bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytokine release by osteoblast‐like cells cultured on implant discs of varying alloy compositions
Authors: Spyrou Pericles , Papaioannou Stelios , Hampson Geeta , Brady Ken , Palmer Richard M. , McDonald Fraser
Published: March 2003

Abstract: Objective: The aims of this study were (i) to assess the morphological features of osteo‐blast‐like, osteosarcoma cells (cell line SaOS‐2) cultured on implant surfaces of varying alloys and (ii) to evaluate the biological activity of these cells, following their adhesion onto these surfaces.

Material and methods: SaOS‐2 cells (6 × 104) were grown on titanium discs (diameter 30 mm), each with a surface of differing composition and roughness (commercially pure titanium, titanium‐aluminium‐vanadium alloy, oxide‐blasted titanium and Astra‐Tech special treatment titanium; the alloys are directly comparable with those used to construct implants). The cells were grown for time periods of 1, 3, 5 and 7 days, the media were collected and the cells were fixed with 2.5% glutaraldehyde. The media were then assayed (using enzyme‐linked immunosorbant assay) for the levels of interleukin (IL)‐1, interleukin‐6, interleukin‐18 and osteoprotegerin (OPG) produced by the cells. The discs, with the cells fixed on them, were viewed under scanning electron microscopy (SEM, × 2.0 k) to evaluate cell morphology.

Results: Following attachment, the cells changed their morphology and released local factors known to activate osteoclasts. Commercially pure titanium stimulated the cells the most and titanium‐aluminium‐vanadium alloy the least. All implant materials stimulated production of IL‐1, IL‐6, IL‐18 above that produced by cells grown on Petri dishes (polystyrene). The titanium‐aluminium‐vanadium alloy allowed cell attachment but levels of IL‐1 in this medium were significantly lower (31.5 ± 5.2 pg/ml on same day) than cultures with pure titanium (201.8 ± 11.5 pg/ml at day 5). The same pattern was observed with the IL‐6, IL‐18, and OPG with polystyrene appearing to stimulate most production of OPG. Titanium‐aluminium‐vanadium produced the least biological response.
The microflora recovered from the outer‐surfaces of the Frialit‐2 implanto‐prosthetic connector
Authors: Buchmann Rainer , Khoury Fouad , Pingel Dieter , Lange Dieter E.
Published: March 2003

Abstract: The aim of the present investigation was to examine the outer‐surface microbiota of the prosthetic connector of Frialit‐2 implants, and to compare the microbial findings with the peri‐implant parameters 2 years after functional loading. In 16 implant‐treated patients (55.8 ± 9.5 years) the outer‐surface micro‐organisms of the prosthetic connectors were determined in 32 Frialit‐2 implants. The functional loading time of the prosthetic suprastructures was 24.1 ± 13.8 months on average. After removal of the implant‐supported restoration, microbial samples were obtained from the outer‐surfaces of the Frialit‐2 prosthetic connector. The microbial plaque samples were specified on CDC‐blood agar as percentages of the total cultivable flora. Actinobacillus actinomycetemcomitans was semiquantitively determined on TSBV‐agar in CFU/ml. The microbial plaque samples were dominated by Actinomyces israelii (68.8%), Eubacterium lentum (56.3%) and Veillonella parvula (43.8%) with proportions ranking between 3.9% (V. parvula) and 11.1% (A. israelii). The most frequently detected gram‐negative microorganisms were Fusobacterium nucleatum (87.5%), Porphyromonas gingivalis (81.3%), and Peptostreptococcus micros (68.8%) with enhanced proportions for P. gingivalis (11.4%) and P. micros (11.4%). No statistical significant correlation could be established between the microbiota present on the outer‐surfaces of the F2‐connector and the peri‐implant parameters examined. The outer‐surface microflora recovered from the implanto‐prosthetic‐connector of Frialit‐2 implants reveals a colonization with gram‐positive bacteria and potentially harmful gram‐negative micro‐organisms that were frequently detected, but present at low levels. After 2 years of restorative loading, the outer‐surface microbial colonization is compatible with peri‐implant soft tissue health.
Explanatory models for clinical and subjective indicators of periodontal disease in an adult population
Authors: Unell Lennart , Söderfeldt Björn , Halling Arne , Birkhed Dowen
Published: March 2003

Background: The aim of this study was to analyze indicators of periodontal disease using: (1) community periodontal index of treatment needs (CPITN), (2) subjectively reported change of front teeth position, and 3) subjectively reported gingival bleeding.

Method: These 3 indicators were used in models with explanatory variables from 4 domains: (A) socio‐economic attributes, (B) general health and health‐related lifestyle, (C) dental attitudes and behaviors, and (D) dental status expressed as (number of teeth and DFT) for the clinically‐determined dependent variables. In 1992, the study was carried out cross‐sectionally in all 50‐year olds in 2 Swedish counties using a questionnaire (n=6343) and clinical investigation of a 20 % subsample (n=1040).

Results: Multiple and logistic regression analysis showed that explanatory patterns varied for the clinical and subjective indicators. Use of tobacco had strong effects in all models as did high care utilization. There were few associations with socio‐economic attributes. The 2 subjective indicators “changed front position” and “gingival bleeding” associated with attitudes, behaviors and subjective health. Number of teeth and DFT covaried with clinical indicators.

