bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunolocalization of c‐Myc and bcl‐2 Proto‐Oncogene Products in Gingival Hyperplasia Induced by Nifedipine and Phenytoin
Authors: Saito Keiichi , Mori Shiro , Tanda Naoko , Sakamoto Seizaburo
Published: February 2005

Background: Hyperplastic gingival tissues show the histopathological characteristics of thick parakeratinized squamous epithelia with acanthosis and rete pegs elongated into the lamina propria. However, the pathogenic factors that contribute to the epithelial morphogenesis of this disease are obscure and remain to be studied.

Methods: We immunohistochemically examined the expression of both c‐Myc and bcl‐2 oncoprotein, which can exert influence on the epithelial morphogenesis and homeostasis, in 12 hyperplastic gingival tissues induced by nifedipine and phenytoin as well as 5 control tissues using avidin‐biotin‐peroxidase complex methods.

Results: Four specimens out of 5 nifedipine‐induced and 5 out of 7 phenytoin‐induced hyperplastic gingival tissues revealed the expression of c‐Myc oncoprotein, whereas no significant immunostaining of c‐Myc oncoprotein was found in 5 control tissues. The c‐Myc oncoprotein‐positive cells were observed to be localized in the basal and suprabasal cell layers of the hyperplastic gingival epithelia. Although all of the 12 hyperplastic gingival epithelia showed the distribution of bcl‐2 oncoprotein in the basal and suprabasal layer cells, in 5 control epithelia the bcl‐2 oncoprotein expression was slight and confined to the basal layer cells.

Conclusions: The results of our present study indicate that the synergistic overexpression of c‐Myc and bcl‐2 oncoprotein may be related to the pathogenesis of gingival hyperplasia induced by nifedipine and phenytoin, especially to the morphogenesis of hyperplastic epithelia. J Periodontol 2000;71:44‐49.
Employing a Transgenic Animal Model to Obtain Cementoblasts In Vitro
Authors: D'Errico John A. , Berry Janice E. , Ouyang Hongjiao , Strayhorn Christopher L. , Windle Jolene J. , Somerman Martha J.
Published: February 2005

Background: Proper formation of cementum, a mineralized tissue lining the tooth root surface, is required for development of a functional periodontal ligament. Further, the presence of healthy cementum is considered to be an important criterion for predictable restoration of periodontal tissues lost as a consequence of disease. Despite the significance of cementum to general oral health, the mechanisms controlling development and regeneration of this tissue are not well understood and research has been hampered by the lack of adequate in vitro experimental models.

Methods: In an effort to establish cementoblast cell populations, without the trappings of a heterogeneous population containing periodontal ligament (PDL) cells, cells were obtained from the root surface of first mandibular molars of OC‐TAg transgenic mice. These mice contain the SV40 large T‐antigen (TAg) under control of the osteocalcin (OC) promoter. Therefore, only cells that express OC also express TAg and are immortalized in vitro. Based on results of prior in situ studies, OC is expressed by cementoblasts during root development, but not by cells within the PDL. Consequently, when populations are isolated from developing molars using collagenase/trypsin digestion, only cementoblasts, not PDL cells, are immortalized and thus, will survive in culture.

Results: The resulting immortalized cementoblast population (OC/CM) expressed bone sialoprotein (BSP), osteopontin (OPN), and OC, markers selective to cells lining the root surface. These cells also expressed type I and XII collagen and type I PTH/PTHrP receptor (PTH1R). In addition to expression of genes associated with cementoblasts, OC/CM cells promoted mineral nodule formation and exhibited a PTHrP mediated cAMP response.

Conclusions: This approach for establishing cementoblasts in vitro provides a model to study cementogenesis as required to enhance our knowledge of the mechanisms controlling development, maintenance, and regeneration of periodontal tissues. J Periodontol 2000;71:63‐72.
Effect of Cigarette Smoking on Periodontal Status of Healthy Young Adults
Authors: Machuca Guillermo , Rosales Isabel , Lacalle Juan R. , Machuca Carmen , Bullón Pedro
Published: February 2005

Background: It has been shown that tobacco is a significant risk factor for periodontal disease; however, there have been few studies on young populations where problems of general health can be discounted. The purpose of this study was to examine the influence of tobacco consumption on the periodontal condition of a young, healthy population.

Methods: The study population consisted of 304 young Caucasian males (average age 19.38 ± 0.72 years) entering the Armed Forces. All the subjects completed a self‐administered questionnaire on age, oral hygiene habits, previous dental examinations, and quantity and length of tobacco use. The periodontal examination consisted of the plaque index (PI); periodontal bleeding index (PBl); probing depth (PD); and clinical attachment level (CAL). One‐ and 2‐way ANOVA was used to compare data recorded between smokers and nonsmokers.

Results: Forty‐six percent of subjects reported that they brushed their teeth at least once a day, but only 13% visited a dentist at least once a year. Over half (53%) were habitual smokers, 43% smoking between 5 and 20 cigarettes per day; 39% of the smokers had been smoking for less than 5 years. Mean Pl was 31.24 ± 14.88 (27.19 ± 15.93 for smokers and 35.78 ± 12.17 for non‐smokers), with significant differences between non‐smokers and those who smoked 5 to 20 cigarettes per day (26.85 ± 16.11, P <0.0001). Mean PBl was 42.29 ± 8.43 (non‐smokers 44.67 ± 6.53 and smokers 40.17 ± 9.46). Significant differences were found between the PBl of the non‐smokers and of those who smoked 5 to 20 cigarettes per day (39.90 ± 9.64, P <0.0001). There were also differences in the PBl between those who brushed their teeth once (40.53 ± 9.61) and twice (44.86 ± 5.9) a day (P <0.0001). Mean PD was 1.62 ± 0.43 mm (non‐smokers 1.56 ± 0.36 and smokers 1.68 ± 0.49). Deeper probing depths were recorded among smokers than among non‐smokers, with statistically significant differences (P <0.049); statistically significant differences were also found between those who attended (1.49 ± 0.50) and those who did not attend (1.65 ± 0.42) regular dental check‐ups (P <0.031). Mean CAL 1.75 ± 0.41 (non‐smokers 1.64 ± 0.32 and smokers 1.82 ± 0.44).

