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At least 253 records · Page 14Linked to original sources
PubMed2001

Restorations with extensive dentin/enamel-bonded ceramic coverage. A 5-year follow-up.

The durability of restorations with extensive dentin/enamel-bonded posterior partial and complete ceramic coverages were investigated. The effect of luting with a dual-cured and a self-cured luting agent was also studied. In 110 patients, 182 ceramic coverages (IPS Empress) were placed. In 58 restorations, Syntac was used in combination with the dual-cured resin composite Variolink. In the other restorations luted with the chemically cured resin composite Bisfil 2B, 25 were bonded with Gluma, 57 with Allbond 2, and 42 with Syntac. Of the 182 ceramics, 13 (7.1%) were assessed as non-acceptable after a mean observation period of 4.9 yr (range 4.3 7.5 yr). The reasons for failure were fracture (5), lost restorations (4), secondary caries (3) and endodontic treatment (1). No significant differences in failure rate were seen between the two luting agents or between the three dentin-bonding agents. Ceramic coverages placed on non-vital teeth failed in 9.7% of cases (3/31) and on vital teeth in 6.6% (10/151). The success rate of the dentin-enamel-bonded ceramic coverages reduces the need for a traditional full-coverage therapy and/or post or pin(s) and core placement. The technique investigated showed many clinical advantages such as less destruction of healthy tissue, and avoidance of endodontic treatment and/or deep cervical placement of restoration margins.

Adult↗
PubMed2002

Relationship between stressful situations, salivary flow rate and oral volatile sulfur-containing compounds.

The relationship between stress, salivary flow rate and oral volatile sulfur-containing compounds (VSCs) is not clearly established. Two stressful situations were studied: psychological stress caused by a biochemistry examination (Study I) and psychophysiological stress caused by premenstrual syndrome (PMS) (Study II). Seventy-one undergraduate dental students took part in Study I and VSCs were measured 1 wk before the examination, on the day of examination and 1 wk after. In Study II, 50 women were selected (23 with and 27 without PMS) and the measurements were made during non-menstrual, premenstrual and menstrual stages. Unstimulated salivary flow was determined in the subjects of both studies. On the day of the biochemistry examination, VSCs significantly increased and salivary flow decreased compared with baseline values. Women with PMS showed higher VSC concentrations during the premenstrual stage than those without PMS (P < 0.05), but the salivary flow was not statistically different. A change in VSCs was observed during different stages of the menstrual cycle for the groups of women, but the salivary flow did not change. The results suggest that a stressful situation can be a predisposing factor for the increase of VSCs in the mouth air, but the mechanism cannot be simply explained by reduction of the salivary flow.

Adolescent↗
PubMed2002

Effects of locally-delivered human macrophage products and estrogen on murine inflammatory bone resorption.

The objective of this study was to use an in vivo model of periodontitis (mouse calvaria) to quantify the effects of local release of secreted human macrophage products, 17beta-estradiol (E2), and proinflammatory lipopolysaccharide (LPS) on histologic bone resorption. Human THP-1 monocytes (106) were converted to macrophage phenotype by 500 ng/ml phorbol 12-myristate- 13-acetate (PMA) and treated as follows: no stimulation or Escherichia coli LPS (10 microg/ml) alone or in combination with a physiologic dose of E2 (100 pg/ml) for 24 h in RPMI/10% FBS, washed extensively, then incubated for 24 h in serum-free media. Supernatant products were concentrated and incorporated into a 4% (w/v) methylcellulose gel. Separate gels were incorporated with the following: LPS (500 microg/animal) alone, high dose of E2 (10 ng/animal) alone, a combination of LPS + E2, or gel only (controls). Loaded or control gels were placed into a polylactic acid occlusive dome, inserted subcutaneously over the calvaria of mature ovariectomized ICR Swiss mice (8 mice x 7 groups x 2 times [5/14 days] = 112 animals), then calvaria were evaluated histologically. Macrophage stimulation with LPS alone, but not LPS in combination with E2, produced supernatants which upregulated osteoclast numbers in the suture area compared to gel controls at 5 days (p = 0.009). The addition of LPS directly to the local delivery gels significantly upregulated osteoclasts in endosteal surfaces compared to gel controls at 5 days (p = 0.024) and at 14 days (p = 0.025). The addition of E2 to LPS down-regulated resorption to a level not different from gel controls at 14 days. This in vivo model appears effective in studying inflammatory bone resorption, which may be inhibited by E2 directly or through its influence on secreted macrophage products.

