bluuebunny/crossref_metadata_2025 huggingface dataset:
IL‐1 gene polymorphism and smoking as risk factors for peri‐implant bone loss in a well‐maintained population
Authors: Feloutzis Andreas , Lang Niklaus P. , Tonetti Maurizio S. , Bürgin Walter , Brägger Urs , Buser Daniel , Duff Gordon W. , Kornman Kenneth S.
Published: March 2003

Abstract: The aim of the present study was (i) to investigate the relation between specific interleukin‐1 (IL‐1) gene polymorphisms and peri‐implant bone loss at osseointegrated ITI® dental implants and (ii) to explore the association between these allelic variants of the IL‐1 gene complex and peri‐implant mucosal inflammation, in both smoking and non‐smoking individuals. A sample of 90 consecutive Caucasian patients (aged 33–88 years), treated with at least one ITI‐implant participated in this retrospective investigation. Standardized periapical radiographs were taken after prosthetic rehabilitation (133.6 days, SD 136.9 days) and at the time of the re‐examination, on average 5.6 years (SD 2.5 years) thereafter. The radiographs were analyzed by a calibrated examiner for changes in peri‐implant bone levels. The examiner was blind with respect to clinical parameters and IL‐1 status. The distance between the implant shoulder and the first visible bone‐implant contact (DIB) at the respective time points were measured using a computerized method. The absolute bone level difference during the years of service (ABL) and the annual bone loss (ΔBL/year) were calculated for all the implants. Percentages of full mouth bleeding on probing (BOP), as well as of BOP calculated separately for teeth and implants, were determined for all visits and averaged for the entire observation period. Out of the total patient sample, there were 14 heavy smokers (= 20 cigarettes/day), 14 moderate smokers (5–19 cigarettes/day), 23 previous smokers (smoking cessation > 5 years) and 39 non‐smokers. Twenty‐eight (31.11%) patients were IL‐1 genotype positive. Upon stratification for smoking status, significant differences were found for the variables ABL (P < 0.04, U‐test) and ΔBL/year (P < 0.04, U‐test) between non‐smokers and heavy smokers for the IL‐1 genotype positive group but not for the IL‐1 genotype negative group. Moreover, significant differences in ABL (P < 0.04, U‐test) and ΔBL/year (P < 0.04, U‐test) were identified between former smokers and heavy smokers for the IL‐1 genotype positive group. The differences in inflammatory parameters (BOP) did not reach statistical significance.

This study suggests that in heavy cigarette smokers, carriage of a functionally significant IL‐1 gene complex polymorphism is associated with an increased risk for peri‐implant bone loss following prosthetic reconstruction and during the supportive periodontal care phase of the treatment.
Detection of tissue plasminogen activator (t‐PA) and plasminogen activator inhibitor 2(PAI‐2) in gingival crevicular fluid from healthy, gingivitis and periodontitis patients
Authors: Yin Xiao , Bunn Clive L. , Bartold P. Mark
Published: March 2003

Background: The regulation of plasminogen activation is a key element in controlling proteolytic events in the extracellular matrix. Our previous studies had demonstrated that in inflamed gingival tissues, tissue‐type plasminogen activator (t‐PA) is significantly increased in the extracellular matrix of the connective tissue and that interleukin 1β (IL‐1β) can up regulate the level of t‐PA and plasminogen activator inhibitor‐2 (PAI‐2) synthesis by human gingival fibroblasts.

Method: In the present study, the levels of t‐PA and PAI‐2 in gingival crevicular fluid (GCF) were measured from healthy, gingivitis and periodontitis sites and compared before and after periodontal treatment. Crevicular fluid from106 periodontal sites in 33 patients were collected. 24 sites from 11 periodontitis patients received periodontal treatment after the first sample collection and post‐treatment samples were collected 14 days after treatment. All samples were analyzed by enzyme‐linked immunosorbent assay (ELISA) for t‐PA and PAI‐2.

Results: The results showed that significantly high levels of t‐PA and PAI‐2 in GCF were found in the gingivitis and periodontitis sites. Periodontal treatment led to significant decreases of PAI‐2, but not t‐PA, after 14 days. A significant positive linear correlation was found between t‐PA and PAI‐2 in GCF (r=0.80, p<0.01). In the healthy group, different sites from within the same subject showed little variation of t‐PA and PAI‐2 in GCF. However, the gingivitis and periodontitis sites showed large variation. These results suggest a good correlation between t‐PA and PAI‐2 with the severity of periodontal conditions.

Conclusion: This study indicates that t‐PA and PAI‐2 may play a significant rôle in the periodontal tissue destruction and tissue remodeling and that t‐PA and PAI‐2 in GCF may be used as clinical markers to evaluate the periodontal diseases and assess treatment.
Smoking and GCF levels of IL‐1β and IL‐1ra in periodontal disease
Authors: Boström Lennart , Linder Lars E. , Bergström Jan
Published: March 2003

Aims: GCF levels of the cytokine IL‐1β and its receptor antagonist IL‐1ra were analyzed with respect to smoking in patients with moderate to severe periodontal disease. The study population included 22 smokers and 18 non‐smokers in the age range 32–86 years. Concomitantly, the GCF levels of IgA, IgG, albumin and total protein were analyzed.

Method: Samples of GCF were obtained from 2 diseased sites in each patient by means of an aspiration method. IL‐1β, IL‐1ra, IgA and IgG were determined with immunoelectrophoresis. Total protein was determined by the BCA method.

