摘要:

Standardized periodontal lesions were produced in rats by inserting silk ligatures into the gingival sulcus of the first mandibular molars for three weeks. Ligatures were removed and the tissue left to heal for 10 weeks. The newly formed dento‐epithelial junction was investigated electron‐microscopically and compared with the same structure in control animals with an intact periodontium. No differences were found between the experimental and the control animals. The existence of a sub‐lamina lucida (a substructure of the internal basement lamina) was confirmed, as described previously in mo

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00383.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The water binding capacity of porcine periodontal ligament samples was measured using the method of thermocouple psychrometry. The measured values for relative water capacity were 0.55 ± 0.07, 0.28 ± 0.05, and 0.20 ± 0.02 MPa−1, at water chemical potentials of −2, −3, and −4 MPa. The measured water capacity is consistent with reported values for tooth displacement at small forces, but not at larger forces. This implies that water binding in the ligament could account for the viscoelastic properties at low stress, but not at hig

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00384.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The ultrastructural changes occurring within the epithelium of the palate, attached gingiva, tongue, buccal mucosa, and alveolar mucosa of the vervet monkey when a mechanical load was applied to the tissues was examined. The effect of the load was assessed in terms of changes in epithelial cell and nuclear shape, intracytoplasmic structures, cell membrane interdigitation, intercellular space, and changes in the shape of non‐keratinocytes found within the epithelium. Loading produced a flattening of cells and nuclei throughout the epithelium. Intercellular space was reduced, cell membranes were flattened or else underwent increased interdigitation, tonofilaments became functionally oriented, and cytoplasmic vacuolation took place. The mitochondria appeared unchanged on loading. These changes were more marked in the nonkeratinized buccal and alveolar mucosa than in the keratinized palate, tongue, and attached gingiva. A histometric analysis which was carried out on the normal and loaded attached gingiva and alveolar mucosa revealed that the cells and nuclei of both tissue types underwent a significant change in width when loaded. Loading produced no significant change in the diameter of mitochondria in the basal and spinous layer

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00385.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

One hundred and fourteen pairs of transversally cut root sections ∼150 μm thick were obtained from porcine premolars and were attached to the floor of 35 mm culture dishes leaving an interdental space (IDS) of ∼500 μm between their cemental surfaces. Following partial demineralization of half of the samples, human gingival fibroblasts (HGF) were seeded in each dish and supplemented daily with 50μg/ml of vitamin C. The cultures were observed daily using phase microscopy. Demineralized and non‐demineralized specimens were obtained at each of 12 h, 24 h, 5, 10, 20, and 30 days, stained with van Gieson's picro‐fuchsin for identification of collagen or processed for examination by scanning electron microscopy (SEM). Two of the 30‐day‐old cultures were processed for examination by transmission electron microscopy.Sheets of oriented cells anchored to the cemental surfaces of the root sections and the floor of the dish were evident at 5 days. After 10 days of culture, a multilayered bridge‐like structure of oriented cells and fibrils (50–100 nm thick) was seen to connect the opposing cemental surfaces bordering the IDS at one or more sites. Oriented fine fibrillar structures were observed at this time using van Gieson's staining. The IDS was completely filled with oriented cells and fibers after 20 days of culture. Similar structures extending between the cemental surfaces and the floor of the dish developed around the rest of the circumference of the root sections. The appearance of this material at 30 days as observed by van Gieson's staining was reminiscent of transseptal and dento‐gingival fibersin vivo. The staining by van Gieson's method, the size of the fibrils, and the banded fibrils observed by TEM in cultures 30 days old suggest that the fibrillar material was predominantly collagen.The system was significantly more reproducible when demineralized rather than mineralized sections of root were used. It is suggested that attachment, migration, and contraction of the HGF are crucial for the orientation of the cellular and endogeneously produced fibrillar componentsin vitroand that these processes may operate in the development and healing of oriented fiber systemsin vivo. Further, partial demineralization may facilitate these proces

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00386.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

A longitudinal study on the composition of crevicular fluid (CF) and serum was carried out in seven beagle dogs during a period from health to 16 weeks of gingivitis and then 8–10 weeks of ligature induced periodontitis (LIPD). The fluids were collected at weekly intervals and the pH and the concentrations of Ca, Mg, Na, and K and the protein profile were determined. Also at weekly intervals, the plaque index, gingival index, calculus index, and pocket depth and attachment loss were recorded for the teeth from which crevicular fluid was collected. Radiographs were taken on the 0 day and after the dogs were sacrificed. Histopathological studies were carried out following sacrifice of the dogs, and the distances between the cemento‐enamel junction and the coronal end of the junctional epithelium and the cemento‐enamel junction and the crest of the alveolar bone were measured.A two‐way ANOVA analysis of the two fluids (CF and serum) and of the two diseases (gingivitis and periodontitis) showed significant differences between the two fluids and between the two diseases. Further statistical analysis showed that in serum none of the constituents studied differed significantly between gingivitis and LIPD, but a significant rise in the concentrations of Ca, Mg, and K was observed in CF during LIPD. The pH of CF was significantly lower during LIPD, but no significant change was observed in the concentration of Na ion. An apparent relationship was observed only between the concentration of K ion in CF and the attachment loss during LIPD.The serum protein profile remained unchanged throughout the period of this study. During gingivitis the CF protein profile was identical to that of serum, but during LIPD a new protein peak appeared. This material had a molecular weight of<200,000 daltons. Histopathological and radiographic analysis showed bone loss in all but one dog during LIPD. Histopathological study also showed no significant difference in the distance between CEJ and the coronal end of the junctional epithelium between the ligated and the non‐ligated sides. This study showed that in beagle dogs the CF differed significantly from that of serum. Also, LIPD caused significant changes in both ionic concentrations and protein profile of crevicu