Analysis of Variance↗
PubMed2002

Parotid salivary S-IgA antibodies during experimental gingivitis in smokers and non-smokers.

Persons who smoke display a less pronounced increase of gingival bleeding in the experimental gingivitis model as compared with non-smokers. The aim of the present study was to investigate whether this could partly be explained by differences in levels of parotid total secretory IgA (S-IgA) or parotid S-IgA reactive with selected oral microorganisms. Parotid saliva samples were obtained from 11 smoking and 14 non-smoking volunteers, at baseline, after 5 and 14 days of full mouth experimental gingivitis. Output levels of total S-IgA and of specific S-IgA reactive with cell extracts from Actinobacillus actinomycetemcomitans, Actinomyces naeslundii, Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Peptostreptococcus micros, Streptococcus gordonii and Streptococcus mutans were determined in the samples by means of ELISA. Smokers and non-smokers were found to have similar output levels (microg/min) of total S-IgA, and the values did not significantly change during the experimental gingivitis trial. Parotid salivary outputs (units/min) of the bacteria-specific S-IgA at baseline and at days 5 and 14, were not different between smokers and non-smokers; no changes were observed during the experimental gingivitis trial. The present observations indicate that total S-IgA and bacteria-specific S-IgA in saliva are not main factors that can explain the less pronounced increase of gingival bleeding in the experimental gingivitis model in smokers as compared with non-smokers.

Actinomyces↗
PubMed2001

Epidermal growth factor in saliva and serum of patients with cyclosporin-induced gingival overgrowth.

The purpose of this study was to investigate the presence of epidermal growth factor (EGF) in patients receiving cyclosporin therapy who had gingival overgrowth and to determine whether there were any differences between these patients and normal healthy controls. Seventeen patients with cyclosporin-induced gingival overgrowth and seventeen age- and sex-matched controls who were taking cyclosporin but had healthy gingiva were used for this study. Unstimulated whole saliva was collected from all individuals by expectoration. Gingival crevicular fluid (GCF) was also collected from all individuals. Blood was additionally collected from all subjects and serum was separated by keeping the samples overnight at 4 degrees C. EGF levels in all cases were measured by an ELISA assay. EGF concentrations were found to be significantly higher in the saliva of patients with cyclosporin-induced gingival overgrowth compared to the control group (401.2 +/- 31.1 pg/ml and 144.3 +/- 31.4 pg/ml, respectively), whereas the results were reversed in the serum (67.0 +/- 15.6 pg/ml and 141.6 +/- 17.7 pg/ml, respectively). EGF was not detected in the samples of GCF in either group. This study thus demonstrated an increase in EGF levels in the saliva and a decrease of EGF in the serum of patients with cyclosporin-induced gingival overgrowth.

Case-Control Studies↗
PubMed2002

Salivary IgA subclasses and bacteria-reactive IgA in patients with aggressive periodontitis.

The local salivary immunoglobulin A (IgA) response in patients with aggressive periodontitis to oral microorganisms and its role for the pathogenesis has not been determined. This study investigated the hypothesis that aggressive periodontitis patients have impaired oral secretory immunity. Our test group was made-up of 19 aggressive periodontitis patients and 19 age- and gender-matched periodontally healthy controls. Total IgA, IgA subclass 1, IgA subclass 2 and IgA reactive to Actinobacillus actinomycetemcomitans Y4, Treponema denticola ATCC 35404 and Candida albicans DSM 3454 were determined by enzyme-linked immunosorbent assay in whole unstimulated and stimulated saliva. A statistically significantly lower concentration and secretion rate of total salivary IgA (P < 0.01) and IgA1 (P < 0.001) was found in the aggressive periodontitis group in resting and stimulated saliva. A decrease of IgA2 (P < 0.05) was seen in resting saliva. Although only minor differences were detected in the concentration and secretion of bacteria-reactive IgA in both groups, the proportion of bacteria-reactive IgA from the total IgA was significantly higher (P < 0.01) in the aggressive periodontitis group in all three microorganisms tested. Our results indicate an inhibition of total secretory IgA. In particular an IgA subclass 1-specific decrease in aggressive periodontitis was noted, while the bacteria-reactive humoral immune system in saliva was activated. The role of the decrease of IgA1 immunoglobulins in aggressive periodontitis with respect to susceptibility for periodontal diseases has to be elucidated.

