[Osteoclasts activation by bacterial endotoxins during periodontal diseases]

During periodontal infections, bacterial lipopolysaccharides (LPS) from Gram negative bacteria, along with other bacterial products, drive alveolar bone destruction. Tissue destruction occurs through both direct and indirect pathways. In the indirect pathway, LPS induce the secretion of proinflammatory cytokines, which in turn provokes a cascade of reactions leading to osteoclasts activation. In the direct pathway, LPS stimulate osteoblasts, osteoclasts precursors and osteoclasts, with an inflammatory cytokines independent manner. In this paper, the mechanisms involved in these two pathways are reviewed.

Periodontal health and oral mucosal lesions as related to occupational exposure to acid mists

OBJECTIVES

The association between exposure to acid mists and periodontal changes and oral mucosal lesions was measured using data from an Oral Health Promotion Program in a large metal plant. The role of sociodemographic factors, lifestyle, and oral health behavior in relation to these outcomes was also examined.

METHODS

This is a cross-sectional study of 665 active male workers who volunteered to participate in the oral health program. A job exposure matrix was constructed with industrial hygienist scores and job titles to estimate years of exposure to acid mists. Oral health outcomes were identified during standardized dental examinations. Unconditional logistic regression models were utilized in the analysis.

RESULTS

Duration of exposure to acid mists exposure was positively associated with oral mucosal lesions among workers without lip sealing. Only age, low salaries and oral hygiene-related variables were associated with periodontal changes, and estimates varied according to lip sealing.

CONCLUSIONS

Results suggest that long-term occupational exposure to acid mists is associated with oral mucosal lesions, and that absence of lip sealing may increase the intensity of exposure.

[Clinical aspects of the evolution of dental caries and periodontal disease in patients treated with corticosteroids]

Patients treated with adrenal glucocorticoids may run a higher risk of dental caries, both as a result of their medical condition and of the physical and physiological effects of their pharmacotherapy. Our clinical study reports about patients treated with glucocorticoids who were also having an odonto-periodontal condition. They were examined and we found rampant caries and periodontal diseases. The slow evolution of asymptomatic periodontal disease encouraged destruction of teeth in root caries. The rampant caries were correlated with immunodeficiency and treatment of these caries must take into account the general treatment.

Sugars and dental caries

A dynamic relation exists between sugars and oral health. Diet affects the integrity of the teeth; quantity, pH, and composition of the saliva; and plaque pH. Sugars and other fermentable carbohydrates, after being hydrolyzed by salivary amylase, provide substrate for the actions of oral bacteria, which in turn lower plaque and salivary pH. The resultant action is the beginning of tooth demineralization. Consumed sugars are naturally occurring or are added. Many factors in addition to sugars affect the caries process, including the form of food or fluid, the duration of exposure, nutrient composition, sequence of eating, salivary flow, presence of buffers, and oral hygiene. Studies have confirmed the direct relation between intake of dietary sugars and dental caries across the life span. Since the introduction of fluoride, the incidence of caries worldwide has decreased, despite increases in sugars consumption. Other dietary factors (eg, the presence of buffers in dairy products; the use of sugarless chewing gum, particularly gum containing xylitol; and the consumption of sugars as part of meals rather than between meals) may reduce the risk of caries. The primary public health measures for reducing caries risk, from a nutrition perspective, are the consumption of a balanced diet and adherence to dietary guidelines and the dietary reference intakes; from a dental perspective, the primary public health measures are the use of topical fluorides and consumption of fluoridated water.

Cardiovascular diseases and periodontology

BACKGROUND

Cardiovascular diseases represent a widespread heterogeneous group of conditions that have significant morbidity and mortality. The various diseases and their treatments can have an impact upon the periodontium and the delivery of periodontal care.

AIM

In this paper we consider three main topics and explore their relationship to the periodontist and the provision of periodontal treatment.

METHOD

The areas reviewed include the effect of cardiovascular drugs on the periodontium and management of patients with periodontal diseases; the risk of infective endocarditis arising from periodontal procedures; the inter-relationship between periodontal disease and coronary artery disease.

