bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of the Interimplant Distance on Crestal Bone Resorption and Bone Density: A Histomorphometric Study in Dogs
Authors: Papalexiou Vula , Novaes Arthur B. , Ribeiro Ricardo F. , Muglia Valdir , Oliveira Rafael R. 
Published: April 2006

Background: The position of gingival soft tissues depends on the position and health of the underlying alveolar bone. The aim of this study was to evaluate the influence of different interimplant distances on crestal bone resorption after prosthetic restoration with a 5‐mm distance between the contact point and the bone crest.Methods: The mandibular bilateral premolars of six dogs were extracted and, after 12 weeks, each dog received eight implants, totaling 48 implants in the experiment. Two pairs, one in each hemiarch, were separated by 2 mm (group 1) and two by 3 mm (group 2). After 12 weeks, the implants received temporary acrylic prostheses. After 4 more weeks, metallic crowns substituted the temporary prostheses. After 4 more weeks, the animals were sacrificed, and their hemimandibles were removed, dissected, and processed.Results: For groups 1 and 2, respectively, the mean of interimplant bone resorption (IIBR) analyzed histologically was 2.03 and 1.98 mm (P ≥0.05), and the mean of the distal extension bone resorption was 2.04 and 1.92 mm for groups 1 and 2, respectively (P ≥0.05). The crestal bone resorption between the implants was 0.13 mm (P ≥0.05) for both groups. The mean of IIBD for groups 1 and 2 was 79% and 80%, respectively. When the IIBD was compared to the distal extension bone density for group 1 (79% and 64%) and group 2 (80% and 62%), statistically significant differences were obtained for both groups (P ≤0.05).Conclusions: The distances of 2 and 3 mm between implants do not result in statistically significant differences in crestal bone resorption around implant surfaces in dogs. The bone density is enhanced when loading is present at the interimplant area.
Oral Post‐Surgical Complications Following the Administration of Bisphosphonates Given for Osteopenia Related to Malignancy
Authors: Soileau Kristi M. 
Published: April 2006

Background: This case report seeks to illustrate the clinical consequences of the administration of bisphosphonate therapy to prevent osteopenia secondary to malignancy in one patient.Methods: A 69‐year‐old white female with a history of breast cancer with metastasis presented with pain in the upper left quadrant and periodontal pocketing of at least 6 mm in each of the four quadrants of the oral cavity. One week following surgery on the lower right region, lingual bone exposure was noted, and several attempts at achieving healing over the course of 15 months proved unsuccessful.Results: Upon referral to a surgeon at the Louisiana State University Medical Center, New Orleans, Louisiana, a potential causative factor was finally identified. The drug zoledronic acid, a bisphosphonate given for prevention of osteoclastic activity of bone metastasis, secondary to breast cancer, was identified as the possible cause of inhibition of healing, most likely from regional vascular insufficiency. The drug was immediately discontinued. The patient is healing very slowly with the aid of hyperbaric therapy; she has been unable to achieve smoking cessation, which is deterring thorough healing of the exposed bony area on the lower right lingual side.Conclusions: Physicians and dentists alike must become increasingly aware of impaired oral healing following the use of bisphosphonates given for malignancy‐related osteopenia. A dental exam should be performed before bisphosphonate therapy, as recommended for radiation therapy related to malignancy.
Effect of Cigarette Smoke Inhalation and Estrogen Deficiency on Bone Healing Around Titanium Implants: A Histometric Study in Rats
Authors: Carvalho Marcelo Diniz , Benatti Bruno Braga , César‐Neto João Batista , Nociti Francisco Humberto , da Rocha Nogueira Filho Getúlio , Casati Marcio Zaffalon , Sallum Enilson Antonio 
Published: April 2006