Adult↗
PubMed2002

Hepatocyte growth factor (HGF) in periodontal disease: detection of HGF in gingival crevicular fluid.

Hepatocyte growth factor (HGF) acts as a mitogen, motogen, morphogen, anti-apoptotic factor, and scatter factor for various kinds of epithelial cells. It is a protein secreted by mesenchymal cells such as fibroblasts, and promotes motility and matrix invasion of epithelial cells. To clarify whether HGF is involved in periodontal disease, this study was conducted to determine whether HGF is present in gingival crevicular fluid (GCF) and to investigate the relationship between levels of HGF and the clinical parameters of periodontal disease, probing depth (PD), gingival index (GI) and bleeding on probing (BOP). We examined and collected GCF samples from 80 sites in 38 subjects with periodontal or other oral diseases. The concentrations of HGF, IL-1beta and PGE2 were determined by ELISA, and active collagenase activity was determined by functional assay. The HGF level correlated positively with PD and GI, and was significantly higher in specimens from BOP-positive sites and those where PD exceeded 4 mm compared with those from sites that were BOP-negative or with a PD less than 3 mm. There was a significant positive correlation between the concentrations of HGF and IL-1beta. These results indicate that the HGF level in GCF correlates well with clinical parameters of periodontal disease, and suggest that HGF may be involved in epithelial invasion through its role as a scatter factor.

Adult↗
PubMed2002

Development of oxytalan fibers in the rat molar periodontal ligament.

Although oxytalan fibers are known to be a ubiquitous component of the periodontal ligament, little information has been available concerning their organization in the developing periodontal ligament. In the present study, growth and distribution of oxytalan fibers were examined in the developing periodontal ligament of rat molars aged 11, 14, 19, 21 and 28 days. A quantitative analysis of the fibers was made and the spatial relationship between the fibers and blood vessels was studied by means of a three-dimensional reconstruction of serial sections. At the beginning of root formation, oxytalan fibers appeared at first as dot-like structures around the root sheath as well as in areas very close to blood vessels. These structures were resolved in the electron microscope to be made up of 12-nm-wide microfibrils in the vicinity of the surface of the cells of the root sheath. In the process of development, these dot-like structures elongated into entities with helical appearances. As the development further proceeded, longer oxytalan fibers were produced in the apico-occlusal direction along with blood vessels. Quantitative analysis showed that an increase in oxytalan fibers coincided with an increase in the density of the vascular network in the developing periodontal ligament. Based on the results of the present study, the role of oxytalan fibers in the developing periodontal ligament may be in the maintenance of the integrity of the vascular system as previously suggested.

Age Factors↗
PubMed2001

Healing of 208 intra-alveolar root fractures in patients aged 7-17 years.

This retrospective study consisted of 208 root-fractured, 168 splinted and 40 not splinted incisors in young individuals (aged 7-17 years) treated in the period 1959-1973 at the Pedodontic Department, Eastman Institute, Stockholm. Clinical and radiographic analyses showed that 69 teeth (33%) had developed hard tissue (fusion) healing of fragments. Interposition of periodontal ligament (PDL) and bone between the fragments was found in 17 teeth (8%). Interposition of PDL alone was found in 74 teeth (36%). Finally, non-healing with pulp necrosis and inflammatory changes between fragments was seen in 48 teeth (23%). Various clinical factors were analyzed for their relationship to the healing outcome with respect to healing/no healing and type of healing (hard tissue versus interposition of bone and/or PDL). Immature root and positive pulp sensitivity at time of injury was found to be significantly related to both pulp healing and hard tissue repair of the fracture. The same applied to concussion or subluxation of the coronal fragment compared to luxation with displacement (extrusive or lateral luxation). This relation was also represented by the variable millimeter diastasis between fragments before and after repositioning. Repositioning appeared to enhance the likelihood of both pulp healing and hard tissue repair. A positive effect of splinting, splinting methods (cap splints or orthodontic bands with an arch wire) or splinting periods could not be demonstrated on either pulp healing or type of healing (hard tissue versus interposition of bone and/or PDL). In conclusion, the findings from this retrospective study have cast doubts on the efficacy of long-term splinting and the types of splint used for root fracture healing. It is suggested that the role of splinting and splinting methods be examined in further studies.

