Neutrophil functional activity in juvenile and adult onset diabetic patients with mild and severe periodontitis

Interplay between diabetes mellitus and periodontal/pulpal-periapical diseases

This longevity of life expectancy has indirectly led to an increase in the number of chronic diseases such as periodontitis, apical periodontitis (AP), and diabetes mellitus (DM) in the aging society, thus affecting people's quality of life. There is an interaction between periodontitis/AP and DM with a two-way relationship. Although type 1 and 2 diabetes (T1DM, T2DM) have different etiologies, glycemic control may affect the infection, inflammation and tissue healing of periodontitis and AP. Non-surgical periodontal treatment may influence the glycemic control as shown by decrease of HbA1c level in T2DM patient. However, the effect of periodontal treatment on glycemic control in T1DM and root canal treatment/apical surgery on T1DM and T2DM patients awaits investigation. DM may affect the periodontal and periapical tissues possibly via altered oral microbiota, impairment of neutrophils' activity and host immune responses and cytokine production, induction of oxidative stress etc. While periodontitis associated systemic inflammation and hyperlipidemia is suggested to contribute to the control of T2DM, more intricate studies are necessary to clarify the detailed mechanisms. The interactions between DM (T1DM and T2DM) and periodontitis and AP are therefore reviewed to provide a basis for the treatment of subsequent patients with pulpal/periodontal disease and diabetes. A two-pronged approach of medical and dental treatment is needed for the management of these patients, with emphasis on blood glucose control and improving oral hygiene and periodontal maintenance care, to ensure the best treatment outcome.

The impact of diabetes on periodontal diseases

The susceptibility and severity of periodontal diseases is made more severe by diabetes, with the impact on the disease process inversely proportional to the level of glycemic control. Although type 1 diabetes mellitus and type 2 diabetes mellitus have different etiologies, and their impact on bone is not identical, they share many of the same complications. Studies in animals and humans agree that both forms of diabetes increase inflammatory events in periodontal tissue, impair new bone formation, and increase expression of RANKL in response to bacterial challenge. High levels of glucose, reactive oxygen species, and advanced glycation end-products are found in the periodontium of diabetic individuals and lead to increased activation of nuclear factor-kappa B and expression of inflammatory cytokines such as tumor necrosis factor and interleukin-1. Studies in animals, moreover, suggest that there are multiple cell types in periodontal tissues that are affected by diabetes, including leukocytes, vascular cells, mesenchymal stem cells, periodontal ligament fibroblasts, osteoblasts, and osteocytes. The etiology of periodontal disease involves the host response to bacterial challenge that is affected by diabetes, which increases the expression of RANKL and reduces coupled bone formation. In addition, the inflammatory response also modifies the oral microbiota to render it more pathogenic, as demonstrated by increased inflammation and bone loss in animals where bacteria are transferred from diabetic donors to germ-free hosts compared with transfer from normoglycemic donors. This approach has the advantage of not relying upon limited knowledge of the specific bacterial taxa to determine pathogenicity, and examines the overall impact of the microbiota rather than the presumed pathogenicity of a few bacterial groups. Thus, animal studies have provided new insights into pathogenic mechanisms that identify cause-and-effect relationships that are difficult to perform in human studies.

Risk factors for periodontal disease

Risk factors play an important role in an individual's response to periodontal infection. Identification of these risk factors helps to target patients for prevention and treatment, with modification of risk factors critical to the control of periodontal disease. Shifts in our understanding of periodontal disease prevalence, and advances in scientific methodology and statistical analysis in the last few decades, have allowed identification of several major systemic risk factors for periodontal disease. The first change in our thinking was the understanding that periodontal disease is not universal, but that severe forms are found only in a portion of the adult population who show abnormal susceptibility. Analysis of risk factors and the ability to statistically adjust and stratify populations to eliminate the effects of confounding factors have allowed identification of independent risk factors. These independent but modifiable, risk factors for periodontal disease include lifestyle factors, such as smoking and alcohol consumption. They also include diseases and unhealthy conditions such as diabetes mellitus, obesity, metabolic syndrome, osteoporosis, and low dietary calcium and vitamin D. These risk factors are modifiable and their management is a major component of the contemporary care of many periodontal patients. Genetic factors also play a role in periodontal disease and allow one to target individuals for prevention and early detection. The role of genetic factors in aggressive periodontitis is clear. However, although genetic factors (i.e., specific genes) are strongly suspected to have an association with chronic adult periodontitis, there is as yet no clear evidence for this in the general population. It is important to pursue efforts to identify genetic factors associated with chronic periodontitis because such factors have potential in identifying patients who have a high susceptibility for development of this disease. Many of the systemic risk factors for periodontal disease, such as smoking, diabetes and obesity, and osteoporosis in postmenopausal women, are relatively common and can be expected to affect most patients with periodontal disease seen in clinics and dental practices. Hence, risk factor identification and management has become a key component of care for periodontal patients.

