Dental caries prevalence and severity positively associate with AMY1 gene copy number.

OBJECTIVE: To establish the possible relation between total caries (TC) and caries severity (CS) with the AMY1 gene copy number (AMY1GCN). MATERIALS AND METHODS: This was an observational, cross-sectional, population-based, and association study with 303 participants. Each participant underwent a complete anamnesis and stomatological check-up, and peripheral blood was obtained to extract gDNA. TC and CS were determined as the number of caries at the dental exploration and the number of dental surfaces affected by caries, respectively, and AMY1GCN was determined by qPCR. RESULTS: We found an elevated caries prevalence (92.7%); TC and CS were 8 ± 10 and 10 ± 13 (median ± IR). There were higher TC and CS in those participants with AMY1GCN above the mean value (0.02 and 0.01 p values, respectively). A positive correlation between TC and CS with AMY1GCN (0.11 and 0.125 r values, 0.03 and 0.01 p values, respectively) was found, in addition to an association between TC and CS with AMY1GCN (1.5 and 1.6 OR values, 0.48 and 0.26 p values, respectively). CONCLUSION: TC and CS were positively related to the AMY1GCN. CLINICAL RELEVANCE: Dental caries has a high prevalence and a multifactorial etiology and has been related to a genetic component. Indeed, the salivary enzyme alpha-amylase could play a significant role in caries susceptibility, considering that its codifying gene (AMY1) can show variation in its gene copy number. This can be considered an important factor for the development of caries at a genetic level.

The Distribution of Eight Antimicrobial Resistance Genes in Streptococcus oralis, Streptococcus sanguinis, and Streptococcus gordonii Strains Isolated from Dental Plaque as Oral Commensals.

It has been proposed that oral commensal bacteria are potential reservoirs of a wide variety of antimicrobial resistance genes (ARGs) and could be the source of pathogenic bacteria; however, there is scarce information regarding this. In this study, three common streptococci of the mitis group (S. oralis, S. sanguinis, and S. gordonii) isolated from dental plaque (DP) were screened to identify if they were frequent reservoirs of specific ARGs (blaTEM, cfxA, tetM, tetW, tetQ, ermA, ermB, and ermC). DP samples were collected from 80 adults; one part of the sample was cultured, and from the other part DNA was obtained for first screening of the three streptococci species and the ARGs of interest. Selected samples were plated and colonies were selected for molecular identification. Thirty identified species were screened for the presence of the ARGs. From those selected, all of the S. sanguinis and S. oralis carried at least three, while only 30% of S. gordonii strains carried three or more. The most prevalent were tetM in 73%, and blaTEM and tetW both in 66.6%. On the other hand, ermA and cfxA were not present. Oral streptococci from the mitis group could be considered frequent reservoirs of specifically tetM, blaTEM, and tetW. In contrast, these three species appear not to be reservoirs of ermA and cfxA.

Bactericidal Activity of Silver Nanoparticles on Oral Biofilms Related to Patients with and without Periodontal Disease.

BACKGROUND AND OBJECTIVES: Periodontal disease (PD) is a multifactorial oral disease regularly caused by bacterial biofilms. Silver nanoparticles (AgNP) have offered good antimicrobial activity; moreover, there is no available scientific information related to their antimicrobial effects in biofilms from patients with PD. This study reports the bactericidal activity of AgNP against oral biofilms related to PD. MATERIALS AND METHODS: AgNP of two average particle sizes were prepared and characterized. Sixty biofilms were collected from patients with (30 subjects) and without PD (30 subjects). Minimal inhibitory concentrations of AgNP were calculated and the distribution of bacterial species was defined by polymerase chain reaction. RESULTS: Well-dispersed sizes of AgNP were obtained (5.4 ± 1.3 and 17.5 ± 3.4 nm) with an adequate electrical stability (-38.2 ± 5.8 and -32.6 ± 5.4 mV, respectively). AgNP showed antimicrobial activities for all oral samples; however, the smaller AgNP had significantly the most increased bactericidal effects (71.7 ± 39.1 µg/mL). The most resistant bacteria were found in biofilms from PD subjects (p < 0.05). P. gingivalis, T. denticola, and T. forsythia were present in all PD biofilms (100%). CONCLUSIONS: The AgNP showed efficient bactericidal properties as an alternative therapy for the control or progression of PD.

