Theexact molecular mechanisms oftheloosening ofa dental implant arenotwell-known. Thecharacteristics of implant sulci aresimilar tothose ofperiodontal sulci regarding gingival crevicular fluid (GCF) andperi-implant sulcular fluid (PISF). Proteolytic enzymes, matrix metalloproteinases (MMPs), participate inperi-implant tissue remodeling. Clodronate isa well-tolerated bisphosphonate-group drugcurrently usedin bone-resorption-related diseases inhumans. Themechanisms ofbisphosphonate action arenotclarified. Collagenase activity indiseased PISFwassignificantly higher than intheclinically healthy group. Immunoblotting disclosed that diseased PISF contained increased immunoreactives MMP-8compared with thehealthy PISF. Theresidual latent collagenase activity inthe diseased PISFwasactivated bygold thioglucose andinhibited completely by100pM ofdoxycycline closely resembling pure neutrophil collagenase (MMP-8). Thepresence ofMMP-8in diseased butnotinclinically healthy PISFmayprove tobea useful biochemical indicator tomonitor peri-implant health and disease. Purehumanneutrophil collagenase (MMP-8) andthe MMP-8present inPISFandintheGCFofbothloosening implants andperiodontitis-af fected teeth wereefficiently inhibited invitro byclodronate (50%inhibition (IC50) was achieved by150pM ofclodronate), anosteoactive, anti- resorptive bisphosphonate. Furthermore, thenewfinding suggests anextended andhitherto-undescribed potential for clodronate inpreventing theloosening ofbothimplants and teeth, based onadualbeneficial effect: prevention ofbothbone resorption/osteolysis andofsoft tissue/dental ligament destruction. Potential newtherapeutic indications based onthe collagenase-inhibiting effect ofclodronate provide potential newtherapeutic indications for avariety ofdiseases involving connective tissue breakdown, suchasperiodontal disease, arthritides, andtumorinvasion.

Removal of miniplates is a controversial topic in oral and maxillofacial surgery. Originally, miniplates were designed to be removed on completion of bone healing. The introduction of low profile titanium miniplates has led to the routine removal of miniplates becoming comparatively rare in many parts of the world. Few studies have investigated the reasons for non-routine removal of miniplates and the factors that affect osteosynthesis after osteotomy in large numbers of patients. The aim of the present study was to investigate complications related to osteosynthesis after bilateral sagittal split osteotomy (BSSO) in a large number (n=153) of patients. In addition to the rates of removal, emphasis was placed on investigating the reasons and risk factors associated with symptomatic miniplate removal. The rate of plate removal per patient was 18.6%, the corresponding rate per plate being 18.2%. Reasons for plate removal included plate-related complications in 16 patients and subjective discomfort in 13 patients. Half of the plates were removed during the first postoperative year. Smoking was the only significant predictor for plate removal. Patients undergoing orthognathic surgery should be screened with regard to smoking and encouraged and assisted to cease smoking, at least perioperatively.

OBJECTIVE Human immunodeficiency virus (HIV)-seropositive patients have frequently severe gingival inflammation and/or attachment loss. In addition many infectious diseases affect their periodontium with varying clinical manifestations. Matrix metalloproteinases seem to play a key role in physiological periodontal remodelling and pathological tissue destruction. The aim of the present study was to characterize the presence, molecular forms, cellular sources, activities, and relative amounts of fibroblast-type (matrix metalloproteinase [MMP]-1) and neutrophil (MMP-8) collagenases, as well as their potential activator stromelysin-I (MMP-3) and myeloperoxidase in saliva of HIV-seropositive patients at different phases of HIV-infection. HIV-seronegative, healthy, age-matched patients served as controls. PATIENTS AND METHODS Saliva samples were characterized by Western blotting using antibodies specific for MMP-1, MMP-3 and MMP-8. Interstitial collagenase activities were measured using quantitative sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis/laser densitometry assay. Myeloperoxidase was analysed using quantitative dot blotting. RESULTS Clinical and microbiological evaluation of HIV-seropositive patients' periodontium showed the presence of putative periodontopathogens ie Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Peptostreptococcus micros (Psm) and Campylobacter rectus (Cr) in their periodontal pockets. The amount of Candida increased with the severity of HIV-infection. Clinical and microbiological findings of HIV-seropositive patients suggested that they have a tendency to develop periodontal disease. Interstitial collagenase activities were found to be increased in saliva of different phases of HIV-infected patients compared to the controls. Independent of the phase of HIV-infection saliva samples contained pro- and active forms of MMP-1, -3 and -8 using Western blotting. Saliva samples from healthy controls were found to contain hardly any immunoreactivities for MMP-1 or MMP-8, but considerable amounts of MMP-3 were detected. Quantitative dot blotting demonstrated increased amounts of myeloperoxidase in HIV-patients' saliva relative to controls. CONCLUSION The present results showed increased amounts of MMP-1, -3, -8 and myeloperoxidase in HIV-patients' saliva. MMP-1 and -8 may have been activated by MMP-3 and/or oxidants generated by myeloperoxidase. The increased amounts of MMPs and myeloperoxidase may reflect and directly participate in HIV-infection associated periodontitis.