Background: It has been shown that cigarette smoke inhalation (CSI) and estrogen deficiency (OVX) may affect bone quality around titanium implants; however, their association has not been evaluated. Therefore, this study aimed to verify the effects of CSI associated with OVX on bone healing around titanium implants.Methods: The tibia surface of 45 female Wistar rats was surgically exposed, and screw‐shaped titanium implants were placed. The animals were randomly assigned to OVX (ovariectomized rats; n = 15), SHAM (sham‐operated rats; n = 15), and CSI + OVX (4 months of intermittent cigarette smoke inhalation, starting 2 months before implant placement in ovariectomized rats; n = 15). The implants were placed at the time of OVX or SHAM surgery. After 60 days, the animals were sacrificed and undecalcified sections obtained. The percentages of mineralized tissue (bone density [BD]) in a 500‐μm‐wide zone lateral to the implant, bone filling (BF) within the limits of the threads, and bone‐to‐implant contact (BIC) were measured in cortical (zone A) and cancellous (zone B) bone.Results: In zone A, the CSI + OVX group showed a significant difference regarding BIC and BD (P <0.05) compared to the other groups. In zone B, data analysis showed that the CSI + OVX group presented the lowest percentage of BD and BIC, followed by the OVX and SHAM groups, respectively (P <0.05).Conclusion: Within the limits of the present study, it can be concluded that cigarette smoke inhalation amplified the deleterious effects of estrogen deficiency, affecting both preexisting and newly formed bone in the cortical and cancellous bone around titanium implants.
Periodontal Disease in Patients From the Original Kostmann Family With Severe Congenital Neutropenia
Authors: Carlsson Göran , Wahlin Ylva‐Britt , Johansson Anders , Olsson Anders , Eriksson Torbjörn , Claesson Rolf , Hänström Lennart , Henter Jan‐Inge 
Published: April 2006

Background: Patients with Kostmann syndrome (severe congenital neutropenia [SCN]) typically normalize their absolute neutrophil count (ANC) upon granulocyte colony‐stimulating factor (G‐CSF) therapy. However, although they no longer experience life‐threatening bacterial infections, they frequently still have recurrent gingivitis and even severe periodontitis, often starting in early childhood.Methods: We studied the periodontal disease in the four surviving patients belonging to the family originally described by Kostmann. Their odontological records, x‐rays, color photos, bacterial cultures, serum antibodies to oral bacteria, and histopathological examinations were reviewed. The data were also correlated to previous investigations on their antibacterial peptides and molecular biology.Results: Three patients had periodontal disease, despite normal ANC and professional dental care, and had neutrophils deficient in antibacterial peptides. One of these patients also had a heterozygous mutation in the neutrophil elastase gene, had severe periodontal disease and overgrowth of the periodontal pathogen Actinobacillus actinomycetemcomitans in the dental flora, and 15 permanent teeth had been extracted by the age of 27. One bone marrow–transplanted patient had no periodontal disease.Conclusions: Normalized ANC levels are not sufficient to maintain normal oral health in SCN patients, and because neutrophils are important for first‐line defense and innate immunity, the deficiency of the antibacterial peptide LL‐37 probably explains their chronic periodontal disease. Professional dental care is still important for SCN patients, despite treatment with G‐CSF and normal ANC levels. Whether antibacterial peptides play a role in the pathogenesis of periodontitis in other patients remains to be elucidated.
Surgical or Non‐Surgical Periodontal Treatment: Factors Affecting Patient Decision Making
Authors: Patel Amit M. , Richards Philip S. , Wang Hom‐Lay , Inglehart Marita R. 
Published: April 2006

Background: This study explored which factors affected patients' decisions to pursue either surgical or non‐surgical periodontal treatment.Methods: Data were collected from 74 patients at a regularly scheduled periodontal appointment, at which each patient was told that periodontal treatment was needed, and 2 weeks following the actual treatment. The surveys assessed the patients' decisions and potential determinants of these decisions. The dental anxiety scale‐revised, the state‐trait anxiety inventory, and the Iowa dental control index were used to measure psychosocial factors.Results: Patients who decided to have surgery did not differ from patients who decided against surgery in sociodemographic variables such as gender, age, education, and socioeconomic status, nor in their desire for control over the treatment decision. However, they had less dental fear and less general anxiety than the non‐surgery patients. Although the two patient groups did not differ in their responses concerning how well the dentists had informed them about the procedure, they differed in the degree of trust and rapport with their dentists.Conclusions: The less dentally fearful and anxious patients were in general and the more they trusted their provider and felt they had good rapport, the more likely they were to accept surgical periodontal treatment. These results stress the importance of good patient‐provider communication.
Modulation of Phagocytosis, Chemotaxis, and Adhesion of Neutrophils by Areca Nut Extracts
Authors: Hung Shan‐Ling , Lee Ya‐Yun , Liu Tsung‐Yun , Peng Ji‐Lung , Cheng Yi‐Yun , Chen Yen‐Ting 
Published: April 2006

