bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative evaluation of casting retention using the ITI solid abutment with six cements
Authors: Mansour Ahmed , Ercoli Carlo , Graser Gerald , Tallents Ross , Moss Mark 
Published: March 2003

Abstract: Objective: The purpose of this study was to test the retention of metal copings fabricated to fit on the one‐groove, one flat‐sided solid titanium abutment using six different cements. Materials and methods: Ten hollow screw 3.8 mm ITI implants were mounted in acrylic resin blocks. A solid titanium abutment was placed on each implant and torqued at 35 Ncm. Prefabricated burn‐out caps were placed on the titanium abutment and wax loops added to the occlusal surface to allow for subsequent retention testing. All plastic caps were embedded in phosphate‐bonded investment and cast with noble alloy. Castings were inspected for surface irregularities using a stereomicroscope at 10× magnification.The six cements were: 1) eugenol‐free zinc oxide (Temp Bond NE); 2) zinc‐oxide eugenol (IRM); 3) zinc phosphate (Hy‐Bond); 4) resin‐modified glass ionomer (Protec Cem); 5) zinc polycarboxylate (Durelon) and 6) 10‐methacryloyloxydecyl dihydrogen phosphate resin (Panavia 21). After cementation, implant–abutment–casting assemblies were stored for 24 h in 100% humidity. Samples were subjected to a pull‐out test using an Instron universal testing machine at a crosshead speed of 0.5 mm/min. The load required to de‐cement each coping was recorded and mean values for each group calculated. Means and standard deviations of loads at failure were analyzed using ANOVA and a Tukey studentized test. Statistical significance was set at P ≤ 0.05. Results: The mean values (± SD) of loads in kilograms at failure (n = 10) for the various cements were as follows: Temp Bond 3.18 (± 1.1) (Tukey group D), IRM 9.25 (± 3.83) (Tukey group CD), HY‐Bond 10.9 (± 6.52) (Tukey group C), Protec Cem 18.98 (± 6.23) (Tukey group B), Durelon 23.55 (± 4.29) (Tukey group B) and Panavia 21, 36.53 (± 8.1) (Tukey group A). Means with the same letter in the Tukey grouping are not significantly different. Conclusions: The retention values of castings cemented to ITI solid abutments have not been reported in the literature. Within the limitations of this in vitro study, the results do not suggest that one cement type is better than another, but they do provide a ranking order of the cements in their ability to retain the castings. This ranking is somehow different than that obtained when the same cements are used on natural teeth. The material and surface characteristics of the implant abutment are likely responsible for this difference. Cement retention values obtained from studies that use teeth as abutments may be misleading when used in cement‐retained implant‐supported crowns. It is at the clinician's discretion to use a certain type of cement, based on the situation at hand.
Three‐dimensional finite element analysis of implant stability in the atrophic posterior maxilla
Authors: Tepper Gabor , Haas Robert , Zechner Werner , Krach Wolfgang , Watzek Georg 
Published: March 2003

Abstract: Sinus lifting is performed with a variety of materials and techniques without a precise knowledge of the quantity of augmentation. This study based on three‐dimensional finite element analysis was designed to show which surgical procedure and which amount of peri‐implant packing yields the best bony support for dental implants. Eight 3D‐FE models were used. Four modeled standard situations simulated quantitatively different packing situations produced by differences in surgical approach: i. no packing; ii. thin 1 mm bony sheath; iii. oblique subcomplete packing; iv. complete bony peri‐implant packing up to the implant end. A fifth model compared a standard implant with a length of 13.5 mm and a diameter of 3.75 mm with a 7‐mm‐long and 5‐mm‐thick implant. In three additional models the stress response of the bone–implant system was evaluated in the absence of a cortical layer, thus simulating an extreme degree of maxillary atrophy. In all models the modeled implants were loaded at their points of emergence with an assumed force of 100 N. The vector of the loading force was inclined 30° posteriorly relative to the implant axis and 30° away from the sagittal plane. The bone–implant interface was assumed to be perfect simulating full osseointegration.The final evaluation of the FE models showed complete peri‐implant packing to reduce displacements of the implant tip by 32% vs. no sheathing/packing. Van Mises' equivalent stresses were used to assess the stresses in both human bone and titanium alloy implants. The highest stress levels in bone were predicted for the case without sufficient implant sheathing. In the models with adequate bony implant support, intrabony stresses were generally reduced by up to − 40%. The structural stiffness of the bone–implant system increased with the extent of sinus floor elevation. The results indicate that more extensive peri‐implant packing reduces implant displacement, intrabony stresses and stresses at the bone–implant interface.
Community periodontal index of treatment needs and prevalence of periodontal conditions
Authors: Benigeri Mike , Brodeur Jean‐Marc , Payette Martin , Charbonneau Anne , Ismaïl Amid I. 
Published: March 2003