Diabetes, periodontitis, and the subgingival microbiota

Both type 1 and type 2 diabetes have been associated with increased severity of periodontal disease for many years. More recently, the impact of periodontal disease on glycaemic control has been investigated. The role of the oral microbiota in this two-way relationship is at this stage unknown. Further studies, of a longitudinal nature and investigating a wider array of bacterial species, are required in order to conclusively determine if there is a difference in the oral microbiota of diabetics and non-diabetics and whether this difference accounts, on the one hand, for the increased severity of periodontal disease and on the other for the poorer glycaemic control seen in diabetics.

Mapping the pathogenesis of periodontitis: a new look

Chronic adult periodontitis is a bacterially induced chronic inflammatory disease that destroys the connective tissue and bone that support teeth. Concepts of the specific mechanisms involved in the disease have evolved with new technologies and knowledge. Histopathologic observations of diseased human tissues were used previously to speculate on the causes of periodontitis and to describe models of pathogenesis. Experimental evidence later emerged to implicate bacterial plaque deposits as the primary factor initiating periodontitis. At the same time, specific bacteria and immunoinflammatory mechanisms were differentially implicated in the disease. In the mid-1990s, early insights about complex diseases, such as periodontitis, led to new conceptual models of the pathogenesis of periodontitis. Those models included the bacterial activation of immunoinflammatory mechanisms, some of which targeted control of the bacterial challenge and others that had adverse effects on bone and connective tissue remodeling. Such models also acknowledged that different environmental and genetic factors modified the clinical phenotype of periodontal disease. However, the models did not capture the dynamic nature of the biochemical processes, i.e., that innate differences among individuals and changes in environmental factors may accelerate biochemical changes or dampen that shift. With emerging genomic, proteomic, and metabolomic data and systems biology tools for interpreting data, it is now possible to begin describing the basic elements of a new model of pathogenesis. Such a model incorporates gene, protein, and metabolite data into dynamic biologic networks that include disease-initiating and -resolving mechanisms. This type of model has a multilevel framework in which the biochemical networks that are regulated by innate and environmental factors can be described and the interrelatedness of networks can be captured. New models in the next few years will be merely frameworks for integrating key knowledge as it becomes available from the "-omics" technologies. However, it is possible to describe some of the key elements of the new models and discuss distinctions between the new and older models. It is hoped that improved conceptual models of pathogenesis will assist in focusing new research and speed the translation of new data into practical applications.

Expression of matrix metalloproteinases (MMP-8 and -9) in chronic periodontitis patients with and without diabetes mellitus

BACKGROUND

Matrix metalloproteinases (MMPs) are involved in a number of physiological events, and they are the major players in collagen breakdown during periodontal tissue destruction. Diabetes mellitus (DM) has been associated with altered collagen metabolism and increases the response of the periodontal tissue to pathogenic microorganisms, thereby increasing the severity of periodontal disease. The aim of this study was to assess the expression of MMP-8 and -9 in gingival tissues of diabetic chronic periodontitis (CP), non-diabetic CP, and healthy patients.

METHODS

The plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) were assessed. The levels of MMP expression in gingival tissue extracts were measured by gelatin zymography and Western blotting. The structural changes in tissues were analyzed by histological examination and collagen estimation.

RESULTS

Higher levels of PI, GI, CAL, and deeper PD were observed in CP patients with DM than CP patients without DM. The average concentration of MMP-9 was increased three-fold, and the MMP-8 was increased two-fold in CP patients with DM compared to CP patients without DM. A high infiltration of inflammatory cells and less collagen were observed in the histologic analysis of gingival biopsies from diabetic patients.

