bluuebunny/crossref_metadata_2025 huggingface dataset:
Medical Grade Calcium Sulfate Hemihydrate in Healing of Human Extraction Sockets: Clinical and Histological Observations at 3 Months
Authors: Guarnieri Renzo , Pecora Gabriele , Fini Milena , Aldini Nicolo′ Nicoli , Giardino Roberto , Orsini Giovanna , Piattelli Adriano
Published: February 2005

Background: Following tooth extraction, remodeling and resorption of the alveolar bone at the extraction site characterize wound healing. This produces a reduction in ridge volume and difficulties in delayed placement of implants in an ideal position. Medical grade calcium sulfate hemihydrate (MGCSH) has been proposed as a graft material in extraction sockets to minimize the reduction in ridge volume. The aim of the present study was to investigate the influence of MGCSH on the histopathologic pattern of intrasocket regenerated bone and to evaluate histologically the healed MGCSH grafted extraction socket site 3 months postextraction

Methods: MGCSH was grafted in 10 fresh human extraction sockets in 10 patients. Five post‐extraction sockets were used as controls. At 3 months a cylindrical tissue specimen, 2.5 mm in diameter, was trephined from the previously grafted site followed by implant placement. Non‐decalcified specimens were sectioned at a cross‐horizontal plane and stained with fast green, toluidine blue, and Van Kossa stains for histological and histomorphometrical examination.

Results: Histologically, MGCSH was not observed in most of the specimens. Newly formed bone with lamellar arrangements was identified in all the horizontal sections with no difference between apical, medium, and coronal areas. The mean trabecular area in the coronal sections was 58.6% ± 9.2%; in the medium sections, 58.1% ± 6.2%; and in the apical sections, 58.3% ± 7.8%. The differences were not statistically significant.

Conclusion: MGCSH seems to be an ideal graft material in extraction socket bone regeneration because it is almost completely resorbable, and it allows a new trabecular bone arrangement at 3 months. J Periodontol 2004;75:902‐908.
Implant Therapy Following Liver Transplantation: Clinical and Microbiological Results After 10 Years
Authors: Heckmann Siegfried Martin , Heckmann Josef Georg , Linke Jens Julian , Hohenberger Werner , Mombelli Andrea
Published: February 2005

Background: The number of immunocompromised patients is increasing as a consequence of successful organ transplantation. Placing dental implants in these patients has been questioned because of their increased risk for infections. The 10‐year follow‐up data of a 71‐year‐old liver transplant recipient with long‐term immunosuppressive therapy is reported. Six months after liver transplantation, two interforaminal implants were inserted in the edentulous mandible, and an overdenture using non‐rigid telescopic attachments was fabricated 3 months later.

Methods: Oral clinical parameters included the modified plaque index, sulcus fluid flow rate, modified bleeding index, probing depth, distance implant mucosa, attachment level, width of the keratinized mucosa and mobility values. The distance implant bone (DIB) was determined on digital panoramic radiographs. The levels of eight periodontal marker organisms were established using DNA probe technology. Additionally, swabs of the edentulous oral mucosa were taken for microbiological culture and antimicrobial resistance testing.

Results:The peri‐implant parameters were within normal ranges indicating a stable osseointegration with moderate vertical bone loss. Actinobacillus actinomycetemcomitans, Tannerella forsythensis, Campylobacter rectus, and Treponema denticola were not detected. Low levels of levels of Porphyromonas gingivalis, Fusobacterium Porphyromonas gingivalis, Fusobacterium nucleatum, and Eikenella corrodens were found. Prevotella intermedia was the only bacterium with a level higher than 104. The mucosal swabs indicated the presence of an abundant normal oral flora, including Escherichia coli and Candida albicans. The antibiogram revealed multiple resistance to antibiotics.

Conclusion: This case report suggests that immunocompromised patients can be successfully rehabilitated with dental implants. J Periodontol 2004;75:909‐913.
Bone Apposition in Surgical Bony Defects Following Orthodontic Movement: A Comparative Histomorphometric Study Between Root‐ and Periodontal Ligament‐Damaged and Periodontally Intact Rat Molars
Authors: Nemcovsky Carlos E. , Beny Leah , Shanberger Shirley , Feldman‐Herman Simona , Vardimon Alexander
Published: February 2005

Background: The influence of orthodontic tooth movement with diminished periodontal support is unclear. The aim of the present study was to evaluate bone healing in surgical defects following orthodontic tooth movement with and without periodontal ligament (PDL) and root surface damage.

Methods: The study comprised 33 adult male Wistar rats, divided into two groups: group 1 (n = 14) with bony defect and no root damage and group 2 (n = 19) with periodontal bony defect including root/PDL damage on the mesial root of the maxillary first molar. One week after a surgical defect was created, orthodontic protraction of the right maxillary first molar was initiated in both groups. After 2 weeks of protraction, retention of 1 week was established; at the end of this period block sections were made. Histomorphometric analysis through light microscopy of decalcified tissue was performed. Results were statistically analyzed using independent samples t test and analysis of variance (ANOVA) with repeated measures.

Results: Differences between groups in total area of bone defect and bone apposition were not statistically significant. Bone apposition calculated as percentage of the bone defect was significantly (t‐test) greater (P = 0.002) in group 2 (46.21%) than in group 1 (24.95%). Within each group, area of bone apposition was significantly (ANOVA) greater in the distal than in the mesial quadrants of the bony defect (P = 0.006) and in the apical than the occlusal ones (P = 0.021).

Conclusion: Following orthodontic tooth movement, periodontal bony defects showed enhanced bony healing compared with alveolar bone defects with no direct association with the periodontal attachment apparatus. J Periodontol 2004;75:1013‐1019.
Root Resorption in Chronic Periodontitis: A Morphometrical Study
Authors: Rodriguez‐Pato Raquel B.
Published: February 2005

Background: It has been previously observed that teeth with severe chronic periodontitis experience more transient external root resorptions than teeth with less severe disease.