The role of matrix metalloproteinases (MMPs) in response to mechanical forces in orthodontic tooth movement has only been partially clarified. In the present in vivo pilot study, the presence, levels, and degree of activation of MMP-1 and -8 were measured daily for 1 month in gingival crevicular fluid (GCF) of patients treated with orthodontic fixed appliances. GCF samples were collected from five orthodontic patients and three controls from one upper or lower central incisor or from one upper canine before fixed appliance activation and every 24 hours for 1 month thereafter. The molecular forms and activation degrees of MMP-1 and -8 in GCF were analysed by Western blotting, and MMP-8 levels determined by immunofluorometric assay (IFMA).IFMA revealed, during the study period, on average 12-fold higher levels (56 +/- 50 versus 4.6 +/- 4 microg/l) of MMP-8 in orthodontic GCF than in control GCF. The MMP-8 levels in orthodontic GCF were lower than those detected in gingivitis and periodontitis GCF, but significantly higher than in control GCF. IFMA analysis was confirmed by Western blot analysis showing elevated MMP-8 levels from orthodontic GCF relative to control GCF. Forty-one per cent of total MMP-8 immunoreactivities were high-molecular weight complexes (>100 kDa), 32 per cent in the 75 kDa pro-polymorphonuclear (PMN)-MMP-8 form, 14 per cent in the 60 kDa active-PMN-MMP-8 form, and 13 per cent in the 55 kDa fibroblast-type pro-MMP-8 form. In the GCF of orthodontic patients no MMP-1 immunoreactivities were detected. MMP-8 and -1 levels in the control GCF were low and not detectable. These results demonstrate that in vivo in human GCF, elevation and partial activation of multiple species of PMN- and fibroblast-type MMP-8 reflect periodontal remodelling during orthodontic tooth movement.

The aim of the present study was to cephalometrically compare pharyngeal changes between upright and supine positions in patients with upper airway resistance syndrome (UARS) or obstructive sleep apnoea (OSA). Eighty-two OSA patients, 70 men (mean age 49 +/- 11.8 years) and 12 women (45.9 +/- 8.3 years), underwent cephalometric sleep apnoea analysis. One upright and one supine radiograph were taken of each patient (a total of 164 cephalometric radiographs). The results showed no significant changes either in naso- or hypopharyngeal soft tissues between the two positions. In contrast, the shortest distance from the soft palate (ve1-ve2) and the tip of the soft palate (u1-u2) to the posterior oropharyngeal wall was significantly narrower (P < 0.001) in the supine position. Furthermore, in the supine position a slight thickening in the soft palate (sp1-sp2, P < 0.05) was detected with no change in the length of the soft palate (PNS-u1). The form of the tongue changed significantly: it was shorter (Tt-Tgo, P < 0.001; Tt-va, P < 0.001) and thicker (Ts/Tt-Tgo, P < 0.05) in the supine position. The present results suggest that OSA patients are prone to significant narrowing of their oropharyngeal, but not of their naso- or hypopharyngeal, airways in the supine position. Thus, treatment of OSA and UARS patients should mainly be aimed at preventing further oropharyngeal airway narrowing as a result of supine-dependent sleep.