CONCLUSIONS

An increased concentration of MMP-8 and -9 in the gingival tissue of diabetic CP patients suggests that the expression of these MMPs contributes to the failure of the healing process in the diabetic condition. Treatment strategies directed toward the inhibition of these MMPs could lead to an improved healing rate in CP patients.

Periodontal disease in pregnancy complicated by type 1 diabetes mellitus

BACKGROUND

Systemic disease and hormonal changes have been implicated as complicating factors for periodontal disease. Diabetes has been identified as a risk factor for periodontal disease, and diabetics can experience periodontal destruction at an earlier age than non-diabetic individuals. Increased hormone levels during pregnancy can contribute to increased gingival inflammation. The purpose of this study was to examine the association of type 1 diabetes mellitus (DM) on the periodontal status of pregnant women.

METHODS

Thirty-three (13 diabetic and 20 non-diabetic) subjects, 20 to 39 weeks gestation, participated in this study. The mean age of the diabetics and non-diabetics was 28.5 +/- 7.1 (SD) and 27.0 +/- 7.3 years, respectively. The following parameters were assessed at Ramfjord's reference teeth: plaque index (PI), gingival inflammation (GI), probing depth (PD), gingival margin (GM) location, and clinical attachment level (CAL).

RESULTS

Diabetic subjects had significantly (P<0.001) higher PI (1.48 +/- 0.69) and GI (1.77 +/- 0.44) scores than non-diabetics (PI = 0.63 +/- 0.38; GI = 0.93 +/- 0.48). Mean PD for diabetics (2.95 +/- 0.69 mm) was significantly different (P<0.024) from that of non-diabetics (2.44 +/- 0.32 mm). Although mean GM location was coronal to the cemento-enamel junction (CEJ) in both groups, gingival margins were at a more apical position (P<0.001) in the diabetics (-0.20 +/- 1.24 mm) compared to non-diabetics (-1.76 +/- 0.53 mm). Mean CAL values also varied significantly (P<0.001) between diabetics (2.60 +/- 1.54 mm) and non-diabetics (0.68 +/- 0.65 mm). Significant differences were seen for GI (P<0.001), PD (P=0.005), GM location (P<0.001), and CAL (P<0.001) when assessing the effect of diabetes and controlling for plaque. When assessing the effect of plaque and controlling for diabetes, the only significant difference was GI (P=0.001).

CONCLUSIONS

The results of this study demonstrate that periodontal inflammation and destruction are increased in pregnant diabetics as compared to non-diabetic pregnant patients. These findings may have implications for diabetic control and, hence, maternal and fetal outcomes in pregnant diabetic patients.

Localized aggressive periodontitis in a patient with type 1 diabetes mellitus: a case report

BACKGROUND

Poor metabolic control of diabetes mellitus (DM) has often been associated with the severity of periodontal disease. The aim of this report is to present a 9-year-old female with localized aggressive periodontitis who had a history of type 1 DM and the outcome of her treatment.

METHODS

The patient had received medical, clinical, and radiographic periodontal examinations. Peripheral blood analysis was done as well. She had non-surgical periodontal treatment, and medical management of her diabetes was performed at the same time. She was followed longitudinally for 5 years.

RESULTS

Medical examination revealed no pathological findings except for growth retardation. Laboratory tests showed that she had poor metabolic control, with 497 mg/dl fasting blood glucose and 15.6% HbA1c. The random migration and neutrophil chemotaxis were significantly reduced. Periodontal treatment and metabolic control of her diabetes resulted in significant improvement in her periodontal condition. No incipient periodontal breakdown was observed around the teeth after 5 years from baseline.

CONCLUSIONS

This report proves the efficiency of periodontal therapy in the prevention of future periodontal breakdown in a systemically compromised patient. It seems that in certain individuals who are predisposed to the aggressive forms of periodontitis, clinical and medical examinations and intervention to the systemic condition, in combination with periodontal treatment, are important in the management of these individuals.