RESULTS AND CONCLUSIONS

Calcium-channel blockers and beta-adrenoceptor blockers cause gingival overgrowth and tooth demineralisation, respectively. Evidence suggests that stopping anticoagulant therapy prior to periodontal procedures is putting patients at a greater risk of thromboembolic disorders compared to the risk of prolonged bleeding. The relationship between dentistry and infective endocarditis remains a controversial issue. It would appear that spontaneous bacteraemia arising from a patient's oral hygiene practices is more likely to be the cause of endocarditis than one-off periodontal procedures. The efficacy of antibiotic prophylaxis is uncertain (and unlikely to be proven), and the risk of death from penicillin appears to be greater than the risk of death arising from infective endocarditis. Finally, the association between periodontal disease and coronary artery disease has been explored and there seem to be many issues with respect to data handling interpretation. Many putative mechanisms have been suggested; however, these only further highlight the need for intervention studies.

The role of soluble interleukin (IL)-6 receptor in mediating the effects of IL-6 on matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 expression by gingival fibroblasts

BACKGROUND

Interleukin-6 (IL-6) is a multifunctional cytokine thought to play a role in the tissue destruction that characterizes periodontal disease. IL-6 exerts its cellular effects through a cell-surface receptor which also exists in a soluble form (sIL-6r). This study investigated the effects of IL-6 on matrix metalloproteinase (MMP)-1 activity in gingival fibroblast cultures, specifically determining the role of the sIL-6r in mediating these actions.

METHODS

Fibroblasts were grown to confluence, washed in Hank's balanced saline solution (HBSS), and then cultured for 72 hours in serum-free medium supplemented with 0.2% bovine serum albumin, 1 microgram/ml Escherichia coli LPS and containing various combinations of IL-6 and its soluble receptor over the concentration range 0 to 1,000 ng/ml. MMP-1 and tissue inhibitor of MMP (TIMP)-1 protein levels in the conditioned medium were assessed by enzyme-linked immunosorbent assay (ELISA) and collagenolytic activity determined using a 3H-acetylated type I collagen degradation assay.

RESULTS

Results indicated that the addition of IL-6 alone to cultures, over the concentration range 0 to 1,000 ng/ml, had no significant effect on MMP-1 protein expression. However, addition of IL-6 in combination with its soluble receptor resulted in a statistically significant, dose-dependent upregulation in MMP-1 expression. The IL-6/sIL-6r combination also induced a significant increase in collagenolytic activity in cultures. IL-6 and sIL-6r, either alone or in combination, had no marked effect on TIMP expression or cell growth.

CONCLUSIONS

These data strongly suggest that future clinical studies investigating the role of IL-6 in periodontal disease must also determine the levels of sIL-6r within the periodontal tissues.

[Periodontal disease and general health--literature review]

Periodontal disease is a significant cause of alveolar bone resorption resulting ultimately in the loss of teeth. Inflammation of the periodontal tissues is initiated by bacteria of the oral micro-flora. Invading micro-organisms stimulate both protective and destructive inflammatory-immune responses involving cytokine release syndrome, chemokines, arachidonic acid metabolites, reactive oxygen and nitrogen intermediates, and matrix melloproteinases. The local infection may affect general health in two ways. First, transient bacteremia from the oral focus may result in metastatic infection in remote organs of susceptible hosts, such as bacterial endocarditis in patients with congenital or acquired heart diseases. Second, lipopolysaccharide and inflammatory mediators are not only involved in local tissue destruction but have the potential to modulate the course of cardiovascular, chronic obstructive lung and autoimmune diseases, diabetes mellitus and preterm birth. Epidemiologic observations, awaiting further verification by controlled prospective trials, underline the impact of oral health on general well-doing.

[Acid mist occupational exposure and oral disease: a review]

This study is a review of published research findings on the oral effects of occupational exposure to acid mists. A literature search was conducted on MEDLINE, LILACS, SciELO, BBO, and DEDALUS, identifying eight articles and a doctoral dissertation focusing on this association. Findings were consistent with a positive association between occupational exposure to acid mists and dental erosion, according to the literature published since 1919. Studies on the association between acid mist exposure in the workplace and periodontal disease, or oral mucous lesions, were more recent and scarce, and their findings remain controversial. Several methodological drawbacks were observed, such as small sampling size and poorly developed analysis, as exemplified by little or no attention to confounding variables. These findings support the relevance of this research area and the need for improved research design. They also highlight the importance of considering oral health as a component of workers' health in effective preventive programs.

