bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Estrogen and Calcitonin Therapies on Bone Density in a Lateral Area Adjacent to Implants Placed in the Tibiae of Ovariectomized Rats
Authors: Duarte Poliana Mendes , César‐Neto João B. , Sallum Antonio Wilson , Sallum Enilson Antonio , Nociti Francisco H.
Published: February 2005

Background: This study evaluated the influence of estrogen and calcitonin administration on tibial bone density in a lateral area adjacent to implants placed in ovariectomized rats (OVX).

Methods: One screw‐type titanium implant was placed bilaterally in the ovariectomized rats, and the animals assigned to one of the following groups: group 1 (n = 15): sham surgeries; group 2 n = 15): OVX; group 3 (n = 14): OVX subcutaneously administered with calcitonin (CT) 4 days/week (16 IU/kg); group 4 (n = 14): OVX administered daily with 17β estradiol (20 µg/kg). After 60 days, the animals were sacrificed and undecalcified sections obtained. Blood samples were collected to measure serum levels of alkaline phosphatase and calcium at the time of sacrifice. Bone density was measured in a 500 µm wide mineralized zone lateral to the implant.

Results: Alkaline phosphatase levels in groups 2 and 3 P >0.05) were statistically higher than groups 1 and 4 (P <0.05), and calcium serum levels were higher in group 2 than the other groups (P <0.05). Regarding bone density, the data were grouped separately for cortical (zone A) and cancellous (zone B) bone. In zone A, intergroup analysis revealed no significant difference among groups (P >0.05). However, in zone B, the animals that received estrogen administration (group 4) presented a higher bone density than groups 2 and 3 (P <0.05).

Conclusion: It appears that estrogen therapy may prevent the negative influence of endogenous estrogen deficiency on bone density around titanium implants placed in ovariectomized rats. J Periodontol 2003;74:1618‐1624.
Prevalence of Human Herpesviruses in Patients with Aggressive Periodontitis
Authors: Yapar Mehmet , Saygun Işıl , Özdemir Atilla , Kubar Ayhan , Şahin Sermet
Published: February 2005

Background: Recent studies have demonstrated that various human viruses, especially cytomegalovirus (HCMV) and Epstein‐Barr virus type‐1 (EBV‐1), seem to play a part in the pathogenesis of human periodontitis. The aim of this investigation was evaluate the subgingival presence of HCMV and EBV in patients with aggressive periodontitis (AgP) and healthy subjects and to examine the effect of treatment on the incidence of these viruses months following surgery.

Methods: A polymerase chain reaction (PCR) method determined the presence of HCMV and EBV‐1. Subgingival plaque samples from 17 consecutive AgP patients and 16 healthy controls were collected. The following indices were measured: plaque index (PI), gingival index (GI), probing depths (PD), and clinical attachment loss (CAL). Clinical parameters were assessed pretherapy and at 3 months following surgical and antimicrobial therapy.

Results: HCMV was detected in 64.7% of AgP patients but not detected in healthy subjects (P <0.001) and EBV‐1 in 70.6% of AgP patients and 6.3% of the healthy controls (P <0.001). HCMV and EBV‐1 coinfection was detected in 41.7% of AgP patients. A statistically significant decrease was found in all clinical parameters 3 months after treatment. There was a statistically significant decrease in HCMV and EBV‐1 following therapy (P <0.001; no HCMV; 1 patient with EBV‐1).

Conclusions: These findings indicate that subgingival presence of EBV‐1 HCMV is strongly associated with aggressive periodontitis, and coinfection with HCMV and EBV‐1 appears to be particularly deleterious to periodontal health. J Periodontol 2003;74:1634‐1640.
Gingival Depigmentation by Erbium: YAG Laser: Clinical Observations and Patient Responses
Authors: Tal Haim , Oegiesser Dan , Tal Maya
Published: February 2005

Background: Melanin, carotene and hemoglobin are the most common natural pigments contributing to the normal color of the gums. Although physiologic and ethnic melanin pigmentation is not a medical problem, complaints about “black gums” are common. Gingival depigmentation has been carried out using non‐surgical and surgical procedures. Recently, laser ablation has been recognized as a most effective, pleasant and reliable technique.

Methods: The study included 10 patients who requested cosmetic therapy for melanin pigmented gums. Treatment was carried out using an erbium:YAG laser. The laser beam was set at 500 mJ/10 pulses/second. The beam was defocused to produce a 3 mm diameter circle, thus reducing the beam penetration to 2 to 4 µm/pulse while increasing the treated surface. The “brush” technique was applied until the gingival surface appeared clinically free of pigmentation. Patients were observed for 6 months. Each patient filled out a personal evaluation questionnaire for clinical analysis.

Results: Between 500 to 1,100 pulses/cm2 were recorded and a total of 800 to 2,200 pulses were required per patient, depending on the epithelium thickness and pigmentation. Treatment required only topical anesthesia. Healing was uneventful and required no supportive therapy. None of the patients experienced severe pain during or post‐operatively. Mild pain or itching was common during the first week. Treatment was reported as generally pleasant. Follow‐up during the 6 months showed no recurrences.

