A multicenter clinical trial of PerioGardTM in distinguishing between diseased and healthy periodontal sites

Abstract We designed and performed a multicenter clinical trial to determine the relationship between measurements of the level of the enzyme aspartate amino-transferase (AST) in gingival crevicular fluid (GCF) to other measures used to detect periodontal disease and monitor outcome of treatment, including pocket depth and gingival inflammation. 32 periodontitis patients were enrolled at the University of Washington, Seattle, 30 at the University of Florida, Gainesville, and 34 at the University of Illinois, Chicago. 10 periodontally normal control subjects were enrolled at each location. 8 diseased and 4 healthy sites were designated for study in each patient and 8 healthy sites designated in each control subject. Measures of disease included pocket depth, severity of gingival inflammation, and GCF volume. AST levels were measured using the PerioGard^TM test kit. Clinical measurements were made and GCF samples harvested and tested 2X before and 2X after therapy consisting of scaling and root planing under local anesthetic. Specific design and other issues are discussed, including selection of patients and control subjects, sample size, selection of experimental test sites, methods for assessment of diseased and therapeutic improvement, harvesting of GCF, and selection of appropriate biostatistical methods for data analysis. Demographics of the patient populations at the 3 locations are reported. As expected, therapy induced only negligible changes in the measures of disease at healthy sites in control subjects, and relatively minor improvement in healthy sites in patients. In contrast, statistically significant improvement relative to pre-treatment baseline status in all 3 measures of disease was observed for diseased sites at all 3 study locations with all p-values less than 0.0002. The magnitude of improvement was comparable to that reported previously by others. The % of PerioGard-positive sites decreased significantly between the screening baseline and both post-treatment visits for patients at all 3 locations, with p values of 0.0001 to < 0.0008.     

辅助性T细胞1和2与牙周病的关系

CD4+T细胞是具有免疫活性的T细胞,是机体重要的免疫调节细胞,根据其产生细胞因子的不同分为辅助性T细胞1和2(Th1和Th2)2种亚型,Th1和Th2可相互调节,影响免疫应答.在一个正常的免疫应答中,Th1和Th2是处于动态平衡的.牙周破坏常发生于局部环境中Th1和Th2应答的失衡.任何以Th2主导的保护性应答和以Th1主导的破坏性应答的平衡转变,都可成为牙周病始发和进展的危险因素.     

Exposure measurement in the association between periodontal disease and prematurity/low birth weight

AIM: To compare the use of different definitions for exposure measurement in cases of association between periodontal disease (PD) and prematurity and/or low birth weight (PLBW). MATERIAL AND METHODS: A database from a previous case-control study was used to compare four different definitions for periodontitis: at least one site with probing depth > or =4 mm (1); at least one site with clinical attachment loss (CAL)> or =3 mm (2); at least four teeth with one or more sites presenting probing depth > or =4 mm, with CAL> or =3 mm at the same site (3); and at least four teeth with one or more sites with probing depth > or =4 mm, with CAL> or =3 mm at the same site and presence of bleeding on probing (4). The PD frequency, diagnostic values and adjusted association measurements were calculated. RESULTS: PD frequency ranged from 33.1% to 94.7%. Odds ratio(adjusted) varied slightly according to the exposure measurement used. CONCLUSIONS: The association between PD and PLBW weight was consistent, except for exposure measurement 1, i.e. using at least one site with CAL> or =3 mm for periodontitis diagnosis, while the magnitude of this varied according to the definition established.     

Serum sCD14, polymorphism of CD14−260 and periodontal infection

Background and Aims:  CD14 is a co-receptor involved in the recognition of Gram-negative and positive bacteria. Infections are known to influence serum sCD14 levels, and CD14 gene promoter polymorphism (CD14 C−260T) has been reported to be associated with many infectious diseases. Our aim was to investigate whether serum sCD14 concentration is associated with periodontal infection and the CD14⁻²⁶⁰ genotype.
Subjects and Methods:  The periodontal status of 56 subjects with chronic periodontitis and 28 controls was clinically examined. Serum sCD14 concentration was analyzed using ELISA and CD14⁻²⁶⁰ genotype using polymerase chain reaction (PCR).
Results:  The mean concentration of sCD14 in serum was significantly higher in subjects with periodontitis than in control subjects (4.9  μ g ml⁻¹ vs 3.8  μ g ml⁻¹, P  < 0.001). Serum sCD14 concentration associated significantly with the extent of advanced periodontal disease. In a regression analysis including both subject groups, the CD14⁻²⁶⁰ genotype was a significant determinant for serum sCD14 concentration. After stratification by periodontal health status (periodontitis vs controls), the influence of the CD14⁻²⁶⁰ genotype on serum sCD14 concentration was seen only in the control group.
Conclusions:  Periodontal infection is associated with the serum concentration of sCD14. Moderate to severe periodontal infection overshadows the influence of the genotype on serum sCD14 concentration.     