Methods: Sixty‐six teeth diagnosed with different levels of chronic periodontitis in 48 patients were observed with a light microscope. Main characteristics of teeth with root resorptions, as well as percentages of area and volume resorbed on each radicular third of the teeth, were determined.

Results: Over 80% (53) of the teeth exhibited resorption: 46.67% in group 1 (slight periodontitis); 85% in group 2 (moderate periodontitis); and 93.55% in group 3 (severe periodontitis). In group 1, the average resorption length was 295.65 μm and the average area, 11,212.45 μm2. In group 2 these measures were 519.09 and 25,678.102, respectively. In group 3, the average length was 675.95 μm, and the average area 36,925.06 μm2. Except for the resorbed volume on the apical third, the other resorption percentages were higher in group 3 (severe periodontitis) and smaller in the group 1 (slight periodontitis), but the location of the largest resorption percentages varied among the three groups.

Conclusions: The severity of periodontitis plays a major role in the presence and extent of transient external root resorption. In the three groups, most of the teeth showed resorptions on the apical third, but severity of periodontitis determined the location of the largest percentages of area and volume resorbed. J Periodontol 2004;75:1027‐1032.
Mast Cell Subpopulations in Gingival Overgrowth Induced by Immunosuppressive and Nifedipine Medication
Authors: Nurmenniemi Petri K. , Pernu Hilkka E. , Knuuttila Matti L.E.
Published: February 2005

Background: An immunohistochemical study was conducted to compare distributions of mast cell subpopulations in normal human gingiva and in gingival overgrowth induced by nifedipine and immunosuppressive medication.

Methods: Gingival samples were collected from 12 triplemedicated organ transplant recipients (immunosuppression group), 11 triple‐medicated organ transplant recipients taking nifedipine (immunosuppression plus nifedipine group), 11 nifedipine‐medicated cardiac outpatients (nifedipine group), and 20 generally healthy individuals (control group). Cryostat sections were stained with mAbs for tryptase and chymase, and an avidin‐biotin enzyme complex method was used to detect tryptase‐positive mast cells (MCT), tryptase‐ and chymase‐positive mast cells (MCTC), and chymase‐positive mast cells (MCC). Total numbers of labeled cells were determined in connective tissue beneath the sulcular epithelium, connective tissue beneath the oral epithelium, and middle connective tissue. Statistical analyses were conducted using the Kruskal‐Wallis test, the Mann‐Whitney U‐test, and Pearson's correlation test.

Results: In the three counting zones combined, numbers of MCTC cells and MCC cells were lower (P = 0.001 and P = 0.048, respectively) in the immunosuppression group than in the control group. The difference in numbers of MCTC cells was most marked in the middle connective tissue. Nifedipine medication had no effect on numbers of the mast cell subclasses.

Conclusions: Immunosuppressive medication without concomitant nifedipine decreases the numbers of MCTC and MCC in overgrown gingiva. Chymase‐positive mast cells may play a role in formation of gingival overgrowth, especially in patients receiving cyclosporin A (CsA) medication with no concomitant nifedipine. In this respect, nifedipine and CsA are different. J Periodontol 2004;75:933‐938.
Inhibition of Osteogenesis In Vitro by a Cigarette Smoke‐Associated Hydrocarbon Combined With Porphyromonas gingivalis Lipopolysaccharide: Reversal by Resveratrol
Authors: Andreou V. , D'Addario M. , Zohar R. , Sukhu B. , Casper R.F. , Ellen R.P. , Tenenbaum H.C.
Published: February 2005

Background: Smoking and infection with Gram‐negative bacterial pathogens are risk factors for alveolar bone loss. The aims of this study were: 1) to examine the combined effects of an aryl hydrocarbon, benzo[a]pyrene (BaP), that is concentrated in cigarette smoke, and lipopolysaccharide (LPS) extracted from Porphyromonas gingivalis on osteogenesis in a rat bone marrow cell (RBMC) model of osteogenesis; and 2) to determine whether resveratrol (Res), an aryl hydrocarbon receptor antagonist, could reverse the putative inhibitory effects of BaP + LPS on osteogenesis.

Methods: LPS of P. gingivalis strain 2561 was introduced in various concentrations to the RBMC in 96‐well plates and kept in culture for 8 to 12 days. The same protocol was used for studying BaP and LPS + BaP combinations. Following the incubation periods, parameters of osteogenesis were measured, including formation of mineralized bone nodules, alkaline phosphatase activity, and total cell protein. Transcription of the proinflammatory cytokine interleukin (IL)‐1β in the cultures was determined by reverse transcriptase polymerase chain reaction (RT‐PCR).

Results: Bone nodule formation generally decreased significantly with increasing LPS concentrations (P <0.05), whereas total cell protein decreased only slightly (P >0.05). BaP in previously high concentrations alone also caused a significant dose‐dependent decrease in bone nodule formation (P <0.05) but when half maximal doses were used, significant decreases were most often seen when LPS was added. Hence, in combination, the inhibitory effects of LPS + BaP on osteogenesis were additive, inhibiting bone nodule formation up to 9‐fold. Resveratrol partially reversed the inhibitory effects of low concentrations of LPS alone, and completely reversed the inhibition of nodule formation when low concentrations of LPS were combined with BaP. IL‐1β expression generally fluctuated inversely to the inhibitory activity of LPS, LPS + BaP, and LPS + BaP + Res combinations.