AbstractBackground/aims: In 1977, the World Health Organization (WHO) proposed a new index, the community periodontal index of treatment needs (CPITN) to evaluate the periodontal treatment needs of populations. The aim of this study is to compare different approaches of recording and presenting the CPITN.Methods: A sample of 2110 subjects aged 35–44 years were examined between September 1994 and July 1995, throughout the province of Quebec, Canada. For each tooth (3rd molars excluded), the presence of bleeding and calculus, the level of epithelial attachment, and the depth of periodontal pockets were measured. Periodontal pocket depths were measured from the edge of the free gingiva, at 2 sites (mesiovestibular and vestibular), as well as all around the tooth.Results: Only 8.5% of adults had at least one tooth with a 6 mm or deeper periodontal pocket when probing on 2 sites, whereas if probing is done all around the tooth, this percentageis 2.5× higher (21.4%). The partial recording of pocket depths (10 index teeth recommended by WHO, or 2 quadrants chosen at random) resulted in an underestimation of the prevalence of subjects with at least one tooth with a periodontal pocket (CPITN score 3 and 4). Among subjects with at least one tooth with a 6 mm or deeper periodontal pocket, 12% were not detected with the 10 index teeth recording, and 25% go undetected with the measure on 2 quadrants. Finally, using the % of subjects with periodontal pockets overestimates the prevalence of deep pockets compared with using sextants. Indeed, close to 30.0% of sextants have no treatment needs, whereas only 5.2% of subjects are in this category. Similarly, 7.7% of sextants have at least one tooth with a 6 mm or deeper periodontal pocket, yet there are 3× more subjects in this category (21.4%).
The periodontal abscess (II). Short‐term clinical and microbiological efficacy of 2 systemic antibiotic regimes *
Authors: Herrera David , Roldán Silvia , O'Connor Ana , Sanz Mariano 
Published: March 2003

Background/aims: The aim of this short‐term open parallel longitudinal clinical study was to compare the clinical and microbiological efficacy of 2 different antibiotic regimes in the treatment of acute periodontal abscesses.Method: After patient selection, a clinical examination was carried out recording the following variables: pain, edema, redness, swelling, bleeding on probing, suppuration, tooth mobility, lymphadenopathy, and probing pocket depth. Microbiological samples were taken from the lesion and the patient was randomly assigned to one of two antibiotic regimes: azithromycin or amoxicillin/clavulanate. Clinical variables were recorded, and microbiological samples were taken, at 3–5 days, 10–12 days and 30 days. Additional mechanical treatment (debridement and scaling) was performed in the third visit (10–12 days). Blood and urine samples were collected at baseline and after 10–12 days. Microbiological samples were processed by anaerobic culturing, and isolated periodontal pathogens were tested for antibiotic susceptibility by means of the spiral gradient endpoint methodology.Results: 15 patients took azithromycin, and 14 amoxicillin/clavulanate. Subjective clinical variables demonstrated statistically significant improvements with both antibiotic regimes, which lasted for at least 1 month (p<0.01). Objective clinical variables also showed clear improvements, being statistically significant after 30 days with probing pocket depth in the azithromycin group (p<0.01). Microbiologically, short‐term reductions were detected with both antibiotics, however fast recolonization occurred after the third visit. No significant differences were found between both treatment regimes. Antibiotic susceptibilities demonstrated no resistances for amoxicillin/clavulanate, while 2–3 strains of each studied pathogen were resistant to azithromycin.Conclusions: However, both antibiotic regimes were effective in the short‐term treatment of periodontal abscesses in periodontitis patients.
Chlorhexidine spray versus chlorhexidine mouthwash in the control of dental plaque after periodontal surgery
Authors: Francetti Luca , Del Fabbro Massimo , Testori Tiziano , Weinstein Roberto L. 
Published: March 2003