Gingival fluid, beta2-microglobulin and protein levels as indicators of periodontal disease

Abstract— β₂-microglobulin (β₂-m), lysozyme and protein concentrations in gingival fluid were analyzed in 19 patients with severe periodontitis and in 19 controls devoid of any clinical signs of inflammation. A significant increase of the total protein and β₂-m levels was found in periodontal subjects. In contrast, lysozyme concentration did not reflect the inflammatory status of the periodontium. Statistical analyses showed significant correlations between β₂-m and protein concentrations in both groups. Furthermore, the values obtained by Periotron 600 closely correlated with the protein and β₂-m contents, indicating that this method is a reliable aid in assessment of the quantity and quality of crevicular exudate and thus the severity of periodontal disease.     

Cigarette smoking, salivary/gingival crevicular fluid cotinine and periodontal status. A 10-year longitudinal study

BACKGROUND, AIMS: The primary purpose of this study was to determine the association of salivary and gingival crevicular fluid (GCF) cotinine levels with periodontal disease status in smokers and non-smokers. METHODS: 147 male smokers and 30 male non-smokers were included in the current longitudinal study. The 177 individuals were part of a group of 200 subjects (89%) seen 10 years previously for a baseline survey. Oral hygiene indices, probing depth and attachment loss were recorded. Salivary and GCF cotinine levels of 58 smokers were determined by means of ELISA. RESULTS: Results indicated that no significant difference was found in subjects who smoked, when compared to subjects who did not smoke with respect to plaque accumulation and calculus deposits. Smokers, however, had fewer gingival bleeding sites. Cigarette smoking was associated with a greater increase in probing depth and attachment loss, as well as greater tooth loss at an earlier age. There was greater tooth loss in smokers than non-smokers (p < 0.001). 11 smokers became edentulous, while only 1 non-smoker lost all his teeth within 10 years. The degree of periodontal tissue breakdown was different in each age group with greater periodontal deterioration as age increased. All smokers had detectable salivary and GCF cotinine. Mean GCF cotinine was about 4x higher than mean salivary cotinine levels. Individuals who smoked > or = 20 pack years when compared to <20 pack years, had significantly higher saliva and GCF cotinine levels (p < or = 0.05). CONCLUSION: Neither salivary cotinine nor GCF cotinine was significantly correlated with probing depth, attachment loss and tooth loss (p > 0.05).     

Purification and characterization of a putative fimbrial protein/receptor of Porphyromonas gingivalis

Porphyromonas gingivalis has been implicated as a major aetiological agent in certain forms of periodontal disease. P. gingivalis is a Gram-negative, asaccharolytic bacterium that obtains energy from the fermentation of amino acids derived from the hydrolysis of host protein. Virulence factors of this bacterium include the capsule, fimbrial adhesins, cytotoxins and extracellular hydrolytic enzymes. A 43 kDa fimbrillin from P. gingivalis has been isolated and characterized. However, there is evidence that a second type of fimbria exists on the surface of P. gingivalis. A putative P. gingivalis fimbrial protein from a membrane preparation has been isolated and identified. This protein was shown to be reactive with sera from patients harbouring P. gingivalis. A 28 kDa protein fragment was purified by anion exchange, gel filtration and reversed-phase chromatography. N -terminal sequence analysis of the 28 kDa protein fragment revealed homology to the fimbrial precursor protein of Dichelobacter nodosus. A peptide corresponding to the N -terminal 26 amino acyl residues of the 28 kDa protein fragment was synthesized and used to raise antibodies to the protein. Western blot analysis after SDS-PAGE of a P. gingivalis membrane preparation using the antibodies raised to the synthetic peptide detected three proteins of 36, 41 and 67 kDa. When protease inhibitors were not included in the extraction procedure only the 36 and 41 kDa bands were detected. It would appear, therefore, that the intact protein has an M₁ of 67 kDa and that the 28, 36 and 41 kDa bands represent protein fragments produced by endogenous proteolytic activity. Based on sequence homology, the 67 kDa protein is possibly a sub-unit of a second P. gingivalis fimbrial type or a surface receptor.     