Conclusions: It may be concluded that, even at such an early age, tobacco consumption affects the periodontal health. It is necessary to inform young smokers of the risk of tobacco use regarding periodontal health. J Periodontol 2000;71:73‐78.
Periodontal Probing: Probe Tip Diameter
Authors: Garnick Jerry J. , Silverstein Lee
Published: February 2005

Background: Periodontal probing is one of the most common methods used in diagnosing periodontal disease. The purpose of this study was to determine the importance of the diameter of periodontal probing tips in diagnosing and evaluating periodontal disease.

Methods: The literature discussing periodontal probe diameters in human, dog, and monkey studies was reviewed and compared. Tip diameters varied from 0.4 to over 1.0 mm in these studies. Probe advancement between the gingiva and the tooth is determined by the pressure exerted on the gingival tissues and resistance from the healthy or inflamed tissue. The pressure is directly proportionate to the force on the probe and inversely proportionate to the probe tip diameter. The larger probing diameters reduced probe advancement into inflamed connective tissue. This effect of change in probe diameter reduced the pressure in a greater manner than an increase of similar change in probe force.

Results: In the studies reviewed, the pressure used to place the probe tip at the base of the periodontal sulcus/pocket was approximately 50 N/cm2 and at the base of the junctional epithelium, 200 N/cm2. A tip diameter of 0.6 mm was needed to reach the base of the pocket. Clinical inflammation did not necessarily reflect the severity of histological inflammation, and the recordings may not illustrate probing depth. Furthermore, probing depth did not identify anatomical locations at the base of the pocket.

Conclusions: Probe tips need to have a diameter of 0.6 mm and a 0.20 gram force (50 N/cm2) to obtain a pressure which demonstrates approximate probing depth. This pressure was needed to measure the reduction of clinical probing depth, which included formation of a long junctional epithelium as a result of therapy. In addition, different forces or diameter tips are needed to measure healthy or inflamed histological periodontal probing depths. J Periodontol 2000;71:96‐103.
Periodontal Disease Progression
Authors: Reddy Michael S. , Geurs Nico C. , Jeffcoat Robert L. , Proskin Howard , Jeffcoat Marjorie K.
Published: February 2005

Background: The objective of this investigation is to use noninvasive, state‐of‐the‐art, diagnostic techniques to measure periodontal disease progression and model periodontal disease activity over time. In this investigation, digital subtraction radiography and an electronic controlled force periodontal probe capable of attachment level measurement were used to measure bone loss and attachment loss, respectively. The use of these nearly continuous measures of attachment and bone loss allowed detection of small amounts of disease activity and provided data to be used in modeling of the disease process over time.

Methods: Forty‐four patients were studied for 18 months. Examinations used clinical attachment level measures at 1‐month intervals and quantitative radiology at 6‐month intervals. The sites were analyzed by regression for statistically significant changes. These data were used to determine sites of periodontal disease activity for testing various models of periodontal disease progression.

Results: Overall 22.8% of sites lost attachment, 5.4% gained, and 71.7% demonstrated no statistically significant change. The mean time to lose 1 mm of attachment was 8.4 ± 0.6 months. In the first model tested a step‐wise discriminant analysis was used to determine whether or not baseline measurements of plaque (PI), gingival inflammation (GI), attachment loss, and probing depth (PD) could be used to derive a satisfactory model for disease progression. Although the overall model was statistically significant with PI, PD, and GI contributing to the model (Wilks' lambda = 0.859, F = 5.71, P <0.0012), its predictive power was relatively weak. A considerably stronger significant model resulted when the rate of attachment loss over the first 6 months, baseline PI, and baseline GI were included (Wilks' lambda = 0.712, F = 14.17, P <0.00001). A significant model also resulted when bone loss during the first 6 months and baseline probing depth were included (Wilks' lambda = 0.438, F = 61.48, P <0.00001). When the last model was applied to each site, the sensitivity in predicting disease progression was 80.0% and the specificity in ruling out progressive disease was 93.9%.

Conclusions: This study indicates that clinically significant progression of attachment loss in posterior tooth sites occurs as a frequent event in adult periodontitis. The modeling data also suggest that short‐term (6 month) measures of periodontal disease progression greatly improve the ability to model attachment loss over a longer period in untreated periodontitis patients. J Periodontol 2000;71:1583‐1590.
Growth Factors Regulate Expression of Mineral Associated Genes in Cementoblasts
Authors: Saygin N. Esra , Tokiyasu Yoshihiko , Giannobile William V. , Somerman Martha J.
Published: February 2005

Background: Knowledge of the responsiveness of cells within the periodontal region to specific bioactive agents is important for improving regenerative therapies. The aim of this study was to determine the effect of specific growth factors, insulin‐like growth factor‐I (IGF‐I), platelet‐derived growth factor‐BB (PDGFBB), and transforming growth factor‐β (TGF‐β) on cementoblasts in vitro and ex vivo.