Background/aims: This clinical trial aimed at comparing 2 different means of delivering chlorhexidine digluconate (CHX) in the oral hygiene phase during the 2 weeks following periodontal surgery.Method: 40 patients were randomly divided into 2 groups: A (using CHX mouthwash) and B (using CHX spray). Professional oral hygiene was carried out immediately before surgical operation. For 7 days after surgery, group A used CHX mouthwash and group B CHX spray on the teeth involved in the surgical procedure, while mechanical oral hygiene was maintained only on the teeth not involved surgically. After suture removal, on the 7th day, patients were allowed to perform mechanical oral hygiene also on surgical sites. Plaque index (PI) and stain index (SI) were evaluated on the 7th and 14th days after the operation.Results: In both groups, PI increased similarly with respect to the baseline in surgically involved teeth, being 0.25±0.41 (SD) and 0.15±0.26, respectively, in A and B, on day 7, and 0.14±0.23 (A) and 0.10±0.22 (B), on day 14. There was no significant difference between A and B on either day 7 or 14. On the contrary, SI increased significantly in respect to the baseline over the 14 days in group A at both involved and not involved sites, while it did not differ from the baseline in group B.Conclusions: The present results indicate that the efficacy of CHX spray in the post‐surgical control of dental plaque is not different from that of CHX mouthwash. Tooth staining, on the contrary, was significantly lower in the group using CHX spray. The observed effects might be related to the way of delivering CHX and to the total dose administered, about 80% lower in group B in respect to A. Further studies are needed to validate the preliminary findings of the present study.
PCR monitoring for tetracycline resistance genes in subgingival plaque following site‐specific periodontal therapy
Authors: Manch‐Citron Jean N. , Lopez Gilbert H. , Dey Anjana , Rapley John W. , MacNeill Simon R. , Cobb Charles M. 
Published: March 2003

Background: The selection of antibiotic resistance genes during antibiotic therapy is a critical problem complicated by the transmission of resistance genes to previously sensitive strains via conjugative plasmids and transposons and by the transfer of resistance genes between gram‐positive and gram‐negative bacteria. The purpose of this investigation was to monitor the presence of selected tetracycline resistance genes in subgingival plaque during site specific tetracycline fiber therapy in 10 patients with adult periodontitis.Method: The polymerase chain reaction (PCR) was used in separate tests for the presence of 3 tetracycline resistance genes (tetM, tetO and tetQ) in DNA purified from subgingival plaque samples. Samples were collected at baseline, i.e., immediately prior to treatment, and at 2 weeks, and 1, 3, and 6 months post‐fiber placement. The baseline and 6‐month samples were also subjected to DNA hybridization tests for the presence of 8 putative periodontal pathogenic bacteria.Results: PCR analysis for the tetM resistance gene showed little or no change in 5 patients and a decrease in detectability in the remaining 5 patients over the 6 months following tetracycline fiber placement. The results for tetO and tetQ were variable showing either no change in detectability from baseline through the 6‐month sampling interval or a slight increase in detectability over time in 4 of the 10 patients. DNA hybridization analysis showed reductions to unmeasurable levels of the putative periodontal pathogenic bacteria in all but 2 of the 10 patients.Conclusions: These results complement earlier studies of tet resistance and demonstrate the efficacy of PCR monitoring for the appearance of specific resistance genes during and after antibiotic therapy.
Changes in substance P and neurokinin A in gingival crevicular fluid in response to periodontal treatment
Authors: Lundy Fionnuala T. , Mullally Brian H. , Burden Donald J. , Lamey Philip‐John , Shaw Christopher , Linden Gerard J. 
Published: March 2003

AbstractBackground: The study of periodontitis provides a unique model for assessing the involvement of neuropeptides in inflammatory disease.Aim: To investigate the effects of periodontal treatment, resulting in a return to periodontal health, on the levels of substance P (SP) and neurokinin A (NKA) in gingival crevicular fluid (GCF).Method: We completed a cause of non‐surgical treatment for 8 subjects with periodontitis (6 females 2 males, mean age 45.1, range 38–67 years) started a course of non‐surgical periodontal treatment. Clinical indices were measured at 2 periodontitis sites at the initial visit and at 8 weeks after the completion of treatment in each subject. A 30‐s sample of GCF was collected from each test site using perio paper strips. Each strip was placed into 500 μl of ice cold 0.1M PBS, pH 7.4, vortex mixed for 30 s, and then stored at −70°C until analysed by radioimmunoassay.Results: The clinical condition of all test sites improved as a result of the periodontal treatment. The levels (pg/30 s sample) of SP fell from 56.3 (SD 66.0) at the initial visit to 4.2 (3.1) after treatment, p=0.017. The concentration (pg/μl) of SP in GCF fell from 140.6 (175.6) to 24.2 (11.1), p=0.036. The levels of NKA fell from 30.5 (17.1) to 10.6 (4.9), p=0.012 whereas the concentration changed little from 85.4 (43.5) to 61.6 (15.1), p=0.41.Conclusion: The reduction in inflammation resulting from effective periodontal treatment is associated with a reduction in the levels of tachykinins in gingival crevicular fluid.
Testing the efficacy of plaque removal of a prototype brush head for a powered toothbrush
Authors: McCracken G. I. , Heasman L. , Stacey F. , Kelly P. J. , Heasman P. A. 
Published: March 2003