Root canal microbiota as an augmented reservoir of antimicrobial resistance genes in type 2 diabetes mellitus patients.

BACKGROUND: Antimicrobial resistance is a global public health problem. Root canal microbiota associated with apical periodontitis represents a well-known reservoir of antimicrobial resistance genes (ARGs). However, the effect of type 2 diabetes mellitus (T2DM) in this reservoir is unknown. This study aimed to establish if root canal microbiota associated with apical periodontitis in T2DM patients is an augmented reservoir by identifying the prevalence of nine common ARGs and comparing it with the prevalence in nondiabetic patients. METHODOLOGY: This cross-sectional study included two groups: A T2DM group conformed of 20 patients with at least ten years of living with T2DM and a control group of 30 nondiabetic participants. Premolar or molar teeth with pulp necrosis and apical periodontitis were included. A sample was collected from each root canal before endodontic treatment. DNA was extracted, and ARGs were identified by polymerase chain reaction. RESULTS: tetW and tetM genes were the most frequent (93.3 and 91.6%, respectively), while ermA was the least frequent (8.3%) in the total population. The distribution of the ARGs was similar in both groups, but a significant difference (p<0.005) was present in ermB, ermC, cfxA, and tetQ genes, being more frequent in the T2DM group. A total of eighty percent of the T2DM patients presented a minimum of four ARGs, while 76.6% of the control group presented a maximum of three. CONCLUSIONS: Root canal microbiota associated with apical periodontitis in T2DM patients carries more ARGs. Therefore, this pathological niche could be considered an augmented reservoir.

A Pilot Feasibility Study to Establish Full Pulpotomy in Mature Permanent Teeth with Symptomatic Irreversible Pulpitis as a Routine Treatment in Mexican Public Healthcare Services.

Symptomatic irreversible pulpitis is a common dental disease for which root canal treatment (RCT) has been the standard treatment. However, in many countries, RCT is considered a high-cost treatment that is not covered by public healthcare services; this forces patients to have dental extraction as their only option to relieve pain. In the last decade, several investigations have provided evidence that an alternative treatment known as full pulpotomy (FP) could be an alternative for patients who could not afford the cost of an RCT. Nevertheless, evidence is lacking on the success rate that could be obtained if it is performed in a public dental care clinic (PDCC). The present investigation has two main objectives. To be the first approach of a multicentric feasibility study to find out whether an FP performed by a general practice dentist (GPD) in a PDCC could be suitable and establish its success rate and patient satisfaction. Patients attending a PDCC with symptoms of irreversible pulpitis were invited to participate. FP was performed and followed up at 1, 3, 6, 9, and 12 months. The treatment success was assessed by combining three variables, patient satisfaction, clinical, and radiographic outcomes. Forty-one patients from 17 to 78 years old received the intervention. In total, 97.5% were completely satisfied with the treatment and were considered successful since none of the clinical or radiographic variables were present in any of the follow-ups. An FP performed by a GPD in a PDCC could be suitable as a routine treatment for symptomatic irreversible pulpitis due to the excellent success rate and patient satisfaction.

Anti-Adherence and Antimicrobial Activities of Silver Nanoparticles against Serotypes C and K of Streptococcus mutans on Orthodontic Appliances.

