bluuebunny/crossref_metadata_2025 huggingface dataset:
Soluble CD14‐Dependent Intercellular Adhesion Molecule‐1 Induction by Porphyromonas gingivalis Lipopolysaccharide in Human Gingival Fibroblasts
Authors: Masaka Tamami , Hayashi Joichiro , Ishikawa Isao
Published: February 2005

Background: Intercellular adhesion molecule‐1 (ICAM‐1) is involved in the accumulation and activation of leukocytes in inflammatory sites through binding to β2 integrins expressed on leukocytes. We investigated whether or not lipopolysaccharide (LPS) derived from the periodontopathic bacterium Porphyromonas gingivalis affects ICAM‐1 expression on human gingival fibroblasts (HGF). CD14 is a receptor for LPS on monocytes and macrophages and is also present in serum as a soluble protein. We further examined the effects of serum and soluble CD14 (sCD14) on ICAM‐1 expression in HGF stimulated with P. gingivalis LPS.

Methods: HGF were prepared from explants of human gingival tissues and incubated in 96‐well culture plates before LPS stimulation. LPS derived from Escherichia coli O55:B5 and P. gingivalis ATCC 33277 LPS were employed. sCD14 was purified from normal human serum (NHS) by affinity chromatography using an anti‐CD14 monoclonal antibody. ICAM‐1 expression on HGF was measured by a cell enzyme‐linked immunosorbent assay.

Results: P. gingivalis LPS induced ICAM‐1 on HGF in a dose‐dependent manner in the presence of either 10% fetal calf serum or 2% NHS. The ability of P. gingivalis LPS to induce ICAM‐1 was comparable to that of LPS from E. coli at high LPS concentrations. In the absence of NHS, ICAM‐1 induction was negligible in HGF stimulated with P. gingivalis LPS, reaching a maximum at 2% NHS. The ICAM‐1 expression induced by P. gingivalis LPS was inhibited by a monoclonal antibody to CD14. Supplementation of serum‐free medium with sCD14 alone restored the capacity of HGF to respond to P. gingivalis LPS.

Conclusions: These results indicate that P. gingivalis LPS induces ICAM‐1 expression in HGF in an sCD14‐dependent manner. The overexpression of ICAM‐1 on fibroblasts in gingiva induced by P. gingivalis LPS seems to be involved in the retention of inflammatory cells in periodontitis lesions. J Periodontol 1999;70:772‐778.
Stress and Immunity: Implications for Viral Disease and Wound Healing
Authors: Rozlog Leigh A. , Kiecolt‐Glaser Janice K. , Marucha Phillip T. , Sheridan John F. , Glaser Ronald
Published: February 2005

It is now well established that psychological stress can downregulate the cellular immune response. Communication between the central nervous system and the immune system occurs via a complex network of bidirectional signals linking the nervous, endocrine, and immune systems. Stress disrupts the homeostasis of this network, which in turn, alters immune function. In this review, we discuss the role of stress in modulating cellular immune function and the potential health implications of this downregulation. J Periodontol 1999;70:786‐792.
Modification of an Osteoconductive Anorganic Bovine Bone Mineral Matrix With Growth Factors
Authors: Jiang Di , Dziak Rosemary , Lynch Samuel E. , Stephan Eugena B.
Published: February 2005

Background: Osteoconductive anorganic bovine bone mineral matrix material has been used clinically in bone regeneration procedures. Platelet‐derived growth factor‐BB (PDGF‐BB) and insulin‐like growth factor (IGF‐I) are important anabolic growth factors for bone. It was the aim of these studies to 1) examine the interaction of this bone graft material with PDGF‐BB and IGF‐I and 2) determine if the combination of growth factors with the matrix could stimulate osteoblastic cell proliferation.

Methods: Adsorption of PDGF‐BB and IGF‐I was done using 125I radiolabeled growth factors. The PDGF‐BB or IGF‐I was incubated with the anorganic bovine bone matrix, and the amount of adsorbed growth factor was measured. In the desorption studies, radiolabeled growth factors were adsorbed to the matrix material. The samples were incubated in buffer for various time periods, and the amount remaining on the matrix was measured to calculate the percentage of released growth factor. The biological activity was tested in an in vitro assay with primary culture neonatal rat osteoblastic cells. Porous bone matrix with known amounts of adsorbed PDGF‐BB or IGF‐I was produced. The osteoblastic cells were cultured on the bone mineral matrix, with and without adsorbed growth factor, and proliferation was assessed by 3H‐thymidine incorporation.

Results: Both PDGF‐BB and IGF‐I adsorbed to bone mineral matrix in a concentration‐dependent fashion. The affinity of IGF‐I for the material was IO‐fold greater than PDGF‐BB. In the experiments that measured the release of the initially adsorbed growth factors, approximately 50% of the PDGF‐BB and 10% of the IGF‐I were released after 10 days. PDGF‐BB adsorbed to the matrix material significantly (P <0.05, ANOVA) enhanced the proliferation of cultured osteoblastic cells compared to the mineralized matrix alone. However, IGF‐I adsorbed to the matrix material did not significantly enhance cell proliferation.

Conclusions: These results suggest that PDGF‐BB can be adsorbed to the anorganic bovine bone mineral matrix and that this growth factor subsequently enhances the osteogenic properties of this bone graft material. IGF‐I also adsorbed to the graft material; however, it was not readily released and it did not produce significant effects in the biologic assay. It appears that it may be clinically feasible to adsorb PDGF to anorganic bovine bone and that this combination of bone growth factor and mineral matrix has the potential for clinical applications. J Periodontol 1999;70:834‐839.
A Comparison of the Efficacy of 2 Powered Accumulation, Gingivitis, and Gingival Bleeding Toothbrushes in Affecting Plaque
Authors: Barnes Caren M. , Russell Carl M. , Weatherford III Thomas W.
Published: February 2005

Background: The purpose of this 30‐day blinded, parallel‐design study was to compare the effect of 2 powered toothbrushes, the Rowenta MH700 and the Braun Plak Control Ultra, on reducing plaque accumulation, gingivitis, and gingival bleeding in a cohort of 60 healthy adults.

