bluuebunny/crossref_metadata_2025 huggingface dataset:
Estrogen and/or Calcium Plus Vitamin D Increase Mandibular Bone Mass
Authors: Hildebolt Charles F. , Pilgram Thomas K. , Dotson Mary , Armamento‐Villareal Reina , Hauser Jay , Cohen Sheldon , Civitelli Roberto
Published: February 2005

Background: We have previously reported that estrogen/ hormone replacement therapy (E/HRT) has beneficial effects on oral bone density over 3 years and that calcium and vitamin D supplementation has a lesser effect. Here we report on mandibular bone mass for 49 women (of the original cohort of 135) who continued in an additional 2‐year, open‐label extension.

Methods: Postmenopausal women were randomly assigned to receive calcium and vitamin D plus E/HRT, or calcium and vitamin D only. Regression analysis of mandibular bone mass over time was performed for each woman.

Results: Twenty‐two of 26 women who took calcium and vitamin D plus E/HRT for 5 years had small mandibular bone mass increases (0.35 ± 0.38%, P <0.001). Seventeen of 19 women who took only calcium and vitamin D for 3 years had increases in mandibular bone mass (0.74 ± 0.89%, P <0.002). The largest gains in mandibular bone mass occurred during the first 3 years of the study.

Conclusions: The data of this study indicate that E/HRT and/or calcium and vitamin D may result in increases of mandibular bone mass in postmenopausal women. Because of the longterm risks associated with E/HRT, caution should be exercised in prescribing E/HRT for prevention of chronic menopausal conditions. J Periodontol 2004;75:811‐816.
The Impact of Ethnicity, Gender, and Marital Status on Periodontal and Systemic Health of Older Subjects in the Trials to Enhance Elders' Teeth and Oral Health (TEETH)
Authors: Persson G. Rutger , Persson Rigmor E. , Hollender Lars G. , Kiyak H. Asuman
Published: February 2005

Background: Few studies have examined the association between periodontitis risk, gender, and marital status in older adults. The purpose of this study was to assess if the oral health status of older subjects could be explained by differences in: 1) marital status; 2) gender; and 3) ethnicity.

Methods: Clinical and radiographic periodontal oral conditions were studied in 701 older subjects from the TEETH clinical trial. Medical conditions as well as ethnic and marital status and smoking habits were considered.

Results: A total of 89 married couples were identified; 40.7% of these were of European descent and 48.1% of Chinese descent. The mean age was 67.7 years (SD ± 4.7). The men were older than the women (mean difference: 1.5 years, SD ± 4.6, 95% confidence interval [CI]: 0.5 to 2.5, P <0.01). No significant differences in periodontal conditions were found between spouses or by marital status. Chinese descent was associated with a higher risk for periodontitis, regardless of marital status (odds ratio: 1.5, 95% CI: 1.05 to 2.04, P <0.03).

Conclusions: 1) Married couples have similar social habits, similar oral health perceptions, and similar patterns of periodontal disease. 2) Dental studies including married couples do not bias data for married subjects as such. 3) Marital status has a limited impact on periodontal health but may have a greater impact on several systemic conditions, especially in widowed, divorced, or never married women. 4) Older Chinese subjects perceive themselves as being at lower risk for periodontitis but have more objective signs of periodontitis than older subjects of European descent. J Periodontol 2004;75:817‐823.
Morphometric Analysis of the Furcation Anatomy of Mandibular Molars
Authors: Santana Ronaldo B. , Uzel M. Ilhan , Gusman Heloisa , Gunaydin Yilmaz , Jones Judith A. , Leone Cataldo W.
Published: February 2005

Background: Successful treatment of molar furcation defects remains a challenge in clinical practice. Knowledge of anatomic factors facilitates predictable management of furcation involvement lesions. The degree of success in managing furcation involvement is inversely related to the horizontal probing depth. The depth of the horizontal component of attachment loss can vary depending on the external tooth‐surface reference points used. However, the anatomical factors affecting horizontal component of attachment loss have not been previously assessed. Therefore, this study determined the bucco‐lingual measurements of the cemento‐enamel junction and the mesial and distal roots and at the level of root separation.

Methods: One hundred extracted permanent human mandibular first (N = 50) and second (N = 50) molars were studied. Four horizontal bucco‐lingual widths were measured with calibrated calipers: 1) furcation entrance/roof (FE); 2) cemento‐enamel junction level (CEJ); 3) mesial root width (MRW); and 4) distal root width (DRW).

Results: The mean widths at FE, CEJ, MRW, and DRW were, respectively, 5.53 ± 0.45 mm, 8.71 ± 0.54 mm, 8.57 ± 0.54 mm, and 7.97 ± 0.65 mm in the first molars and 5.61 ± 0.65 mm, 8.40 ± 0.65 mm, 7.95 ± 0.88 mm, and 7.16 ± 0.84 mm in the second molars. Analysis of variance revealed significant differences between FE and the other variables tested. The results showed that the bucco‐lingual width of the furcation roof is considerably shorter than the MRW and DRW. The difference in the mean bucco‐lingual dimension between FE and the other measurements occurred in all teeth evaluated and varied between 0.7 and 4.30 mm.

Conclusions: Our findings demonstrate that clinical measurements of horizontal probing depth that use the external surfaces of roots as reference points overestimate the true anatomical component of furcation involvement in mandibular molars. Conversely, positive treatment outcomes in these teeth may be underestimated. This has implications not only for clinical practice but also for clinical research studies evaluating treatment outcomes. J Periodontol 2004;75:824‐829.
Meta‐Analysis of Local Metronidazole in the Treatment of Chronic Periodontitis
Authors: Pavia Maria , Nobile Carmelo G.A. , Bianco Aida , Angelillo Italo F.
Published: February 2005

Background: Meta‐analysis was used to assess the effectiveness of local delivery of metronidazole alone or as an adjunct to mechanical therapy in patients with chronic periodontitis.

