The effect of hyaluronan on bone and soft tissue and immune response in wound healing.

BACKGROUND: The aims of this study were to investigate the anti-inflammatory effect and the effect on bone regeneration of hyaluronan in surgical and non-surgical groups. METHODS: In each of 15 individuals, 2 teeth with defects of similar character and magnitude in the upper or lower jaw were chosen. There were at least 2 teeth between the test and the control sites. In the surgical group, a bioabsorbable membrane was used for both test and control sites, and hyaluronan was placed in the intrabony pocket of the test site. In the non-surgical group, the periodontal pockets were scaled and hyaluronan was administered 3 times with an interval of 1 week in the test pockets. Alveolar bone height and bone healing patterns were analyzed using digital intraoral radiographs. Measurements of bone height were performed in the original digital black-and-white radiographs to obtain quantitative data on bone gain or loss. Bone healing patterns were studied with color-coded radiographs, using specially designed software in a personal computer with subsequent combinations of radiographs. Gingival crevicular fluid immunoglobulin (Ig)G, C3, and prostaglandin E2 (PGE2) responses; periodontal probing depth; bleeding on probing; and the presence of plaque were studied to evaluate the anti-inflammatory effect. Data were obtained at baseline before treatment, and at 2 weeks, and 1, 3, 6, and 12 months after treatment. RESULTS: For the surgical treatments, bone height was increased in the test group treated with hyaluronan (mean value 2.2%, corresponding to an average increase of approximately 0.5 mm) and reduced in the control group (mean value -1.8%, corresponding to an average decrease of approximately - 0.4 mm) (P<0.05) after 12 months. For the non-surgical treatments, bone height was reduced by a mean value of -1.1% (corresponding to an average decrease of approximately -0.25 mm) in the test group treated with hyaluronan and -3.3% (corresponding to an average decrease of approximately -0.75 mm) in the control group after 12 months (N.S.). According to the digital color-coded radiographs, the test sites in the surgical and non-surgical groups showed apposition of bone minerals. Immune responses showed no differences during the 12 months studied for the surgical and non-surgical sites. Mean periodontal probing depths were reduced between 2.5 mm and 4.1 mm in the surgical and non-surgical groups. CONCLUSIONS: The observed difference in bone height between test and control sites in the surgical group after 12 months was less than 1 mm, which was only detectable on radiographs. No statistical difference was found on radiographs in the non-surgical group, where a decrease in bone height was found for both groups after scaling. Probing depth reduction after the surgical treatment, as well as after scaling and root planing, was as expected. Hyaluronan in contact with bone and soft tissues had no influence on the immune system in this study. Further studies are needed to determine the extent to which hyaluronan can lead to clinically significant healing of periodontal lesions.

Comparison of observer reliability in assessing alveolar bone changes from color-coded with subtraction radiographs.

OBJECTIVES: To assess intra- and interobserver agreement on marginal changes in periodontal bone from color-coded compared with subtraction radiographs. METHODS: Sequential radiographs from patients undergoing periodontal treatment were acquired using direct digital intra-oral radiography. Fifty-one pairs of color-coded and subtraction radiographs were produced and evaluated twice by six dentists for changes in marginal bone. Intra- and interobserver agreement were calculated. RESULTS: Intra-observer agreement was significantly higher for the color-coded radiographs (P < 0.05). Interobserver agreement was significantly higher for color-coded radiographs at the second (P < 0.001) but not the first (P = 0.34) evaluation. CONCLUSIONS: Color coding of radiographic differences by means of image addition may be a feasible alternative to the subtraction technique for evaluating periodontal bone changes.

Periodontal conditions and salivary immunoglobulins in individuals with Down syndrome.

Periodontal conditions and salivary levels of immunoglobulins sIgA, IgM, and IgG subclass distribution and albumin, quantified by enzyme-linked immunosorbent assay, were determined in 20 patients with Down syndrome and 19 healthy controls. Gingival inflammation was more extensive (P < 0.05) among Down syndrome subjects compared to controls as well as the occurrence of periodontal pockets (> 4 mm) (P < 0.05). The immunoglobulin levels of sIgA, IgM, the sum of IgG subclasses, and the concentration of albumin did not differ significantly between the 2 groups. However, the proportion of IgG1 expressed as percentage of the sum of total IgG was significantly higher (P < 0.01) in the Down syndrome group compared to controls. On the contrary, the proportion of IgG2, IgG3, and IgG4 subclasses in saliva did not differ between the 2 groups. The results indicate an altered distribution of IgG subclasses in saliva, with a higher proportion of IgG1 in Down syndrome individuals compared to controls.

Evidence for differential effects of sulphasalazine on systemic and mucosal immunity in rheumatoid arthritis.

OBJECTIVE: To study the effects of sulphasalazine (SASP) on the systemic and mucosal humoral immune systems in patients with rheumatoid arthritis (RA). METHODS: Serum concentrations of interleukin 6 (IL-6), class and subclass specific IgG, IgA and IgM, IgA and IgG antigliadin antibodies and rheumatoid factors (RF) of IgG, IgA (including IgA1 and IgA2 subclasses) and IgM isotypes were measured before and 16 weeks after sulphasalazine (SASP) therapy in 15 female and three male patients with RA. Amounts of immunoglobulins in saliva and jejunal fluid were measured as estimates of mucosal humoral immunity. RESULTS: Serum concentrations of IgA and IgG decreased significantly during SASP therapy and correlated with reduced concentrations of IL-6. In addition, levels of circulating IgA RF, IgA anti-gliadin antibodies and IgM RF decreased significantly after the treatment. In contrast, immunoglobulin levels in saliva and jejunal fluid were unaltered. CONCLUSION: SASP exerts powerful but selective inhibitory effects on systemic immunoglobulin production, whereas no effects on mucosal immunoglobulin production were observed. The decreased systemic B cell activity may be mediated by downregulation of the production of IL-6, a cytokine with Ig switching properties.

Oral conditions in individuals with selective immunoglobulin A deficiency and common variable immunodeficiency.

Saliva and serum samples were collected from 36 individuals with selective immunoglobulin A deficiency (IgAd) and 23 patients with common variable immunodeficiency (CVI). The oral examination included registration of the teeth, Russell's periodontal index (PI), pocket formation, and salivary flow rate in both unstimulated and stimulated saliva. No differences were found in salivary flow rate, number of teeth, or pocket depth when donors with IgAd or CVI were compared to age and sex matched controls. However, mucosal manifestations of lichenoid type were more frequent in both types of immunoglobulin deficient individuals. An increased PI was also seen in CVI patients. Increased serum IgG and salivary IgM levels were found in the IgAd population.