Medications: impact on dental diagnosis and treatment planning

Today, many patients regularly take prescription and over-the-counter medications that may be a risk factor for periodontal disease and caries. The sugar in many medications presents a serious caries challenge, which, in some cases, is compounded by an acidic pH. Attitude-altering medications may inhibit compliance with oral hygiene. Many medications cause xerostomia, which can lead to root surface caries and candidiasis. In many cases, these drugs cannot be substituted and dosages cannot be reduced, so it is essential to detect adverse conditions early and begin oral hygiene treatment planning to prevent more severe dental conditions from developing. This article discusses the impact of medications on treatment planning for patients who have clinical manifestations of dental problems that are attributed to medications.

[An epidemiologic examination on the prevalence of the periodontal diseases and oral pigmentation in Yusho patients in 1998]

An epidemiologic examination was carried out to reveal the prevalence of the periodontal diseases and oral pigmentation in patients with Yusho 30 years after PCBs exposure. The results obtained were as follows. 1) 69 patients out of 71 patients with Yusho, who were measured periodontal pocket depth using Ramfjord' methods, had at least one tooth with periodontal pocket deeper than 3 mm. Similarly, 241 teeth out of a total 348 examined teeth showed periodontal pocket with more than 3 mm depth. 2) Oral pigmentation was observed in 46 out of 79 patients with Yusho. In this study, gingival pigmentation was most predominant among oral pigmentation. In addition, it is of particular interest that oral pigmentation tended to be observed at a much higher frequency in younger patients with Yusho.

Medications as a risk factor for caries and periodontal disease

Since our population is aging, patients will present to our offices with more medications than in the past. Although these medications may benefit their general health, they may adversely affect their dental health. Although most medications discussed increase the risk for caries and periodontal disease, a few may actually decrease the risk.

[An epidemiologic examination on the prevalence of the periodontal diseases and oral pigmentation in Yusho patients in 1996]

An epidemiologic examination was carried out to reveal the prevalence of the periodontal diseases and oral pigmentation in patients with Yusho 28 years after PCB exposure. The results obtained were as follows. 1) 162 teeth out of a total of 309 examined teeth had a periodontal pocket deeper than 3 mm, although 32 teeth out of 162 teeth had a periodontal pocket deeper than 4 mm. 2) Oral pigmentation was observed in 47 out of 82 patients with Yusho. It was particularly noteworthy that gingival pigmentation was observed at a much higher frequency in younger patients while pigmentation of the buccal mucosa, the lips or the palate was observed at a much higher frequency in older patients.

Medications as risk factors for periodontal disease

As the United States population ages, people will be taking more medications which may benefit their general health but not necessarily their periodontal health. The effects of medications have been grouped into six categories as follows: behavioral alteration of oral hygiene methods, alteration of plaque composition, effect on gingival tissues, effect on alveolar bone, effect on gingival crevicular fluid, and effect on salivary flow. Although most medications discussed in this paper increase the risk for periodontal disease, a few may actually decrease the risk. These include the effect of phenytoin on alveolar bone, the antibacterial effect of antibiotics, the anticollagenolytic effects of tetracyclines, and the effect of non-steroidal anti-inflammatory drugs on decreasing alveolar bone resorption.

Management of periodontal disease in older patients

As the "graying of America" is accelerating, so is the incidence and severity of periodontal diseases. The clinical management of periodontal disease in an aging population is becoming an increasingly important issue for dental professionals. This article reviews age-associated risk actors that can contribute to loss of periodontal attachment. The influence of age-related systemic conditions and medications upon clinical management is also discussed.