The effect of periodontal treatment on glycemic control in patients with type 2 diabetes mellitus

BACKGROUND, AIMS

This study was designed to explore the effect of periodontal therapy on glycemic control in persons with type 2 diabetes mellitus (DM).

METHODS

36 patients with type 2 DM (treatment group) received therapy for adult periodontitis during an 18-month period. A 36-person control group was randomly selected from the same population of persons with type 2 DM who did not receive periodontal treatment.

RESULTS

These groups were well matched for most of the parameters investigated. During the nine-month observation period, there was a 6.7% improvement in glycemic control in the control group when compared to a 17.1% improvement in the treatment group, a statistically significant difference. Several parameters that could confound or moderate this glycemic control were explored. These included the treatment of non-dental infections, weight and medication changes. No moderating effect was associated with any of these variables. However, there were too few subjects in the study to have the statistical power necessary to assess these possible moderators of glycemic control.

CONCLUSIONS

We interpret the data in the study to suggest that periodontal therapy was associated with improved glycemic control in persons with type 2 DM.

Diabetes and periodontal diseases. Committee on Research, Science and Therapy. American Academy of Periodontology

This position paper on diabetes mellitus was prepared by the Research, Science and Therapy Committee of The American Academy of Periodontology. It is intended to: 1) update members of the dental profession on the diagnosis and medical management of patients with diabetes mellitus; 2) summarize current knowledge on the relation between diabetes mellitus and periodontal diseases; 3) provide an overview of factors in diabetic patients relevant to understanding the pathogenesis of periodontal diseases in these subjects; 4) outline special considerations associated with treatment of periodontal diseases in diabetic patients; and 5) discuss possible approaches to the management of diabetic emergencies in the dental office.

Diabetes and periodontal diseases

This position paper on diabetes mellitus was prepared by the Research, Science and Therapy Committee of The American Academy of Periodontology. It is intended to: 1) update members of the dental profession on the diagnosis and medical management of patients with diabetes mellitus; 2) summarize current knowledge on the relation between diabetes mellitus and periodontal diseases; 3) provide an overview of factors in diabetic patients relevant to understanding the pathogenesis of periodontal diseases in these subjects; 4) outline special considerations associated with treatment of periodontal diseases in diabetic patients; and 5) discuss possible approaches to the management of diabetic emergencies in the dental office.

An immunological evaluation of type II diabetic patients with periodontal disease

Peridontal disease is a frequent complication of diabetes, and diabetic subjects often exhibit decreased immune response with increased susceptibility to infection. We evaluated the possible relationship between immune response and periodontal disease in 40 type II diabetic patients, mean (+/- SD) age 59 +/- 8 years and mean disease duration 17 +/- 4 years, with good metabolic control (mean fasting plasma glucose, 10.5 +/- 3.8 mM/L, mean HbA1c 8.1 +/- 1.66%), and in 40 age and gender-matched controls. Interproximal alveolar bone loss (ABL), as the percentage of bone loss from the cement enamel junction (CEJ) to the apex, was measured with a modified Schei ruler at the deepest point on the mesial/distal surface of the teeth, except third molars, on a panoramic radiograph. Immunological evaluation involved study of NADPH neutrophil superoxide production, neutrophil chemotaxis, lymphocyte subpopulations, immunoglobulins and complement. Diabetic patients showed significant differences compared with controls regarding ABL (30.6 +/- 14.7% versus 17.6 +/- 4.3%; p < 0.0001) and the T-helper/T-suppressor ratio (2.3 +/- 1.0% versus 1.8 +/- 0.8%; p < 0.05). Other parameters of cell-mediated immunity and humoral immune response did not show any significant variations. No correlation between immunological and radiographic analysis parameters were found. Further studies are needed to verify the exact role played by immunological factors in type II diabetic patients with periodontal disease.