Conclusions: Smoke‐derived aryl hydrocarbons and bacterial LPS may act additively to inhibit bone formation. The findings may explain, in part, why net periodontal bone loss is greater and bone healing is less successful in smokers than non‐smokers with periodontal infections. Reversal of the inhibitory effects in vitro by resveratrol suggests that this phytoalexin should be studied further for its potential therapeutic value, given its aryl hydrocarbon receptor antagonism and apparent anti‐inflammatory activity. J Periodontol 2004;75:939‐948.
Periodontal Treatment With an Er:YAG Laser Compared to UltrasonicInstrumentation: A Pilot Study
Authors: Sculean Anton , Schwarz Frank , Berakdar Mohammad , Romanos George E. , Arweiler Nicole B. , Becker Jürgen
Published: February 2005

Background: The aim of the present study was to compare the effectiveness of an Er:YAG laser to that of ultrasonic scaling for non‐surgical periodontal treatment.

Methods: Twenty patients with moderate to advanced periodontal disease were randomly treated in a split‐mouth design with a single episode of subgingival debridement using either an Er:YAG laser device (160 mJ/pulse, 10 Hz) combined with a calculus detection system with fluorescence induced by 655 nm InGaAsP diode laser radiation (ERL), or an ultrasonic instrument (UI). Clinical assessments of full‐mouth plaque score (FMPS), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL) were made at baseline and at 3 and 6 months following therapy.

Results: No differences in any of the investigated parameters were observed at baseline between the two groups. The mean value of BOP decreased in the ERL group from 40% at baseline to 17% after 6 months (P <0.0001) and in the UI group from 46% at baseline to 15% after 6 months (P <0.0001). The sites treated with ERL demonstrated mean CAL gain of 1.48 ± 0.73 mm (P <0.001) and of 1.11 ± 0.59 mm (P <0.001) at 3 and 6 months, respectively. The sites treated with UI demonstrated mean CAL gain of 1.53 ± 0.67 mm (P <0.001) and of 1.11 ± 0.46 mm (P <0.001) at 3 and 6 months, respectively. No statistically significant differences were observed between the groups (P >0.05).

Conclusion: Within the limits of the present study, it can be concluded that both therapies led to significant improvements of the investigated clinical parameters. J Periodontol 2004;75:966‐973.
Immediate Implants Supporting Single Crown Restoration: A 4‐Year Prospective Study
Authors: Covani Ugo , Crespi Roberto , Cornelini Roberto , Barone Antonio
Published: February 2005

Background: The placement of implants at the time of tooth extraction has several clinical advantages, such as preservation of the alveolar ridge width and height and reduction of the restorative treatment time. The aim of this study was to evaluate the cumulative success rate of dental implants placed in fresh extraction sockets with and without guided bone regeneration (GBR) used to support a single crown restoration. All of the patients were preselected as candidates for implants.

Methods: Ninety‐five patients aged 20 to 68 years with 163 implants were included. All patients were partially edentulous and participated in a personally tailored recall schedule. The followup period was 48 months. Patients underwent a clinical and radiographic evaluation annually.

Results: The 4‐year cumulative success rate was 97%. Five of the 163 implants failed, two during the initial healing time, which were considered early failures and three a year after prosthetic rehabilitation, which were considered late failures. No failure of prosthetic rehabilitation was observed.

Conclusions: Implants placed into fresh extraction sockets with or without regenerative procedures and used to support single crown prosthesis showed a very high cumulative success rate (97%) in a 4‐year prospective study. Several observations should be made: 1) all the patients were preselected as candidates for implants and were following a strict oral hygiene regimen; 2) all efforts were made to reduce the number of cases requiring GBR procedures; 3) all the implants had an acid etched/sandblasted implant surface; and 4) all the prosthetic restorations were single crowns. J Periodontol 2004;75:982‐988.
Comparison of Keratinocyte Proliferation in Diabetic and Non‐Diabetic Inflamed Gingiva
Authors: Açikgoz Gükhan , Devrim İnci , Özdamar Şükrü
Published: February 2005

Background: Keratinocytes are chiefly cells of the epidermis but also constitute 90% of the gingival cells. The molecular mechanisms of proliferative activity in keratinization whereby diabetes alters periodontal physiology have not been elucidated. In this study, we aimed to investigate the role of gingival keratinocytes in hyperglycemic subjects by examining their mitotic activities.

Methods: We tested 30 patients with periodontitis, of whom 15 were type II diabetics and the remainder systemically healthy. Biopsies were obtained from the bottom of the deepest pocket in each subject by reverse beveled incision. Formalin‐fixed and paraffin‐embedded specimens were then processed for periodic acid‐Schiff (PAS)‐diastase histochemistry and proliferating cell nuclear antigen (PCNA) (P10). Immunohistochemical studies were employed to determine the presence of PCNA and were used to detect the proliferating potential of keratinocytes needed in synthesizing DNA. The expression of PCNA was evaluated using an immunoperoxidase technique and PC10 monoclonal antibody to PCNA. Mitotic index was calculated from basal cells. Statistical analysis employed the chi‐square test.

Results: No significant difference between the diabetic and nondiabetic patients was found in the mitotic index of the oral‐gingival epithelium.

Conclusion: Although the mitotic index in patients with diabetes was slightly lower, keratinization in the gingival tissues for both groups was essentially identical. J Periodontol 2004;75:989‐994.
Matrix Metalloproteinase‐2 May Be Involved With Increased Bone Loss Associated With Experimental Periodontitis and Smoking: A Study in Rats
Authors: Neto João Batista César , de Souza Ana Paula , Barbieri Deise , Moreno Heitor , Sallum Enilson Antonio , Nociti Francisco Humberto
Published: February 2005

Background: Smoking has been associated with periodontitis severity and is considered a risk factor for its development. It has been reported that matrix metalloproteinase (MMP) produced by host cells plays a major role in periodontal tissue destruction. Thus, the present study tested, in rats, the hypothesis that local increased levels of MMP‐2 would be associated with the enhanced periodontitis‐related bone loss after intermittent cigarette smoke inhalation (CSI).