Results: The clinical characteristics in terms of probing depth and frequency of diseased sites and supragingival plaque did not differ between smokers and non‐smokers. Gingival bleeding, however, was significantly depressed in smokers. IL‐1β was detected in GCF of 95% of both smokers and non‐smokers and IL‐1ra in all patients. The GCF level of IL‐1ra was approximately 1000‐fold that of IL‐1β. The GCF levels of IL‐1β and IL‐1ra were high in comparison with those of TNF‐α and IL‐6 determined by the same method in our earlier studies.

Conclusion: Our observations did not reveal any influence of smoking on the levels of IL‐1β and IL‐1ra in GCF.
The periodontal abscess: a review
Authors: Herrera David , Roldán Silvia , Sanz Mariano
Published: March 2003

Background/aims: The periodontal abscess is a frequent periodontal condition in which periodontal tissues may be rapidly destroyed. Its importance is based on the possible need of urgent care, the affectation of tooth prognosis, and the possibility of infection spreading. There is scant information in the scientific literature regarding this condition and most of it has been published as case reports and text books, where conclusions are not evidence‐based, but rather empirical observations made by recognised clinicians. The aim of this review was to critically analyse all available information on this subject in the dental and medical literature, including information on its prevalence, proposed etiologies and pathogenesis, diagnosis, microbiology and treatment alternatives.

The periodontal abscess is the 3rd most frequent dental emergency, and it is specially prevalent among untreated periodontal patients and periodontal patients during maintenance. Different etiologies have been proposed, and 2 main groups can be distinguished, depending on its relation with periodontal pockets. In the case of a periodontitis‐related abscess, the condition may appear as an exacerbation of a non‐treated periodontitis or during the course of periodontal therapy. In non‐periodontitis related abscesses, impactation of foreign objects, and radicular abnormalities are the 2 main causes. The abscess microflora seems to be similar to that of adult periodontitis, and it is dominated by gram‐negative anaerobic rods, including well‐known periodontal pathogens. Complications and consequences include tooth loss and the spread of the infection to other body sites. Diagnosis and treatment is mainly based on empiricism, since evidence‐based data are not available. The rôle of systemic antibiotics, in the treatment of periodontal abscesses, is especially controversial.
Treatment of intrabony defects with guided tissue regeneration and enamel‐matrix‐proteins
Authors: Sculean A. , Donos N. , Brecx M. , Reich E. , Karring T.
Published: March 2003

Background: Enamel matrix proteins (EMD) have recently been introduced in regenerative periodontal treatment. However, no histological data are yet available concerning the effect of treating intrabony periodontal defects with EMD, and no histological comparisons have been made comparing the result of treatment of intrabony defects with EMD with that of the treatment with guided tissue regeneration (GTR).

Aim: Therefore, the aim of the present study was to evaluate histologically in monkeys the effect of treating intrabony defects with EMD, GTR or combined EMD and GTR.

Method: Intrabony periodontal defects were produced surgically at the distal aspect of teeth 14, 11, 21, 24, 34, 31, 41 and 44 in 3 monkeys (Macaca fascicularis). In order to prevent spontaneous healing and to enhance plaque accumulation metal strips were placed into the defects. After 6 weeks the defects were exposed using a full‐thickness flap procedure. The granulation tissue was removed and the root surfaces were debrided by means of hand instruments. Subsequently, the defects were treated using one of the following therapies: (i) GTR, (ii) EMD, or (iii) combination of EMD and GTR. The control defects were treated with coronally repositioned flaps. After 5 months, the animals were sacrificed and perfused with 10% buffered formalin for fixation. Specimens containing the defects and surrounding tissues were dissected free, decalcified in EDTA and embedded in paraffin. 8 μm thick histological sections were cut and stained and subsequently examined under the light microscope.

Results: In the control specimens, the healing was characterized by a long junctional epithelium and limited periodontal regeneration (i.e., new periodontal ligament, new cementum with inserting connective tissue fibers and new bone) in the bottom of the defect. The GTR‐treated defects consistently presented periodontal regeneration when the membranes were not exposed whereas the sites treated only with EMD presented regeneration to a varying extent. The combined therapy did not seem to improve the results.

Conclusion: It can be concluded that all 3 treatment modalities favor periodontal regeneration.
Fcα receptor I (CD89) on neutrophils in periodontal lesions
Authors: Yuan Zuan‐Ning , Gjermo Per , Helgeland Kristen , Schenck Karl
Published: March 2003

Aims: In this study, we have examined the occurence of FcαRI‐bearing cells in gingival tissue, gingival fluid and blood, in search for possible roles of IgA and FcαRI in periodontal lesions.

Methods: Gingival biopsies from inflamed and healthy sites were obtained from patients with chronic marginal periodontitis. Sections of inflamed gingiva were examined by immunofluorescence techniques and compared to sections from healthy sites. Smears were made from blood and gingival crevicular fluid and similarly studied.

Results: Dense infiltrates of neutrophils with strong expression of FcαRI (and FcγRIII) were found in connective tissue and epithelium of the apical part of periodontal pockets from diseased sites. In contrast, only few such cells were found in healthy gingiva from the same patients. Neutrophils in gingival fluid, tissue and blood expressed FcαRI with similar intensity, whereas the expression of FcγRIII was significantly decreased in gingival crevicular fluid. Considerable numbers of bacteria from gingival plaque were found to be covered by IgA.