Purification and characterization of a putative fimbrial protein/receptor of Porphyromonas gingivalis

Porphyromonas gingivalis has been implicated as a major aetiological agent in certain forms of periodontal disease. P. gingivalis is a Gram-negative, asaccharolytic bacterium that obtains energy from the fermentation of amino acids derived from the hydrolysis of host protein. Virulence factors of this bacterium include the capsule, fimbrial adhesins, cytotoxins and extracellular hydrolytic enzymes. A 43 kDa fimbrillin from P. gingivalis has been isolated and characterized. However, there is evidence that a second type of fimbria exists on the surface of P. gingivalis. A putative P. gingivalis fimbrial protein from a membrane preparation has been isolated and identified. This protein was shown to be reactive with sera from patients harbouring P. gingivalis. A 28 kDa protein fragment was purified by anion exchange, gel filtration and reversed-phase chromatography. N-terminal sequence analysis of the 28 kDa protein fragment revealed homology to the fimbrial precursor protein of Dichelobacter nodosus. A peptide corresponding to the N-terminal 26 amino acyl residues of the 28 kDa protein fragment was synthesized and used to raise antibodies to the protein. Western blot analysis after SDS-PAGE of a P. gingivalis membrane preparation using the antibodies raised to the synthetic peptide detected three proteins of 36, 41 and 67 kDa. When protease inhibitors were not included in the extraction procedure only the 36 and 41 kDa bands were detected. It would appear, therefore, that the intact protein has an M_r of 67 kDa and that the 28, 36 and 41 kDa bands represent protein fragments produced by endogenous proteolytic activity. Based on sequence homology, the 67 kDa protein is possibly a sub-unit of a second P. gingivalis fimbrial type or a surface receptor.     

Phospholipase A2: a possible virulence factor of Capnocytophaga ochracea

The phospholipase A₂ (PLA₂) activity of 14 Capnocytophaga ochracea and 5 Bacteroides intermedius strains were measured with a radio assay. C. ochracea strains showed PLA₂ activity with a mean of 21.4 ± 2.2 μg liberated fatty acid. B. intermedius , a known PLA₂ producer, reached in our assay a mean of 26.8 ± 6.4. All the strains studied released free fatty acids slowly from the substrate: 4–6-day incubation was needed to reach the maximum activity. Capnocytophaga isolated from the diseased and healthy gingival pockets of patients with localized juvenile periodontitis (LJP) showed a tendency of producing more PLA₂ during the 2 first days of incubation than isolates from healthy controls or the B. intermedius strains. This tendency disappeared after day 3, and B. intermedius strains were more potent than C. ochracea on days 4–6. The activity was independent of the two bacterial culture media used in this investigation. We report PLA₂ activity as a new possible virulence factor for C. ochracea.     

Comparison of surgical and nonsurgical treatment of periodontal disease A review of current studies and additional results after 6 1/2 years

Abstract. Many well designed clinical studies have established the effectiveness of periodontal therapy. Surgical procedures have been shown to be effective in treating periodontitis when followed by appropriate maintenance care. Scaling and root planing alone have recently been compared to scaling and root planing plus soft tissue surgery in several longitudinal trials. A review of the literature indicates several important findings including a loss of clinical attachment following flap procedures for shallow (1–3 mm) pockets and no clinically significant loss after scaling and root planing. These studies also generally report either a gain or maintenance of attachment level for both procedures in deeper pockets (≥4 mm). For these pockets, neither procedure has been shown to be uniformly superior with respect to attachment gain. All reports indicate that both treatment methods result in pocket reduction. However, the literature also indicates that scaling and root planing combined with a flap procedure results in greater initial pocket reduction than does scaling and root planing alone. This difference in degree of pocket reduction between procedures tends to decrease beyond 1–2 years. It has been shown that both treatment methods result in sustained decreases in gingivitis, plaque and calculus and neither procedure appears to be superior with respect to these parameters. Additional data from the study at the University of Minnesota indicate that similar results are maintained up to 6 1/2 years following active therapy. Pocket depth did not change for shallow (1–3 mm) pockets treated by either scaling and root planing alone or scaling and root planing followed by a modified Widman flap. For pockets 4–6 mm, both treatment procedures resulted in equally effective sustained pocket reduction. Deep pockets (≥ 7 mm) were initially reduced more by the flap procedure. After 2 years, no consistent difference between treatment methods was found in degree of pocket reduction. However, as compared to baseline, pocket reduction was sustained to 6 1/2 years with the flap and only 3 years with scaling and root planing alone. After 6 1/2 years, sustained attachment loss in shallow (1–3 mm) pockets was found after the modified Widman flap. Scaling and root planing alone in these shallow pockets did not result in sustained attachment loss. For pockets initially 4–6 mm in depth, attachment level was maintained by both procedures but scaling and root planing resulted in greater gain in attachment as compared to the flap’at all time intervals. Treatment of pockets ≥ 7 mm in depth by either procedure resulted in a sustained gain in attachment with no difference between procedures. The results of these studies indicate that both scaling and root planing as well as scaling and root planing combined with a flap procedure are effective in treating periodontitis over time up to 6 1/2 years. Individual variations among patients were noted. Decisions for or against soft tissue surgery must be made on the basis of individual patient considerations.     