Methods: Twenty‐seven adult male Wistar rats were used. A ligature was placed around one of the mandibular first molars of each animal and they were randomly assigned to the following control (N = 13) or CSI (N = 14) group. Sixty days later, the animals were sacrificed, the gingival tissues harvested, and the specimens processed for decalcified sections. Extracts from the gingival tissues were prepared and assayed for MMP‐2 expression.

Results: Intergroup comparisons (unligated sites) showed that CSI might directly affect alveolar bone (0.16 ± 0.03 mm2 versus 0.24 ± 0.09 mm2 for non‐smokers and smokers, respectively; P = 0.001). Moreover, CSI significantly enhanced bone loss resulting from experimental periodontitis (0.64 ± 0.36 mm2 versus 1.50 ± 0.50 mm2 for non‐smokers and smokers, respectively; P <0.05). In addition, zymography demonstrated that CSI also enhanced both MMP‐2 levels and activity in the gingival tissues around ligated teeth.

Conclusion: Within the limits of the present investigation, it can be assumed that the effect of CSI on MMP‐2 levels and activity may account for the increased periodontitis progression rate observed in smokers. J Periodontol 2004;75:995‐1000.
Periodontal Diseases and the Risk of Coronary Heart and Cerebrovascular Diseases: A Meta‐Analysis
Authors: Khader Yousef S. , Albashaireh Zakereyya S.M. , Alomari Mousa A.
Published: February 2005

Background: This meta‐analysis was conducted to examine the relationship between periodontal diseases and coronary heart diseases (CHD) and cerebrovascular diseases (CVD) in observational studies.

Methods: This study was based on seven cohort studies and four studies of other designs that met prestated inclusion criteria. Information on study design, year of publication, study location, sample size, study population, participant characteristics, measurement of risk factors, exposure and outcome measures, matching, controlling for confounders, and risk estimates was abstracted independently by two investigators using a standard protocol.

Results: Subjects with periodontitis had an overall adjusted risk of CHD that was 1.15 times (95% confidence interval [CI]: 1.06 to 1.25; P = 0.001) the risk for healthy subjects. There was no heterogeneity among the studies in the overall relative risk estimate (P = 0.472). As compared to healthy subjects, those with periodontitis had an overall adjusted relative risk of CVD of 1.13 (95% CI: 1.01 to 1.27; P = 0.032).

Conclusions: Findings indicated that periodontal infection increases the risk of CHD and CVD. However, this meta‐analysis provided no evidence for the existence of strong associations between periodontitis and CHD and CVD. Larger and bettercontrolled studies involving socially homogeneous populations and measuring specific periodontal pathogens are required to identify a definite association between periodontal disease and the risk of coronary heart disease and cerebrovascular disease. J Periodontol 2004;75:1046‐1053.
Morphometric Analysis of Implant‐Related Anatomy in Caucasian Skulls
Authors: Neiva Rodrigo F. , Gapski Ricardo , Wang Hom‐Lay
Published: February 2005

Background: Sequelae related to implant placement/advanced bone grafting procedures are a result of injury to surrounding anatomic structures. Damage may not necessarily lead to implant failure; however, it is the most common cause of legal action against the practitioner. This study aimed to describe morphological aspects and variations of the anatomy directly related to implant treatment.

Methods: Morphometric analyses were performed in 22 Caucasian skulls. Measurements of the mental foramen (MF) included height (MF‐H), width (MF‐W), and location in relation to other known anatomical landmarks. Presence or absence of anterior loops (AL) of the inferior alveolar nerve (IAN) was determined, and the mesial extent of the loop was measured. Additional measurements included height (G‐H), width (G‐W), thickness (G‐T), and volume (G‐V) of monocortical onlay grafts harvested from the mandibular symphysis area, and thickness of the lateral wall (T‐LW) of the maxillary sinus. The independent samples t test, and a two‐tailed t test with equal variance were utilized to determine statistical significance to a level of P <0.05. Multiple regression analyses were performed to determine if each one of these measurements was affected by age and gender.

Results: The most common location of the MF in relation to teeth was found to be below the apices of mandibular premolars. The mean MF‐H was 3.47 ± 0.71 mm and the mean MF‐W was 3.59 ± 0.8 mm. The mean distance from the MF to other anatomical landmarks were: MF‐CEJ = 15.52 ± 2.37 mm, MF to the most apical portion of the lower cortex of the mandible = 12.0 ± 1.67 mm, MF to the midline = 27.61 ± 2.29 mm, and MF‐MF = 55.23 ± 5.34 mm. A high prevalence of AL was found (88%); symmetric occurrence was a common finding (76.2%), with a mean length of 4.13 ± 2.04 mm. The mean size of symphyseal grafts was: G‐H = 9.45 ± 1.08 mm, G‐W = 14.5 ± 3.0 mm, and G‐T = 6.15 ± 1.04 mm, with an average G‐V of 857.55 ± 283.97 mm3 (range: 352 to 1,200 mm3). The mean T‐LW of the maxillary sinus was 0.91 ± 0.43 mm.

Conclusion: Implant‐related anatomy must be carefully evaluated before treatment due to considerable variations among individuals, in order to prevent injury to surrounding anatomical structures and possible damage. J Periodontol 2004;75:1061‐1067.
Occurrence of Porphyromonas gingivalis and Tannerella forsythensis in Periodontally Diseased and Healthy Subjects
Authors: Yang Hui‐Wen , Huang Yu‐Feng , Chou Ming‐Yung
Published: February 2005

Background: The purpose of this study was to compare the prevalence and level of Porphyromonas gingivalis (P. gingivalis) and Tannerella forsythensis (T. forsythensis) in subgingival plaque samples from both healthy individuals and periodontal patients in different age groups.

