bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bone‐Implant Contact on Machined and Dual Acid‐Etched Surfaces After 2 Months of Healing in the Human Maxilla
Authors: Trisi Paolo , Lazzara Richard , Rebaudi Alberto , Rao Walter , Testori Tiziano , Porter Stephan S. 
Published: February 2005

Background: Recent clinical studies indicate that an implant with a textured surface may be loaded sooner than traditional healing protocols have recommended. In a previous study, the 6‐month bone‐implant contact for dual acid‐etched and machined implant surfaces was reported to be 72.96% and 33.98%, respectively. In 1991, a minimum of 50% bone‐implant contact was considered necessary for loading to ensure long‐term survival of the implant. This study evaluated the 2‐month bone‐implant contact for dual acidetched and machined implant surfaces to determine if this criterion had been met.Methods: Custom manufactured implants (2 mm diameter and 5 mm length), having on one side a machined surface and on the other side a dual acid‐etched surface, were placed in the posterior maxilla of 11 patients, allowed to integrate for 2 months, then removed using a 4 mm internal diameter trephine with irrigation. Sections were processed and stained for histologic and histomorphometric analysis. The parameters calculated for each section were: bone volume (BV%), actual percent bone‐implant contact (BIC%), and expected bone contact (EBC%) as determined from 3 implant images superimposed onto the adjacent bone 150, 500, and 1,000 µm lateral to the actual implant surface and representing the bone‐implant contact expected on the day the implant was placed, based on the peri‐implant bone volume.Results: Histomorphometric analysis indicated that the mean BV% of 36.77% from all sections was closely matched to the mean EBC% of 34.36% (P<0.001). The analysis showed that after 2 months of healing, the 47.81% BIC% on the dual acid‐etched side was statistically higher (analysis of variance, P<0.001) than the 19.00% BIC% on the machined side. In areas of low‐density bone (<40% BV%), the difference between the BIC% for the machined and dual acid‐etched sides was even greater. Nine of the 11 dual acid‐etched sides had a higher BIC% than the EBC% value. In the machined group, 1 of the 11 sides had a higher BIC% value than the EBC% value. The bone surrounding the dual acid‐etched surface was a woven bone with thin, connecting peri‐implant bony trabeculae projecting into and between the threads. Bone on the machined side was observed mostly contacting the tips of the screw threads.Conclusions: At 2 months, the mean BIC% for the dual acid‐etched group increased 39.14% compared to the EBC% value, while the mean BIC% for the machined group decreased 44.70%. Based on the histomorphometric results of this study, sufficient bone for functional loading of the implant exists on a dual acidetched surface after 2 months of healing in the posterior maxillary arch. J Periodontol 2003;74:945‐956.
Clinical and Radiographic Evaluation of Soft and Hard Tissue Changes Around Implants: A Pilot Study
Authors: Joly Julio Cesar , de Lima Antonio Fernando Martorelli , da Silva Robert Carvalho 
Published: February 2005

Background: The aim of this study was to evaluate the clinical and radiographic changes in the peri‐implant tissues around one‐stage implants with different smooth neck portion lengths before and after functional prosthetic loading.Methods: Twelve one‐stage implants were placed in adult patients with bilateral edentulous posterior mandibular ridges. The sites were randomly assigned into two groups of six each: group 1: 2.8 mm neck implants and group 2: neck implants. The parameters plaque index (Pl), gingival index (GI), probing depth (PD), gingival margin level (GML), relative clinical attachment level (r‐CAL), and optical density (OD) were measured at loading (4 months) and 12 months after implant placement. The radiographic parameter osseous level (OL) was measured at implant placement, loading, and at 12 months. Analysis of variance and the paired Student t test were used to detect difference over time and between groups.Results: The results showed significant differences (P <0.05) for both groups for PD, r‐CAL, and OL for intragroup comparisons over time. However, no significant differences were found for Pl, GI, PD, GML, OD, and OL for between‐group comparisons.Conclusion: Bony loss occurred before loading, supporting the soft tissues and maintaining the biologic width irrespective of the smooth portion length. J Periodontol 2003;74:1097‐1103.
Evaluation of Human Recession Defects Treated with Coronally Advanced Flaps and Either Enamel Matrix Derivative or Connective Tissue. Part 2: Histological Evaluation
Authors: McGuire Michael K. , Cochran David L. 
Published: February 2005