Methods: Osteocalcin (OC) promoter driven SV40 transgenic mice were used to obtain immortalized cementoblasts. Growth factor effects on DNA synthesis were assayed by [3H]‐thymidine incorporation. Northern analysis was used to determine the effects of growth factors on gene expression profile. Effects of growth factors on cementoblast induced biomineralization were determined in vitro (von Kossa stain) and ex vivo (re‐implantation of cells in immunodeficient (SCID) mice).

Results: All growth factors stimulated DNA synthesis compared to control. Twenty‐four hour exposure of cells to PDGFBB or TGF‐β resulted in a decrease in bone sialoprotein (BSP) and osteocalcin (OCN) mRNAs while PDGF‐BB also increased osteopontin (OPN) mRNA. Cells exposed to IGF‐I for 24 hours exhibited decreased transcripts for OCN and OPN with an upregulation of BSP mRNA noted at 72 hours. In vitro mineralization was inhibited by continuous application of PDGF‐BB or TGF‐β, while cells exposed to these factors prior to implantation into SCID mice still promoted biomineralization.

Conclusions: These data indicate IGF‐I, PDGF‐BB, and TGF‐β influence mitogenesis, phenotypic gene expression profile, and biomineralization potential of cementoblasts suggesting that such factors alone or in combination with other agents may provide trigger factors required for regenerating periodontal tissues. J Periodontol 2000;71:1591‐1600.
Repair of an Intrabony Defect From an Adenomatoid Odontogenic Tumor
Authors: Blumenthal Neil M. , Mostofi Reza
Published: February 2005

This case report describes the occurrence and treatment of an adenomatoid odontogenic tumor (AOT) presenting as a periodontal intrabony defect on a upper lateral incisor. Following incision and flap reflection, a solid, rubbery specimen was enucleated in one piece leaving a wide moat‐like intrabony defect. A bioabsorbable membrane of glycolide and lactide copolymer was sutured over the defect to maximize regeneration and the flaps then sutured over the membrane. Microscopic analysis of the biopsied specimen revealed dental hard tissue interspersed in a field of odontogenic epithelium in a glandular configuration, consistent with a diagnosis of AOT. AOT is a rare odontogenic tumor usually associated with unerupted teeth or dentigerous cysts, not periodontal defects. Clinical evaluation 6 months postoperatively revealed restoration of clinical attachment and periodontal health. J Periodontol 2000;71:1637‐1640.
Multi‐Center Clinical Comparison of Combination Anorganic Bovine‐Derived Hydroxyapatite Matrix (ABM)/Cell Binding Peptide (P‐15) and ABM in Human Periodontal Osseous Defects. 6‐Month Results
Authors: Yukna Raymond A. , Krauser Jack T. , Callan Donald P. , Evans Gerald H. , Cruz Renee , Martin Millicent
Published: February 2005

Background: Intraosseous periodontal defects present a particular treatment problem. New bone replacement grafts offer promise for improved results.

Methods: The role of a synthetic cell‐binding peptide (P‐15), combined with an anorganic bovine‐derived hydroxyapatite bone matrix (ABM), was compared to ABM alone in human periodontal osseous defects in a controlled, monitored, multi‐center trial. Following appropriate initial preparation procedures, flap surgery with defect and root debridement was performed. Two osseous defects per patient were treated randomly with each procedure after surgical preparation. Appropriate periodontal maintenance schedules were followed, and at 6 to 7 months, re‐entry flap surgery was performed for documentation and finalization of treatment.

Results: T test and Mann‐Whitney U analyses of patient mean values from 33 patients revealed that the combination ABM/P‐15 grafts demonstrated significantly better mean defect fill of 2.9 ± 1.2 mm (72.9%) versus a mean defect fill of 2.2 ± 1.4 mm (50.67%) for defects treated with ABM (P <0.05). Other hard tissue findings showed similar clinically superior results with the use of ABM/P‐15. Relative defect fill results showed 81% positive (50% to 100% defect fill) responses with ABM/P‐15 and 67% positive responses with ABM. There were 3.5 times as many optimal results (≥90% defect fill) with ABM/P‐15 and twice as many failures (minimal response) with ABM. Soft tissue findings showed no significant differences between treatments.

Conclusions: These results suggest that the use of the P‐15 synthetic cell‐binding peptide combined with ABM yields better clinical results than the ABM alone in intrabony periodontal defects. J Periodontol 2000;71:1671‐1679.
Treatment of Human Mucogingival Defects Utilizing a Bioabsorbable Membrane With and Without a Demineralized Freeze‐Dried Bone Allograft
Authors: Duval Benjamin T. , Maynard J. Gary , Gunsolley John C. , Waldrop Thomas C.
Published: February 2005

Background: The use of guided tissue regeneration (GTR) has become an effective procedure for the treatment of gingival recession. No reports exist on the use of a bioabsorbable membrane in combination with a demineralized freeze‐dried bone allograft (DFDBA) for the treatment of these defects.

Methods: Fourteen (14) patients with 17 recession defects were included in this clinical study. Each patient had at least 1 tooth with 3 mm or greater marginal tissue recession on the facial surface as measured from the cemento‐enamel junction (CEJ). Each patient was treated by GTR using a bioabsorbable membrane. When the first patient presented for inclusion in the study, a coin was flipped to determine if the tooth being treated would be a test tooth (DFDBA) or a control tooth (no DFDBA). Each subsequent patient was alternated between test and control. Immediately prior to the surgical procedure, measurements were made which included recession depth, recession width at the widest point, probing depth, amount of keratinized tissue, and marginal tissue thickness. Local anesthesia was administered, and a measurement from the CEJ to the bone crest was made by sounding through the attachment.