Methods: A total of 498 subgingival plaque samples were studied. These samples were collected from 407 individuals diagnosed with periodontal disease (210 adult periodontitis [AP], 78 rapidly progressive periodontitis [RPP], and 119 refractory periodontitis [Ref‐P] cases) and 91 healthy (H) subjects. P. gingivalis and T. forsythensis were detected by indirect immunofluorescent assay using species‐specific polyclonal antisera to P. gingivalis strain (FDC 381) and T. forsythensis strain (FDC 335). The prevalence of P. gingivalis and T. forsythensis was compared by chi‐square analysis. Differences in P. gingivalis and T. forsythensis levels among various periodontal status and age groups was determined by one‐way analysis of variance and Fisher's multiple comparison tests. The association between the presence of P. gingivalis or T. forsythensis in different periodontal status and age groups was measured using odds ratios.

Results:P. gingivalis was found in 85.7% (P <0.0001) and T. forsythensis in 60.7% (P = 0.0002) of diseased subjects compared to 23.1% and 39.6%, respectively, in healthy subjects. P. gingivalis, but not T. forsythensis, was detected more frequently in any diseased group than in the H group in every age group (P <0.0001). No significant difference was found in the prevalence of P. gingivalis and T. forsythensis among age groups, except T. forsythensis was more prevalent in the age group of 40 to 59 years than in the age group <20 years (X2 = 3.93, P = 0.047) in the H group. The mean level of P. gingivalis and T. forsythensis was significantly higher in diseased groups than in the H group (P <0.0001). The odds ratio for P. gingivalis in the AP group (25.0) was greater than any other group for P. gingivalis or T. forsythensis compared to the H group.

Conclusions: These data suggested that P. gingivalis is closely associated with the pathogenesis of periodontitis and that it may not be a normal inhabitant of periodontally healthy subjects. T. forsythensis is also important in the pathogenesis of periodontal disease; however, whether it causes periodontal disease or is a secondary invader of periodontal lesions remains to be determined. J Periodontol 2004;75: 1077‐1083.
Polymorphisms in the Vitamin D Receptor Gene Are Associated With Periodontal Disease
Authors: de Brito Junior Rui Barbosa , Scarel‐Caminaga Raquel Mantuaneli , Trevilatto Paula Cristina , Souza Ana Paula , Barros Silvana Pereira
Published: February 2005

Background: Genetic polymorphisms in the vitamin D receptor (VDR) gene are associated with bone homeostasis and diseases in which bone loss is a cardinal sign. The aim of this study was to determine whether chronic periodontal disease in a Brazilian population is associated with polymorphisms in the VDR gene.

Methods: Clinical examination and recordings of probing depth and clinical attachment level were performed in 113 unrelated adults who were divided into two groups: 44 healthy individuals (control group) and 69 subjects with chronic periodontitis (CP). DNA was obtained from the subjects' epithelial cells by scraping the buccal mucosa. Two polymorphisms in the VDR gene were analyzed by polymerase chain reaction, followed by TaqI and BsmI restriction endonuclease digestion.

Results: Frequencies of VDR/TaqI and VDR/BsmI showed significant differences between the control group and the CP group (P <0.05). The “Tb” haplotype was prevalent in the control group (43.2%), and the “TB” haplotype in the CP group (36.6%). The “TB” haplotype seemed to increase susceptibility to periodontal disease (odds ratio [OR] = 2.19). The heterozygous haplotype “TB/tb” was predominant in the CP group (OR = 4.32; P = 0.005).

Conclusions:TaqI and BsmI polymorphisms of the VDR gene are associated with clinical attachment loss due to periodontal disease in a Brazilian population. These findings suggest that VDR genotype might be a risk indicator for susceptibility to chronic periodontitis. J Periodontol 2004;75:1090‐1095.
Osseointegration in a Sinus Augmented With Bovine Porous Bone Mineral: Histological Results in an Implant Retrieved 4 Years After Insertion. A Case Report
Authors: Scarano Antonio , Pecora Gabriele , Piattelli Maurizio , Piattelli Adriano
Published: February 2005

Background: A subject of controversy in implant dentistry is what is the most appropriate material for sinus augmentation. Little is known about the healing pattern and the osseointegration processes at the interface of implants placed in different grafting materials in man. Bovine porous bone mineral (BPBM) is a xenogenic material similar to human cancellous bone with a high biocompatibility and osteoconductivity.

Methods: A 50‐year‐old patient presented a posterior left maxilla with an insufficient bone height for implant insertion. In January 1999, a sinus lifting procedure was performed and the left sinus was augmented with BPBM; in November 1999, three implants were inserted, and in July 2000 a fixed prosthetic restoration was positioned. In June 2003 the connecting screw of the middle implant fractured and it was decided to remove the implant using a 5 mm trephine bur.

Results: All BPBM particles were surrounded by newly formed bone. No BPBM particle was in direct contact with the implant surface, and between the implant surface and the particles there was newlyformed bone. BPBM seemed to undergo a very slow resorption; the particles constituted 36% ± 3% of the peri‐implant tissues. The bone‐implant contact percentage was 72% ± 4%.

