bluuebunny/crossref_metadata_2025 huggingface dataset:
Addition of Human Recombinant Bone Morphogenetic Protein‐2 to Inactive Commercial Human Demineralized Freeze‐Dried Bone Allograft Makes An Effective Composite Bone Inductive Implant Material
Authors: Schwartz Zvi , Somers Ann , Mellonig James T. , Carnes David L. , Wozney John M. , Dean David D. , Cochran David L. , Boyan Barbara D.
Published: March 2012

Commercial preparations of human demineralized freeze‐dried bone allograft (DFDBA) vary in their ability to induce new bone formation. This study tested the hypothesis that inactive DFDBA can be used as an effective carrier of recombinant human bone morphogenetic protein2 (rhBMP‐2). Two batches of active DFDBA were used as controls. Two batches of DFDBA, previously shown to be inactive, were treated with vehicle or with 5 or 20 pg rhBMP‐2 and implanted into the calf muscle of male Nu/Nu (nude) mice. Each mouse received one implant in each hind limb, both of which were of the same formulation, resulting in 8 groups of 4 mice per group: active DFDBA batch A, active DFDBA batch B, inactive DFDBA batch A, inactive DFDBA batch B, inactive DFDBA batch A plus 5 μg rhBMP‐2, inactive DFDBA batch A plus 20 pg rhBMP‐2, inactive DFDBA batch B plus 5 μg rhBMP‐2, and inactive DFDBA batch B plus 20 μg rhBMP‐2. After 56 days, the implants were removed and histologically examined. A semiquantitative bone induction index was calculated based on the amount of new bone covering each histological section. Histomorphometry was also used to evaluate the area of new bone formed and the area of residual implant material. The results showed that active DFDBA induces new bone formation, whereas inactive DFDBA does not. Addition of rhBMP‐2 to inactive DFDBA results in new bone formation with a bone induction index comparable to that of active DFDBA. Histomorphometric analysis, however, revealed that the rhBMP‐2‐containing implants caused a dose‐dependent increase in new bone area that exceeded that induced by active DFDBA. At the highest concentration of rhBMP‐2, bone formation was exuberant. rhBMP‐2 also caused the resorption of residual implant material to levels comparable to that seen in sites treated with active DFDBA, suggesting that this growth factor may regulate resorptive cells either directly or indirectly. This study shows that addition of rhBMP‐2 to inactive DFDBA provides reproducible, consistent bone induction, and suggests that inactive commercial preparations may contain inadequate amounts of BMP to cause bone induction compared to active preparations. J Periodontol 1998;69:1337–1345.
Evaluation of a Bioactive Glass Alloplast in Treating Periodontal Intrabony Defects
Authors: Ong Marianne M.A. , Eber Robert M. , Korsnes Maria I. , MacNeil R. Lamont , Glickman Gerald N. , Shyr Yu , Wang Hom‐Lay
Published: March 2012

This study evaluated the use of bioactive glass (BG) for repairing/regenerating periodontal intrabony defects. Fourteen systemically healthy patients participated. Each patient had 2 contralateral sites with ≥ 6 mm clinical probing depth and radiographic evidence of an intrabony defect. One defect was treated with flap debridement plus BG (test) and the other with flap debridement alone (control). Baseline measurements included gingival index (GI), plaque index (PI), position of the free gingival margin (S/FGM), clinical attachment level (CAL), probing depth (PD), and mobility. At the time of surgery and at surgical reentry (9 to 13 months later), hard tissue measurements included: stent to defect base, bone crest to defect base, and defect width at the bone crest. One‐way repeated ANOVA was used to analyze the treatment effect. Friedman's test was used to detect any significant changes of GI, PI and mobility at different time periods (baseline, 3 months, 6 months, and reentry). For multivariate analysis, the random coefficients mixed effect model was applied to adjust the intra‐correlation effect. Both treatments resulted in decreased PD and gain of CAL. These changes were only significant (P < 0.05) for the BG treated sites (PD reduction = 1.24 ± 0.43 mm, CAL gain = 0.87 ± 0.38 mm) from baseline. Defect fill was significant for test (1.1 ± 0.4 mm) and control (1.4 ± 0.4 mm) alike (P < 0.01). Although BG treated sites had more PD reduction and CAL gain than debridement only controls, there were no statistically significant differences between groups for any parameter measured. Further studies are required to clarify the beneficial effects, if any, of BG alloplast in treating periodontal intrabony defects. J Periodontol 1998;69:1346–1354.
Clinical and Microbiologic Effects of Adjunctive Antibiotics in Treatment of Localized Juvenile Periodontitis. A Controlled Clinical Trial
Authors: Tinoco Eduardo M.B. , Beldi Maria I. , Campedelli Flavia , Lana Marcia , Loureiro Carlos A. , Bellini Hamilton T. , Rams Thomas E. , Tinoco Neyde M.B. , Gjermo Per , Preus Hans R.
Published: March 2012

