Notes: Periodontal jaw reflex, duration of percussion sounds, tooth mobility, and time-moment analysis of occlusal contacts by the T-scan system were recorded in seven pre-orthognathic surgery patients and six post-orthognathic surgery patients over a 2-year period. The results showed that: (i) reflex response to the pressure applied to the upper right central incisor in the lingolabial direction varied, depending on the background jaw-clenching force (BCF) of the same-sided first molar. The BCF level required to elicit excitatory reflexes was only 0 kgf, and inhibitory reflexes were clearly elicited with a BCF of 1 kgf and beyond before orthognathic surgery. After orthognathic surgery BCF levels required to elicit excitatory reflexes were 0–4 kgf, and inhibitory reflexes were elicited with a BCF of 6 kgf and above; (ii) duration of percussion sounds determined via an occlusal sound analyser decreased in both the upper right central incisor and upper right first molar while tooth mobility measured by ‘Periotest®’ increased in the upper right central incisor, but did not change in the same-sided first molar after orthognathic surgery; (iii) the time moments of occlusal contacts were symmetrical toward the midsagittal axis of the occlusal plane after orthognathic surgery. The centre of the anterioposterior occlusal contacts did not differ between pre- and post-orthognathic surgery groups.

Notes: The integrity of connective tissues surrounding dental implants may be influenced by a balance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). The purpose of this study was to provide an overall assessment of TIMP-1, MMP-1 and -8 levels as well as collagenase activities during the wound healing process after implantation and in peri-implantitis lesions. Peri-implant crevicular fluid (PICF) was sampled with sterile paper strips from 10 osseointegrated implants of 6 subjects. Ten implants from 6 patients affected with peri-implantitis were also assessed. Gingival crevicular fluid (GCF) from 11 periodontitis-affected patients and 10 healthy volunteers served as controls. TIMP-1 and MMP-1 and -8 protein levels in the PICF were measured by ELISA, and active and APMA-activatable collagenase activities were determined by functional assays using image-analysis after SDS-PAGE. The experiment showed a significant increase in the TIMP-1 level at 1 week after implantation as compared with that in GCF from healthy periodontium. Four weeks after implantation it had reached the same level as that in the GCF of healthy subjects. The data has also disclosed a higher post-implantation collagenase activity level at 1 week than at weeks 2, 4, and 12. This may be due to the increase in MMP-1 and -8. Furthermore, peri-implantitis and periodontitis were shown to be similar inflammatory lesions in respect to MMP-1 and -8 and collagenase activities, even though the TIMP-1/MMP-1+MMP-8 ratio was significantly lower in peri-implantitis than in periodontitis. In conclusion, the over-production of TIMP-1 in the wound area after implantation could, to some extent, inhibit excessive tissue destruction and degradation of the neo-matrix in wound repair due to MMPs.

Notes: Basic fibroblast growth factor (bFGF) is thought to play an important role in wound healing. However, its histological localization, both in normal and pathological conditions in the oral mucosa, has not been well documented. We have studied the immunolocalization of bFGF in normal gingiva and gingivaf epulis specimens corresponding to different organizing stages. In normal gingiva. bFGF was detected in subpopulations of macrophages. mast cells and most endothelial cells in the lamina propna. Granulation tissue in epulides was histopathologically classified into six organizing stages. In stages 1 and 2. a small number of bFGF-positive macrophages was seen at the periphery of ulcer bases. In stages 3 and 4. histologically characterized by prominent capillary proliferation, large numbers of bFGF-positive macrophages and mast celis were located within granulation tissue. A positive reaction for bFGF was also found in some endothelia! cells and in myxoedematous stroma that was rich in heparan sulfate proteoglycan. In stages 5 and 6, when fibrosis was accelerated. bFGF-positive macrophages and mast cells decreased in number and were localized only at the periphery of the fibrous tissue. These findings suggest that maximum amounts of bFGF are synthesized and released from some macrophages and mast cells into the extracellular matrix during neovascularization of granulation tissue.

