Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Periodontium

  • healthy periodontium

  • Selected Abstracts

    Growth Hormone Induces Bone Morphogenetic Proteins and Bone-Related Proteins in the Developing Rat Periodontium

    Huika Li
    Abstract The hypothesis that growth hormone (GH) up-regulates the expression of enzymes, matrix proteins, and differentiation markers involved in mineralization of tooth and bone matrices was tested by the treatment of Lewis dwarf rats with GH over 5 days. The molar teeth and associated alveolar bone were processed for immunohistochemical demonstration of bone morphogenetic proteins 2 and 4 (BMP-2 and -4), bone morphogenetic protein type IA receptor (BMPR-IA), bone alkaline phosphatase (ALP), osteocalcin (OC), osteopontin (OPN), bone sialoprotein (BSP), and E11 protein (E11). The cementoblasts, osteoblasts, and periodontal ligament (PDL) cells responded to GH by expressing BMP-2 and -4, BMPR-IA, ALP, OC, and OPN and increasing the numbers of these cells. No changes were found in patterns of expression of the late differentiation markers BSP and E11 in response to GH. Thus, GH evokes expression of bone markers of early differentiation in cementoblasts, PDL cells, and osteoblasts of the periodontium. We propose that the induction of BMP-2 and -4 and their receptor by GH compliments the role of GH-induced insulin-like growth factor 1 (IGF-1) in promoting bone and tooth root formation. [source]

    Dental injuries resulting from tracheal intubation , a retrospective study

    Jobst Vogel
    Thus, this retrospective study was conducted including the data of 115,151 patients. All patients involved had been exposed to general anesthesia between 1995 and 2005. The resulting tooth injuries were assessed according to the following parameters: age, kind of hospital conducting treatment, intubation difficulties, pre-existing tooth damage, type and localization of tooth, type of tooth damage, and the number of teeth injured. At least 170 teeth were injured in 130 patients, while patients 50 years of age and older were especially affected. In contrast to older patients where in the majority of cases the periodontium (lateral dislocation) was injured, in younger patients dental hard tissue (crown fracture) was more likely to be affected. It was calculated that patients from the cardiothoracic surgery clinic were showing the highest risk of tooth damage. In more than three-fourth of all cases the anterior teeth of the maxilla, especially the maxillary central incisors, were affected. Pre-existing dental pathology like caries, marginal periodontitis and tooth restorations were often distinguishable prior to operation. Mouthguards in connection with tracheal intubation are not generally recommended as preventive device, due to the already limited amount of space available. Instead, pre-existing risk factors should be thoroughly explored before the induction of intubation narcosis. [source]

    Effect of crown fracture on the surrounding periodontium

    Janaína Cristina Gomes
    To reach the long axis of the tooth, an impact device was applied to eight teeth of four adult dogs to produce trauma. Crown fractures involving the enamel and dentin, with or without pulpar exposure and without dislocation, mobility or gingival bleeding were analyzed within the post-trauma periods of 30 min, 1, 3, and 7 days. The force of impact that resulted in coronary fracture, although dissipated at the time of fracture, reverberated in the surrounding periodontium and may generate not only light histological alterations with a rapid re-establishment of the tissues, but also an intense inflammatory condition required as long as 7 days to clear up. The gravity of these inflammatory reactions unleashed in these teeth's periapical tissues depends on the absorption of impact by the periodontal structures and the individual susceptibility of each organism. [source]

    Clinical and histological alterations in the surrounding periodontium of dog's teeth submitted for an intrusive luxation

    Janaína Cristina Gomes
    An impact device was used on 12 teeth of six adult dogs with the purpose of making a dislocation on the long axis of these teeth. Of the teeth that suffer intrusion luxation, two did not receive treatment and ten were replaced by orthodontic extrusion with activated springs of 100 gf. The traction was initiated either immediately after the trauma or 7 days later. Observation time was 40 days. Endodontic therapy with calcium hydroxide was performed on the fourteenth day after the intrusive luxation. The intruded teeth that did not receive appropriate treatment had signs of extensive and progressive inflammatory resorption. The teeth that were moved immediately after the trauma had lesser degree of replacement resorption compared with those that were extruded 7 days after the trauma. [source]

    Dental trauma that require fixation in a children's hospital

    Timothy Bruns
    Complex injuries to permanent teeth and their periodontium require immediate repositioning and stabilization. Many of these emergencies are treated by pediatric dental residents at the Women and Children's Hospital of Buffalo, Buffalo, New York. The purpose of this study was to characterize these complex injuries of permanent teeth that require emergency treatment in a Children's Hospital. All of the cases of dental trauma which had involved permanent teeth and which had been treated with a splint in 2001 and 2002 were reviewed. There were 79 patients that were between 5 and 19 years of age with twice as many males (54) as females (25). The number of males increased from childhood (5,10 years) to early adolescence (11,15 years) and then decreased rapidly in late adolescence (16,19 years), whereas the number of females decreased steadily with age. Most of the incidents occurred during the summer months (72%), particularly in June and July (42%), and Fridays and Saturdays were the busiest days of the week. Most of the injuries were caused by organized and recreational sporting activities (39%) and accidental falls (33%), followed by interpersonal violence (15%) and a few motor vehicle accidents (7%). The 173 permanent tooth injuries were mostly luxations (62%) or avulsions (20%), with only a few fractures of the alveolar bone (5%) or tooth root (1%). Most of the displacements were lateral luxations (40%) or extrusions (18%) with only a few intrusions (3%). These injuries most commonly afflicted the maxillary central incisors (54%), followed by the maxillary laterals (18%) and mandibular centrals (17%). The emergency treatment that was provided at the Children's Hospital included replantation and repositioning, and the placement of a semi-rigid or flexible splint. [source]

    Hypothermic insult to the periodontium: a model for the study of aseptic tooth resorption

    C. W. Dreyer
    Abstract , The aim of the current investigation was to define an animal model for the study of hard tissue resorption by examining the responses of the periodontal ligament (PDL) to both single and multiple episodes of hypothermic injury to the crowns of rat teeth. A group of 12 male rats weighing 200,250 g were anesthetized, and pellets of dry ice (CO2) were applied once to the crowns of the right first maxillary molars for continuous periods of 10 or 20 min. Animals were sacrificed at 2, 7, 14 and 28 days and tissues were processed for routine histological examination. A second group of eight animals and a third group of 12 animals were subjected to three applications of dry ice over a period of 1 week and sacrificed at 2 and 14 days respectively after the final application. In addition to thermal insult, the periodontium of teeth from a fourth group of six rats was subjected to mechanical trauma. Examination of the sections from the group undergoing a single freezing episode revealed that, by 1 week, shallow resorption lacunae had appeared on the root surface. These became more extensive after 14 days. At the same time hyaline degeneration was evident in the PDL. Within this group, teeth subjected to the longer 20-min application times generally showed more extensive injuries. By 28 days, evidence of repair was observed with reparative cementum beginning to line the resorption lacunae in the root dentin. Sections from animals subjected to multiple episodes of thermal trauma and those subjected to additional mechanical insult showed more extensive external root resorption than those from single-injury animals. It was concluded that low temperature stimuli applied to the crowns of rat molars were capable of eliciting a sterile degenerative response in the PDL which, in turn, resulted in external root resorption. Furthermore, the degree of this tissue injury was commensurate with the duration and number of exposures to the trauma. The results also indicated that progression of the resorptive process required periodic exposure to the injury, in the absence of which repair to the damaged root occurred. [source]