Conclusions: Depigmentation of gingival melanin pigmentation by erbium:YAG laser radiation in a defocused mode was a safe and effective procedure. The esthetic results were pleasing and healing was uneventful. Since the erbium:YAG laser is available in the dental office, it seems to be the laser of choice for this procedure.J Periodontol 2003;74:1660‐1667.
Augmentation of the Posterior Maxilla: A Proposed Hierarchy of Treatment Selection
Authors: Fugazzotto Paul A.
Published: February 2005

Literature is reviewed that discusses treatment results following Cauldwel Luc approach sinus augmentation therapy or osteotome sinus augmentation therapy, with and without simultaneous implant placement. A hierarchy of treatment selection for the augmentation of the posterior maxilla, based upon quantity and position of residual alveolar bone crestal to the floor of the sinus, is proposed. J Periodontol 2003;74:1682‐1691.
Vitamin D Receptor Alleles, Periodontal Disease Progression, and Tooth Loss in the VA Dental Longitudinal Study
Authors: Inagaki Koji , Krall Elizabeth A. , Fleet James C. , Garcia Raul I.
Published: February 2005

Background: The relationship between the vitamin D receptor (VDR) genotype and periodontal disease is not known. This study compared periodontal disease progression among polymorphisms of 2 VDR genes in men in the VA Dental Longitudinal Study.

Methods: Subjects were 125 medically healthy, middle‐aged men who had serial oral examinations over a mean 23‐year period. Probing depth, gingival bleeding on probing, clinical attachment loss (CAL), and alveolar bone loss (ABL) from radiographs were measured at each examination. Progression of periodontal disease was defined as the percentage of teeth per decade that increased ABL by ≥40%, and the percentage of teeth per decade that developed CAL ≥5 mm. ApaI and TaqI polymorphisms were determined from buffy coat cells following polymerase chain reaction (PCR) amplification. Mean changes in oral status were adjusted for baseline values of smoking status, number of teeth present, and periodontal status by analysis of covariance.

Results: Genotype distributions were 41 AA, 58 Aa, 26 aa; and 53 TT, 46 Tt, 26 tt. The AA genotype showed the highest rates of progression of ABL (5 ± 1% versus 1 ± 1% and 2 ± 1% teeth in Aa and aa, respectively; P = 0.03), CAL (37 ± 4% versus 17 ± 4% and 27 ± 6% teeth; P = 0.004), and tooth loss (2 ± 0.3 versus 1 ± 0.3 and 1 ± 0.4 teeth; P = 0.04). When genotype combinations were examined, progression of ABL, CAL, and tooth loss was highest in the AATT and AATt genotypes.

Conclusions: The ApaI polymorphism of the VDR gene is associated with oral bone loss, clinical attachment loss, and tooth loss in older men. Analysis of the VDR alleles may prove useful for predicting periodontal disease. J Periodontol 2003;74:161‐167.
Expression of Vascular Endothelial Growth Factor in Human Periodontal Tissues: Comparison of Healthy and Diabetic Patients
Authors: Ünlü Füsun , Güneri Pelin Gürdal , Hekimgil Mine , Yeşilbek Banu , Boyacioğlu Hayal
Published: February 2005

Background: Vascular endothelial growth factor (VEGF) induces proliferation of endothelial cells, stimulates angiogenesis, and increases vascular permeability, but information about its role in periodontal lesions is limited. The aim of this study is to determine the association between VEGF expression in healthy and periodontally diseased tissues of healthy and diabetic patients.

Methods: Ten systemically healthy and 10 Type 2 diabetic patients (DM) all diagnosed with periodontitis were enrolled into the study. Gingival samples were collected from both periodontal and healthy sites in all patients. Each patient served as his/her own control. Additionally, 10 people without any systemic or periodontal diseases were enrolled as a negative control group.

Results: In the negative control group tissue samples, no VEGF expression was observed. Among the 10 systemically healthy people, no evidence of VEGF was observed in healthy gingival samples, but was found in diseased tissues in 2 cases. In the diabetic patients, VEGF was observed in 4 healthy gingival tissues and in 6 periodontal sites. VEGF was intensely present in monocytes and macrophages.

Conclusion: The results of this study show that VEGF is increased in gingival tissues of diabetic patients, especially those with periodontal disease. J Periodontol 2003;74:181‐187.
Expression of Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of Metalloproteinases (TIMPs) in Healthy and Diseased Human Gingiva
Authors: Ejeil Anne‐Laure , Igondjo‐Tchen Sylvie , Ghomrasseni Sabah , Pellat Bernard , Godeau Gaston , Gogly Bruno
Published: February 2005

Background: The purpose of this study was to quantify the amount of matrix metalloproteinases such as MMP‐1, MMP‐2, MMP‐3, MMP‐7, MMP‐9, and MMP‐13 and tissue inhibitors of metalloproteinases TIMP‐1 and TIMP‐2 expressed by human gingival explants in culture media and the area fraction (AA%) of gingival collagen fibers according to the degree of inflammation, to investigate a possible correlation between these enzymes and collagen loss.

Methods: Gingival tissue specimens from 6 healthy controls (group 1), 17 patients with mild gingival inflammation (group 2), 10 patients with moderate gingival inflammation (group 3), and 9 patients with severe gingival inflammation (group 4) were placed in organ culture for 3 days. The MMPs and TIMPs in the culture media were quantified using zymography, dot blotting, and Western blotting. Paraffin gingival sections were stained with sirius red F3Ba for visualization of collagen fibers, then the area fraction (AA%) occupied by the gingival fibers was determined by automated image analysis.

Results: The AA% occupied by collagen fibers significantly decreased from group 1 (53%) to group 4 (35%). The decrease in collagen fibers was inversely correlated with the significant increase in MMP‐1, MMP‐9, and MMP‐13 (dot blotting analysis), with the increase of the active form of MMP‐2, and with the active form and proform of MMP‐9 (zymography analysis).