Conclusion: It is suggested that FcαRI on neutrophils may play an important rôle in elimination of IgA‐opsonized bacteria, both in periodontal tissue and the adjacent pockets.
Reduced numbers of Langerhans cells and increased HLA‐DR expression in keratinocytes in the oral gingival epithelium of HIV‐infected patients with periodontitis
Authors: Myint M. , Yuan Z. N. , Schenck K.
Published: March 2003

Background: HIV‐seropositive (HIV+) patients become increasingly susceptible to periodontal diseases as HIV infection proceeds. We have previously shown that HIV+ patients with chronic marginal periodontitis (CMP) have remarkably increased numbers of gingival plasma cells in the connective tissue underlying the oral gingival epithelium, but depressed specific serum IgG levels towards periodontopathogenic bacteria. Langerhans cells (LC) and keratinocytes (KC) are antigen‐presenting cells that are important in promoting immune responses.

Method: In this study we examined, by means of immunofluorescence, the distribution and numbers of LC and activated KC in biopsies taken from inflamed periodontal sites in HIV+, HIV− patients with CMP.

Results: In the pocket epithelium in both patient groups, basal layer KC expressed HLA‐DR molecules. In the oral gingival epithelium of HIV+ patients, basal layer KC also expressed HLA‐DR molecules and numbers of LC were decreased as compared with HIV− persons.

Conclusion: The findings suggest that the oral gingiva in HIV+ patients may be affected by inflammation.
Adjunctive treatment with subantimicrobial doses of doxycycline: effects on gingival fluid collagenase activity and attachment loss in adult periodontitis
Authors: Golub Lorne M. , McNamara Thomas F. , Ryan Maria E. , Kohut Bruce , Blieden Timothy , Payonk Gregory , Sipos Tibor , Baron Hazen J.
Published: March 2003

Objectives: The therapeutic effects of doxycycline and other tetracyclines in the treatment of periodontitis involve, at least in part, mechanisms that are unrelated to their antimicrobial activity. Previous clinical studies have shown that doxycycline administered orally, at doses below those needed for antimicrobial efficacy, to human subjects with adult periodontitis resulted in significantly reduced collagenase activity in gingival crevicular fluid (GCF) and in extracts of inflamed gingival tissues. The purpose of the present study was to identify clinically effective dosing regimens using subantimicrobial dose doxycycline (SDD) as an adjunctive therapy in patients with adult periodontitis.

Material and Methods: A total of 75 adult men and women qualified for enrollment into the three‐part, placebo‐controlled, double‐blind, parallel‐group study. Patients were stratified based on repeatedly exhibiting pathologic levels of periodontal attachment (ALv) and GCF collagenase activity at several appointments prior to baseline. Patients were administered a scaling and prophylaxis, then 1 of 5 treatment schedules for 12 weeks (part I), followed by a 12‐week period of no drug therapy (part II), a second scaling and prophylaxis, and 12 additional weeks of treatment (part III). Primary determinants of efficacy included reductions in GCF collagenase activity and changes in relative ALv.

Results: 66 patients completed the 1st 12 weeks (part I) of the 3‐part, 36‐week study; 51 patients completed the entire 36‐week study. From baseline to week 12 (part I), treatment with specially formulated SDD capsules (20 mg) 2× daily (1× every 12 h) for up to 12 weeks was shown to significantly reduce GCF collagenase activity and to improve ALv, effects not seen in patients treated with placebo. Continuous drug therapy over the 12‐week treatment period was needed to maintain and maximize the reduction in GCF collagenase and the improvement in ALv. Improvements in periodontal disease parameters occurred without the emergence of doxycycline‐resistant micro‐organisms. In patients administered an “on‐off‐on” regimen of SDD over 36 weeks (parts I–III), essentially no attachment loss occurred in patients receiving the highest of these SDD regimens (20 mg 2× daily during part I and 20 mg 1× daily in part III), whereas patients administered placebo capsules experienced a mean attachment loss of approximately 0.8 mm at the 24‐ and 36‐week time periods.

Conclusions: Doxycycline administered at subantimicrobial doses led to improvements in disease parameters, with no apparent side effects, and appears to have significant potential as an oral adjunctive therapy in the long‐term management of adult periodontitis.
The anesthetic onset and duration of a new lidocaine/prilocaine gel intra‐pocket anesthetic (Oraqix®) for periodontal scaling/root planing
Authors: Friskopp Johan , Nilsson Marie , Isacsson Göran
Published: March 2003

Background: A new non‐injection anesthetic, lidocaine/prilocaine gel (Oraqix®, AstraZeneca) in a reversible thermosetting system, has been developed to provide local anesthesia for scaling/root planing (SRP). The aim of this study was to determine the anesthetic onset and duration of the gel for SRP in patients with periodontitis.

Methods: 30 patients were randomized to either 30 s, 2 min, or 5 min of treatment with the gel prior to SRP of a tooth. The gel was applied to periodontal pockets with a blunt applicator. On completion of the SRP of each tooth (2–3 teeth treated/patient), the patients rated their pain on a 100‐mm visual analogue scale (VAS).

Results: The median VAS pain score was 7.5 mm in the 30‐s group, 28.5 mm in the 2‐min group, and 15.5 mm in the 5‐min group, with a significant difference between the 30‐s and 2‐min groups (p=0.03). In 2 patients in the 5‐min group, but none in the other groups, the SRP was interrupted due to pain. The mean duration of anesthesia measured as pain on probing were 18.1, 17.3, and 19.9 min in the 30‐s, 2‐min, and 5‐min groups, respectively. There were no reports of numbness of the tongue, lip, or cheek, neither were there any adverse local reactions in the oral mucosa. The gel was easy to apply and did not interfere with the SRP procedure.