AbstractBackground/aims: The principal aim of the study was to compare the efficacy of a powered toothbrush (PTB) prototype (B) brush head in removing dental plaque to the relative efficacy of a marketed model (A).Method: A 12‐week, 2‐group, 2‐treatment, double‐blind trial of 2, two‐brush heads (with the same power unit) recruited 62 volunteers (18–25 years) who were non‐clinical university students. After a screening visit, 31 subjects were allocated to each of groups A and B at baseline with stratification according to gender and plaque index. After 48 h of plaque growth, subjects underwent a timed and supervised brushing episode with the allocated PTB (visit 1). Subjects then used the PTBs at home for 12 days before being recalled (visit 2) and asked again to abstain from all oral hygiene measures for 48 h. Supervised brushing was repeated (visit 3) before the subjects were dismissed for a further 10‐week, unsupervised period of home use of the PTBs. The sequence of visits (2 and 3) was then repeated at visits 4 and 5.Results: The sole outcome variable was plaque which was scored at all visits using the modified Quigley & Hein Index (PI) at full mouth (FM), interproximal (IP) and smooth surfaces (S). At visits 1, 3 and 5, the PI was recorded both before and after supervised brushing. There were no significant differences in PI between the brushing groups at baseline, visit 1, visit 2 or visit 5 (2 sided t‐test). At visit 3, the prototype achieved significantly lower PIs than the marketed PTB brush head for IP (and FM) surfaces, this difference was most apparent on posterior tooth surfaces. For within‐group changes, PIs at visit 2 were significantly lower than those at baseline (paired t‐test), an observation which may be attributable to the improved cleaning and ‘novelty effect’ of a PTB. The PIs at visit 5 were significantly higher than the baseline values (paired t test) and this may be accountable to an element of Hawthorne effect and/or, a fall off in compliance over the entire 12 weeks.Conclusion: We conclude that this in vivo model is appropriate for testing the efficacy of PTB prototypes but only over a 2‐week period, as the inter‐group differences were not maintained over the full 12 weeks of the trial.
Prevalence of Bacteroides forsythus, Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in subgingival microflora of Japanese patients with adult and rapidly progressive periodontitis
Authors: Yano‐Higuchi Kazuko , Takamatsu Nobuhiro , He Tao , Umeda Makoto , Ishikawa Isao 
Published: March 2003

AbstractBackground, aims: This study investigated the prevalence of Bacteroides forsythus, Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans among various periodontitis patients and healthy individuals in Japan, and correlated it with clinical parameters.Method: Subgingival plaque samples were collected from 21 patients with adult periodontitis (AP), 8 with rapidly progressive periodontitis (RPP) and 15 healthy individuals.Results: The frequency detected in culture was as follows: B. forsythus was found in 47.6% of AP sites and in 37.5% of RPP sites. P. gingivalis was identified in 64.3% of AP and 59.4% of RPP sites. A. actinomycetemcomitans was detected in 4.8% of AP and 3.1% of RPP sites. The 3 species were detected in only 2 of the healthy individuals. The proportion of B. forsythus in the total microflora in culture was 0.07% in the healthy group, 4.1% in AP and 2.4% in RPP. The proportions of P. gingivalis were 0% in the healthy group, 18.8% in AP and 16.2% in RPP. The proportion of A. actinomycetemcomitans was very low in all 3 groups. A DNA probe detected B. forsythus in 78.6% of AP and 65.6% of RPP sites, as well as P.gingivalis in 58.3% of AP and 59.4% of RPP sites. A. actinomycetemcomitans was detected in only 1.2% of AP sites. The 3 species were undetectable in the healthy group.Conclusions: The prevalence and the proportion of B. forsythus and P. gingivalis were significantly correlated with clinical parameters, suggesting that B. forsythus and P. gingivalis are closely related to AP and RPP in the Japanese population.
The association of cigarette smoking with alveolar bone loss in postmenopausal females
Authors: Payne Jeffrey B. , Reinhardt Richard A. , Nummikoski Pirkka V. , Dunning David G. , Patil Kashinath D. 
Published: March 2003