Conclusion: The present study showed that metalloproteinases, particularly MMP‐2, MMP‐9, MMP‐1, and MMP‐13, are involved in the gingival extracellular matrix degradation during periodontitis. J Periodontol 2003;74:188‐195.
Are Cytokines Linked to Collagen Breakdown During Periodontal Disease Progression?
Authors: Ejeil Anne‐Laure , Gaultier Frederick , Igondjo‐Tchen Sylvie , Senni Karim , Pellat Bernard , Godeau Gaston , Gogly Bruno
Published: February 2005

Background: Evidence of the role of cytokines produced by resident and inflammatory cells during inflammation is well established. The aim of this study was to quantify in healthy and diseased human gingiva the area fraction (AA%) occupied by collagen fibers and the amount of cytokines such as interleukin (IL)‐1β, IL‐4, IL‐6, tumor necrosis factor (TNF)‐α, transforming growth factor (TGF)‐β, and epidermal growth factor (EGF) to investigate a possible correlation between such cytokines, collagen degradation, and the gingival index.

Methods: Gingival tissue specimens from 6 healthy controls (group 1), 6 patients with mild gingival inflammation (group 2), 6 patients with moderate gingival inflammation (group 3), and 6 patients with severe gingival inflammation (group 4) were cultured for 72 hours, and the cytokines present in the culture media were quantified using an enzyme‐linked immunosorbent assay (ELISA). Paraffin gingival sections from the 24 subjects were stained with sirius red F3Ba for visualization of collagen fibers, then the area fraction (AA%) occupied by the gingival fibers was determined by automated image analysis.

Results: The present study revealed significant differences (P <0.05) between means of AA% in group 1 (53%), group 2 (41%), group 3 (39.5%), and group 4 (35%) for collagen fibers. Compared to controls, there were significant increases of IL‐1β (groups 3 and 4), IL‐6, and TNF‐α (group 3); a significant decrease of IL‐4 (groups 2, 3, and 4) and TGF‐β (groups 2 and 3); and no change of EGF. The collagen AA% was significantly correlated with the amounts of IL‐4 and TGF‐β, and significantly inversely correlated with the amounts of IL‐1β for all 3 inflamed groups and IL‐6 and TNF‐α for groups 2 and 3.

Conclusion: The present study showed that EGF was not changed in inflamed gingival tissue and that IL‐1β and IL‐4 were particularly and intensively correlated with collagen loss. These 2 cytokines could be markers of clinical severity during active periodontitis. J Periodontol 2003;74:196‐201.
Treatment of Advanced Periodontal Destruction With Immediately Loaded Implants and Simultaneous Bone Augmentation: A Case Report
Authors: Romanos George E.
Published: February 2005

Background: Advanced periodontal destruction is often associated with extraction of the teeth. Oral rehabilitation in these cases may include the traditional prosthetic restoration or an implant‐supported reconstruction. Immediately loaded implants present an alternative treatment modality using a bar in the anterior mandible, along with the placement of higher numbers of implants, which are connected with a fixed prosthetic reconstruction.

Methods: This clinical case report presents the surgical and prosthetic rehabilitation in a patient who had lost all teeth due to advanced periodontal bone destruction. Six implants were placed in the upper and lower jaw each. Some implants required guided bone regeneration in conjunction with autologous bone grafting. All of the implants were connected with their abutments, and a temporary fixed restoration was placed immediately after surgery. The final metalloceramic‐fixed reconstruction was cemented after 6 weeks of loading.

Results: All of the implants were osseointegrated and showed no clinical signs of mobility or infection. Mobility values were evaluated during healing and were found to be reduced. Radiological findings showed a stable peri‐implant bone level during the total 18‐month loading observation period.

Conclusions: This case report presents an alternative treatment concept for the oral rehabilitation in a patient with advanced periodontal destruction. The concept of immediate loading of implants might provide a better opportunity to meet patient needs than more traditional treatment modalities. J Periodontol 2003;74:255‐261.
The Effects of Progesterone on Matrix Metalloproteinases in Cultured Human Gingival Fibroblasts
Authors: Lapp Carol A. , Lohse Jennifer E. , Lewis Jill B. , Dickinson Douglas P. , Billman Michael , Hanes Philip J. , Lapp David F.
Published: February 2005

Background: Although pregnancy gingivitis is widely believed to result from elevated hormone concentrations, the mechanism(s) involved in the etiology of this condition remain unknown. Paradoxically, despite the apparent inflammation for a prolonged period, pregnancy gingivitis rarely progresses to periodontitis and usually resolves postpartum. We used several methods to test in vitro the hypothesis that the elevated progesterone levels of pregnancy might inhibit the production of some of the matrix metalloproteinases (MMPs) that are responsible for periodontal destruction

Methods: Cultured human gingival fibroblasts (GF) were tested in phenol red‐free, serum‐free medium with or without the progestogen, medroxyprogesterone acetate (MPA; 10–6 M), using interleukin‐1β (IL‐1β) to initiate immune responses and MMP production. These MMP responses were examined by macroarrays, reverse transcription‐polymerase chain reaction (RT‐PCR), zymograms, and enzyme‐linked immunosorbent assay (ELISA).

Results: Array analysis showed that pretreatment of GF with MPA reduced mRNA induction for MMPs‐1, ‐3, and ‐10 in response to 6 to 8 hours incubation with IL‐1β. RT‐PCR confirmed, that after 24 hours with IL‐1β, GF pretreated with MPA had undetectable levels of mRNA for MMPs‐1, ‐2, ‐3, ‐7, ‐10, and ‐13. Zymograms of culture media from this 24‐hour period showed reduction in several proteolytic activities. Examination of such 24‐hour media using ELISA for MMP‐3 and pro‐MMP‐13 confirmed that secretion of these enzymes was upregulated by IL‐1β and modulated downward by pretreatment with MPA.