Conclusion: Oraqix® provides anesthesia after an application time of 30 s, with a mean duration of action of about 17 to 20 min.
Bone morphogenetic protein‐2 stimulates cell recruitment and cementogenesis during early wound healing
Authors: King Gaston N. , Hughes Francis J.
Published: March 2003

Background:The unique action of bone morphogenetic proteins (BMPs) on mineralised tissue formation indicates that BMPs are good candidates for use in stimulating periodontal regeneration. Relatively little is known about the mechanisms of actions of BMPs during periodontal regeneration, although recent evidence from our laboratory suggests that the effects of BMPs may be profoundly influenced by various factors including root surface conditioning, delivery systems and masticatory forces.

Aim:The aim of this study was to investigate the effect of rhBMP‐2 on cell recruitment during periodontal regeneration using a pulse‐chase technique where cells are labelled with a thymidine analogue (BrdU) (pulse) and the migration of their progeny is followed (chase) during early wound healing. The relationship between the rhBMP‐2 influence on cell recruitment from the periodontal ligament (PDL) and its ability to stimulate cementogenesis was also evaluated.

Method:The buccal aspect of the distal root of the first molar was denuded of its PDL, cementum and superficial dentine through a bony window created in the mandible of 64 Wistar rats under general anaesthesia. Test animals were treated with 10 μL of 500 μg/ml rhBMP‐2 in a collagen membrane sponge (n=32) and control defects received 10 μl of saline in a collagen sponge (n=32). All animals received an intraperitoneal single pulse injection of 40 mg/kg BrdU label 2 days postoperatively. Groups of test and control animals (n=8) were killed 2 hours later on day 2 and at 4, 7 and 10 days postoperatively. Mandibles were processed for histological examination.

Results:The results show that rhBMP‐2 had a profound effect on proliferation and migration of cells in the adjacent and deeper aspects of the PDL at 7 and 10 days post periodontal wounding (p<0.05). Significantly greater new cementum formation occurred in the test group at 10 days (p=0.03).

Conclusion:This study shows that following periodontal wounding rhBMP‐2 stimulates cell recruitment by increasing proliferation and migration of cells from the adjacent unwounded PDL into the wounded area, thus promoting periodontal regeneration by increasing new cementum formation.
Experimental peri‐implant mucositis in man
Authors: Zitzmann N. U. , Berglundh T. , Marinello C. P. , Lindhe J.
Published: March 2003

Objectives: The purpose of this study was to examine reactions of gingiva and peri‐implant mucosa (PiM) to de novo plaque accumulation in humans.

Material and Methods: Prior to the start of the study, which included 12 partially edentulous subjects, a 3‐week plaque control program was performed. Ethical approval was granted by the local ethics committee. On day 0, 2 soft tissue biopsies were harvested, 1 from a tooth and 1 from an implant site in every subject. After 3 weeks of undisturbed plaque accumulation (day 21), 2 additional biopsies were obtained from the gingiva and PiM in each subject. The tissue samples, each 4×4 mm in size, were snap frozen and prepared for immunohistochemical analysis.

Results: The size of the infiltrate (ICT) in the day 0 biopsies, was about 0.03 mm2 in both the gingiva and PiM. At the end of the plaque accumulation period, the size of the lesion had significantly increased in both groups and occupied an area of 0.26 mm2 in the gingiva and 0.14 mm2 in PiM. In the biopsies presenting day 0, the proportions of the various cell populations examined were similar in the gingiva and in PiM. The tissue fractions of almost all types of cells increased during the 3 weeks, but the mean change for each cell type was greater in the gingiva than in PiM. The CD3/CD19 ratio decreased in the gingiva between day 0 and 21, but increased in PiM.

Conclusion: The results of the present study indicated that plaque accumulation induced an inflammatory response characterized by increased proportions of T‐ and B‐cells in the ICT of both the gingiva and the PiM. Although not statistically significant, the host response in the gingiva tended to be more pronounced than in the peri‐implant mucosa.
Studies on the effect of polyvinyl pyrrolidone on the activity of chlorhexidine mouthrinses: plaque and stain
Authors: Claydon N. , Addy M. , Jackson R. , Smith S. , Newcombe R. G.
Published: March 2003

Background, aims: Polyvinyl pyrrolidone (PVP) was shown in vitro to reduce chlorhexidine induced, dietary staining without affecting the uptake of the antiseptic to the test substrate. The aim of these studies in vivo was to determine whether PVP affected plaque and dietary staining by a low concentration chlorhexidine rinse.

Methods: The plaque and stain studies used a double blind, randomised 6, treatment crossover design involving healthy subjects with a high standard of oral hygiene and gingival health. The rinse formulations under test were: (A) aqueous alcohol (placebo control), (B) 0.03% chlorhexidine, (C) 0.06% chlorhexidine, (D) 0.06% chlorhexidine+1.2% PVP, (E) 0.06% chlorhexidine+5% PVP, (F) 0.06% chlorhexidine+10% PVP. In the plaque study, on day 1 of each period, subjects were rendered plaque free and then rinsed with 15 ml of the test rinse for 60 s. No further tooth cleaning was performed and subjects returned 24 h later for plaque scoring by area. In the stain study, on day 1 of each period, the tongue and teeth of each subject were rendered stain free. Subjects then rinsed under supervision for 60 s with 15 ml of the allocated rinse 8× a day between 09:00 h and 17:00 h for 3 days. Immediately after each rinse with the test formulation, subjects rinsed for 120 s with 15 ml of warm black tea. Subjects were requested to also drink at least 5 cups of tea or coffee per day. On day 4, stain was scored by area and intensity from designated teeth and dorsum of the tongue. Washout periods were at least 7 days in both studies.