Background and Objectives: Streptococcus mutans (S. mutans) is the main microorganism associated with the presence of dental caries and specific serotypes of this bacteria have been related to several systemic diseases limiting general health. In orthodontics, white spot lesions (WSL), represent a great challenge for clinicians due to the great fluctuation of their prevalence and incidence during conventional orthodontic treatments. Although silver nanoparticles (AgNP) have been demonstrated to have great antimicrobial properties in several microorganisms, including S. mutans bacteria, there is no available information about anti adherence and antimicrobial properties of AgNP exposed to two of the most relevant serotypes of S. mutans adhered on orthodontic materials used for conventional therapeutics. The objective of this study was to determine anti-adherence and antimicrobial levels of AgNP against serotypes c and k of S. mutans on conventional orthodontic appliances. Materials and Methods: An AgNP solution was prepared and characterized using dispersion light scattering (DLS) and transmission electron microscopy (TEM). Antimicrobial and anti-adherence activities of AgNP were determined using minimal inhibitory concentrations (MIC) and bacterial adherence testing against serotypes c and k of S. mutans clinically isolated and confirmed by PCR assay. Results: The prepared AgNP had spherical shapes with a good size distribution (29.3 ± 0.7 nm) with negative and well-defined electrical charges (−36.5 ± 5.7 mV). AgNP had good bacterial growth (55.7 ± 19.3 µg/mL for serotype c, and 111.4 ± 38.6 µg/mL for serotype k) and adherence inhibitions for all bacterial strains and orthodontic wires (p < 0.05). The serotype k showed statistically the highest microbial adherence (p < 0.05). The SS wires promoted more bacterial adhesion (149.0 ± 253.6 UFC/mL × 104) than CuNiTi (3.3 ± 6.0 UFC/mL × 104) and NiTi (101.1 ± 108.5 UFC/mL × 104) arches. SEM analysis suggests CuNiTi wires demonstrated better topographical conditions for bacterial adherence while AFM evaluation determined cell wall irregularities in bacterial cells exposed to AgNP. Conclusions: This study suggests the widespread use of AgNP as a potential anti-adherent and antimicrobial agent for the prevention of WSL during conventional orthodontic therapies and, collaterally, other systemic diseases.

Root canal microbiota as an augmented reservoir of antimicrobial resistance genes in type 2 diabetes mellitus patients

Abstract Antimicrobial resistance is a global public health problem. Root canal microbiota associated with apical periodontitis represents a well-known reservoir of antimicrobial resistance genes (ARGs). However, the effect of type 2 diabetes mellitus (T2DM) in this reservoir is unknown. This study aimed to establish if root canal microbiota associated with apical periodontitis in T2DM patients is an augmented reservoir by identifying the prevalence of nine common ARGs and comparing it with the prevalence in nondiabetic patients. Methodology This cross-sectional study included two groups: A T2DM group conformed of 20 patients with at least ten years of living with T2DM and a control group of 30 nondiabetic participants. Premolar or molar teeth with pulp necrosis and apical periodontitis were included. A sample was collected from each root canal before endodontic treatment. DNA was extracted, and ARGs were identified by polymerase chain reaction. Results tetW and tetM genes were the most frequent (93.3 and 91.6%, respectively), while ermA was the least frequent (8.3%) in the total population. The distribution of the ARGs was similar in both groups, but a significant difference (p<0.005) was present in ermB, ermC, cfxA, and tetQ genes, being more frequent in the T2DM group. A total of eighty percent of the T2DM patients presented a minimum of four ARGs, while 76.6% of the control group presented a maximum of three. Conclusions Root canal microbiota associated with apical periodontitis in T2DM patients carries more ARGs. Therefore, this pathological niche could be considered an augmented reservoir.

Effect of Streptococcus mutans on surface-topography, microhardness, and mechanical properties of contemporary resin composites.

OBJECTIVE: Dental caries is the most prevalent disease globally, and Streptococcus mutans (S. mutans) is a common associated oral bacteria. Additionally, S. mutans possess esterase activity capable of degrading resin composites (RC). However, the effect of degradation on the physical-mechanical properties of the RC has not been extensively studied. We evaluated the flexure strength (FS), the diametral tensile strength (DTS), the modulus of elasticity (ME), and the microhardness of three contemporary RC to establish if S. mutans could affect them. METHODS: One hundred thirty-eight bar-shaped and 276 disc-shaped specimens were fabricated with Enamel Plus HRi, IPS Empress Direct, and Clearfil AP-X, and physical-mechanical testing was done after been incubated during 30 and 60 days in culture media with or without S. mutans. Also, a scanning electron microscope was used to identify surface changes. RESULTS: None of the tested RC were affected in their mechanical properties (FS, ME, and DTS). However, Clearfil AP-X and Enamel Plus HRI showed eroded surfaces and a decreased microhardness after 30 and 60 days S. mutans incubation. IPS Empress Direct presented the lowest values in all the tests, but its physical-mechanical features and surface were not affected by bacteria's exposure. CONCLUSIONS: Exposure to S. mutans could affect some contemporary RC; however, the effect seems superficial since its mechanical features were not affected.