Conclusions: In our specimens, we found an intimate, direct contact between bone and implant without an interposition of the graft material particles. A very high bone‐to‐implant contact percentage was present. Our results show that the slow resorption of the graft particles did not jeopardize the osseointegration of the implant. J Periodontol 2004;75:1161‐1166.
A Randomized Clinical Trial Comparing Enamel Matrix Derivative and Membrane Treatment of Buccal Class II Furcation Involvement in Mandibular Molars. Part II: Secondary Outcomes
Authors: Meyle Jörg , Gonzales José R. , Bödeker Rolf H. , Hoffmann Thomas , Richter Steffen , Heinz Bernd , Arjomand Mehrdad , Reich Elmar , Sculean Anton , Jepsen Karin , Jepsen Søren
Published: February 2005

Background: This multicenter, randomized trial compared enamel matrix derivative (EMD) with barrier membranes for the treatment of Class II mandibular furcations with regard to secondary outcomes. The influence of furcation morphology on the effectiveness of either treatment was also evaluated.

Methods: Forty‐eight patients (age range 28 to 73 years; 22 females, 26 males) with buccal Class II furcation involvements in both contralateral lower first or second molars were included. After initial periodontal treatment, defects were randomized to either EMD or bioabsorbable guided tissue regeneration (GTR) barrier. Study design and the results for the primary parameter were previously described. Results of the following secondary outcome variables are reported here: changes of the hard tissue boundaries describing the anatomical situation of the furcation defect and changes in the following clinical parameters between baseline and 14 months: plaque, level of gingival margin, probing depth, bleeding on probing, attachment level, and bone sounding at five sites/tooth at the buccal side. Descriptive statistics were applied for changes in clinical parameters and measurements of hard tissue boundaries. The differences observed under treatment with EMD or membrane were analyzed by means of the Wilcoxon two‐sample test. The difference between the effect of the EMD and membrane treatment was estimated by means of the Hodges‐Lehmann estimator.

Results: Overall, similar healing results were observed for both treatments. However, there was slightly more recession in the mid‐furcation site following membrane treatment (P = 0.04). Additionally, different treatment effects could be detected for the distances from the stent or cemento‐enamel junction (CEJ) to the buccal bone crest, mid‐distal root (P stent = 0.01; PCEJ = 0.07) and for the distance from the stent or CEJ to the buccal bone crest, mid‐mesial root (P stent = 0.01; PCEJ = 0.01). There was no measurable bone resorption in EMD sites, whereas a slight resorption occurred with membrane treatment. Furcation morphology at the time of surgery was not associated with clinical outcome, irrespective of the treatment.

Conclusion: With regard to secondary outcome parameters, enamel matrix derivative treatment led to a similar regenerative result as the membrane procedure. J Periodontol 2004;75:1188‐1195.
Relative Proportions of T‐Cell Subpopulations and Cytokines That Mediate and Regulate the Adaptive Immune Response in Patients With Aggressive Periodontitis
Authors: Suárez Lina J. , Ocampo Ana M. , Dueñas Ricardo E. , Rodríguez Adriana
Published: February 2005

Background: Both the virulence factors of periodontopathic bacteria and the immune response against them have been involved in tissue destruction observed in periodontal disease. Considering the regulatory role of cytokines produced by T cells, the purpose of this study was to compare the CD3+, CD4+, and CD8+ subpopulations of T cells, and to characterize the mRNA of cytokines involved in the adaptive immune response in a group of healthy/gingivitis 1 (HI/G1) individuals and aggressive periodontitis (AgP) patients.

Methods: The percentages of T‐cell subpopulations were analyzed in 10 gingival samples of HI/G1 individuals and 10 gingival samples of AgP patients by immunohistochemistry. The presence of interleukin (IL)‐2, interferon (IFN)‐γ, IL‐4, IL‐5, IL‐10, IL‐13, and transforming growth factor (TGF)‐β was measured by reverse transcription polymerase chain reaction (RT‐PCR) of mRNA extracted from complete gingival biopsies.

Results: Significant differences were found in CD3+ and CD4+ cell counts between both groups. The parameters were lower in the gingival biopsies from AgP patients while CD8+ counts were similar in both groups. The cytokine mRNA analysis showed constant expression of IL‐2 and IFN‐γ in all cases. The mRNA of IL‐5 and IL‐10 was present in the majority of HI/G1 (N = 10, N = 9, respectively) but was not in the AgP group (N = 2, N = 1). IL‐13 and TGF‐β were only detected in HI/G1 (N = 2, N = 3) and IL‐4 was not detected in any of the individuals.

Conclusions: These results indicate that the role of the CD8+ subpopulation in aggressive periodontitis lesions is limited. On the other hand, cytokines IL‐2 and IFN‐γ may not be relevant in the progression of aggressive periodontitis. J Periodontol 2004;75: 1209‐1215.
Locally Applied Isosorbide Decreases Bone Resorption in Experimental Periodontitis in Rats
Authors: Leitão R.F.C. , Rocha F.A.C. , Chaves H.V. , Lima V. , Cunha F.Q. , Ribeiro R.A. , Brito G.A.C.
Published: February 2005

Background: The role of nitric oxide (NO) on bone metabolism is controversial, since it can either stimulate bone formation or resorption. We investigated the effect of local administration of the NO donor isosorbide in an experimental periodontal disease model.

Methods: Wistar rats were subjected to a ligature placement around the cervix of the right second upper molar and were sacrificed after 11 days. Alveolar bone loss was measured in one quadrant as the sum of the distances between the cuspid tip and the alveolar bone along the axis of each molar root, which was subtracted from the contralateral side, used as unligated control. The semiquantitative histopathological scale of the periodontium was based on cell infiltration and alveolar bone and cementum integrity. Groups were treated with a gel containing 1% or 5% isosorbide applied to the vestibular side of the molar gingiva 1 hour before the placement of the ligature and then twice daily until sacrifice. Controls included one group subjected to periodontitis and no treatment (NT) and another that received the gel containing just the vehicle (V).