Adolescent↗
PubMed2001

Efficacy of laser Doppler flowmetry for the diagnosis of revascularization of reimplanted immature dog teeth.

UNLABELLED: This study was performed to assess if laser Doppler flowmetry (LDF) is an improved method for the detection of revascularization of replanted teeth. Teeth were extracted and reimplanted under different experimental conditions. LDF readings were taken before extraction and weekly for 3 months. In control teeth, LDF baseline readings were taken and then repeated after the apical blood vessels were cut surgically. At the end of 3 months it was determined radiographically and histologically whether revascularization had occurred, i.e. vitality had returned. RESULTS: LDF readings correctly predicted the pulp status (vital vs. non-vital) in 83.7% of the readings. 73.9% (17 of 23) were correct for the vital teeth and 95% (19 of 20) were correct for the non-vital teeth. Fisher's exact test (2-tail) indicated that there was no significant association between the efficacy of LDF and tooth type (P = 0.166), although P2 was the least accurate tooth tested. Wilcoxon's matched-pair signed rank test demonstrated that in the revascularized (vital) teeth, the flux value between the baseline and week 2 dropped significantly (P = 0.0001), increased significantly from week 2 to week 4 (P = 0.0001) and then decreased steadily until week 12. However, at week 12 the flux was still significantly higher than at week 2 (P = 0.010). In the teeth that failed to revascularize, the flux value dropped significantly by weeks 1 and 2 (P = 0.004 and P = 0.0001, respectively). Flux values did not increase from week 2. A Fast Fourier Transform (FFT) analysis confirmed a pulse of dominant frequency of 2 Hz in the teeth that returned to vitality and the lack thereof in those that stayed non-vital. One tooth in which the flux value evaluation indicated a non-vital tooth but the radiographic/histologic findings showed vital (false negative) possessed a pulse of dominant frequency and proved by this method to have successfully revascularized.

Animals↗
PubMed2001

Comparison of a new dental trauma splint device (TTS) with three commonly used splinting techniques.

Splinting is the standard of care for stabilization of replanted or repositioned permanent teeth following trauma. The present experimental study compared four dental trauma splints in 10 volunteers. The evaluated splints included a wire-composite splint (WCS), a button-bracket splint (BS), a resin splint (RS), and a new device (TTS=Titanium Trauma Splint) specifically developed for splinting traumatized teeth. All splints were bonded to the labial surfaces of the maxillary lateral and central incisors. Splints were left in place for 1 week. After splint removal, the next splint was placed after a 1-week rest period. The sequence of splint application was randomized for each individual. The following parameters were assessed: tooth mobility with horizontal and vertical Periotest values (PTV) before and after splint application and splint removal, respectively; probing depths, plaque and bleeding on probing indices before splint application and removal, and chair time needed for splint application and removal. After splint application, horizontal PTV were significantly lower in central incisors for BS compared to TTS (P=0.04), and for RS compared to TTS (P=0.005) and to WCS (P=0.006). Reduction of lateral tooth mobility (=splint effect) expressed by the difference between horizontal pre- and postoperative PTV was significantly greater in RS compared to TTS and WCS (P<0.05) for central as well as for lateral incisors. However, changes of vertical tooth mobility were not significant across the splinting techniques. Periodontal parameters remained unchanged, reflecting the excellent oral hygiene by the study subjects. The chair time needed for splint application was significantly shorter for TTS (P<0.01). In conclusion, all tested splints appeared to maintain physiologic vertical and horizontal tooth mobility. However, the latter was critically reduced in RS splints.

Acrylic Resins↗
PubMed2002

Oral status, cognitive and functional capacity versus oral treatment need in nursing home residents: a comparison between assessments by dental and ward staff.

OBJECTIVES: The aim of this study was to study the relationships between cognitive and functional capacity versus oral health and treatment need and to compare oral status assessments and oral treatment need, assessed by nurses and dental professionals, respectively. DESIGN: Cross-sectional survey. SETTING: Nursing home. SUBJECTS: One hundred and ninety-two nursing home residents were examined in 1997. MAIN OUTCOME MEASURES: Cognitive and functional capacity in different groups of residents regarding oral health and treatment need, measured by a comprehensive assessment with the Resident Assessment Instrument (RAI) and dental status in a separate examination protocol, recorded by a dentist. RESULTS: There was a significant correlation between being dentate and having need of oral treatment. Those who were able to chew also had significantly better cognitive and functional capacity. Oral treatment need was identified most often by the dentist, intermediately by the RAI assessment and least frequently by the residents themselves. CONCLUSIONS: Being dentate and having a loss of cognitive and functional capacity is predictive of oral treatment need among nursing home residents. Enhanced interaction between nurses and dental professionals needs to be promoted for better awareness of preventive measures and better regular oral care for frail and dependent elderly persons.

Activities of Daily Living↗
PubMed2002

Nitric oxide synthesis and severity of human periodontal disease.

The expression of the inducible nitric oxide synthase enzyme (iNOS) is a response to an inflammatory stimulus and produces a large amount of nitric oxide (NO), which may act as a cytotoxic molecule against the invading microorganism and may be related to both harmful and beneficial effects to tissues. OBJECTIVE AND MATERIAL AND METHODS: In order to further characterize the presence of NO in human periodontal disease, we undertook a quantitative study of iNOS positive cells in samples of clinically healthy gingival tissues, plaque-induced gingivitis and localized chronic periodontitis using immunohistochemistry. RESULTS: A significant increase in the number of iNOS+ cells mm-2 was found in the samples of the gingivitis and periodontitis compared with those of the control. In all groups most of the polymorphonuclear cells showed intense immunoreactivity for iNOS independent of the disease stage, and the percentage of iNOS+ polymorphonuclear cells increased significantly in periodontal disease when compared with the control. CONCLUSION: Our results indicate that iNOS increases in the presence of periodontal disease. In addition, our findings suggest that polymorphonuclear cells present an additional activation pathway in periodontal disease, expressing significant iNOS and probably representing an important source of NO in human periodontal disease that has not been previously reported.

Analysis of Variance↗
PubMed2002

Salivary gland delivery of pDNA-cationic lipoplexes elicits systemic immune responses.

OBJECTIVE: To test the ability of two cationic lipoplexes, Vaxfectin and GAP-DLRIE/DOPE, to facilitate transfection and elicit immune responses from plasmid DNAs (pDNAs) after retrograde instillation into salivary glands. METHODS: Two pDNA expression vectors encoding either the influenza NP protein or human growth hormone (hGH) were complexed with the cationic lipid transfection reagents, GAP-DLRIE/DOPE or Vaxfectin, and delivered to the submandibular glands of rats. Samples from rats receiving the influenza NP protein pDNA and cationic lipoplexes were analyzed for anti-influenza NP-specific IgG1, IgG2a, and IgG2b in serum, and IgA in saliva, by an enzyme- linked immunosorbent assay (ELISA). Cytotoxic T-cell lymphocyte (CTL) assays were also performed. Transgene protein expression (hGH) was determined from extracts of submandibular glands of rats receiving hGH lipoplexes. RESULTS: Serum antibodies (IgG) against the NP protein developed and were highest in all rats vaccinated with GAP-DLRIE/DOPE or Vaxfectin. The major serum IgG subclass stimulated by this route of immunization was IgG2b, followed by IgG2a. CTL assay results showed statistically significantly higher percentage killing in the Vaxfectin group than controls (P < 0.05). No rats developed IgA antibodies to NP protein in saliva. Animals receiving plasmid encoding hGH and either lipoplex expressed significantly higher amounts of hGH compared with those receiving the hGH plasmid and water. Although hGH expression was higher in the animals receiving pDNA/Vaxfectin (approximately 30-fold > pDNA/water), the difference with those receiving pDNA/GAP-DLRIE/DOPE (approximately 10-fold > pDNA/water) was not significant. CONCLUSIONS: Retrograde instillation of pDNA complexed with Vaxfectin into the salivary glands can stimulate cytotoxic and humoral responses to the influenza NP protein antigen. Optimization of the conditions required to stimulate humoral and secretory antibody formation may facilitate use of this tissue for specific clinical applications of pDNA immunization.

Analysis of Variance↗