Results: Plaque areas were greatest with placebo and least with 0.06% chlorhexidine. Plaque scores increased with increasing concentrations of PVP in the 0.06% chlorhexidine rinse and were significantly higher than 0.06% chlorhexidine without PVP rinse. Tooth stain areas were comparable for placebo, 0.03% and 0.06% chlorhexidine rinses, but significantly reduced with the PVP/chlorhexidine rinses compared to the 0.06% chlorhexidine rinse. Tooth stain intensity was significantly increased with 0.06% chlorhexidine rinses compared to placebo and chlorhexidine/PVP rinses. Tongue stain area and intensity were significantly reduced with 5% and 10% PVP/chlorhexidine rinses compared to 0.06% chlorhexidine rinse.

Conclusion: PVP, at the concentrations tested, reduced the stain propensity of a 0.06% chlorhexidine rinse but at the expense of some loss of plaque inhibition.
CD9 and HLA‐DR expression by crevicular epithelial cells and polymorphonuclear neutrophils in periodontal disease
Authors: Bisson‐Boutelliez C. , Miller N. , Demarch D. , Bene M. C.
Published: March 2003

Background, aims: The composition of gingival crevicular fluid (GCF) is likely to reflect inflammatory modifications that take place in the gingiva during periodontal diseases.

Method: In this study, GCF was collected at 3 different sites from 23 periodontal patients. The sites were assessed to be healthy, presenting gingivitis or periodontitis. 10 healthy individuals without any form of periodontal disease formed the control group and were sampled at one site each. The cell content of GCF was collected using Durapore Millipore strips, and 2 types of cells were studied: epithelial cells (EC) and polymorphonuclear neutrophils (PMN). The expression of CD9 and HLA‐DR within or on the surface of these cells was studied in immunofluorescence on cytospin smears.

Results: Both CD9 and HLA‐DR expression on EC differed significantly from control subjects, and the latter decreased according to the severity of the pathology. None of the PMN found in controls expressed CD9 or HLA‐DR. However, in periodontal patients, the expression of HLA‐DR within PMNs was detectable and increased according to the severity of lesions. CD9 expression on PMNs also increased with inflammation.

Conclusion: This study shows that clinically healthy sites of periodontal patients already present signs of immunological activation characterised by a down modulation of HLA‐DR expression on EC and an upregulation of these 2 molecules in PMN.
Validation of smoking status in clinical research into inflammatory periodontal disease
Authors: Scott D. A. , Palmer R. M. , Stapleton J. A.
Published: March 2003

Background: Tobacco smoking is an accepted risk factor for periodontal disease. Most studies in the periodontal literature rely on reported smoking habits which can be unreliable. This review specifically addresses this problem.

Methods: Methods of assessing tobacco smoke exposure, variation in individual smoking habits, classification of former/ex‐smokers, and validation of abstinence in smoking cessation studies receive attention.

Discussion: Additionally, clinical studies that have examined periodontal health in subjects with validated smoking status are discussed.
IL‐8 and TNF‐α from peripheral neutrophils and acute‐phase proteins in periodontitis
Authors: Fredriksson M. , Bergström K. , Åsman B.
Published: March 2003

Objective: In other studies, we have found deviant functions in peripheral neutrophils in periodontitis. The aim here was to study (1) the release of cytokines, IL‐8 and TNFα, from neutrophils in 15 treated periodontitis patients and pair‐matched controls as well as (2) the effects of cigarette smoking.

Material and methods: Cytokines released in the incubation medium from un‐stimulated and Fcγ‐R‐stimulated neutrophils and some acute‐phase reactants were measured with ELISA.

Results: Non‐smoking patients had trends for lower TNFα release compared to non‐smoking controls, while corresponding trends were rather similar for Il‐8. Smoking had a moderate but inconsistent effect on the release of both cytokines. However, in patients, the ratio between stimulated/un‐stimulated release of Il‐8 was significantly lowered by smoking (p<0.03). The parameters of inflammation in plasma differed only slightly between patients and controls, indicating that periodontal disease in a quiet phase has a negligible systemic effect with the possible exception for a higher IL‐8 level. In contrast, smoking had significant systemic effect on the neutrophil count and IgG levels.

Conclusions: Release of IL‐8 and TNF‐α from peripheral neutrophils and various parameters of inflammation in plasma seem to be affected more by cigarette smoking than periodontal disease.
Distribution of erm(F) and tet(Q) genes in 4 oral bacterial species and genotypic variation between resistant and susceptible isolates
Authors: Chung Whasun O. , Gabany Joseph , Persson G. Rutger , Roberts Marilyn C.
Published: March 2003

Background: Bacteroides forsythus, Porphyromonas gingivalis and Prevotella intermedia are Gram‐negative anaerobic bacteria that are currently considered potential periopathogens. Prevotella nigrescens has recently been separated from P. intermedia and its rôle in periodontitis is unknown. The erm(F) gene codes for an rRNA methylase, conferring resistance to macrolides, lincosamides and streptogramin B (MLSB), and the tet(Q) gene for a ribosomal protection protein, conferring resistance to tetracycline. The presence of these resistance genes could impair the use of antibiotics for therapy.