Conclusions: The main conclusions from this study are: (1) that it is possible to find multivariate models with acceptable goodness of fit for prediction of occurrence of periodontal indicators, and (2) that the lack of relation between social attributes and the disease gives arguments for a biological provenance of periodontitis.
Concentration of 3 tetracyclines in plasma, gingival crevice fluid and saliva
Authors: Sakellari D. , Goodson J. M. , Socransky S. S. , Kolokotronis A. , Konstantinidis A.
Published: March 2003

Background: Systemically‐administered tetracyclines have been used widely for treatment of periodontal diseases with little understanding of their delivery characteristics to periodontal tissues. This study was designed to measure concentrations of 3 tetracyclines in gingival crevice fluid (GCF), plasma and saliva of following systemic administration.

Method: The concentration of tetracycline (TC), minocycline (MN) and doxycycline (DX) was measured in gingival crevice fluid (GCF), plasma and saliva of 20 subjects following single sequential standard oral systemic doses. Gingival crevice fluid concentration was measured at 4 sites (2 shallow and 2 deep) before administration, and at 1 h and 2 h following administration. Plasma and saliva concentrations were measured from in samples at the same time points. No antibacterial activity was detected before administration. The highest concentrations were measured 2 h after administration.

Results: The average concentrations at 2 h were highest in plasma (TC=1.02, MN=2.18, DX=2.35 μg/ml). Intermediate concentrations were measured in GCF (TC=0.61, MN=1.49, DX=1.65 μg/ml). Saliva concentrations (TC=0.09 MN=0.31, DX=0.47 μg/ml) were the lowest of the 3 fluids monitored. Data are presented indicating that the average GCF concentration of systemically administered tetracyclines is less than the that of plasma concentration. The concentration of tetracyclines in GCF was strongly associated with plasma concentration, indicating a primary rôle of drug absorption in the delivery of these systemically administered antibiotics to the site of action in periodontal therapy. The average GCF concentration in individuals varied widely (between 0 and 8 μg/ml) with approximately 50% of samples not achieving levels of 1 μg/ml.

Conclusions: These observations suggest that poor absorption of orally‐administered tetracyclines in many individuals may account for much of the variability in clinical response to antibiotics observed in practice.
After‐effects of stress on crevicular interleukin‐1ß
Authors: Deinzer Renate , Kottmann Wulf , Förster Peter , Herforth Armin , Stiller‐Winkler Renate , Idel Helga
Published: March 2003

Background: In a previous study, we found stress to increase crevicular interleukin‐1ß (Il‐1ß) secretion induced by supragingival plaque. While in that study, stress and plaque were presented concomitantly, we now wondered whether a consecutive presentation of these 2 factors would still exert stress effects.

Method: 39 medical students participated in the study; 18 took part in a major exam while the remaining 21 served as controls. From the day after the last exam, students neglected oral hygiene in 2 antagonistic quadrants for 21 days (experimental gingivitis), while they maintained perfect hygiene at the remaining sites. Crevicular fluid samples were taken at days 0, 5, 8, 15, 18, and 21 of experimental gingivitis.

Results: A significant effect of pre‐exposure to academic stress on crevicular Il‐1ß concentration was found (area under the curve: p=0.042), the effect size, however, being smaller than in our previous study when stress and plaque were presented concomitantly.

Conclusions: It is concluded that pre‐exposure to stress may persistently alter the immunological effects of microbial challenge to the periodontium.
Studies in vitro of abrasion by different manual toothbrush heads and a standard toothpaste
Authors: Dyer D. , Addy M. , Newcombe R. G.
Published: March 2003

Background: Loss of dentine at the buccal cervical region of teeth has a multifactorial aetiology. However, a considerable amount of circumstantial evidence, supported by laboratory experiments, implicates toothbrushing with toothpaste as a consistent factor. Most interest has centred around the abrasivity of toothpastes, particularly since a toothbrush alone has negligible effects on dentine. The influence of filament stiffness on toothpaste abrasion was the subject of some studies, mostly at least 2 decades ago, and produced conflicting conclusions. Numerous changes to toothbrush design and construction have taken place in recent years.

Aims:

The aim of this study was to measure the abrasion of a standard substrate, acrylic, by a standard toothpaste carried on modern brands of toothbrushes classified by manufacturers as hard (3 brands), medium (3 brands) and soft (6 brands).

Method: The substrate was brushed for 20,000 strokes with at least 6 heads from each brand. Measurements of substrate loss were made at 5000 stroke increments by profilometry.

Results: Substrate loss for all brushes showed a pattern of abrasion which was to a first approximation linear. Overall, hard brushes caused least abrasion and soft brushes the most, with differences between groups being significant. Within‐group differences between brands reached significance for soft and medium brushes but not hard brushes.

Conclusions: The results could be explained by increased retention of toothpaste by smaller diameter filaments and denser tufts on soft brushes and the greater flexion of filaments increasing the area of contact with the surface. Calculations on the clinical outcome of these data in vitro indicate that toothbrushing with toothpaste alone would produce minimal damage to dentine even over many years. Differences between brushes therefore are probably of little clinical significance. Certainly, the data do not support the use of hard brushes, particularly in view of the potential detrimental effects to gingival tissues.
A retrospective radiographic outcome assessment study of intra‐bony defects treated by osseous surgery or by bone graft procedures
Authors: Persson G. Rutger , Falk Hanne , Laurell Lars
Published: March 2003

Background: Intra‐bony defects remain a significant therapeutic problem in periodontal therapy. Various non‐surgical and surgical treatment modalities are being used. The long‐term stability following treatment of intra‐bony defects is poorly documented.

Objectives:

To assess changes in intra‐bony defects after either osseous surgery or open flap debridement in combination with grafting procedures with demineralized freeze‐dried bone allografts (DFDBA).