Methods: After baseline evaluation of plaque, gingivitis, and gingival bleeding, subjects were randomly assigned to one of the experimental groups, provided written and verbal toothbrushing instructions, and had their teeth polished. At 2 weeks (follow‐up 1) and 4 weeks (follow‐up 2) all clinical parameters were again evaluated.

Results: The Braun group demonstrated a nearly significant reduction in gingival index (Gl) and a significant reduction in GI at follow‐up 2. The Rowenta group demonstrated significant reductions in GI, plaque index (PI), and bleeding index (GBI) at both follow‐up 1 and 2 examinations. At follow‐up 1, the Braun group demonstrated a nearly significant reduction in GI, a significant reduction in PI, and a non‐significant reduction in GBI. At follow‐up 2, the Braun group demonstrated a significant reduction in GBI, but not a significant reduction in PI. The reduction in GI for the Rowenta group was significantly greater (P values of 0.0001 and 0.0001, respectively) than that demonstrated in the Braun group. However, the Rowenta group did not demonstrate a significantly greater reduction in PI (P values of 0.7135 and 0.3184 for follow‐up 1 and follow‐up 2, respectively) or GBI than the Braun group at either examination (P values of 0.0663 and 0.3397 for followup 1 and 2, respectively).

Conclusions: The results of this study support the findings of numerous other studies that powered toothbrushes have great potential to remove plaque and improve gingival health and that the improvement can be demonstrated in a relatively short period of time. J Periodontol 1999;70:840‐847.
The Effect of Postsurgical Naproxen and a Bioabsorbable Membrane on Osseous Healing in Intrabony Defects
Authors: Bichara Jean , Greenwell Henry , Drisko Connie , Wittwer John W. , Vest Tracey M. , Yancey John , Goldsmith Jane , Rebitski George
Published: February 2005

Background: Previous reports in the literature have shown that non‐steroidal anti‐inflammatory drugs (NSAID) may affect osseous tissues by either stimulating or inhibiting bone formation. This effect can be drug specific and different NSAIDs may produce opposite results. There are also reports showing that NSAlDs inhibit bone loss due to inflammatory disease process. The purpose of this randomized, controlled, blinded, clinical investigation was to determine the effect of a one week course of postsurgical naproxen on the osseous healing in intrabony defects.

Methods: Twenty‐four vertical osseous defects in 24 patients were treated with either a bioabsorbable membrane plus twice daily postsurgical naproxen 500 mg for one week (test or GPN group) or with a polylactide bioabsorbable membrane alone (control or GA group). Twelve patients were included in each group. Treatment was performed on either 2‐ or 3‐wall or combination defects. All measurements were taken from a stent by a calibrated, blinded examiner and open measurements were repeated at the 9‐month second stage surgery. Power analysis to determine superiority of naproxen treatment showed that a 12 per group sample size would yield 87% power to detect a 2.0 mm difference and 64% power to detect a 1.5 mm difference.

Results: Open defect measurements from baseline to 9 months showed a statistically significant (P < 0.05) mean defect fill of 1.96 ± 1.27 mm and 2.04 ± 1.71 for the GPN and GA groups, respectively. This corresponded to a mean defect fill of 42% and a mean defect resolution of approximately 75% for both groups. The differences between GPN and GA groups were not statistically significant (P > 0.05). Defect fill of ≥ 50% was seen in 6 defects (50%) in the GPN group and in 5 defects (42%) in the GA group.

Conclusions: The administration of postsurgical naproxen failed to produce osseous healing that was statistically superior to that obtained with polylactide bioabsorbable membranes alone. J Periodonto1 1999;70:869‐877.
The Effect of Postsurgical Antibiotics and a Bioabsorbable Membrane on Regenerative Healing in Class II Furcation Defects
Authors: Vest Tracey M. , Greenwell Henry , Drisko Connie , Wittwer John W. , Bichara Jean , Yancey John , Goldsmith Jane , Rebitski George
Published: February 2005

Background: The purpose of this randomized, controlled, blinded, clinical investigation was to determine the effect of postsurgical antibiotics on osseous healing in Class II furcation defects.

Methods: Twenty‐four Class II furcation defects in 24 patients were treated with either a polylactide bioabsorbable membrane, demineralized freeze‐dried bone allograft (DFDBA) plus antibiotics (GBA or test group) or with a polylactide membrane and DFDBA alone (GB or control group). Twelve patients were included in each group. The antibiotic regimen consisted of ciprofloxacin 250 mg twice daily and metronidazole 250 mg tid for 1 week followed by a 7‐week regimen of doxycycline hyclate 50 mg daily. Treatment was performed on either mandibular buccal or lingual, or maxillary buccal Class II furcation defects. Defects were randomly selected by a coin toss for treatment and all open and closed measurements were performed by a blinded examiner. Final open and closed measures from a stent were repeated at the 9‐month second stage surgery. Power analysis to determine superiority of antibiotic treatment showed that a 12 per group sample size would yield 93% power to detect a 1.5 mm difference and 64% power to detect a 1 mm difference.

Results: Mean open horizontal probing depth reductions at 9 months were greater for the GBA group than for the GB group (2.92 ±1.78 versus 2.50 ±1.62 mm); however, these differences were not statistically significant. Seven of 12 furcations (58%) in the GBA group demonstrated >50% vertical defect fill at 9 months compared to 8 of 12 furcations (67%) in the GB group. There were no significant differences in mean open horizontal probing depth reduction between smokers and non‐smokers in either the GBA or GB groups. Membrane exposure did not appear to affect regenerative healing in either the GBA or GB groups.

Conclusions: The administration of postsurgical antibiotics did not produce statistically superior osseous healing of Class II furcation defects. This result may be attributable to membrane design which facilitates connective tissue ingrowth, thereby preventing bacterial downgrowth and contamination of the newly regenerated tissues. J Periodontol 1999;70:878‐887.
Resistance Profile Survey of 50 Periodontal Strains of Actinobacillus actinomycetemcomitans
Authors: Madinier Isabelle M. , Fosse Thierry B. , Hitzig Claude , Charbit Yves , Hannoun Lionel R.
Published: February 2005

Background: Antibiotic resistance has been increasingly described among bacterial species colonizing periodontal pockets, particularly in Prevotella and Porphyromonas spp. strains producing β‐lactamases, and frequently associated with resistance to tetracycline and erythromycin. These resistance genes may be carried on motile genetic elements, or transposons, capable of interspecies and intergeneric transmission among bacterial strains colonizing a same ecological niche. The aim of this prospective study was to determine the resistance profile of Actinobacillus actinomycetemcomitans and the prevalence of A. actinomycetemcomitans strains producing β‐lactamases in periodontal pockets.

Methods: Fifty strains of A. actinomycetemcomitans were isolated from 42 patients with adult periodontitis. No patient had periodontal or antibiotic therapy in the previous 6 months. Bacterial samples were collected from periodontal pockets ≥5 mm, appropriately diluted, inoculated onto selective medium (chocolate blood agar with bacitracin 75 μg/ml and vancomycin 5 μm/ml) and incubated for 5 days at 37°C in air with 5% CO2. After conventional identification, susceptibility testing to 11 antibiotics was performed by the broth dilution method, in trypticase soy broth supplemented with yeast extract, hemin, and 0.1% NaHCO3 to maintain microaerophilic conditions in the microtitration plate wells by CO2 formation.

Results: No strain demonstrated resistance to amoxicillin, amoxicillin‐clavulanic acid combination, pristinamycin, or ciprofloxacin at the breakpoint, but 40% of the strains were slightly resistant to penicillin G, and 4% were resistant to erythromycin, 90% to spiramycin, 18% to clarythromycin, 4% to tetracycline, 72% to metronidazole, and 12% to ornidazole. Amoxicillin, followed by tetracycline and erythromycin, was the most effective antibiotic on A. actinomycetemcomitans. The phenotypic research of a β‐lactamase was negative for all the strains tested.

Conclusions: In this work, most A. actinomycetemcomitans strains were resistant to metronidazole, but the amoxicillin‐metronidazole association may be of interest against subgingival anaerobic and capnophilic mixed flora. Pristinamycin and ciprofloxacin appeared as effective alternative monotherapies against A. actinomycetemcomitans. The threat of β‐lactam antibiotic resistance related to β‐lactamase production is currently not a problem with A. actinomycetemcomitans as it has been reported in oral anaerobes. J Periodontol 1999;70:888‐892.
Disposition of Alendronate Following Local Delivery in a Rat Jaw
Authors: Yaffe A. , Binderman I. , Breuer E. , Pinto T. , Golomb G.
Published: February 2005

Background: Recently, we have shown that local delivery of alendronate reduced significantly bone resorption activated by surgical separation of periosteum from bone. These results advocate the use of local application of alendronate in bone surgeries to prevent regional bone resorption at the surgery site. Here we investigated the efficacy absorbtion of alendronate by the bone from a gelatin sponge soaked with radiolabeled alendronate applied topically at the surgical site.

Methods: Following elevation of the mucoperiosteal flap next to premolars and molars of the rat mandible, a gelatin sponge soaked with 10 μl of radiolabled alendronate (1μCi/mg) was applied to exposed bone on one side. The local absorbtion of alendronate and its disposition in the contralateral side of the mandible as well as in the tibia bone were analyzed.

Results: The results show that 10% of total alendronate content of the gelatin sponge was absorbed in the bone locally (in the surgical site), while 0.2% was disposed in the tibia. Of interest is the fact that the surgical wound in the contralateral side increased the disposition of alendronate up to 2%. This finding is most likely the result of extravasation and diffusion of alendronate due to surgical wounding.

Conclusion: This study strongly supports our notion that local delivery of alendronate and its affinity to bone may become a very important treatment modality to prevent resorption of bone during dental and orthopedic procedures. J Periodontol 1999;70:893‐895.
Gastric and Gingival Localization of Mucosa‐Associated Lymphoid Tissue (MALT) Lymphoma. An Immunohistochemical, Virological and Clinical Case Report
Authors: Margiotta Valerio , Franco Vito , Rizzo Aroldo , Porter Stephen , Scully Crispian , Alberti Luca Di
Published: February 2005

Non‐Hodgkin's lymphomas (NHL) of the mucosaassociated lymphoid tissue (MALT) are characterized by their mucosal and glandular tissue localization. The case described here falls into the European‐American classification of a low‐grade B‐cell lymphoma of the MALT type, with a gingival lesion 2 years after a gastric lesion. The pathogenetic mechanisms of NHL in oral MALT and the diagnosis and treatment are discussed. J Periodontol 1999;70:914‐918.
Destructive Membranous Periodontal Disease (Ligneous Periodontitis)
Authors: Günhan Ömer , Günhan Meral , Berker Ezel , Gürgan Cem A. , Yildirim Hilal
Published: February 2005

