A bacterial tyrosine phosphatase modulates cell proliferation through targeting RGCC.

Tyrosine phosphatases are often weaponized by bacteria colonizing mucosal barriers to manipulate host cell signal transduction pathways. Porphyromonas gingivalis is a periodontal pathogen and emerging oncopathogen which interferes with gingival epithelial cell proliferation and migration, and induces a partial epithelial mesenchymal transition. P. gingivalis produces two tyrosine phosphatases, and we show here that the low molecular weight tyrosine phosphatase, Ltp1, is secreted within gingival epithelial cells and translocates to the nucleus. An ltp1 mutant of P. gingivalis showed a diminished ability to induce epithelial cell migration and proliferation. Ltp1 was also required for the transcriptional upregulation of Regulator of Growth and Cell Cycle (RGCC), one of the most differentially expressed genes in epithelial cells resulting from P. gingivalis infection. A phosphoarray and siRNA showed that P. gingivalis controlled RGCC expression through Akt, which was activated by phosphorylation on S473. Akt activation is opposed by PTEN, and P. gingivalis decreased the amount of PTEN in epithelial cells. Ectopically expressed Ltp1 bound to PTEN, and reduced phosphorylation of PTEN at Y336 which controls proteasomal degradation. Ltp-1 induced loss of PTEN stability was prevented by chemical inhibition of the proteasome. Knockdown of RGCC suppressed upregulation of Zeb2 and mesenchymal markers by P. gingivalis. RGCC inhibition was also accompanied by a reduction in production of the proinflammatory cytokine IL-6 in response to P. gingivalis. Elevated IL-6 levels can contribute to periodontal destruction, and the ltp1 mutant of P. gingivalis incited less bone loss compared to the parental strain in a murine model of periodontal disease. These results show that P. gingivalis can deliver Ltp1 within gingival epithelial cells, and establish PTEN as the target for Ltp1 phosphatase activity. Disruption of the Akt1/RGCC signaling axis by Ltp1 facilitates P. gingivalis-induced increases in epithelial cell migration, proliferation, EMT and inflammatory cytokine production.

The subgingival microbiome associated with periodontitis in type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is a systemic disease, predisposing patients to other inflammatory conditions including periodontitis. The subgingival microbiome, a key player in periodontitis pathogenesis, is not well characterized in T2DM population. To better understand whether the subgingival microbiome is different between T2DM and systemically healthy, nondiabetic (ND) subjects, we performed a longitudinal analysis of the subgingival microbiome in T2DM patients (n = 15) compared with ND subjects (n = 16). Using metagenomic shotgun sequencing, we investigated the microbiome in the healthy periodontal state, periodontitis state, and resolved state after treatment. We found that in the periodontitis state, the shift in the subgingival microbiome from the healthy state was less prominent in T2DM compared with ND subjects, yet the clinical signs of disease were similar for both. Furthermore, we revealed highly correlated presence of pathogenic species in relative abundance not only in the periodontitis state, but also in the healthy state in T2DM, suggesting an elevated risk of progression to periodontitis in this cohort. We further investigated the functional potentials of the subgingival microbiome and identified a set of microbial marker genes associated with the clinical states. These genes were significantly enriched in 21 pathways, some of which are associated with periodontitis and some potentially link T2DM and periodontitis. This study identified the longitudinal changes of the subgingival microbiome associated with periodontitis in T2DM and suggests that T2DM patients are more susceptible to shifts in the subgingival microbiome toward dysbiosis, potentially due to impaired host metabolic and immune regulation.

Subgingival Microbiota of Mexicans with Type 2 Diabetes with Different Periodontal and Metabolic Conditions.