Results: The mean initial recession for all defects was 3.35 mm (SD ± 0.49) and at 6 months postsurgery, mean recession was 0.47 mm (SD ± 0.62). This correlated to 86% root coverage for both treatments. For all defects treated, there was a statistically significant increase in keratinized tissue (mean 0.88 mm) and tissue thickness (mean 0.47 mm) and a significant decrease in probing bone level (mean 0.76 mm). No statistically significant differences were observed between groups for any parameter.

Conclusions: Although only 14 subjects with 17 defects were included in this study, the results suggest that the treatment of human gingival recession with a bioabsorbable membrane with or without the use of DFDBA results in significant root coverage, and slight, but significant improvements in keratinized tissue, tissue thickness, and bone level. The greatest limitation of the study was its lack of statistical power. Twenty‐two (22) subjects would have been required for the results of the study to show equivalence between groups. J Periodontol 2000;71:1687‐1692.
Width of Keratinized Tissue After Gingivoplasty of Healed Subepithelial Connective Tissue Grafts
Authors: Maurer Susanne , Hayes Catherine , Leone Cataldo
Published: February 2005

Background: The subepithelial connective tissue graft has markedly broadened clinicians' abilities to treat gingival recession. Frequently, however, bulky soft tissue contours are sequelae of this procedure, and post‐healing gingivoplasty is often performed to improve esthetics of the grafted site. As a secondary benefit, it is believed that the zone of keratinized tissue is additionally increased after gingivoplasty.

Methods: To further investigate this clinical impression, 16 bilateral pairs of sites with recession in 6 consecutive patients (mean age = 38 ± 9 years) were studied. At the time of initial grafting, one site in each pair was randomly assigned to receive either gingivoplasty 2 months later (GP+) or no further treatment (GP‐). Clinical measurement of recession and keratinized tissue width was standardized using customized acrylic stents and Schiller iodine solution, which stains epithelia; values were recorded at baseline (day of graft) and at 2, 3, and 5 months after grafting. Mean clinical gingival widths over time between GP+ and GP‐ sites, as well as within GP+ sites, were analyzed by t test.

Results: At 5 months, both the GP+ and GP‐ sites demonstrated a mean root coverage of 87.4% and increased keratinized tissue width (1.2 mm) when compared to their respective baseline measures. No differences in recession depth and width of keratinized tissue were seen at 5 months between the GP+ and GP− groups. In addition, no differences in recession or gingival width were found between 2‐ and 5‐month observations for either the GP+ or GP‐ groups.

Conclusions: These data suggest that the observed clinical improvements are the outcome of the initial graft surgery and that the gingivoplasty procedure does not result in additional (or “rebound”) increases in keratinized tissue width. J Periodontol 2000;71:1729‐1736.
Ameliorated Effect of L‐Arginine Supplementation on Gingival Morphology in Cyclosporin‐Treated Rats
Authors: Fu Earl , Tz‐Chong Chou , Liu Demeral , Chiu Shian‐Chung
Published: February 2005

Background: The role of nitric oxide (NO) in the pathogenesis of cyclosporin (CsA)‐induced gingival overgrowth is unknown. The purpose of the present study was to evaluate the effect of NO substrate (L‐arginine) and blockade (N‐nitro‐L‐arginine methylester‐hydrochloride, L‐NAME) on the gingival morphology in CsA‐fed rats.

Methods: Sixty CsA‐fed (10mg/kg/day) male Sprague‐Dawley rats were assigned to 3 groups. Animals in 2 experimental groups received L‐arginine (1% weight/weight) in rat chowder or L‐NAME (50 mg/l) in drinking water, respectively, for 4 weeks. Rats in the control group were fed a normal diet and water. At week 0, 2, and 4, dental stone models were made from the mandibular anterior region and the gingival dimensions (width, depth, and height) were measured. The tail cuff blood pressure and the plasma nitrate level were also measured at week 4 to monitor the effects of L‐arginine and L‐NAME treatment.

Results: No significant difference in the gingival dimensions was noticed at week 0; however, significant differences were observed at weeks 2 and 4, except the buccolingual depth at week 2. While the magnitude of gingival dimensions was large, moderate, and small in control, L‐NAME, and L‐arginine groups, respectively, we found significantly reduced gingival dimensions in both L‐arginine supplement and L‐NAME groups. Nevertheless, the reduced gingival overgrowth in the L‐NAME treatment group was far less than that in the exogenous NO treatment group. Plasma NO2‐/ NO3‐ concentrations were also significantly different; i.e., from the highest to the lowest levels were the L‐arginine, CsA control, and L‐NAME group, respectively. A significantly increased mean and diastolic blood pressure was found in the L‐NAME group compared to the L‐arginine group.

Conclusions: Gingival morphology in CsA‐fed rats was evaluated after NO substrate (L‐arginine) and blockade (L‐NAME) treatment for 4 weeks. Significantly decreased dimensions were noted in the L‐arginine group compared to the CsA group at weeks 2 and 4. Although an inhibitory effect on the gingival morphology was also observed in the L‐NAME group, another unknown mechanism might be involved. Within the limitations of the study, we suggest that NO may have an important role in the mechanism of CsA‐induced gingival overgrowth. J Periodontol 2000;71:1737‐1742.
Guided Bone Regeneration Around Endosseous Implants With Anorganic Bovine Bone Mineral. A Randomized Controlled Trial Comparing Bioabsorbable Versus Non‐Resorbable Barriers
Authors: Carpio Lillian , Loza Juan , Lynch Samuel , Genco Robert
Published: February 2005

Background: Guided bone regeneration (GBR) is a viable treatment for osseous defects surrounding dental implants. Controversy exists regarding the choice of barrier membrane used and the method of membrane fixation to achieve GBR.

