bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ridge Preservation Using a Composite Bone Graft and a Bioabsorbable Membrane With and Without Primary Wound Closure: A Comparative Clinical Trial
Authors: Engler‐Hamm Daniel , Cheung Wai S. , Yen Alec , Stark Paul C. , Griffin Terrence 
Published: November 2010

Background: The aim of this single‐masked, randomized controlled clinical trial is to compare hard and soft tissue changes after ridge preservation performed with (control, RPc) and without (test, RPe) primary soft tissue closure in a split‐mouth design.Methods: Eleven patients completed this 6‐month trial. Extraction and ridge preservation were performed using a composite bone graft of inorganic bovine‐derived hydroxyapatite matrix and cell binding peptide P‐15 (ABM/P‐15), demineralized freeze‐dried bone allograft, and a copolymer bioabsorbable membrane. Primary wound closure was achieved on the control sites (RPc), whereas test sites (RPe) left the membrane exposed. Pocket probing depth on adjacent teeth, repositioning of the mucogingival junction, bone width, bone fill, and postoperative discomfort were assessed. Bone cores were obtained for histological examination.Results: Intragroup analyses for both groups demonstrated statistically significant mean reductions in probing depth (RPc: 0.42 mm, P = 0.012; RPe: 0.25 mm, P = 0.012) and bone width (RPc: 3 mm, P = 0.002; RPe: 3.42 mm, P <0.001). However, intergroup analysis did not find these parameters to be statistically different at 6 months. The test group showed statistically significant mean change in bone fill (7.21 mm; P <0.001). Compared to the control group, the test group showed statistically significant lower mean postoperative discomfort (RPc 4 versus RPe 2; P = 0.002). Histomorphometric analysis showed presence of 0% to 40% of ABM/P‐15 and 5% to 20% of new bone formation in both groups. Comparison of clinical variables between the two groups at 6 months revealed that the mucogingival junction was statistically significantly more coronally displaced in the control group than in the test group, with a mean of 3.83 mm versus 1.21 mm (P = 0.002).Conclusions: Ridge preservation without flap advancement preserves more keratinized tissue and has less postoperative discomfort and swelling. Although ridge preservation is performed with either method, ≈27% to 30% of bone width is lost.
Expression of Hypoxia‐Inducible Factor‐1α in Human Periodontal Tissue
Authors: Ng King‐Tung , Li Jing‐Ping , Ng Kwong Man , Tipoe George L. , Leung W. Keung , Fung Man‐Lung 
Published: November 2010

Background: Hypoxia‐inducible factor (HIF)‐1 is a key transcription factor responding to hypoxia. It is composed of an oxygen‐sensitive α subunit (HIF‐1α) and a constitutively expressed β subunit. Increasing evidence indicates an essential role for HIF‐1α in infection and immunity. Because inflamed periodontium is thought to be hypoxic, we hypothesize that HIF‐1α is expressed and related to its upstream regulator tumor necrosis factor (TNF)‐α and downstream effecter vascular endothelial growth factor (VEGF).Methods: Human gingival biopsies were collected from advanced periodontitis sites and clinically healthy sites, and immunohistochemically examined for HIF‐1α and VEGF peptides. The messenger ribonucleic acid (mRNA) and protein levels of HIF‐1α, VEGF, and TNF‐α in the biopsies were then assessed by reverse transcription polymerase chain reaction and Western blotting.Results: HIF‐1α–positive immunoreactivity was detected in the nuclei of epithelial and endothelial cells. In periodontal pockets, there was a marked increase in the proportion of fibroblast‐like cells and leukocyte‐like cells expressing HIF‐1α. Protein levels of HIF‐1α, VEGF, and TNF‐α were significantly higher in periodontal pockets than in control gingival samples. The mRNA expression of VEGF and TNF‐α was also increased in periodontal pockets.Conclusion: HIF‐1α is expressed in healthy and diseased periodontium and may be related to TNF‐α and VEGF function during periodontitis.
Simvastatin Application to Augment Facial Jaw Bone in a Dog Model: Pilot Study
Authors: Rutledge John , Schieber Matthew D. , Chamberlain Judd M. , Byarlay Matthew , Killeen Amy C. , Giannini Peter J. , Marx David B. , Reinhardt Richard A. 
Published: November 2010