Methods: Studies were identified using MEDLINE and other sources. Meta‐analyses were performed on the basis of probing depth (PD) at baseline and experimental and control regimens studied (i.e., metronidazole plus scaling and root planing [SRP] versus SRP and metronidazole versus SRP); the effect of local metronidazole on PD and attachment level (AL) was evaluated for follow‐up times of 4, 8, 12, 24, and 36 weeks. The DerSimonian & Laird random effects model was used.

Results: Twelve studies that met inclusion criteria were entered into the meta‐analysis. A significant mean reduction in PD for the combined metronidazole and SRP was observed in all comparisons with initial PD ≥4 mm (0.38 mm at 8 weeks to 0.6 mm at 12 weeks); whereas, with initial PD ≥5 mm a significant mean reduction was observed from 12 weeks (0.29 to 0.48 mm at 24 and 36 weeks, respectively). Meta‐analysis could be performed for AL to test the effectiveness of metronidazole as an adjunct to SRP and a significant AL improvement was found in all analyses (0.2 mm at 4 weeks to 0.29 mm at 24 and 36 weeks). Meta‐analyses were performed including two to four studies.

Conclusion: Our results demonstrated the effectiveness of metronidazole as an adjunct to SRP in the treatment of chronic adult periodontitis, but clinical significance and dissemination of antibiotics should be taken into account in the evaluation of metronidazole as an alternative to SRP. J Periodontol 2004;75:830‐838.
Effect of Periodontal Therapy in Smokers and Non‐Smokers With Advanced Periodontal Disease: Results After Maintenance Therapy for a Minimum of 5 Years
Authors: Papantonopoulos George H.
Published: February 2005

Background: Longitudinal clinical studies show smoking is a risk factor for periodontal disease progression. It has also been documented that smoking impairs healing after periodontal therapy. However, the longitudinal effect of smoking on treatment results in patients who undergo long‐term maintenance therapy has not been extensively investigated. This study clinically and radiographically compared smoking and non‐smoking patients who had been treated for advanced periodontal disease and who received maintenance therapy for a minimum of 5 years.

Methods: Twenty‐nine patients were selected over a 6‐month period when they presented for a regularly scheduled visit in a private office. Patients were selected on the basis of initially having lost 50% of bone support on 50% of their teeth; had received follow‐up therapy for at least 5 years; were compliant at 75% of the appointments; and had plaque scores <20% in 75% of the visits. All patients had received non‐surgical and surgical therapy as required for pocket elimination. Fourteen were active smokers during the entire maintenance period. Clinical measurements of probing depths and presence of plaque and gingivitis and a new set of standardized radiographs were taken.

Results: Smokers had higher mean radiographic bone loss values prior to treatment (7.52 ±1.39 versus 6.65 ±1.39) and at the final examination (7.32 ±1.42 versus 6.29 ±1.29) mean radiographic bone loss as well as initial, immediate post‐therapy, and final percent of pockets ≥6 mm (1.42% ±1.87% versus 0.60% ±1.11%). Differences were not statistically significant. Over 5 to 8 years, seven sites in four non‐smokers and 11 sites in six smokers exhibited radiographic bone loss ≥2 mm. One tooth in a non‐smoker and three teeth in two smokers were lost. In a logistic regression analysis, smoking increased the odds ratio 10.7 times of having ≥1 site with bone loss ≥2 mm.

Conclusion: The present study on a small group of patients treated for advanced periodontal disease and well maintained over 5 to 8 years showed no statistically significant differences between smokers and non‐smokers in clinical probing depth and radiographic bone loss measurements. J Periodontol 2004;75:839‐843.
The Effects of an Amine Fluoride/Stannous Fluoride and an Antimicrobial Host Protein Mouthrinse on Supragingival Plaque Regrowth
Authors: Pizzo Giuseppe , Guiglia Rosario , La Cara Monica , Giuliana Giovanna , D'Angelo Matteo
Published: February 2005

Background: Chlorhexidine (CHX)‐containing mouthrinses are recommended as adjuncts to mechanical oral hygiene. The problem associated with side effects, however, has stimulated the search for alternative antiplaque agents. The aim of this study was to investigate the plaque inhibitory effects of two mouthrinses containing amine fluoride/stannous fluoride (ASF) and antimicrobial host proteins (lactoperoxidase, lysozyme and lactoferrin; LLL), respectively.

Methods: The study was an observer‐masked, randomized 4×4 Latin square cross‐over design balanced for carryover effects, involving 12 healthy volunteers in a 4‐day plaque regrowth model. A 0.12% CHX mouthrinse and a saline solution served as positive and negative controls, respectively. On day 1, subjects received professional prophylaxis, suspended oral hygiene measures, and commenced rinsing with their allocated rinses. On day 5, subjects were scored for disclosed plaque.

Results: The ASF rinse showed a significant inhibition of plaque regrowth in comparison to both saline and LLL solutions, but the lowest plaque indices were obtained with the CHX formulation (P < 0.01). There were no significant differences between LLL rinse and saline (P > 0.05). Such pattern of efficacy was the same in anterior and posterior teeth and in vestibular and lingual surfaces as well, with the exception of the lingual anterior surfaces. In these sites, differences between the CHX and ASF rinses were not significant (P > 0.05). A significantly higher prevalence of side effects was found in subjects using the CHX product (P < 0.0042).