Conclusions: Production by GF of numerous MMPs in response to IL‐1β was significantly reduced by progesterone. This steroidal modulation of proteolytic enzymes could help to explain why pregnancy gingivitis typically is not characterized by progression to periodontitis. J Periodontol 2003;74:277‐288.
Quantification and Localization of Platelet‐Derived Growth Factor in Gingiva of Periodontitis Patients
Authors: Pinheiro Maria Leticia B. , Feres‐Filho Eduardo J. , Graves Dana T. , Takiya Christina M. , Elsas Maria Ignez G. , Elsas Pedro Paulo , Luz Ricardo A.
Published: February 2005

Background: Platelet‐derived growth factor (PDGF) is a mitogen and chemoattractant for cells of mesenchymal origin. Overexpression of PDGF‐B can promote formation of inflammatory lesions in the lungs of transgenic mice. Moreover, continuous exposure to PDGF inhibits collagen production by osteoblastic cells. Thus, the expression of mitogenic factors in an inflammatory context may limit the differentiated function of cells, and thereby limit repair following periodontal attachment and bone loss. The goals of the present study were to test whether PDGF is present at increased levels in inflamed gingiva and to localize its expression in gingival biopsies from individuals with chronic periodontitis.

Methods: Tissues obtained during therapeutic procedures from inflamed and control sites of 9 patients were subjected to protein extraction, descriptive histology by hematoxylin and eosin, or immunohistochemistry assays. Quantification was calculated with an enzyme‐linked immunosorbent assay (ELISA) kit specific for PDGF‐AB. For the immunolocalization, anti‐PDGF‐A and ‐B antibodies were employed.

Results: PDGF concentration in the total protein extract was approximately 3 times higher in the inflamed sites (0.60 ± 0.18 ng/mg versus 0.20 ± 0.05 ng/mg; P = 0.03). Immunohistochemistry revealed prominent expression of PDGF in the pocket epithelial cells as well as the adjacent connective tissue. In contrast, little or no expression was detected in control biopsies devoid of the pocket epithelium and granulation tissue.

Conclusions: PDGF is present in increased levels in the human inflamed gingiva and is mainly localized to the pocket epithelium. It is possible that chronic expression of PDGF contributes to the inflammatory changes that occur during periodontal diseases. J Periodontol 2003;74:323‐328.
Treatment of Ligature‐Induced Peri‐Implantitis by Lethal Photosensitization and Guided Bone Regeneration: A Preliminary Histologic Study in Dogs
Authors: Shibli Jamil Awad , Martins Marilia Compagnoni , Nociti Francisco Humberto , Garcia Valdir Gouveia , Marcantonio Elcio
Published: February 2005

Background: The purpose of this pilot study was to evaluate the healing potential and reosseointegration in ligature‐induced peri‐implantitis defects adjacent to various dental implant surfaces following lethal photosensitization.

Methods: A total of 36 dental implants with 4 different surface coatings (9 commercially pure titanium surface [CPTi]; 9 titanium plasma‐sprayed [TPS]; 9 hydroxyapatite [HA]; and 9 acid‐etched [AE]) were inserted in 6 male mongrel dogs 3 months after extraction of mandibular premolars. After a 2‐month period of ligature‐induced peri‐implantitis and 12 months of natural peri‐implantitis progression, only 19 dental implants remained. The dogs underwent surgical debridement of the remaining dental implant sites and lethal photosensitization by combination of toluidine blue O (100 µg/ml) and irradiation with diode laser. All exposed dental implant surfaces and bone craters were meticulously cleaned by mechanical means, submitted to photodynamic therapy, and guided bone regeneration (GBR) using expanded polytetrafluoroethylene (ePTFE) membranes. Five months later, biopsies of the implant sites were dissected and prepared for ground sectioning and analysis.

Results: The percentage of bone fill was HA: 48.28 ± 15.00; TPS: 39.54 ± 12.34; AE: 26.88 ± 22.16; and CPTi: 26.70 ± 16.50. The percentage of reosseointegration was TPS: 25.25 ± 11.96; CPTi: 24.91 ± 17.78; AE: 17.30 ± 15.41; and HA: 15.83 ± 9.64.

Conclusion: These data suggest that lethal photosensitization may have potential in the treatment of peri‐implantitis. J Periodontol 2003;74:338‐345
Risk of Periodontitis in Systemic Lupus Erythematosus Is Associated with Fcγ Receptor Polymorphisms
Authors: Kobayashi Tetsuo , Ito Satoshi , Yamamoto Kouji , Hasegawa Hisashi , Sugita Noriko , Kuroda Takeshi , Kaneko Susumu , Narita Ichiei , Yasuda Keiko , Nakano Masaaki , Gejyo Fumitake , Yoshie Hiromasa
Published: February 2005

Background: Leukocyte Fc receptors for immunoglobulin G (FcγR) play a major role in the handling of immune complexes and pathogens in systemic lupus erythematosus (SLE) and periodontitis. Both diseases have been shown to be partly influenced by genetic components including FcγR genotype. The aim of this study was therefore to evaluate whether FcγR gene polymorphisms are associated with periodontitis risk in SLE patients.

Methods: The study subjects consisted of 42 SLE patients with periodontitis (SLE/P), 18 SLE patients without periodontitis (SLE/H), 42 healthy subjects with periodontitis (H/P), and 42 healthy subjects without periodontitis (H/H), who were all unrelated Japanese non‐smokers. Genomic DNA was isolated from peripheral blood, and FcγR genotypes for 3 biallelic polymorphisms (FcγRIIa‐R131/H131, FcγRIIIa‐158V/158F, FcγRIIIb‐NA1/NA2) were determined by allele‐specific polymerase chain reactions.