    Role of Wnt signaling in the biology of the periodontium

    Scott M. Rooker
    Abstract Continuously erupting teeth have associated with them a continuously regenerating periodontal ligament, but the factors that control this amazing regenerative potential are unknown. We used genetic strategies to show that the periodontal ligament arises from the cranial neural crest. Despite their histological similarity, the periodontal ligament of continuously erupting incisor teeth differs dramatically from the periodontal ligament of molar teeth. The most notable difference was in the distribution of Wnt responsive cells in the incisor periodontal ligament, which coincided with regions of periodontal ligament cell proliferation. We discuss these findings in the context of dental tissue regeneration. Developmental Dynamics 239:140,147, 2010. © 2009 Wiley-Liss, Inc. [source]

    Elevated levels of collagen cross-link residues in gingival tissues and crevicular fluid of teeth with periodontal disease

    Søren Jepsen
    Lysylpyridinoline (LP) and hydroxylysylpyridinoline (HP) are collagen cross-link residues. Lysylpyridinoline is present in most tissues, whereas LP is present mainly in mineralized tissue. Both are elevated in tissue with increased collagen resorption. The purpose of this investigation was to assess if the concentrations of LP and HP are elevated in gingiva and gingival crevicular fluid (GCF) of teeth with advanced periodontitis (AP). We investigated human gingival biopsies of healthy teeth (n = 19) and teeth with AP (n = 43) in 49 individuals. Samples of GCF from 54 teeth with AP were collected in seven patients and compared with samples from 11 patients with experimentally induced gingivitis. Levels of LP and HP were measured by HPLC and fluorescence detection. Gingival concentrations of HP but not LP around teeth with advanced periodontitis were significantly elevated compared with teeth with healthy periodontium. While significant amounts of HP and LP were measurable in the GCF of teeth with AP, no HP and LP was identified 3 months following non-surgical periodontal therapy of the teeth or in fluid from teeth subjected to experimentally induced gingivitis. Elevated concentrations of HP and LP in GCF may serve as indicators of ongoing destruction of periodontal tissues and alveolar bone in advanced periodontitis. [source]

    Sonic and ultrasonic scalers in periodontal treatment: a review

    T Arabaci
    Abstract:, Periodontal therapy aims at arresting periodontal infection and maintaining a healthy periodontium. The periodic mechanical removal of subgingival microbial biofilms is essential for controlling inflammatory periodontal disease. Mechanical periodontal therapy consists of scaling, root planing and gingival curettage. The sonic and ultrasonic scalers are valuable tools in the prevention of periodontal disease. The vibration of scaler tips is the main effect to remove the deposits from the dental surface, such as bacterial plaque, calculus and endotoxin. However, constant flushing activity of the lavage used to cool the tips and cavitational activity result in disruption of the weak and unattached subgingival plaque. The aim of the study was to review the safety, efficacy, role and deleterious side-effects of sonic and ultrasonic scalers in mechanical periodontal therapy. [source]

    Long-term prognosis of crown-fractured permanent incisors.

    The effect of stage of root development, associated luxation injury
    Objectives. The aim of the present study was to investigate pulp healing responses following crown fracture with and without pulp exposure as well as with and without associated luxation injury and in relation to stage of root development. Patient material and methods. The long-term prognosis was examined for 455 permanent teeth with crown fractures, 352 (246 with associated luxation injury) without pulpal involvement and 103 (69 with associated luxation injury) with pulp exposures. Initial treatment for all patients was provided by on-call oral surgeons at the emergency service, University Hospital (Rigshospitalet), Copenhagen. In fractures without pulpal involvement, dentin was covered by a hard-setting calcium hydroxide cement (Dycal®), marginal enamel acid-etched (phosphoric acid gel), then covered with a temporary crown and bridge material. In the case of pulp exposure, pulp capping or partial pulpotomy was performed. Thereafter treatment was identical to the first group. Patients were then referred to their own dentist for resin composite restoration. Results. Patients were monitored for normal pulp healing or healing complications for up to 17 years after injury (x = 2·3 years, range 0·2,17·0 years, SD + 2·7). Pulp healing was registered and classified into pulp survival with no radiographic change (PS), pulp canal obliteration (PCO) and pulp necrosis (PN). Healing was related to the following clinical factors: stage of root development at the time of injury, associated damage to the periodontium at time of injury (luxation) and time interval from injury until initial treatment. Crown fractures with or without pulp exposure and no concomitant luxation injury showed PS in 99%, PCO in 1% and PN in 0%. Crown fractures with concomitant luxation showed PS in 70%, PCO in 5% and PN in 25%. An associated damage to the periodontal ligament significantly increased the likelihood of pulp necrosis from 0% to 28% (P < 0·001) in teeth with only enamel and dentin exposure and from 0% to 14% (P < 0·001) in teeth with pulp exposure. Conclusions. In the case of concomitant luxation injuries, the stage of root development played an important role in the risk of pulp necrosis after crown fracture. However, the primary factor related to pulp healing events after crown fracture appears to be compromised pulp circulation due to concomitant luxation injuries. [source]

    Periodontal growth factors and tissue carriers: Biocompatibility and mitogenic efficacy in vitro

    Claudio Cesari
    Clinical research has long been testing techniques of integrating biomaterials with many external factors, such as simple proteins or more complicated devices, in order to achieve the restitutio ad integrum of periodontium. This study assessed the in vitro effectiveness of platelet derivate growth factor-BB (PDGF) and insulin growth factor I (IGF); the biocompatibility of materials like Paroguide, Oclastim membranes, Gingistat sponges, Surgiplaster, and Capset; and their efficacy as carriers for the platelet derivate growth factor-BB (PDGF) and insulin growth factor I (IGF). Fibroblasts from the human periodontal ligament were incubated with growth factors free or vehiculated. Mitogenic effect was evaluated by measuring the growth rate and biocompatibility by observing cell morphology at SEM. PDGF was the most effective in stimulating cell proliferation both in solution (p < 0.001) and vehiculated (p < 0.01). Surgiplaster and Capset were more biocompatible; however, final analysis to assess their efficacy as carriers failed to disclose significant differences between experimental findings and control. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source]