Conclusions: Although the effect on plaque regrowth observed with 0.12% CHX rinsing was superior to that with ASF, the ASF rinse was not associated with side effects. These findings, together with those from long‐term trials, suggest that the ASF rinse may represent an effective alternative to CHX rinse as an adjunct to oral hygiene. On the contrary, the LLL rinse did not significantly inhibit plaque regrowth.
Effect of Enamel Matrix Derivative on Periodontal Ligament Cells In Vitro Is Diminished by Porphyromonas gingivalis
Authors: Inaba Hiroaki , Kawai Shinji , Nakayama Koji , Okahashi Nobuo , Amano Atsuo
Published: February 2005

Background: Enamel matrix derivative (EMD) has been shown to possess a mitogenic effect to induce effective periodontal regeneration, however, it is unclear whether periodontal pathogens can modulate the effect of EMD. The present study examined the influence of Porphyromonas gingivalis on EMD‐stimulated periodontal ligament (PDL) cells.

Methods:P. gingivalis ATCC33277 and its mutants deficient in fimbriae (ΔfimA) or gingipains (ΔrgpA ΔrgpB, Δkgp, and ΔrgpAΔrgpB Δkgp) were employed. PDL cells were grown on EMDcoated dishes and infected with P. gingivalis wild strain or a mutant. Cell migration and proliferation were then evaluated with an in vitro wound healing assay. The expression of transforming growth factor‐ β1 (TGF‐β1) and insulin‐like growth factor I (IGF‐I) mRNA by PDL cells was examined. Further, the degradation and phosphorylation of extracellular signal‐regulated kinase 1 and 2 (ERK1/2) as well as paxillin in infected PDL cells were estimated using Western blot analysis.

Results:P. gingivalis ATCC33277 inhibited the migration and proliferation of PDL cells on EMD‐coated dishes, and the mutants ΔfimA, ΔrgpAΔrgpB, and Δkgp showed the same effects. Further, each of these organisms diminished the expression of TGF‐β1 and IGF‐I mRNA, as well as the phosphorylation of ERK1/2 from EMD‐stimulated PDL cells. In addition, total paxillin protein was markedly degraded by both the wild‐type strain and each of the mutants except for ΔrgpAΔrgpBΔkgp, which showed a negligible effect in all of the assays with EMD‐stimulated PDL cells.

Conclusion: These results suggest that P. gingivalis diminishes the effect of EMD on PDL cells in vitro through a cooperative action of gingipains. J Periodontol 2004;75:858‐865.
Tongue‐Cleaning Methods: A Comparative Clinical Trial Employing a Toothbrush and a Tongue Scraper
Authors: Pedrazzi Vinícius , Sato Sandra , de Mattos Maria da Glória Chiarello , Lara Elza Helena Guimarães , Panzeri Heitor
Published: February 2005

Background: It is estimated that approximately 85% of all halitosis cases have their origin within the mouth; of these, 50% are caused by tongue residues. Previous studies have established that hydrogen sulfide and mercaptans are the primary components of halitosis. Thus, tongue cleaning gains importance as a means of halitosis management.

Methods: This investigation compared the efficacy of two mechanical methods for tongue cleaning through a handheld sulfide monitor. This crossover trial was carried out with 10 healthy subjects, 20 to 50 years old. Before the baseline measurement of the volatile sulfur compounds (VSCs), the subjects were instructed to refrain from any tongue cleaning method for 48 hours. The 10 participants were then placed in one of two groups (five each): 1) first week: tongue scraper, second week: soft‐bristle toothbrush; 2) first week: toothbrush, second week: tongue scraper, with a 48‐hour wash‐out period between each week.

Results: The baseline measurements were compared with those of the end of each week using the Dunn method (α = 0.01). The tongue scraper showed a 75% reduction in VSCs, while the toothbrush only achieved a 45% reduction in VSCs.

Conclusion: Although the tongue coating was removed by both methods, the tongue scraper performed better in reducing the production of volatile sulfur compounds. J Periodontol 2004;75:1009‐1012.
Biomimetic Approach on Human Periodontal Ligament Cells Using Synthetic Oligopeptides
Authors: Kim Tae‐II , Jang Jun‐Hyeog , Lee Yong‐Moo , Rhyu In‐Chul , Chung Chong‐Pyoung , Han Soo‐Boo , Choi Sang‐Mook , Ku Young
Published: February 2005

Background: Periodontal ligament (PDL) cells, connecting root cementum with alveolar bone, are important for periodontal wound healing. In order to obtain a predictable periodontal regeneration, selective adhesion and proliferation of PDL cells are essential. The purpose of this study was to investigate the effects of synthetic peptides mimicking cell‐binding domain of fibronectin (FN) on human PDL cells.

Methods: Two types of oligopeptides, Gly3‐Pro‐His‐Ser‐Arg‐ Asn‐Gly6‐Arg‐Gly‐Asp‐Gly (G3PHSRNG6RGDG) and Gly3‐His‐ Pro‐Asn‐Arg‐Ser‐Gly6‐Arg‐Gly‐Asp‐Gly (G3HPNRSG6RGDG), were constructed using a solid‐phase peptide synthesizer. Fibronectin type III ninth to tenth domain (FN III 9‐10) and Arg‐Gly‐Asp‐Ser (RGDS) were prepared for comparison with the effects of synthetic peptides. These peptides were coated onto 96‐well cell culture plates with 0.001 ∼ 100 μM concentrations. Cultured human PDL cells were then applied to the peptide‐coated wells at a density of 1 × 104/well. After 1 hour incubation at 37°C, adhered cells were fixed, stained, and examined by phase contrast microscopy for cell spreading assay. Attached PDL cells were solubilized with 2% sodium dodecyl sulfate (SDS) for the cell attachment assay by measuring absorbance at 595 nm in microplate reader. Western blot analysis was performed to determine extracellular signal‐regulated kinase (ERK1/2) activity.

Results: Cell attachment and spreading assays revealed that G3PHSRNG6RGDG (≥10 μM) possesses similar adhesive behavior to FN III 9‐10. G3PHSRNG6RGDG showed a comparable ERK1/2 activity when compared to FN III 9‐10.