Antibiotic Resistance Decreases the Efficacy of Endodontic Filling Pastes for Root Canal Treatment in Children's Teeth.

The antibacterial efficacy of antimicrobial filling pastes (AFP) used in the root canal treatment of primary teeth has been widely reported. However, antibiotic resistance as an emerging global problem could impact their current efficacy. This study aimed to evaluate the efficacy of two common AFP on susceptible or resistant bacteria isolated from primary necrotic molars. Microbiological samples were obtained and cultured from the root canals of 34 children. In total, 96 colony-forming units were obtained to determine their resistance to tetracycline, rifampicin, and chloramphenicol. They were identified as S. mutans or E. faecalis using polymerase chain reaction. The antimicrobial activity of CTZ paste (chloramphenicol, tetracycline, zinc oxide, and eugenol) and Guedes-Pinto modified (GPM) paste (rifampicin, prednisolone, iodoform, and camphorated paramonochlorophenol) were tested against the identified and selected microorganisms. Larger size inhibition zones were observed in both species when the tested strains were susceptible to the antibiotics in the AFP preparation. The efficacy of AFP containing antibiotics depends on the antibiotic resistance profile of the strain. Antibiotic resistance and its effect on the AFP were shown, which calls into question the use of simplified endodontic techniques that depend on antibiotics, since in these cases these techniques could not clinically eliminate resistant bacteria from the root canal.

Corrigendum to "In Vitro Determination of Genotoxicity Induced by Brackets Alloys in Cultures of Human Gingival Fibroblasts".

[This corrects the article DOI: 10.1155/2020/1467456.].

Comparison of the retention of conventional dentures after the use of common adhesive brands on poor denture foundations: an in vitro study / Comparación de la retención de dentaduras convencionales con el uso de marcas comerciales de adhesivos en procesos alveolares deficientes: un estudio in vitro

There is no information about the possible impact in denture retention after the use of common denture adhesives (DAs) when poor denture foundations (PDF) are present. Moreover, there is a lack of information about which current formulation provides greater retention and for how long. Twelve models from edentulous patients with different ridge shape and border height were used and complete dentures were manufactured. Four different formulation brands of DAs were tested after 10 minutes and three, six, nine, and 12 hours of DA application using a universal testing machine. The Fittydent® and Fixodent® adhesives had the highest retention at 12 hours. The PDF group increased on average its retention by 400 %. However, the group presented lower retention compared to the good denture foundation group. In conclusion, DAs significantly increased denture retention. The PDF group were the most benefited with the application of DAs. The Fixodent® paste had the highest retention.

No existe información acerca del posible impacto en la retención de dentaduras después del uso de adhesivos dentales comunes (DAs) cuando existen rebordes alveolares deficientes (PDF). Más aun, existe una falta de información acerca de cuál formula actual provee mayor retención y por cuanto tiempo. Doce modelos de pacientes edentulos con diferentes formas y alturas en sus rebordes alveolares fueron usados, y dentaduras completas les fueron realizadas. Cuatro diferentes fórmulas y marcas de DAs fueron evaluadas después de 10 minutos, tres, seis, nueve y 12 horas de que se aplicó el DA usando una maquina universal de pruebas. Los adhesivos Fittydent® y Fixodent® presentaron la retención más alta a las 12 horas. El grupo con PDF incrementó su retención hasta en un 400 %. Sin embargo, el grupo presentó menor retención cuando se comparó con el grupo que posee adecuados procesos alveolares. Los DAs incrementaron significativamente la retención de las dentaduras. El grupo PDF fue el más beneficiado con la aplicación de DAs. La pasta Fixodent® provee la más alta retención.