Background: A number of surgical procedures are effective in covering denuded root surfaces. The first paper in this series evaluated the subepithelial connective tissue graft and the coronally advanced flap with enamel matrix derivative (EMD). That paper revealed no significant difference in the percent of root coverage between the two treatments (P = 0.82). There is limited human histological evidence of the type of attachment achieved with these types of procedures. This paper presents a human case report detailing the histological nature of the attachment of these two treatments to the root surfaces previously exposed by recession.Methods: One patient presented with two hopeless teeth that were randomized to receive either a subepithelial connective tissue graft or a coronally advanced flap plus EMD. The surgery was accomplished in accordance to the protocol previously described. The teeth and a small collar of tissue were removed at 6 months and underwent histological analysis.Results: Histological evaluation of the subepithelial connective tissue graft revealed a connective tissue attachment between the tooth and graft, and no histological evidence of cementum, bone, or periodontal ligament (PDL) and, therefore, regeneration. In addition, there appeared to be some resorption of the dentin adjacent to the graft. Histological evaluation of the coronally advanced flap with EMD revealed new cementum, organizing PDL fibers and islands of condensing bone at a constant distance from the root surface.Conclusions: The subepithelial connective tissue graft in this study was found to have adhered to the root surface primarily by a connective tissue attachment with some evidence of root resorption. The coronally advanced flap with EMD was found histologically to have all the tissues necessary for regeneration: new cementum, organizing PDL fibers, and islands of condensing bone. These histologic sections strongly suggest that enamel matrix derivative works in a biomimetic fashion by mimicking the natural process of tooth development. J Periodontol 2003;74:1126‐1135.
Effects of Low‐Dose Cyclosporin on Osteogenesis of Human Demineralized Bone Grafts in a Surgically Created Mandibular Defect in Rats
Authors: Fu Earl , Tseng Yueh‐Chin , Shen E‐Chin , Hsieh Yao‐Dung , Chiang Cheng‐Yang 
Published: February 2005

Background: Demineralized freeze‐dried bone matrix (DFDBM) stimulates new bone formation; however, immune reactions from the residual antigens of prepared grafts might play a role in inducing osteogenesis. This study examined whether cyclosporine‐A (CsA), an immunosuppressant, enhanced the DFDBM‐induced new bone formation.Methods: After creating a bony defect in the posterior mandible, 40 male Sprague‐Dawley rats were divided into four groups of 10 each: no graft with mineral oil (control); no graft with CsA in mineral oil; DFDBM with mineral oil; and DFDBM with CsA in mineral oil (combined therapy). CsA was administered at 2 mg/kg body weight. Five rats in each group were sacrificed at days 10 and 28 and tissue samples were taken for histological examination.Results: Soft tissue was observed in the defects of all animals without grafts, whereas the repaired hard tissue formed in the defects of animals with grafts. Histometery, which was performed only at day 10, revealed both DFDBM and CsA therapies produced a significant increase in the total area of repaired hard tissue. Only CsA therapy significantly increased the new bone area. Compared with the DFDBM group, the composition of the repaired hard tissue in the combined therapy group shifted; i.e., the new bone area increased but the residual particle area decreased. The cartilage formation was greater in the combined therapy group than the DFDBM group.Conclusion: Within the limitations of this study, we suggest that the DFDBM grafts play a major role, which could be enhanced by CsA, in the induction of new bone formation, especially at an early phase. J Periodontol 2003;74:1136‐1142.
Modulation of Porphyromonas Gingivalis Proteinase Activity by Suboptimal Doses of Antimicrobial Agents
Authors: Grenier Daniel , Roy Elizabeth , Mayrand Denis 
Published: February 2005

Background: Antimicrobial agents are sometimes used as adjuncts for the treatment of aggressive and refractory forms of periodontitis. In this study, we used a culture plate assay to investigate the effect of suboptimal doses of antimicrobial agents on proteinase activity of Porphyromonas gingivalis.Methods: A culture plate assay using gelatin as the substrate, which allows a semiquantitative determination of proteinase activity, was developed. Suboptimal inhibitory concentrations of tetracycline, minocycline, doxycycline, metronidazole, penicillin G, or chlorhexidine were added to the medium, and proteolysis zones were determined following the growth of three strains of P. gingivalis. The effect of antimicrobials on outer membrane vesicleassociated gingipains also was determined.Results: The gelatin plate assay was a convenient, simple procedure for investigating the effect of suboptimal inhibitory concentrations of antimicrobial agents on proteinases produced by P. gingivalis. The largest reduction (>75%) in the proteolysis zones produced by three strains of P. gingivalis. was obtained with minocycline. Tetracycline and doxycycline also reduced the proteolysis zones. A suboptimal inhibitory concentration of chlorhexidine increased the proteolysis zones by up to 70%. Metronidazole and penicillin G produced no noticeable effect. The suboptimal inhibitory concentrations of minocycline, tetracycline, and doxycyline did not reduce the activity of outer membrane vesicleassociated Arg‐ and Lys‐gingipains.Conclusion: Results from this study suggest that sublethal concentrations of some antimicrobial agents in subgingival sites have the potential to affect the physiology of P. gingivalis., notably by increasing or decreasing the proteolytic activity of the bacteria. J Periodontol 2003;74:1316‐1319.
Adhesion and Growth of Cultured Human Gingival Fibroblasts on Periodontally Involved Root Surfaces Treated by Er:YAG Laser
Authors: Feist Iliria S. , De Micheli Giorgio , Carneiro Silvia R.S. , Eduardo Carlos P. , Miyagi Sueli P.H. , Marques Márcia M. 
Published: February 2005

Background: The application of Er:YAG laser irradiation, approved in 1997 to be used on dental hard tissues, has been investigated for periodontal therapy. The aim of this study was to analyze the biocompatibility of root surfaces treated by Er:YAG laser.Methods: Adhesion and growth of cultured human gingival fibroblasts on root surfaces treated by either irradiation with Er:YAG laser or curet were compared. Thirty single‐rooted teeth extracted because of periodontal disease were used. Calculus deposits on all experimental surfaces were removed, and the teeth were divided into three groups according to the applied treatment: group A, root planing with Gracey curet no. 3/4; group B, two irradiations with laser (60 mJ/pulse, 10 Hz; 10″ each with 10‐second interval, 3 J/cm2); group C, two irradiations with laser (100 mJ/pulse, 10 Hz; 10″ each with 10‐second interval, 5 J/cm2). Fragments (5 mm × 6 mm) were obtained from the experimental surfaces. Then, 1 × 103 cells were seeded on the top of each fragment. One, 2, and 3 days after seeding the specimens were prepared for scanning electron microscopy analysis, and the cells on the electronmicrographs were counted. The data obtained in triplicate were statistically compared by the Kruskall‐Wallis test complemented by the Dunn test (P ≤0.05).Results: Human gingival fibroblasts adhered to and grew on all treated surfaces. Group B presented a significantly higher cell count than did the other two groups at days 1 and 2. Three days after seeding the cultured fibroblasts of groups A and B reached total confluence. The cell count of group B was significantly higher than that of group C.Conclusion: The surfaces treated with 60 mJ/pulse Er:YAG laser irradiation promoted faster adhesion and growth than surfaces treated with either root planing or 100 mJ/pulse Er:YAG laser irradiation. J Periodontol 2003;74:1368‐1375.
The Application of Multilevel Modeling in the Analysis of Longitudinal Periodontal Data – Part I: Absolute Levels of Disease
Authors: Tu Yu‐Kang , Gilthorpe Mark S. , Griffiths Gareth S. , Maddick Ian H. , Eaton Kenneth A. , Johnson Newell W. 
Published: February 2005