Conclusions: G3PHSRNG6RGDG enhanced an attachment and spreading of human PDL cells thereby increasing ERK1/2 activity. Taken together, it is anticipated that this peptide might be a potential tool for arranging a biologically attractive environment for PDL cells, which would enhance periodontal regeneration efficacy. J Periodontol 2004;75:925‐932.
Substance P Enhances the Inhibition of Osteoblastic Cell Differentiation Induced by Lipopolysaccharide From Porphyromonas gingivalis
Authors: Azuma Hideki , Kido Jun‐ichi , Ikedo Dai , Kataoka Masatoshi , Nagata Toshihiko
Published: February 2005

Background: Substance P (SP) is a multifunctional neuropeptide that transmits pain signals, regulates the immune system, and may modulate emotional stress. SP stimulates bone resorption activity of osteoclasts, and SP level in gingival crevicular fluid is correlated with the degree of periodontal inflammation. However, the exact roles of SP in bone metabolism and periodontal diseases are poorly understood. To elucidate the effect of stress on bone metabolism, we investigated the effect of SP on osteoblastic cell differentiation in the presence of lipopolysaccharide from Porphyromonas gingivalis (P‐LPS).

Methods: The primary osteoblastic cells were isolated from fetal rat calvaria (RC) and cultured with SP, P‐LPS, and an SP antagonist (SPa). The effects of SP on bone nodule (BN), alkaline phosphatase (ALPase) activity, mRNA expressions of SP receptor, bone matrix proteins, and Cbfa 1 were investigated.

Results: SP stimulated the expression of SP receptor mRNA in RC cells and enhanced its expression in the presence of P‐LPS (50 ng/ml). SP inhibited BN formation and ALPase activity in a dose‐dependent manner (10−7 to 10−5 M) and further suppressed mRNA expression of bone sialoprotein, osteopontin, and osteocalcin but not of type I collagen mRNA. The inhibitory effects were enhanced in the presence of P‐LPS and blocked by Spantide III. Furthermore, the expression of Cbfa 1 mRNA was also markedly suppressed in the presence of SP and P‐LPS.

Conclusion: These findings suggest that SP inhibits osteoblastic cell differentiation and may be related to bone metabolism in periodontal diseases under conditions of stress. J Periodontol 2004; 75:974‐981.
Effect of Tranilast on Matrix Metalloproteinase‐1 Secretion From Human Gingival Fibroblasts In Vitro
Authors: Maita Eikichi , Sato Mami , Yamaki Keiko
Published: February 2005

Background: Some drugs such as phenytoin, calcium blockers, or cyclosporins are known to cause gingival fibrous hyperplasia, an unwanted side effect. Decreased collagen catabolism in overgrown gingival tissue has been proposed as one of the reasons causing the disease. The effect of tranilast, which suppresses collagen synthesis and cell proliferation, on matrix metalloproteinase (MMP‐1) secretion from human gingival fibroblast, was studied in vitro.

Methods: Human gingival fibroblasts were cultured from specimens taken from healthy, periodontal, and overgrown gingival tissues. The effects of tranilast on cell proliferation and MMP‐1 secretion from gingival fibroblast were assessed. Inhibitory effect of transforming growth factor (TGF)‐β secretion from gingival fibroblast by tranilast was also evaluated.

Results: Tranilast did not interfere with cell proliferation at the low concentrations. MMP‐1 concentration significantly increased at the lower doses of tranilast up to about 2‐fold compared to controls (P <0.05). In contrast, higher doses of tranilast signi‐ ficantly decreased activity to 30% and 20%, respectively. MMP‐1 secretion was inhibited significantly by phenytoin, nifedipine, and cyclosporin A and the depressed MMP‐1 recovered to the control level with tranilast. The amount of secretion from normal and periodontitis gingival fibroblast specimens did not differ, but that from the overgrown gingiva was significantly less than the other types. Moreover, TGF‐β secretion was significantly inhibited by 300 µM of tranilast.

Conclusions: Tranilast upregulates the expression of type 1 collagenase suppressed by gingival overgrowth‐inducing drugs, and inhibits TGF‐β secretion from gingival fibroblasts. Therefore, tranilast could be considered as an agent for controlling gingival overgrowth. J Periodontol 2004;75:1054‐1060.
Subantimicrobial Dose Doxycycline Enhances the Efficacy of Scaling and Root Planing in Chronic Periodontitis: A Multicenter Trial
Authors: Preshaw Philip M. , Hefti Arthur F. , Novak M. John , Michalowicz Bryan S. , Pihlstrom Bruce L. , Schoor Robert , Trummel Clarence L. , Dean John , Van Dyke Thomas E. , Walker Clay B. , Bradshaw Mark H.
Published: February 2005

Background: Previous studies have shown that subantimicrobial dose doxycycline (SDD) is of clinical benefit in the treatment of chronic periodontitis (CP). The aim of this study was to further assess the role of SDD as an adjunct to scaling and root planing (SRP) in the treatment of CP.

Methods: A double‐blind, randomized, placebo‐controlled, multicenter clinical study was conducted to test the efficacy of SDD (20 mg doxycycline B.I.D.) in combination with SRP in subjects with moderate to severe CP. Two‐hundred ten subjects were treated with a standardized episode of SRP and randomized to receive either adjunctive SDD or placebo for 9 months. Efficacy parameters included per‐subject mean changes in clinical attachment level (CAL) and probing depth (PD) from baseline, and the total number of sites with attachment gains and probing depth reductions ≥2 mm and ≥3 mm from baseline.