Dental plaque microbiota of pet owners and their dogs as a shared source and reservoir of antimicrobial resistance genes.

OBJECTIVE: This investigation aimed to detect coincidences in the antimicrobial resistance genes (ARG) profiles between members of a group living in a household and to compare them between other groups in order to establish if an exchange of ARG occurs and if dental plaque microbiota can be considered as a source and reservoir of ARG that can be shared between humans and pets. METHODS: One hundred sixty dental plaque samples were obtained from four groups: Shelter dogs group (n=20), adult pet owners and dogs group (AD group, n=40), adult pet owners, children and dogs group (ACD group, n=60), and adult non-pet owners and children group (AC group, n=40). DNA was obtained, and specific primers with polymerase chain reaction for ARG detection were used. RESULTS: The AD group exhibited the most coincidences in their ARG profiles, 14 (70%) of the 20 profiles coincided in 100% followed by the ACD group with 9 (45%) coincidences. While the AC group was the less coincident group, only 7 (35%) of the 20 profiles coincided. tetM was the most prevalent with 53.1%, followed by tetQ with 52.5% and cfxA with 51.2%, while the less prevalent were tetW with 31.8%, blaTEM-1 with 27.5%, and ermC with 18.7%. CONCLUSION: Dental plaque microbiota can be considered as a source and reservoir of ARG that can be shared between humans and dogs living in a household. The dogs seem to play an important role in the transference of ARG, and the children appear to be the most affected by carrying the most significant number of ARG.

In Vitro Determination of Genotoxicity Induced by Brackets Alloys in Cultures of Human Gingival Fibroblasts.

Orthodontic brackets release ions that can be reabsorbed in the oral mucosa, potentially causing complications, including cytotoxic effects and mutagenic alterations. The aim was to evaluate the genotoxicity induced by orthodontic appliance alloys in cultures of human gingival fibroblasts by comet assay. Eluates were obtained from the following brackets alloys: EconoLine (SS: stainless steel), MiniMirage (Ni-Ti: nickel-titanium), Nu-Edge (Co-Cr: cobalt-chromium), In-Vu (PC-polycrystals (PC) aluminum oxide), and Monocrystal IZE (monocrystalline (MC) aluminum oxide). Each bracket was sterilized and exposed to a corrosive process for 35 days. The obtained eluates were tested for genotoxicity of human gingival fibroblasts (HGFA) by the alkaline comet assay. All study groups showed genotoxic effects; there was a significant difference (p < 0.0001) among groups. The eluates obtained from Ni-Ti showed a 16-times greater genotoxic effect. There were differences in genotoxicity after comparing the Ni-Ti with SS (p < 0.01) and Co-Cr brackets (p < 0.001). The ceramic was more genotoxic than metallic brackets (SS and Co-Cr), but less than the Ni-Ti. This in vitro model will be useful for further study of early DNA damage caused by brackets and other biomaterials used in the oral cavity before their introduction into the clinical setting.

Prevalence of Candida albicans in primary endodontic infections associated with a higher frequency of apical periodontitis in type two diabetes mellitus patients.

To identify the prevalence of C. albicans in primary endodontic infections of type two diabetes mellitus (T2DM) patients and compare their clinical and radiographical characteristics with a non-diabetic control group, establishing the possible relationship between primary endodontic infection, T2DM, and C. albicans, since diabetes mellitus (DM), influences the development, course, and response to the treatment of apical periodontitis, but the presence of Candida albicans (C. albicans) has not been considered before. A total of 120 patients were selected and divided into two groups: 60 T2DM diagnosed patients and 60 non-diabetic controls. A clinical examination and radiographic analysis were performed to establish a periapical index score (PAI). Root canal samples were taken. Deoxyribonucleic acid (DNA) was extracted, and specific primers were used to identify C. albicans by polymerase chain reaction (PCR). A twofold increase in the prevalence of C. albicans in T2DM patients was observed in contrast to control patients (p = 0.0251). Sixty-five percent of T2DM patients with positive C. albicans scored a ≥ 3 PAI, while only 27% of the patients without C. albicans had a ≥ 3 PAI score (p = 0.0065). Long-term DM patients presented C. albicans more frequently (p < 0.0001). In this study, long-term T2DM patients carried C. albicans in their root canals more frequently when having a primary endodontic infection. Furthermore, this C. albicans presence seems to be related to a higher frequency of apical periodontitis.