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00387.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Diabetes increases gingival collagenase activity, an effect that may be mediated by endogenous tissue changes and exacerbated by an overgrowth of Gram‐negative organisms in the gingival crevice (see Ramamurthy&Golub 1983, McNamara et al. 1982). In an attempt to reverse this collagenolytic abnormality, we administered an appropriate antibiotic, minocycline (a semisynthetic tetracycline), to diabetic rats and humans. Adult male conventional or germfree rats were made diabetic with streptozotocin, and half of these animals were administered minocycline (20 mg per day) by tube feeding for 3–4 weeks prior to sacrifice. The buccal gingiva, entire skins, and mandibles were dissected and tested for collagenolytic enzyme activity, collagen content, and alveolar bone loss, espectively. In a preliminary study, minocycline (200 mg per day) was administered for 7 days to an insulin‐dependent diabetic adolescent human and an adult non‐diabetic human; the twin brother of the diabetic was treated with penicillin. Gingival fluid collagenase activity was measured (using [3H‐methyl] collagen as substrate in a new microassay) in 8 periodontal pockets in each subject before and after antibiotic therapy. Examination of collagenase digestion products by SDS‐polyacrylamide gel electrophoresis and fluorography was also carried out. In rats, minocycline treatment: (1) suppressed the abnormally elevated collagenolytic enzyme activity in gingiva of diabetic rats, even under germfree conditions; (2) inhibited PMN leukocyte collagenase activityin vitro, an effect that was reversed by the addition of calcium ions (penicillin‐streptomycin had no effect on the activity of this enzyme); and (3) retarded the abnormal loss of skin collagen and alveolar bone in diabetic rats. In a preliminary study on humans, minocycline therapy reduced the collagenase activity of gingival crevicular fluid, an effect not produced by penicillin.Our data suggests that (1) tetracycline therapy inhibits tissue collagenolytic enzyme activity by a mechanism al least in part unrelated to its antibacterial efficacy, and (2) this mechanism may provide a new therapeutic approach for suppressing excessive collagen resorption which occurs during periodontal disease and which can occur during other patholog

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00388.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Serum alpha‐2‐macroglobulin (α2M), IgA, IgG, and IgM concentrations in relation to the total protein as well as total and differential white blood cell counts were determined in 25 Caucasian patients, 18 females and 7 males, with juvenile periodontitis (JP). Fifteen patients, aged 15–24 years, formed the JP group and ten patients, aged 25–30 years, the post‐JP group. The α2M values were normal: means 2.91 ± 0.85 g/l in the JP group and 2.62 ± 0.56 g/l in the post‐JP group. Eight of the eleven patients in JP group and three out of ten patients in the post‐JP group showed elevated percentage lymphocyte counts, but the absolute numbers of cells were within normal range. The mean level of IgA was 2.66 ± 1.39 g/l in the JP group and 1.96 ± 1.22 g/l in the post‐JP group. The mean level of IgG was 13.08 ± 2.62 g/l in the JP group and 13.32 ± 4.88 g/l in the post‐JP group. The mean IgM was 1.86 ± 0.82 g/l in the JP and 2.30 ± 0.66 g/l in the post‐JP group. There were no statistically significant differences in the serum protein mean values between the JP and post‐JP groups. The differences between the JP or post‐JP group immunoglobulin means compared to normal means w

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00389.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The objective of this study was to determine if the level of incorporation of3H‐thymidine in unstimulated cultures of peripheral blood lymphocytes obtained from young adults differs as a function of their periodontal status. Kinetic studies using normal PBL indicated that the rate of3H‐thymidine uptake in unstimulated cultures began to increase markedly by day 5 of culture, peaked about day 7, and then declined. When this spontaneous lymphocyte proliferative response in young adults with a healthy periodontium (HP) was compared with the response obtained from young adults with severe periodontitis (SP) and individuals with juvenile periodontitis (JP), it was observed that responses in the SP group were markedly depressed at day 5 and day 7. In contrast, responses in the JP group were nearly identical to the HP controls. Periodontal treatment of the SP group appeared to restore normal responsiveness. We believe the most likely bases for these responses to be autologous mixed lymphocyte culture reactions. The suppression of the spontaneous response in the untreated SP group may reflect changes in regulatory T‐cell function induced by a state of active di

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00390.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Lipopolysacharide was isolated formCapnocytophaga sputigenastrain 4 by the butanol‐water method, and its release and association with acid (AcP) and alkaline (AIP) phosphatase was compared. Approximately 70% of the AcP and AIP was released with the butanol‐water extracted LPS (BLPS), with one‐third of the released phosp0hatases co‐eluting with it on Sepharose 4B. The BLPS was low in carbohydrate, KDO, lipid, heptose, hexosamine, and higher in phosphate and protein that the phenol‐water (PLPS) extracted LPS, SDS‐PAGE‐periodic acid Schiff staining revealed carbohydreate in both LPS preparations, while Commassie Blue staining revealed peptides only in BLPS, occurring as several minor bands and one major band at 39–41 kilodaltons. Immunoferritin reactions localized the LPS at the surface of intact C. sputigena; both LPSs were, however, immunochemically distinct. Incorporation of 3H‐thymidine into BLPS stimulated whole and T‐depleted C3H/HeJ mouse spleenocytes 7 and 4 fold, respectively higher than with PLPS. A phosphatase‐LPS interaction employing purified m

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00391.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY