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Objective To observe the effect of proximal femoral nail anti-rotation(PFNA)combined with salmon calcitonin for the treatment of unstable intertrochanteric fractures in the elderly.Methods A total of 90 elderly patients with unstable intertrochanteric frac-tures were randomly divided into group A,group B and group C(30 cases in each group).Patients in group A received open reduction with DHS,patients in group B got closed reduction with PFNA,and patients in group C received operation as group B but combined with salmon calcitonin after the operation.The intraoperative and postoperative stuation of three groups were compared.Results The intraoperative and postoperative stuation of group B was better than those of group A,the time of weight-bearing exercise and fracture healing in group C was shorter than those of group B(t =4.42;t =5.0,P <0.05).The group B had a less complication than group A(χ2 =7.03,P <0.05).Con-clusion The PFNA has a good restoration effect with shorter operative time,less bleeding and lower complication rate.And combined with the salmon calcitonin,which can shorten the time of recovery.
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AIM:To observe the expression of TLR2 and TLR4 on mast cells (MCs) in the periapical tissues from different types of human chronic periapical diseases , and to analyze the role of TLR 2 and TLR4 on tryptase-positive MCs in the immunopathogenesis of human chronic periapical diseases .METHODS: A total of 60 donors, including healthy control group , periapical granuloma group and periapical cyst group , were enrolled in the study .The periapical tis-sue specimens were fixed in 10%buffered formalin and stained with hematoxylin and eosin for histopathology , or stained with double-immunofluorescence for identification of TLR 2-tryptase and TLR4-tryptase double-positive MCs in the periapical tissues.RESULTS:Compared with the healthy control , the densities of TLR2-tryptase and TLR4-tryptase double-positive MCs in periapical tissues were significantly increased in human chronic periapical diseases (P<0.01).The densities of TLR2-tryptase and TLR4-tryptase double-positive MCs in periapical cyst group were significantly higher than those in peria-pical granuloma group (P<0.01).CONCLUSION:TLR2 and TLR4 were expressed on the MCs in the periapical tissues of human chronic periapical diseases .TLR2-tryptase and TLR4-tryptase double-positive MCs may participate in the patho-genesis of chronic periapical diseases .
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[ ABSTRACT] AIM:To investigate the effect of hyperbaric oxygen ( HBO) on hypoxia-inducible factor-1α( HIF-1α) expression in rat experimental periodontitis with psychological stress.METHODS:Male special pathogen-free Wistar rats ( n=120) were randomly divided into 4 groups:normal control group;psychological stress stimulation group;experi-mental periodontitis group: the periodontitis model was induced by wrapping 3/0 silk ligature inoculated with Porphy-romonas gingivalis around the left maxillary second molar of the rats;periodontitis model with stress stimulation group.Psy-chological stress was removed at the 9th weeks after ligature, 6 rats from each experiment group were randomly chosen to HBO treatment.The rats were sacrificed at the 2nd, 4th, 8th and 10th weeks after ligature.Gingival index ( GI) and at-tachment loss (AL) were measured before sacrifice.The histological changes of periodontal tissues were observed under microscope with HE staining.The expression of HIF-1αwas observed by the method of immunohistochemistry.RE-SULTS:The sites of gingival attachment were normal in control group and psychological stress stimulation group.Periodon-tal pocket, and periodontal attachment loss were observed in experimental periodontitis group.The tissue damage was much serious in periodontitis model with stress stimulation group.No significant difference of GI and AL among psychological stress stimulation group and normal control group during the experiment was observed.GI and AL in periodonitis model with stress stimulating group were significantly higher than those in experimental periodontitis group at the 4th and 8th weeks (P<0.01).The levels of GI and AL were significantly lower at the 10th weeks after HBO treatmnt than those in untreated groups (P<0.05).No significant difference of HIF-1αexpression scores among psychological stress stimulation group and normal control group was found.HIF-1αexpression scores in periodonitis model with stress stimulating group was signifi-cantly higher than that in experimental periodontitis group at the 4th and 8th weeks (P<0.01).At the 10th weeks after HBO treatment the levels of HIF-1αwere significantly lower than that in untreated groups (P<0.01).CONCLUSION:Stress stimulation may aggravate periodontitis by decreasing tissue oxygenation in rats.HBO may represent a useful way in psychological stress periodontitis therapy.
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[ ABSTRACT] AIM:To investigate the role of chronic psychological stress on periodontitis and the effects of hy-perbaric oxygen ( HBO) on periodontitis with psychological stress in rats.METHODS:Male special pathogen-free Wistar rats (n=80) were randomly divided into 4 groups:(1)normal control group;(2)experimental periodontitis group:the pe-riodontitis model was induced by wrapping 3/0 silk ligature inoculated with Porphyromonas gingivalis around the left maxil-lary second molar of the rats; ( 3 ) psychological stress stimulation group; ( 4 ) periodontitis model with stress stimulation group.Psychological stress was removed at the 9th week after ligature, and 4 rats from each experimental group were ran-domly chosen for HBO treatment.The rats were sacrificed at the 2nd, 4th, 8th and 10th weeks after ligature.The levels of blood glucose, adrenocorticotropic hormone ( ACTH) , corticosterone and adrenaline were measured as the stress markers. The histological changes of periodontal tissues were observed under microscope with HE staining.RESULTS:The levels of blood glucose, ACTH, corticosterone and adrenaline in psychological stress stimulation group and periodontitis with stress group were significantly higher than those in control group and experimental periodontitis group at the 2nd and 4th weeks af-ter ligature (P<0.05).The levels of the stress markers were significantly lower than those in untreated groups in the 10th week after HBO (P<0.01).The sites of gingival attachment were normal in control group and psychological stress stimu-lation group.Periodontal pocket, and periodontal attachment loss ( AL) were observed in experimental periodontitis group. The tissue damage was much heavier in periodontitis model with stress stimulation group as the furcation of tooth was ex-posed and the tissue damage was observed on both sides of the adjacent teeth.No significant difference of AL between psy-chological stress stimulation group and normal control group during the experiment was observed.The AL in periodontal model with stress stimulating group was significantly higher than that in experimental periodontitis group at the 2nd, 4th and 8th weeks (P<0.01).The level of AL was attenuated at the 10th week after HBO (P<0.01).No difference of histologi-cal change in periodontal tissues was observed between control group and psychological stress stimulation group.Severer in-flammatory changes and alveolar bone destruction were observed in periodontitis with stress group than those in experimental periodontitis group.The levels of inflammation reduced at the 10th week after HBO.CONCLUSION:Stress stimulation is one of the inducing factors of periodontitis in rats, which aggravates periodontitis.HBO may represent a useful way in trea-ting psychological stress periodontitis.
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[ ABSTRACT] AIM:To investigate the distribution of mast cells ( MCs) and the expression of transforming growth factor-β(TGF-β) on tryptase positive MCs in different types of human periapical diseases.METHODS:Total 78 cases of specimens were involved in this study, including healthy control, periapical cyst and periapical granuloma.The tissue sam-ples were fixed in 10% formalin for at least 48 h, stained with hematoxylin and eosin for histopathological examination, stained with toluidine blue staining for identifying MCs and MCs degranulation, and stained with double immunofluores-cence for identification of tryptase-TGF-βdouble positive MCs.RESULTS:The density of tryptase-TGF-βdouble positive MCs in the periapical lesions was significantly higher than that in the healthy controls ( P<0.01) .The number of TGF-βpositive MCs in the periapical cyst was significantly higher than that in the periapical granuloma ( P<0.01 ) .Compared with toluidine blue staining, the number of MCs with double immunofluorescence staining significantly increased ( P <0.01).CONCLUSION:The TGF-βpositive MCs may play an important role in the pathogenesis of human chronic peria-pical diseases, particularly in the formation of fibrous tissue in periapical cyst.Double immunofluorescence staining is more sensitive than the traditional toluidine blue staining for identifying MCs.
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<p><b>OBJECTIVE</b>To examine the effect of aqueous extracts of Scutellaria baicalensis Georgi and Radix paeoniae Alba on periodontitis mice and compare the results of the two herbs for the treatment of the periodontitis mice.</p><p><b>METHODS</b>Sixty-four SPF 12-week-old male Kunming mice were selected and randomly divided into four groups:Control group(C); Experimental periodontitis group (P):the peridontitis models in Kunming mice were prepared by wrapping silk ligature and inoculating with putative periodontopathic bacteria; Scutellaria baicalensis Georgi treatment group (SG): periodontitis was induced by the same method described above, the mice were gavaged with Scutellaria baicalensis Georgi; Radix paeoniae Alba treatment group (RG): periodontitis was induced by the same method described above, the mice were gavaged with Radix paeoniae Alba.Four mice were sacrificed at each time point of the end of 4, 6, 8 and 10 weeks in each group. The histopathological changes of periodontal tissue were observed under microscope with HE staining. The level of serum IgG1 and IgG2a was measured by enzyme-linked immunosorbent assay (ELISA) .</p><p><b>RESULTS</b>A serious inflammatory response, alveolar progressive absorption and a large number of osteoclasts were observed in the experimental periodontitis group.However, in SG and RG, the inflammation of the periodontal tissue was decreased and tissue repair was significant. The level of serum IgG2a in SG (6 week:0.934 ± 0.006, 8 week:0.743 ± 0.009, 10 week: 0.674 ± 0.008) and RG (6 week: 1.023 ± 0.032, 8 week: 0.851 ± 0.032, 10 week:0.790 ± 0.009) was significantly decreased after the mice were gavaged with the two herbs(P < 0.01). The level of serum IgG2a in SG was significantly lower than that of RG (P < 0.01). The level of serum IgG1 in SG (6 week: 0.314 ± 0.006, 8 week: 0.344 ± 0.004, 10 week: 0.367 ± 0.006) and RG (6 week: 0.287 ± 0.005, 8 week: 0.303 ± 0.058, 10 week: 0.336 ± 0.006) were significantly increased (P < 0.01). The level of serum IgG1 in SG was significantly higher than that of RG (P < 0.01).</p><p><b>CONCLUSIONS</b>Both the aqueous extracts of Scutellaria baicalensis Georgi and Radix paeoniae Alba showed therapeutic effect on periodontitis in mice.Scutellaria baicalensis Georgi was more effective than Radix paeoniae Alba.</p>
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Animals , Male , Mice , Aconitum , Immunoglobulin G , Metabolism , Paeonia , Periodontitis , Metabolism , Plant Extracts , Pharmacology , Scutellaria baicalensis , WaterABSTRACT
AIM: To investigate the expression of stem cell factor (SCF) in tryptase -positive mast cells ( MCs) in different types of human periapical diseases for determining the role of SCF and MCs in the pathogenesis of peria-pical diseases.METHODS: A total 50 cases of specimens were involved in this study, including healthy control (n=20), periapical cyst (n=15) and periapical granuloma (n=15).The tissue material was fixed in 10%formalin for at least 48 h, stained with hematoxylin and eosin for the observation of histopathology, stained with immunohistochemistry for identifying MCs and MCs degranulation, and stained with double immunofluorescence for identification of tryptase-SCF double positive MCs.RESULTS:Compared with healthy control, significantly higher densities of both total and degranu-lated MCs in human periapical lesions were observed.The densities of both total and degranulated MCs in the periapical cyst were significantly higher than that in the periapical granuloma.The density of tryptase-SCF double positive MCs in the periapical lesions was significantly higher than that in the healthy controls.The density oftryptase-SCF double positive MCs in the periapical cyst was significantly higher than that in periapical granuloma.No significant difference in the density of MCs between immunohistochemistry staining and double immunofluorescence staining was observed.CONCLUSION:The tryptase-SCF double positive MCs play an active role in the pathogenesis of the periapical inflammatory lesions, particularly in the formation of fibrous tissue in periapical cyst.The potential role of the tryptase-SCF double positive MCs relates with the initiation, development, and persistence of the periapical inflammatory process.
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AIM:To identify and quantify the expression of IL-1βand IL-17 in mast cells ( MCs) in different types of human pericapical diseases using double immunofluorescence staining .METHODS: The specimens ( n=102 ) , including healthy control ( n=35 ) , periapical cyst ( n=35 ) and periapical granuloma ( n=32 ) , were involved in the present study .The tissue samples were fixed in 10% buffered formalin for at least 48 h and then embedded in paraffin . Serial 5-μm-thick sections were deposited onto SuperFrost/Plus microscope glasses .Routine staining of the sections using hematoxylin&eosin ( HE) was performed for morphological evaluation .The number of IL-1βand IL-17 positive MCs was identified by double immunofluorescence staining .RESULTS:Compared with the healthy controls , the inflammation score of periapical lesions was significantly increased in the periapical patients (P<0.01).The density of IL-1βand IL-17 posi-tive MCs in the periapical lesions were obviously higher than that in the healthy controls (P<0.01).However, no signifi-cant difference between periapical cyst and periapical granuloma was observed .The Pearson correlation analysis showed that there was a positive correlation between the density of IL-1βand IL-17 double positive MCs and inflammation score in dif-ferent groups of specimens (P<0.01).CONCLUSION:There is significantly increased number of MCs , along with in-creased density of IL-1βand IL-17 positive MCs in human periapical lesions .The increased density of IL-1βand IL-17 positive MCs has the similar tendency as the severity of tissue inflammation in human periapical lesions , suggesting that IL-1βand IL-17 positive MCs may play an important role in the pathogenesis of human periapical diseases .
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Objective:To quantify the tryptase and T cell immunoglobulin mucin domain-3(TIM-3)double positive mast cells in hu-man chronic periodontitis tissue using double immunofluorescence staining.Methods:25 healthy controls,28 chronic mild periodontitis and 30 chronic advanced periodontitis patients were included.The gingival specimens were stained with HE for histology,and with double immunofluorescence staining for the identification of tryptase and TIM-3 double positive mast cells in gingival tissue.Results:In chronic periodontitis tissue the degree of gingival inflammation was significantly increased,the densities(cells/mm2 )of tryptase and TIM-3 double positive mast cells were significantly increased(P<0.05),in addition,that in chronic advanced periodontitis group was significantly higher than in the chronic mild periodontitis group(P<0.05).Conclusion:Tryptase and TIM-3 double positive mast cells has the similar tendency as the severity of periodontitis inflammation in human periodontitis tissue.Tryptase and TIM-3 double positive mast cells may play an important role in human chronic periodontitis.
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AIM: The purpose of this study was to investigate the role of interleukin-4 (IL-4) in the development of periodontitis in mice by low dosage of Trichinella spiralis (T. spiralis) infection.METHODS: Twenty-seven male Kunming mice in specific pathogen free grade were randomly divided into three groups: (1) the normal control group;(2) the experimental periodontitis group, which was produced by ligature of braided silk around the first maxillary molar, and was inoculated with putative periodontopathic bacteria;(3) the periodontitis with T. spiralis infection group. The mice were sacrificed at the end of 1, 3 and 5 weeks. The probing depth (PD) was measured before the mice were euthanized. The histological change of periodontal tissues was observed under the microscope after the samples were stained with hematoxylin and eosin. Furthermore, the serum level of IL-4 was determined by ELISA. RESULTS: (1) The serum level of IL-4 in T. spiralis-infected group was significantly higher than that in experimental periodontitis group (P<0.01). (2) The PD in T. spiralis-infected group was significantly lower than that in experimental periodontitis group (P<0.01). (3) Only a mild inflammatory response was observed in T. spiralis-infected animals. CONCLUSION: T. spiralis infection upregulates IL-4 expression and attenuates periodontitis in mice.
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Objective: To investigate the effect of polarizing the immune response toward the Th2 type, using intestinal nematode (Trichinella spiralis) infection, on subsequent experimental periodontitis. Methods:Thirty six SPF KM mice were randomly divided into three groups. Periodontitis group: experimental periodontitis was induced by wrapping a 5/0 silk ligature inoculated with putative periodontopathic bacteria around the first maxillary molar. Th2-polaried group: After the mice were infected with low dosage Trichinella spiralis, the experimental periodontitis model was established at that time as above. Mice were sacrificed at the end of 1, 4, 8, 12 weeks. The histological analysis of periodontal tissues was observed by microscope after the samples were stained with hematoxylin and eosin (H&E). The concentrations of IFN--y and IL-4 in mouse serum were determined by ELISA. Results; The results showed that compared with control group Th2-polaried mice had high levels of IL-4 prior nematode infection reduced the severity of periodontitis, and subsequent infection of the periodontium with oral pathogens developed minimal lesions. Few or no osteoclasts were detected in lesions of Th2-polaried group. Conclusion;These results indicate a protective role of nematode infection in Thl cell-driven periodontal damage and prompt consideration of a novel therapeutic strategy in periodontitis based on im-munological distraction.
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AIM: To evaluate the effect of mechanical periodontal treatment combined with tetracycline on per iodontal attachment level (AL) and the avidity of serum antibody against porphyromonas gingivalis( P. gingivalis) in patients with aggressive periodontitis(AgP). METHODS: Twenty- five patients with AgP and twenty periodontally healthy controls were studied (HS). Clinical examination and recordings of AL were performed before and 3,6 and 12 months after the periodontal treatment. The avidity of IgG antibody against P. gingivalis lipopolysaccharide(LPS) was measured by diethylamine dissociation ELISA. RESULTS: A significant improvement in AL was observed following treatment ( P ＜ 0. 01 ). The avidity of serum IgG antibody against P. gingivalis increased compared with controls, and was decreased significantly after mechanical periodontal treatment combined with tetracycline (P ＜ 0. 01 ). CONCLUSION: Ourresults demonstrate that mechanical periodontal treatment combined with tetracycline provides clinically favorable results in patients with AgP.
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AIM: To study the possible role of nitric oxide (NO) in the development of periodontitis and the relationship between the NO concentration and the attachment loss. METHODS: Seventy- two Sprngue- Dawley rats were randomly assigned to two groups, the control group and periodontitis group. Experimental periodontitis in rats was produced by a ligature of braided silk. The nitric oxide concentration was indirectly ascertained by the concentration of nitrite (NO2-) and nitrate (NO3-)in the gingival tissue, which was assayed by spectrophotometry. The attachment loss (AL) was measured by the technology of the cellular graphics engineering research. The histopathologic change in periodontium was observed under a light microscope by using the histotomy. RESULTS: Compared to control group, the NO2-/NO3 - concentration in gingival tissue was significantly higher in periodontitis group at four weeks and eight weeks following ligation (P＜0.01). In periodontitis group, the NO2-/NO3 - concentration in gingival tissue was higher at eight weeks than that at four weeks following ligation (P＜0.01). At four weeks and eight weeks, the AL in experimental periodontitis in rats was significantly increased than that at one week after ligation ( P＜0.01); and the AL was also much higher at eight weeks than that at four weeks (P＜0.01). CONCLUSIONS: The NO2-/NO3- concentration in the gingival tissue in periodontitis group was significantly higher than that in control group. These results demonstrate that the NO2-/NO3- concentration is related to the severity of AL, and NO synthesis is very important to the process of inflammation and lesion in periodontium. Reducing NO production may be of great therapeutic value in the treatment of periodontitis.
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AIM: To study the inhibitory effect of aminoguanidine(AG) on periodontitis. METHODS: Experimental periodontitis was produced in rats by a ligature of braided silk, the NO concentration was assayed by spectrophototometry, the attachment loss of periodontium was measured by using technology for image and graphics engineering research and the histopathologic changes of periodontium were also examined under a light microscope. RESULTS: The NO concentration significantly decreased after AG treatment for 4 weeks, and the inflammation and the damages of periodontium was also reduced significantly. CONCLUSION: The inhibition of iNOS by AG may be a potential therapeutic strategy for the treatment of periodontitis.
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AIM: To study the relationship between prostaglandins and acute pulpitis. METHODS: Rat traumatic pulpitis model was established by pulp exposure. The kinetic pathological changes in dental pulpal tissues and changes of PGE 2?6-Keto-PGF 1? and TXB 2 concentration in dental pulp were observed. RESULTS: After pulpal trauma, the dental pulp showed inflammatory changes and the concentrations of PGE 2?6-Keto-PGF 1? and TXB 2 were increased, which peaked at 6 hour post-trauma. CONCLUSION: Prostaglandins play a significant role in the pathogenesis of pulpitis.