Generalized membranous gingival enlargement due to accumulation of amyloid or fibrin‐like material is a rare, destructive and poorly defined disease entity. Some patients also show extraoral manifestations. The lesion is an involvement of periodontal tissues caused by the same process as ligneous conjunctivitis. In this report, 3 new cases, two of whom are siblings, are presented. Defective fibrinolysis and abnormal wound healing seem to be the main pathogenetic mechanism of this unusual disease, which should be evaluated systemically considering other mucosal involvement. J Periodontol 1999;70:919‐925.
Rotated Split Palatal Flap for Soft Tissue Primary Coverage Over Extraction Sites With Immediate Implant Placement. Description of the Surgical Procedure and Clinical Results
Authors: Nemcovsky Carlos E. , Artzi Zvi , Moses Ofer
Published: February 2005

Immediate implant placement after tooth extraction is becoming a common procedure in implant‐supported oral rehabilitation. However, lack of primary full flap closure can jeopardize final results. A surgical approach that would enable predictable primary soft tissue closure over implants placed into fresh extraction sockets is described and evaluated. This technique is based on a rotated deep split thickness palatal flap (RSPF) containing periosteum and connective tissue, covering the implant and/or a barrier membrane. In 29 patients, 33 consecutive implants were placed immediately post extraction of 1 or 2 anterior or premolar maxillary teeth. Patients were divided in 2 groups: Group A (15 patients; n = 18 sites) where no barrier membrane was used and Group B (14 patients, n = 15 sites) where an occlusive resorbable collagen membrane was used. Distance between the alveolar crestal bone and the coronal aspect of the implant was measured at time of implant placement (Group A: mean 1.9 mm, SD 1.16; Group B: mean 4.6 mm, SD 1.18) and at second stage surgery (Group A: mean 0.3 mm, SD 0.46; Group B: mean 0.7 mm, SD 0.7). The difference between both records (crestal bone formation) was calculated (Group A: 1.7 mm, SD 1.03; Group B: 3.9 mm, SD 1.12) and found to be statistically significant (P <0.0001). Crestal bone formation, relative to the initial bone crest‐implant distance at time of implant placement was approximately 85% in both groups. In 4 sites (2 in each group), where the cover screws were exposed before second stage surgery, complete crestal bone regeneration did not occur. Use of a barrier membrane may be obviated in appropriate cases while placing implants into fresh extraction sites. This procedure offers a predictable treatment approach in achieving complete soft tissue coverage, while allowing for healing of bony defects in immediate implantation procedures. J Periodontol 1999;70:926‐934.
Position Paper; Diabetes and Periodontal Diseases
Authors:   The Research, Science and Therapy Committee of The American Academy of Periodontology
Published: February 2005

This position paper on diabetes mellitus was prepared by the Research, Science and Therapy Committee of The American Academy of Periodontology. It is intended to: 1) update members of the dental profession on the diagnosis and medical management of patients with diabetes mellitus; 2) summarize current knowledge on the relation between diabetes mellitus and periodontal diseases; 3) provide an overview of factors in diabetic patients relevant to understanding the pathogenesis of periodontal diseases in these subjects; 4) outline special considerations associated with treatment of periodontal diseases in diabetic patients; and 5) discuss possible approaches to the management of diabetic emergencies in the dental office. J Periodontol 1999;70:935‐949.
Use of Bovine‐Derived Anorganic Bone Associated With Guided Tissue Regeneration in Intrabony Defects. Six‐Month Evaluation at Re‐Entry
Authors: Batista Eraldo L. , Novaes Arthur B. , Simonpietri C. Jeannette J. , Batista Felipe C.
Published: February 2005

Background: Different filling materials have been associated with guided tissue regeneration (GTR) in order to improve its regenerative potential and predictability. Anorganic bovine bone (ABB) has demonstrated biocompatibility and osteoconductive properties; however, there are limited data regarding its performance in the treatment of intrabony defects. This investigation aimed to evaluate the clinical outcome of the association of anorganic bovine bone with cellulose membranes in intrabony defects after 6 months.

Methods: Twenty‐six paired intrabony defects were selected from 11 non‐smoking patients with no relevant medical history. The defects were similar regarding the number of bony walls and defect depth, and presented pocket depths ≥ 6 mm. Four weeks after completion of basic therapy, probing depth (PD), clinical attachment level (CAL), and gingival margin position (GP) were recorded (baseline values). The defects were then surgically accessed and debrided, and the intrabony component measured to the nearest millimeter with periodontal probes and customized acrylic stents (distance from the stent to the base of the defect and from the stent to the alveolar crest). Each intrabony defect was randomly assigned to receive the membrane alone (control, C) or the membrane with anorganic bovine bone (test, T). The patients were re‐evaluated after 6 months, and re‐entry procedures were performed.

Results: Significant (P <0.01) improvement in all variables was observed: mean pocket reduction of 4.61 ± 1.60 mm (C) and 4.46 ± 1.50 mm (T) and clinical attachment gain of 2.85 ± 1.46 mm (C) and 3.15 ± 1.40 mm (T); the difference between groups was not significant (P >0.05). Nevertheless, gingival recession in the control group (1.84 ± 0.89 mm) was significantly (P <0.05) more pronounced than that observed in the test group (1.30 ± 0.48 mm). Bone measurements indicated a significant resolution of the defects (P <0.01). A mean defect resolution of 2.76 ± 0.72 mm (C) and 2.69 ± 1.03 mm (T) and crestal resorption of 1.07 ± 0.64 mm (C) and 1.30 ± 0.85 mm (T) were detected (P >0.05). Stepwise multiple regression analysis indicated that for both groups, the baseline depth of the defects and the alveolar crest resorption accounted for 82% of the variability of bone fill observed in the control group (F = 23.65, P <0.001) and 89% in the test group (F = 41.32, P <0.001).