Purpose: The aim of this study was to determine the carriage of erm(F) and tet(Q), and genetic variability of 12 Porphyromonas gingivalis, 10 Prevotella intermedia, 25 Prevotella nigrescens and 17 Bacteroides forsythus isolates from 9 different patient samples.

Methods: We used polymerase chain reaction (PCR) for detecting antibiotic resistance genes, and pulsed‐field gel electrophoresis (PFGE) for detecting genetic variability among the isolates.

Results: Thirty‐one (48%) isolates were resistant to both erythromycin and tetracycline and carried the erm(F) and tet(Q) genes, eight (13%) were tetracycline resistant and carried the tet(Q) gene, 9 (14%) were erythromycin resistant and carried the erm(F) gene, and 12 (19%) isolates did not carry antibiotic resistance genes. PFGE was used to compare isolates from the same patient and isolates from different patient samples digested with XbaI. No association was found between antibiotic resistance gene carriage and PFGE patterns in any species examined. All isolates of the same species from the same patient had highly related or identical PFGE patterns. Isolates of same species from different patients had unique PFGE pattern for each species tested.

Conclusion: All isolates of the same species from any one patient were genetically related to each other but distinct from isolates from other patients, and 66% of the patients carried antibiotic resistant isolates, which could impair antibiotic therapy.
Collagenase‐2 (MMP‐8) and collagenase‐3 (MMP‐13) in adult periodontitis: molecular forms and levels in gingival crevicular fluid and immunolocalisation in gingival tissue
Authors: Kiili M. , Cox S. W. , Chen H. W. , Wahlgren J. , Maisi P. , Eley B. M. , Salo T. , Sorsa T.
Published: March 2003

Aim: To determine the cellular and molecular forms of MMP‐8 (collagenase‐2) and MMP‐13 (collagenase‐3) associated with chronic adult periodontitis by examining the species present in gingival crevicular fluid (GCF) and enzyme distribution in gingival tissue.

Methods: 30‐s GCF samples were collected directly from the periodontal pockets of 12 untreated patients using filter paper strips. After elution into buffer, the samples were examined by Western immunoblotting with polyclonal antibodies for MMP‐8 and MMP‐13 and quantification by scanning image analysis. Individual band intensities were expressed as a percentage of total sample absorbance and mean patient values were calculated. Gingival tissue from 6 patients was fixed in formalin and embedded in paraffin wax. MMP‐8 and MMP‐13 were localised using the same antibodies and an avidin‐biotin‐peroxidase detecting system. Double staining was performed with a contrasting substrate reaction.

Results: The majority of MMP‐8 staining in pre‐treatment GCF was present in 80, 75 and 60 kD bands corresponding to prepro‐, pro‐ and active forms of PMN‐type enzyme. 43 and 38 kD bands evidently represented active, fibroblast‐type MMP‐8. Immunoreactivities at >100 kD and 30 kD were probably enzyme‐inhibitor complex and degraded fragments, respectively. MMP‐13 was seen mainly as 60 kD proenzyme with some 40 kD active enzyme and a small proportion of >100 kD complex. The percentages of MMP‐8 PMN‐type enzyme and MMP‐13 proenzyme bands correlated significantly with gingival and bleeding indices (p<0.05). Immunohistochemistry demonstrated MMP‐8 in PMNs, sulcular epithelial and also plasma cells in inflamed gingival connective tissue. MMP‐13 immunoreactivity was detected in the sulcular epithelium and in macrophage‐like cells.

Conclusion: Multiple species and elevated levels of both MMP‐8 and MMP‐13 from many rather than single cellular sources in the diseased periodontium are identified in untreated periodontitis GCF and active forms contribute to GCF collagenase activity.
Can application of exogenous fibronectin enhance periodontal regeneration?
Authors: Wagle Jason E. , Virji Adi S. , Williams Karen B. , Rapley John W. , MacNeill Simon R. , Cobb Charles M.
Published: March 2003

Background: Although fibronectin (FN) is an important extracellular glycoprotein involved in periodontal wound healing, it is not clear whether the application of exogenous fibronectin (ExoFN) offers any clinical benefit. The purpose of this preliminary in vitro study was to determine the binding of FN from three different sources, viz. endogenous EDTA‐plasma, endogenous serum and exogenous commercial purified human fibronectin in PBS buffer, to demineralized and non‐demineralized root powder.

Method: The binding of FN to a known quantity of mineralized and non‐demineralized root powder by overnight incubation at 15°C was studied by enzyme immunoassay (EIA) technique. The criteria for optimal performance of EIA procedure for the determination of FN was established. Particle size of powdered root structure was standardized using a Vibratory Sieve Shaker.

Results: The EDTA‐plasma and the serum FN exhibited binding of (17.8 ± 2.1 µg) and (6.5 ± 4.5 µg), respectively, to the non‐demineralized root powder. However, the binding was only significant for the EDTA‐plasma FN (p < 0.01) when compared to controls. In the demineralized group there was no ascertainable binding of FN from either endogenous or exogenous sources. ExoFN in buffer exhibited no binding at all to the non‐demineralized or demineralized root powder.