Orthodontic force induces biochemical responses in the periodontal ligament (PDL), but the matrix metalloproteinase (MMP)-dependent molecular mechanisms in orthodontically induced periodontal remodeling have remained unclear. Previous studies indicate that mechanical stress induces MMP-1 production in human PDL cells in vitro. We tested the hypothesis whether the in vivo levels, molecular forms, and degree of activation of MMP-1 and MMP-8 in gingival crevicular fluid (GCF) reflect an early stage of orthodontic tooth movement. Molecular forms of MMP-1 and MMP-8 were analyzed by Western blot, and MMP-8 levels by quantitative immunofluoro-metric assay (IFMA). The results showed that GCF MMP-8 levels for orthodontically treated teeth were significantly higher at 4-8 hrs after force application than before activation, and when compared with the control teeth (p < 0.05). Analysis of our data indicates that the cells within the periodontium are up-regulated to produce MMP-8, and the increased expression and activation of GCF MMP-8 reflect enhanced periodontal remodeling induced by orthodontic force.

The aim of the present observational study was to identify and characterize matrix metalloproteinase (MMP) -2, -8, -9, and -13 in gingival crevicular fluid (GCF) of patients with short root anomaly (SRA). GCF samples collected from affected maxillary central incisors and premolars of five SRA patients and five systemically and periodontally healthy controls were analysed using the zymographic technique for gelatinase A and B (MMP-2 and -9) and by Western blot for collagenase -2 and -3 (MMP-8 and -13). SRA GCF revealed MMP-9 (30 per cent of the total gelatinolytic activity), of which 18 per cent was in 90 kDa proform and 12 per cent in 71-82 kDa active form. Moreover, high-molecular weight complexes (37 per cent) and low-molecular size fragmented (33 per cent) gelatinolytic enzymes were detectable. No MMP-8 or -13 immunoreactivities existed. These results may suggest that activation and complex formation of MMP-9 is characteristic of SRA GCF. From the findings it may be assumed that the GCF of SRA teeth has low collagenolytic resorptive or pathological activity.

Human immunodeficiency virus (HIV) infection has been associated with periodontal diseases in HIV-seropositive patients. In periodontal diseases, matrix metalloproteinases (MMPs) may play key roles in the extracellular matrix, basement membrane, serpin degradation, and modification of cytokine action. We characterized the 72 kDa type IV collagenase (gelatinase A, MMP-2) and 92 kDa type IV collagenase (gelatinase B, MMP-9) in the saliva of HIV-seropositive patients and seronegative healthy controls by activity measurements and quantitative immunoblotting. Immunoblot analysis with specific antibodies against MMP-2 and MMP-9 and their tissue inhibitors (TIMP-1, TIMP-2) disclosed that, independent of the phase of the patients' HIV infection, their salivary samples contained higher amounts of MMP-2 and MMP-9 immunoreactivities in pro- and active forms and the TIMP-1 and TIMP-2 inhibitors than did the control samples. Healthy control saliva contained only slight immunoreactivities for gelatinases and TIMPs. However, as judged by the studied clinical and microbiologic indicators, HIV-seropositive patients showed only a slight tendency to develop periodontitis. Overall, an increased amount of gelatinases in saliva may reflect increased host response and defense activities in HIV infection.

. Interstitial collagenase present in human jaw cyst extract and purified human fibroblast-type collagenase (MMP-1) were both efficiently inhibited in vitro by clodronate, an osteoactive, antiresorptive bisphosphonate. The IC 50 of clodronate to inhibit MMP-1 is 150 μM. These findings suggest an extended and hitherto undescribed properties for clodronate/biphosphonates in prevention and treatment of tissue degradation in both bone and soft tissue destructive diseases.