Background: Locally injected simvastatin (SIM) has been shown to induce bone growth in rat models. The purpose of this study is to evaluate the effects of locally injected simvastatin in several human‐like clinical situations in a beagle dog model.Methods: Four beagle dogs completed the study and were used in a split‐mouth design. Dehiscence defects of 5 × 3 mm were created bilaterally on the lateral aspect of the mandibular second premolar (PM2) mesial roots including removal of root cementum. At the same surgery, porous hydroxyapatite–collagen grafts with resorbable membranes with or without 10‐mg SIM were placed buccal to the mandibular first molars (M1). One week later, three weekly local injections of 10‐mg SIM in ethanol and contralateral ethanol alone were initiated at three sites through the buccal mucosa: 1) 6 mm apical to the cemento‐enamel junction (CEJ) of the maxillary fourth premolar (PM4; thin bone over root); 2) 6 mm apical to the CEJ of PM2 (dehiscence defect); and 3) 10 mm distoapical to the CEJ of the maxillary canine (edentulous ridge). Dogs were euthanized 2 months after the final injections. Block sections were harvested and specimens were decalcified and stained with hematoxylin and eosin. Histomorphometry was performed using digitized photographs and analyzed with distribution‐free rank tests.Results: Regarding M1, the distance between CEJ and the alveolar crest was significantly more coronal in the SIM group (P = 0.038). Regarding the edentulous ridge, the width of new bone was significantly greater in SIM injection specimens (P = 0.0164). Regarding PM2, buccal bone in the dehiscence defects lacking periosteum was not augmented in the SIM group. Regarding PM4, the total width of bone 5 mm apical to the coronal height of contour (thin buccal bone covering the root) was significantly wider on the SIM side (SIM, 0.63 ± 0.53 mm; contralateral ethanol alone, 0.25 ± 0.19 mm; P = 0.0098).Conclusion: Locally injected SIM has the ability to induce modest amounts of new bone formation in closed injection sites over a periosteal surface.
Serum Levels of C‐Reactive Protein in Adolescents With Periodontitis
Authors: López Rodrigo , Baelum Vibeke , Hedegaard Chris Juul , Bendtzen Klaus 
Published: November 2010

Background: The results of several cross‐sectional studies suggested a relationship between periodontitis and higher serum levels of C‐reactive protein (CRP). Most of these studies were restricted to adult study groups with severe periodontal inflammation, and the potential effects of confounding factors were frequently overlooked.Methods: A case‐referent study comprised of 87 adolescent cases who presented with clinical attachment loss ≥3 mm recorded in ≥2 of 16 teeth and 73 controls who did not fulfill these criteria was nested in a fully enumerated adolescent population. Venous blood samples were obtained, and CRP levels were quantified, using a high‐sensitive bead‐based flow cytometric assay. The Mann‐Whitney U test was used to assess overall differences between groups.Results: The median serum CRP values for cases and controls were 64 ng/ml (interquartile range: 27 to 234 ng/ml) and 55 ng/ml (31 to 183 ng/ml), respectively (P = 0.8).Conclusions: Serum levels of CRP were not significantly higher among subjects with periodontitis than among controls. However, a statistically significant positive association between percentages of sites with bleeding on probing and log‐transformed CRP values was observed.
Bacterial Colonization of the Implant–Abutment Interface Using an In Vitro Dynamic Loading Model
Authors: Koutouzis Theofilos , Wallet Shannon , Calderon Nadia , Lundgren Tord 
Published: November 2010