Conclusions: ABB may be used in conjunction with GTR in the treatment of intrabony defects. Its use, however, did not result in a better outcome than the use of membranes alone. Studies employing more patients would be of interest in order to determine the advantages and indications of the tested approaches on a more predictable basis. J Periodontol 1999;70:1000‐1007.
Tetracycline‐Coated Polytetrafluoroethylene Barrier Membranes in the Treatment of Intraosseous Periodontal Lesions
Authors: Zarkesh Niloofar , Nowzari Hessam , Morrison John L. , Slots Jørgen
Published: February 2005

Background: Periodontal pathogens are detrimental to periodontal healing in barrier membrane‐assisted periodontal therapy. Tetracycline‐coating of barrier membranes may reduce levels of infecting pathogens. This study evaluated the clinical and microbiological effects of tetracycline‐coated expanded polytetrafluoroethylene (T‐ePTFE) barrier membranes in the treatment of 2‐ to 3‐wall intraosseous periodontal lesions around mandibular molars.

Methods: Eleven patients received non‐coated barrier membranes (ePTFE) and 11 patients received T‐ePTFE barrier membranes. Tetracycline coating was performed by placing ePTFE membranes first in a 5% tridodecylmethylammonium chloride solution and then in a basic 3% tetracycline solution. Microbiological examination included conventional culture and DNA probe analyses. Barrier membranes were removed 6 weeks after insertion.

Results: At baseline, the periodontal lesion depth averaged 8.0 mm in the ePTFE treated group and 7.4 mm in the T‐ePTFE group. At 1 year post‐treatment, the mean gain of probing attachment was 1.9 mm in the ePTFE group and 3.3 mm in the T‐ePTFE group (P = 0.02). At 3 minutes after membrane placement, suspected periodontal pathogens were detected in several ePTFE membranes but only in one T‐ePTFE membrane. At 6 weeks, all membranes showed periodontal pathogens, including Porphyromonas gingivalis, Fusobacterium species, Peptostreptococcus micros, Bacteroides forsythus, and motile rods.

Conclusions: This study suggests that the use of tetracycline‐coated ePTFE barrier membranes can result in additional gain of clinical periodontal attachment, most likely due to the antimicrobial properties of tetracycline during initial healing. J Periodontol 1999;70:1008‐1016.
Modulation of Androgen Metabolism by Estradiol‐17β and Progesterone, Alone and in Combination, in Human Gingival Fibroblasts in Culture
Authors: Tilakaratne A. , Soory M.
Published: February 2005

Background: Androgens, particularly 5α‐dihydrotestosterone (DHT), have anabolic effects on connective tissues and bone with implications on periodontal healing. This can be enhanced by estradiol‐17β (E‐17β), in synergy with androgen action. The effects of progesterone (P) contribute to plaque‐induced inflammatory changes. The aim of this investigation was to study the modulation of androgen metabolism by E‐17β and P, alone and in combination.

Methods: Human gingival fibroblasts were established in monolayer culture and duplicate incubations were performed in Eagle's MEM for 24 hours with either 14C‐testosterone (14C‐T) or 14C‐4‐androstenedione (14C‐4‐A) as substrate and serial concentrations of E‐17β, P and E‐17β + P. The medium was solvent extracted for steroid metabolites, analyzed, and quantified using a radioisotope scanner. The androgen substrates were converted mainly to DHT and 4‐androstenedione/testosterone from 14C‐T and 14C‐4‐A respectively.

Results: At concentrations of 0.1 and 0.5 μg/ml, E‐17β stimulated DHT synthesis from 14C‐T by 18% and 12%, respectively, decreasing to control values at 0.1 μg/ml. While the effect of similar concentrations of P on the same substrates was inhibitory by 18, 70, and 82% (n = 4; P <0.01). E‐17β + P showed a 12% increase in DHT synthesis over controls at 0.1 μg/ml, similar to that of E‐17β alone, despite the inhibitory effects of P (n = 4; P <0.01) with 12% and 77% decreases at 0.5 and 1 μg/ml (n = 4; P <0.01). The inhibitory effect of P on DHT synthesis was less apparent when E‐17β was present in combination. The formation of 4‐androstenedione from 14C‐T was stimulated by E‐17β (12.5%), inhibited by P (50%) and showed an intermediate response with E + P (33% stimulation). At the concentrations used, E‐17β stimulated DHT synthesis from 14C‐4‐A by 3.6‐, 3‐ and 2.6‐fold. P also stimulated this conversion from the same substrate by 16%, 2‐fold, and 1.6‐fold increases, partly due to the low yields at baseline. The combination of E + P stimulated the synthesis of DHT from 14C‐4‐A by 4‐fold at 0.1 and 0.5 μg/ml and a 2.3‐fold increase at 1 μg/ml. The formation of T from 14C‐4‐A was stimulated by E‐17β (50%) and inhibited by P (40%), with 93% stimulation by E + P at 0.1 μg/ml.

Conclusions: The modulatory effects of estradiol‐17β and progesterone on androgen metabolism may influence disease presentation and the progress of healing responses in the inflamed periodontium. J Periodontol 1999;70:1017‐1025.
Bone Regeneration by Recombinant Human Bone Morphogenetic Protein‐2 in Rat Mandibular Defects. An Experimental Model of Defect Filling
Authors: Higuchi Tatsuhiro , Kinoshita Atsuhiro , Takahashi Koichiro , Oda Shigeru , Ishikawa Isao
Published: February 2005

Background: Bone defects and irregularities are major problems for dental implant and periodontal therapies.