The exact molecular mechanisms of the loosening of a dental implant are not well-known. The characteristics of implant sulci are similar to those of periodontal sulci regarding gingival crevicular fluid (GCF) and peri-implant sulcular fluid (PISF). Proteolytic enzymes, matrix metalloproteinases (MMPs), participate in peri-implant tissue remodeling. Clodronate is a well-tolerated bisphosphonate-group drug currently used in bone-resorption-related diseases in humans. The mechanisms of bisphosphonate action are not clarified. Collagenase activity in diseased PISF was significantly higher than in the clinically healthy group. Immunoblotting disclosed that diseased PISF contained increased immunoreactives MMP-8 compared with the healthy PISF. The residual latent collagenase activity in the diseased PISF was activated by gold thioglucose and inhibited completely by 100 pM of doxycycline closely resembling pure neutrophil collagenase (MMP-8). The presence of MMP-8 in diseased but not in clinically healthy PISF may prove to be a useful biochemical indicator to monitor peri-implant health and disease. Pure human neutrophil collagenase (MMP-8) and the MMP-8 present in PISF and in the GCF of both loosening implants and periodontitis-affected teeth were efficiently inhibited in vitro by clodronate (50% inhibition [IC50] was achieved by 150 uM of clodronate), an osteoactive, antiresorptive bisphosphonate. Furthermore, the new finding suggests an extended and hitherto-undescribed potential for clodronate in preventing the loosening of both implants and teeth, based on a dual beneficial effect: prevention of both bone resorption/osteolysis and of soft tissue/dental ligament destruction. Potential new therapeutic indications based on the collagenase-inhibiting effect of clodronate provide potential new therapeutic indications for a variety of diseases involving connective tissue breakdown, such as periodontal disease, arthritides, and tumor invasion.

OBJECTIVE:Human immunodeficiency virus (HIV)-seropositive patients have frequently severe gingival inflammation and/or attachment loss. In addition many infectious diseases affect their periodontium with varying clinical manifestations. Matrix metalloproteinases seem to play a key role in physiological periodontal remodelling and pathological tissue destruction. The aim of the present study was to characterize the presence, molecular forms, cellular sources, activities, and relative amounts of fibroblast-type (matrix metalloproteinase [MMP]-1) and neutrophil (MMP-8) collagenases, as well as their potential activator stromelysin-I (MMP-3) and myeloperoxidase in saliva of HIV-seropositive patients at different phases of HIV-infection. HIV-seronegative, healthy, age-matched patients served as controls.PATIENTS AND METHODS:Saliva samples were characterized by Western blotting using antibodies specific for MMP-1, MMP-3 and MMP-8. Interstitial collagenase activities were measured using quantitative sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis/laser densitometry assay. Myeloperoxidase was analysed using quantitative dot blotting.RESULTS:Clinical and microbiological evaluation of HIV-seropositive patients' periodontium showed the presence of putative periodontopathogens ie Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Peptostreptococcus micros (Psm) and Campylobacter rectus (Cr) in their periodontal pockets. The amount of Candida increased with the severity of HIV-infection. Clinical and microbiological findings of HIV-seropositive patients suggested that they have a tendency to develop periodontal disease. Interstitial collagenase activities were found to be increased in saliva of different phases of HIV-infected patients compared to the controls. Independent of the phase of HIV-infection saliva samples contained pro- and active forms of MMP-1, -3 and -8 using Western blotting. Saliva samples from healthy controls were found to contain hardly any immunoreactivities for MMP-1 or MMP-8, but considerable amounts of MMP-3 were detected. Quantitative dot blotting demonstrated increased amounts of myeloperoxidase in HIV-patients' saliva relative to controls.CONCLUSION:The present results showed increased amounts of MMP-1, -3, -8 and myeloperoxidase in HIV-patients' saliva. MMP-1 and -8 may have been activated by MMP-3 and/or oxidants generated by myeloperoxidase. The increased amounts of MMPs and myeloperoxidase may reflect and directly participate in HIV-infection associated periodontitis.

Insearch ofdirect invivoevidence ofmatrix metalloproteinases (MMPs)in periodontal tissue destruction, westudied thepresence andlocalization of MMP-9andneutrophil gelatinase-associated lipocalin (NGAL)inadult periodontitis (AP)andlocalized juvenile periodontitis (LJP) gingival tissuespecimensby immunohistochemistry, andtheactivities ofgelatinases by Western blot, enzymography, andactivity measurements, using radioactive gelatin assubstrate ingingival crevicular fluid (GCF) andsaliva. Ingingival tissue obtained fromAP andLJPpatients, polymorphonuclear leukocyte (PMN)92- kDaMMP-9andNGAL wereseenintheconnective tissue, butboththesulcular andtheoralepithelia were consistently negative. WhereasPMNs located inthe gingival blood vessels showedstrictly cytoplasmic MMP-9 andNGAL immunoreactivities, inthecaseofPMN extravasation the stainingreactionsextended extracellularly. Gelatinase activities consisting mainly of92- kDagelatinase wereincreased inAP GCFrelative toLJP GCFandperiodontally healthy control GCF.Western blot withspecific anti-NGAL antibodies revealed thepresence of 25-kDaNGAL anditshigh-molecular-weight formsinAP andLJPGCFandsaliva andinculture mediumoforal keratinocytes, butnotingingival fibroblast culture medium. We conclude that extravasated degranulating PMNsarethe major source ofMMP-9andNGALinperiodontitis gingiva, GCF,andsaliva.