BACKGROUND: Type-2-Diabetes (T2D) and Periodontitis are major inflammatory diseases. However, not much is known about the specific subgingival microbiota in Mexicans with diabetes and metabolic dysbiosis. The aim of this study was to describe the subgingival microbiota of Mexicans with T2D and the different periodontal and metabolic conditions, through "Checkerboard" DNA-DNA hybridization. METHODS: Subjects were divided into two groups-periodontal-health (PH) (PH_non-T2D; n = 59, PH_T2D; n = 14) and generalized-periodontitis (GP) (GP_non-T2D; n = 67, GP_T2D; n = 38). Obesity (BMI ≥ 30 kg/m2) and serum levels of glycated-hemoglobin (HbA1c), total-lipids, triglycerides, total-cholesterol, high-density-lipids, and low-density-lipids were measured for the T2D individuals. Subgingival microbial identification was processed for 40 species through DNA-probes. RESULTS: Subjects with T2D harbored significantly higher mean total levels (PH: p < 0.001, and GP_NS), a lower proportion of "red" complex (GP: p < 0.01), a higher proportion of "yellow" (GP; p < 0.001), and "orange" (GP; p < 0.01) complex than the non-T2D. GP_T2D individuals exhibited a greater proportion of putative-species-Campylobacter gracilis and S. constellatus (p < 0.001), and Parvimonas micra and Prevotella nigrescens (p < 0.01), than GP_non-T2D. T2D individuals with HbA1c > 8% had presented significantly higher mean pocket-depth and higher levels of G. morbillorum (p < 0.05) and those with obesity or dyslipidemia harbored higher levels, prevalence, or proportion of Streptococcus sp., Actinomyces sp., and Capnocytophaga sp. CONCLUSIONS: T2D individuals harbored a particular microbial profile different to non-T2D microbiota. Metabolic control was related to dysbiosis of microbiota-HbA1c>8% related to periodontitis and obesity or dyslipidemia with the predominance of saccharolytic bacteria, irrespective of their periodontal condition.

The use of antimicrobial photodynamic therapy in oral injuries of a pediatric patient with myelodysplastic syndrome: case report.

AIM: To report a case of a pediatric patient carrier of myelodysplastic syndrome (MDS) with severe oral infectious disease, in which antimicrobial photodynamic therapy (aPDT) was used as a therapeutic choice to support systemic treatment. METHODS AND RESULTS: This case report refers to a 1-year-old male patient with MDS and hospitalized for investigation and treatment of complications at a Pediatric Oncology and Hematology Center in Recife/PE, Brazil. The intraoral examination revealed a violaceous lesion surrounding the lower incisor teeth, which progressed with alteration of color to milky yellowish white, compromising the entire lower gingival border, leading to tooth mobility and consequent loss of teeth 71 and 81. The patient was treated under systemic antimicrobial therapy and aPDT was also performed, using a photosensitizing agent (methylene blue, 0.01%) and a low-intensity laser in the visible red spectrum. Oral clinical improvement was observed, but the patient died after 45 days of hospitalization in the Pediatric ICU due to other systemic complications. CONCLUSION: MDS may present limiting oral repercussions interfering in patients' quality of life. The aPDT is presented as an adjuvant therapeutic modality in oral infections with satisfactory results.

Chronic paracoccidioidmycosis in a woman with Crohn Disease.

We report a rare case of chronic paracoccidioidomycosis(PCM) in a woman with Crohn disease in the setting of treatment with azathioprine and mesalazine. Serum tests for antigens to Paracoccidioides brasiliensis, Histoplasma capsulatum, and Aspergillus fumigatus were negative. An incisional biopsy of an oral lesion with periodic acid-schiff and Grocott-methenamine silver stains revealed chronic granulomatous inflammation with multinucleated giant cells with Paracoccidioides brasiliensis within the cytoplasm, confirming the diagnosis of PCM.

Assessment of Photodynamic Inactivation against Periodontal Bacteria Mediated by a Chitosan Hydrogel in a 3D Gingival Model.