Results: The SLE/P group was found to have more mild levels of periodontal destruction than the H/P group (P < 0.01). There was a significant difference in the distribution of FcγRIIa genotypes between SLE/P and H/H groups (P = 0.004). A significant overrepresentation of the FcγRIIa‐R131 allele was found in the SLE/P group compared to the H/H group (SLE/P versus H/H: odds ratio [OR] 3.13, 95% confidence interval [CI] 1.46‐6.77, P = 0.0013). Furthermore, the prevalence of periodontitis was found to be 70% in SLE patients. The FcγRIIa‐R131 allele was also found to be overrepresented in the SLE/P group compared to the SLE/H group (SLE/P versus SLE/H: OR 3.40, 95% CI 1.18‐10.25, P = 0.011).

Conclusion:These results show the FcγRIIa‐R131 allele to be associated with periodontitis risk in SLE patients. J Periodontol 2003;74:378‐384.
Clinical and Histologic Aspects of Dental Implants Removed Due to Mobility
Authors: Piattelli Adriano , Scarano Antonio , Favero Lorenzo , Iezzi Giovanna , Petrone Giovanna , Favero Gian Antonio
Published: February 2005

Background: Implant failures are rare but do occur. Mechanical factors are certainly important in implant failures; so are biologic, iatrogenic, and functional factors. Mobility is the cardinal sign of implant failure. Three major etiologic factors have been suggested for implant failures: infection, impaired healing, and overload. The aim of the present study was to histologically and histochemically evaluate the fibrous connective tissue found around failed dental implants removed due to mobility.

Methods: In a 5‐year period, 51 root‐form implants were retrieved because of mobility and underwent histological examination. Thin ground sections were obtained from each implant.

Results: Almost all implants had been inserted in posterior (premolar‐molar) regions of both jaws. In all specimens, there was the presence of a 600 to 1,100 µm thick connective tissue between implants and surrounding bone. In every case, the surrounding bone was compact and highly mineralized, with well‐structured Haversian canals and few areas of remodeling. No bacteria were found in the most coronal portion of the implants. A scarce inflammatory cell infiltrate was present in the connective tissue of some specimens. In about 10% of specimens, the epithelium tended to surround the perimeter of the implant.

Conclusion: Our histological results are consistent with the hypothesis that late failures of osseointegrated implants can be caused by a combination of poor bone quality, mechanical trauma to bone, and overloading forces. J Periodontol 2003;74:385‐390.
Efficacy of Controlled‐Release Subgingival Chlorhexidine to Enhance Periodontal Regeneration
Authors: Reddy Michael S. , Jeffcoat Marjorie K. , Geurs Nico C. , Palcanis Kent G. , Weatherford Thomas W. , Traxler Barry M. , Finkelman Richard D.
Published: February 2005

Background: Periodontal regeneration success may be limited by placing bone grafts and membranes in infected sites. The objective of this study was to test the hypothesis that adjunctive subgingival administration of chlorhexidine gelatin bioresorbable chips enhances bone gain when used in conjunction with guided tissue regeneration.

Methods: This was a single center, blinded, 2‐arm parallel design study of 44 subjects with one or more sites with probing depth and clinical attachment loss ≥5 mm following initial therapy and radiographic evidence of bone loss. The patients were randomly assigned to receive either chlorhexidine (CHX) chip or sham chip placement one week prior to regenerative therapy that included graft placement and site coverage with guided tissue membranes. Patients also received CHX or sham chip placement, per their randomization, adjunctively to scaling and root planing or maintenance procedures. Periodontal examinations were completed at baseline (8 weeks prior to surgery); 1 week prior to surgery; and at 3, 6, and 9 months postsurgery. The major outcomes for the study were changes in bone height and bone mass as measured from standardized radiographs used for quantitative digital subtraction radiography over the 11‐month study period.

Results: Subjects receiving sham chip placement gained a mean bone height of 1.49 ± 0.22 mm, while patients receiving the CHX chips gained significantly more bone height (3.54 ± 0.45 mm; P <0.001). Similarly, subjects receiving CHX chips as an adjunct gained significantly more bone mass (5.57 ± 0.69 mg; P <0.001) than the standard therapy (2.59 ± 0.34 mg).

Conclusions: These pilot results indicate that locally delivered, controlled‐release antimicrobial treatment may improve the amount of bone gain during guided tissue regeneration procedures. These data support the evidence that infection control is an important variable in successful regeneration. J Periodontol 2003;74:411‐419.
The Effects of Cyclosporin on the Collagenolytic Activity of Gingival Fibroblasts
Authors: Hyland Paula L. , Traynor Patrick S. , Myrillas Theofilos T. , Marley John J. , Linden Gerard J. , Winter Paul , Leadbetter Nicola , Cawston Timothy E. , Irwin Chris R.
Published: February 2005

Background: The immunosuppressive agent cyclosporin is associated with a number of major side‐effects including the development of gingival overgrowth. Although the pathogenesis of cyclosporin‐induced gingival overgrowth remains unclear, it has been suggested that the finely regulated balance between extracellular matrix synthesis and degradation may be disturbed, resulting in an accumulation of excess connective tissue components within the gingival tissue. The aim of this study was to investigate the effect of cyclosporin on matrix metalloproteinases (MMP)‐1 and tissue inhibitors of MMP (TIMP)‐1 expression at the mRNA, protein, and enzyme activity levels.