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AIM: To investigate the titer and avidity of serum immunoglobulin G (IgG) antibody for surface antigens of Porphyromonas gingivalis (P. gingivalis) in sera from patients with early-onset periodontitis (EOP) and evaluate the interrelationship of the antibody titer and avidity. METHODS: 15 patients with early-onset periodontitis, 16 patients with adult periodontitis(AP) and 14 periodontally healthy subjects(HS) participated in this study. Levels and avidities of IgG antibody against P.gingivalis lipopolysaccharide(LPS) were measured. Serum IgG titers against P.gingivalis antigens were measured by enzyme-linked immunosorbent assay (ELISA). IgG avidity was measured by diethylamine dissociation ELISA. RESULTS: Serum IgG antibody levels against P.gingivalis LPS in EOP and AP patients were significantly higher than that of healthy subjects (P0.05). Antibody avidities to P. gingivalis in EOP were significantly higher than that of AP patients and HS group (P0.05). CONCLUSION: These results indicate that there is no correlation between antibody levels and avidities in EOP and AP patients. IgG avidity can be considered as a valuable parameter in the diagnosis of EOP.
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AIM: To observe the effect of mineral trioxide aggregate (MTA) combined with fibronectin as pulp capping agents. METHODS: The 48 pulps of 4 cats were exposed mechanically and then capped directly with MTA, MTA combined with fibronectin, calcium hydroxide, fibronectin and starch as control. After 12 weeks observation, the experimental teeth were extracted and observed with scanning electronic microscope. RESULTS: In calcium hydroxide group and MTA group, specimens showed irregular dentin bridge structures along the pulp-MTA interface. In MTA combined with fibronectin group, continuous and complete dentin bridge structures were found along the pulp-MTA interface, the crystalline-like structures were in direct contact with the dentin wall of pulp chamber, the exposed pulp sites were closed by the dentin bridge. In fibronectin and starch group, no reparative dentin was observed. CONCLUSION: The present experiment indicated that MTA combined with fibronectin was an effective pulp-capping material and may have potential for clinical application. [
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AIM: This study was aimed to assess the effect of mineral trioxide aggregate (MTA) combined with fibronectin on reparative dentinogenesis and odontoblast differentiation, investigate the possible mechanism underlying traumatized pulp repair, which would facilitate the choosing of ideal pulp capping agents. METHODS: 192 teeth from 16 adult cats were used. Class V cavties were prepared on the facial surface. The pulps of cats were exposed mechanically and then capped directly with MTA, MTA combined with fibronectin, calcium hydroxide, fibronectin and starch as control. The pulpal tissue reactions were assessed by light microscopy at healing interval of 1 and 4 weeks.RESULTS: 1 week after pulp capping, no reparative dentin formation was observed in each group. 4 weeks after pulp capping, the dental pulps capped with MTA/fibronectin showed no or slight cellular inflammatory responses and odontoblast differentiation with tublar dentin bridge on the exposed sites. In MTA group, the dental pulps showed slight to moderate cellular inflammatory responses with osteodentin formation. In calcium hydroxide group, the pulps showed moderate to severe inflammatory responses with calcified matrix. In fibronectin and starch group, no dentin bridge formation was observed, the pulps showed severe cellular inflammatory responses.CONCLUSION: (1) MTA combined with fibronectin induced to form complete and tublar dentin bridge. In MTA group, most of the formed dentin bridge was irregular and osteodentin. (2) MTA combined with fibronectin is a bioactive pulp-capping agent and has a great worth in vital pulp therapy.
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AIM:To evaluate therapeutic effect of Zhiqi oral solution on adult periodontitis. METHODS: Supragingival scaling and root planning were carried out in 100 patients with adult periodontitis. Then the patients with periodontitis were divided into two groups randomly. 32 patients in the control group took orally Metronidazole and 68 patients in the experimental group took orally Zhiqi oral solution. The pain reaction, bleeding index, probing depth, plaque index, changes of microorganisms in periodontal pocket and side effect before and after the treatment were observed at a 30 days observation period. RESULTS:Zhiqi oral solution had a therapeutic effect on periodontitis, compared with the control group ( P
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In order to analyze the association of the periodontitis severity withchanges of the human dental pulp, one hundred caries-free and restoration-free periodontallyinvolved teeth with different periodontic destruction were studied histologically. It wasfound that there was correlation between the severity of periodontitis and changes in thehuman dental pulp. The incidence of pulpal pathosis rose as the periodontic destructionbecame severe. Pulpal inflammation was related to periodontitis, but not to the severityof periodontitis. Pulpal necrosis was mostly found in the teeth with advanced periodonti-tis.