Results: In periodontal sites with PD 4 to 6 mm and ≥7 mm (N = 209, intent‐to‐treat population), mean improvements in CAL and PD were greater following SRP with adjunctive SDD than SRP with placebo, achieving statistical significance in all baseline disease categories at month 9 (P <0.05). At month 9, 42.3% of sites in the SDD group demonstrated CAL gain ≥2 mm compared to 32.0% of sites in the placebo group (P <0.01). CAL gain ≥3 mm was seen in 15.4% of sites in the SDD group compared to 10.6% of sites in the placebo group (P <0.05). When considering the same thresholds of change in PD, 42.9% of sites in the SDD group compared to 31.1% of sites in the placebo group demonstrated PD reduction ≥2 mm (P <0.01), and 15.4% of sites in the SDD group compared to 9.1% of sites in the placebo group demonstrated PD reduction ≥3 mm (P <0.01).

Conclusion: Adjunctive subantimicrobial dose doxycycline enhances scaling and root planing. It results in statistically significant attachment gains and probing depth reductions over and above those achieved by scaling and root planing with placebo. J Periodontol 2004;75:1068‐1076.
Possible Periodontal Pathogens Associated With Clinical Symptoms of Periodontal Disease in Japanese High School Students
Authors: Suda Reiko , Kobayashi Makoto , Nanba Rieko , Iwamaru Megumi , Hayashi Yoshinori , Lai Chern‐Hsiung , Hasegawa Kohji
Published: February 2005

Background: The purpose of this study is to investigate how the components of biofilm and clinical oral status change in adolescents and to identify specific periodontal pathogens as risk markers for the onset of periodontitis.

Methods: One hundred seven high school students (72 boys and 35 girls, all 15 years old) were recruited. The mesio‐lingual site of the left lower first molar was selected as the examined site. Probing depth (PD), bleeding on probing (BOP), the presence of subgingival calculus, and Community Periodontal Index (CPI) were determined by examination with a WHO probe. The prevalence and proportion of seven selected periodontal pathogens (Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia, Campylobacter rectus, Eikenella corrodens, and Actinobacillus actinomycetemcomitans serotypes b and c) were determined by indirect immunofluorescent technique, and the prevalence and proportion of spirochetes were determined by their morphology under dark‐field microscopy. The relationship between the periodontal status and the bacterial condition was statistically analyzed.

Results: The mean proportion of T. forsythensis was significantly higher in BOP (+) sites compared with BOP (−) sites (3.47% ± 5.35% versus 0.83% ± 1.95%) and in CPI 3 sites compared with CPI 0 sites (3.29% ± 5.28% versus 0.68% ± 1.37%). The mean proportion of C. rectus was significantly increased in BOP (+) compared with BOP (−) (2.01% ± 2.48% versus 0.79% ± 0.91%) and in CPI 3 sites compared with CPI 0 sites (2.04% ± 2.64% versus 0.80% ± 0.79%).

Conclusion: The results indicated that T. forsythensis and C. rectus might be able to be used as risk markers for the onset of periodontitis. J Periodontol 2004;75:1084‐1089.
Tetracycline Impregnation Delays Collagen Membrane Degradation In Vivo
Authors: Zohar Ron , Nemcovsky Carlos E. , Kebudi Edmon , Artzi Zvi , Tal Haim , Moses Ofer
Published: February 2005

Background: Guided tissue and bone regeneration using bioabsorbable collagen membranes is a common practice. Collagen promotes progenitor cell adhesion, chemotaxis, homeostasis, and physiologic degradation with low immunogenicity, which makes it an ideal material for barrier preparation. Collagen membranes have to maintain integrity for a proper time, thus ensuring successful cell exclusion. Early collagen membrane degradation is detrimental for the success of regenerative procedures. This in vivo study was conducted to evaluate the effect of soaking collagen membranes in different tetracycline hydrochloride (TCN) concentration solutions on its degradation.

Methods: Five mm disks of collagen membrane were soaked in either 100 mg/ml TCN (group 100) or 50 mg/ml TCN (group 50); a group of non‐treated disks served as controls. All disks were labeled with aminohexanoyl‐biotin‐N‐hydroxy‐succinimide ester (biotin) and implanted in rat calvaria bone. Block sections were taken after 3 weeks and histological slides stained with horseradish peroxidase (HRP) to detect remnants of biotinylated collagen. Staining intensity was analyzed by image‐analysis software taking quadruplicate measurements of a 500 µm2 area each. Data were analyzed using analysis of variance (ANOVA) with repeated measures and paired t test with Bonferroni correction.

Results: Staining intensity of membranes in group 100 was >5‐fold higher than the control while group 50 exhibited >11‐fold higher intensity than the control and >2.5‐fold higher than the 100. All of these differences were statistically significant (P <0.001).

Conclusion: Soaking collagen membranes in 50 mg/ml TCN solution is a useful, practical, and simple tool to slow membrane degradation. J Periodontol 2004;75:1096‐1101.
The Interface Between Retained Roots and Dental Implants: A Histologic Study in Baboons
Authors: Gray Jonathan L. , Vernino Arthur R.
Published: February 2005

Background: This study is a derivative of another study evaluating implant efficacy in baboons. In the previous study it was noted that some implants were placed near or into retained root tips. The purpose of this study was to evaluate the effect of the inadvertent placement of root form implants into or near retained root fragments.

Methods: The baboon has severe dilacerations at the apices of the roots, making extraction very difficult; 120 teeth were extracted from 10 baboons. After the sites had healed, root form implants were placed in each of the sites. Sites were either loaded at various time intervals or left unloaded. Block sections were removed and processed for histologic examination.

Results: When the specimens were analyzed, it was noted that several implants were placed through retained root fragments, while others were placed through the periodontal ligament of other root fragments. In a few cases, implants were close to, but not in contact with, either the root or the periodontal ligament. These implants functioned as well as the others in the study. Histologically, there was no inflammation at any site. In some sections, the roots were in intimate contact with the implants, while in others, there was a gap between the two. Where the implant was in contact with the periodontal ligament, there was no apparent fibrous encapsulization of the implant. In some areas, it appeared that a calcified material was deposited on the implants. It was not possible to determine whether this material was bone or cementum.