Background: A higher prevalence of periodontal diseases among areca chewers than non‐areca chewers has been demonstrated. Neutrophils, representing the first line of the host defense mechanism against microbial infection, play important roles in maintaining periodontal health. This study determined the possible effects of areca nut on phagocytosis, chemotaxis, and adhesion of human neutrophils.Methods: Aqueous extracts of ripe areca nut without husk (rANE) and fresh and tender areca nut with husk (tANE) were examined for their effects on neutrophil phagocytosis using flow cytometry and confocal laser scanning microscopy. The effects of rANE and tANE on chemotaxis and adhesion of neutrophils to human aortic endothelial cells were examined using fluorescence‐labeled neutrophils.Results: Both rANE and tANE inhibited the phagocytic activity of neutrophils in a dose‐dependent manner. The levels of internalized fluorescent bacteria in neutrophils decreased after ANE treatment. However, exposure of neutrophils to rANE and tANE stimulated the chemotaxis activity of neutrophils to N‐formyl‐Met‐Leu‐Phe (fMLP) and enhanced adhesion of neutrophils to human aortic endothelial cells in a dose‐dependent manner. Moreover, treatment of neutrophils with rANE was more effective than incubation with tANE.Conclusions: Components of areca nut inhibited phagocytosis activity of neutrophils but enhanced chemotaxis and adhesion of neutrophils. Alterations in functions of neutrophils may lead to signs of clinical diseases associated with areca chewing. The components in ANEs that are responsible for these observations remain to be elucidated.
Fabrication of Cultured Oral Gingiva by Tissue Engineering Techniques Without Materials of Animal Origin
Authors: Yamada Kazuto , Yamaura Junji , Katoh Masakazu , Hata Ken‐ichiro , Okuda Kazuhiro , Yoshie Hiromasa 
Published: April 2006

Background: Cultured gingival substitute has been found to be a useful graft material for treatment of gingival recession. However, such substitutes include xenograft derivative materials that involve concomitant risk of viral contamination. To eliminate this risk, we designed new gingival substitutes made of recombinant human collagen types I and III sponges and cultured these substitutes in animal‐free media (HFDM‐1).Methods: Gingival fibroblasts were seeded onto sponges of type I or III recombinant collagen. These sponges were cultured in Dulbecco's modified Eagle's medium (DMEM) with 10% fetal bovine serum (FBS), HFDM‐1 with 2% human serum (HS), or HFDM‐1. Fibroblast proliferation in these samples was compared using the cell‐counting kit assay. Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) released into the cultured media were examined by enzyme‐linked immunosorbent assay.Results: The fibroblasts proliferated significantly in all six combinations of collagen and medium types. The fibroblast growth rate after 9 days of culture was equal between HFDM‐1 with 2% HS and DMEM with 10% FBS. The type III collagen sponge showed a higher fibroblast growth rate than the type I sponge. VEGF concentrations in HFDM‐1 with 2% HS were higher than those in other media. The highest HGF levels were detected in DMEM with 10% FBS.Conclusions: The new cultured gingival substitute containing no animal‐derived materials produced good cell proliferation and VEGF release. The results suggested that the substitute may provide a new tool for the treatment of gingival recession.
prtH in Tannerella forsythensis Is Not Associated With Periodontitis
Authors: van der Reijden Wil A. , Bosch‐Tijhof Caroline J. , Strooker Hans , van Winkelhoff Arie Jan 
Published: April 2006