The aim of this study was to assess the clinical and microbiologic effects of the combination of amoxicillin and metronidazole therapy as an adjunct to mechanical treatment in the management of localized juvenile periodontitis. Twenty‐five localized juvenile periodontitis (LJP) patients from a Brazilian population were randomly allocated into an experimental group receiving mechanical treatment and antibiotics, and a control group receiving mechanical treatment and placebo. Clinical and radiographic assessments, as well as microbiologic sampling for Actinobacillus actinomycetem.comitans, were performed at baseline and one year after the end of the treatment. At the termination of the study A. actinomycetemcomitans could be isolated from the oral cavity of all patients in the control group who harbored the bacterium at baseline and in 4 out of 8 patients in the experimental group. Both treatment modalities resulted in significant benefit on an individual basis. The experimental group, however, displayed better results than did the control group regarding gingival index (GI), probing depth (PD), clinical attachment level (CAL), and radiographic analysis of crestal alveolar bone mass, but not with respect to plaque index (PI). No serious adverse effects of the antibiotic treatment were observed in the present study. J Periodontol 1998;69:1355–1363.
The Prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus in Humans 1 Year After 4 Randomized Treatment Modalities
Authors: Shiloah Jacob , Patters Mark R. , Dean John W. , Bland Paul , Toledo Gilbert
Published: March 2012

The relationship between probing attachment changes in treated periodontal pockets and the prevalence of selected periodontal pathogens was assessed in 10 patients with adult periodontitis 1 year following randomized therapy. All patients had at least 1 tooth in each quadrant with an inflamed pocket of probing depth ≥5 mm and clinical attachment loss and harbored at least one of the following 3 major periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, or Bacteroides forsythus. The number of target organisms per site was determined preoperatively; at 1 week; and at 1, 3, 6, and 12 months postoperatively utilizing DNA probes. The following clinical parameters were measured and recorded preoperatively and at 1, 3, 6, and 12 months post‐treatment: gingival fluid flow, gingival index, plaque index, probing depth, probing attachment level, gingival recession, and bleeding on probing. One quadrant in each patient was randomly assigned to 1 of the following 4 treatments: 1) scaling and root planing; 2) pocket reduction through osseous surgery and apically‐positioned flap; 3) modified Widman flap; and 4) modified Widman flap and topical application of saturated citric acid at pH 1 for 3 minutes. All 4 treatments were rendered in one appointment using local anesthesia. No postoperative antibiotics were used, but patients rinsed with 0.12% Chlorhexidine for the first 3 months postoperatively and received a prophylaxis every 3 months. This investigation revealed: 1) 30.0% of the sites were infected by at least 1 species at 3, 6, and 12 months postoperatively. 2) Failing sites were infected by a high number of both Pg and Bf. These sites had a mean of 24.2 ± 9.0 × 103Pg and 93.1 ± 42.0 × 103 Bf, while stable sites had a mean of 6.8 ± 0.5 × 103 Pg and 7.2 ± 1.2 × 103 Bf (P = 0.06 and P = 0.05, respectively). 3) The infected sites lost significantly more mean clinical attachment at 12 months (1.5 ± 0.5 mm compared to a loss of 0.2 ± 0.3 mm for uninfected sites, P = 0.017). 4) The infected sites had a significantly greater BOP (67 ± 14% versus 25 ± 8% for uninfected sites at 12 months, P = 0.012). 5) The choice of treatment modality did not affect the prevalence of the target species at 1 year post‐treatment. These results suggest that prevalence of microbial pathogens negatively affects the 1 year outcome of periodontal surgical and nonsurgical therapy. J Periodontol 1998;69:1364–1372.
A Comparison of 2 Root Coverage Techniques: Guided Tissue Regeneration With a Bioabsorbable Matrix Style Membrane Versus a Connective Tissue Graft Combined With a Coronally Positioned Pedicle Graft Without Vertical Incisions. Results of a Series of Consecutive Cases
Authors: Harris Randall J.
Published: March 2012

Root coverage procedures have become an important part of periodontal therapy. The purpose of this study was to compare 2 techniques, 1) guided tissue regeneration (GTR) with a bioabsorbable polylactic acid softened with citric acid ester membrane and 2) the connective tissue graft combined with a coronally positioned pedicle graft without vertical incisions. The GTR procedure produced a mean root coverage of 92.3% and the connective tissue graft combined with a coronally positioned pedicle graft, 95.0%. This difference was not statistically significant. Both procedures produced similar reductions in recession depth, recession width, and probing depth. The connective tissue graft combined with a coronally positioned pedicle graft resulted in a greater increase in the amount of keratinized tissue. Based on this study, both procedures can result in statistically similar amounts of mean root coverage, but the results are not identical. In most cases, the connective tissue with coronally positioned pedicle graft produced a more bulky result than guided tissue regeneration. Therefore, the procedures are not interchangeable. J Periodontol 1998;69:1426–1434.
Diabetes Prevents Periodontitis‐Induced Increases in Gingival Platelet Derived Growth Factor‐B and Interleukin 1‐Beta in a Rat Model
Authors: Doxey D.L. , Cutler C.W. , Iacopino A.M.
Published: March 2012