Methods: Gingival fibroblasts were grown to confluence and then cultured in serum‐free medium supplemented with cyclosporin over the concentration range of 0 to 2000 ng/ml. MMP‐1 and TIMP‐1 mRNA levels in cultures were determined by reverse transcription polymerase chain reaction (RT‐PCR), protein levels in whole conditioned medium were assessed by enzyme‐linked immunosorbent assay (ELISA), and collagenolytic activity determined using a 3H‐acetylated type I collagen degradation assay. Tissue mRNA levels in normal and overgrown gingiva were also determined by RT‐PCR.

Results: Results indicated that cyclosporin inhibited MMP‐1 expression at both the mRNA and protein level in a dose‐ and time‐dependent fashion. The effects on TIMP‐1 expression were less clear, cyclosporin inhibiting mRNA expression, but having no effect on TIMP‐1 protein levels at any concentration studied. Addition of the drug resulted in reduced levels of collagenolytic activity in the culture medium. MMP‐1 mRNA expression was significantly reduced in overgrown compared to normal tissue.

Conclusions: These results add support to the hypothesis that the accumulation of collagen seen in gingival overgrowth can be explained by a cyclosporin‐induced inhibition of collagenolytic activity within the gingival tissues. J Periodontol 2003;74:437‐445.
In Vitro Evaluation of the Mitogenic Effect of Platelet‐Derived Growth Factor‐BB on Human Periodontal Ligament Cells Cultured with Various Bone Allografts
Authors: Papadopoulos C.E. , Dereka X.E. , Vavouraki E.N. , Vrotsos I.A.
Published: February 2005

Background: Several studies have documented the role of growth factors in periodontal regeneration. It has been shown that platelet‐derived growth factor (PDGF) is a potent stimulator of human periodontal ligament (PDL) cells. A variety of bone graft materials are used to treat osseous defects caused by periodontal disease. We evaluated the mitogenic effect of PDGF on human PDL cells cultured with different allografts to determine which of the allografts with or without PDGF promoted periodontal regeneration.

Methods: Two human demineralized freeze‐dried allografts of cortical (DFDBA) and cancellous (DFBA) bone and a non‐demineralized freeze‐dried allograft (FBA) from cancellous bone were used alone or supplemented with PDGF‐BB. Human PDL cultures were derived from the mid‐root of 2 maxillary premolars extracted for orthodontic reasons. Cells were grown separately in 24‐well dishes with or without 20 mg of each bone allograft. On day 2 of quiescence, new medium was added with 10 ng/ml of PDGFBB. DNA synthesis was estimated by measuring [3H] thymidine incorporation to determine the effects of the test agents on cell proliferation. Cells were processed and subjected to scintillation counting after 48 hours of incubation. Counts per minute (cpm/well) were determined for each sample.

Results: There was no statistically significant difference (P <0.05) on PDL cell proliferation when the allografts were used alone. PDL cells exhibited significantly greater proliferative responses to the 2 demineralized bone allografts, DFDBA and DFBA, when combined with PDGF‐BB. A statistically significant difference on DNA synthesis was noticed when PDGF‐BB was added to PDL cells cultured with FBA. PDL cells displayed no significant increase in mitogenic activity when cultured with PDGF‐BB alone.

Conclusions: The findings of this study demonstrate the beneficial role of DFDBA, DFBA, and FBA as synergic agents with PDGFBB to periodontal regeneration. The significant ability of the 2 decalcified bone allografts, DFDBA and DFBA, combined with PDGF to stimulate PDL cell proliferation might be a useful adjunct in the treatment of periodontal defects. J Periodontol 2003;74:451‐457.
Microvascular Response in the Periodontal Ligament Following Mucoperiosteal Flap Surgery
Authors: Nobuto Takahiro , Imai Hisao , Suwa Fumihiko , Kono Tomoo , Suga Hitoshi , Jyoshi Katuzi , Obayashi Kazuyoshi
Published: February 2005

Background: When the mucoperiosteal flap is elevated, the gingivo‐periosteal vascular plexus and periodontal ligament (PDL) vascular plexus sever their connection with the circulatory tracts that pass through alveolar bone. We studied the effect exerted on the PDL vascular plexus during restoration of the circulatory tract.

Methods: We performed experimental mucoperiosteal flap surgery in adult beagle dogs. Histological specimens, prepared after injecting India ink into the blood vessels on postoperative days 5, 7, 14, 21, 28, and 42, were examined under a light microscope. In addition, vascular corrosion cast specimens of the PDL, into which acrylic resin was injected, were observed using a scanning electron microscope.

Results: On postoperative day 5, the PDL vascular plexus had formed new blood vessels toward the bone side and root side, and bone resorption of the alveolar bone proper had initiated primarily around the opening of the Volkmann's canal. From postoperative day 7 to 14, the PDL vascular plexus formed new vessels on the bone side and root side accompanied by bone resorption of the alveolus, and demonstrated a complicated vascular architecture, which gradually organized and transformed into a mesh structure from postoperative day 21. Osteogenesis was initiated and encircled the newly formed vessels, and the alveolar bone proper recovered to a flat morphology. Judging from the quantity of new vessels and bone resorption, the width of the PDL space seemed to be the greatest on postoperative day 14.

Conclusions: When the mucoperiosteal flap was elevated, active wound healing was activated because of angiogenesis from the PDL, which possesses a microcirculatory system. Moreover, it was suggested that angiogenesis of the PDL vascular plexus and subsequent bone resorption of alveolar bone might temporarily reduce the tooth‐supporting function and cause postoperative mobility. J Periodontol 2003;74:521‐528.
Guided Bone Regeneration Around Titanium Plasma‐Sprayed, Acid‐Etched, and Hydroxyapatite‐Coated Implants in the Canine Model
Authors: Conner Kenneth A. , Sabatini Robert , Mealey Brian L. , Takacs Vincent J. , Mills Michael P. , Cochrann David L.
Published: February 2005

Background: Endosseous dental implants with rough surfaces have been designed to improve early healing, especially in areas of poor bone or insufficient bone quantity. The aim of this study was to histomor‐ phometrically assess the bone‐to‐implant contact on 3 different rough‐surfaced implants following guided bone regeneration.