Conclusion: Unintentional placement of dental implants into retained root fragments did not result in any inflammation and may have produced cementum or cementum‐like matrix on the titanium surface adjacent to the periodontal ligament of the retained root tip. J Periodontol 2004;75:1102‐1106.
Localization of the NO‐cGMP Signaling Pathway Molecules, NOS III‐Phosphorylation Sites, ERK1/2, and Akt/PKB in Osteoclasts
Authors: Korkmaz Yüksel , Baumann Michael A. , Schröder Hannsjörg , Behrends Sönke , Addicks Klaus , Raab Wolfgang H. M. , Bloch Wilhelm
Published: February 2005

Background: Nitric oxide (NO) mediates different cellular functions by activating soluble guanylate cyclase (sGC) that converts guanosine‐5'‐ triphosphate (GTP) to cyclic guanosine‐3', 5'‐monophosphate (cGMP). Membrane‐bound GCs produce cGMP in response to natriuretic peptides in osteoblasts, but neither the NO‐target enzyme sGC, nor the phosphorylation sites of NOS III, nor their regulation by extracellular signalregulated kinases 1 and 2 (ERK1/2) and Akt/protein kinase B (Akt/PKB) in osteoclasts have been established.

Methods: Rat molars with periodontium were perfusion‐ and postfixed, decalcified, and frozen‐sectioned. Free‐floating sections were stained using nicotinamide adenine dinucleotide phosphate‐diaphorase (NADPH‐d) and tartrate‐resistant acid phosphatase (TRAP) histochemical techniques and immunoreacted with antisera against NOsynthase (NOS) I‐III, NOS III phoshorylated at Thr495, NOS III phoshorylated at Serine1177 (Ser1177), ERK1/2, phosphorylated ERK1/2, Akt/PKB, phosphorylated Akt/PKB, sGC (α2/β1), and cGMP.

Results: NADPH‐d staining and immunostaining of NOS I‐III, NOS III phosphorylated at Ser1177, ERK1/2, Akt/PKB, phosphorylated Akt/PKB, sGC (α2 and β1‐subunits), and cGMP were detected in osteoclasts. Immunohistochemical reaction products for NOS III phosphorylated at threonine495 (Thr495) and phosphorylated ERK1/2 could not be identified in osteoclasts. Comparison of TRAP activity and immunostaining for sGC β1‐subunit revealed that sGC β1‐subunit is only expressed in a subpopulation of osteoclasts.

Conclusions: NO is likely to be generated by NOS I and NOS III in osteoclasts. The inconstant expression of NOS II in some osteoclasts may be explained with inducible expression of NOS II upon physiological cell activation. Localization of the sGC α2‐ and β1‐subunits and cGMP in osteoclasts is compatible with an involvement of NO‐sGC signaling in the homeostasis of osteoclasts. The phosphorylation site of NOS III at Ser1177 and phosphorylated Akt/PKB are involved in regulation of NO production by NOS III in osteoclasts under basal conditions. J Periodontol 2004;75:1119‐1125.
Comparison Between Subtraction Radiography and Conventional Radiographic Interpretation During Long‐Term Evaluation of Periodontal Therapy in Class II Furcation Defects
Authors: Cury Patricia R. , Araujo Ney S. , Bowie Jon , Sallum Enilson A. , Jeffcoat Marjorie K.
Published: February 2005

Background: Limited information comparing digital subtraction radiographic assessment with conventional radiographic interpretation is available from longitudinal clinical trials. The aim of this study was to evaluate the ability to detect periodontal bone changes during the long‐term maintenance of Class II furcation defects by conventional radiographic interpretation compared to interpretation of digital subtraction images.

Methods: Standardized radiographs of 18 Class II furcation defects in mandibular molars were taken at baseline and at 6, 12, 18, and 24 months after non‐resective periodontal surgery. Conventional radiographic and digital subtraction interpretations were performed masked, respectively, by two and three experienced examiners, according to the following categories: bone gain; bone loss; unchanged appearance; and impossible to visualize. Percent concordance and the kappa statistic value (κ) were computed.

Results: Conventional radiographic and digital subtraction interpretation images resulted in 72 decisions for each examiner. The visual interpretation of digital subtraction images by two examiners revealed the same results. The interpretation of conventional radiographic images showed a low concordance between examiners (κ <0.40) at all examinations. The concordance between subtraction radiography and conventional radiographic interpretation was also low for all examiners (κ <0.36) at all examinations. Using subtraction radiography as a reference, bone changed and bone unchanged were diagnosed correctly in 47.2% of cases by examiner A, in 43.1% by examiner B, and in 38.9% by examiner C.

Conclusion: It can be concluded that conventional radiographic interpretation is a more subjective and inaccurate method of detecting periodontal bone changes in Class II furcation defects in mandibular molars when compared with subtraction radiography. J Periodontol 2004;75:1145‐1149.
Expanded Mesh Connective Tissue Graft for the Treatment of Multiple Gingival Recessions
Authors: Çetiner Deniz , Bodur Ayşen , Uraz Ahu
Published: February 2005

Background: The connective tissue graft procedure is an effective method to achieve root coverage. Although multiple sites often need grafting, the palatal mucosa supplies only a limited area of grafting material. The expanded mesh graft provides a method whereby a graft can be stretched to cover a larger area. The aim of this study was to determine the effectiveness and the predictability of expanded mesh connective tissue graft (e‐MCTG) in the treatment of multiple gingival recessions.

Methods: Fifty‐two buccal gingival recessions were treated in 10 systemically healthy patients. Fifteen recession treated operation sites with at least three adjacent Miller Class I and/or II recessions were performed. The connective tissue graft obtained from the palatal mucosa was expanded to cover the recipient bed, which was 1.5 times larger than the graft. Clinical measurements recorded at baseline and 12 months postoperatively included gingival recession depth (RD), gingival recession width (RW), percentage root coverage (RC), probing depth (PD), width of keratinized tissue (KT), and clinical attachment level (CAL).