Chitosan hydrogels containing hydroxypropyl methylcellulose (HPMC) and toluidine blue O were prepared and assessed for their mucoadhesive property and antimicrobial efficacy of photodynamic inactivation (PDI). Increased HPMC content in the hydrogels resulted in increased mucoadhesiveness. Furthermore, we developed a simple In Vitro 3D gingival model resembling the oral periodontal pocket to culture the biofilms of Staphylococcus aureus (S. aureus), Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), and Porphyromonas gingivalis (P. gingivalis). The PDI efficacy of chitosan hydrogel was examined against periodontal biofilms cultured in this 3D gingival model. We found that the PDI effectiveness was limited due to leaving some of the innermost bacteria alive at the non-illuminated site. Using this 3D gingival model, we further optimized PDI procedures with various adjustments of light energy and irradiation sites. The PDI efficacy of the chitosan hydrogel against periodontal biofilms can significantly improve via four sides of irradiation. In conclusion, this study not only showed the clinical applicability of this chitosan hydrogel but also the importance of the light irradiation pattern in performing PDI for periodontal disease.

A Double-Blind Randomized Trial Comparing Implants with Laser-Microtextured and Machined Collar Surfaces: Microbiologic and Clinical Results.

PURPOSE: The purpose of this study was to compare the clinical outcome of and determine the differences in periodonto-pathogenic microbiota around two types of implant collar surfaces: laser-microtextured (test) vs machined (control). MATERIALS AND METHODS: Seventeen patients (11 periodontally healthy, and 6 periodontally compromised) were selected to receive the two different implants, placed randomly, in two edentulous sites. Six months following the surgical placement of the dental implants, subgingival plaque samples were collected using paper points from the peri-implant sulcus and from the sulcus of an adjacent tooth. The presence of five putative periodontal pathogens, namely, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, and Tannerella forsythensis, was assessed using real-time polymerized chain reaction (RT-PCR). Peri-implant parameters and intraoral radiographs were recorded up to 1 year after abutment connection. RESULTS: In the main population, and in the periodontally compromised subgroup, the total number of periodontal pathogens around test implant sites was lower than control implant sites and adjacent tooth sites, with a statistically significant difference (P < .05). In periodontally healthy patients, the mean probing pocket depth for the test implant was 1.31 ± 0.51 mm, compared with 2.66 ± 0.83 mm for the control implant, while in periodontally compromised patients, it was 1.61 ± 0.58 mm for the test implant, compared with a mean value of 2.84 ± 1.0 mm for the control implant. CONCLUSION: Implants with a laser-microtextured collar surface are not more vulnerable to pathogenic microflora colonization than implants with a machined collar surface. In both of the subgroups of patients (periodontally healthy and periodontally compromised), implants with a laser-microtextured collar surface have a better clinical outcome at 1 year of loading, compared with implants with a machined collar surface.

Oral ulcer by Sphingomonas paucimobilis: first report.

The first case of an oral infection caused by Sphingomonas paucimobilis is reported. A 73-year-old man presented with a gingival ulcer with bone exposure affecting the attached gingiva in the anterior maxillary region. He reported pain during chewing and the presence of fever. Since the first case of S. paucimobilis infection was reported in 1977, involving a leg ulcer, the number of reports related to this organism has been increasing, indicating that the bacterium should be considered an emerging pathogen. It is possible that other non-classical pathogens of the oral cavity may be responsible for infectious lesions, which represents a diagnostic and therapeutic challenge.

Microbial dynamics during conversion from supragingival to subgingival biofilms in an in vitro model.

