8%) study subjects showed clinical features of EOP, of which 16 (2.3%) subjects exhibited generalized EOP, 29 (4.2%) localized EOP, and 154 (22.3%) incidental EOP. The percentage of EOP-affected males was significantly higher than females (33.8% vs. 22.2%, P < 0.001). EOP prevalence tended to increase with increasing age, but no association was found between EOP prevalence and socioeconomic status or residency in urban vs. rural areas of Uganda. Molars and mandibular incisors generally demonstrated the highest occurrence of >or= 4 mm attachment loss. Clinical periodontal attachment loss of >or= 5 mm was mainly seen at first molars and incisors, suggesting that these two tooth types are first affected with attachment loss. Approximal tooth surfaces showed greater probing depth and attachment loss than buccal and lingual surfaces. Gingival recession was most prevalent at mandibular anterior teeth, whereas gingival margin coronal to CEJ was most frequently observed at second molars and maxillary incisors.

CONCLUSION

A relatively high prevalence of EOP (28.8%) was found in young Ugandan school attendees, with 6.5% of these showing severe disease. EOP in Uganda was significantly more prevalent in males than females, and most frequently characterized by approximal involvement of molars and mandibular incisors. Etiologic and predisposing factors associated with the high occurrence of EOP in Uganda, as well as therapeutic and preventive measures of the disease in this population, remain to be delineated.