Results: Twelve months after surgery, a statistically significant gain in CAL (3.2 ± 0.8 mm, P <0.001) and increase in KT (1.2 ± 0.4, P <0.001) were assessed. In 80% of the treated sites, 100% RC was achieved (mean 96%).

Conclusions: The results of this study demonstrated that the use of e‐MCTG technique allowed the treatment of multiple adjacent recessions with adequate wound healing and highly predictable root coverage. This procedure can be applied favorably in treating multiple gingival recessions in one surgery. J Periodontol 2004;75: 1167‐1172.
Alendronate May Protect Against Increased Periodontitis‐Related Bone Loss in Estrogen‐Deficient Rats
Authors: Duarte Poliana Mendes , De Assis Daniel Roberto , Casati Marcio Zaffalon , Sallum Antonio Wilson , Sallum Enilson Antonio , Nociti Francisco H.
Published: February 2005

Background: The aim of this study was to evaluate the impact of alendronate (ALD) and estrogen (EST) therapies and their withdrawal on bone loss in experimental periodontitis in ovariectomized rats.

Methods: Eighty‐seven Wistar rats were divided into six groups: group 1 (N = 15): sham surgery; group 2 (N = 15): ovariectomy (OVX); group 3 (N = 15): OVX plus alendronate administration for 80 days (AT); group 4 (N = 14): OVX plus alendronate administration for 40 days (AW); group 5 (N = 14): OVX plus 17β estradiol administration for 80 days (ET); and group 6 (N = 14): OVX plus 17β estradiol administration for 40 days (EW). Twenty‐one days after ovariectomy or sham surgery, one mandibular molar was randomly assigned to receive a ligature, while the contralateral tooth was left unligated. Sixty days later, the animals were sacrificed and the specimens processed.

Results: OVX presented a direct impact on alveolar bone, regardless of plaque accumulation and significantly increased bone loss resulting from periodontitis (P <0.05). The effect of OVX on unligated sites was significantly reduced by AT, AW, and ET (P <0.05), but not by EW (P >0.05). In addition, alendronate administration (AT/AW) significantly reduced the impact of OVX on periodontitisrelated bone loss (P <0.05), while estradiol did not (P >0.05).

Conclusion: Within the limits of this study, alendronate administration, but not estrogen replacement, may protect against the impact of estrogen deficiency on alveolar bone presenting a signi‐ ficant residual effect after its withdrawal. J Periodontol 2004;75: 1196‐1202.
TT Virus Infection of Periodontal Tissues: A Controlled Clinical and Laboratory Pilot Study
Authors: Rotundo R. , Maggi F. , Nieri M. , Muzzi L. , Bendinelli M. , Prato G.P. Pini
Published: February 2005

Background: A novel single‐strand, circular DNA virus has been recently isolated and named TT virus (TTV). It has been demonstrated that peripheral blood cells harbor TTV DNA, suggesting that the virus might replicate in lymphoid cells and contribute to lymphocyte imbalances with consequent immunosuppressive effects. The purpose of this study was to investigate the prevalence of TTV DNA in healthy and periodontally compromised subjects, evaluating the presence of the virus in the gingiva and saliva, and comparing virological results with clinical data.

Methods: Twenty‐one patients (seven males and 14 females, aged 25 to 76 years) were enrolled in the study. Eleven subjects were diagnosed with moderate periodontitis, while 10 were periodontally healthy. A sample of saliva was taken from each patient before recording the periodontal data; subsequently, a gingival biopsy was performed. A real‐time polymerase chain reaction was used to quantify the presence of TTV DNA in saliva and gingival specimens.

Results: A statistically significant association was found between TTV in gingival tissue and the presence of periodontitis (P = 0.0351), while no association was observed between TTV in saliva and the presence of periodontitis (P = 0.4762).

Conclusions: A new DNA virus (TTV) was first identified in the gingival tissue and was found to be significantly associated with the presence of periodontitis. These findings need to be investigated in further studies. J Periodontol 2004;75:1216‐1220.
Influence of Parameters on Root Surface Roughness Following Treatment With a Magnetostrictive Ultrasonic Scaler: An In Vitro Study
Authors: Folwaczny Matthias , Merkel Ute , Mehl Albert , Hickel Reinhard
Published: February 2005

Background: This in vitro study aimed to evaluate the influence of different parameters, i.e., lateral force, instrument power setting, and the shape of the working tip, on the roughness of root surfaces following treatment with a magnetostrictive ultrasonic scaling device.

Methods: The study sample comprised a total of 102 extracted human molars, premolars, canines, and incisors. The samples were randomly divided into 10 equal units of 10 each for treatment with the ultrasonic device at a lateral force of 0.5 N and 2.0 N, low and high instrument power setting, and with a straight and angulated shaped working tip. Twenty samples were treated manually using curets at a lateral force of 0.5 N and 2.0 N. Two samples were left untreated as controls. The mean (Ra) and maximum (Rmax) surface roughness of each sample was recorded. The statistical analysis was performed using analysis of variance (three‐way ANOVA) at a level of significance of 5% (P <0.05).

Results: The mean surface roughness (±SD) using different parameters ranged from 0.6 ± 0.1 μm to 1.8 ± 0.3 μm. The maximum surface roughness (±SD) was between 4.8 ± 1.3 μm and 17.2 ± 4.3 μm. The mean surface roughness (±SD) for samples treated with curets at a lateral force of 0.5 N was 0.5 ± 0.0 μm and 0.4 ± 0.1 μm at 2.0 N. The maximum surface roughness (±SD) was 3.7 ± 0.8 μm at 0.5 N and 3.9 ± 1.4 μm at 2.0 N.