Conclusion: The preliminary data suggest that additional plasma and serum factors may facilitate the binding of FN to root powder. High levels of FN in blood do not necessarily indicate that FN is available for binding to the root surface during periodontal surgery.
Investigation of an IL‐2 polymorphism in patients with different levels of chronic periodontitis
Authors: Scarel‐Caminaga Raquel M. , Trevilatto Paula C. , Souza Ana P. , Brito Rui B. , Line Sergio R. P.
Published: March 2003

Background: Interleukin‐2 (IL‐2) is a pro‐inflammatory cytokine derived from Th1 cells. This cytokine is involved in B‐cell activation and stimulates macrophages, natural killer cells, T‐cell proliferation and osteoclast activity. IL‐2 has been also implicated in the stimulation of osteoclast activity in bone resorption.

Objective: In this study the relationship between the polymorphism − 330 (T→G) in the IL‐2 gene and different levels of chronic periodontal disease was investigated.

Material and Methods: DNA was extracted from buccal epithelial cells of 113 unrelated adult individuals acting as controls and with different levels of periodontitis. The PCR‐RFLP technique was used to investigate the polymorphism in the promoter of IL‐2 gene.

Results: When comparing the data of three groups of patients (Control, Moderate and Severe) we did not find significant differences between the studied IL‐2 polymorphism and severity levels of PD. However, when the Control and Moderate phenotypes were grouped together and compared with genotypes TT vs. TG/GG, a significant difference was observed.

Conclusion: We conclude that the − 330 (T→G) polymorphism in the IL‐2 gene is associated with the severity of periodontal disease. The results presented in this study suggest an active role of IL‐2 in the pathogenesis of periodontal disease.
Tobacco smoking and risk for periodontal disease
Authors: Bergström Jan
Published: March 2003

Objective: The magnitude of risk for periodontal disease associated with smoking was investigated by exploring the interrelationships between definition of disease, prevalence and relative risk in a population of dentally aware individuals.

Materials and Methods: A total of 133 smokers and 242 non‐smokers in the age range 20–69 years served as the database. Criteria based on clinical probing of pocket depth and radiographic measurement of bone height were used for the purpose of disease definition. Various pocket frequency cutoff points for two probing depth levels, 5 and 6 mm, and, in addition, the 30th, 25th, and 20th percentiles of the bone height distribution were alternately selected as criteria.

Results: Disease definition had an impact on the prevalence, and the relative risk varied as a function of the prevalence. For a broad definition of disease such as 1% of pockets 5 mm, the prevalence for smokers was approximately twice the prevalence for non‐smokers and the odds ratio (OR) was 3.0. A narrower definition such as 15% of pockets 5 mm resulted in decreased prevalences for both smokers and non‐smokers and an OR of 12.1. Increasing exposures correlated with greater magnitudes of risk. Heavy exposure was associated with greater risk than light exposure. For the combination of a narrow disease definition and heavy exposure, the relative risk was considerable (OR 9.8–20.3).

Conclusion: Smoking‐associated relative risk is dependent on definition of disease and prevalence. Given other factors, a narrow definition will result in a low prevalence and a high risk and, vice versa, for a broader definition, prevalence will be high and the risk moderate.
Clinical evaluation of an Er:YAG laser combined with scaling and root planing for non‐surgical periodontal treatment
Authors: Schwarz Frank , Sculean Anton , Berakdar Mohammad , Georg Thomas , Reich Elmar , Becker Jürgen
Published: March 2003

Objectives: The purpose of the present controlled clinical trial was to compare the treatment of advanced periodontal disease with a combination of an Er:YAG laser (KEY II®, KaVo, Germany) and scaling and root planing with hand instruments (SRP) to laser alone.

Material and methods: Twenty healthy patients with moderate to advanced periodontal destruction were randomly treated in a split‐mouth design with a combination of an Er:YAG laser and SRP (test) or with laser (control) alone. The used energy setting for laser treatment was 160 mJ/pulse at a repetition rate of 10 Hz. Prior to treatment and 3, 6 and 12 months later the following parameters were evaluated by a blinded examiner: Plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR) and clinical attachment level (CAL). Subgingival plaque samples were taken at each appointment and analysed using darkfield microscopy for the presence of cocci,‐non‐motile rods, motile rods and spirochetes. No statistical significant differences in any of the investigated parameters between both groups were observed at baseline.

Results: Initially, the plaque index was 1.0 ± 0.6 in both groups. At the 3‐month examination the plaque scores were markedly reduced and remained low throughout the study. A significant reduction of the GI and BOP occurred in both groups after 3, 6 and 12 months (P < 0.05, P < 0.05, respectively). The mean PD decreased in the test group from 5.2 ± 0.8 mm at baseline to 3.2 ± 0.8 mm after 12 months (P < 0.05) and in the control group from 5.0 ± 0.7 mm at baseline to 3.3 ± 0.7 mm after 12 months (P < 0.05). The mean CAL decreased in the test group from 6.9 ± 1.0 mm at baseline to 5.3 ± 1.0 mm after 12 months (P < 0.05) and in the control group from 6.6 ± 1.1 mm at baseline to 5.0 ± 0.7 after 12 months (P < 0.05). Both groups showed a significant increase of cocci and‐non‐motile rods and a decrease in the amount of motile rods and spirochetes.