Matrix metalloproteinases (MMPs) and serine proteinases seem to be related to tissue destruction in periodontitis. The presence of MMPs in gingival crevicular fluid (GCF) and saliva, however, has not been studied comprehensively with the enzyme-linked immunosorbent assay (ELISA)-technique. We therefore examined the levels of MMP-1, -3, -8 and -9, and their endogenous inhibitor, tissue inhibitor of matrix metalloproteinases (TIMP-1), in GCF and saliva of patients with adult periodontitis (AP) and localized juvenile periodontitis (LJP). Elevated levels of MMP-1 were detected in LJP GCF compared to AP and control GCF. Elevated levels of TIMP-1 were also detected in LJP GCF in comparison to AP and control GCF. Higher MMP-8 levels were detected in AP GCF compared to LJP and control GCF. The relative low levels of MMP-3 were present in all studied GCF samples. Elevated levels of MMP-8 were further detected in saliva of AP compared to LJP and the controls. Both MMP-1 and TIMP-1 were detected in all studied saliva samples, but not significant differences were detected between the studied groups. Our ELISA-results confirm that (i) PMN MMP-8 and MMP-9 are the main collagenase and gelatinase in AP GCF, whereas GCF collagenase in LJP seems to be of the MMP-1-type; (ii) only low levels of TIMP-1, endogenous MMP-inhibitor, are present in AP GCF, which emphasises the importance of doxycycline as a possible adjunctive drug in the treatment of AP patients; (iii) tests based on specific antibodies against PMN MMPs, especially MMP-8, might serve as a reliable method of measuring and monitoring enzyme levels in GCF from different periodontitis patients.

In search of direct in vivo evidence of matrix metalloproteinases (MMPs) in periodontal tissue destruction, we studied the presence and localization of MMP-9 and neutrophil gelatinase-associated lipocalin (NGAL) in adult periodontitis (AP) and localized juvenile periodontitis (LJP) gingival tissue specimens by immunohistochemistry, and the activities of gelatinases by Western blot, enzymography, and activity measurements, using radioactive gelatin as substrate in gingival crevicular fluid (GCF) and saliva. In gingival tissue obtained from AP and LJP patients, polymorphonuclear leukocyte (PMN) 92-kDa MMP-9 and NGAL were seen in the connective tissue, but both the sulcular and the oral epithelia were consistently negative. Whereas PMNs located in the gingival blood vessels showed strictly cytoplasmic MMP-9 and NGAL immunoreactivities, in the case of PMN extravasation the staining reactions extended extracellularly. Gelatinase activities consisting mainly of 92-kDa gelatinase were increased in AP GCF relative to LJP GCF and periodontally healthy control GCF. Western blot with specific anti-NGAL antibodies revealed the presence of 25-kDa NGAL and its high-molecular-weight forms in AP and LJP GCF and saliva and in culture medium of oral keratinocytes, but not in gingival fibroblast culture medium. We conclude that extravasated degranulating PMNs are the major source of MMP-9 and NGAL in periodontitis gingiva, GCF, and saliva.