Conclusions: The findings of the present study indicate that the shape of the working tip and the lateral force significantly influence the mean and maximum surface roughness of root surfaces treated with a magnetostrictive ultrasonic scaling device. At any specific parameter, the surface roughness was signifi‐ cantly higher for the ultrasonic scaling device as compared to the hand curet. J Periodontol 2004;75:1221‐1226.
Effect of the Vertical and Horizontal Distances Between Adjacent Implants and Between a Tooth and an Implant on the Incidence of Interproximal Papilla
Authors: Gastaldo Jose Fabio , Cury Patricia Ramos , Sendyk Wilson Roberto
Published: February 2005

Background: The interproximal dental papilla is considered an essential component of the anterior and posterior regions of the maxilla and mandible. The absence of this structure has esthetic and phonetical consequences and lateral food impaction problems occur with the implant‐supported prosthesis. The aims of the present study were to: 1) evaluate the effect of the vertical and horizontal distances between adjacent implants (group 1) and between a tooth and an implant (group 2) on the presence of the interproximal dental papilla; and 2) determine whether the interaction between the vertical and horizontal distances might be associated with the incidence of the papilla.

Methods: In 48 patients, 96 interproximal sites in group 1 and 80 in group 2 were examined. The distance from the base of the contact point to the bone crest (D1), the distance between tooth and implant or between two implants (D2), and the distance from the base of the contact point to the tip of the papilla (D3) were measured.

Results: In both groups, when D2 was 3, 3.5, or 4 mm, the papilla was present most of the time (P <0.05), and when D2 was 2 or 2.5 mm, the papilla was absent 100% of the time (P <0.05). Further, in group 2, when D1 was between 3 and 5 mm, the papilla was present most of the time (P <0.05). However, in Group 1, only when D1 was 3.0 mm was the papilla present most of the time (P <0.05). For both groups, analysis of the interaction between D1 and D2 showed that when D2 was ≤2.5 mm, the papilla was absent; otherwise, when D2 was ≥3 mm, there was an interaction between D1 and D2.

Conclusions: We conclude that the ideal distance from the base of the contact point to the bone crest between adjacent implants is 3 mm and, between a tooth and an implant, 3 mm to 5 mm. The ideal lateral spacing between implants and between tooth and implant is 3 mm to 4 mm. Further, there is an interaction between horizontal and vertical distances when the lateral spacing is greater than 3 mm. J Periodontol 2004;75:1242‐1246.
The Role of Parathyroid Hormone‐Related Protein in the Regulation of Osteoclastogenesis by Cementoblasts
Authors: Boabaid Fernanda , Berry Janice E. , Koh Amy J. , Somerman Martha J. , McCauley Laurie K.
Published: February 2005

Background: Parathyroid hormone‐related protein (PTHrP) promotes osteoclastogenesis by inhibiting expression of osteoprotegerin (OPG), a decoy receptor for the receptor activator of nuclear factor kappa B (RANK), and by enhancing production of RANK ligand (RANKL) by osteoblasts. However, little is known regarding the role of PTHrP in regulating cementoblast‐mediated osteoclastogenesis.

Methods: This study determined the impact of PTHrP on osteoclastogenesis using: 1) OCCM‐30 (immortalized murine cementoblasts), 2) RAW 264.7 cells (murine myeloid cells), or 3) OCCM‐30 plus RAW 264.7 cells. Cells were treated with PTHrP (1‐34), RANKL, or PTHrP and RANKL combined. Enzyme‐linked immunosorbent assays (ELISAs) for OPG and RANKL were performed on media and cell lysates, and tartrate‐resistant acid phosphatase (TRAP) and mRNA detection for the osteoclast associated receptor (OSCAR) were performed.

Results: The highest numbers of TRAP‐positive cells and cells expressing OSCAR were found in the RAW cell group treated with either RANKL alone or RANKL and PTHrP. TRAP‐positive cells were fewer when OCCM cells were co‐cultured with RAW, but the greatest numbers were still with both PTHrP and RANKL. OPG levels were highest from OCCM cells and PTHrP decreased these levels. In contrast, RANKL levels were low in OCCM cell lysates and PTHrP increased RANKL. In vivo studies also revealed high osteoclastic activity surrounding developing teeth in mice administered PTH.

Conclusions: These results demonstrate that PTHrP influences the balance of OPG and RANKL production by cementoblasts, and further indicate that this effect, in the context of surrounding cells, might have a significant impact on osteoclastogenesis, root resorption, and tooth eruption. J Periodontol 2004;75:1247‐1254.
The Comparative Effect of Ultrasonic Scalers on Titanium Surfaces: An In Vitro Study
Authors: Sato Shuichi , Kishida Mamoru , Ito Koichi
Published: February 2005

Background: Professional maintenance is as important for patients with dental implants as it is for patients with natural teeth. However, no proper maintenance instruments have been available for implant patients. The purpose of this in vitro study was to compare the effects of a new ultrasonic scaler (VR), a conventional ultrasonic scaler (SP), and a plastic scaler (PS) on titanium surfaces.

Methods: To simulate subgingival conditions, the implant healing abutments were connected to acrylic resin blocks with artificial gingiva using silicon impression material. The abutments were painted with ink as an artificial form of debris. The ink was removed with the VR, SP, or PS scaler for 60 seconds under standardized conditions, and the removal rate was calculated. The roughness of the abutment surface was measured with a profilometer and observed by scanning electron microscopy (SEM).

Results: The removal rate using the VR and SP scalers was higher than that using the PS scaler. No significant differences in the surface roughness or SEM observations were found among the VR, SP, or PS scalers.

Conclusions: In this preliminary study, the new ultrasonic scaler and conventional ultrasonic scaler were shown to be useful for removing artificial debris and produced no significant damage to titanium surfaces compared to plastic scalers. We concluded that new and conventional ultrasonic scalers with a non‐metal tip would be suitable for implant maintenance. J Periodontol 2004;75:1269‐1273.