Results: The application of the vehicle gel produced an increase of the alveolar bone resorption, without altering the inflammatory changes, compared to the NT group. The 5% isosorbide produced a significant reduction of the alveolar bone resorption, compared to V and NT. This reduction was confirmed by histological analysis, showing less inflammatory cell infiltration and preservation of the cementum and the alveolar process.

Conclusion: Local application of isosorbide reduces alveolar bone resorption in experimental periodontal disease in rats, suggesting a local anti‐inflammatory effect of isosorbide. J Periodontol 2004;75:1227‐1232.
Effects of Implant Thread Geometry on Percentage of Osseointegration and Resistance to Reverse Torque in the Tibia of Rabbits
Authors: Steigenga Jennifer , Al‐Shammari Khalaf , Misch Carl , Nociti Francisco H. , Wang Hom‐Lay
Published: February 2005

Background: Dental implant thread geometry has been proposed as a potential factor affecting implant stability and the percentage of osseointegration. Therefore, the aim of this prospective, randomized, parallel arm study was to evaluate the effects of dental implant thread design on the quality and percent of osseointegration and resistance to reverse torque in the tibia of rabbits.

Methods: Seventy‐two custom‐made, screw‐shaped, commercially pure titanium implants (3.25 mm diameter × 7 mm length) were placed in the tibiae of 12 white New Zealand rabbits. Each tibia received three implants of varying thread shapes: one with a Vshaped, one with a reverse buttress, and one with a square thread design. The rabbits were sacrificed following an uneventful healing period of 12 weeks. Implants in the right tibiae underwent histologic and histomorphometric assessments of the bone‐to‐implant contact (BIC) and the radiographic density of surrounding bone, while implants in the left tibiae were used for reverse‐torque testing. Differences between the three thread designs were examined using analysis of variance (ANOVA).

Results: Data showed that the square thread design implants had significantly more BIC and greater reverse‐torque measurements compared to the V‐shaped and reverse buttress thread designs, while no differences were found in radiographic bone density assessments.

Conclusion: These results indicate that the square thread design may be more effective for use in endosseous dental implant systems. J Periodontol 2004;75:1233‐1241.
Further Evidence of the Association Between Periodontal Conditions and Coronary Artery Disease
Authors: Geerts Sabine O. , Legrand Victor , Charpentier Joseph , Albert Adelin , Rompen Eric H.
Published: February 2005

Background: There is increasing evidence that chronic infections, such as periodontal diseases, could play a role in the initiation and development of coronary artery disease (CAD). The present study was intended to test for a possible association between presence and severity of periodontitis and coronary artery disease in a Belgian population.

Methods: A total of 108 CAD patients (mean age 59.2 ± 11 years) and 62 presumably healthy controls (mean age 57.7 ± 9 years) were enrolled in the study. Probing depth, periodontal pocket bleeding index (PPBI), plaque index, furcation involvements, and tooth mobility were evaluated to compare periodontal health in both groups. The subjects were also ranked according to a novel index of periodontitis severity, the periodontal index for risk of infectiousness (PIRI), aimed at quantifying the risk of release of proinflammatory mediators from the periodontal sites.

Results: Periodontitis was significantly more frequent in CAD patients than in controls (CAD patients: 91%; controls: 66%). The mean number of pockets was 18 ± 17.1 in cardiac patients versus 7.6 ± 12.7 in controls (P <0.0001), despite the fact that the mean number of missing teeth was significantly greater in cases than in controls (14 ± 7.1 versus 9 ± 5.2; P <0.0001). Furthermore, proportions of mobile teeth, bleeding sites, periodontal pockets, and involved furcations were significantly higher in CAD patients than in controls. In addition, the extent of the periodontal disease present was also greater in cases than in controls. A logistic model, adjusted for known cardiovascular risk factors, showed a strong association between CAD and periodontitis (odds ratio [OR] = 6.5). Moreover, there was a significant dose‐response relationship between increasing scores of the periodontal risk of infectiousness and the presence of CAD (adjusted OR = 1.3 per PIRI unit).

Conclusion: In the present study, periodontitis was revealed to be a significant risk factor for CAD after adjusting for other confounding factors, with the level of association increasing with the individual extent of the periodontal lesions. J Periodontol 2004;75:1274‐1280.
Enhancement of Periodontal Tissue Regeneration by Transplantation of Bone Marrow Mesenchymal Stem Cells
Authors: Kawaguchi Hiroyuki , Hirachi Akio , Hasegawa Naohiko , Iwata Tomoyuki , Hamaguchi Hidenori , Shiba Hideki , Takata Takashi , Kato Yukio , Kurihara Hidemi
Published: February 2005

Background: The use of suitable cells transplanted into periodontal osseous defects appears to be a powerful strategy to promote periodontal tissue regeneration. Mesenchymal stem cells (MSCs) isolated from bone marrow have the potential for multilineage differentiation. The purpose of this study was to examine whether auto‐transplantation of MSCs into periodontal osseous defects would be useful for periodontal tissue regeneration.

Methods: Bone marrow MSCs were isolated from beagle dogs and expanded in vitro. The expanded MSCs were mixed with atelocollagen (2% type I collagen) at final concentrations of 2 × 106, 5 × 106, 1 × 107, or 2 × 107 cells/ml, and auto‐transplanted into experimental Class III defects. Atelocollagen alone was implanted into the defects as a control. Periodontal tissue healing was evaluated by histological and morphometric analyses 1 month after transplantation.

Results: The defects were regenerated with cementum, periodontal ligament, and alveolar bone in the MSC‐atelocollagen groups. Less periodontal tissue regeneration was observed in the control group compared to the MSC‐atelocollagen groups. Morphometric analysis revealed that the percentage of new cementum length in the 5 × 106 and 2 × 107 cells/ml groups and the percentage of new bone area in the 2 × 107 cells/ml group were significantly higher than in the control group (P <0.01).