Changes in TGF-β1 levels in gingiva, crevicular fluid and serum associated with periodontal inflammation in humans and dogs

Transforming growth factor-beta (TGF-β) represents a family of polypeptide growth factors, involved in embryogenesis, inflammation, regulation of immune responses and wound healing. To determine whether TGF-β contributes to the evolution of periodontal disease, we assayed TGF-β levels in gingiva and crevicular fluid of patients with gingivitis and periodontitis. In parallel, TGF-β was quantified m gingival fluid and serum of beagles with experimentally-induced periodontitis. Disease was monitored by several clinical parameters including Plaque Index, Gingival Index, probing depth, and epithelial attachment loss. Gingival tissues were obtained from 9 patients at the time of periodontal surgery, and gingival fluid samples were collected from an additional population of 10 periodontal patients. In 14 beagles, experimental periodontitis was induced and gingival fluids collected 6 months later. Fluid was collected by paper strips and volume measured by Periotron. Additionally, sera was collected before and 9 months after the ligature-induced periodontitis in 7 beagles. The levels of TGF-β₁ were measured by ELISA. In the patients, a significantly higher concentration of TGF-β₁ was observed both in the gingival tissues and fluid samples obtained from the sites with deeper periodontal pockets than in the less involved sites. In beagles, TGF-β₁ levels measured in gingival fluid were elevated in moderate disease, declining in fluid samples obtained from the pockets during more advanced experimental periodontitis. Furthermore, with the progression of experimental periodontitis, a decrease in TGF-β₁ occurred in the sera of the beagle dogs. These data suggest that TGF-β₁ may play a řle in the pathogenesis and diagnosis of periodontal disease, and that its actions can be further explored in an animal model.     

Comparison of health behaviour and oral/medical conditions in non-insulin-dependent (type II) diabetics and non-diabetics

One hundred and two dentate patients with type II diabetes mellitus and 98 non-diabetic subjects were examined for oral conditions and metabolic state. Self-reported health behaviour was analysed. From factor analysis four factors emerged: general health behaviour (GHB), perceived fatigue (PF), diet control (DC) and regular diet (RD). In diabetics PF, DC and RD were significantly higher than that in non-diabetics. Patients with diabetes were more likely to control their disease through a programme of decreased kilojoule intake leading to weight management. However, they tended to tire. The mean gingivitis index was significantly higher (p<0.01) among diabetics (2.39) than among nondiabetics (1.99). The number of missing teeth was significantly higher (p<0.01) for diabetics (6.7) when compared with non-diabetics (4.3). On the other hand, aetiological factors (plaque, calculus) and the level of dental health behaviour as expressed in the HU-DBI scores were similar. Probing pocket depth did not differ statistically between groups. The increasing number of missing teeth in diabetics may primarily result from severe periodontitis with tooth mobility or deep pockets. Findings in this study suggest that the difference in the severity of periodontitis between diabetics and non-diabetics was significant although aetiological factors and the level of dental health behaviour were similar.     

Comparison of health behaviour and oral/medical conditions in non-insulin-dependent (type II) diabetics and non-diabetics

One hundred and two dentate patients with type II diabetes mellitus and 98 non-diabetic subjects were examined for oral conditions and metabolic state. Self-reported health behaviour was analysed. From factor analysis four factors emerged: general health behaviour (GHB), perceived fatigue (PF), diet control (DC) and regular diet (RD). In diabetics PF, DC and RD were significantly higher than that in non-diabetics. Patients with diabetes were more likely to control their disease through a programme of decreased kilojoule intake leading to weight management. However, they tended to tire. The mean gingivitis index was significantly higher (p<0.01) among diabetics (2.39) than among nondiabetics (1.99). The number of missing teeth was significantly higher (p<0.01) for diabetics (6.7) when compared with non-diabetics (4.3). On the other hand, aetiological factors (plaque, calculus) and the level of dental health behaviour as expressed in the HU-DBI scores were similar. Probing pocket depth did not differ statistically between groups. The increasing number of missing teeth in diabetics may primarily result from severe periodontitis with tooth mobility or deep pockets. Findings in this study suggest that the difference in the severity of periodontitis between diabetics and non-diabetics was significant although aetiological factors and the level of dental health behaviour were similar.