Method: Pre‐ and post‐surgical computer digitized images of intra‐oral radiographs from 60 patients who had received periodontal surgery to manage intra‐bony defects were analyzed by linear measurements.

Results: 36 patients were treated with osseous surgery and 24 had received flap procedures and grafting with DFDBA. Post‐surgical radiographs were obtained on average after 4.8 years (SD±2.8) and after 9.6 years (SD±3.6). A minor mean bone fill of 0.0 mm (SD±0.8) for osseous surgery sites and 0.5 mm (SD±0.9) for DFDBA sites, was noticed, but this gain was within the margin of measurement errors. Osseous surgery and modified Widman flap procedures with DFDBA resulted in crestal resorption, on average 1.7 mm (SD±1.1) and 1.5 mm (SD±1.5) and remaining mean defect depth of 2.0 mm (SD±1.4) and 2.5 mm (SD±1.6), respectively.

Conclusions: Bone changes following bone graft procedures with DFDBA did not differ from those following osseous surgery, and neither procedure resulted in defect resolution with bone fill. It was also concluded that over the study period, stable treatment results were obtained as a result of both osseous surgery and modified Widman flap procedures with adjunct DFDBA.
Clinical benefits of oral irrigation for periodontitis are related to reduction of pro‐inflammatory cytokine levels and plaque
Authors: Cutler Christopher W. , Stanford Thomas W. , Abraham Celeste , Cederberg Robert A. , Boardman Thomas J. , Ross Candy
Published: March 2003

Background: Although a growing body of evidence indicates that oral irrigation with water has therapeutic benefits in periodontitis, the mechanisms of action have not been elucidated. The aims of this study were: (1) to analyze the effects of oral irrigation (Water Pik® Oral Irrigator) on the clinical signs of adult periodontitis (AP) and on the levels of interleukin‐1β (IL‐β), prostaglandin‐E2 (PGE2), interleukin‐10 (IL‐10) and interferon‐γ (IFN‐γ) in GCF, and (2) to analyze the influence of the periodontitis‐related IL‐1 genotype (IL‐1GT) on these variables.

Method: A single‐center, blinded study in otherwise healthy humans (n=52) with localized mild to moderate AP was carried out, using the following groups: group A (n=12), no oral hygiene for 14 days; group B (n=20), routine oral hygiene (ROH) for 14 days; group C (n=20), supra‐gingival oral irrigation plus ROH for 14 days. Group A patients were crossed‐over to group C for 14 days (=day 28) after a professional prophylaxis. Group assignment was randomized by a coin toss, with the exception of group A subjects, who were self‐selected as per recommendations of the internal review board for human subjects. GCF was sampled from 3 study teeth per patient and analyzed for IL‐1β, PGE2, IL‐10 and IFNγ by ELISA on days 0, 7, 14 and 28. Probing pocket depths (PPD), clinical attachment levels (CAL), bleeding on probing (BOP), gingival index (GI) and plaque index (PI) were measured by a calibrated examiner (TWS) on days 0, 14 and 28. Analysis of covariance was performed using SAS 6.12 and Proc Mixed with group and IL‐1GT as the factors and the baseline levels as the covariate, with output being least squares means and least significant difference (LSD). Significant differences were declared if the p‐value for the F‐statistic was 0.05.

Results: Oral irrigation plus ROH resulted in a significant reduction in PPD, BOP, GI and PI, as well as IL‐β levels by 7 days and PGE2 levels by 14 days, relative to ROH or no oral hygiene. Interestingly, decreased IL‐1β levels in patients using oral irrigation plus ROH was accompanied by a trend for increased levels of the “anti‐inflammatory” cytokine IL‐10. ROH reduced GI, BOP and PI, and PGE2 levels by 14 days, but had no effect on IL‐1β or IL‐10 levels relative to no oral hygiene. The effects of no oral hygiene were reversed by a prophy followed by oral irrigation plus ROH for 14 days. No clinical differences were evident between IL‐1 GT (+) patients (n=11) and GT (−) patients (n=40), but the former had significantly elevated levels of GCF IL‐10 and borderline increases in IL‐1β (p=0.07).

Conclusions: Oral irrigation with water for 14 days had an improved therapeutic benefit for AP over that of routine oral hygiene alone and this improvement was accompanied by a down‐modulation of the pro‐inflammatory cytokine profile in GCF.
Plaque removal by worn toothbrush
Authors: Sforza Nicola Marco , Rimondini Lia , Di Menna Fabrizia , Camorali Chiara
Published: March 2003

Background/aims:

Assessment of the influence of toothbrush wear on plaque (PI) and gingival (GI) indexes.

Method: 20 university students were recruited. PI and GI were recorded at the starting point (T0). Each subject received a toothbrush and toothpaste. 5 measurements of toothbrush were recorded to establish the initial size. The subjects were instructed to brush 3× a day and to refrain from using other plaque removal aids. After 1 month (T1), the subjects were randomly divided into 2 groups: group no. 1 substituted the toothbrush at each monthly visit; group no. 2 brushed only with the toothbrush provided at T0. Recalls were scheduled after 1 (T1), 2 (T2) and 3 months (T3). PI, GI and an index of wear (WI) were calculated using 5 measurements of the toothbrush head and were recorded at recalls.

Results: From T0 to T3, a significant increase of PI was found within both groups. Non‐significant differences, but very close to the significant level (p=0.063), in group no. 1 and significant differences in group no. 2 of GI were found. No significant differences of PI and GI were found between groups. Increase of the WI was registered from T0 to T3 (p<0.001).