Periodontitis is a chronic inflammatory disease characterized by a progression that is very much dependent on host response. The gingiva can be considered to be in a constant state of wounding (pathologic wounding by bacterial plaque) and a constant state of maintenance/repair. In this context, any metabolic disturbance in the host which compromises tissue repair/wound healing will exacerbate the progression of periodontitis. Diabetes presents an interesting example because two major complications of diabetes are delayed wound healing and periodontitis. Our previous studies indicate that delayed wound healing and periodontitis may be manifestations of a general systemic deficit in diabetes involving alteration of macrophage cytokine gene expression. The present study was designed to determine whether: 1) diabetes‐induced metabolic alterations affect gingival cytokine levels; and 2) diabetes‐induced metabolic alterations modify the gingival cytokine profile in periodontitis. Sprague‐Dawley rats (N = 12/group) were injected with streptozotocin (65 mg/kg) into the tail vein to induce diabetes (defined by blood glucose levels > 250 mg/dl) or received the injection vehicle or no treatment as controls. Periodontitis was induced in additional groups of diabetic and control rats by gavage with Porphyromonas gingivalis A7436. After 90 days, serum glucose was analyzed to document diabetes; alveolar bone level was measured to document severity of periodontitis; gingiva was harvested circumferentially from the first and second molars; and cytokines in gingival homogenates were assayed by ELISA using commercial kits. Cytokine levels were expressed as mean ± SEM pg/μg protein. Diabetes alone did not alter the gingival cytokine profile for platelet‐derived growth factor B (PDGF‐B), interleukin 1‐beta (IL‐1β), transforming growth factor‐beta (TGF‐β), and tumor necrosis factor‐alpha (TNF‐α). Periodontitis alone demonstrated a significant increase (P < 0.05) in levels of PDGF‐B and IL‐1β. Diabetes superimposed on periodontitis prevented these increases. Thus, diabetes‐induced metabolic alterations do not affect gingival cytokine levels per se; however, they do alter the normal host response to periodontitis through blockage of periodontitis‐induced increases in PDGF‐B and IL‐1β. J Periodontol 1998;69:113–119.
Mucogingival Versus Guided Tissue Regeneration Procedures in the Treatment of Deep Recession Type Defects
Authors: Zucchelli G. , Clauser C. , De Sanctis M. , Calandriello M.
Published: March 2012

The objective of the study was to compare the clinical efficacy of 3 surgical approaches in the treatment of deep recession type defects. Fifty‐four (54) gingival recessions ≥ 5 mm were randomly assigned, to 1 of the 3 treatment groups by blocking the prognostic variables. The first group was treated with a guided tissue regeneration (GTR) procedure using a bioabsorbable membrane, the second with non‐resorbable membrane, and the third with a mucogingival surgical approach consisting of a connective tissue graft combined with a coronally advanced flap (bilaminar technique). No differences, in terms of baseline oral hygiene and defect characteristics, were observed among the 3 groups showing an effective blocking approach. The 1‐year results indicated that 1) all treatment approaches resulted in clinically significant root coverage and attachment gain; 2) a statistically significant treatment effect (P = 0.012, ANOVA) was observed comparing the bioabsorbable (4.9 ± 0.3 mm), the non‐resorbable (4.5 ± 0.8 mm), and the bilaminar (5.3 ± 0.7 mm) groups, in terms of root coverage; 3) the difference in terms of root coverage between the bilaminar and the non‐resorbable membrane groups was statistically significant while differences between the 2 GTR groups or between the bilaminar and the bioabsorbable membrane groups did not reach statistical value; 4) the 95% confidence intervals for the proportions of complete successes showed a similar pattern; 5) no statistical difference was demonstrated in the amount of attachment gain among the 3 groups (P = 0.73, ANOVA). A regression model showed that the amount of root coverage was significantly affected by the initial recession depth, the procedure and smoking habits: a poorer root coverage result is expected in case of shallow recession type defects, when either bioabsorbable (P < 0.05) or non‐resorbable (P < 0.001) membranes are used instead of a bilaminar technique and if the patient smokes (P < 0.01). It was concluded that the mucogingival bilaminar technique is at least as effective as GTR procedures in the treatment of gingival recession ≥ 4 mm and thus recession depth is not the parameter which influences the selection of the surgical procedure. J Periodontol 1998;69:138–145.
Impact of Endodontic Conditions on Marginal Bone Loss
Authors: Miyashita Hiroshi , Bergenholtz Gunnar , Gröndohl Kerstin , Wennström Jan L.
Published: March 2012

This study was undertaken to examine the extent to which the marginal alveolar bone may be influenced by the condition of the dental pulp. A total of 115 pairs of contralateral teeth were observed in 87 patients (25 to 45 years old) in which the test tooth, but not the control tooth, was either endodontically treated or not treated but with a periapical radiolucency. The distance from the cemento‐enamel junction to the marginal bone level was measured using intraoral radiographs. The condition of the endodontic filling, the periapical status, and the presence of root canal post were also assessed. With clinical parameters similar between teeth in the two groups in terms of visible plaque, bleeding on probing, probing depth, and attachment level, the results showed a somewhat (mean value 0.1 mm; SD 0.7) larger reduction of the alveolar bone support in test than control teeth. This difference was not statistically significant on a patient level. Hence, this study failed to demonstrate a correlation between a reduced marginal bone support and endodontic status. J Periodontol 1998;69:158–164.
The Effect of Smoking on Individuals With Minimal Periodontal Destruction
Authors: Gunsolley J.C. , Quinn S.M. , Tew J. , Gooss C.M. , Brooks C.N. , Schenkein H.A.
Published: March 2012