Methods: This study compared the efficacy of a porcine‐derived bioabsorbable collagen membrane and an expanded polytetrafluoroethylene (ePTFE) membrane (non‐resorbable) for GBR using a bovine bone xenograft/autograft bone composite in defects surrounding dental implants. The study also examined the effect of primary barrier fixation on GBR. Defect size was recorded at Stage 1 and 2 surgeries (performed 6 months apart). Forty‐eight subjects (41% males, 59% females) requiring GBR were treated with either collagen (23) or ePTFE (25) barriers, respectively. Implants were titanium self‐tapping screw‐type. In 34 GBR sites, barrier fixation was achieved with polylactic acid resorbable pins. The remaining barriers were secured with the implant cover screw and/or embedded beneath the flaps.

Results: At 6 months, a decrease in defect width (collagen barrier 1.95 ± 0.60 mm, ePTFE barrier 2.65 ± 0.56 mm), length (collagen barrier 2.65 ± 0.61 mm, ePTFE barrier 2.26 ± 0.66 mm), and circumference (degrees) (collagen barrier 57.7 ± 18.7, ePTFE barrier 80.2 ± 19.9) was observed for both membranes. A significant number (X 2, P = 0.041) of postoperative complications occurred when barrier fixation was lacking at initial surgery. Furthermore, a significant difference (P <0.05) in the success of GBR with respect to defect size was observed when barrier fixation was taken into account.

Conclusions: In conclusion, both collagen and ePTFE barriers proved suitable for achieving GBR of osseous defects surrounding dental implants. The results of this study stress the importance of barrier fixation at the time of initial surgery. J Periodontol 2000;71:1743‐1749.
Comparison of 5 Protocols Based on Their Abilities to Use Data Extracted From Digitized Clinical Radiographs to Discriminate Between Patients With Gingivitis and Periodontitis
Authors: Shrout Michael K. , Hildebolt Charles F. , Potter Brad J. , Comer Robert W.
Published: February 2005

Background: This study was undertaken to compare 5 digital analytic protocols for their abilities to extract data from digital clinical radiographs and discriminate between patients with gingivitis and periodontitis.

Methods: Five digital‐image analysis protocols were compared for their abilities to discriminate between two groups of 24 patients each. One group was diagnosed with healthy gingiva (or gingivitis) and the second with periodontitis. These groups were previously evaluated in published studies that used fractal and morphologic analyses. Pre‐existing clinical radiographs for each patient were digitized and regions of interest (ROIs) were placed on interdental bone in mandibular posterior quadrants. The 5 protocols used were: 1) MGB: a median filtration to remove high‐frequency noise, a Gaussian filtration to remove low‐frequency noise, binarization of the resulting image, and quantification of the black pixels; 2) MGBS: the same protocol as MGB except for a skeletonization of the binary image and a quantification of the skeleton's pixels; 3) GBS: Gaussian filtration, binarization (thresholding on the mean pixel value) of the resulting image, skeletonization, and quantification of the pixels of the skeleton; 4) NS: normalization, skeletonization, and quantification of the skeleton's pixels; and 5) S: a variation of NS, except normalization was not used. The resulting values for the 2 patient groups were compared with Mann‐Whitney U tests and effect likelihood‐ratio test.

Results: For digitized radiographs, the mean gray‐scale value (± standard deviation) for gingivitis patients was 183.22 ± 18.53 and for periodontitis patients 181.26 ± 17.20. Mann‐Whitney U tests resulted in the following P values for these protocols: MGBS <0.01; S <0.01; GBS <0.01; NS <0.01; and MGB <0.83. Effect likelihood‐ratio tests indicated that only MGBS and S significantly contributed to models containing the other factors.

Conclusions: Small variations to protocols affected the strength of the discrimination between the gingivitis and periodontitis groups. While there is potential for morphologic analysis to be used to discriminate between patients with gingivitis and periodontitis, a robust technique was not identified. J Periodontol 2000;71:1750‐1755.
Treatment of Periodontal Destruction Associated With a Cemental Tear Using Minimally Invasive Surgery
Authors: Harrel Stephen K. , Wright John M.
Published: February 2005

Background: A patient presented with moderate probing depth, pain on occlusal contact, and a fistula on a mandibular bicuspid. The probing depth increased 2 mm over a 3‐month period despite relief of the occlusal trauma and resolution of the fistula. A radiograph showed an apparent separation of the cementum in the area of the pocket.

Methods: The lesion was treated using a minimally invasive surgical approach to place a bone graft.

Results: The probing depth was reduced to 2 mm with less than 1 mm of increased recession. A histologic examination of the damaged calcified tissue confirmed that it was cementum.

