bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immediate Implantation in Fresh Extraction Sockets. A Controlled Clinical and Histological Study in Man
Authors: Paolantonio Michele , Dolci Marco , Scarano Antonio , D'Archivio Domenico , Di Placido Giacinto , Tumini Vincenzo , Piattelli Adriano 
Published: February 2005

Background: Early implantation may preserve the alveolar anatomy, and the placement of a fixture in a fresh extraction socket helps to maintain the bony crest. Although a number of clinical studies exist, no histological reports show the outcome of implantation in fresh extraction sockets without the use of membranes in humans compared to implants placed in mature bone.Methods: Forty‐eight healthy patients, receiving at least 4 fixtures in each of 2 symmetrical quadrants, underwent placement of 1 experimental fixture placed in a fresh extraction socket (TI) and 1 contralateral fixture in mature bone (CI). TI were placed after atraumatical tooth extraction, with a surgical site at the apex of the socket and a tight contact between the fixture and the socket's walls, but without the use of filling materials or membranes. The flap was coronally repositioned to obtain primary wound closure. Immediately after surgical intervention, a standardized periapical radiograph was taken. Second‐stage surgery was done after 6 months. Six months after the second surgery, a second standardized periapical radiograph was taken and clinical parameters (bleeding and plaque index) recorded. Marginal bone loss (MBL) from the time of implant placement to the time of fixture removal was calculated by comparing periapical radiographs. TI and CI were then removed by a hollow drill to obtain histological specimens. Non‐demineralized sections were stained by acid fuchsin and toluidine blue, and by von Kossa to evaluate the degree of bone mineralization. The percentage of direct implant‐bone contact (DBC) was calculated by a computerized microscopic digitizer.Results: No significant differences in the clinical and radiographic parameters were observed between the 2 experimental categories. There was no statistically significant difference between TI and CI for DBC either in the maxilla or in the mandible. No connective or fibrous tissues were present around TI or CI. Bone resorption was not present in any of the histological sections.Conclusions: The present study shows that when a screw‐type dental implant is placed without the use of barrier membranes or other regenerative materials into a fresh extraction socket with a bone‐to‐implant gap of 2 mm or less, the clinical outcome and degree of osteointegration does not differ from implants placed in healed, mature bone. J Periodontol 2001;72:1560‐1571.
A Comparison of Porous and Non‐Porous Teflon Membranes Plus Demineralized Freeze‐Dried Bone Allograft in the Treatment of Class II Buccal/Lingual Furcation Defects: A Clinical Reentry Study
Authors: Lamb James W. , Greenwell Henry , Drisko Connie , Henderson Robin D. , Scheetz James P. , Rebitski George 
Published: February 2005

Background: The aim of this 9‐month reentry study was to compare the regenerative healing using porous (P) and nonporous (NP) teflon barrier membranes plus demineralized freeze dried bone allografts (DFDBA) in Class II buccal/lingual furcation defects.Methods: Twenty‐four patients, 13 males and 11 females, ages 38 to 75 (mean 54 ± 10), were included in this study. Each patient had adult periodontitis and one Class II furcation defect measuring ≥3 mm open horizontal probing depth. Twelve patients were randomly selected to receive the NP treatment and 12 received the P membrane. All defects received a DFDBA graft. Measurements were performed by a masked examiner.Results: No statistically significant differences (P >0.05) were found between NP and P groups at any time with respect to any open or closed measure. Improvement in mean open horizontal probing depth was significant for both the NP (2.33 ± 0.78 mm) and P (2.75 ± 0.75 mm) groups. Mean clinical attachment level gains at 9 months were significant for both NP (1.50 ± 1.62 mm) and P (2.50 ± 2.11 mm) groups. Seventeen of 24 defects had an intrabony component and ≥50% fill was obtained in 100% of these defects.Conclusions: The results of this 9‐month reentry study comparing the use of porous and non‐porous barrier membranes with a DFDBA graft indicate that there were no statistically significant differences between groups. Both groups showed a statistically significant improvement following the treatment of Class II furcation defects in humans. J Periodontol 2001;72:1580‐1587.
Tetracycline Modulates Collagen Membrane Degradation In Vitro
Authors: Moses Ofer , Nemcovsky Carlos E , Tal Haim , Zohar Ron 
Published: February 2005