The development of dental caries and periodontal diseases result from distinct shifts in the microbiota of the tooth-associated biofilm. This in vitro study aimed to investigate changes in biofilm composition and structure, during the shift from a 'supragingival' aerobic profile to a 'subgingival' anaerobic profile. Biofilms consisting of Actinomyces oris, Candida albicans, Fusobacterium nucleatum, Streptococcus oralis, Streptococcus mutans and Veillonella dispar were aerobically grown in saliva-containing medium on hydroxyapatite disks. After 64 h, Campylobacter rectus, Prevotella intermedia and Streptococcus anginosus were further added along with human serum, while culture conditions were shifted to microaerophilic. After 96 h, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola were finally added and the biofilm was grown anaerobically for another 64 h. At the end of each phase, biofilms were harvested for species-specific quantification and localization. Apart from C. albicans, all other species gradually increased during aerobic and microaerophilic conditions, but remained steady during anaerobic conditions. Biofilm thickness was doubled during the microaerophilic phase, but remained steady throughout the anaerobic phase. Extracellular polysaccharide presence was gradually reduced throughout the growth period. Biofilm viability was reduced during the microaerophilic conversion, but was recovered during the anaerobic phase. This in vitro study has characterized the dynamic structural shifts occurring in an oral biofilm model during the switch from aerobic to anaerobic conditions, potentially modeling the conversion of supragingival to subgingival biofilms. Within the limitations of this experimental model, the findings may provide novel insights into the ecology of oral biofilms.

Primary Gingival Tuberculosis Diagnosed Based on Genetic Identification.

A case of primary gingival tuberculosis in a 71-year-old Japanese woman is herein presented. A serous saliva culture was positive for tuberculosis, and we recognized that the origin of the tuberculosis infection was the gingiva based on the genetic identification in gingival biopsy tissue. The definitive diagnosis was facilitated by the genetic identification, a useful modern tool for diagnosing infectious diseases. The location and clinical presentation of this lesion were unusual, which underlines the importance of considering tuberculosis in the differential diagnosis of oral lesions that affect the gingiva.

Alterations of the Subgingival Microbiota in Pediatric Crohn's Disease Studied Longitudinally in Discovery and Validation Cohorts.

BACKGROUND: Oral manifestations are common in Crohn's disease (CD). Here we characterized the subgingival microbiota in pediatric patients with CD initiating therapy and after 8 weeks to identify microbial community features associated with CD and therapy. METHODS: Pediatric patients with CD were recruited from The Children's Hospital of Pennsylvania. Healthy control subjects were recruited from primary care or orthopedics clinic. Subgingival plaque samples were collected at initiation of therapy and after 8 weeks. Treatment exposures included 5-ASAs, immunomodulators, steroids, and infliximab. The microbiota was characterized by 16S rRNA gene sequencing. The study was repeated in separate discovery (35 CD, 43 healthy) and validation cohorts (43 CD, 31 healthy). RESULTS: Most subjects in both cohorts demonstrated clinical response after 8 weeks of therapy (discovery cohort 88%, validation cohort 79%). At week 0, both antibiotic exposure and disease state were associated with differences in bacterial community composition. Seventeen genera were identified in the discovery cohort as candidate biomarkers, of which 11 were confirmed in the validation cohort. Capnocytophaga, Rothia, and TM7 were more abundant in CD relative to healthy controls. Other bacteria were reduced in abundance with antibiotic exposure among CD subjects. CD-associated genera were not enriched compared with healthy controls after 8 weeks of therapy. CONCLUSIONS: Subgingival microbial community structure differed with CD and antibiotic use. Results in the discovery cohort were replicated in a separate validation cohort. Several potentially pathogenic bacterial lineages were associated with CD but were not diminished in abundance by antibiotic treatment, suggesting targets for additional surveillance.

Extensive Inflammatory Gingival Tumor in a Young Nonsmoking Woman: Back to Basics.

Tuberculous lesions of the oral cavity are rare and can be a diagnostic challenge, particularly in young immunocompetent patients. Most of the cases in the literature are secondary to pulmonary disease, whereas primary form is uncommon. This paper presents a case of gingival tuberculosis in a 26-year-old Indian female patient, manifesting as a rapidly extensive ulcer. The diagnosis was confirmed by histopathology and immunological investigations. Although oral manifestations of tuberculosis are rare, clinicians should include them in the differential diagnosis of various types of oral ulcers. An early diagnosis with a prompt treatment can prevent complications and potential contaminations.