Methods: We investigated whether the application of recombinant human bone morphogenetic protein‐2 (rhBMP‐2) induces bone formation in through‐and‐through bone defects in the rat mandible. A round through‐and‐through bone defect (5 mm in diameter) was created in the angle of the mandible on both sides of the jaw using a steel round bur in each of 8 Long‐Evans rats. In the experimental group, polylactic acid‐polyglycolic acid copolymer/gelatin sponge PGS) containing rhBMP‐2 (6 μg/60 μl) was inserted in the bone defect. In the control group, the same carrier without rhBMP‐2 was applied in the bone defect on the opposite side. Four weeks after application, the rats were sacrificed. Step serial sections stained with hematoxylin and eosin at intervals of 200 µm were prepared in a bucco‐lingual direction. The size of the bone defects and new bone formation were evaluated histometrically.

Results: In all cases in the experimental group, a large quantity of newly formed bone was observed. The bone defects were completely filled with new bone in 4 of 8 rats in the experimental group. In the control group, small amounts of new bone formation were observed along the border of the original mandibular bone. Histometrical analysis revealed that the amount of new bone was significantly larger in the rhBMP‐2 treated sites than in the control sites (P <0.0001; paired t‐test).

Conclusions: These results indicate that the rhBMP‐2/PGS system induced effective bone regeneration on mandibular defects in rats. This procedure may be suitable as an experimental model for bone regeneration using various growth factors and effective for alveolar ridge augmentation followed by dental implant surgery. J Periodontol 1999;70:1026‐1031.
Association of a Vitamin D Receptor Gene Polymorphism With Localized Early‐Onset Periodontal Diseases
Authors: Hennig Branwen J.W. , Parkhill Judith M. , Chapple Lain L.C. , Heasman Peter A. , Taylor John J.
Published: February 2005

Background: Early‐onset periodontal diseases (EOP) are caused by interactions between host factors, specific microbial pathogens, and environmental factors. It is, therefore, of interest to investigate the nature of host factors as they may provide useful risk markers and reveal important information regarding the disease pathogenesis. Genetic polymorphisms in the vitamin D receptor (VDR) gene are associated with parameters of bone homeostasis and with diseases in which bone loss is a cardinal sign, in particular osteoporosis. Rapidly progressive bone loss is one feature of EOP. We, therefore, sought to determine whether EOP is associated with a polymorphism in the VDR gene.

Methods: A restriction fragment length polymorphism (RFLP) for Taq I in exon nine of the VDR gene was analyzed by PCR, followed by restriction digestion with Taq I and gel electrophoresis. We analyzed the genotypes of 69 EOP patients, including 20 patients with unequivocal evidence of localized disease (L‐EOP), and 72 controls with no history of EOP.

Results:The genotype distribution in the L‐EOP patient group was 7 (35%), 5 (25%) and 8 (40%) and in the control group 31 (43.1%), 36 (50.0%) and 5 (6.9%) for TT, Tt and tt respectively (where t and T represent the alleles with and without the Taq I RFLP respectively). χ2 analysis indicated that the distribution of the genotypes between these two groups was highly significantly different (P = 0.001). Allele frequencies were 47.5% and 52.5% for T and t in the L‐EOP group; 68.1% and 31.9% in the control group, showing a significant association between the prevalence of the less frequent allele (t) and L‐EOP (P = 0.017). There was no significant difference in the genotype distribution or the allele frequencies between the control samples and the larger EOP patient group (n = 69) which included patients with generalized and localized disease.

Conclusions: These data indicate that carriage of the less frequent allele of the Taq I RFLP (t) in the VDR gene significantly increases the risk of developing L‐EOP. However, VDR genotype may not affect the incidence of all cases of EOP. These findings contribute to our understanding of the genetic basis for periodontal disease and may help define sub‐groups of this disease which share common pathogenic factors. J Periodontol 1999;70:1032‐1038.
N‐Cadherin Expression During Periodontal Ligament Cell Differentiation In Vitro
Authors: Lin Wen‐Lang , Chien Hua‐Hong , Cho Moon‐Il
Published: February 2005

Background: When confluent periodontal ligament (PDL) cells were cultured in the presence of dexamethasone (Dex), ascorbic acid (AA), and β‐glycerophosphate (GP), they underwent sequential differentiation, demonstrating distinct morphological characteristics. At 1 week, localized cell proliferation led to the formation of multilayers of cells. As cell differentiation progressed, they formed nodules by deposition of matrix in the clusters of cells at 2 weeks, and mineralized the nodules at 3 weeks. These changes implicate extensive cell‐to‐cell interactions. Cadherins are known to play an important role in establishing cell contacts during tissue formation.

Methods: To determine whether cadherins are involved in PDL cell differentiation, and the formation and mineralization of nodules by the cells in vitro, we investigated the expression of N‐cadherin using immunofluorescence labeling and Northern blot analysis.

Results: Immunolabeling showed that N‐cadherin was expressed in PDL cells in the stages of nodule formation and mineralization. Northern blot analysis demonstrated a 3‐fold increase in the expression of N‐cadherin mRNA in the stages. However, neither E‐cadherin nor P‐cadherin was expressed.

Conclusions: Our data suggest that N‐cadherin may play an important role in PDL cell differentiation and the formation of mineralized nodules by PDL cells. J Periodontol 1999;70:1039‐1045.
Effect of a Carbon Dioxide Laser on Periodontally Involved Root Surfaces
Authors: Misra Vivek , Mehrotra K.K. , Dixit J. , Maitra S.C.
Published: February 2005

Background: The purpose of this in vitro study was to evaluate the effect of CO2 laser on the periodontally involved root surface, and to compare its efficacy with citric acid, EDTA and hydrogen peroxide in removal of root surface smear layer after root planing.