Background: Structural integrity of implanted bioabsorbable barrier membranes should be preserved for a sufficient time to ensure expected results. Collagen membranes are degraded by metalloproteinases (MMP). Their degradation rate can be altered either by enhancing structural integrity or by delaying the degradation process using MMP inhibitors. Tetracyclines (TTC) present inhibitory effects on matrix MMP. Immersing membranes in TTC solution before implantation can delay their degradation. The purpose of the present study was to evaluate the effect of collagen membranes immersed in varying TTC concentration solutions on the rate of their degradation in vitro.Methods: Collagen bioabsorbable membranes were prepared as 5 mm diameter membrane discs. Membranes were then incubated at 4°C for 24 hours, in either phosphate buffered saline (PBS, Ca2 + and Mg2 + free) or with TTC‐HCl dissolved in PBS concentrations of 5 mg/ml, 50 mg/ml or 100 mg/ml. After rinsing, membranes were incubated with either bacterial collagenase or cultures of human bone lineage cells. Membrane degradation was studied on days 2, 4, 7, and 14. Two‐ and 3‐way analysis of variance was used to analyze results.Results: Samples supplemented with bacterial collagenase exhibited a statistically significant interaction between changes of free protein in the medium, antibiotic concentration used for the immersion, presence of collagenase in the medium, and incubation time (P <0.0001). Membranes incubated with bone cells exhibited similar degradation trends.Conclusions: Collagen membranes immersed in 50 mg/ml TTC solution exhibited the longest degradation time, both in the clostridial collagenase and the human bone cell lineage assays. Immersion in a 50 mg/ml TTC solution before implantation will delay their degradation. J Periodontol 2001;72:1588‐1593.
Activation of Matrix Metalloproteinase‐2 by a Novel Oral Spirochetal Species Treponema lecithinolyticum
Authors: Choi Bong‐Kyu , Jung Jung‐Hag , Suh Hye‐Yuhn , Yoo Yun‐Jung , Cho Kyoo‐Sung , Chai Jung‐Kiu , Kim Chong‐Kwan 
Published: February 2005

Background: Periodontal tissue destruction is a characteristic of periodontitis. This can be caused by either bacterial enzymes or host cell‐derived matrix metalloproteinases (MMPs). In order to elucidate the etiologic role of oral spirochetes, we investigated the effects of Treponema lecithinolyticum, a novel saccharolytic species, on MMP‐2 activation.Methods: Gingival fibroblasts (GFs) and periodontal ligament (PDL) cells obtained from healthy human subjects were cultured to confluence in α‐minimal essential medium (α‐MEM) supplemented with 10% fetal bovine serum. After serum starvation for a day, the cultures were treated with whole cell sonicates, heat‐denatured whole cell sonicates, outer membrane fraction (OMF) or formaldehyde‐fixed cells of T. lecithinolyticum. Culture supernatants were collected after incubation for 24 to 48 hours and analyzed for MMP‐2 activation by gelatin zymography. Collagenolytic activity was quantitatively measured using human [3H] type IV collagen as a substrate.Results: Treatment of GFs and PDL cells with whole cell sonicates, formaldehyde‐fixed whole cells, or the OMF of T. lecithinolyticum resulted in the production of MMP‐2 partly in the fully active form with a molecular mass of 62 kDa, whereas nontreated control cultures and cultures treated with a heat‐denatured fraction did not show the active form. Cultures exposed to T. lecithinolyticum had higher collagenolytic activity than non‐treated cultures.Conclusions: Our results demonstrate that T. lecithinolyticum, possibly mediated by proteinaceous cell surface‐associated components, may participate in extracellular matrix degradation by activation of MMP‐2 during periodontal inflammation. J Periodontol 2001;72:1594‐1600.
Effect of Avocado and Soybean Unsaponifiables on Gelatinase A (MMP‐2), Stromelysin 1 (MMP‐3), and Tissue Inhibitors of Matrix Metalloproteinase (TIMP‐1 and TIMP‐2) Secretion by Human Fibroblasts in Culture
Authors: Kut‐Lasserre C. , Miller C. Chaussain , Ejeil A.L. , Gogly B. , Dridi M. , Piccardi N. , Guillou B. , Pellat B. , Godeau G. 
Published: February 2005