Conclusion: Each individual is capable of maintaining low PI, even if using a toothbrush that shows evidence of wear.
Laser Doppler flowmeter measurement of relative gingival and forehead skin blood flow in light and heavy smokers during and after smoking
Authors: Meekin T. N. , Wilson R. F. , Scott D. A. , Ide M. , Palmer R. M.
Published: March 2003

Aim: To determine the effect of the smoking experience on relative blood flow in gingiva and to compare this to skin.

Method: A laser Doppler flowmeter was used to record relative blood flow to healthy gingiva and to forehead skin in smokers and non‐smoking controls. Smoking status was verified by quantitative analysis of serum cotinine. Continuous measurements were made over sequential periods with the subject at rest, during a sham smoking exercise, during smoking of a standard research cigarette (2R1, University of Kentucky) for 5 min and throughout a subsequent recovery period. Non‐smoking controls sham smoked during the equivalent 5 minute smoking period.

Results: No significant differences with respect to the proportional changes of relative gingival blood flow between time points were observed between the groups. However, between‐group comparisons of relative blood flow revealed a significant increase in the relative blood flow to the forehead skin of light smokers (serum cotinine 60 ng/ml; n=6), when compared to heavy smokers (serum cotinine 100 ng/ml; n=9) or to non‐smokers (serum cotinine 10 ng/ml; n=6), 2 min following the smoking experience (p=0.007).

Conclusion: The results do not seem to support the theory that tobacco smoking causes localised vasoconstriction in the periodontal tissues in humans. These data show that smoking causes an acute increase in relative blood flow in forehead skin in light smokers compared to heavy smokers, suggesting a potential induction of tolerance in regular users of tobacco.
Thickness of masticatory mucosa
Authors: Müller Hans‐Peter , Schaller Nils , Eger Thomas , Heinecke Achim
Published: March 2003

Background: The aim of the present study was to assess thickness of all parts of the masticatory mucosa by using an ultrasonic measuring device.

Methods: A total of 40 periodontally healthy subjects, 19 to 30 years old, took part. Thickness of masticatory mucosa was measured at a maximum of 149 sites in each proband.

Results: Female volunteers had significantly thinner mean masticatory mucosa than males (p<0.01). Mean thickness of facial gingiva ranged between 0.7 mm at canines in the maxilla and central incisors in the mandible and 2.3 mm at 3rd molars in the mandible. In the mandible, thickness of lingual gingiva ranged between 0.9 mm at lateral incisors and 2.3 mm at 3rd molars. Interdental gingiva ranged between 1.0 mm 2.1 mm. With 3 mm or more, on average, palatal masticatory mucosa was thickest in the 3rd molar region and at 2nd premolars at more central locations. 2 regions with comparatively thin palatal mucosa of about 2 mm were identified, namely (i) at central and lateral incisors and (ii) at the prominence of the palatal roots of 1st and 2nd molars. The thickest tissue with more than 4 mm, on average, was observed in the tuberosity and retromolar regions.

Conclusions: Considerable intra‐ as well as interindividual variation of thickness of masticatory mucosa could be observed. According to differences in thickness of facial and interdental gingiva, it appears that lining is also an important function of the gingiva in reducing and smoothing the pronounced convexities of the dento‐alveolar, i.e., skeletal, complex.
Effect of triclosan on interferon‐γ production and major histocompatibility complex class II expression in human gingival fibroblasts
Authors: Mustafa Manal , Bakhiet Moiz , Wondimu Biniyam , Modéer Thomas
Published: March 2003

Background, aims: The effect of triclosan (2,4,4′‐trichloro‐2′‐hydroxyl‐diphenyl ether) on the production of interferon‐γ (IFN‐γ) and the expression of major histocompatibility complex (MHC) class II antigen was studied in human gingival fibroblasts isolated from 4 individuals.

Methods/Results:

AII cell lines demonstrated high IFN‐γ production in 24‐h cultures of human gingival fibroblasts stimulated by phytohemagglutinin (PHA) (5 μg/ml). Human gingival fibroblasts showed a high expression of MHC class II when stimulated with 500 and 1000 pg/ml rIFN‐γ in 7‐day cultures. Treatment of the cells with triclosan (0.5 μg/ml) reduced both IFN‐γ production and MHC class II expression in human gingival fibroblast cultures. Similar inhibitory effects on IFN‐γ production and MHC class II expression were observed when the anti‐inflammatory agent dexamethazone (1 μM) was used.

Conclusion: The present study further supports the view that the agent has an anti‐inflammatory effect in addition to its antibacterial capacity.
The use of professional brushing to compare 3 toothbrushes for plaque removal from individuals with gingival recession
Authors: Claydon N. , Leach K. , Newcombe R. G. , Ley F. , Scratcher C. , Addy M.
Published: March 2003

Background: Toothbrush filament configuration now varies considerably, usually with the intention of improving plaque removal overall or from specific sites.

Aims: The aim of the study was to compare 2 branded toothbrushes with a brush designed with a convex filament head arrangement to improve plaque removal from teeth with buccal gingival recession.

Methods: The study was a randomised, 3‐treatment, double‐blind crossover design balanced for residual effects and involving 18 healthy volunteers. On day 1, subjects suspended toothcleaning and returned to the clinic on day 4. Plaque was scored by area and index before and after 2 min of toothbrushing with the allocated brush. Brushing was performed by a hygienist allocating a timed 15 s to each of the 8 buccal and lingual quadrants. 3 days was allowed between treatment periods.