Periodontal disease as a complication of diabetes mellitus

Based on our clinical observations that patients with insulin-dependent diabetes mellitus (IDDM) are subject to periodontal disease, we developed the hypothesis that hyper- or hypoglycemia might contribute to the pathogenesis of diabetic periodontitis. In this article, experimental facts that substantiate this hypothesis are presented on the basis of our studies and then discussed. Hyperglycemia progressively glycates body proteins, forming advanced glycation end products (AGE), which stimulate phagocytes to release inflammatory cytokines such as TNF-alpha and IL-6. In this context, to understand the effects of hyperglycemic episodes on periodontal health, 24 adolescent IDDM patients were examined for their periodontal status, and 3 of them were found to have periodontitis. Laboratory analyses on these 3 patients revealed that 2 had elevated serum TNF-alpha levels. These results may partly support the current hypothesis of a mechanism of diabetic complications in which abnormal cytokine levels induced by AGE could exacerbate inflammatory responses. In IDDM patients, the diabetes is often accompanied not only by hyperglycemic episodes but also by iatrogenic hypoglycemia. Periodontal ligament cells (PDL) cultured under hyperglycemic conditions were impaired in such biological functions as adhesion and motility, while cells cultured under hypoglycemic conditions (10 mg/dL) gradually dissociated from their anchor and underwent cell death. These phenomena correlated well with the expression profile of fibronectin receptor. Interestingly, these changes due to the different glucose levels were observed more intensively in PDL than in other fibroblastic cells, suggesting that the biological functions of PDL are easily led to impairment by variation or rapid fluctuation of glucose levels. These observations suggest that hyperglycemia could indirectly exacerbate inflammatory tissue destruction through the body's scavenger system against AGE, and that both hyper- and hypoglycemia might directly impair the biological functions of periodontal connective tissues through cell-matrix interactions.

Advanced glycation endproducts (AGEs) induce oxidant stress in the gingiva: a potential mechanism underlying accelerated periodontal disease associated with diabetes

We hypothesized that one mechanism underlying advanced periodontal disease in diabetes may involve oxidant stress in the gingiva, induced by the effects of Advanced Glycation Endproducts (AGEs), the irreversible products of non-enzymatic glycation and oxidation of proteins and lipids which accumulate in diabetic plasma and tissue. Infusion of AGE albumin, a prototypic ligand, into mice resulted in increased generation of thiobarbituric acid reactive substances (TBARS) compared with infusion of non-glycated albumin in the gingiva, as well as in the lung, kidney and brain. Pretreatment of the animals with the antioxidants probucol or N-acetylcysteine (NAC) prevented the generation of TBARS in the gingiva. Affinity-purified antibody to AGEs demonstrated increased immunoreactivity for AGEs in the vasculature and connective tissues of the gingiva in streptozotocin-induced diabetic mice compared to non-diabetic controls. Increased immunoreactivity for AGEs was also demonstrated in the gingiva of diabetic humans compared with non-diabetic individuals via immunohistochemistry and ELISA. Consistent with these data, immunohistochemistry for heme oxygenase-1, a marker of enhanced oxidant stress, was increased in the gingival vasculature of diabetic mice and humans compared with non-diabetic controls. These data suggest that AGEs present in diabetic gingiva may be associated with a state of enhanced oxidant stress, a potential mechanism for accelerated tissue injury.

The alterations of whole saliva constituents in patients with diabetes mellitus

The present study was undertaken in order to determine the possible alterations in whole saliva and the periodontal status in patients with diabetes mellitus (DM), and was conducted on 17 patients with DM and 17 systemically and periodontally healthy subjects. When the subjects were evaluated clinically, significantly increased probing depths were noticed in the DM group when compared with the healthy subjects. In whole saliva samples, sodium, potassium, total protein, amylase, thiocyanate, and secretory IgA levels were determined in both groups. Difference between the two groups regarding the mean salivary potassium levels were found to be statistically significant since the mean salivary potassium levels in the DM and the control groups were 2.470 +/- 9.04 mmol/L and 14.30 +/- 8.88 mmol/L, respectively. The mean salivary total protein, amylase and secretory IgA levels in the DM group were 2.41 +/- 1.0 mg/mL, 124.2 +/- 79.7 U/mL and 6.86 +/- 3.50 mg/L, all being significantly higher than the control group. However, no significant differences could be shown for the salivary sodium and thiocyanate levels. Nor was there any difference between non-insulin dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM). The findings of the present study suggest that, besides the clinical examinations, the determination of the possible alterations in the composition of whole saliva might also be helpful in understanding the increased severity of periodontal disease in diabetic patients.