Background: In inflamed periodontal tissues, gingival fibroblasts are able to express matrix metalloproteinases (MMPs) and their natural inhibitors, tissue inhibitors of matrix metalloproteinases (TIMPs). They can also respond to growth factors and cytokines. In this study, the in vitro effects of avocado and soybean unsaponifiable residues (ASU), their fractions (avocado unsaponifiable [ASF] or soy unsaponifiable [SSF]) on MMP‐2 and MMP‐3, and the activity and secretion of their inhibitors TIMP‐1 and TIMP‐2 were investigated using cultured human gingival fibroblasts.Methods: Gingival fibroblasts were cultured for 72 hours with ASU, ASF, and SSF at concentrations of 0.1, 0.5, 2.5, 5, and 10 μg/ml of culture medium, after pretreatment or no pretreatment for 1 hour with interleukin‐1β (IL‐1β). MMP‐2 and MMP‐3 were detected and quantified in the culture media after zymography and image analysis. TIMP‐1, TIMP‐2, MMP‐2, and MMP‐3 were also evidenced by dot blotting and quantified by image analysis.Results: In the absence of IL‐1β, a slight decrease in the secretion of MMP‐2 was observed with lower doses of ASU, ASF, and SSF. The decrease of MMP‐3 secretion was clearly marked with all fractions especially at low concentrations (0.1 and 2.5 μg/ml). A slight decrease in TIMP‐2 secretion was seen for low doses of ASU, ASF, and SSF, while a small increase was seen at higher concentrations. Concerning TIMP‐1, no significant variation was observed in culture medium for low concentrations, and a decrease was noted for 5 and 10 μg/ml of ASU, ASF, and SSF. As anticipated, IL‐1β induced a marked release of MMP‐2, MMP‐3, and TIMP‐1, but no variation for TIMP‐2 was seen. ASU, ASF, and SSF reversed the IL‐1β effect on gingival fibroblasts for MMP‐2 and MMP‐3, particularly with doses varying from 0.1 to 2.5 μg/ml and for TIMP‐1, particularly with doses varying from 2.5 to 10 μg/ml.Conclusions: These findings suggest a potential role for avocado and soy unsaponifiable extracts to prevent the deleterious effects of IL‐1β that occur during periodontal diseases. J Periodontol 2001;72:1685‐1694.
Treatment of Intrabony Defects With Enamel Matrix Proteins or Bioabsorbable Membranes. A 4‐Year Follow‐Up Split‐Mouth Study
Authors: Sculean Anton , Donos Nikolaos , Miliauskaite Asta , Arweiler Nicole , Brecx Michel 
Published: February 2005

Background: Treatment with enamel matrix proteins (EMD) and guided tissue regeneration (GTR) with bioabsorbable membranes has been shown to promote periodontal regeneration; however, until now, there were only limited data on the long‐term clinical results following these regenerative techniques. Therefore, the aim of the present study was to present the 4‐year results following treatment of intrabony defects with EMD or guided tissue regeneration (GTR).Methods: Twelve patients, each displaying one pair of intrabony defects located contralaterally in the same jaw, were randomly treated with EMD or with GTR by means of bioabsorbable membranes. The following clinical parameters were evaluated at baseline, at 1 year, and at 4 years after treatment: plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL). The primary outcome variable was CAL. No statistically significant differences between the groups were found at baseline. Power analysis to determine superiority of EMD treatment showed that the available sample size would yield 70% power to detect a 1 mm difference.Results: The sites treated with EMD demonstrated mean CAL change from 9.8 ± 2.0 mm to 6.4 ± 1.6 mm (P <0.001) and to 6.8 ± 1.8 mm (P <0.001) at 1 and 4 years, respectively. No statistically significant differences were found between the CAL mean at 1 and 4 years postoperatively. The sites treated with GTR showed a mean CAL change from 9.8 ± 2.3 mm to 6.6 ± 1.7 mm (P <0.001) at 1 year and to 6.9 ± 1.8 mm (P <0.001) at 4 years. The CAL change between 1 and 4 years did not present statistically significant differences. No statistically significant differences in any of the investigated parameters were observed at 1 and 4 years between the treatment groups.Conclusions: It was concluded that the CAL gain obtained following treatment with EMD or GTR can be maintained over a 4‐year period. J Periodontol 2001;72:1695‐1701.
Histologic and Radiographic Evidence of Vertical Ridge Augmentation Utilizing Distraction Osteogenesis: 10 Consecutively Placed Distractors
Authors: McAllister Bradley S. 
Published: February 2005