Results: Plaque accumulation differed considerably by site as did plaque removal. Overall plaque removal was 40%. Analysis showed significant subject differences but, no significant period or treatment differences.

Conclusions: Consistent with other reports, it must be concluded that brush design is not a major variable in plaque removal. However using this “robot”‐like model, the dentition of some individuals and specific dental surfaces are inherently more difficult to clean than others.
Bone healing around implants placed in a jaw defect augmented with Bio‐Oss®
Authors: Carmagnola D. , Berglundh T. , Araújo M. , Albrektsson T. , Lindhe J.
Published: March 2003

The present experiment was carried out to study some tissue reactions around implants that were placed in an edentulous ridge which had been augmented with deproteinized natural bovine cancellous bone mineral. In 4 male beagle dogs, the premolars in the right side of the mandible were extracted and a large buccal ridge defect was created by mechanical means. The bone plate at the lingual aspect of the defect was left intact. 5 months later, the distal 2/3 of the defect area was augmented with Bio‐Oss® (Geistlich Sons Ltd, Wolhusen, Switzerland) mixed with a fibrin sealer (Tisseel®, Immuno AG, Vienna, Austria). After 3 months of healing, 3 fixtures (Astra Tech AB, Mölndal, Sweden; TiO‐blast; 8×3.5 mm) were installed in the mandible; 2 were placed in the augmented portion and 1 was placed in the non‐augmented portion of the defect. After a healing period of 3 months, abutment connection was performed and a plaque control period initiated. 4 months later, the dogs were sacrificed and each implant region was dissected. The tissue samples were dehydrated, embedded in plastic, sectioned in the bucco‐lingual plane and examined in the light microscope. It was observed that osseointegration failed to occur to implant surfaces within an alveolar ridge portion previously augmented with Bio‐Oss®. In the augmented portion of the crest, the graft particles were separated from the host tissue as well as from the implant by a well‐defined connective tissue capsule. Although the lingual aspect of all fixtures (test and control) was in contact with hard tissue at the time of installation, after 4 months of function, a deep vertical bone defect frequently had formed at the lingual surface of the implants. It was concluded that in this model (i) Bio‐Oss® failed to integrate with the host bone tissue and (ii) no osseointegration occurred to the implants within the augmented portion of the crest.
Serum antibody titers to Bacteroides forsythus in elderly subjects with gingivitis or periodontitis
Authors: Persson G. Rutger , Schlegel‐Bregenzer Bettina , Chung Whasun O. , Houston Laura , Oswald Teresa , Roberts Marilyn C.
Published: March 2003

Background: The risks for periodontal disease appear to increase with age.

Study purpose:

To determine associations between clinical findings, the presence of specific bacteria in periodontal pockets, and serum antibody titers. 10 older subjects (mean age=73.0 years SD±4.9) with confirmed gingivitis only (gingivitis group) and 10 subjects with periodontitis (mean age: 76.1 years, SD±10.4) (periodontitis group) were studied.

Results: The mean group differences for probing depth and clinical attachment levels were 4.1 mm and 5.6 mm, respectively, and were significantly different (p<0.001). Both groups had high plaque scores (>60% surfaces with plaque). DNA probes demonstrated that B. forsythus was present in 8/10 samples from the periodontitis group and in 7/10 samples from the gingivitis group. The B. forsythus isolates studied were found in four of the subjects with periodontitis and from 2 of the subjects with gingivitis. Serum antibody titers to 6 ribotypes of B. forsythus were studied. Western blots, gradient gels, and pulsed field gel electrophoresis concurrently demonstrated that the B. forsythus isolates were genotypically, and phenotypically unique for each subject. Antibody titers to two selected B. forsythus isolates were significantly higher in the periodontitis group (p<0.01, Mann‐Whitney test). The study confirmed that antibody serum titers to the six different ribotypes of B. forsythus varied greatly between older individuals with gingivitis or periodontitis. Not all strains of B. forsythus elicited higher titers in periodontitis affected subjects.

Conclusions: The results of the present study suggest genotype variation of B. forsythus that is unique to the individual and that serotype variation can be expected. It is possible that B. forsythus under specific host conditions can modulate surface antigen factors to evade the host immune response.
Sulfate‐reducing bacteria in association with human periodontitis
Authors: Langendijk P. S. , Hanssen J. T. J. , Van der Hoeven J. S.
Published: March 2003

Background, aims: Sulfate‐reducing bacteria (SRB) may be etiologically involved in destructive periodontal diseases. These strictly anaerobic bacteria utilize fermentation products for energy conservation by reduction of sulfate to sulfide. This toxic product can accumulate in periodontal pockets in concentrations causing cellular destruction. SRB depend on an actively degrading microbiota to produce a reduced environment, fermentation products and sulfate. The detection frequency of these bacteria is strongly increased in periodontitis compared with healthy sites in the oral cavity.

Method: In this study, the presence of SRB was determined in relation to clinical features of the patients and to site‐specific clinical parameters of periodontitis, such as pocket depth, bleeding and attachment level. Patients with clinical characteristics of severe periodontitis (n=87) were included in the study, 78 were untreated patients and 9 patients were in maintenance care after treatment. Samples were taken (n=261) from the deepest periodontal pockets, and presence of SRB was determined by enrichment culture in an anoxic chamber.