    Growth Hormone Induces Bone Morphogenetic Proteins and Bone-Related Proteins in the Developing Rat Periodontium

    Huika Li
    Abstract The hypothesis that growth hormone (GH) up-regulates the expression of enzymes, matrix proteins, and differentiation markers involved in mineralization of tooth and bone matrices was tested by the treatment of Lewis dwarf rats with GH over 5 days. The molar teeth and associated alveolar bone were processed for immunohistochemical demonstration of bone morphogenetic proteins 2 and 4 (BMP-2 and -4), bone morphogenetic protein type IA receptor (BMPR-IA), bone alkaline phosphatase (ALP), osteocalcin (OC), osteopontin (OPN), bone sialoprotein (BSP), and E11 protein (E11). The cementoblasts, osteoblasts, and periodontal ligament (PDL) cells responded to GH by expressing BMP-2 and -4, BMPR-IA, ALP, OC, and OPN and increasing the numbers of these cells. No changes were found in patterns of expression of the late differentiation markers BSP and E11 in response to GH. Thus, GH evokes expression of bone markers of early differentiation in cementoblasts, PDL cells, and osteoblasts of the periodontium. We propose that the induction of BMP-2 and -4 and their receptor by GH compliments the role of GH-induced insulin-like growth factor 1 (IGF-1) in promoting bone and tooth root formation. [source]

    Role of serum cytokines tumour necrosis factor- , and interleukin-6 in the association between body weight and periodontal infection

    Tuomas Saxlin
    Abstract Aim: To study the role of serum cytokines tumour necrosis factor , (TNF- ,) and interleukin 6 (IL-6) as potential mediators in the association between body weight and periodontal infection among an adult population. Material and Methods: This study was based on a subpopulation of the Health 2000 Health Examination Survey, which included dentate non-diabetic, non-rheumatic subjects, aged between 45 and 64 years, who had never smoked and whose serum levels of TNF- , and IL-6 were analysed and whose periodontal status was clinically determined (effective n=425). The number of teeth with periodontal pockets of 4 mm or more and the number of teeth with periodontal pockets of 6 mm or more were used as outcome variables. Relative risks and 95% confidence intervals were estimated using Poisson regression models. Results: Serum IL-6, but not TNF- , associated with teeth with deepened periodontal pockets. Multivariate models showed that IL-6, but not TNF- ,, could mediate the effect of body weight on periodontium. Conclusion: In this population of non-diabetic and non-rheumatic subjects, who had never smoked, serum IL-6 was associated with periodontal infection. The results suggest that serum IL-6 could be one mediating factor that connects body weight and periodontal infection. [source]

    Clinical changes in periodontium during pregnancy and post-partum

    Mervi Gürsoy
    Abstract Background and Aim: Pregnancy has been presented to increase susceptibility to gingival inflammation. It is unclear whether pregnancy gingivitis exposes or proceeds to periodontitis. We examined longitudinally the severity of periodontal changes during pregnancy and post-partum, and compared the findings with an age-matched group of non-pregnant women. Material and Methods: Thirty generally healthy, non-smoking women at an early phase of their pregnancy and 24 non-pregnant women as controls were recruited. The pregnant group was examined three times during pregnancy and twice during post-partum, and the non-pregnant group three times, once per subsequent month. At each visit, visible plaque index (VPI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were measured from six sites per tooth. Results: In the pregnant group, BOP and PPD increased simultaneously without relation to plaque between the first and second trimesters, and thereafter decreased during subsequent visits. No changes were detected in CAL during the study period. In the non-pregnant group, BOP stayed invariable during the follow-up and correlated with the amount of plaque. Neither periodontal pocket formation nor significant changes in attachment levels were observed. Conclusion: Based on this study, changes in clinical parameters during pregnancy are reversible, indicating that pregnancy gingivitis does not predispose or proceed to periodontitis. [source]

    Cigarette smoking and periodontal disease among 32-year-olds: a prospective study of a representative birth cohort

    W. Murray Thomson
    Abstract Background: Smoking is recognized as the primary behavioural risk factor for periodontal attachment loss (AL), but confirmatory data from prospective cohort studies are scarce. Aim: To quantify the association between cigarette smoking patterns and AL by age 32. Methods: Periodontal examinations were conducted at ages 26 and 32 in a longstanding prospective study of a birth cohort born in Dunedin (New Zealand) in 1972/1973. Longitudinal categorization of smoking exposure was undertaken using data collected at ages 15, 18, 21, 26 and 32. Results: Complete data were available for 810 individuals of whom 48.9% had ever smoked (31.5% were current smokers). Compared with never-smokers, long-term smokers (and other age-32 smokers) had very high odds ratios (ORs of 7.1 and 5.7, respectively) for having 1 +sites with 5 +mm AL, and were more likely to be incident cases after age 26 (ORs of 5.2 and 3.2, respectively). Two-thirds of new cases after age 26 were attributable to smoking. There were no significant differences in periodontal health between never-smokers and those who had quit smoking after age 26. Conclusions: Current and long-term smoking in young adults is detrimental to periodontal health, but smoking cessation may be associated with a relatively rapid improvement in the periodontium. [source]

    Thickness of gingiva in association with age, gender and dental arch location

    K. L. Vandana
    Abstract Background: It has been long known that the clinical appearance of healthy marginal periodontium differs from subject to subject and even among different tooth types. Many features are genetically determined; others seem to be influenced by tooth size, shape and position and biological phenomena such as gender, growth and age. Aim: The purpose of this study was to determine the thickness of facial gingiva among Indians and its association with age, gender and dental arch. Methods: The study group included 16 males and 16 females with an age range of 16,38 years. Gingival thickness was assessed in the maxillary and mandibular anteriors by transgingival probing. Results: It was observed that the younger age group had significantly thicker gingiva than that of the older age group. The gingiva was found to be thinner in females than males and, in the mandibular arch than the maxilla. Conclusion: In the present study, it was concluded that gingival thickness varies according to age, gender and dental arch. [source]

    Susceptibility of GTR-regenerated periodontal attachment to ligature-induced periodontitis