Background: Statistical analyses of periodontal data that average site measurements to subject mean values are unable to explore the site‐specific nature of periodontal diseases. Multilevel modeling (MLM) overcomes this, taking hierarchical structure into account. MLM was used to investigate longitudinal relationships between the outcomes of lifetime cumulative attachment loss (LCAL) and probing depth (PD) in relation to potential risk factors for periodontal disease progression.Methods: One hundred males (mean age 17 years) received a comprehensive periodontal examination at baseline and at 12 and 30 months. The resulting data were analyzed in two stages. In stage one (reported here), the absolute levels of disease were analyzed in relation to potential risk factors; in stage two (reported in a second paper), changes in disease patterns over time were analyzed in relation to the same risk factors. Each approach yielded substantially different insights.Results: For absolute levels of disease, subject‐level risk factors (covariates) had limited prediction for LCAL/PD throughout the 30‐ month observation period. Tooth position demonstrated a near linear relationship for both outcomes, with disease increasing from anterior to posterior teeth. Sites with subgingival calculus and bleeding on probing demonstrated more LCAL and PD, and supragingival calculus had an apparently protective effect. Covariates had more “explanatory power” for the variation in PD than for the variation in LCAL, suggesting that LCAL and PD might be generally associated with a different profile of covariates.Conclusion: This study provides, for a relatively young cohort, considerable insights into the factors associated with early‐life periodontal disease and its progression at all levels of the natural hierarchy of sites within teeth within subjects. J Periodontol 2004;75:127‐136.
Study of Bacterial Viability within Human Supragingival Dental Calculus
Authors: Tan Benjamin T.K. , Mordan Nicola J. , Embleton Jason , Pratten Jonathan , Galgut Peter N. 
Published: February 2005

Background: There is evidence that supragingival calculus contains unmineralized channels and lacunae. The purpose of this study was to investigate the viability of bacteria within these areas.Methods: Supragingival calculus harvested from patients with moderate to severe chronic periodontitis was immediately frozen to –70°C. Six samples were cryosectioned, stained with a bacterial viability kit, and examined with fluorescence microscopy. Controls comprised heat treatment of cryosections prior to staining. Four additional samples were stained and examined whole a confocal laser scanning microscope (CLSM). Nine additional samples were prepared for bacterial culture, after initial irradiation with ultraviolet light to kill viable organisms on the covering plaque layer. Test samples were crushed to expose internal bacteria, while two controls were used without crushing.Results: Viable bacteria, as identified using the bacterial viability stain, were found within cavities/lacunae in supragingival calculus cryosections. Similar results were obtained from whole calculus samples using CLSM. Of the nine experimental samples where bacterial culture was attempted, five provided positive bacterial culture under both aerobic and anaerobic conditions; one showed positive growth under aerobic conditions only; while one showed no bacterial growth. The controls showed no bacterial growth.Conclusions: From this study, it appears that viable aerobic and anaerobic bacteria may be present within supragingival calculus, specifically within the internal channels and lacunae. Clinically, this may be important, since incomplete removal of supragingival calculus may expose these reservoirs of possible pathogenic bacteria and be a factor in the recurrence of periodontal diseases after treatment. J Periodontol 2004;75:23‐29.
Interleukin‐11 and IL‐17 and the Pathogenesis of Periodontal Disease
Authors: Johnson R.B. , Wood N. , Serio F.G. 
Published: February 2005