Notes: Abstract: In order to examine the functional differentiation of tumor cells of adenomatoid odontogenic tumor (AOT) as ameloblasts and to determine the participation of the extracellular matrix (ECM) in the formation of its characteristic histologic architecture, tissue samples from five cases of adenomatoid odontogenic tumor were examined by immunohistochemical staining for enamel proteins and ECM molecules. Amelogenin, enamelin, laminin, heparan sulfate proteoglycan, fibronectin, collagen type IV and type V were immunolocalized within the luminal space and along the inner rim of duct-like structures. Eosinophilic hyaline droplets within the whorled or rosette masses of tumor cells showed basically the same staining pattern as the luminal contents. High columnar tumor cells that formed duct-like structures were immunopositive for amelogenin, while the staining intensity decreased with flattening of the cells, which was a result of luminal growth. The findings suggest that the constituent cells of duct-like structures are differentiated once to ameloblasts but fail to mature further due instead to increased production of ECM molecules and due to their retention in the lumina. It is possible to regard these special structures in AOT as stromal pseudocysts.

Notes: Memory T-cells and activated B-cells were identified in cryostat sections of adult periodontitis (AP) lesions and categorized in terms of frequency and distribution. Nineteen periodontitis biopsies were obtained at the time of periodontal surgery to remove residual periodontal pockets following the completion of initial preparation. Gingival tissues exhibited various degree of inflammation (Gl of 0-2) but probing depths of 〈 4 mm and 〈 5 mm loss of attachment. As a control, 5 gingivitis specimens (Gl of 1, probing depth and loss of attachment of ≤ 3 mm) were obtained from premolar and third molar sites requiring extraction for either orthodontic treatment or pericoronitis. Serial cryostat sections (6 μm in thickness) were prepared from each biopsy, on which a double staining avidin-biotin immunoperoxidase and avidin-biotin alkaline phosphatase technique was used to identify CD4+, CD45RO+ memory T-cells and activated CD19+ B-cells expressing CD23 or CD25. In periodontitis lesions the mean percentage of CD4+ cells expressing CD45RO was consistently high (65.9% in the crevicular (C) one-third (1/3), 61.2% in the middle (M) 1/3 and 62.5% in the oral (O) 1/3). This contrasts with the low mean percentage of CD4+, CD45RA+ naive T-cells (17.1% in the C 1/3, 14.8% in the M 1/3 and 12.4% in the O 1/3). In gingivitis specimens, the incidence of CD4+, CD45RO+ was 81.9% in the C 1/3, 81.1% in the M 1/3 and 89.0% in the O 1/3. This was higher than that of periodontitis biopsies. With CD4+, CD45RA+ the incidence was 10.0% in the C 1/3, 8.0% in the M 1/3, and 6.6% in the O 1/3 and the relationship to the periodontitis biopsies was reversed. However, the percentage of CD23+ and CD25+, CD19+ B-cells which were identified in 13 out of 19 samples from periodontitis varied significantly (0-100% for CD23, 0-36.2% for CD25) in spite of similar clinical status. The frequency of B-cells and activated B-cells in the gingivitis was much lower than that of periodontitis. These results indicate that both T-cells and B-cells were in active stage in periodontitis lesions. Differences of immunohistological features between gingivitis and periodontitis may be attributable to the heterogeneity of profiles of cytokine production by CD4+, CD45RO+“memory’ cells.

Notes: In the present study the hydroxyproline content in gingival exudate and serum obtained from individuals with periodontal disease was determined at three times; before, one month and six months after periodontal surgery. The gingival exudate was collected with filter paper strips according to the intracrevicular method. The hydrolysates of gingival exudate and serum were assayed colorimetrically for hydroxyproline.Although the hydroxyproline content of the exudate and of serum one month after surgery was higher than the values before surgery, the differences were not statistically significant. The values for exudate and serum at six months, however, were significantly lower than at one month; exudate 23.45 ± 13.13 μg/g vs. 39.85 ± 18.63, P 〈 0.05; serum 17.05 ± 2.22 μg/g ml vs. 19.34 ± 2.19, P 〈 0.05. These decreased values at six months postoperatively may reflect a decrease of collagen degradation in the course of gingival tissue repair.