Fusobacterium nucleatum Alters Atherosclerosis Risk Factors and Enhances Inflammatory Markers with an Atheroprotective Immune Response in ApoE(null) Mice.

The American Heart Association supports an association between periodontal disease (PD) and atherosclerotic vascular disease (ASVD) but does not as of yet support a causal relationship. Recently, we have shown that major periodontal pathogens Porphyromonas gingivalis and Treponema denticola are causally associated with acceleration of aortic atherosclerosis in ApoEnull hyperlipidemic mice. The aim of this study was to determine if oral infection with another significant periodontal pathogen Fusobacterium nucleatum can accelerate aortic inflammation and atherosclerosis in the aortic artery of ApoEnull mice. ApoEnull mice (n = 23) were orally infected with F. nucleatum ATCC 49256 and euthanized at 12 and 24 weeks. Periodontal disease assessments including F. nucleatum oral colonization, gingival inflammation, immune response, intrabony defects, and alveolar bone resorption were evaluated. Systemic organs were evaluated for infection, aortic sections were examined for atherosclerosis, and inflammatory markers were measured. Chronic oral infection established F. nucleatum colonization in the oral cavity, induced significant humoral IgG (P=0.0001) and IgM (P=0.001) antibody response (12 and 24 weeks), and resulted in significant (P=0.0001) alveolar bone resorption and intrabony defects. F. nucleatum genomic DNA was detected in systemic organs (heart, aorta, liver, kidney, lung) indicating bacteremia. Aortic atherosclerotic plaque area was measured and showed a local inflammatory infiltrate revealed the presence of F4/80+ macrophages and CD3+ T cells. Vascular inflammation was detected by enhanced systemic cytokines (CD30L, IL-4, IL-12), oxidized LDL and serum amyloid A, as well as altered serum lipid profile (cholesterol, triglycerides, chylomicrons, VLDL, LDL, HDL), in infected mice and altered aortic gene expression in infected mice. Despite evidence for systemic infection in several organs and modulation of known atherosclerosis risk factors, aortic atherosclerotic lesions were significantly reduced after F. nucleatum infection suggesting a potential protective function for this member of the oral microbiota.

Invasión fúngica en tejido conectivo en pacientes con enfermedad gingivo-periodontal / Fungal invasion of connective tissue in patients with gingival-periodontal disease

Antecedentes. En los últimos años se ha descrito la presencia de microorganismos inusuales en el biofilm subgingival, posibles iniciadores o contribuyentes a la patogenia de la enfermedad periodontal, particularmente en personas que responden mal a la terapia. Objetivos. Estudiar la invasión de levaduras del género Candida en el tejido conectivo gingival, y su relación con la portación en el biofilm subgingival. Métodos. Se estudiaron 55 pacientes de ambos sexos, entre 21 y 55 años, con enfermedades gingivo-periodontales, inmunocompetentes, no fumadores y sin tratamiento antimicrobiano previo. Se tomaron muestras de tejidos blandos, de placa supragingival y subgingival, y biopsias de las bolsas periodontales. Se llevaron a cabo estudios microscópicos, cultivos, perfiles de asimilación y amplificación de ADN. Resultados. En los cultivos realizados, el 35% de las muestras presentaban diferentes especies de Candida, con mayor prevalencia de Candida albicans. Se evidenció la presencia de hifas invadiendo el tejido conectivo en asociación con microorganismos anaerobios (Porphyromonas gingivalis, Prevotella intermedia y Aggregatibacter actinomycetemcomitans) en los pacientes con periodontitis. Conclusiones. Las distintas especies de Candida podrían formar parte de la placa microbiana periodontal y jugar un papel fundamental en la adherencia de la misma a los tejidos, permitiendo la invasión en profundidad. Así también podrían infectar las bolsas de los pacientes con gingivitis, incluso en sitios sanos, cumpliendo un papel de comensal u oportunista (AU)