Results: In 64% of the patients, SRB were present in at least 1 pocket. They occurred among patients from 23 to 57 years old, and tended to prevail among patients older than 30 years. There was a tendency to increased SRB occurrence among patients with more than 50% of bleeding sites, or with several angular bony defects or furcations. In 44% of the periodontal pockets SRB were present. They tended to prevail in pockets showing bleeding on probing, furcations, angular bony defects, or an endodontal complication. Presence of SRB was positively correlated with increased pocket depth (p<0.05). SRB were found to be associated with various clinical categories of periodontitis, including early onset periodontitis, rapidly progressive periodontitis, adult periodontitis, and refractory periodontitis. Although SRB predominated among patients with an adult form of periodontitis, i.e., with an occurrence of 72%, there was no significant correlation with age of the patient. Among treated patients under maintenance care, SRB prevalence was significantly reduced in comparison with untreated patients (p<0.02). Occurrence of SRB in periodontal pockets showed an odds ratio of 11.2 in comparison with healthy oral sites.

Conclusion: Periodontal sulfate‐reducing bacteria are associated with several clinical categories of periodontitis and with periodontal sites of increased pocket depth.
A study to assess the plaque inhibitory action of a new zinc citrate toothpaste formulation
Authors: Moran J. , Addy M. , Corry D. , Newcombe R. G. , Haywood J.
Published: March 2003

Background, aims: Zinc‐citrate‐containing toothpastes have previously been suggested to be of value at inhibiting plaque and gingival inflammation. Present formulations have included triclosan which is thought to contribute major antibacterial/antiplaque effects. Alternative antimicrobial agents and other ingredients such as oils could help to produce equally effective formulations. The aim of this study was to determine whether zinc citrate toothpastes containing bromochlorophene and a triglyceride oil (1% and 8%) could inhibit de novo plaque formation.

Methods: Toothpaste slurry rinses were used over a 96‐h period by 24 volunteers, whilst omitting all other oral hygiene procedures. For comparative purposes, a conventional commercial fluoride control toothpaste was also used in this triple cross‐over double blind study.

Results: After 24 and 48 h, there were no statistically significant differences in plaque between the 2 test pastes and the control paste, whether assessed using a plaque index or plaque area. After 96 h, however, a significant reduction in plaque score of 10.6% and 24.2% in plaque area (both p<0.001) was found for the zinc citrate/1% oil toothpaste compared to the control paste. In addition, at 96 h, the 8% oil toothpaste significantly reduced plaque score compared to the control paste by 4.3% (p=0.029).

Conclusions: These findings would appear to warrant further investigation into the potential value of the zinc citrate/bromochlorophene/triglyceride formulation at inhibiting both plaque and gingival inflammation.
Longitudinal periodontal tissue alterations during supportive therapy
Authors: Rosling B. , Serino G. , Hellström M.‐K. , Socransky S. S. , Lindhe J.
Published: March 2003

Aim: The aim of the study was to evaluate disease progression during supportive periodontal therapy in (i) a group of 225 subjects with “normal” (NG) and (ii) a group with high susceptibility (HSG; n=109) to periodontal disease (based on their baseline disease status).

Material and methods: The following variables were recorded at the baseline examination (1 year after they received non‐surgical periodontal therapy) and at the re‐examination after 12 years of maintenance: number of teeth, plaque, probing pocket depth, probing attachment level, bone level in full mouth radiographs. All assessments were performed in a standardized manner and by well‐trained and calibrated examiners. Supportive periodontal therapy was delivered 3–4 × per year and included repeated oral hygiene instruction and debridement. In addition, sites that bled on probing and had a PPD value of 5 mm received subgingival instrumentation.

Results: A comparison between the findings at baseline and after 12 years revealed that in the NG, most subjects maintained their periodontal condition unchanged during the maintenance period; only a few subjects experienced tooth loss and the figures describing the mean amount of bone and attachment loss were small (0.5 mm and 0.3 mm respectively). The HSG patients experienced some tooth loss and also lost significant amounts of bone and attachment during the 12 years of SPT. Thus, in this group of subjects, the mean overall PAL loss amounted to 0.8 mm, i.e., 0.06 mm/tooth surface/year. In the NG, the overall attachment loss was significantly smaller: 0.5 mm, i.e. 0.04 mm/tooth surface/year.

Conclusion: In subjects with a high susceptibility for periodontal disease who had been treated for this condition by non‐surgical means, an SPT program including regularly repeated oral hygiene instruction and subgingival debridement, made it possible to maintain bone and attachment levels at a reasonably stable level over a 12‐year period. A similar SPT provided to a group of subjects with normal susceptibility to periodontal disease, on the other hand, prevented almost entirely major tooth, bone and attachment loss.
Plaque removal with the uninstructed use of electric toothbrushes: comparison with a manual brush and toothpaste slurry
Authors: Renton‐Harper P. , Addy M. , Newcombe R. G.
Published: March 2003

Abstract Background: Individuals purchasing electric toothbrushes for the 1st time will mostly only have the manufacturer’s instructional leaflet for information of usage.

Aims: This study was designed to simulate the 1st‐time purchase and early use of an electric toothbrush with the aim of comparing plaque removal with a manual toothbrush. Secondary aims were to assess chemical plaque removal effects of a toothpaste slurry and to compare between 2 electric brushes which differed only in head speed.

Methods: A group of 16 dentate subjects participated in this single‐examiner blind, randomised, crossover design balanced for residual effects. Subjects had “average” oral hygiene and had never used an electric toothbrush previously. 7 days prior to the study, all subjects received the slower oscillating rotating toothbrush under test to use at home as they wished. The test treatments were brushing with 2 oscillating rotating electric toothbrushes, a manual toothbrush and a rinse with a toothpaste slurry (3 g/10 ml water). On day 1 of each study period, subjects were rendered plaque‐free, suspended oral hygiene and returned on day 5. Plaque was scored at baseline by index and area and after 30 s, 30 s (total 60 s) and 60 s (total 120 s) of the cleaning treatments. Washout periods were at least 2 ½ days.