Periodontal status and selected cultivable anaerobic microflora of insulin-dependent juvenile diabetics

The periodontal status and subgingival microflora of insulin-dependent juvenile diabetic (JD) patients (n = 16, mean age = 11.3) were compared with that of their non-diabetic cohabiting healthy siblings (HS, n = 16, mean age = 13.2). JD patients were monitored every 3 months for levels of glycosylated hemoglobin (HbA1c) and clinical and microbial parameters were measured 6 weeks before drawing blood for levels of HbA1c (M% = 8.76). Clinical indices, measured for the entire permanent dentition, included: probing depth (PD), attachment level (AL), sulcus bleeding index (SBI), and plaque index (PI). Subgingival plaque samples were obtained at 2 sites from each subject; whenever possible, the site with the deepest probing depth and the mesial aspect of the maxillary right first molar were used. Microbial analyses were determined by cultural characteristics and biochemical tests. No significant differences were detected in any of the clinical indices for the entire dentition. The mean AL for JD sites was 2.32 +/- 0.83 mm and for HS sites was 2.2 +/- 0.85 mm. Mean percentage of total cultivable anaerobic microflora included Capnocytophaga spp. (JD, 13.21%; HS, 11%) and Porphyromonas gingivalis (JD, 5.1%; HS, 7.9%). Differences between the two groups were not statistically significant. When cluster analysis was performed on sampled sites, one cluster group in JD patients showed significantly elevated P. gingivalis and lower Capnocytophaga spp. levels as compared to the overall mean. The clinical parameters of this cluster were characterized by statistically significant greater loss of attachment and probing depth. These data would suggest few differences between JD patients and their HS in this population.

Some suspected periodontopathogens and serum antibody response in adult long-duration insulin-dependent diabetics

The subgingival microflora and serum antibody response were examined in long-duration insulin-dependent diabetics and age- and sex-matched non-diabetics. The material consisted of 9 diabetics aged 40-49 years and 19 aged 50-59 years, 13 non-diabetics aged 40-49 years and 21 aged 50-59 years. The bacterial species studied (Actinobacillus actinomycetemcomitans, Campylobacter rectus, Capnocytophaga spp, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia) were recovered in diabetics as well as in non-diabetics. Significantly more diabetics in both age groups harboured P. gingivalis compared to non-diabetics. Prevalence of P. gingivalis was associated with deepened periodontal pockets among non-diabetics but not among diabetics. In diabetics and non-diabetics, the serum antibody titres for most antigens were similar.

Improved metabolic control, clinical periodontal status and subgingival microbiology in insulin-dependent diabetes mellitus. A prospective study

The effect of improved metabolic control on the clinical periodontal condition and the subgingival microflora of diseased and healthy periodontal pockets in 6 ambulatory insulin-dependent diabetes mellitus (IDDM) patients was prospectively studied. Duplicate measurements with a time-interval of 3 days were made every 4 moths for assessment of the metabolic status, the clinical periodontal condition and the subgingival microflora. During the study, patients maintained personal oral hygiene measures as they usually did before the study. Neither supplementary dental prophylaxis nor oral hygiene measures were applied during the investigation. Long-term metabolic control (HbAlc) improved significantly with intensive conventional insulin treatment. Gingival redness decreased significantly whereas gingival swelling showed a not significant trend to decrease. It is suggested that microvascular changes associated with improved metabolic control in diabetes mellitus may mediate the observed change in gingival redness. No effect could be demonstrated for probing pocket depth, probing attachment level, bleeding on probing and the plaque index. Statistical analysis of the effect of improved metabolic control on the subgingival microflora revealed that only the % of streptococci increased significantly in diseased periodontal pockets. In general, no significant changes were found in either healthy or diseased pockets with regard to the bacterial flora associated with periodontal disease. The results of the present study indicate that improved metabolic control in IDDM patients may have no potential impetus for an improved clinical periodontal condition nor on the subgingival bacterial flora. It is concluded that the periodontal condition in IDDM patients may only ameliorate when local oral hygiene measures are applied.