Methods: The study was conducted on 50 periodontally involved single rooted human teeth with poor prognosis. Immediately after extraction the teeth were scaled and root planed with Gracey curets; 50 specimens were obtained from the proximal side of each tooth which were assigned randomly to 1 of the 4 groups. Group A (35 specimens) was divided into 7 subgroups of 5 specimens each and irradiated with CO2 laser using a defocused mode at 3‐watt power for 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, or 1.4 seconds, respectively. Groups B, C, and D (5 specimens each) were treated with 6% hydrogen peroxide, EDTA solution (pH 7.4), or saturated citric acid solution (pH 1), respectively for 3 minutes. The specimens were then fixed and scanned using SEM.

Results: It was observed that surface smear layer was present on root surfaces of teeth that were root planed; the CO2 laser was not able to remove the smear layer on the sites that were irradiated for 0.2, 0.4 or 0.6 seconds at 3W power. Irradiation time of 0.8 seconds at 3W power was able to remove the smear layer, but the dentinal tubules were partially exposed. The surface irradiated for 1 second showed a flat appearance with many clear orifice of dentinal tubules. No change in diameter of exposed dentinal tubules was observed and their diameter was nearly equal that of normal dentinal tubules. Irradiation time of 1.2 and 1.4 seconds produced surface charring and carbonization and was totally ineffective in exposing the dentinal tubules; 6% hydrogen peroxide did not remove the smear layer completely and the exposed dentinal tubules orifice was not clear. EDTA (pH 7.4) and citric acid (pH 1) were found to be effective in removing the smear layer and exposing the dentinal tubules, which showed funnel shaped widening.

Conclusions: Surface smear layer was present on root surfaces of teeth that were root planed. Laser irradiation of 1 second at 3W completely removed the smear layer with minimal change in the diameter of the dentinal tubules. EDTA and citric acid were also effective in removing smear layer, but the exposed dentinal tubules showed funnel‐shaped widening. J Periodontol 1999;70:1046‐1052.
Should Cementoblasts Express Alkaline Phosphatase Activity? Preliminary Study of Rat Cementoblasts In Vitro
Authors: Gao Jin , Symons Anne L. , Haase Helen , Bartold P. Mark
Published: February 2005

Background: A well‐characterized cell culture model for cementoblasts is essential to understand the mechanisms of periodontal ligament (PDL) reattachment and regeneration. Whether cementoblasts express alkaline phosphatase (ALP) activity in vivo and in vitro remains to be determined.

Methods: Using a 2‐step method of enzyme digestion/explant culture, osteoblasts, gingival/PDL fibroblasts, and cementoblasts were obtained from alveolar bone, gingiva, and the root surface of rat first molars and cultured. Initially, bone sialoprotein (BSP) was immunolocalized on tissue sections of periodontium and on cultured cells to distinguish mineral‐forming cells from fibroblasts. Proteins were extracted from these cells to assess ALP activity by using an enzyme assay. RNA was extracted from the same cell source to detect ALP mRNA by reverse transcriptase polymerase chain reaction (RT‐PCR).

Results: Cultured PDL/gingival fibroblasts were spindle shaped. Osteoblasts were irregularly shaped, and cell clusters/nodules were observed as they approached confluence. The cementoblasts manifested a polygonal shape and had two morphotypes: osteoblast‐like and cuboidal or stratified. BSP was localized within the mineralized tissues and in osteoblasts and cementoblasts in culture and in tissue sections. The highest level of ALP activity was found in osteoblasts, a moderate level in PDL fibroblasts, and the lowest level in gingival fibroblasts. The cementoblasts lacked ALP activity, and this was reflected by a very weak signal (or no signal at all) for ALP mRNA in the cementoblasts.

Conclusions: These studies indicate that cells consistent with a cementoblast‐like phenotype may be successfully cultured, and that they lack ALP activity. J Periodontol 1999;70:951‐959.
Periodontal Tissue Disposition of Azithromycin in Patients Affected by Chronic Inflammatory Periodontal Diseases
Authors: Blandizzi Corrado , Malizia Tecla , Lupetti Antonella , Pesce Diego , Gabriele Mario , Giuca Maria R. , Campa Mario , Tacca Mario Del , Senesi Sonia
Published: February 2005

Background: The recognition that periodontal diseases are associated with specific pathogens has led to interest in the use of antibacterial drugs for inhibition of these microorganisms. On these bases, the present study was aimed at evaluating the tissue distribution of the new macrolide antibiotic azithromycin in patients subjected to oral surgery for chronic inflammatory diseases of both marginal and periapical periodontium.

Methods: Thirty‐two patients were treated with azithromycin 500 mg/day orally for 3 consecutive days, and drug concentrations in plasma, saliva, normal gingiva, and pathological periodontal tissues were evaluated. For this purpose, samples of blood, saliva, normal gingiva, granulation tissue, and radicular granuloma or cyst wall (from dentigerous cyst) were collected during oral surgery or 0.5, 2.5, 4.5, and 6.5 days after the end of pharmacological treatment; then, azithromycin levels were measured by a microbiological plate assay, using Micrococcus luteus NCTC 8440 as the indicator organism.

Results: The concentrations of azithromycin in plasma, saliva, normal gingiva, and pathological tissues reached the highest values 12 hours after the last dose (0.37 ± 0.05 mg/l, 2.12 ± 0.30 mg/l, 6.30 ± 0.68 mg/kg, and 11.60 ± 1.50 mg/kg, respectively) and then declined gradually. Consistent levels of the drug in normal gingiva and pathological tissues could be detected, however, up to 6.5 days, indicating that azithromycin was retained in target tissues for a long time after the end of treatment. Moreover, azithromycin levels in both normal gingiva and pathological tissues exceeded the minimum inhibitory concentrations of most pathogens involved in the pathophysiology of chronic inflammatory periodontal diseases. Notably, azithromycin levels in pathological tissues were significantly higher than those in normal gingiva 0.5, 2.5, and 4.5 days after the last dose.