Background. In the last few years unusual microorganisms have been isolated from subgingival biofilm, as possible initiators or contributors to periodontal disease, especially in patients who show no improvement during treatment. Aims. To study the Candida invasion of the connective tissue in relation to subgingival biofilm presence. Methods. A total of 55 immunocompetent patients of both sexes, between 21 and 55 years of age, non-smokers, without previous antimicrobial treatment, suffering periodontal diseases, were studied. Soft tissues, supragingival and subgingival plaque samples, and periodontal pocket biopsies were taken. Microscopic studies, cultures, assimilation profiles, and DNA amplifications were performed. Results. In 35% of the samples, different species of Candida were isolated in cultures, especially Candida albicans. Hyphae invasions in the connective tissue were observed, in association with anaerobic microorganisms (Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans) in patients with periodontitis. Conclusions. Different species of Candida could be part of the periodontal plaque and could play an important role in the adherence to soft tissues, allowing deep invasion. They also could infect gingival pockets in patients with gingivitis, even in healthy locations, playing a commensal or opportunist role (AU)

Gingival response in orthodontic patients: comparative study between self-ligating and conventional brackets

Orthodontic brackets contribute to the accumulation of bacterialplaque on tooth surfaces because they hinder oral hygiene.In contrast to conventional brackets, self-ligating brackets donot require additional parts to support the arches, thus improvingdental hygiene. The aim of this study was to compare thegingival response in orthodontic patients wearing self-ligatingor conventional brackets. A sample of 22 patients aged 16 to 30years was divided into two groups: Group A, treated with selfligatingbrackets (Damon system) and Group B, treated withconventional brackets (Roth technique). The following wereassessed during the treatment: Plaque Index (PI), GingivalIndex (GI) and Probing Depth (PD), and sub-gingival sampleswere taken from teeth 14/24 for microbiological observation.No statistically significant difference was found between GroupsA and B; p>0.05 (sign-ranked) or between PI, GI and PD at thedifferent times (Friedman’s Analysis of Variance), even thoughthe indices were found to increase at 14 days, particularly forself-ligating brackets. The quantity and quality of microorganismspresent were compatible with health on days 0, 28 and 56.As from day 14 there is a predominance of microbiota compatiblewith gingivitis in both groups. In the samples studied,orthodontic treatment increases bacterial plaque and inflammatorygingival response, but gingival-periodontal health canbe maintained with adequate basic therapy...

bacteriana en las superficies dentarias, debido a que dificultanla higiene oral. A diferencia de los brackets convencionales, losbrackets autoligables no requieren elementos adicionales parasujetar los arcos, lo cual favorecería la higiene dentaria. Elobjetivo del presente trabajo fue comparar la respuesta gingivalen pacientes ortodóncicos, utilizando brackets autoligablesy brackets convencionales. Se estudiaron 22 pacientes, entre 16y 30 años, divididos en dos grupos: A, tratado con bracketsautoligables, Sistema Damon) y B, tratado con brackets convencionales,Técnica de Roth. Durante el tratamiento, seevaluaron los Índices de Placa (IP), Índice Gingival (IG) y Profundidadde Sondaje (PS) y se tomaron muestras subgingivalesde las piezas 14/24 para su observación microbiológica. En laevaluación estadística no se encontraron diferencias estadísticamentesignificativa entre los grupos A y B; p>0.05 (de losrangos con signo) y ni en los IP, IG y PS en los diferentes tiemposevaluados (Análisis de varianza de Friedman), sin embargose observa un aumento en los índices a los 14 días, sobre todoen autoligables. Los microorganismos se presentaron en cantidady calidad compatible con salud el día 0, 28 y 56; a partirdel día 14 predomina microbiota compatible con gingivitis paraambos grupos. En las muestras estudiadas el tratamientoortodóncicos produce incremento de placa bacteriana yrespuesta gingival inflamatoria, pero con terapia básica adecuadapuede mantenerse la salud gingivo-lperiodontal. Losbrackets autoligables y los o convencionales, produjeronrespuesta gingival simila...