Previous studies have shown increased susceptibility to periodontal diseases in children with Down's syndrome (DS). The mechanisms involved in the periodontal inflammatory processes in DS are not fully understood. The present study characterized the periodontal status of 9 non-institutionalized DS children 9 to 17 years old (mean 13.6 years) relative to their age-matched systemically and periodontally healthy controls. The periodontal status was assessed by visible plaque index (VPI), gingival bleeding index (GBI), and probing depth. We also assessed, by sodium dodecyl sulphate polyacrylamide gel electrophoresis/laser densitometry and by zymography, the collagenase and gelatinase activities in the gingival crevicular fluid (GCF) and saliva samples collected from DS patients and from the controls. Eight of the nine DS children showed a periodontium comparable to that seen in healthy controls; beginning alveolar bone loss was radiographically seen in the DS patient with deep periodontal pockets. The endogenously active collagenase and total collagenase activities were slightly higher in GCF of DS children compared to healthy controls. Western blot demonstrated that GCF collagenase of DS patients was human neutrophil collagenase (MMP-8 or collagenase-2), which occurred in 75 kDa proMMP-8 and in DS patients, but not in controls, also in 65 kDa active MMP-8 form and occasionally lower 40-50 kDa MMP-8 species. Zymographic analysis revealed the presence of 120 kDa (MMP-9 complexed with neutrophil gelatinase associated lipocalin or NGAL), 92 kDa (MMP-9) and 72 kDa (MMP-2) gelatinases in DS and control GCF. Especially in DS GCF MMP-9 occurred in part in 82-85 kDa activated form. Salivary collagenase in DS was high when compared to controls but of the same MMP-8 type as in control saliva. Our findings suggest that in vivo activated MMP-8 in GCF derived from triggered PMNs and/or cytokine-induced periodontal fibroblasts may reflect periodontal tissue and alveolar bone destruction seen in the early stages of gingivitis/periodontitis associated with Down's syndrome.

The aim of the present review was to study the efficacy of scaling and root planing (SRP) with and without adjunct antibacterial photodynamic therapy (aPDT) on the expression of cytokines in the gingival crevicular fluid (GCF) of patients with periodontitis.In order to address the focused question: “What is the efficacy of SRP with and without aPDT on the expression of cytokines in the GCF of patients with periodontitis” an electronic search without time or language restrictions was conducted up to and including July 2016 in indexed databases using various key words. The exclusion criteria included reviews, laboratory and experimental studies, case reports, commentaries, letters to the editor, interviews, updates, studies where intervention group received aPDT without previous SRP, and studies where local delivery of antibiotics was used as adjunctive therapy to aPDT.Six randomized control trials were included in the present systematic review. All studies included a control group which received only SRP. Results from 34% of studies reported lower cytokine levels among individuals receiving adjunct aPDT to SPT compared to patients receiving SRP alone. Selective cytokines reduction in the GCF following SRP with adjunct aPDT compared with SRP alone was reported in 50% of the studies. In one study SRP with adjunct aPDT failed to reduce GCF cytokine concentration.From the literature reviewed the efficacy aPDT as adjunct to SRP in downregulating GCF cytokines remains debatable. Further well-designed studies are needed in this regard.

The presence, localization and activities of cathepsin G in gingival tissue specimens and crevicular fluid (GCF) from 9 adult periodontitis patients and 6 controls with clinically healthy periodontium were studied by use of avidinbiotin-peroxidase complex method, Western and dot blotting, and spectrophotometric activity assay. In contrast to healthy gingival tissue specimens, gingival tissue specimens collected from adult periodontitis patients contained inflammatory cells in lamina propria, beneath the oral sulcular epithelium, 10-50% of which were cathepsin G positive polymorphonuclear neutrophilic leukocytes (PMNs) and monocyte/macrophage-like cells. Cathepsin G activities were increased in adult periodontitis GCF when compared to periodontally healthy controls' GCF (p < 0.05). In adult periodontitis GCF, Western blotting disclosed free cathepsin G but also clear complexes of cathepsin G with its predominant endogenous inhibitor alpha 1-antichymotrypsin (alpha 1-ACT). The present results demonstrate that part of the cathepsin G, despite the presence of increased concentrations of alpha 1-ACT, was in an uncomplexed, free and functionally active form. Our results suggest that GCF cathepsin G reflects the disease process in adjacent inflamed gingiva and also increased host response to microbiota and/or dental plaque in the periodontitis lesions. Cathepsin G may contribute to periodontal tissue destruction directly and indirectly, via proteolytic activation of latent neutrophil procollagenase (promatrix metalloproteinase-8 [proMMP-8]).