Background: Vertical ridge augmentation for dental implant placement is one of the greatest challenges facing the surgeon. Inadequate vertical bone compromises the implant positioning and resulting restoration. The cleansibility, esthetics, and mechanical properties of the restoration can all be compromised. While the technique of distraction osteogenesis has been successfully employed for long bone applications for over 40 years, it has only recently been introduced as a technique for vertical ridge augmentation prior to dental implant reconstruction.Methods: In this study, the placement of 10 consecutive distractors in 7 patients was evaluated. The surgical technique, latency period, distraction rate, and consolidation period are reviewed.Results: The technique of distraction osteogenesis resulted in an average vertical augmentation of 7 mm, with a range of 5 to 9 mm. There were no complications affecting the outcome of the distraction procedure. No failures have occurred to date in the 16 implants that were placed and loaded following distraction.Conclusions: In summary, clinical, histologic, and radiographic evidence of consistent vertical bone augmentation was found with this technique of distraction osteogenesis for vertical ridge augmentation. J Periodontol 2001;72:1767‐1779.
Intra‐ and Inter‐Examiner Reproducibility in Keratinized Tissue Width Assessment With 3 Methods for Mucogingival Junction Determination
Authors: Guglielmoni Paola , Promsudthi Ananya , Tatakis Dimitris N. , Trombelli Leonardo 
Published: February 2005

Background: Although the need for “adequate” amount of keratinized tissue (KT) for periodontal health is questionable, the mucogingival junction (MGJ) often serves as a measurement landmark in periodontal evaluations. Limited information is available on the reproducibility of KT width (KTW) assessment. The purpose of this study was to assess intra‐ and inter‐examiner reproducibility in measuring KTW by using 3 different methods to identify MGJ location.Methods: Fifteen patients provided 17 teeth which had undergone a gingival augmentation procedure (connective tissue graft; surgery group) and an equal number of contralateral, non‐treated teeth (control group). At the midbuccal aspect of each tooth, KTW was assessed by 2 independent examiners after MGJ identification by the visual (VM), functional (FM), and visual with histochemical staining (HM) method. Data analysis was based on intra‐class correlation coefficients (ICC) and 3‐way analysis of variance (ANOVA) for differences between replicate measurements.Results: KTW was significantly different between treated and control teeth. No significant differences in KTW were found in relation to method for MGJ determination and examiner. Intra‐ and inter‐examiner reproducibility was high, regardless of treatment status or method for MGJ determination (ICC = 0.92 – 0.99). Standard deviations of the difference between replicate measurements ranged from 0.46 mm for VM to 0.21 mm for HM.Conclusions: Intra‐ and inter‐examiner reproducibility has been shown to be substantially consistent when different methods for MGJ determination are used to measure the apico‐coronal dimension of the gingiva. The level of reproducibility does not seem to be affected whether or not the mucogingival complex has been surgically altered by a gingival augmentation procedure. J Periodontol 2001;72:134‐139.
The Influence of Partial and Full‐Mouth Recordings on Estimates of Prevalence and Extent of Lifetime Cumulative Attachment Loss: A Study in a Population of Young Male Military Recruits
Authors: Eaton Kenneth A. , Duffy Sarah , Griffiths Gareth S. , Gilthorpe Mark S. , Johnson Newell W. 
Published: February 2005

Background: Previous studies have shown that the use of index teeth may underestimate the prevalence of chronic periodontitis in adults. However, there is little information on the effect of using index teeth to estimate the prevalence of early periodontitis in younger adults and the effect this may have on planning treatment needs and health care resources. The aim of this study was to compare full mouth examination with partial examination using index teeth in a group of young British males.Methods: One hundred subjects aged between 16 and 20 years (mean 17 years) on entry to the study were examined at baseline, 12 months later, and 30 months later. Lifetime cumulative attachment loss (LCAL) ≥1 mm was measured on the mesio‐buccal, disto‐buccal, mesio‐lingual, and disto‐lingual surfaces of all teeth, excluding third molars. All data were entered into a database. The indices used to express LCAL were prevalence, defined as the percentage of subjects with LCAL ≥1 mm, 2 mm, or 3 mm, and extent, defined as the percentage of sites with LCAL ≥1 mm, 2 mm, or 3 mm. Two sets of index teeth were chosen to compare with full mouth recordings, Ramfjord index teeth and the Periodontal Index for Treatment (PIT) teeth.Results: The prevalence of LCAL ≥1 mm was similar (approaching 100%) for the full mouth and both partial mouth recordings. However, as LCAL increased from a minimum of 1 to 3 mm, partial mouth recording resulted in an underestimation of the prevalence of disease. LCAL ≥2 mm was underestimated by up to 22% and LCAL ≥3 mm by up to 36%. The extent of LCAL was less affected by partial mouth recording, in that the percentage of sites with no sign of early attachment loss was underestimated by up to 11%. However, the percentage of sites with LCAL ≥1 mm and 2 mm were overestimated by 11% and, 7% respectively.Conclusions: These data indicate that the use of index teeth in epidemiological studies which include young adults may result in an underestimation of the prevalence of early periodontitis and an overestimation of the extent. J Periodontol 2001;72:140‐145.
Macrophages and Lymphocyte Subpopulations in Nifedipine‐ and Cyclosporin A‐Associated Human Gingival Overgrowth
Authors: Pernu Hilkka E. , Knuuttila Matti L. E. 
Published: February 2005