Results: Highly significant treatment differences were found between the 4 treatments because the toothpaste slurry was totally without effect. Analyses between the 3 brush treatments overall revealed no consistent significant differences. The data suggest that in the early days of electric toothbrush use, subjects perform no better than using a manual brush.

Conclusions: The present study, taken with results from others showing greater benefits from the use of electric brushes, supports the idea that dental professionals should, where possible, provide advice and instruction in the use of such devices.
Marginal bone loss around implants retaining hinging mandibular overdentures, at 4‐, 8‐ and 12‐years follow‐up
Authors: Steenberghe Daniel van , Quirynen Marc , Naert Ignace , Maffei Gaia , Jacobs Reinhilde
Published: March 2003

Aim: The aim of the present study was to study the effect of occlusal factors, oral hygiene, gender and age on the long‐term maintenance of alveolar bone height around screw‐shaped machined surface commercially pure (c.p.) titanium implants retaining hinging mandibular overdentures.

Method: In this retrospective study a long‐term (4‐, 8‐, up to 12‐years) follow‐up of such implant‐retained overdentures was performed. From the population of patients so treated at the University Hospital of the Catholic University Leuven, Department of Periodontology and Department of Prosthetic Dentistry, 158 patients were selected on the basis of being treated before March 1994, and the availability of intra‐oral radiographs (paralleling technique) present at abutment connection (baseline) and at years 4, 8, and 12. For each patient, all relevant clinical data were recorded, and measurements of marginal bone height around the implants were performed on intra‐oral radiographs by means of a digital sliding calliper.

Results: Results indicated that only the factor “time” had a significant influence on marginal bone loss. The age and gender of the patients, dental/prosthetic status in the antagonistic jaw, oral hygiene variables, and location of the implants had no significant effect.

Conclusion: The very high cumulative success rate (97.2%) and limited marginal bone loss (on average 1.7 mm) after 12‐years, encourage this kind of treatment using this type of implants.
Orofacial granulomatosis with gingival onset
Authors: Mignogna Michele D. , Fedele Stefano , Lo Russo Lucio , Lo Muzio Lorenzo
Published: March 2003

Background, aims: Orofacial granulomatosis (OFG) is a descriptive term used for granulomatous disorders of the face and oral cavity that may occur for a variety of reasons, some of which result in significant morbidity and mortality. Although rarely, a granular enlargements of the gingiva may be the first clinical manifestation of OFG, preceding other local or systemic manifestations.

Method: We will report a case of OFG that showed an atypical and monosymptomatic onset with a generalized hyperplastic gingivitis that preceeded other facial and mucosal features by several weeks.

Result:

Considering the variable clinical onset of OFG and its apparent increase in incidence, we emphasize that in some cases, the periodontologist, as first consulted health care professional, plays an important role to detect this disorder. Early diagnosis of OFG is a crucial step to prevent and cure its unsightly sequelae and sometimes avoid progression of systemic potentially life‐threatening OFG‐related diseases.

Conclusion: Thus, when none of the common causes of gingival enlargement can be detected, OFG diagnosis should be suspected.
On the symmetry of periodontal disease
Authors: Mombelli Andrea , Meier Claudia
Published: March 2003

Background, aim: Symmetry is a common feature of biological systems, and can be observed in multiple aspects of the human body. The purpose of this study was to estimate the impact of symmetry on variance observed in intraoral topographic distribution patterns of chronic periodontitis.

Method: This analysis was performed on a data set from 56 subjects, including clinical and microbiological variables, recorded at the mesial and distal aspect of every tooth in the entire dentition. The impact of contralateral conditions was determined on the level of the site, the tooth, and the quadrant.

Results: Significant correlations were detected between probing depths, recession, attachment levels, total cultivable bacterial counts and the plaque index recorded on the right and left side on all levels of analysis. The odds for bleeding on sampling, as well as for the presence of P. intermedia/nigrescens and A. actinomycetemcomitans increased significantly if the respective contralateral site was positive for the same parameter. In combining ipsilateral and contralateral parameters into the analysis it could be shown in several instances that this contralateral effect was stronger than the impact of other, ipsilateral factors. As an example, the odds for bleeding on sampling increased up to 10 fold if the contralateral site was bleeding, whereas the ipsilateral total cultivable count, determined at the same site, explained less than 30% of the variation in the bleeding tendency.

Conclusion: These findings support the view that the development of periodontal disease in any site cannot be explained by the influence of local detrimental factors alone.
Utilisation of locally delivered doxycycline in non‐surgical treatment of chronic periodontitis
Authors: Wennström Jan L. , Newman Hubert N. , MacNeill Simon R. , Killoy William J. , Griffiths Gareth S. , Gillam David G. , Krok Lena , Needleman Ian G. , Weiss Gina , Garrett Steven
Published: March 2003

Aim: In the present 6‐month multicentre trial, the outcome of 2 different approaches to non‐surgical treatment of chronic periodontitis, both involving the use of a locally delivered controlled‐release doxycycline, was evaluated.