Primary gingival tuberculosis diagnosis: a difficult endeavor.

AIM: To highlight the importance of considering tuberculosis in the differential diagnosis even in the absence of confirmation from several investigations and diagnostic aides. BACKGROUND: Tuberculosis is a common infectious granulomatous disease caused by various strains of mycobacteria. An oral lesion when seen in association with tuberculosis is very rare and in most cases is noticed secondary to pulmonary forms. CASE REPORT: We report a case of primary gingival tuberculosis in 20-year-old female patient who presented with treatment resistant gingivitis. Patient had no evidence of disease elsewhere in the body and several diagnostic tests also failed to reveal the presence of the causative organism. Resolution of gingivitis was noted following a therapeutic trial of antitubercular drugs. CONCLUSION: Therefore the importance of including tuberculosis in the differential diagnosis of inflammatory disorder of the gingiva is very essential in order to avoid one of the most lethal forms of infections often overlooked. CLINICAL SIGNIFICANCE: It is essential to consider tuberculosis as one of the differential diagnosis in India even when several diagnostic tests are negative for tuberculosis.

Arteriovenous malformation (AVM) of the maxilla complicated by a local pathogen infection.

Arteriovenous malformations (AVM) are usually observed on the skin, but they can also rarely affect the visceral organs and the maxillofacial area. In the maxillofacial area, these lesions can spread and they are potentially dangerous, as a biopsy or even a simple tooth extraction can lead to a catastrophic haemorrhage that may eventually cause death. There are several indications for the treatment, including age, size and type of vascular malformation. The purpose of this report is to describe an AVM on the maxilla, first diagnosed as an epulis, which has been treated for several years as a chronic local periodontitis. The lesion was finally stabilised after an antibiotic therapy. Improved knowledge of the development of these lesions and collaboration between dentists, radiologists and surgeons are necessary to improve the diagnosis and treatment of vascular malformations.

Retrospective investigation of gingival invaginations: Part II: microbiological findings and genetic risk profile.

BACKGROUND AND OBJECTIVE: Gingival invaginations are a frequent finding during tooth extraction and following orthodontic space closure. Based on the interdental localization and sometimes pronounced depth, it has been suggested that a gingival invagination may impede oral hygiene. In Part I of this series, the time until active tooth movement and the localization of extraction were identified as potential risk factors for the development of gingival invagination. The aims of the present study were the analysis of the microbial spectrum of a gingival invagination in comparison with pool samples of the sulcus of Ramfjord teeth, on the one hand, and the importance of genetic variations of the pro-inflammatory mediator interleukin-1 (IL-1) and its receptor antagonist (IL-1-RN), on the other hand. In addition, a possible role of smoking as a risk factor was evaluated. SUBJECTS AND METHODS: A total of 30 patients with (n=16) and without (n=14) gingival invagination were examined for the presence of eleven periodontal pathogen bacterial species with a commercially available test (micro-IDent®Plus, Hain Lifescience, Nehren, Germany). The genetic evaluation was performed with the GenoType® IL-1 test (Hain Lifescience). RESULTS: The results of the microbiological analysis of gingival invaginations showed that the bacterial flora might differ or even be higher than the pool sample from sulcus regions. The genetic evaluation demonstrated that in the group without gingival invagination only 14% showed an IL-1 polymorphism, whereas this value was twice as high (35%) in the group with gingival invagination. In addition, a combination of both polymorphisms IL-1 and IL-1-RN was only found in patients with gingival invagination (25%). Interestingly, smoking patients showed a significant increase of the severity of the gingival invagination. CONCLUSION: This retrospective study demonstrated that gingival invagination might be accompanied with an altered microbiological bacterial spectrum and a genetic IL-1 polymorphism. In addition, smoking was identified as another potential risk factor for the severity of gingival invaginations.