The frequency and severity of dental caries, and counts of cariogenic bacteria in rheumatoid arthritis patients.

BACKGROUND: It has been reported that patients with rheumatoid arthritis (RA) are more likely to exhibit periodontitis than patients without RA. However, the frequency and severity of dental caries in patients with RA is still unknown. OBJECTIVES: The aim of the study was to investigate whether higher counts of cariogenic bacteria are present in RA patients in contrast to healthy subjects, and to ascertain whether the frequency and severity of dental caries are increased in RA patients. MATERIAL AND METHODS: The study involved 160 adults: an RA group (n = 80) and a control group matched by age and gender (n = 80). The participants' dental status scores were determined based on the following indices: the Decayed, Missing and Filled Teeth (DMFT) index, the Filled and Sound Teeth (FS-T) index, Treatment Needs Index (TNI), Care Index (CI), and Integrative Dental Caries Index (IDCI). DNA copies of Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus) were quantified using realtime polymerase chain reaction (PCR). RESULTS: The IDCI showed that the RA group was more affected, mainly presenting moderate to severe dental caries. The RA group also had higher global DMFT scores than the control group and scored higher on the decayed component of the DMFT index. The TNI and CI indicated that RA patients required more dental attention and appropriate treatment. The Streptococcus mutans count was significantly higher in the RA group. CONCLUSIONS: A complete basic oral examination, along with oral health instruction including adequate oral and dental hygiene, is crucial to prevent dental caries and associated complications in RA patients, since they appear to be more vulnerable than the non-RA population.

Filifactor alocis and Dialister pneumosintes in a Mexican population affected by periodontitis and rheumatoid arthritis: An exploratory study.

Filifactor alocis and Dialister pneumosintes have been associated with the initiation and progression of periodontitis (PE). We determined and compared the frequency of both bacteria in patients with PE, rheumatoid arthritis (RA), and PE/RA simultaneously. Detection was performed by polymerase chain reaction in the subgingival biofilm. Bacteria were more frequent in patients with PE, and clinical periodontal parameters such as pocket depth (PD) and clinical attachment loss (CAL) were significantly higher in patients with PE/RA. F. alocis and D. pneumosintes could influence PD and CAL, hence participating in the initiation and progression of PE in patients with RA.

Detection of the antimicrobial resistance genes blaTEM-1, cfxA, tetQ, tetM, tetW and ermC in endodontic infections of a Mexican population.

OBJECTIVES: The aim of this study was to identify the prevalence of genes encoding resistance to three groups of antimicrobial agents in root canal samples from primary infection or post-treatment disease in Mexico. METHODS: A total of 64 subjects requiring root canal treatment because of primary infection or post-treatment disease were enrolled in this cross-sectional analytical study. Root canal samples were obtained and DNA was isolated. Specific primers for six antimicrobial resistance genes (ARGs) and seven bacterial taxa (five genera and two species) were used. Student's t-test, χ2 test and Fisher's exact test were applied where appropriate to detect statistical differences. RESULTS: The blaTEM-1, ermC and tetM genes were found more frequently in the post-treatment disease group compared with the primary infection group. The occurrence of assessed bacteria was similar in both groups, except for Enterococcus spp. and Porphyromonas endodontalis, which were found at a significantly higher frequency in the post-treatment disease group. It was observed that the post-treatment disease group harboured more ARGs. The most frequent ARG was tetW, whereas tetQ and cfxA were not detected in any case. With respect to bacterial taxa, Fusobacterium spp. was present in 100% of samples, whereas Porphyromonas gingivalis was not observed in any of the samples. CONCLUSIONS: At least one ARG was detected in all cases; moreover, 32.8% of samples were positive for four ARGs, 54.7% for three ARGs, 9.4% for two ARGs and only 3.1% for one ARG. This indicates a high prevalence and diversity of ARGs in these root canal samples.