Background: Previously, we demonstrated that the geometry of the fixture–abutment interface influences the risk of bacterial invasion into the internal part of the implant, although the contribution of loading on this invasion was not evaluated. The aim of the present study is to use an in vitro dynamic‐loading model to assess the potential risk for invasion of oral microorganisms into the fixture–abutment interface microgap of dental implants with different fixture–abutment connection characteristics.Methods: Twenty‐eight implants were divided into two groups (n = 14 per group) based on their microgap dynamics. Group 1 was comprised of fixtures with internal Morse‐taper connection that connected to standard abutments. Group 2 was comprised of implants with a four‐groove conical internal connection that connected to multibase abutments. The specimens were immersed in a bacterial solution of Escherichia coli and loaded with 500,000 cycles of 15 N in a wear simulator. After disconnection of fixtures and abutments, microbial samples were taken from the threaded portion of the abutment, plated, and cultured under appropriate conditions. The difference between loosening and tightening torque value was also measured.Results: One of the 14 samples in Group 1 and 12 of the 14 of samples in Group 2 developed multiple colony forming units for E. coli. Implants in Group 1 exhibited an increase in torque value in contrast to implants in Group 2, which exhibited a decrease.Conclusion: This study indicates that differences in implant design may affect the potential risk for invasion of oral microorganisms into the fixture–abutment interface microgap under dynamic‐loading conditions.
Immediate Dental Implant Placement in HIV‐Positive Patients Receiving Highly Active Antiretroviral Therapy: A Report of Two Cases and a Review of the Literature of Implants Placed in HIV‐Positive Individuals
Authors: Kolhatkar Shilpa , Khalid Syed , Rolecki Anne , Bhola Monish , Winkler James R. 
Published: November 2010

Background: There are numerous reports of oral surgical procedures in patients undergoing highly active antiretroviral therapy. In the general population, the success of immediate implant placement for replacing teeth is well documented. The number of human immunodeficiency virus (HIV)‐positive patients seeking comprehensive dental care, including implant therapy, continues to increase. Aside from a solitary case report published 12 years ago, there is very limited evidence describing immediate implant placement in the HIV‐positive population. The two cases described herein demonstrate successful immediate implant placement in this population.Methods: Two white male patients aged 48 and 55 were scheduled to undergo extraction of a mandibular premolar. Both patients were HIV‐positive, receiving highly active antiretroviral therapy, and were closely monitored by their physicians. On the day of the surgical procedure, atraumatic extractions were completed, osteotomies prepared in the ideal orientation, and implants placed. The bone‐to‐implant gap was >1.5 mm in Case 2, which required particulate bone graft placement. Case 1 did not need additional bone grafting. In Case 1, the healing abutment was placed at the time of implant placement, whereas a second‐stage surgical procedure was performed for Case 2.Results: Patients were seen at 2 and 4 weeks for postoperative assessment. No adverse postoperative sequelae were observed, and both implants integrated and were successfully restored.Conclusions: Immediate implant placement in HIV‐positive patients is a viable and successful treatment option. To our knowledge, only one other similar report exists. It is hoped that this case report adds to the body of evidence supporting immediate implant placement in the HIV‐positive population.
Primary Gingival Pseudoepitheliomatous Hyperplasia with Periodontal Findings: A Rare Case Report
Authors: Thorat Manojkumar , Pradeep A.R. , Pallavi Borse 
Published: November 2010

Background: This paper is the first‐ever report, to our knowledge, of a case of generalized primary gingival pseudoepitheliomatous hyperplasia(PEH) with significant periodontal findings in a 23‐year‐old Indian female patient. It explains the need to differentiate PEH from squamous cell carcinoma in diagnosis and treatment planning. The present article also reviews current immunohistologic staining methods used to differentiate PEH from squamous cell carcinoma.Methods: A two‐stage surgical approach was used to eliminate the lesion by gingivectomy and gingivoplasty under local anesthesia. Histopathologic examination of excised tissue was done to differentiate it from squamous cell carcinoma.Results: After 1‐year follow‐up, there was uneventful gingival healing and no recurrence of the lesion.Conclusions: Differentiation of PEH from squamous cell carcinoma of the gingiva is important for diagnosis and treatment. It is also important to consider PEH as a rare condition of gingival overgrowth.
Bone Reformation and Implant Integration following Maxillary Sinus Membrane Elevation: An Experimental Study in Primates
Authors: Palma Vinicius C , Magro‐Filho Osvaldo , De Oliveria José Américo , Lundgren Stefan , Salata Luiz A , Sennerby Lars 
Published: November 2010