Background: It has been suggested that prtH in Tannerella forsythensis encodes for a cystein proteinase that is associated with its pathogenic potential and can discriminate between periodontal health and disease. The aim of this investigation was to further establish this potentially important observation.Methods: A group of 33 consecutive adult patients with periodontitis (mean age: 47.6 ± 10.1 years) harboring T. forsythensis was selected to investigate the presence of prtH by polymerase chain reaction (PCR). The T. forsythensis strains were isolated by anaerobic culture techniques. To investigate the association of this gene with periodontitis, a group of 14 age‐matched subjects (mean age: 56.4 ± 6.9 years) without any signs of periodontal disease (probing depths <3 mm and no radiographic attachment loss) was tested for comparison. Pure isolates and crude subgingival plaque samples were used as a template for the PCR.Results: In the group of 33 T. forsythensis‐positive patients, we found two T. forsythensis isolates to be prtH negative. Despite repeated analyses, testing of the whole subgingival plaque samples revealed only 17 of 33 samples to be prtH positive. The T. forsythensis isolates from the 14 periodontally healthy subjects were all prtH positive. The odds ratio of the presence of prtH in T. forsythensis in periodontitis patients versus healthy controls is 1.06 (P >0.05).Conclusions: On the basis of our data, we conclude that the presence of prtH in T. forsythensis is not discriminative for patients with T. forsythensis‐associated periodontitis compared to healthy carriers of T. forsythensis. In addition, the use of whole subgingival plaque samples to test for the prevalence of prtH in bacteria appeared unreliable. Culture of the microorganism is an important condition to receive a sufficient amount of template DNA to detect the specific locus of the genome.
Gingival Crevicular Fluid Leptin Levels in Periodontitis Patients With Long‐Term and Heavy Smoking
Authors: Bozkurt F. Yeşim , Yetkin Ay Z. , Sütçü R. , Delibaş N. , Demirel R. 
Published: April 2006

Background: The aim of the present study was to evaluate gingival crevicular fluid (GCF) leptin levels and the influence of long‐term and heavy smoking on GCF leptin levels in patients with chronic periodontitis.Methods: In this study, 143 individuals were divided into three groups: non‐smokers (NS), smokers (S), and control (C). Three subgroups of NS and S were grouped as follows: a) probing depth (PD) ≤3 mm; b) PD = 4 to 5 mm; and c) PD >5 mm. For each patient, PD, gingival index (GI), plaque index (PI), gingival bleeding time index (GBTI), and clinical attachment level (CAL) values were recorded. The GCF leptin levels obtained from sampling sites were determined by using enzyme‐linked immunosorbent assay kits.Results: The GCF leptin levels were found significantly lower in the a and b subgroups in the S group than those in the NS group (P <0.05). The inflammatory markers GI and GBTI showed significant correlations with leptin in NS (P <0.05).Conclusions: Our results suggest that higher leptin GCF levels in healthy sites in periodontitis patients may play a protective role in periodontal disease. Further studies are needed to determine the cellular origin of the leptin in the gingiva and the effect of plasma leptin levels on GCF leptin concentrations.
Gingival Crevicular Fluid Matrix Metalloproteinase‐25 and ‐26 Levels in Periodontal Disease
Authors: Emingil Gülnur , Kuula Heidi , Sorsa Timo , Atilla Gül 
Published: April 2006

Background: Tissue destruction associated with the progression of periodontal disease is caused by a cascade of host and microbial proteolytic enzymes. Host‐derived matrix metalloproteinases (MMPs) play an important role in the degradation of the extracellular matrix. Leukolysin/membrane‐type 6 (MT‐6)/MMP‐25, the latest member of the MT‐MMP subgroup of the MMP family, is primarily expressed by neutrophils and involved in extracellular matrix turnover. Matrilysin‐2/MMP‐26 (endometase), a novel member of the matrilysin subgroup of the MMP family, can degrade the extracellular matrix, α1‐antitrypsin, and activate pro‐MMP‐9. Our study aimed to examine the levels, molecular forms, and degrees of activation of MMP‐25 and MMP‐26 in gingival crevicular fluid (GCF) from patients with different periodontal diseases.Methods: A total of 105 subjects, 35 with generalized aggressive periodontitis (GAgP), 29 with chronic periodontitis (CP), 20 with gingivitis, and 21 periodontally healthy subjects, were included in this study. Periodontal status was evaluated by measuring probing depth, clinical attachment loss, presence of bleeding on probing, and plaque. GCF MMP‐25 and MMP‐26 levels were analyzed by computer‐quantitated Western immunoblotting using specific antibodies.Results: The 57‐kDa soluble pro‐MMP‐25 and 45‐ to 47‐kDa active form of MMP‐25 were detected by Western immunoblots in CP and GAgP GCF, and lesser levels of these soluble MMP‐25 immunoreactive bands were detected in gingivitis GCF. An enhanced and similar degree of MMP‐25 activation was found in GAgP, CP, and gingivitis groups. There were no detectable MMP‐25 immunoreactivities in the healthy subjects' GCF. GAgP and CP groups had elevated GCF MMP‐26 levels and degrees of activation compared to the gingivitis and healthy groups (P <0.008). The gingivitis group had higher GCF MMP‐26 levels and degree of activation compared to the healthy group (P <0.008).Conclusions: The present study demonstrated the presence of soluble or shed forms of MMP‐25 and MMP‐26 in GCF of patients with different periodontal diseases. Increased levels and activation of MMP‐25 and MMP‐26 in GCF are associated with an enhanced severity of periodontal inflammation, suggesting that these novel MMPs can participate in the progression of periodontal diseases. They may prove to be diagnostically useful and could be targets of medication in the future.
Lasers in Periodontics: A Review of the Literature
Authors: Cobb Charles M. 
Published: April 2006