    An experiment in the monkey
    Abstract Aim: This study aimed to compare the susceptibility of guided tissue regeneration (GTR)-regenerated periodontal attachment to ligature-induced periodontitis with that of the pristine periodontium. Methods: Periodontal breakdown was produced in four monkeys by the placement of orthodontic elastics around experimental teeth (test teeth). During a flap operation, the root surfaces were scaled and planed, and a notch indicating the apical termination of scaling and root planing was made in the root surface. Following resection of the crowns and endodontic treatment, an e-PTFE membrane was adapted over the roots. Subsequently, the flaps were sutured to complete closure of the wound (submerged). At membrane removal after 5 weeks, the crowns of the contralateral teeth serving as controls were resected, and the roots treated endodontically during a flap operation. Artificial composite crowns were then placed on both test and control roots. After 3 months of tooth cleaning, cotton floss ligatures were placed passively around both test and control teeth for a period of 6 months. Two weeks later the animals were sacrificed. Results: Histological analysis demonstrated that the instrumented root surfaces of the test teeth were covered by newly formed cementum of the reparative, cellular, extrinsic and intrinsic fiber type, while the cementum on the controls was mainly acellular extrinsic fiber cementum. Histometric assessments demonstrated that similar attachment loss had occurred on test (1.0±0.5 mm) and control roots (1.0±0.4 mm) during the 6 months of ligature-induced plaque accumulation. Conclusion: The results indicate that teeth with a periodontal attachment apparatus formed by GTR is not more susceptible to periodontitis than those with a pristine periodontium. [source]

    The association of gingivitis and periodontitis with ischemic stroke

    Christof E. Dörfer
    Abstract Objectives: The aim of this study was to assess the associations of different periodontal parameters with cerebral ischemia. Methods: In a case,control study, 303 consecutive patients with ischemic stroke or transient ischemic attack, and 300 representative population controls received a complete clinical and radiographic dental examination. Patients were examined on average 3 days after ischemia. The individual mean clinical attachment loss measured at four sites per tooth was used as indicator variable for periodontitis. Results: Patients had higher clinical attachment loss than population (p<0.001). After adjustment for age, gender, number of teeth, vascular risk factors and diseases, childhood and adult socioeconomic conditions and lifestyle factors, a mean clinical attachment loss >6 mm had a 7.4 times (95% confidence interval 1.55,15.3) a gingival index >1.2 a 18.3 times (5.84,57.26) and a radiographic bone loss a 3.6 times (1.58,8.28) higher risk of cerebral ischemia than subjects without periodontitis or gingivitis, respectively. Conclusion: Periodontitis is an independent risk factor for cerebral ischemia and acute exacerbation of inflammatory processes in the periodontium might be a trigger for the event of cerebral ischemia. [source]

    Influence of sex hormones on the periodontium

    Paulo Mascarenhas
    Abstract Objectives: Sex hormones have long been considered to play an influential role on periodontal tissues, bone turnover rate, wound healing and periodontal disease progression. The objectives of this review article are to (1) address the link between sex hormones and the periodontium, (2) analyse how these hormones influence the periodontium at different life times and (3) discuss the effects of hormone supplements/replacement on the periodontium. Materials and Methods: Two autonomous searches were performed in English language utilizing Medline, Premedline and Pubmed as the online databases. Publications up to 2002 were selected and further reviewed. In addition, a manual search was also performed including specific related journals and books. Results: It is certain that sexual hormones play a key role in periodontal disease progression and wound healing. More specifically, these effects seem to differentiate by gender as well as lifetime period. In addition, the influence of sex hormones can be minimized with good plaque control and with hormone replacement. Conclusion: Despite profound research linking periodontal condition with sex hormones kinetics, more definitive molecular mechanisms and therapy still remain to be determined. Zusammenfassung Männliche und weibliche Sexualhormone wurden schon lange einen wichtigen Einfluss auf das parodontale Gewebe, die Knochenumsatzrate, die Wundheilung und die parodontale Erkrankungsprogression ausübend betrachtet. Der Einfluss dieser Hormone auf das Parodontium unterscheidet sich zu verschiedenen physiologischen Phasen (z.B. Pubertät, Schwangerschaft, post Menopause) und mit der Einnahme von Pharmaka (z.B. Antikonzeptiva, Hormonsubstitution). Deshalb ist der Zweck dieses Reviewartikels (1) die Beziehung zwischen Sexualhormonen und dem Parodontium zu beschreiben, (2) die Analyse des Einflusses dieser Hormone auf das Parodontium zu unterschiedlichen Lebenszeiten und (3) die Effekte von Hormonunterstützung/substitution auf das Parodontium zu diskutieren. Résumé On a longtemps considéré que les hormones sexuelles, aussi bien masculines que féminines, jouaient un rôle important sur les tissus parodontaux, le taux de remaniement osseux, la cicatrisation et la progression de la maladie parodontale. L'influence de ces hormones sur le parodonte est différente en fonction des divers conditions physiologiques (par exemple, la puberté, la grossesse, et après la ménopause) et les prises de médicaments (par exemple, la pillule contraceptive et les traitements hormonaux de substitution). Aussi, cette revue critique de la littérature se propose (1) de faire le point sur les liens entre les hormones sexuelles et le parodonte (2) d' analyser la façon dont ces hormones influencent le parodonte lors des différentes étapes de la vie, et (3) discuter les effets des hormones de substitution sur le parodonte. [source]

    Prevalence of Actinobacillus actinomycetemcomitans in an ethnic adult Chinese population