Material and methods: 105 adult patients with moderately advanced chronic periodontitis from 3 centres participated in the trial. Each patient had to present with at least 8 periodontal sites in 2 jaw quadrants with a probing pocket depth (PPD) of 5 mm and bleeding following pocket probing (BoP), out of which at least 2 sites had to be 7 mm and a further 2 sites 6 mm. Following a baseline examination, including assessments of plaque, PPD, clinical attachment level (CAL) and BoP, careful instruction in oral hygiene was given. The patients were then randomly assigned to one of two treatment groups: scaling/root planing (SRP) with local analgesia or debridement (supra‐ and subgingival ultrasonic instrumentation without analgesia). The “SRP” group received a single episode of full‐mouth supra‐/subgingival scaling and root planing under local analgesia. In addition, at a 3‐month recall visit, a full‐mouth supra‐/subgingival debridement using ultrasonic instrumentation was provided. This was followed by subgingival application of an 8.5% w/w doxycycline polymer at sites with a remaining PPD of 5 mm. The patients of the “debridement” group were initially subjected to a 45‐minute full‐mouth debridement with the use of an ultrasonic instrument and without administration of local analgesia, and followed by application of doxycycline in sites with a PPD of 5 mm. At month 3, sites with a remaining PPD of 5 mm were subjected to scaling and root planing. Clinical re‐examinations were performed at 3 and 6 months.

Results: At 3 months, the proportion of sites showing PPD of 4 mm was significantly higher in the “debridement” group than in the “SRP” group (58% versus 50%; p<0.05). The CAL gain at 3 months amounted to 0.8 mm in the “debridement” group and 0.5 mm in the “SRP” group (p=0.064). The proportion of sites demonstrating a clinically significant CAL gain (2 mm) was higher in the “debridement” group than in the “SRP” group (38% versus 30%; p<0.05). At the 6‐month examination, no statistically significant differences in PPD or CAL were found between the two treatment groups. BoP was significantly lower for the “debridement” group than for the “SRP” group (p<0.001) both at 3‐ and 6 months. The mean total treatment time (baseline and 3‐month) for the “SRP” patients was 3:11 h, compared to 2:00 h for the patients in the “debridement” group (p<0.001).

Conclusion: The results indicate that simplified subgingival instrumentation combined with local application of doxycycline in deep periodontal sites can be considered as a justified approach for non‐surgical treatment of chronic periodontitis.
Effect of nicotine‐treated epithelial cells on the proliferation and collagen production of gingival fibroblasts
Authors: Giannopoulou Catherine , Roehrich Nicolas , Mombelli Andrea
Published: March 2003

Background, aims: Several in vitro and in vivo studies have indicated that tobacco smoking may be an important risk factor for the development and severity of inflammatory periodontal disease.

Method: In the present study, we developed an in vitro model to study the interactions between nicotine‐treated epithelial cells (EC) and gingival fibroblasts (GF) derived from the same patient. EC were treated with nicotine concentrations varying from 1 μg/ml to 500 μg/ml and their effect on different functions of GF was studied. The proliferation of GF was evaluated by the incorporation of 3H‐thymidine. A dose‐dependent inhibition was observed with nicotine concentrations 100 μg/ml. Similar results were observed when studying the total protein synthesis of GF by incorporation of 3H‐proline into non‐dialyzable material.

Results: When collagen production was evaluated by 3H‐proline incorporation into collagenase‐sensitive protein, a dose‐dependent reduction was observed: the degree of inhibition varied from 25% with 50 μg/ml nicotine, to almost 60% with 500 μg/ml. Interestingly, the production of non‐collagenous proteins decreased by almost 50% only when EC were treated with the highest concentration of nicotine.

Conclusions: The results suggest that epithelial cells, acting as mechanical barrier, can reduce but not completely eliminate the deleterious effect of nicotine on gingival fibroblasts.
Granulocyte elastase, matrix metalloproteinase‐8 and prostaglandin E2 in gingival crevicular fluid in matched clinical sites in smokers and non‐smokers with persistent periodontitis
Authors: Söder B. , Jin L. J. , Wickholm S.
Published: March 2003

Background/aims: Smokers with persistent periodontitis may have granulocytes with impaired function. This study aimed to determine the levels of granulocyte elastase, matrix metalloproteinase‐8 (MMP‐8) and prostaglandin E2 (PGE2) in gingival crevicular fluid (GCF) in smokers and non‐smokers with persistent periodontitis.

Methods: We analyzed GCF from 70 matched sites in 29 periodontitis and 6 gingivitis sites in 34 subjects, 17 smokers, and 17 non‐smokers. We also analyzed separately GCF from 28 of these subjects, 14 smokers and 14 non‐smokers in 14 matched periodontitis sites. The following measurements were made: elastase complexed to α1‐antitrypsin (EA‐α1AT) and MMP‐8 with ELISA, functional elastase with a chromogenic substrate, and PGE2 with radioimmunoassay (125I RIA). The significance of the findings was determined with Mann‐Whitney test.

Results: In the 29 matched periodontitis sites, smokers had significantly more functional elastase (p<0.005) and more EA‐α1AT (p<0.05) than non‐smokers. In the 14 matched periodontitis sites in 14 smokers and 14 non‐smokers, the former had significantly more functional elastase than the latter (p<0.001). A significant correlation was found between EA‐α1AT and MMP‐8 in smokers (p<0.05) and non‐smokers (p<0.001) and a positive correlation between levels of functional elastase and MMP‐8 in non‐smokers (r2=0.98; p<0.001).

Conclusions: Granulocyte function seems to be impaired in smokers with persistent periodontitis. The cells react to the bacterial challenge by releasing serine proteases, which reflect the degradation of connective tissue. The risk of progression of the disease is therefore higher in smokers with persistent periodontitis than in non‐smokers.