ABSTRACTBackground:  Recent clinical studies have described maxillary sinus floor augmentation by simply elevating the maxillary sinus membrane without the use of adjunctive grafting materials.Purpose:  This experimental study aimed at comparing the histologic outcomes of sinus membrane elevation and simultaneous placement of implants with and without adjunctive autogenous bone grafts. The purpose was also to investigate the role played by the implant surface in osseointegration under such circumstances.Materials and Methods:  Four tufted capuchin primates had all upper premolars and the first molar extracted bilaterally. Four months later, the animals underwent maxillary sinus membrane elevation surgery using a replaceable bone window technique. The schneiderian membrane was kept elevated by insertion of two implants (turned and oxidized, Brånemark System®, Nobel Biocare AB, Göteborg, Sweden) in both sinuses. The right sinus was left with no additional treatment, whereas the left sinus was filled with autogenous bone graft. Implant stability was assessed through resonance frequency analysis (OsstellTM, Integration Diagnostics AB, Göteborg, Sweden) at installation and at sacrifice. The pattern of bone formation in the experimental sites and related to the different implant surfaces was investigated using fluorochromes. The animals were sacrificed 6 months after the maxillary sinus floor augmentation procedure for histology and histomorphometry (bone‐implant contact, bone area in threads, and bone area in rectangle).Results:  The results showed no differences between membrane‐elevated and grafted sites regarding implant stability, bone‐implant contacts, and bone area within and outside implant threads. The oxidized implants exhibited improved integration compared with turned ones as higher values of bone‐implant contact and bone area within threads were observed.Conclusions:  The amount of augmented bone tissue in the maxillary sinus after sinus membrane elevation with or without adjunctive autogenous bone grafts does not differ after 6 months of healing. New bone is frequently deposited in contact with the schneiderian membrane in coagulum‐alone sites, indicating the osteoinductive potential of the membrane. Oxidized implants show a stronger bone tissue response than turned implants in sinus floor augmentation procedures.
Influence of Titanium Surface Charge on Fibroblast Adhesion
Authors: Hamdan Mohammad , Blanco Luis , Khraisat Ameen , Tresguerres Isabel F. 
Published: November 2010

ABSTRACTBackground:  Although dental implants have a high success rate, failure owing to the absence of adhesion between the gingival connective tissue and the implant surface is still being reported.Purpose:  This study was designed to evaluate the effect of a titanium surface charge on fibroblast adhesion.Material and Methods:  An electrical chamber was custom‐made to generate negative and positive surface charges on commercially pure titanium cylinders with a potential difference of 4.5 V. Twenty‐seven titanium cylinders were divided into three experimental groups. In each group, cell attachment to a positively charged titanium cylinder, a negatively charged titanium cylinder, and a titanium cylinder (control) was studied at three time intervals of 15, 30, and 60 minutes. NCTC clone 929 fibroblasts were used in these experiments. The effect of the potential difference in the pH of Dulbecco's Modified Eagle Medium (DMEM) was also evaluated using two new specimens at time intervals of 15, 30, 60, and 80 minutes.Results:  The fibroblast cell attachment was more statistically significant to the positively charged titanium cylinder than the negatively charged titanium cylinder (p =.002) and the control (p=.000), whereas the cell adhesion difference between the control and the negatively charged titanium cylinder was not statistically significant (p=.808). The range of pH difference of the DMEM in the negative and positive parts of the electrical chamber was 0.46 and 0.30, respectively.Conclusion:  Within the limitations of this in vitro study, the positive surface charge of the titanium cylinder results in significantly favorable cell adhesion.
Patient Evaluation after Treatment with Maxillary Implant‐Supported Overdentures
Authors: Kronström Mats , Widbom Christin , Söderfeldt Björn 
Published: November 2010

ABSTRACTPurpose:  To evaluate and compare outcome among patients after implant overdenture treatment in the maxilla.Materials and Methods:  The study sample comprised two groups of patients: group 1, in which the patients were planned for overdenture treatment, and group 2, in which the patients originally were planned for a fixed prosthesis in the maxilla but had overdenture treatment owing to implant failures, resulting in an insufficient number of implants to support a fixed prosthesis. All patients treated with maxillary implant‐supported overdentures in the Department of Prosthetic Dentistry, Central Hospital, Skövde, Sweden, between 1993 and 2002 received a questionnaire at their yearly follow‐up visit with nine questions related to their treatment. All questions had visual analogue scale response alternatives ranging from a negative to a positive opinion.Results:  Nineteen patients, 10 in group 1 and 9 in group 2, completed the questionnaire, yielding a response rate of 86%. Both groups expressed a high satisfaction rate, and few regretted their choice of treatment. Patients planned for overdenture treatment (group 1) reported significantly fewer speech problems after treatment compared with those originally planned for a fixed prosthesis (group 2, p < .05). No other significant differences between the two groups were seen.Conclusion:  Within the limitations of the present study, it can be concluded that maxillary implant overdenture treatment may be considered a viable option among patients with an insufficient number of implants for a fixed prosthesis.
Histologic Evaluation of Brånemark Clinic Oral Implants Retrieved from Grafted Sites
Authors: Bolind Pia , Johansson Carina B. , Johansson Petra , Van Steenberghe Daniel , Albrektsson Tomas 
Published: November 2010