    Kai Soo Tan
    Abstract Aim: The aim of this study was to determine the prevalence and the structure of the leukotoxin promoter region of Actinobacillus actinomycetemcomitans in an ethnic Chinese population. Method: Subgingival plaque samples were collected from 42 patients with moderate to advanced periodontitis and 50 periodontally healthy patients. A. actinomycetemcomitans was detected directly from the crude subgingival plaque by PCR using leukotoxin gene specific primers. The presence of A. actinomycetemcomitans was determined by a single 285 bp PCR amplicon. Results:A. actinomycetemcomitans was found to be present in the subgingival plaque of 68 out of a total of 92 patients examined (74%). 29 out of the 42 periodontitis patients tested were carriers of A. actinomycetemcomitans (69%). Among the periodontally healthy patients studied, 39 out of 50 subjects possessed the bacteria (78%). PCR analysis of the promoter region of the ltx operon revealed that none of the 42 moderate to advanced periodontitis patients examined harboured A.actinomycetemcomitans strains with the JP2-like promoter of the ltx operon, known to enhance leukotoxin expression. 2 out of the 27 advanced periodontitis patients clinically diagnosed as suffering from rapidly progressive periodontitis were found to be carriers of the mildly toxic strain of A. actinomycetemcomitans with the characteristic 652-like promoter. Conclusions: The high prevalence of A. actinomycetemcomitans, regardless of whether the subgingival samples were analysed from patients with healthy or diseased periodontium suggests that this bacterial species is part of the normal oral flora of ethnic Chinese. Our preliminary results also suggested that subjects who harboured the mildly toxic strain of A. actinomycetemcomitans were potentially susceptible to aggressive forms of periodontitis. Zusammenfassung Das Ziel dieser Studie war es, in einer ethnischen Population von Chinesen die Prävalenz von Actinobacillus actinomycetemcomitans und die Struktur der Leukotoxin-Promoterregion zu bestimmen. Von 42 Patienten mit moderater bis fortgeschrittener Parodontitis und 50 parodontal gesunden Patienten wurden subgingivale Plaqueproben entnommen. A. actinomycetemcomitans wurde direkt in der unbehandelten subgingivalen Plaque durch PCR unter Verwendung eines Leukotoxingen-spezifischen Primers nachgewiesen. Das Vorhandensein von A. actinomycetemcomitans wurde mittels eines einzigen 285 bp-PCR-Amplikons bestimmt. Es wurde A. actinomycetemcomitans bei 68 von 92 untersuchten Patienten (74%) vorgefunden. 29 von 42 getesteten Parodontitispatienten waren Träger von A. actinomycetemcomitans (69%). Unter den Studierten parodontal gesunden Patienten besaßen 39 von 50 Personen das Bakterium (78%). Die PCR-Analyse der Promoterregion des ltx -Operons zeigte, dass keiner der 42 untersuchten Patienten mit moderater bis fortgeschrittener Parodontitis den A. actinomycetemcomitans mit dem JP2-ähnlichen Promoter des ltx -Operons, welches die Leukotoxinexpression verstärkt, besaß. Bei 2 der 27 Patienten mit fortgeschrittener Parodontitis wurde klinisch eine rasch fortschreitende Parodontitis diagnostiziert und es wurde der mit geringer Toxizität versehene Stamm des A. actinomycetemcomitans mit dem charakteristischen 652-ähnlichen Promoter vorgefunden. Bedingt durch die hohe Prävalenz von A. actinomycetemcomitans unabhängig davon, ob die Proben von Patienten mit gesundem oder erkranktem Parodontium stammen, lässt sich annehmen, dass diese Bakterienspezies bei ethnischen Chinesen ein Teil normalen Mundflora ist. Unsere vorläufigen Resultate lassen auch annehmen, dass Personen, die den mit geringer Toxizität versehenen Stamm des A. actinomycetemcomitans tragen eine potentielle Anfälligkeit für aggressive Formen der Parodontitis besitzen. Résumé Le but de l'étude présente a été de déterminer la fréquence globale et la structure de la région promoteur de leukotoxine de l'Actinobacillus actinomycetemcomitans (A.a.) dans une population chinoise. Des échantillons de plaque dentaire sous-gingivale ont été prélevés chez 42 patients avec parodontite modérée à avancée et chez 50 patients sains. L'A.a. a été détecté directement dans la plaque sous-gingivale par PCR en utilisant les sites spécifiques de gènes leukotoxines. La présence de l'A.a. a été déterminée par un amplicon PCR de 285 bp. L'A.a. a été décelé dans la plaque sous-gingivale de 68 des 92 patients examinés (74%). 29 des 42 patients avec parodontite ont été reconnus comme porteurs d'A.a. (69%). Parmi les patients sains étudiés, 39 des 50 sujets étaient porteurs de la bactérie (78%). L'analyse PCR de la région promoteur de operon ltx a révélé que des 42 patients avec parodontite modéréà avancée aucun n'avaient de souche A.a. avec le promoteur ressemblant au JP2 de l'operon ltx, reconnu pour acroître la leukotoxine. 2 des 27 patients avec parodontit avancée souffraient d'une parodontite progressant rapidement et étaient porteurs d'une souche moyennement toxique d'A.a. avec la caractéristique du promoteur ressemblant au 652. La fréquence globale importante d'A.a., sans tenir compte si les échantillons sous-gingivaux ont été analysés de patients avec un parodonte sain ou malade, suggère que ces espèces bactériennes font partie de la flore buccale normale de l'ethnie chinoise. Ces résultats indiquent également que les porteurs de la souche peu toxique d'A.a. seraient potentiellement susceptibles à des formes de parodontite agressive. [source]

    Adverse effects of arecoline and nicotine on human periodontal ligament fibroblasts in vitro