Recent studies have demonstrated that smoking is associated with periodontal destruction. The majority of these studies have focused on periodontal disease groups with moderate or severe periodontal destruction. Additionally, there have been few reports investigating the relationship between smoking and gingival recession. The goal of this report was to investigate the effect of smoking on periodontal destruction and recession in subjects with minimal or no interproximal attachment loss. This is a cross‐sectional study of 142 non‐smoking subjects and 51 smoking subjects. Subjects could have no more than one tooth with a site of interproximal attachment loss ≥2 mm. Subjects could, however, have attachment loss associated with recession. For three different methods of summarizing attachment loss measurements at a subject level, including average attachment loss, percentage of teeth with one site of 2 mm of attachment loss, and the percentage of teeth with one site of 5 mm of attachment loss, smoking subjects had approximately twice as much attachment loss than their non‐smoking counterparts. Smoking subjects also had significantly greater recession (P < 0.05) (0.056 ± 0.017 mm) than non‐smoking subjects (0.025 ± 0.005 mm). Recession sites occurred primarily on the facial surface of maxillary molars and bicuspids and mandibular central incisors and bicuspids. The results suggest a strong association between smoking and both attachment loss and recession in subjects who have minimal or no periodontal disease. J Periodontol 1998;69:165–170.
Microbiota Associated With Experimental Peri‐Implantitis and Periodontitis in Adult Macaca mulatta Monkeys
Authors: Eke Paul I. , Braswell Laura D. , Fritz Michael E.
Published: March 2012

This study examines the microbiota associated with the progression of experimental peri‐implantitis and periodontitis induced concurrently in partially edentulous adult monkeys. Root‐form and plate‐form implants with fixed prosthesis in place for at least 12 months and their corresponding opposite molar teeth were ligated for 6 months. The microbiota in plaque around these ligated dental implants and molars were studied at 0, 1, 2, 3, and 6 months post‐ligation. Plaque samples were analyzed by dark‐field microscopy and selective and non‐selective culture. Putative periodontal pathogens were detected as a major component of the microbiota cultured from plaque samples obtained from experimental peri‐implantitis sites. Overall, the types and relative proportions of putative periodontal pathogens in plaque associated with ligature‐induced peri‐implantitis and ligature‐induced periodontitis were similar. Only levels of anaerobic Actinomyces and spirochetes were significantly different between both sites. Spirochete levels were significantly higher at peri‐implantitis sites when compared with levels at periodontitis sites after 6 months, and spirochete levels increased significantly between 0 and 6 months post‐ligation at implant sites. Levels of spirochetes correlated significantly with probing depth and bone loss at peri‐implantitis sites. Overall, Actinomyces levels were higher at periodontitis sites. Porphyromonas species were not detected continuously as part of the peri‐implantitis microbiota. In conclusion, this study finds that the microbiota associated with the progression of experimental periimplantitis and periodontitis occurring concurrently in partially edentulous mouths are similar. J Periodontol 1998;69:190–194.
Cytoskeletal Actin Reorganization in Neutrophils From Patients With Localized Juvenile Periodontitis
Authors: Champagne Catherine M. , Vaikuntam Jaywanth , Warbington Martha L. , Rose Lynda , Daniel Michael A. , Van Dyke Thomas E.
Published: March 2012

Localized juvenile periodontitis (LJP) is an early‐onset periodontal disease associated with a polymorphonuclear neutrophil (PMN) defective migratory response. Kinetics of actin polymerization–depolymerization determine the shape changes occurring in the plasma membrane‐associated cytoskeleton and provide the driving force for directed cell migration (chemotaxis). Therefore, we investigated the relation between an abnormality in LJP PMN chemotaxis and an altered reorganization of the actin filament network. PMNs isolated from peripheral blood of LJP patients (n= 14) and matching control subjects (n= 12) were evaluated for random and directed migration in a Boyden chamber assay, and the kinetics of actin polymerization were studied by flow cytometry. Three groups of LJP patients could be distinguished on the basis of their PMN–chemotactic response compared to their matched control: depressed (n= 6), normal (n= 4), and elevated (n=4). The abnormal (depressed or elevated) chemotaxis was generally not related to abnormal random migratory response, except for two patients. Since the kinetics of formyl–methionyl–leucyl–phenylalanine–induced F‐actin response were highly variable from one subject to another, means were calculated at each timepoint with the values obtained from each group of subjects and compared by a general factorial design analysis. No statistically significant differences were detected between the control group and the LJP patient group. Furthermore, the data did not show a correlation between the kinetics of actin polymerization–depolymerization and the abnormal chemotactic response observed in LJP PMNs. Hence, the chemotaxis defect in LJP PMN appears to be mediated by signaling events that carry their effect independently of an intact cytoskeleton. J Periodontol 1998;69:209–218.
Treatment of Intrabony Defects by Different Surgical Procedures. A Literature Review
Authors: Laurell Lars , Gottlow Jan , Zybutz Michael , Persson Rutger
Published: March 2012