Neutrophil function and oral disease

The pathological sequela of reduced neutrophil function in the oral cavity and the mechanisms behind dysfunction have added to our understanding of infectious diseases. Numerous examples have been given, and the overriding conclusion must be that any impairment of neutrophil function will lead to some degree of increased susceptibility to infection. Perhaps the tissue most sensitive to pathological changes in the oral cavity is the periodontium. In cases of severe neutrophil dysfunction, there is severe periodontal breakdown, but also in cases of "mild" neutrophil dysfunction, where there is no other infection, such as in individuals with LJP, there is severe periodontal breakdown. The molecular basis of neutrophil dysfunction is beginning to be understood in individuals with LJP, LAD, CGD, and AIDS. It is our hope that further research in this area will help to delineate the pathogenesis of these and other oral diseases.

Relationship between bleeding/plaque ratio, family history of diabetes mellitus and impaired glucose tolerance

In the present study, the relationship between bleeding/plaque ratio, family history of diabetes mellitus and oral glucose tolerance pattern were investigated in 85 non-diabetic individuals without periodontal breakdown. In this group, no relationship between bleeding/plaque ratio, family history of diabetes mellitus and impaired glucose tolerance was found. The results of the present study suggest that the observed variation in bleeding/plaque ratio cannot be explained by impaired glucose tolerance or family history of diabetes mellitus. It is hypothesized that in subjects with impaired glucose tolerance, the periods of elevated blood glucose values may be too short to introduce tissue changes.

Leucocyte function in rats with naturally occurring gingivitis

The severity of gingivitis in relation to abnormal macrophage chemotaxis and superoxide (O2-) production was investigated in rats with naturally occurring gingivitis (plaque-susceptible rats). Macrophage chemotaxis was measured by the membrane filter method; zymosan-activated serum was used as a chemo-attractant. O2- production was measured by the reduction of cytochrome c method. Opsonized zymosan, phorbol myristate acetate and calcium ionophore A23187 were used as stimulants. The macrophage chemotaxis and O2- production in the plaque-susceptible rats with deep pockets were significantly lower than those in the susceptible rats with shallow pockets or the normal group. In addition, there was a negative correlation between the severity of gingivitis in plaque-susceptible rats and macrophage chemotaxis or O2- production. These findings suggest that impairement of the host defence mechanisms due to the reduction in macrophage chemotaxis and O2- production is related to the progression of periodontal disease in plaque-susceptible rats.

Refractory periodontitis: mixed infection with Bacteroides gingivalis and other unusual Bacteroides species. A case report

Host immune response and the predominant subgingival microflora were evaluated in a 47-year-old male exhibiting severe, recurrent periodontitis. The patient's neutrophils were chemotactically elevated but other functions were within normal limits. Significantly, Bacteroides gingivalis and Bacteroides zoogleoformans constituted 80% of the cultivable microflora and total cell count in subgingival plaque. The remainder of the cultivable microbiota was comprised of Fusobacterium nucleatum and Haemophillis aprophillis. The present study provides additional evidence for an association between B. gingivalis and severe, recurrent periodontal disease.

An unusual case of black teeth

Loss of enamel and a deep black stain of the teeth in a 40-year-old diabetic patient are strongly suggested to be caused by the daily consumption of a cheap white wine and, possibly, by the chewing of cayenne. The wine proved to be rather acid, thereby promoting abrasion as a result of gnashing, and to contain a high concentration of tannin. The exact role of the tannins is described.