Methods: Mandibulaf premolars and first molars were extracted in 12 dogs, and healing was allowed for 6 months. Six implant osteotomy sites were prepared, 3 per side, followed by the creation of 7.3 mm wide by 5 mm deep surgical defects in the coronal section of the osteotomy sites. Ten‐mm long titanium screw‐type implants with titanium plasma‐sprayed (TPS), hydroxyapatite‐coated (HA), or acid‐etched (AE) surfaces were placed; the surrounding defects were filled with canine demineralized freeze‐dried bone allograft: implants/grafts were covered with expanded polytetrafluoroethylene membranes; and the tissue was closed. Following a healing period of 4 months, the animals were sacrificed and mandibular blocks were harvested for histomorphometric analysis.

Results: The mean percentage of bone‐to‐implant contact in the defect and non‐defect areas for the different implant surfaces was: AE 16.24% defect, and 28.78% non‐defect; TPS 25.08% defect, and 16.96% non‐defect; and HA 48.25% defect and 26.60% non‐defect. Within the defect, the mean difference in the bone‐to‐implant contact was significant for HA compared to TPS (P<0.0001) and HA versus AE (P<0.0001); TPS versus AE was not significant (P = 0.063). In the non‐defect areas, the mean difference in the bone‐to‐implant contact was not significant for AE versus TPS (P = 0.010); all other comparisons were not significant. There were 18 membrane exposures in the 72 implant sites. Data were analyzed again to assess the impact of membrane complications. Using a 1‐way analysis of variance, the bone‐to‐implant contact was compared between the sites with and without membrane complications.

Conclusion: In this study, the bone‐to‐implant contact was greatest when an HA‐coated implant was used. J Periodontal 2003;74:658‐668
Minocycline‐Induced Staining of Torus Palatinus and Alveolar Bone
Authors: Ayangco Lilibeth , Sheridan Phillip J.
Published: February 2005

Background: Minocycline hydrochloride, an analog of tetracycline, is widely used in the treatment of acne. Its use has been associated with discoloration of teeth, bone, and other tissues.

Methods: A case is presented involving a patient with minocycline‐induced staining of the torus palatinus and alveolar bone.

Results: No treatment was rendered since the patient was not concerned with the appearance of the discoloration. The patient's dermatologist elected to change antibiotics.

Conclusions: Patients on long‐term minocycline therapy should be made aware of the possibility of pigmentation of bone and soft tissue that may be reversible with discontinuation of therapy; however, minocycline‐induced staining of the permanent dentition may not be reversible. J Periodontol 2003;74:669‐671.
Untreated Periodontal Disease: A Follow‐Up on 30 Cases
Authors: Harris Randall J.
Published: February 2005

Background: Many studies have shown that periodontal disease can be successfully treated. However, there is limited documentation as to what happens when periodontal disease is left untreated. This study examined patients in a private practice who were diagnosed with periodontal disease and did not complete any treatment. The goal was to see what happened to this group of untreated patients.

Methods: Thirty patients with periodontal disease were included in this study. After a mean period of 2.1 years without periodontal treatment, the patients were re‐examined and the changes which occurred evaluated.

Results: There was a statistically significant increase in probing depth (3.43 mm to 3.95 mm) and attachment loss (4.19 mm to 4.77 mm) and a statistically significant decrease in the number of teeth present (23.37 to 22.67). Twenty‐one teeth were lost, which was 3.0% of the teeth present at the time of initial diagnosis. The rate of tooth loss was 0.32 teeth/patient/year. The teeth that were lost had deeper recession, probing depths, and attachment loss than the teeth that were retained. Patient factors evaluated could not be associated with statistically significant changes in the clinical parameters, except that smokers had a greater number of sites gaining ≥2 mm of attachment and patients with the poorest oral hygiene had a greater percent of sites breaking down. However, certain site specific variables could be associated with statistically significant changes in the clinical parameters. These included sites: with bleeding on probing, associated with molar furcations, on interproximal surfaces, at posterior teeth, with probing depths ≥3.43 mm, with probing depths ≥7 mm, attachment loss ≥7 mm, and teeth with increased mobility.

Conclusions: This group of patients with untreated periodontal disease had greater breakdown and tooth loss than one would expect to see in a group of patients if their periodontal disease was treated. J Periodontol 2003;74:672‐678.
Treatment of Angular Bone Defects with a Composite Bone Grafting Material in Combination with a Collagen Membrane
Authors: Zitzmann Nicola U. , Rateitschak‐Plüss Edith , Marinello Carlo P.
Published: February 2005

Background: The purpose of this study was to evaluate the effect of a bioabsorbable collagen barrier (CB) in combination with a composite bone substitute (deproteinized bovine bone mineral with collagen, DBBM + C) in periodontal regeneration of angular bone defects in humans using a new application technique.

Methods: Twelve patients participated, each contributing at least 1 defect site, which exhibited a probing depth (PD) of ≥5 mm, a clinical attachment level (CAL) of ≥6 mm, and was positive for bleeding on probing (BOP) following initial therapy. Twenty‐two angular bone defects were filled with DBBM + C. A hole was placed in the membrane, which was then pulled over the tooth. The observation period was 2 years and included measurements of plaque, gingivitis, tooth mobility, PD, CAL, soft tissue recession, and bone level as assessed from standardized radiographs.