This article reviews studies presented during the last 20 years on the surgical treatment of intrabony defects. Treatments include open flap debridement alone (OED); OFD plus demineralized freeze‐dried bone allograft (DFDBA), freeze‐dried bone allografts (FDBA), or autogenous bone; and guided tissue regeneration (GTR). The review includes only studies that presented baseline and final data on probing depths, intrabony defect depths as measured during surgery, clinical attachment level (CAL) gain, and/or bone fill. Some reports were case studies and some controlled studies comparing different treatments. In order to assess what can be accomplished in terms of pocket reduction, clinical attachment level gain, and bone fill with the various treatment modalities, data from studies of each treatment category were pooled for meta‐analysis in which the data from and power of each study were weighted according to the number of defects treated. In addition, where there were data for each individual defect treated, these were used for simple regression analysis evaluating the influence of intrabony defect depth on treatment outcome in terms of CAL gain and bone fill. This was done in an effort to assess some predictability of the outcome of the various treatments. OFD alone resulted in limited pocket reduction, CAL gain averaged 1.5 mm and bone fill 1.1 mm. Bone fill, but not CAL gain, correlated significantly to the depth of the defect (R = 0.3; P < 0.001), but the regression coefficient was only 0.25. OFD plus bone graft resulted in limited pocket reduction. CAL gain and bone fill averaged 2.1 mm. Bone fill showed a somewhat stronger correlation to defect depth than following OFD alone (R = 0.43; P < 0.001) with a regression coefficient of 0.37. GTR resulted in significant pocket reduction, CAL gain of 4.2 mm, and bone fill averaging 3.2 mm. CAL gain and bone fill correlated significantly (P < 0.001) to defect depth (R = 0.52 and 0.53 respectively) with the largest regression coefficients (0.54 and 0.58 respectively) among the three treatment modalities. By comparing outcomes following the various treatments it became obvious that to benefit from GTR procedures, the intrabony defect has to be at least 4 mm deep. J Periodontol 1998;69:303–313.
Root Surface Characteristics of Primary Teeth From Children With Prepubertal Periodontitis
Authors: Bimstein Enrique , Wagner Mark , Nauman Robert K. , Abrams Ronald G. , Shapiro Lior
Published: March 2012

This study describes the histologic characteristics of root surfaces of primary teeth from children with prepubertal periodontitis (PP). Fifteen primary teeth from 4 children with PP, and 2 control primary teeth from 2 healthy children were examined. Light microscopy revealed normal root surfaces in the control teeth. In contrast, the PP specimens revealed bacteria inside dentin tubules or covering cementum, a cuticle, or resorbed dentin; normal, wider than normal, or hypoplastic cementum; resorption lacunae with various depths; aplastic root resorption; alternate resorption and repair; and active repair. No cementoclasts were found in the resorption lacunae. Scanning electron microscopy revealed intrabony and suprabony root areas, and a “plaque free zone” (PFZ). Colonies of filaments were evident at the cemento‐enamel junction (CEJ). The suprabony root surfaces had resorption lacunae, isolated short rods, calculus, colonies of filaments, or colonies composed by an heterogeneous bacterial population. The coronal boundary of the PFZ was the border of a sheet‐like structure, which included isolated rods or filaments. At the PFZ, isolated filaments and rods, and a fibril matrix were evident. The apical boundary of the PFZ consisted of bundles of soft tissue remnants or the insertion of the periodontal fibers. The intrabony surfaces were mostly covered by soft tissue, which included isolated filaments and short rods. Resorption lacunae with or without soft tissue were also evident in this area. Crystals of calcium Oxalate dihydrate and erythrocytes in distinct forms were found at various root areas. The present findings are different from those previously reported for hypophosphatasia specimens. J Periodontol 1998;69:337–347.
Evaluating the Burst Hypothesis at a Site‐Specific Level Using the Lack‐of‐Fit Test
Authors: Hujoel P.P. , Leroux B.G.
Published: March 2012

It has been hypothesized that periodontal disease progresses by means of sudden losses of periodontal attachment surface area. Obtaining reliable tests of this burst hypothesis has proven to be difficult; the signal (true model of disease progression) often gets lost in the noise. The purpose of this study was to determine how reliably we could distinguish sudden changes from linear disease progression at a site using a time series of clinical attachment levels. Specifically, the following question was investigated: If, in reality, disease progresses by means of sudden changes in clinical attachment level (bursts), and a linear model is fitted to these data, what is the likelihood of rejecting the linear model using the lack‐of‐fit test? This likelihood was determined as a function of the probing measurement error (range: 0.2 to 1.0 mm) and the number of clinical examinations over time. The results suggested that bursts of 2 mm or smaller cannot be reliably distinguished from linear disease progression using the lack‐of‐fit test, except under unusual clinical circumstances. Under typical clinical circumstances, burst sizes needed to be 3 to 5 mm in order to be reliably distinguished from linear disease progression. These results are probably overly optimistic. The ability to verify the burst hypothesis at the site level is likely to be even less than our results indicate because of various assumptions that were required. We conclude that the lack‐of‐fit test will reliably reject the linear model at a site‐specific level only if true disease progresses in such a fashion that a handful of sudden changes leads to a tooth mortality event. J Periodontol 1998;69:357–362.
Cervical Root Resorption Associated With Guided Tissue Regeneration: A Case Report
Authors: Blomlöf Leif , Lindskog Sven
Published: March 2012