AbstractBackground, aims: The purpose of this 2‐year longitudinal clinical study was to determine the impact of smoking on alveolar bone height and density changes in postmenopausal females.Methods: 59 postmenopausal women completed this study, including 38 non‐smokers and 21 smokers. All subjects had a history of periodontitis, participated in 3‐ to 4‐month periodontal maintenance programs and were within 5 years of menopause at the study outset. 4 vertical bite‐wing radiographs of posterior sextants were taken at baseline and 2‐year visits. Radiographs were evaluated using computer‐assisted densitometric image analysis (CADIA); changes in interproximal alveolar bone density and changes in alveolar bone height were determined. Relative clinical attachment levels (RCAL) and presence/absence of plaque and bleeding on probing were recorded.Results: Smokers exhibited a higher frequency of alveolar bone height loss (p< 0.05) and crestal (p<0.03) and subcrestal (p<0.02) density loss relative to non‐smokers. Smokers exhibited a trend (p<0.08) toward a higher frequency of 2.0 mm RCAL loss over the 2‐year period. Plaque and bleeding on probing did not differ between smokers and non‐smokers. A significant interaction, determined by repeated measures ANOVA, was noted between systemic bone mineral density (BMD) at the lumbar spine and smoking on alveolar bone density change (p<0.05). Only non‐smoking patients with normal BMD realized a mean net gain in alveolar bone density; osteoporotic/osteopenic subjects (n=25) and smokers lost alveolar bone density.Conclusion: Postmenopausal female smokers were more likely to lose alveolar bone height and density than non‐smokers with a similar periodontitis, plaque and gingival bleeding experience. In addition, both smoking and osteoporosis/osteopenia provided a negative influence on alveolar bone.
Cytokine, elastase and oxygen radical release by Fusobacterium nucleatum‐activated leukocytes: a possible pathogenic factor in periodontitis
Authors: Sheikhi M. , Gustafsson A. , Jarstrand C. 
Published: March 2003

AbstractPeriodontitis is characterised by tissue destruction caused by reactive oxygen species (ROS) and proteolytic enzymes, which are released by the interaction between bacteria and phagocytes. We estimated the ability of Fusobacterium species to induce release of tissue destructive and proinflammatory mediators from in vitro activated peripheral leukocytes. ROS was measured with the nitroblue tetrazolium (NBT) method, elastase with a specific chromogenic substrate and cytokines, including interleukin 1β (IL‐1β), tumour necrosis factor α (TNF‐α), and interleukin 8 (IL‐8) with a sandwich ELISA method. Various clinical isolates of unopsonized Fusobacterium species stimulated the neutrophils to an increased NBT‐ reduction. IL‐1β, TNFα, IL‐8 and elastase were released in significantly higher levels from neutrophils stimulated by Fusobacterium species. In conclusion, unopsonized Fusobacterium species can induce increased production of oxygen radicals, cytokines and elastase from leukocytes activated in vitro.
Detection of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in dental plaque samples from children 2 to 12 years of age
Authors: Okada Mitsugi , Hayashi Fumiko , Nagasaka Nobuo 
Published: March 2003

AbstractThe purpose of this study was to detect the presence of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in plaque samples from 104 children, collected from their toothbrushes using a polymerase chain reaction (PCR). The age range of all subjects was 2–12 years. 21, 73 and 10 children with healthy gingiva, gingivitis and periodontitis respectively were selected. Plaque samples were collected from all erupted teeth sites using a sterile toothbrush. The mean concentration of DNA recovered from brushing plaque samples was approximately 660 μg/ml, which was sufficient for performing a PCR‐based survey. Both A. actinomycetemcomitans and P. gingivalis were detected in the primary and mixed dentition. The prevalence of A. actinomycetemcomitans in healthy subjects was 4.8%, and those with gingivitis and periodontitis was 6.8% and 20.0% respectively, while the prevalence of P. gingivalis was 4.8% in healthy subjects, and 9.6% and 20.0% in those with gingivitis and periodontitis, respectively. Our survey, using a toothbrush, indicated that A. actinomycetemcomitans and P. gingivalis are rarely present in oral cavities of healthy children.