Conclusion: In conclusion, the present results have indicated that: (i) non‐surgical periodontal therapy with both an Er:YAG laser + SRP and an Er:YAG laser alone may lead to significant improvements in all clinical parameters investigated, and (ii) the combined treatment Er:YAG laser + SRP did not seem to additionally improve the outcome of the therapy compared to Er:YAG laser alone.
Clinical significance: an introduction
Authors: Jeffcoat Marjorie
Published: March 2003

Jeffcoat M: Clinical significance: an introduction. J Clin Periodontol 2002; 29 (Suppl 2): 5. © Blackwell Munksgaard, 2002.
Analysis strategies for longitudinal attachment loss data
Authors: Beck James D. , Elter John R.
Published: March 2003

Abstract – The purpose of this invited review is to describe and discuss methods currently in use to quantify the progression of attachment loss in epidemiological studies of periodontal disease, and to make recommendations for specific analytic methods based upon the particular design of the study and structure of the data. The review concentrates on the definition of incident attachment loss (ALOSS) and its component parts; measurement issues including thresholds and regression to the mean; methods of accounting for longitudinal change, including changes in means, changes in proportions of affected sites, incidence density, the effect of tooth loss and reversals, and repeated events; statistical models of longitudinal change, including the incorporation of the time element, use of linear, logistic or Poisson regression or survival analysis, and statistical tests; site vs person level of analysis, including statistical adjustment for correlated data; the strengths and limitations of ALOSS data. Examples from the Piedmont 65+ Dental Study are used to illustrate specific concepts. We conclude that incidence density is the preferred methodology to use for periodontal studies with more than one period of follow‐up and that the use of studies not employing methods for dealing with complex samples, correlated data, and repeated measures does not take advantage of our current understanding of the site‐ and person‐level variables important in periodontal disease and may generate biased results.
A comparison of retention and the effect on caries of fissure sealing with a glass‐ionomer and a resin‐based sealant
Authors: Poulsen Sven , Beiruti Nabil , Sadat Nada
Published: March 2003

Abstract – Objective: To compare the retention and the caries preventive effect of a glass‐ionomer developed for fissure sealing (Fuji III®) and a chemically polymerized resin‐based fissure sealant (Delton®). Design: A split mouth randomized design using contralateral teeth. Setting: WHO Regional Demonstration, Training and Research Center for Oral Health, Damascus, Syrian Arab Republic. Sample and methods: 179 children, 7 years old at the start of the study, were recruited from schools close to the Center. Only children with at least one pair of permanent first molars that were caries free or only had incipient lesions were included in the study. Follow‐up examinations for sealant retention were done after 6 months, 1 year, 2 years and 3 years. The number of children available for reexamination was 129 (after 6 months); 121 (after 1 year); 115 (after 2 years) and 116 (after 3 years). Four dental hygienists were trained in the sealant procedures and did approximately one fourth of the sealants each. Results: After 3 years the glass‐ionomer sealant was completely lost in almost 90% of the teeth compared to less than 10% of the resin sealed teeth. After 3 years the relative risk of a tooth sealed with glass‐ionomer over that of a tooth sealed with resin was 3.38 (95% CL: 1.98; 5.79). This finding was consistent over type of tooth. Conclusions: The glass‐ionomer sealant tested in the present study had poorer retention and less caries protective effect than the resin‐based sealant used.
Effect of contact media on the diagnostic quality of electrical resistance measurements for occlusal caries
Authors: Mosahebi Negin , Ricketts David Nigel James
Published: March 2003

Background: Electrical resistance measurements have been used for the diagnosis of occlusal caries. Both site and surface‐specific techniques have been described, the latter more suited to clinical trials or epidemiological surveys. For surface‐specific measurements the tooth is dried and a contact medium drawn along the fissure pattern to provide an electrical contact between a probe tip and the tooth surface.

Objectives: Different contact media have been used and it was the aim of this study to investigate whether different contact media could influence the diagnostic accuracy and repeatability of surface‐specific electrical resistance measurements.

Methods: Electrical resistance readings were taken on 99 molar teeth using saline, KY jelly, toothpaste or dental prophylaxis paste. Readings were repeated on 44 randomly selected teeth. The teeth were serially sectioned and visually examined to establish the deepest lesion if present.

Results: The Student t‐test showed that there were statistically significant differences between readings taken with different contact media, with the exception of toothpaste and prophylaxis paste, where no difference was found. The strongest relationship between histology and resistance reading was achieved with KY jelly (r = 0.559). The optimum sensitivity and specificity achieved was 0.59 and 0.86, respectively (resistance cut‐off 0.1 MΩ). ROC analysis showed that the diagnostic performance of saline was significantly inferior to the other contact media (P < 0.05). Limits of agreement were used to assess repeatability which were acceptable for all media except toothpaste.

Conclusions: Differences were found between electronic resistance readings taken with different contact media. KY jelly was found to produce the best overall diagnostic performance and should be the standard material used for surface‐specific measurements.
Regulation of the cutaneous allergic reaction by humidity
Authors: Hosoi Junichi , Hariya Takeshi , Denda Mitsuhiro , Tsuchiya Toru
Published: March 2003

Humidity is 1 of the environmental factors which regulate skin conditions. Effects of humidity on the cutaneous immune reaction were examined. Contact hypersensitivity to 2,4,6‐trinitrochlorobenzene was elicited in C57BL/6 mice. The reaction was greater in mice housed under low humidity conditions (about 10%) for 2 days, at either the induction or elicitation phase, than in mice housed under rather high humidity conditions (80%). After housing under controlled humidity for 2 days, the number of I‐A positive cells was 16% higher in the epidermis exposed to the dry condition. The increased population of FITC‐positive cells were in regional lymph nodes after painting of FITC during housing under lower humidity. Our study demonstrated that the cutaneous immune reaction is regulated by environmental humidity and suggested 2 possible mechanisms, i.e., increase in Langerhans cells and increased penetration of allergen with low humidity.