Root surface resorption, ankylosis (replacement resorption) and alveolar bone resorption are not uncommon sequelae to periodontal healing in both animal and human trials whether the treatment objective is regenerative, preventive, or conservative. The present report describes a case with progressive cervical root resorption in a patient who received periodontal regenerative treatment with guided tissue regeneration (GTR). A 46‐year‐old woman was referred for treatment of severe periodontitis. Remaining radiographie attachment was less than 50%. Following a period of 18 months, during, which non‐surgical and surgical therapies were performed, angular defects were diagnosed on radiographs and recurrent bleeding periodontal pockets (6 mm) were found in the proximal areas of 24 and 25. Root caries was not present. Periodontal surgery with GTR was performed in this area. No immediate postsurgical complications were noted. Two years later, clinical and radiographic examinations revealed gingival recession with bleeding periodontal pockets (6 mm) which had partly uncovered severe proximal cervical resorptions in 25. Root surface caries was not present. Following surgical inspection, the root of 25 was removed. The root was subsequently prepared for histological analysis. Resorption cavities covered almost the entire cervical proximal surface of the root above intact infracrestal cementum and were covered by numerous CD68+, both mononuclear and multinucleated cells. In a central area as indicated on the radiographs, the cavities penetrated into the root canal. There was no evidence of root caries. J Periodontol 1998;69:392–395.
Evaluation of Antimicrobial Efficacy and Release Pattern of Tetracycline and Metronidazole Using a Local Delivery System
Authors: Somayaji B.V. , Jariwala Urmila , Jayachandran P. , Vidyalakshmi K. , Dudhani Rajesh V.
Published: March 2012

The present study compared the effectiveness of two antimicrobials, tetracycline and metronidazole, in reducing subgingiyal microorganisms in periodontal pockets using an ethyl cellulose strip as the delivery medium. The study involved 30 patients, with a minimum of 3 periodontal pockets with probing depths > 6 mm throughout the oral cavity. Patients were given supragingival scaling and then divided into 5 groups, depending on the length of time the medication was in place. Sites were marked for tetracycline, metronidazole, and placebo. Sites were wiped and isolated, and baseline microbiology samples were taken for Gram staining and culture methods. After treatment, subgingival microbiological samples were taken again. The ethyl cellulose strips were removed and analyzed for any remaining drug. Results showed that tetracycline and metronidazole can both be applied locally to periodontal sites using ethyl cellulose strips and markedly suppress the subgingival bacteria over a period of several days. The tetracycline showed a faster release; however, the metronidazole required a lesser concentration to achieve complete reduction of the subgingival flora. J Periodontol 1998;69:409–413.
The Influence of Direct Composite Additions for the Correction of Tooth Form and/or Position on Periodontal Health. A Retrospective Study
Authors: Peumans M. , Van Meerbeek B. , Lambrechts P. , Vanherle G. , Quirynen M.
Published: March 2012

The aim of this in vivo study was to evaluate the influence of 5‐ to 6‐year‐old direct composite additions on the marginal periodontal tissues. Composite additions were directly placed on 79 intact maxillary anterior teeth in 19 patients (12 to 19 years) by one operator using an ultrafine midway‐filled densified resin composite. All patients were recalled 5 to 6 years later for a periodontal evaluation. Plaque index, gingivitis index, and probing depth were measured at the buccal‐approximal sites of all unilaterally restored teeth (n = 51). An intra‐individual comparison was made between the periodontal health of the treated versus the intact sites. The plaque index (P = 0.029) and gingivitis index (P = 0.008) were significantly higher for the treated sites compared to the intact sites. The difference in probing depth nearly reached the level of significance (P = 0.059). In conclusion, 5‐to 6‐year‐old direct composite additions have a negative influence on marginal periodontal health, which consisted of increased plaque retention, gingival inflammation, and periodontal destruction. J Periodontol 1998;69:422–427.
Tumor Necrosis Factor Alpha Production by Oral Leukocytes: Influence of Tumor Necrosis Factor Genotype
Authors: Galbraith Gillian M. P. , Steed R. Britt , Sanders John J. , Pandey Janardan P.
Published: March 2012

Tumor necrosis factor alpha (TNF‐α) is a proinflammatory cytokine that is thought to play a role in the pathogenesis of periodontal disease. TNF‐α production is regulated by many factors, including certain alleles of TNF gene polymorphisms. In the present study, TNF genotypes of 3 bi‐allelic polymorphisms were determined in 32 Caucasian patients with adult periodontitis and 32 orally‐healthy matched controls, and correlated with TNF‐α production by oral polymorphonuclear leukocytes (PMN). No differences in distribution of TNF alleles of the −238, −308, or +252 gene polymorphisms were observed between patients and controls or between patients with different disease severity. However, the level of TNF‐α production by oral PMN correlated with the TNF‐α−308 genotype in patients with adult periodontitis, with increased production found in patients with the T1,2 genotype (t‐test; P = 0.037). When cytokine production was examined in patients according to disease severity, an association between the T1,2 genotype and increased production was observed only in patients with advanced disease (t‐test; P = 0.05). These findings suggest that further studies are warranted to determine if the TNF genotype is a risk factor for severity of disease in adult periodontitis. J Periodontol 1998;69:428–433.
Blood Contamination of the Aerosols Produced by In Vivo Use of Ultrasonic Sealers
Authors: Barnes James B. , Harrel Steven K. , Rivera‐Hidalgo Francisco
Published: March 2012