    Yu-Chao Chang
    Abstract Background, aims: The habit of betel nut chewing impinges on the daily lives of approximately 200 million people. Betel quid chewers have a higher prevalence of periodontal diseases than non-chewers. This study examined the pathobiological effects of arecoline, a major component of the betel nut alkaloids, on human periodontal ligament fibroblasts (PDLF) in vitro. Method: Cell viability, proliferation, protein synthesis, and cellular thiol levels were used to investigate the effects of human PDLF exposed to arecoline levels of 0 to 200 ,g/ml. In addition, nicotine was added to test how it modulated the effects of arecoline. Results: Arecoline significantly inhibited cell proliferation in a dose-dependent manner. At concentrations of 10 and 30 ,g/ml, arecoline suppressed the growth of PDLF by 20% and 50% (p<0.05), respectively. Arecoline also decreased protein synthesis in a dose-dependent manner during a 24-h culture period. A 100 ,g/ml concentration level of arecoline significantly inhibited protein synthesis to only 50% of that in the untreated control (p<0.05). Moreover, arecoline significantly depleted intracellular thiols in a dose-dependent manner. At concentrations of 25 ,g/ml and 100 ,g/ml, arecoline depleted about 18% and 56% of thiols (p<0.05), respectively. This suggests that arecoline itself might augment the destruction of periodontium associated with betel nut use. Furthermore, the addition of nicotine acted with a synergistic effect on the arecoline-induced cytotoxicity. At a concentration of 60 ,g/ml, arecoline suppressed the growth of PDLF by about 33%, and 5 mM nicotine enhanced the arecoline-induced cytotoxic response to cause about 66% cell death. Conclusion: During thiol depletion, arecoline may render human PDLF more vulnerable to reactive agents within cigarettes. Taken together, people who combine habits of betel nut chewing with cigarette smoking could be more susceptible to periodontium damage than betel nut chewing alone. Zusammenfassung Zielsetzung: Das Kauen von Betelnüssen gehört zum Alltag von ungefähr 200 Millionen Menschen. Betelnußkauer weisen eine höhere Prävalenz von Parodontalerkrankungen auf als Personen, die keine Betelnüsse konsumieren. In dieser Studie sollte der pathobiologische Effekt des Arekolins, das die Hauptkomponente des Betelnußalkaloides darstellt, auf menschliche Desmodontalfibroblasten (PDLF) in vitro untersuchen. Material und Methoden: Zellvitalität, Proliferationsrate, Proteinsynthese und zelluläre Thiolspiegel wurden genutzt, um zu untersuchen, welche Auswirkungen eine Exposition der PDLF gegenüber Arekolinspiegeln von 0 bis 200 ,g/ml hat. Zusätzlich wurde Nikotin beigefügt, um festzustellen wie das Nikotin den Effekt des Arekolins beeinflußt. Ergebnisse: Arekolin hemmt die Zellproliferation signifikant in dosisabhängiger Weise. Bei Konzentrationen von 10 und 30 ,g/ml unterdrückt Arekolin das Wachstum der PDLF um 20% bzw. 50% (p<0.05). Arekolin unterdrückt ebenfalls dosisabhängig die Proteinsynthese während der 24-stündigen Kultivierungsperiode. Ein Arekolinspiegel von 100 ,g/ml reduzierte die Proteinsynthese auf 50% im Vergleich zur unbehandelten Kontrollkultur (p<0.05). Auch die intrazellulären Thiolspiegel wurden dosisabhängig reduziert. Bei Konzentrationen von 25 und 100 ,g/ml wurden die Thiolspiegel um 18% bzw. 56% reduziert (p<0.05). Bei einer Konzentration von 60 ,g/ml unterdrückte das Arekolin das PDLF-Wachstum um 33%. Die Zugabe von 5 mM Nikotin verstärkte die durch Arekolin induzierte zytotoxische Wirkung, so daß es zum Zelltot von 66% kam. Schlußfolgerungen: Es scheint, daß Arekolin selbst zu der Schädigung des Parodonts beiträgt, die der Betelnuß zugeschreiben wird. Außerdem deuten die Ergebnisse darauf hin, daß Personen, die Betelnußkauen mit Nikotinkonsum kombinieren, empfindlicher für Schädigungen des Parodonts sind als solche, die nur Betelnüsse kauen. Während der Inaktivierung des Thiols könnte das Arekolin PDLF verletzlicher für andere reaktive Substanzen wie Nikotin machen. Résumé L'habitude de mastiquer de la noix de betel affecte la vie quotidienne de près de 200 millions de personnes. Les mâcheurs de betel présentent une prévalence plus élevée de maladies parodontales. Cette étude examine les effets pathologiques de l'arécoline, un composant majeur des alcaloïdes de la noix de betel, sur des fibroblastes du ligament parodontal humain (PDLF) in vitro. La viabilité cellulaire, la prolifération, la synthèse protéique, et les niveaux cellulaires de thiol ont été utilisés pour observer les effets de l'exposition de PDLF humains à des taux d'arécoline de 0 à 200 ,g/ml. De plus, de la nicotine fut ajouté pour tester la façon dont cela modulait les effets de l'arécoline. L'arécoline inhibait significativement la prolifération cellulaire de façon dose dépendante. A des concentrations de 10 à 30 ,g/ml, l'arécoline supprime la croissance des fibroblastes par 20 et 50% (p<0.05), respectivement. L'arécoline dimunuait également la synthèse des protéines de façon dose dépendante pendant une période de culture de 24 h. Une concentration de 100 ,g/ml d'arécoline inhibit la synthèse protéique à seulement 50% de celle du groupe controle non traité (p<0.05). De plus, l'arécoline réduit les thiols intracellulaires de façon dose dépendante. A des concentrations de 25 ,g/ml et 100 ,g/ml, l'arécoline réduit environ 18 à 56% des thiols, respectivement (p<0.05). Cela suggère que l'arécoline, elle même, peut augmenter la destruction du parodonte en association avec l'utilisation de noix de betel. De plus, l'addition de nicotine entrainait un effet synergique sur la cytotoxicité induite par l'arécoline. A une concentration de 60 ,g/ml, l'arécoline supprimait la croissance des PDLF d'environ 33% et 5 mM de nicotine augmentait cette réponse cytotoxique induite par l'arécoline, jusqu'à entrainer 66% de morts cellulaires. Lors de la réduction des thiols, l'arécoline pourrait rendre les PDLF humains plus vulnérables à des agents réactifs entrant dans la composition des cigarettes. Pris ensemble, les gens qui combinent des habitudes de mastication de noix de betel et de tabagisme, pourrait être plus susceptibles à des dommages parodontaux, que les gens qui utiliserait uniquement la noix de betel, mais sans fumer. [source]

    The effect of three different periodontal pre-treatment procedures on the success of telescopic removable partial dentures

    R. Polansky
    summary, In this prospective study, 120 teeth consisting of maxillary and mandibular canines and premolars were divided into three groups each containing 40 teeth. The teeth were assigned randomly in quadrants to three different periodontal treatment protocols. The first group was treated with professional prophylaxis only. The second group received additional deep scaling. With the third group, additional surgical periodontal flap surgery and scaling was performed. Both papillary bleeding index (PBI) and probing depth (PD) were evaluated before, during and after treatment. During the subsequent prosthetic treatment phase all teeth were then used as telescope abutments supporting a removable prosthesis. The documentation of the attachment level (AL) was then used as a clinical parameter. One year after the incorporation of telescopic removable partial dentures (RPDs), PD, PBI and AL were again evaluated. The resulting periodontal parameters were compared between the different groups using the general linear model (GLM) repeated measures and the Kruskal,Wallis test for non-parametric variables. Differences within the three treatment groups were determined using the t -test, e.g. the Wilcoxon test for dependent variables (P < 0·05). A significant decrease in inflammatory indices (PBI) was found for all types of periodontal treatment (P < 0·03 for all groups). Additionally, the reduction in PD was significant for all of the three groups (P < 0·001 for all groups). The greatest reduction in PD was observed in the group in which a surgical approach was used. Evaluation of the attachment level after the incorporation of the telescopic RPDs showed that tooth position did not influence the periodontal prognosis and that the use of telescopic RPDs exerted no ascertainable negative influence on the periodontium of the abutment teeth. [source]

    Localization of SOST/sclerostin in cementocytes in vivo and in mineralizing periodontal ligament cells in vitro