Conclusions: The increasing probing depth associated with a cemental tear seems to indicate that this phenomenon contributed to loss of attachment and bone. Removal of the detached cementum in combination with bone grafting using a minimally invasive surgical approach appears to have successfully corrected the periodontal destruction. J Periodontol 2000;7l:1761‐1766.
Angina Bullosa Hemorrhagica: An Unusual Problem Following Periodontal Therapy
Authors: Curran Alice E. , Rives Robert W.
Published: February 2005

Angina bullosa hemorrhagica (ABH) describes benign subepithelial oral blood blisters not attributable to a systemic disorder. Little is known about the pathogenesis of ABH, although most cases have been associated with mild trauma prior to appearance of the lesion. This report discusses the clinical and histopathologic features of ABH which appeared after routine scaling and root planing. J Periodontol 2000;71:1770‐1773.
Enamel Matrix Derivative in the Treatment of Human Intrabony Osseous Defects
Authors: Okuda Kazuhiro , Momose Manabu , Miyazaki Akira , Murata Masashi , Yokoyama Shigeru , Yonezawa Yukari , Wolff Larry F. , Yoshie Hiromasa
Published: February 2005

Background: There is limited information available from clinical trials regarding the performance of enamel matrix derivative (EMD) in the treatment of periodontal intrabony defects. This randomized, double‐blind, placebo‐controlled, split‐mouth study was designed to compare the clinical and radiographical effects of EMD treatment to that of placebo‐controlled treatment for intrabony defects.

Methods: Sixteen patients were included, each of whom had 1 or 2 pairs of intrabony defects located contralaterally in the same arch. Thirty‐six intrabony defects were randomly assigned treatment with flap surgery plus EMD or flap surgery plus placebo. At baseline and at the 12‐month follow‐up evaluation visit, clinical and radiographic measurements were determined. Data were statistically analyzed using the Wilcoxon‐signed rank test (α = 0.05).

Results: At the 12‐month visit, bleeding on probing for the EMD group was 0.11 ± 0.32 compared to the placebo group, 0.61 ± 0.50 (P <0.05). Probing depth reduction was greater in the EMD group (3.00 ± 0.97 mm) compared to the placebo group (2.22 ± 0.81 mm) (P <0.05). Mean values for clinical attachment gain in the EMD and the placebo groups were 1.72 ± 1.07 mm and 0.83 ± 0.86 mm, respectively (P <0.05). Vertical relative attachment gain was 38.5 ± 22.6% in the EMD group and 21.4 ± 25.2% in the placebo group (P <0.05). Radiographic bone density gain was greater in the EMD (20.2 ± 16.6%) compared to the placebo group (−3.94 ± 23.3%) (P <0.01).

Conclusions: Treatment with flap surgery and EMD, compared to flap surgery with placebo, produced a significantly more favorable clinical improvement in intrabony periodontal defects. J Periodontol 2000;71:1821‐1828.
Enamel Factors Regulate Expression of Genes Associated With Cementoblasts
Authors: Tokiyasu Y. , Takata T. , Saygin E. , Somerman M.
Published: February 2005

Background: In order to design predictable periodontal regenerative therapies, it is important to understand the responsiveness of cells within the local environment to factors considered attractive candidates. The aim of this study was to determine the effect of an enamel matrix derivative (EMD) on cementoblast behavior in vitro and in vivo.

Methods: Osteocalcin (OC) promoter SV40 transgenic mice were used to obtain cementoblasts. For comparison, preosteoblasts from these mice, as well as another murine preosteoblast cell line, MC3T3‐E1 cells, were used. Cells exposed to EMD were evaluated for changes in: 1) proliferation over an 8‐day period by cell counting; 2) gene expression using Northern blot analysis; and 3) biomineralization by von Kossa stain, in vitro and by preparing histological samples from implants retrieved from immunodeficient (SCID) mice, where cementoblasts were treated with EMD prior to implantation.

Results: EMD promoted proliferation of all cell types. EMD down‐regulated osteocalcin transcripts in cementoblasts and MC3T3‐E1 cells and up‐regulated osteopontin gene expression markedly in MC3T3‐E1 cells and slightly in cementoblasts at day 8. In vitro, EMD decreased cementoblast‐mediated biomineralization. In contrast, mineralization was noted in implants retrieved from SCID mice, where cells were pretreated with EMD.

Conclusion: These results indicate that EMD can influence activities of cementoblasts and osteoblasts, and thus may be able to regulate cell activities at a periodontal regenerative site. J Periodontol 2000;71:1829‐1839.
Treatment of Intraosseous Defects with Bioabsorbable Barriers Alone or in Combination With Decalcified Freeze‐Dried Bone Allograft: A Randomized Clinical Trial
Authors: Trejo P.M. , Weltman R. , Caffesse R.
Published: February 2005

Background: This study clinically compares the outcomes obtained from the use of a bioabsorbable barrier device in combination with demineralized freeze‐dried bone allograft (DFDBA) to the results obtained from the barrier device used alone in the treatment of human intraosseous defects.

Methods: The study consisted of 30 patients with one intraosseous periodontal defect each. The trial included defects with loss of attachment of ≥6 mm, with a radiographically detectable defect of at least mm and with at least 2 remaining osseous walls. After the hygienic phase, at baseline, probing depth (PD), clinical attachment level (CAL), and recession (REC) were measured. During open flap debridement, the defects were randomly assigned to receive either a polylactic acid (PLA) barrier in combination with DFDBA (test) or a PLA barrier alone (control). Additionally, baseline osseous intrasurgical measurements of the periodontal defect were obtained to evaluate the amount of bone regeneration. PD, CAL, and REC were remeasured at 6 and 12 months postsurgery and osseous measurements repeated at 12 months during a re‐entry procedure.