ABSTRACTPurpose:  The aim of this report is to quantitatively and qualitatively describe the bone tissue response to Brånemark implants retrieved from grafted sites in patients.Materials and Method:  The material consists of consecutively received Brånemark implants retrieved from grafted sites. Thirty‐five of these implants, retrieved from 16 patients, were suitable for the histologic evaluation of undecalcified sections in the light microscope.Results:  The unloaded implants were mainly lined with soft tissue, and sparse bone‐implant contact was observed only in some sections. The loaded implants, with the exception of one implant removed due to mobility, had mature and new bone‐implant contact. Resorption of graft through cutting cone structures was detected. Cement lines were found separating bone‐like tissue albeit no cellular content and bone tissue with detectable osteocytes.Conclusion:  In this heterogeneous group of implants from grafted sites, the unloaded implants showed limited bone‐implant contact. The autografts showed seemingly mixed viability as judged by the cell content in the osteocyte lacunae and cement lines separating areas with filled and empty lacunae.
Trace metal concentration in wild avian species from Campania, Italy
Authors: Zaccaroni Annalisa , Niccoli Camilla , Andreani Giulia , Scaravelli Dino , Ferrante Maria , Lucisano Antonia , Isani Gloria 
Published: November 2010

Abstract
This study was conducted to determine heavy metals concentrations in tissues of 94 birds belonging to different species from coastal areas of Naples and Salerno (Southern Italy) in order to provide baseline data concerning trace element levels in wild birds living in or close to an area characterized by high anthropogenic impact. Additional aim of this study was to verify if diet influenced metal accumulation, so birds were classified as birds of prey, fish eating birds and insectivorous birds. Kidney was the primary organ for Cd accumulation in all groups considered, Pb was accumulated preferentially in bone, whereas Hg showed high values in liver of fish eating birds. Zn showed the highest mean concentrations, while Cu levels were one order of magnitude less. The variance analysis with respect to feeding habits disclosed only a lower accumulation of Hg in insectivores with respect to the other groups. For all metals, the concentrations measured in tissues should be considered indicative of chronic exposure to low, “background” environmental levels and/or to the presence of low bioavailable metals in the environment. In addition, metal levels were not of toxicological concern, being always well below the toxic thresholds defined for each metal.
Selenium determination in tissue samples of Nile tilapia using ultrasound-assisted extraction
Authors: Silva Fábio , Padilha Cilene , Castro Gustavo , Roldan Paulo , Araujo Nogueira Ana , Moraes Paula , Padilha Pedro 
Published: November 2010

Abstract
This paper proposes a method to determine selenium in samples of fish muscle and liver tissue using ultrasound assisted extraction process, and analysed by graphite furnace atomic absorption spectrometry (GFAAS). The selenium content was extracted by 0.10 M HCl at the optimal extraction conditions which were established as follows: sample mass of 100 mg; granulometry of the sample <60 µm; sonication time of five 40 s cycles; and sonication power of 136 W. The selenium determinations were performed by GFAAS, at a drying temperature of 120°C/250°C, pyrolysis temperature of 1300°C, atomization temperature of 2300°C, and cleaning temperature of 2800°C. Palladium nitrate was used as a chemical modifier coinjected with the samples, and tungsten as a permanent modifier. The concentration of selenium determined in the pool of fish muscle and liver tissue were 280.4±4.2 e 592.3±6.7 μg kg−1, respectively. The accuracy and precision of the proposed extraction method were evaluated using certified standard Bovine Muscle — NIST 8414. The results obtained by the ultrasonic extraction method were equivalent to those obtained by the method of acid mineralization of samples in a microwave oven