Results: The residual PD and CAL were reduced to 3.3 mm (PD) and 5.6 mm (CAL) with a CAL gain of 3.2 mm at 24 months. The radiographic defect reduction (bone fill) was 4.0 mm after surgery and 2.2 mm at 24 months. The changes measured clinically and radiographically were more pronounced in sites with a deep intrabony defect component than in sites with shallow ones.

Conclusions: These findings indicate that angular bone defects can be successfully treated with DBBM + C in combination with CB. A degradation of the filler material seems to occur particularly during the first 6 months, but without affecting the clinical parameters, which improved consistently. J Periodontol 2003;74:687‐694.
Root Coverage in Molar Recession: Report of 50 Consecutive Cases Treated with Subepithelial Connective Tissue Grafts
Authors: Harris Randall J.
Published: February 2005

Background: The purpose of this study was to evaluate root coverage of molar recession defects.

Methods: Fifty patients with a molar recession defect on one molar were treated with a subepithelial connective tissue graft. The procedure was performed as previously reported.

Results: Complete root coverage was obtained in 29 of the 50 defects (58%). A mean root coverage of 91.1% was obtained. There was a statistically significant decrease in recession depth (4.4 mm to 0.5 mm), increase in quantity of keratinized tissue (0.9 mm to 3.1 mm), decrease in probing depth (3.0 mm to 2.3 mm), and decrease in attachment level loss (7.4 mm to 2.8 mm).

Conclusion: The subepithelial connective tissue graft is an effective method to obtain root coverage of recession defects on molars. J Periodontol 2003;74:703‐708.
Novel Isolation of Alkaline Phosphatase‐Positive Subpopulation from Periodontal Ligament Fibroblasts
Authors: Murakami Yuya , Kojima Takehisa , Nagasawa Toshiyuki , Kobayashi Hiroaki , Ishikawa Isao
Published: February 2005

Background: Periodontal ligament fibroblasts (PDLFs) are the cells essential for periodontal regeneration. PDLFs comprise a heterogeneous cell population and consist of several cell subsets that differ in their function. It is known that PDLFs produce osteoblast‐related extracellular matrix proteins and show higher alkaline phosphatase (ALP) activity compared with gingival fibroblasts (GFs), implying that PDLFs have osteogenic characterisitics. The aim of the present study was to isolate the osteogenic population of PDLFs according to their expression of ALP.

Methods: PDLFs and gingival fibroblasts were separated into two populations, ALP‐positive and ALP‐negative, with an immunomagnetic method using a monoclonal antibody against human bone type ALP and magnetic beads conjugated with a secondary antibody. Expression of basic fibroblast growth factor (bFGF) receptor and transforming growth factor (TGF)‐β receptor was investigated in these two populations. Osteoblastrelated molecules, osteocalcin, and bone sialoprotein; ALP activity; and effect of bFGF on proliferation were also compared.

Results: Effective separation was confirmed in both PDLFs and GFs by flow cytometry. The expression of FGF receptor (FGFR) and TGF‐β receptor was significantly higher in ALPpositive PDLFs than in ALP‐negative PDLFs. ALP‐positive PDLFs also expressed higher mRNA levels of osteocalcin and bone sialoprotein compared with ALP‐negative PDLFs. The mitogenic effect of bFGF on ALP‐positive PDLFs was greater than that of ALP‐negative PDLFs.

Conclusions: These results indicate that osteoblastic and/or cementoblastic PDLF subsets could be isolated from the PDLF populations using an immunomagnetic method. Magnetic isolation of PDLFs may be a useful tool to obtain the cells which will potentially induce mineralization on the root surface. J Periodontol 2003;74:780‐786.
Effect of Er:YAG and Diode Laser Irradiation on the Root Surface: Morphological and Thermal Analysis
Authors: Theodoro Letícia H. , Haypek Patrícia , Bachmann Luciano , Garcia Valdir G. , Sampaio José E.C. , Zezell Denise M. , Eduardo Carlos de P.
Published: February 2005

Background: The aim of the present study was to compare the effects of Er:YAG and diode laser treatments of the root surface on intrapulpal temperature after scaling and root planing with hand instruments.

Methods: Fifteen extracted single‐rooted teeth were scaled and root planed with hand instruments. The teeth were divided into 3 groups of 5 each and irradiated on their buccal and lingual surfaces: group A: Er:YAG laser, 2.94 μm/100 mJ/10 Hz/ 30 seconds; group B: diode laser, 810 nm/1.0 W/0.05 ms/30 seconds; group C: diode laser, 810 nm/1.4 W/0.05 ms/30 seconds. The temperature was monitored by means of a type T thermocouple (copper‐constantan) positioned in the pulp chamber to assess pulpal temperature during and before irradiation. Afterwards, the specimens were longitudinally sectioned, and the buccal and lingual surfaces of each root were analyzed by scanning electron microscopy.

Results: In the Er:YAG laser group, the thermal analysis revealed an average temperature of −2.2 ± 1.5°C, while in the diode laser groups, temperatures were 1.6 ± 0.8°C at 1.0 W and 3.3 ± 1.0°C at 1.4 W. Electronic micrographs revealed that there were no significant morphological changes, such as charring, melting, or fusion, in any group, although the specimens were found to be more irregular in the Er:YAG laser group.

Conclusions: The application of Er:YAG and diode lasers at the utilized parameters did not induce high pulpal temperatures. Root surface irregularities were more pronounced after irradiation with an Er:YAG laser than with a diode laser. J Periodontol 2003;74:838‐843.