Background: Interleukin (IL)‐11 and IL‐17 are cytokines that modulate the inflammatory process and have not been assessed within normal or inflamed gingival tissues. Our purpose was to compare concentrations of human IL‐11 and IL‐17 within healthy and diseased human gingiva to determine their possible role in the initiation or progression of periodontal diseases.Methods: Biopsies from healthy (non‐hemorrhagic gingiva adjacent to a ≤3 mm gingival sulcus) and diseased gingiva (hemorrhagic gingiva adjacent to a ≥3 mm periodontal pocket) were studied. IL‐11, IL‐17, RANTES, and IL‐6 concentrations were assessed within solubilized gingival biopsies by enzyme‐linked immunosorbent assay. Data were compared by factorial analysis of variance and a post‐hoc Tukey honestly significant difference (HSD) test. Regression analysis and partial correlation analysis (adjusted for sample weight) were also used to determine correlations between the variables.Results: Interleukin‐11 concentrations were highest within gingiva adjacent to 3 mm diseased pockets (P <0.001), and IL‐17 concentrations were highest at 4 to 5 mm sites compared to other sites (P <0.001). Gingival concentrations of both cytokines were significantly lower in gingiva adjacent to a ≥6 mm pocket. RANTES concentrations were significantly greater in gingiva adjacent to ≥6 mm pockets than in tissues derived from other sites (P <0.001). IL‐11, IL‐6, and RANTES concentrations were significantly correlated with sulcular depth.Conclusions: Gingival concentrations of IL‐11 and IL‐17 are different in diseased gingiva adjacent to 3, 4 to 5, and ≥6 mm pockets, suggesting that their concentrations change as a consequence of the progression of gingivitis to periodontitis and that both cytokines could have a significant role in this progression. These data may be useful for the design of procedures for prevention of periodontal disease. J Periodontol 2004;75:37‐43.
Vascular Endothelial Growth Factor in Gingival Tissues and Crevicular Fluids of Diabetic and Healthy Periodontal Patients
Authors: Güneri Pelin , Ünlü Füsun , Yeşilbek Banu , Bayraktar Firat , Kokuludag Ali , Hekimgil Mine , Boyaciolu Hayal 
Published: February 2005

Background: Periodontal disease is one of the major oral problems encountered in patients with diabetes mellitus (DM). Vascular changes, neutrophil dysfunction, altered collagen synthesis, and genetic predisposition observed in DM may contribute to periodontitis; and the vascular alterations observed in such patients may depend on vascular endothelial growth factor VEGF) actions. Few reports are available about the mechanism of neovascularization and the angiogenic factors that contribute to the periodontal pathology and the role of VEGF in periodontal diseases. The aim of this study is to compare VEGF expression in healthy and periodontally diseased tissues with gingival crevice fluid (GCF) of healthy persons and diabetic patients.Methods: Gingival tissue and GCF samples were collected from sites of periodontitis in 10 healthy subjects and in 10 type 2 diabetic patients, and from the sites of healthy gingiva within the same groups. Therefore, each patient became his/her own control. Additionally, 10 people without any systemic or periodontal diseases were enrolled, forming a negative control group. Thus, a total of 50 tissue and 50 GCF samples were provided.Results: No VEGF staining was observed in the negative control group or in the systemically healthy people's healthy tissue samples, whereas four samples of diabetic patients showed positive staining (P <0.05). However, VEGF was revealed in two tissue samples of periodontal sites of systemically healthy people and in six samples of the diabetic patients (P >0.05). In all test groups, GCF VEGF levels were higher in periodontal sites (P <0.05) than in healthy sites.Conclusion: The results of this study showed that VEGF is increased in all periodontal tissues of both groups and in the healthy sites of diabetic patients. Additionally, GCF VEGF values increased in periodontal sites of all test groups. J Periodontol 2004;75:91‐97.
The Effect of Occlusal Discrepancies on Gingival Width
Authors: Harrel Stephen K. , Nunn Martha E. 
Published: February 2005

Background: A relationship between occlusal forces and gingival recession has been postulated in the past. However, minimal data are available to demonstrate a causal relationship between occlusal forces and recession.Methods: The records from a private practice limited to periodontics were reviewed to find patients who had complete periodontal examination records, including occlusal analysis and gingival width, that were recorded at least 1 year apart. Patients who fit this criteria were divided into those who had none of the recommended treatment (untreated, n = 30), those who had only non‐surgical treatment (partially treated, n = 20), and a control group who had completed all recommended surgical and non‐surgical treatment (completely treated, n = 41). The data for each tooth of each patient, including occlusal status and gingival width, were placed in a database and analyzed for a relationship between occlusal discrepancies and changes in gingival width.Results: No statistically significant relationship was detected between the presence of occlusal discrepancies and initial width of the gingival tissue (P = 0.414) or between occlusal treatment and changes in the width of the gingiva (P = 0.481).Conclusion: Based on the current study, there does not appear to be a relationship between occlusal discrepancies and gingival recession. J Periodontol 2004;75:98‐105.