Disease transmission and barrier techniques during dental treatment have been areas of recent concern in dentistry. Ultrasonic sealers are known to produce aerosols, and these aerosols are often produced from areas of significant disease activity, including bleeding. This study was performed to determine if these aerosols contain blood from the gingival sulcus. Forty areas consisting of two contiguous periodontally involved teeth (probing depth of at least 5 mm on one site of each tooth) were scaled subgingivally with an ultrasonic sealer for 30 seconds. A high volume evacuator (HVE) tip was positioned 3 to 5 cm away from the operating site and utilized to capture the aerosols produced. The water remaining in and on the HVE tube was tested for occult blood by the guiac resin method. Gingival index, mean probing depth, presence of bleeding with scaling, and presence of visible blood in the HVE tip were recorded. All 40 test sites showed a positive result for blood in the captured aerosols despite the wide variation in the measured parameters. It may be concluded that subgingival scaling on periodontally involved teeth with ultrasonic sealers would be expected to produce aerosols containing blood. J Periodontol 1998;69:434–438.
Clinical Comparison of Cellulose and Expanded Polytetrafluoroethylene Membranes in the Treatment of Class II Furcations in Mandibular Molars With 6‐Month Re‐entry
Authors: dos Anjos Beatriz , Novaes Arthur B. , Meffert Roland , Barboza Eliane Porto
Published: March 2012

The present study compared two barrier membranes, ePTFE and cellulose, used to treat Class II furcations in mandibular molars. Fifteen patients with no history of systemic diseases and presenting matched pair defects were selected. The following soft tissue measurements were taken at baseline (after the hygienic phase), and 6 months after surgery: gingival recession, probing depth, clinical attachment level, and width of keratinized tissue. At the time of membrane placement, and 6 months later (re‐entry), the following hard tissue parameters were recorded: cemento‐enamel junction (CEJ) to alveolar crest, CEJ to base of osseous defect, alveolar crest to base of osseous defect, and horizontal defect depth. According to the surgical protocol, the ePTFE membranes were completely covered by the flaps (subgingival placement), whereas the cellulose membranes extended 1 mm coronal to the gingival margin (supragingival placement). Healing was uneventful in all cases and membranes remained in place for 4 weeks. Data were analyzed using the Wilcoxon signed‐rank test at the 5% level of significance. No statistically significant differences were found between the ePTFE and cellulose membranes, respectively (in mm): probing depth reduction (2.87±1.0 versus 3.27±1.1), gain in attachment level (2.53±1.2 versus 2.8±1.3), defect fill (3.0±1.4 versus 4.0±2.3), horizontal furcation fill (2.87±1.1 versus 2.93±1.0), alveolar crest resorption (2.4±10 versus 2.73±1.2), and intrabony defect fill (0.6±1.2 versus 1.27±1.7). We conclude that both ePTFE and cellulose membranes are effective, not showing statistical differences in efficacy. A larger study may be necessary to show differences in efficacy and adverse effects. J Periodontol 1998;69:454–459.
A Histological Study on Tissue Responses to Titanium Implantation in Rat Maxilla: The Process of Epithelial Regeneration and Bone Reaction
Authors: Fujii Noritaka , Kusakari Haruka , Maeda Takeyasu
Published: March 2012

The present study aimed to establish a titanium implantation model using rat maxillae as well as demonstrate the chronological tissue responses to implantation. Pure titanium implants were inserted, in the upper first molar extraction sites of Wistar rats 1 month after tooth extraction. The animals were sacrificed at 1 to 30 days postimplantation, and prepared tissue specimens were processed for light microscopy. The removal of implants from tissue blocks was done using 2 methods: mechanical removal or a cryofracture technique. In the early stages, peri‐implant tissues showed severe damage to the oral epithelium and collagen bundles with significant inflammatory cell infiltration. The peri‐implant epithelium grew apically along the implant by 10 days postimplantation, and regenerated to show a similar feature of junctional epithelium seen in normal rats at 15 days postimplantation, at which time no signs of inflammation were observed. The regenerated collagen bundles in the connective tissue were arranged circumferentially to the implants in the horizontal sections. New bone formation first appeared around the implants at 5 days postimplantation, covering the entire perimeter of implants by 30 days postimplantation. Scanning electron microscopic observations of the surface texture of the removed implants suggest the probability of an adhesive mechanism between the implants and the peri‐implant epithelium and/or the alveolar bone. These findings indicate that this experimental model is useful for detailed analysis of peri‐implant tissue because of its easy implantation procedure. J Periodontol 1998;69:485–495.
Association of Oral Spirochetes From Periodontally Healthy Sites With Development of Gingivitis
Authors: Riviere George R. , DeRouen Timothy A.
Published: March 2012

The purpose of this investigation was to determine whether the presence of selected disease‐associated bacteria in health‐associated plaque correlated with future gingivitis. Sites of periodontal health were identified in 65 adults. Six months later (recall 1) plaque was collected from sites that remained in periodontal health, and 5 species of specific bacteria and pathogen‐related oral spirochetes were detected using monoclonal antibodies in a microscopic assay. Members of the spirochete morphogroup were also identified by phase contrast microscopy. The relationship between site‐specific detection of bacteria at recall 1 and development of gingivitis at recall 2 or 3 was evaluated by means of logistic regression using generalized estimating equations, from which odds ratios (OR) were estimated. Significance was conservatively defined as OR > 2.0 and P < 0.05. We found that 488 of 1,424 healthy sites developed gingivitis over the 12‐month interval between recall 1 and 3. Only the spirochete morphogroup (OR = 2.04; P = 0.002) was significantly associated with the transition from health to gingivitis. The association of Treponema socranskii with future gingivitis was higher than expected (OR = 2.27), but the relationship was not statistically significant (P = 0.163). Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, and pathogen‐related oral spirochetes did not correlate well with gingivitis (OR < 2.0). Health‐associated plaque from 5 sites contained Treponema denticola, and all 5 sites progressed to gingivitis. An OR could not be calculated because T. denticola was not detected in health‐associated plaque from stable healthy sites. These findings indicated that the presence of T. denticola and unidentified spirochetes in health‐associated plaque was associated with increased susceptibility to gingival inflammation. Future studies assessing a larger panel of dental plaque microorganisms, with shorter intervals between baseline and follow‐up assessment, are necessary to more fully evaluate the association between detection of specific organisms at healthy sites and risk for gingivitis. J Periodontol 1998;69:496–501.
Three‐Dimensional Alveolar Bone Morphology Analysis Using Computed Tomography
Authors: Naito Toru , Hosokawa Ryuji , Yokota Makoto
Published: March 2012