    A. Jäger
    Jäger A, Götz W, Lossdörfer S, Rath-Deschner B. Localization of SOST/sclerostin in cementocytes in vivo and in mineralizing periodontal ligament cells in vitro. J Periodont Res 2009; doi: 10.1111/j.1600-0765.2009.01227.x. © 2009 John Wiley & Sons A/S Background and Objective:, Cementum and bone are rather similar hard tissues, and osteocytes and cementocytes, together with their canalicular network, share many morphological and cell biological characteristics. However, there is no clear evidence that cementocytes have a function in tissue homeostasis of cementum comparable to that of osteocytes in bone. Recent studies have established an important role for the secreted glycoprotein sclerostin, the product of the SOST gene, as an osteocyte-derived signal to control bone remodelling. In this study, we investigated the expression of sclerostin in cementocytes in vivo as well as the expression of SOST and sclerostin in periodontal ligament cell cultures following induction of mineralization. Material and Method:, Immunolocalization of sclerostin was performed in decalcified histological sections of mouse and human teeth and alveolar bone. Additionally, periodontal ligament cells from human donors were cultured in osteogenic conditions, namely in the presence of dexamethasone, ascorbic acid and ,-glycerophosphate, for up to 3 wk. The induction of calcified nodules was visualized by von Kossa stain. SOST mRNA was detected by real-time PCR, and the presence of sclerostin was verified using immunohistochemistry and western blots. Results:, Expression of sclerostin was demonstrated in osteocytes of mouse and human alveolar bone. Distinct immunolocalization in the cementocytes was shown. In periodontal ligament cultures, following mineralization treatment, increasing levels of SOST mRNA as well as of sclerostin protein could be verified. Conclusion:, The identification of SOST/sclerostin in cementocytes and mineralizing periodontal ligament cells adds to our understanding of the biology of the periodontium, but the functional meaning of these findings can only be unravelled after additional in vitro and in vivo studies. [source]

    Expression of matrix metalloproteinase-1, matrix metalloproteinase-2 and extracellular metalloproteinase inducer in human periodontal ligament cells stimulated with interleukin-1beta

    J. Xiang
    Background and Objectives: Matrix metalloproteinases (MMPs), produced by both infiltrating and resident cells of the periodontium, play important roles in physiologic and pathologic events. Both interleukin-1beta and extracellular MMP inducer can stimulate the expression of MMPs, which in turn leads to breakdown of the periodontium. However, it is currently unknown whether interleukin-1beta up-regulates MMPs through stimulating the expression of extracellular MMP inducer. The aims of this study were to investigate the effect of interleukin-1beta on the expression of MMP-1, MMP-2 and extracellular MMP inducer in human periodontal ligament cells and to evaluate whether the regulation of MMP-1 and MMP-2 by this cytokine occurred through an effect on extracellular MMP inducer expression. Material and Methods: Cultured human periodontal ligament cells were treated with varying concentrations (0.01,10 ng/mL) of interleukin-1beta at for 6, 12 and 24 h. Reverse transcription,polymerase chain reaction, enzyme-linked immunosorbent assay, gelatin zymography and western blotting were performed to measure the mRNA and protein levels of MMP-1, MMP-2 and extracellular MMP inducer. Results: Basal levels of mRNA and protein for MMP-1, MMP-2 and extracellular MMP inducer were detected in untreated human periodontal ligament cells. Interleukin-1beta significantly up-regulated the expression of MMP-1 and MMP-2 mRNA and protein (p < 0.05); however, the levels of mRNA and protein for extracellular MMP inducer were not significantly different (p > 0.05). In the culture medium, the concentration of MMP-1 was also increased significantly, but the concentration of MMP-1 was not related to the concentration of extracellular MMP inducer (R2 = 0.2538, p > 0.05). Conclusion: Interleukin-1beta up-regulated the levels of MMP-1 and MMP-2, but it did not alter the expression of extracellular MMP inducer. Expression of MMP-1 and MMP-2 might be elevated by interleukin-1beta and extracellular MMP inducer via two different signal pathways. [source]

    Extracellular neutrophil traps in periodontitis

    L. Vitkov
    Background and Objective:, Chronic periodontitis, the chronic inflammatory disease of the periodontium, is caused by bacteria and is characterized by an influx of neutrophils into the gingival crevice. Recently, a ,new' extracellular neutrophil defense mechanism , neutrophil extracellular traps , has been described. However, their role in periodontitis has not yet been investigated. Material and Methods:, Clinical examinations, transmission and scanning electron microscopy, as well as cytology and confocal laser-scanning microscopy, were employed to analyze gingiva biopsies and crevicular exudate from patients with chronic periodontitis. Results:, An abundance of neutrophil extracellular traps and some phagocytic neutrophils was found on the gingival pocket surface and in the purulent crevicular exudate. Finding neutrophil extracellular traps in the spontaneously effused purulent crevicular exudate clearly indicated that they are flushed from the pocket by the crevicular exudate. In cases of dispersal of subgingival plaque bacteria, their trapping by neutrophil extracellular traps in purulent crevicular exudate and on the gingival surface was demonstrated. Conclusion:, Trapping the crevicular bacteria prevents their adhesion to and invasion of the gingiva. The combination of neutrophil extracellular traps and crevicular exudate outflow appears to be a ,novel' defense mechanism for the clearance of crevicular bacteria in chronic periodontitis. [source]

    The effect of butyric acid on adhesion molecule expression by human gingival epithelial cells

    S. Takigawa
    Background and Objective:, Short-chain fatty acids, such as butyric acid, are detected in periodontal pockets and are thought to be involved in the initiation and progression of periodontal disease. In the present study, we examined the effects of butyric acid on adhesion molecule expression by human gingival epithelial cells. Material and methods:, The human gingival carcinoma cell line, Ca9-22, was cultured in media that contained different concentrations of butyric acid. Results:, Cell numbers were significantly decreased in a dose-dependent manner by butyric acid at concentrations of , 0.2 mm. The expression of intercellular adhesion molecule-1 mRNA was significantly increased 6 h after stimulation. By contrast, the expression levels of integrins ,6 and ,4 were decreased. Similar results were obtained by flow cytometry. Conclusion:, The results of the present study indicate that butyric acid alters the expression of adhesion molecules by Ca9-22 cells. The elucidation of the mechanism of action of butyric acid on the periodontium may help to clarify several aspects of the onset and progression of periodontal disease. [source]

    Expression of receptor activator of nuclear factor kappa B ligand relates to inflammatory bone resorption, with or without occlusal trauma, in rats

    Y. Yoshinaga
    Background and Objective:, Receptor activator of nuclear factor kappa B ligand (RANKL) is an important factor in osteoclast differentiation, activation and survival; however, its involvement in inflammatory bone resorption, with or without occlusal trauma, is unclear. The purpose of the present study was to investigate the distribution of RANKL-expressing cells in rat periodontium during lipopolysaccharide-induced inflammation with or without occlusal trauma. Material and Methods:, Lipopolysaccharide was injected into rat gingiva of the lower left first molar to induce inflammation. In addition, the occlusal surface of the upper left first molar of rat was raised by placing a gold inlay to induce occlusal trauma in the lower left first molars. The distribution of RANKL-expressing cells was immunohistochemically observed. Results:, In the inflammatory model, many osteoclasts were observed at the apical inter-radicular septum on day 5 and they were reduced by day 10. On the other hand, in the inflammatory model with occlusal trauma, many osteoclasts were still observed on day 10. RANKL expression was similar to the changes in osteoclast number. The expression of RANKL increased in endothelial cells, inflammatory cells and periodontal ligament cells. Conclusion:, These findings clearly demonstrated that RANKL expression on endothelial cells, inflammatory cells and periodontal ligament cells is involved in inflammatory bone resorption and the expression is enhanced by traumatic occlusion. These results suggest that RANKL expression on these cells is closely involved in the increase of osteoclasts induced by occlusal trauma. [source]