Conclusions: The present results indicate a marked penetration of azithromycin into both normal and pathological periodontal tissues, suggesting that azithromycin represents a promising option in both adjunctive and prophylactic treatments of chronic inflammatory periodontal diseases. J Periodontol 1999;70:960‐966.
Enhanced Production of Mineralized Nodules and Collagenous Proteins In Vitro by Calcium Ascorbate Supplemented With Vitamin C Metabolites
Authors: Rowe Dorothy J. , Ko Susan , Tom Xenia M. , Silverstein Steven J. , Richards David W.
Published: February 2005

Background: Vitamin C or ascorbate is important in wound healing due to its essential role in collagen synthesis. To study wound healing in the periodontium, cells adherent to expanded polytetrafluoroethylene (ePTFE) augmentation membranes, recovered from edentulous ridge augmentation procedures, have been established in culture in our laboratories. The objective of this study was to determine whether treatment of these cells with a calcium ascorbate, which contains vitamin C metabolites (metabolite‐supplemented ascorbate), would increase the production of collagenous protein and mineralized tissue in vitro, as compared to unsupplemented calcium ascorbate (ascorbate).

Methods: Cells derived from ePTFE membranes were cultured with β‐glycerophosphate and the test agents for 2 to 5 weeks, and the surface areas of the cell cultures occupied by mineralized nodules were measured using computerized image analysis. One experiment tested the effects of calcium threonate, one of the vitamin C metabolites in metabolite‐supplemented ascorbate. Incorporation of radioactive praline and glycine was used as a measure of total protein (radioactivity precipitated by trichloracetic acid) and collagenase‐digestible protein (radioactivity released by collagenase digestion.) Co‐localization of collagen and fibronectin was examined by immunofluorescence.

Results: In vitro treatment of these cells with metabolite‐supplemented ascorbate increased the area of The cell cultures occupied by mineralized nodules after 5 weeks. Cell cultures treated with metabolite‐supplemented ascorbate also exhibited significant increases in total protein. The increase in collagenous proteins in these cultures accounted for 85% of the increase in total protein. The greatest difference between treatment groups was observed in the cell‐associated fraction containing the extracellular matrix. The additional collagen exhibited normal co‐distribution with fibronectin. In cultures treated with ascorbate spiked with calcium threonate, the area of mineralized tissue was significantly greater than in ascorbate‐treated cultures, but was less than the observed in cultures treated with metabolite‐supplemented ascorbate.

Conclusions: In vitro treatment with ascorbate containing vitamin C metabolites enhanced the formation of the mineralized nodules and collagenous proteins. Calcium threonate may be one of the metabolites influencing the mineralization process. Identifying factors which facilitates the formation of mineralized tissue has significant clinical ramifications in terms of wound healing and bone regeneration.J Periodontal 1999:70:992‐999
Chronic Ulcerative Stomatitis: A Case Report
Authors: Lorenzana Eduardo R. , Rees Terry D. , Glass Marcia , Detweiler Jeffrey G.
Published: February 2005

Background: Certain mucocutaneous diseases present with painful, ulcerative, or erosive oral manifestations. Chronic ulcerative stomatitis is a newly recognized disease of unknown origin which presents clinically with features of desquamative gingivitis. This report marks only the thirteenth case reported in the world literature. A review of previous reports and studies is presented along with a review of immunofluorescence techniques critical to proper diagnosis. These diseases are difficult to diagnose without the use of immunofluorescence techniques. A 54‐year‐old Caucasian woman presented with a 2‐ to 3‐year history of stomatitis and dry mouth.

Methods: Direct immunofluorescence revealed a speckled pattern of IgG deposits in the basal one‐third of the epithelium, while indirect immunofluorescence confirmed the presence of stratified epithelium‐specific antinuclear antigen (SES‐ANA), both pathognomonic for chronic ulcerative stomatitis.

Results: The patient was successfully treated using topical corticosteroid therapy. J Periodontol 2000;71:104‐111.
Enamel Matrix‐Derived Protein Stimulates Attachment of Periodontal Ligament Fibroblasts and Enhances Alkaline Phosphatase Activity and Transforming Growth Factor β1 Release of Periodontal Ligament and Gingival Fibroblasts
Authors: Van der Pauw Monique T. , Van den Bos Theo , Everts Vincent , Beertsen Wouter
Published: February 2005

Background: Although it is claimed that enamel matrixderived proteins (EMP) can be used to promote new attachment formation around periodontally involved teeth, the underlying biological mechanism is not understood. It was the aim of the present study to investigate the effects of EMP on the behavior of human periodontal ligament (HPLF) and gingival fibroblasts (HGF) in vitro, with special focus on their attachment properties, the expression of alkaline phosphatase (ALP) activity, the release of transforming growth factor (TGF)β1, and their proliferative rate.

Methods: Fibroblast populations were obtained from 10 individuals with a healthy periodontium and cultured in chemically defined medium on culture plates coated with EMP, purified collagen type I, or their respective vehicles. Experiments were performed in the absence of serum for periods up to 48 hours.

Results: It was shown that HGF barely attached and spread on EMP‐coated substrata, whereas HPLF attached and spread within 24 hours. However, when cultured on purified collagen type I, both cell types showed rapid attachment and spreading. Furthermore, the expression of ALP activity was significantly enhanced under the influence of EMP, especially in HPLF. HPLF and HGF both released significantly higher levels of TGFβ1 in the presence of EMP. EMP did not influence 3H‐thymidine incorporation by HPLF and HGF.

Conclusions: Our results indicate that HPLF and HGF respond differently to EMP. A more rapid attachment of HPLF to this substratum might contribute, during the initial stages of periodontal healing, to selective outgrowth and colonization of exposed root surfaces in vivo. J Periodontol 2000;71:31‐43.