The purpose of the present study was to determine whether the use of 3‐dimensional computed tomography (3DCT) is an effective method of imaging bone defect morphology caused by periodontal disease. A total of 186 sites from 9 patients were examined. Periodontal parameters were recorded after initial therapy. For the evaluation of bone resorption and root morphology, computed tomography (CT) scanning was performed and then CT images were reconstructed for 3‐dimensional evaluation. Immediately prior to the surgery, bone sounding measurements were done under local anesthesia. The denuded bone measurement during periodontal surgery represented the true bone level. To compare the bone level obtained from 3DCT images with the true bone level, the examiner, without being informed of the patient's condition, traced the cemento‐enamel junction (CEJ) and apical extent of the bone levels on the images of 3DCT, and measured the vertical distance between the CEJ and bone. The mean difference between 3DCT and the true bone level was 0.41±2.53 mm (mean±SD). The correlation between them showed a highly significant linear regression (R = 0.75). However, the mean difference between the bone sounding level and the true bone level was 0.22±1.49 mm (R = 0.91). Thus, bone sounding was slightly more accurate than 3DCT, but there was no significant difference between these two assessments (P >0.05). The results of present study indicate that 3DCT has the potential to allow precise assessment of bone defect caused by periodontal disease. J Periodontol 1998;69:584–589.
A Combined Approach for Treatment of Developmental Groove Associated Periodontal Defect. A Case Report
Authors: Andreana Sebastiano
Published: March 2012

Developmental grooves are not rare and often appear on maxillary lateral incisors. This may represent a challenge and sometimes tooth extraction is inevitable. This case report describes a combined technique of regenerative and antimicrobial/root conditioning used to treat a maxillary lateral incisor in a 32‐year‐old woman. Tooth #10 presented a periodontal probing depth, of 8 mm below the cingulum, associated with a developmental groove. The tooth was vital. After initial preparation, a palatal miniflap was raised, granulation tissue was eliminated by means of ultrasonic bactericidal curettage and radicoloplasty performed. The surface was then treated for 3 minutes with tetracycline‐HCl solution (100mg/ml), and the defect filled with sterile, medical grade, calcium sulfate. Clinical measurements were retaken at 6, 12, and 18 months. The results indicated a reduction of probing depth to 2 mm, reestablishment of the lamina dura, and radiographical evidence of bone growth. This combined treatment allowed the tooth to be saved, the palatal surgical approach did not alter the esthetics of the area, and its simplicity is recommended. J Periodontol 1998;69:601–607.
Clinical Comparison of Bioabsorbable Barriers With Non‐Resorbable Barriers in Guided Tissue Regeneration in the Treatment of Human Intrabony Defects
Authors: Teparat Thitiwan , Solt Charles W. , Claman Lewis J. , Beck F. Michael
Published: March 2012

The purpose of the study was to compare the effects of guided tissue regeneration (GTR) with expanded polytetrafluoroethylene (ePTFE) non‐resorbable barriers and polylactic acid bioabsorbable barriers in humans with intrabony defects due to periodontitis. Ten patients presented with 2 intrabony defects each. Mucoperiosteal flaps were performed. One of the defects was randomly assigned for placement of the ePTFE barrier over the roots and alveolar bone and the other defect with placement of the polylactic acid barrier. A minimum of 9 months after barrier placement, surgical reentry was performed. The data were evaluated by the Wilcoxon matched‐pairs signed‐ranks test and the Fisher exact test. Treatment with both types of barriers produced significant changes from baseline for all parameters, except in the ePTFE group for the amount of bony crest resorption (P = 0.055) and in the polylactic acid group for increased recession (P = 0.109). The results showed no significant differences between the barriers for any parameters: probing depth reduction (polylactic acid 2.60 ± 1.90, ePTFE 2.80 ± 1.40; P = 1.000); attachment gain (polylactic acid 1.40 ± 1.43, ePTFE 1.90 ± 1.29; P = 0.336); increased recession (polylactic acid 0.80 ± 1.40, ePTFE 1.10 ± 0.99; P = 0.531); amount of vertical bone fill (polylactic acid 1.60 ± 1.84, ePTFE 2.00 ± 2.49; P =0.984); bony crest resorption (polylactic acid −1.30 ± 1.06, ePTFE −1.30 ± 1.63; P = 1.000); depth of bony defect reduction (polylactic acid 2.90 ± 1.20, ePTFE 3.30 ± 1.70; P = 0.750); width of bony defect reduction (polylactic acid 2.20 ± 1.23, ePTFE 2.20 ± 1.23; P = 0.875); or volumetric changes (polylactic acid 33.50 ± 19.70 μl, ePTFE 34.00 ± 18.40 μl, P = 0.750). J Periodontol 1998;69:632–641.