Background: Nifedipine and cyclosporin A (CsA) induce gingival overgrowth. Both drugs have immunomodulating effects. It has been suggested that altered immune response is associated with drug‐induced gingival overgrowth. In this study, we evaluated whether there were differences in macrophages and lymphocyte subpopulations in human nifedipine‐ and CsA‐associated gingival overgrowth as compared with those in normal gingiva.Methods: Biopsy samples of overgrown gingiva were obtained from 9 nifedipine‐treated cardiac outpatients, 13 CsA‐treated renal transplant recipients including 9 patients who were also receiving nifedipine, and 30 healthy control individuals undergoing dental treatment. Serial 5 µm thick cryostat sections were stained with mAbs for CD20 (B‐pan), CD68 (macrophages), CD4 (T‐helper/inducer), and CD8 (T‐cytotoxic/suppressor) using an avidin‐biotin‐horseradish peroxidase complex method. Numbers of mAb‐labeled and all nucleated cells were determined in 3 areas: the connective tissue beneath the sulcular epithelium, the middle connective tissue, and the connective tissue beneath the oral epithelium. Distributions of each type of cell were expressed as percentages of mAb‐labeled cells in relation to total number of nucleated cells in a counting zone. Significances of differences between groups were tested by means of the Kruskal‐Wallis test, and between pairs of results by means of the Mann‐Whitney U‐test.Results: The proportion of CD8‐labeled cells was significantly higher in connective tissue beneath the sulcular epithelium in the nifedipine group than in the controls (P = 0.014). In both medicated groups, the proportions of CD68‐labeled cells were higher in all counting zones than in the controls, but statistically significantly only in the nifedipine group in the connective tissue beneath the oral epithelium (P = 0.008). No intergroup differences were found with respect to CD4‐ and CD20‐labeled cells. The CD4/CD8 ratio was significantly lower in connective tissue beneath the sulcular epithelium in the nifedipine group than in the controls (P = 0.013).Conclusion: The results support the idea that immune response may be altered in drug‐induced gingival overgrowth. J Periodontol 2001;72: 160‐166.
Laser Irradiation of Bone: III. Long‐Term Healing Following Treatment by CO2 and Nd:YAG Lasers
Authors: McDavid Valerie G. , Cobb Charles M. , Rapley John W. , Glaros Alan G. , Spencer Paulette 
Published: February 2005

Background: Relative few reports exist concerning healing of laser created osteotomies over an extended period of time. The purpose of this study was to evaluate long‐term healing, from 21 to 63 days, of osteotomy defects in the rat tibia created with the Nd:YAG and CO2 in the presence of a surface cooling spray of air/water.Methods: The experimental model consisted of 15 large Sprague‐Dawley rats. Six treatment modalities were randomly distributed among 6 tibial recipient sites: 1) a negative control (no treatment); 2) a positive control (bur osteotomy); 3) CO2 laser at 5 W (860 J/cm2); 4) CO2 laser at 6 W (1032 J/cm2); 5) Nd:YAG laser at 5 W (714 J/cm2); and 6) Nd:YAG laser at 7 W (1000 J/cm2). All laser irradiation was delivered in the presence of a surface coolant consisting of air (15 psi) and sterile water. Five animals were sacrificed at each of 3 time intervals: 21, 35, and 63 days post‐treatment. Multiple histologic sections from each treatment site were examined by light microscopy using hematoxylin and eosin Goldner's trichrome stains, and polarized light and evaluated for presence of a char layer, heat induced cracking, heat related alterations in cells or tissue matrix, and osseous regeneration.Results: Healing was severely delayed in all laser treated sites compared to positive control sites. Of the laser treated sites, those irradiated by CO2 laser at 5 W (780 J/cm2) exhibited the greater amount of bone regeneration. At best, however, only a small percentage of sections from any of the laser treated specimens showed evidence of bone regeneration within the ablation defect regardless of the post‐treatment time interval.Conclusions: Under the conditions of this study, the osseous healing response was severely delayed by CO2 and Nd:YAG laser irradiation of bone, even in the presence of a surface cooling spray of air/water. J Periodontol 2001;72:174‐182.