The pharmacokinetics of phenytoin in gingival crevicular fluid and plasma in relation to gingival overgrowth

The aim of this study was to determine whether phenytoin (PHT) could be detected in gingival crevicular fluid (GCF), and to relate its concentration to both plasma level and degree of gingival overgrowth. 23 patients medicated with phenytoin for at least 6 months were clinically examined for signs of periodontal disease and gingival overgrowth. 12 patients out of these demonstrated clinically significant overgrowth and their plaque scores and gingival inflammation were greater than for the non-overgrowth group (p < 0.001). Phenytoin concentrations were determined by high performance liquid chromatography, and was detected in GCF. There was a significant correlation between the GCF and plasma phenytoin concentrations (p < 0.05), but it was not related to the extent of gingival overgrowth. Inflammation increased the GCF volume, but was not a determinant of GCF phenytoin concentration. It is concluded that effusion of phenytoin into GCF is regulated by the plasma levels of the drug, but its concentration in GCF is not related to the incidence of gingival overgrowth.

Salivary immunoglobulins in cancer patients with chemotherapy-related oral mucosa damage

In 40 patients with neoplastic disorders treated with chemotherapy containing anthracyclines or 5-fluorouracil, objective changes of the oral mucosa were registered in 22 patients (55%). Serum IgG and IgA levels and the mean serum IgG/IgA ratio were normal. On the contrary, the mean IgG/IgA salivary ratio was 1.27 (normally below 1.0) due to an increased salivary concentration of IgG (mean 0.095 g/l), but also due to a decreased IgA concentration (mean 0.075 g/l); the IgG/IgA ratio in saliva was higher in patients with objective changes of the oral mucosa (1.53). Values of the periodontal indices were compatible with the diagnosis of a manifest periodontal disease, which tended to be more severe than in control groups. A positive correlation between the gingival index and concentration of IgG in saliva, a non-linear correlation between the gingival index and salivary IgA and a positive linear correlation between serum IgA concentration and intensity of periodontal attachment level recession, indicate local and systemic immune responses to periodontal tissue alterations and dental plaque components. The IgA related local humoral immune response is, however, operating at a lower concentration level than in healthy individuals.

Repair processes in the periodontium following dentoalveolar ankylosis: the effect of masticatory function

It has recently been shown that administration of the drug 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) perturbs the homeostasis in the periodontal ligament resulting in an osteoid-mediated ankylosis between the alveolar wall and the root surface. In the present study, the events after discontinuing HEBP administration were investigated and the effect of function on repair of the periodontal ligament was evaluated. In mice, the maxillary left molars were extracted. They then received a daily subcutaneous injection of HEBP (10 mg P/kg b.w.) for a period of 50 days, were killed 24 h, 14, 28, 56 and 112 days after the last injection and their mandibles processed for light microscopy. HEBP administration caused a significant decrease of the width of the periodontal ligament space with localized ankylosis. In the period after discontinuing HEBP treatment, the newly-formed bone did first mineralize and was then partly resorbed resulting in the disappearance of the ankylotic areas. Furthermore, root resorption was seen. Finally, the periodontal ligament regained its normal architecture and width and a new layer of cementum was formed. Functional teeth showed more root resorption than hypofunctional ones and a more rapid repair of the periodontal ligament. It is concluded that in the period after HEBP treatment the periodontal ligament regains its normal width by a repair process including extensive root resorption, that seems to accelerate this process.

Glutaraldehyde preparations and pulpotomy in primary molars

The study clinically and radiographically evaluated the long-term success rate of pulpotomy treatment in pulp-exposed primary molars. Five clinicians participated in this study and four glutaraldehyde preparations included 2% buffered, 2% unbuffered, 5% buffered, and 5% unbuffered glutaraldehyde solutions were used. There were 201 children, 108 boys and 93 girls, ranging in age from 4 to 7 years with 258 primary molars treated. After 36 months, 150 teeth with complete clinical records and radiographs were available for evaluation. The treatment of 98% of the patients was clinically successful, but when evaluated radiographically the overall success rate was 78.7%. The group treated with 5% buffered glutaraldehyde showed the highest success rate (87.5%) and group treated with the 5% unbuffered solution the lowest (74.1%), but no significant difference was found among the four groups. Canal obliteration was noted in 22 teeth successfully treated. Four of the teeth that were not successfully treated had canal obliteration before other pathoses became evident. The relative high failure rate in this long-term follow-up indicated that clinicians should be cautious before extensively using glutaraldehyde as a pulpotomy agent.