Background: Despite the large number of publications, there is still controversy among clinicians regarding the application of dental lasers to the treatment of chronic periodontitis. The purpose of this review is to analyze the peer‐reviewed research literature to determine the state of the science concerning the application of lasers to common oral soft tissue problems, root surface detoxification, and the treatment of chronic periodontitis.Methods: A comprehensive computer‐based search combined the following databases into one search: Medline, Current Contents, and the Cumulated Index of Nursing and Allied Health. This search also used key words. In addition, hand searches were done for several journals not cataloged in the databases, and the reference lists from published articles were checked. All articles were considered individually to eliminate non‐peer‐reviewed articles, those dealing with commercial laser technology, and those considered by the author to be purely opinion articles, leaving 278 possible articles.Results: There is a considerable conflict in results for both laboratory studies and clinical trials, even when using the same laser wavelength. A meaningful comparison between various clinical studies or between laser and conventional therapy is difficult at best and likely impossible at the present. Reasons for this dilemma are several, such as different laser wavelengths; wide variations in laser parameters; insufficient reporting of parameters that, in turn, does not allow calculation of energy density; differences in experimental design, lack of proper controls, and differences in severity of disease and treatment protocols; and measurement of different clinical endpoints.Conclusions: Based on this review of the literature, there is a great need to develop an evidence‐based approach to the use of lasers for the treatment of chronic periodontitis. Simply put, there is insufficient evidence to suggest that any specific wavelength of laser is superior to the traditional modalities of therapy. Current evidence does suggest that use of the Nd:YAG or Er:YAG wavelengths for treatment of chronic periodontitis may be equivalent to scaling and root planing (SRP) with respect to reduction in probing depth and subgingival bacterial populations. However, if gain in clinical attachment level is considered the gold standard for non‐surgical periodontal therapy, then the evidence supporting laser‐mediated periodontal treatment over traditional therapy is minimal at best. Lastly, there is limited evidence suggesting that lasers used in an adjunctive capacity to SRP may provide some additional benefit.
Convergence analysis of blind image deconvolution via dispersion minimization
Authors: Vural C. , Sethares W. A. 
Published: April 2006

AbstractA new non‐linear adaptive filter called blind image deconvolution via dispersion minimization has recently been proposed for restoring noisy blurred images blindly. This is essentially a two‐dimensional version of the constant modulus algorithm that is well known in the field of blind equalization. The two‐dimensional extension has been shown capable of reconstructing noisy blurred images using partial a priori information about the true image and the point spread function in a variety of situations by means of simulations. This paper analyses the behaviour of the algorithm by investigating the static properties of the cost function and the dynamic convergence of the parameter estimates. The theoretical results are supported with computer simulations. Copyright © 2006 John Wiley & Sons, Ltd.
High Strength Nanocrystalline Ni‐Co Alloy with Enhanced Tensile Ductility
Authors: Gu C. , Lian J. , Jiang Z. 
Published: April 2006

Nanocrystalline Ni‐1.7%Co alloy exhibited high ultimate tensile strength of about 1600 MPa and enhanced ductility of 8‐9.6% over a wide strain rate range of 1.04 × 10–6–1.04 s–1 revealed by tensile tests at room temperature. The typical tradeoff characteristic between yield stress and elongation to failure would make this Ni‐1.7%Co alloy for potential use in different applications.