    Smoking modulates interleukin-6:interleukin-10 and RANKL:osteoprotegerin ratios in the periodontal tissues

    J. B. César-Neto
    Background and Objective:, This study evaluated the effect of smoking on the gene expression of interleukin-1,, -1ra, -6, -8 and -10, tumor necrosis factor-,, matrix metalloproteinase (MMP)-2 and -8, receptor activator of NF-,B ligand (RANKL) and osteoprotegerin, in sites with periodontitis. Material and Methods:, Gingival biopsies were divided into three groups: the healthy group (periodontally healthy subjects; n = 10); the periodontitis group [subjects with severe chronic periodontitis who never smoked (probing depth ,,7 mm) (n = 25)]; and the smoking group (subjects diagnosed with severe chronic periodontitis who smoked ,,1 pack per day for at least 10 years; n = 25). Gene and protein expressions were analyzed by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Results:, Data analysis demonstrated that, except for MMP-8 and osteoprotegerin, the levels of all factors were increased by inflammation (p < 0.001). The levels of interleukin-1,, -1ra, -6 and -8, and RANKL, were higher in smokers with periodontitis compared with controls, whereas the levels of interleukin-10, MMP-8 and osteoprotegerin were lower (p < 0.001). Smoking lowered the levels of interleukin-1,, -8, -10, tumor necrosis factor-,, MMP-8 and osteoprotegerin, and increased the levels of interleukin-6 and -1ra in sites with a comparable type of periodontitis (p < 0.001). Conclusion:, In conclusion, smoking modulates gene expression in the periodontium, and the influence of smoking on periodontal disease may involve effects of interleukin-6:interleukin-10 and RANKL:osteoprotegerin ratios. [source]

    Lipid peroxidation: a possible role in the induction and progression of chronic periodontitis

    C. C. Tsai
    Objectives:, Reactive oxygen species (ROS) are implicated in the destruction of the periodontium during inflammatory periodontal diseases. The imbalance in oxidant/antioxidant activity may be a key factor in the damaging effects of ROS. This study aimed to determine the lipid peroxidation levels in gingival crevicular fluid and saliva, and glutathione (GSH) and glutathione peroxidase (GPx) in saliva in patients with chronic periodontitis. Methods:, Gingival crevicular fluid and saliva were collected from 13 patients and 9 healthy control subjects during the preliminary study, and from 21 patients during the subsequent study. Lipid peroxidation level, GSH level and GPx activity were determined by spectrophotometric assay. Results:, The preliminary study found that when comparing patients to healthy controls, the gingival crevicular fluid samples produced the following results, respectively: higher lipid peroxidation concentration (µm) (by sites: 167.55 vs. 53.71, p < 0.0001; by subjects: 151.99 vs. 50.66, p < 0.005) and total amount (pmol) (by sites: 93.02 vs. 8.47, p < 0.0001, by subjects: 80.44 vs. 7.84, p < 0.0005). In saliva samples, lower GSH concentration (µm) (373.04 vs. 606.67, p < 0.05), higher lipid peroxidation concentration (µm) (0.66 vs. 0.13, p < 0.0005), and no difference in GPx activity were found in patients than in those of healthy controls. The subsequent study showed statistically significant (p < 0.05) improvement of clinical periodontal parameters (plaque index, gingival index, probing attachment level, probing pocket depth and gingival crevicular fluid volume), decreases in gingival crevicular fluid lipid peroxidation levels (concentration and total amount) at the sites after the completion of phase 1 periodontal treatment. Similarly, the periodontal treatment resulted in a significant decrease of lipid peroxidation concentrations (p < 0.05), increase in GSH concentration (p < 0.001), and no change in GPx activity in saliva samples. Conclusion:, The increased levels of lipid peroxidation may play a role in the inflammation and destruction of the periodontium in periodontitis. [source]

    Immunohistochemical analysis of Th1/Th2 cytokine profiles and androgen receptor expression in the pathogenesis of nifedipine-induced gingival overgrowth

    W-T. Huang
    Background:, Numerous studies have demonstrated that gingival overgrowth may be associated with androgen and cytokine expression in tissues. Objectives:, The aim of this study was to compare the expression of androgen receptor-presenting cells (AR+ cells) and Th1/Th2 cytokine [Th1: interleukin (IL)-2, interferon-, (IFN-,); Th2: IL-4, IL-10, IL-13] expression cells in tissue sections of patients with gingival overgrowth. Materials and methods:, Tissue samples were collected from patients with healthy periodontium (H group), adult periodontitis (P group), surgically extracted teeth (S group), and nifedipine-induced gingival overgrowth (NIGO group). The clinical periodontal parameters of pocket depth (PD), bleeding on probing (BOP), and plaque control record (PCR) were measured around selected sample teeth. Gingival biopsies were further processed by immunohistochemical staining method. The expressions of cells positive for AR, IL-2, IFN-,, IL-4, IL-10, and IL-13 were counted by predetermined semiquantitative methods. Results:, Our results indicated that AR, IL-2, IFN-,, IL-4, IL-10, and IL-13 were intensively expressed in the nuclei of inflammatory cells and fibroblasts of gingival connective tissue. Stronger expressions of AR, IL-2, and IFN-, were found in the NIGO group. The AR+ cells/0.01 mm2 in gingival fibroblasts were significantly higher in the NIGO group (80.2 ± 10.7) than those of the periodontitis group (52.5 ± 11.8) and control group (37.4 ± 11.3) (P < 0.05). The cytokine expression of the NIGO group showed a trend towards Th1-type expression (IL-2; P = 0.0001). In the surgically extracted tooth group, a stronger expression of Th2-type cytokine (IL-4, Il-10, IL-13; P < 0.05) was found in inflammatory cells. In a comparison of the IL-2/IL-4-labeled cell ratio of the four groups, a descending sequence was discovered as NIGO group (0.92 ± 0.97) > H group (0.81 ± 0.61) > P group (0.77 ± 0.82) > S group (0.58 ± 1.77). Conclusions:, Our data support the following: (i) taking nifedipine may elevate the expression of AR in susceptible oral tissue, e.g. gingiva; (ii) the cytokine profile of T-cells in NIGO tissue indicates a trend preferentially towards Th1 activity; and (iii) elevation of AR expression cells and prominent Th1 cytokine-labeled cells are two significant factors in the pathogenesis of NIGO. [source]