Results: Two‐sample t‐test comparisons of mean PD, CAL, and REC measurements (mm) between test (PLA+DFDBA) and control (PLA alone) groups at baseline, PLA+DFDBA: PD = 7.3, CAL = 8.1, REC = ‐0.7; PLA‐alone: PD = 7.9, CAL = 8.4, REC = ‐0.5, were not statistically different (P >0.05). The following mean changes (Δ) at 6 months for the test and the control groups were: decreased PD = 3.6 and 4.0 mm; gain CAL = 2.7 and 3.1 mm; and increased REC = ‐0.8 and ‐0.8 mm, respectively. At 12 months the changes for the test and control groups were: decreased PD = 3.3 and 4.1 mm; gain CAL = 2.3 and 3.2 mm; and increased REC = ‐0.8 and ‐1.0 mm, respectively. Two‐sample t‐test comparisons between PD, CAL, and REC changes yielded no significant differences between treatments (P >0.05), except for the change in CAL at 12 months in favor of the control group, P = 0.008. Comparisons of osseous measurements resulted in no significant differences between groups at baseline and at 12 months (P >0.05). The intrabony defect filled on the average 3.72 mm for the test and 4.85 mm for the control group. The experimental defects showed a 4.73 mm defect depth reduction, while the control defects reduced 5.35 mm. Re‐entry measurements of osseous crest resorption were 1.1 mm for the test and 0.61 mm for the control.

Conclusions: In the intraosseous defects treated in this study, the addition of DFDBA to the GTR procedure did not significantly enhance the clinical results obtained with the GTR procedure alone. J Periodontol 2000;71:1852‐1861.
The Clinical and Microbiological Effects of Systemic Ornidazole in Sites With and Without Subgingival Debridement in Early‐Onset Periodontitis Patients
Authors: Kamma Joanna J. , Nakou Mela , Mitsis Fotis J.
Published: February 2005

Background: The purpose of this study was to evaluate the clinical and microbiological effects of systemic ornidazole (ORN) in sites with or without subgingival debridement in early‐onset periodontitis (EOP) patients.

Methods: Two pooled bacterial samples consisting of 4 sites each (scaled and non‐scaled sites) were obtained from 30 individuals exhibiting EOP. All patients received oral hygiene instruction (OHI), supragingival scaling and ORN. Subgingival scaling and root planing (SRP) was carried out only in scaled sites. Bacterial samples were taken at baseline (BL) and 1 week and 2, 6, and 12 months after systemic ornidazole administration (500 mg/bid for 7 days). One more sample was taken at scaled sites, one week after SRP.

Results: One week following SRP (scaled sites) Gram‐negative facultative and anaerobic rods were significantly reduced while Gram‐positive facultative cocci were significantly increased. After ORN administration, P. gingivalis, P. denticola, P. intermedia, B. forsythus, C. rectus, and S. sputigena were no longer detectable in either scaled or non‐scaled sites. A statistically significant long‐term (2, 6, and 12 months) reduction of P. gingivalis, P. intermedia, P. loescheii, B. forsythus, and C. rectus and a pronounced increase of S. milleri, S. oralis, and S. sanguis counts in both scaled and non‐scaled sites were detected in comparison to baseline. A sustained reduction of bleeding tendency and of probing depth was also observed in both scaled and non‐scaled sites.

Conclusions: ORN combined with SRP effects beneficial shifts in the bacterial population associated with substantial clinical improvement, thereby indicating that ORN is effective adjunct in the treatment of EOP deep periodontal pockets where anaerobic bacteria are predominant. J Periodontol 2000;71:1862‐1873.
Emergency Tracheostomy Following Life‐Threatening Hemorrhage in the Floor of the Mouth During Immediate Implant Placement in the Mandibular Canine Region
Authors: Givol Navot , Chaushu Gavriel , Halamish‐Shani Tali , Taicher Shlomo
Published: February 2005

Background: The edentulous interforaminal mandibular area is frequently the preferred area for implant placement.

Methods: A case of emergency tracheostomy following life‐threatening hemorrhage in the floor of the mouth during immediate implant placement in the mandibular canine region is described. The probable cause was bleeding from the sublingual artery or a branch of that artery following implant perforation of the lingual cortex.

Results: Healing was uneventful and the patient was released from the hospital after 11 days. Three years later, CT showed a well‐osseointegrated implant with a severe buccolingual inclination.

Conclusions: It is stressed that short implants (14 mm or less) should be used in the mandibular canine region and that effective treatment of this complication is essential. J Periodontol 2000;71:1893‐1895.
Oral Lesions in Patients With Psoriasis: Clinical Presentation and Management
Authors: Brice Darla M. , Danesh‐Meyer Michael J.
Published: February 2005

Psoriasis is a chronic inflammatory skin disease that rarely involves the oral cavity. In this report we describe 2 cases, initially diagnosed with cutaneous psoriasis, that present with oral lesions on the attached gingiva. The clinical appearance and differential diagnosis are presented and discussed. Case 1 describes the non‐surgical management of intraoral psoriasiform lesions and the use of a free gingival graft to restore an area of gingival recession resulting from an oral lesion. The second case outlines the use of topical corticosteroid therapy as an adjunct to nonsurgical periodontal therapy. Although patients with cutaneous psoriasis rarely present with oral involvement, the clinician should be aware that oral lesions may occur. Accurate diagnosis is dependent on a thorough clinical examination, a biopsy of the oral lesions, and a history of cutaneous psoriasis. J Periodontol 2000;71:1896‐1903.
Conditions for Success in Guided Bone Regeneration: Retrospective Study on 376 Implant Sites
Authors: Mattout Paul , Mattout Catherine
Published: February 2005

Background: Used alone or in association with bone, guided bone regeneration is a clinically accepted method to increase the volume of bone during implant placement. Concerns about appropriate surgical techniques and the predictability of the results questions still exist. The aim of this study was to assess the conditions for success.