Notes: The purpose of the present study was to evaluate the lymphoproliferative response of submandibular nodes cells to stimulation by phytohemagglutinin (PHA), concanavalin A (Con A), and lipopolysaccharide (LPS) following experimental gingivitis in dogs.In 4 dogs of the experimental group, gingival inflammation was induced by cervical ligatures on the left jaw, and the right jaw was kept clean by toothbrushing. In 2 dogs of the control group, toothbrushing was performed throughout. After the weight and lymphocyte number in the submandibular nodes were calculated, the lymphocyte response was determined by the uptake of 3H-thymidine.The weight and lymphocyte number of the ipsilateral nodes increased 2.2 and 3.7 times, respectively, as compared with the contralateral nodes. There was a higher background proliferation of unstimulated lymphocytes from ipsilateral nodes. The lymphocyte response to lower PHA concentration from ligated side lymphnodes significantly increased compared to that from contralateral nodes. It is suggested that the plaque accumulation and the intensive gingival inflammation considerably influence lymphocytes in the submandibular nodes.

Notes: The purpose of this study was to examine the effects of Actinomyces viscosus and Fusobacterium nucleatum sonicates on antibody formation in vitro and to elucidate their mechanisms on the cellular basis. Suspensions of A. viscosus and F. nucleatum were sonicated, and the supernatant was filtered and heated. After AKR mouse spleen cells were stimulated with sheep red blood cells, the antibody formation was assayed by counting the plaque-forming cells (PFC). Macrophages, T- and B-cells were harvested from the mouse peritoneal exudate and spleen. Mitogenicity of the sonicates was determined by counting the uptake of 3H-thymidine.The PFC number, when A. viscosus or F. nucleatum sonicate was added, increased significantly by 2.4–6.6 times more than the control. Two sonicates were found to activate the macrophages, resulting in an increase of PFC. F. nucleatum sonicate was effective to PFC response via activation of helper T-cells. Stimulation index of F. nucleatum sonicate on T-cells was 4.1 and that of A. viscosus sonicate on B-cells was 3.2. In conclusion, the enhanced antibody formation by A. viscosus sonicate depends on the activation of macrophages and B-cell mitogenicity, and the F. nucleatum sonicate enhances the PFC response by activation of both macrophages and helper T-cells and by T-cell proliferation.

Notes: Expression of mRNA for IL–α, IL-1β, IL-2, IL-4, IL-5, IL-6 and TNF-α in inflamed gingiva was quantitatively examined by ribonuclease protection assay and in situ hybridization. The IL-1β mRNA expression level was statistically high (P〈0.05) in periodontitis-affected tissues compared with that in gingivitis-affected tissues. The densities of macrophages (identified as CD68-positive cells) and CD45RO-positive cells infiltrating in the inflamed gingiva correlated statistically with IL-1β transcript levels (macrophages. P〈0.001: CD45RO-positive cells, P〈0.002). In situ hybridization revealed IL-1β mRNA expression in infiltrating cells, presumed to be macrophages. The IL-1α and IL-6 mRNA expression levels were much lower than the IL-1β transcript level, and mRNAs for IL-2, IL-4, IL-5 and TNF-α were negligible in these gingival tissues. The results indicate that IL-1β is a cytokine expressed predominantly in inflamed gingiva and reflects the density of infiltrating macrophages and other leukocytes.

Notes: This paper describes the presence and amounts of free glucose, hexosamine and hexuronic acid in the gingival exudate. Exudate was sampled on filterstrips from individuals with different degrees of gingival inflammation. The strips were weighed before and after absorption of exudate and the exudate was calculated. The exudate was extracted and the content of glucose, hexosamine and hexuronic acid was determined colorimetrically. In keeping with previous studies the amount of exudate increased with the severity of inflammation. Exudate glucose varied between 1.13 and 7.09 μg/mg exudate. The hexosamine content was approximately 0.6 μg/mg and the hexuronic acid concentration varied between 50 and 60 μg/mg. The possible sources of origin of the carbohydrate components are discussed.