Conclusion: These findings suggest that auto‐transplantation of bone marrow mesenchymal stem cells is a novel option for periodontal tissue regeneration. J Periodontol 2004;75:1281‐1287.
Thermal stability, structural features, and B‐to‐Z transition in DNA tetraloop hairpins as determined by optical spectroscopy in d(CG)3T4(CG)3 and d(CG)3A4(CG)3 oligodeoxynucleotides
Authors: Hernández Belén , Baumruk Vladimir , Gouyette Catherine , Ghomi Mahmoud
Published: February 2005

NMR and CD data have previously shown the formation of the T4 tetraloop hairpin in aqueous solutions, as well as the possibility of the B‐to‐Z transition in its stem in high salt concentration conditions. It has been shown that the stem B‐to‐Z transition in T4 hairpins leads to S (south)‐ to N (north)‐type conformational changes in the loop sugars, as well as anti to syn orientations in the loop bases. In this article, we have compared by means of UV absorption, CD, Raman, and Fourier transform infrared (FTIR), the thermodynamic and structural properties of the T4 and A4 tetraloop hairpins formed in 5′‐d(CGCGCG‐TTTT‐CGCGCG)‐3′ and 5′‐d(CGCGCG‐AAAA‐CGCGCG)‐3′, respectively. In presence of 5M NaClO4, a complete B‐to‐Z transition of the stems is first proved by CD spectra. UV melting profiles are consistent with a higher thermal stability of the T4 hairpin compared to the A4 hairpin. Order‐to‐disorder transition of both hairpins has also been analyzed by means of Raman spectra recorded as a function of temperature. A clear Z‐to‐B transition of the stem has been confirmed in the T4 hairpin, and not in the A4 hairpin. With a right‐handed stem, Raman and FTIR spectra have confirmed the C2′‐endo/anti conformation for all the T4 loop nucleosides. With a left‐handed stem, a part of the T4 loop sugars adopt a N‐type (C3′‐endo) conformation, and the C3′‐endo/syn conformation seems to be the preferred one for the dA residues involved in the A4 tetraloop. © 2005 Wiley Periodicals, Inc. Biopolymers 78: 21–34, 2005
Kefir yeast technology: Scale‐up in SCP production using milk whey
Authors: Koutinas A.A. , Athanasiadis I. , Bekatorou A. , Iconomopoulou M. , Blekas G.
Published: February 2005

A three‐step process to scale‐up kefir biomass production at a semi‐industrial scale employing whey is reported. Aerobic fermentations were initially performed at laboratory scales, in 1.5‐ and 4‐L bioreactors, yielding 79 g/L final kefir biomass (0.89 g/g of lactose utilized), in 7 h of fermentation time. The use of whey as carbon source even in solid cultures led to the formation of a granular biomass. These results encouraged scale‐up at a semi‐industrial‐scale pilot plant employing 100‐ and 3,000‐L bioreactors, leading to the development of a process for granular kefir biomass production. The results validated the laboratory‐scale experiments and the avoidance of centrifugal separators due to granular biomass formation. Pilot‐plant operations showed kefir to be highly resistant to contamination under actual industrial conditions and no serious problems in handling of raw materials and equipment were observed. Economic analysis showed a 20% higher cost of the market price of products, with added value of up to 15.9 × 109 € within the European Union. © 2005 Wiley Periodicals, Inc.
Exploration of the Lithium—Aluminum—Silver System. Crystal and Electronic Structure Analysis of New Phases Li6.98Al4.15Ag0.87 and LiAlAg2.
Authors: Lacroix‐Orio Laurence , Tillard Monique , Belin Claude
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.
Structural—Magnetic Properties Relationship in a New Commensurate Material: Sr9Mn5Co2O21.
Authors: Boulahya K. , Parras M. , Gonzalez‐Calbet J. M. , Martinez J. L.
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.
Phase Equilibria in the Ag—Dy—Sb System at 400 °C.
Authors: Zeng Lingmin , Xie Xinyun
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.
Preparation and Characterization of Dimercury(I) Monofluorophosphate(V), Hg2PO3F: Crystal Structure, Thermal Behavior, Vibrational Spectra, and Solid‐State 31P and 19F NMR Spectra.
Authors: Weil Matthias , Puchberger Michael , Baran Enrique J.
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.
[N(CH2CH2NH3)3] [U3O2F13]×2H2O: A Novel Organically Templated Mixed‐Valent Uranium Oxyfluoride with a Hybrid Network Structure.
Authors: Wang Chih‐Min , Liao Chia‐Hsien , Lin Hsiu‐Mei , Lii Kwang‐Hwa
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.
A Mixed Cation Nickel Diphosphate with a Layered Intergrowth Structure: Synthesis, Structural and Magnetic Characterization of Na(NH4) [Ni3(P2O7)2 (H2O)2].
Authors: Liu Wei , Yang Xin Xin , Chen Hao Hong , Huang Ya Xi , Schnelle Walter , Zhao Jing Tai
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.
tert‐Amino Effect in Heterocyclic Chemistry. Synthesis of Hydrogenated Spiro Derivatives of Quinolines.
Authors: D'yachenko E. V. , Glukhareva T. V. , Nikolaenko E. F. , Tkachev A. V. , Morzherin Yu. Yu.
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.
Reactions of Alkyl 2‐Benzylidene‐2‐polyfluoroacylacetates with N,N‐Dinucleophiles.
Authors: Pryadeina M. V. , Burgart Ya. V. , Kodess M. I. , Saloutin V. I. , Chupakhin O. N.
Published: February 2005

For Abstract see ChemInform Abstract in Full Text.