Methods: Three‐hundred‐seventy‐six implants were placed in association with 214 non‐resorbable membranes. In 109 implants, the membrane was secured on a blood clot; for 213 implants, membrane was placed with autogenous bone; and for 54 implants it was placed with allogenic bone. The surgical procedure, the primary closure, the timing of re‐entry, and the density of regenerated tissue were studied.

Results: In 19 membranes, barrier exposure occurred before 3 months in these instances, the regenerated tissue was removed; another 7 membranes were exposed between 3 and 6 months. The 188 non‐exposed membranes were removed between 6 and 12 months. In cases of exposure before 3 months, the regenerated tissue was soft and then removed. After closure for 6 months or more, the renegerated tissue was dense and resistant to probe pressure. The best results were obtained when the membranes were placed with autogenous bone.

Conclusions: If all the clinical steps are appropriately followed, guided bone regeneration using an autogenous bone graft and implant placement is a predictable technique for increasing bone volume. J Periodontol 2000;71:1904‐1909.
Root Substance Removal With Er:YAG Laser Radiation at Different Parameters Using a New Delivery System
Authors: Folwaczny Matthias , Mehl Albert , Haffner Cornelius , Benz Christoph , Hickel Reinhard
Published: February 2005

Background: The recently introduced Er:YAG laser radiation appears to be a promising alternative in treating dental hard tissue due to its thermo‐mechanical ablation properties and the lack of thermal side effects. The present in vitro study attempted to evaluate the use of Er:YAG laser radiation in combination with a specially developed delivery system in removing calculus from root surfaces.

Methods: Fifty extracted anterior teeth, premolars and molars, were divided into 2 groups of 25 each with (group A) and without (group B) subgingival calculus. Source of radiation was an Er:YAG laser device with a wavelength of 2.94 µm, in the infrared optical spectrum, a pulse duration of 250 ns, and a pulse repetition rate of 15 pps. In each group, 6 teeth were irradiated with 300 laser pulses either at 60 mJ, 80 mJ, 100 mJ, or 150 mJ. The samples were continually moved linearily using a computer numeric controlled device. The volumetric evaluation of root substance removal was performed with a 3‐dimensional laser scanning system (100,000 surface points per sample, accuracy: 5 µm) and special image analyzing software. A scanning electron microscopic (SEM) observation was performed to assess the laser induced ultrastructural changes on the root surfaces. Statistical analysis was carried out with ANOVA followed by the Scheffé test and with regression analysis according to Pearson‐Bravais at a level of significance of 5% (P <0.05).

Results: The linear measurement of substance removal on calculus samples (group A) revealed average depths between 174.38 (±16.13) µm and 501.85 (±111.01) µm. Defect depths on the teeth without calculus (group B) ranged from 37.78 (±14.03) µm to 484.44 (±80.63) µm. The SEM observation of laser‐treated root surfaces revealed no signs of thermal damage; e.g., melting, fusion, or cracking.

Conclusions: The results of the present study showed that a substance removal with Er:YAG laser radiation at lower energy densities is comparable, in effect, to that after conventional root surface instrumentation with curets. The results seem to indicate that calculus removal can be selectively done using lower radiation energies. Considering the favorable results of the SEM investigation, the use of the Er:YAG laser in periodontal therapy may be possible in the future. J Periodontol 2000;71:147‐155.
Interleukin‐1 Genetic Association With Periodontitis in Clinical Practice
Authors: McDevitt Michael J. , Wang Hwa‐Ying , Knobelman Carol , Newman Michael G. , di Giovine Francesco S. , Timms Janice , Duff Gordon W. , Kornman Kenneth S.
Published: February 2005

Background: Periodontitis is a bacterial disease modified by multiple risk factors. The pro‐inflammatory cytokine interleukin‐1 (IL‐1) is a key regulator of the host responses to microbial infection and a major modulator of extracellular matrix catabolism and bone resorption. It has been reported that variations in the IL‐1 gene cluster on chromosome 2 are associated with increased susceptibility to severe adult periodontitis.

Methods: The present study evaluated the association between a composite IL‐1 genotype, including allele 2 at each of two loci (IL‐1A +4845 plus IL‐1B +3954), and a broad spectrum of periodontally healthy to diseased patients in a population that is typically encountered in a dental practice setting. Ninety patients, non‐smokers or former smokers with less than 10 pack‐year (pk/yr) history, were recruited from a private dental practice. The major outcome variable was bone loss determined by computerized linear measurements of radiographs. Genotypes were analyzed from finger‐stick blood samples using previously reported methods.

Results: Multivariate logistic regression models demonstrated that patient age, former smoking history, and the IL‐1 genotype were significantly associated with severity of adult periodontitis. For nonsmokers or former light smokers (<5 pk/yr), IL‐1 genotype positives were at increased odds ratio of having moderate to severe periodontal disease of 3.75 (95% CI: 1.04‐13.50) to 5.27 (95% CI: 1.23‐22.70), depending on ethnicity, compared to IL‐1 genotype negatives. Former moderate smokers (>5 pk/yr and <10 pk/yr) who were IL‐1 genotype negative were at increased odds ratio of having moderate to severe periodontal disease of 7.43 (95% CI: 1.20‐46.20) compared to non‐smokers or former light smokers who were IL‐1 genotype negative. In addition, past smoking history was also a significant effect modifier as demonstrated by the statistically significant interaction between past smoking history status and IL‐1 genotype status.

Conclusions: This study demonstrates that the composite IL‐1 genotype is significantly associated with the severity of adult periodontitis. It also confirmed that both IL‐1 genotyping and smoking history provide objective risk factors for periodontal disease in a private practice environment. J Periodontol 2000;71:156‐163.