1985 Kreshover lecture. Molecular factors influencing neutrophil defects in periodontal disease

Major advances in our understanding of the role of the neutrophil in host defense against periodontal organisms have been made through studies of localized juvenile periodontitis (LJP). Several lines of evidence suggest that LJP is an infectious process closely associated with Actinobacillus (Haemophilus) actinomycetemomitans as a causative agent, although other organisms may also participate. The immunologic profile of LJP patients suggests that a cell-associated neutrophil locomotory dysfunction is a key underlying immunodeficiency resulting in increased susceptibility to periodontal infection. In addition, LJP patients often exhibit cervical lymphadenopathy and IgG-hypergammaglobulinemia, and a markedly elevated antibody response to the infecting organism, A. actinomycetemcomitans, is found in the serum and crevicular fluid of most patients. Evaluation of the locomotory properties of LJP neutrophils shows that random migration and chemokinesis are normal; however, about 70% of the LJP patients suffer from a defect in chemotaxis, with their neutrophils responding poorly to bacterial chemotactic factors, synthetic chemotactic peptides, and complement fragments (C5a). Depressed chemotaxis of LJP neutrophils is paralleled by their reduced capacity to bind the synthetic chemotactic peptide N-formylmethionylleucylphenylalanine (FMLP), as well as C5a. Furthermore, there is a reduction in the amount of glycoprotein 110, a neutrophil membrane matrix component and differentiation antigen which is associated with FMLP- and possibly also C5a-mediated chemotaxis. Reduction of C5a and of FMLP ligand binding, decreased expression of GP-110, and reduced neutrophil chemotaxis are consistent with a stem cell maturation error in LJP patients. This is further supported by studies demonstrating increased expression of CR2, the C3d/EBV receptor, on peripheral blood neutrophils of LJP patients. CR2 receptors are normally present on immature human neutrophils but are lost during the maturation process. These alterations in neutrophil surface components and their reduced chemotaxis may result from a genetically determined abnormality. Studies demonstrating the familial nature of both the neutrophil chemotactic disorder and the clinical entity represented by localized juvenile periodontitis point to a strong role for genetic determinants in the disease which affect neutrophil surface receptors.

Neutrophil function and oral disease

The pathologic sequela of reduced neutrophil function have been reviewed. In each case, the mechanism for the reduction in function has been elaborated when known. Special emphasis has been placed upon the pathologic changes in the oral cavity as a result of neutrophil dysfunction. Numerous examples have been given, and the overriding conclusion must be that any impairment of neutrophil function will lead to some degree of increased susceptibility to infection. Perhaps the tissue most sensitive to pathologic changes in the oral cavity is the periodontium. In cases of severe neutrophil dysfunction there is severe periodontal breakdown. But also in cases of "mild" neutrophil dysfunction, where there is no other infection, such as in individuals with LJP, there is severe periodontal breakdown. The molecular basis of neutrophil dysfunction is beginning to be understood in individuals with LJP. It is our hope that further research in this area will help to delineate the pathogenesis of periodontal diseases.

Host responses in periodontal diseases

Great progress has been made in our understanding of the pathogenesis of periodontal disease, the primary role of bacteria as etiologic agents, and the critical modifying role of host responses. It is useful to consider several stages in the pathogenesis of periodontal disease - (a) colonization, (b) invasion, (c) destruction, and (d) healing - and to place into perspective the various host responses as they may affect each of these four stages (Table 5). With respect to colonization, although very little direct evidence is available, it is reasonable to suggest that antibodies, either secretory or serum-derived, acting by virtue of their ability to block attachment, could inhibit colonization by immune reduction of adherence mechanisms. With respect to invasion of the tissue, it appears that phagocytes, particularly the neutrophils, are important, acting in concert with opsonic antibody and complement in ingesting and killing the periodontal microflora before or during the early invasive process. A major advance in our understanding of the pathogenesis of periodontal diseases is the realization that the virulence of periodontopathic bacteria relates to their leukaggressive properties, allowing them to evade neutrophil protective mechanisms. Invasion of the periodontal tissues by bacterial products may be inhibited by the complexing of these products with antibody with the formation of antigen-antibody complexes that are phagocytosed and digested, particularly by scavenger phagocytes such as the macrophage. With respect to the destructive phase of periodontal disease, it is clear that the direct effect of lymphocytes mediated either through direct cytotoxic activity, or through biologically-active destructive lymphokines (such as alpha-lymphotoxin and osteoclast activating factor), can lead to tissue destruction. Macrophages, through the production of monokines, collagenase, and reactive oxygen species, can also lead to tissue destruction. The direct effects of bacterial toxins or enzymes which can lead to tissue destruction can be inhibited by complexing with antitoxic or enzyme-neutralizing antibodies. With respect to healing and fibrosis, very little direct information is available; however, it is possible that the lymphocytes and macrophages affect fibrosis by the production of chemotactic factors for fibroblasts which would be expected to bring them to the area of periodontal inflammation and also by production of fibroblast-activating factors, which then cause the fibroblasts to proliferate and produce collagen which replaces lost collagen or results in fibrosis.(ABSTRACT TRUNCATED AT 400 WORDS)