Periapical Healing of Endodontically Treated Teeth Filled Only in the Apical Third: A Randomized Controlled Trial.

OBJECTIVE: To provide evidence from a clinical viewpoint that the bacteria persisting within the root canal system do not have a significant impact on the treatment outcome as long as an adequate apical sealing is performed. METHODS: A total of 42 patients with pulp necrosis and a periapical index (PAI) score of 5. Root canal treatment was performed in which the root canal filling was limited to the apical third of the root. In the control group, the root canal filling was performed up to the canal orifice. Data were analyzed using the Mann-Whitney test and the χ2 or the Fisher exact test (when appropriate). RESULTS: All cases presented clinical success, absence of pain, swelling, sinus tract, tenderness to palpation or percussion and presented normal tooth mobility. Fifteen months were enough for all cases of both groups to be classified with a PAI score of ≤2. There was no statistical difference between the cases that ended the study with a PAI-1 or PAI-2 score. CONCLUSION: Within the limitations of this study, no significant differences in healing rates after complete obturation or only apical third obturation were observed. An adequate apical sealing can improve periapi-cal healing, thus intracanal remnant bacteria apparently have no significant impact, at least for the first 15 months of follow-up.

Association of cytokines polymorphisms with chronic peridontitis and rheumatoid arthritis in a Mexican population.

OBJECTIVE: Historically, it has been shown that rheumatoid arthritis (RA) and periodontitis (PE) share pathophysiological similarities and possibly a genetic background. In order to elucidate the genetic background between both diseases, we evaluated the distributions of five SNPs genotypes and all the possible haplotypes composed in subjects with isolated RA, PE, combined diseases and healthy controls. MATERIALS AND METHODS: The study population consisted of 280 Mexican subjects. Genomic DNA was isolated from buccal epithelial cells collected by cheek scrapings and analyzed for the determination of the following SNPs: IL-1α + 4845 (rs17561), IL-1α -889 (rs1800587), IL-1ß + 3954 (rs1143634), IL-1ß -511(rs16944) and TNF-α -308 (rs1800629). RESULTS: After adjustment for age, sex and smoking status, multiple logistic regression analysis revealed a no significant association in the genotype frequencies of TNF-α -308 and IL-1α + 4845 SNPs. Otherwise a significant association was observed in IL-1ß + 3954 and IL-1ß -511 (p < 0.05) while IL-1α -889 was of borderline statistical significance (p = 0.054). Also, we found three negative associated haplotypes with PE: IL-1α + 4845 G/IL-1ß -511 A, IL-1ß + 3954 C/IL-1ß -511 A and interestingly IL-1α -889 C/IL-1ß -511 A also with a positive association with RA. CONCLUSIONS: Some genotypes and haplotypes are associated with the diseases. But it seems that the genetic background of the association between RA and PE needs to be explored deeper.

Association between periodontitis, periodontopathogens and preterm birth: is it real?

PURPOSE: To identify the association between periodontitis and periodontal pathogens with preterm birth despite the strict control of some important confounders, such as infectious processes and criteria for diagnosis of periodontitis during pregnancy. MATERIALS AND METHODS: In this cross-sectional study were included 70 healthy puerperal women between 20 and 35 years without a history of genitourinary infections during pregnancy. Based on the gestational age they were divided into two groups: 45 with term birth (>37 weeks) and 25 with preterm birth (<37 weeks). Previous informed consent, a gynecologic and dental history that included gynecologic and obstetric background, periodontal status applying different authors' criteria of periodontitis diagnosis, presence of periodontopathogens, dental caries and oral hygiene were recorded. RESULTS: There was no association between periodontitis, periodontopathogens and preterm birth. There were no statistical differences applying different authors' criteria diagnosis of periodontitis. Gingivitis status was similar, but probing depth was greater in preterm birth subjects, perhaps they are young women, and this finding could be an early sign of periodontitis. In like manner, the main periodontal bacterial species are not associated with preterm birth, general hygiene and care habits are poorer than term birth subjects. CONCLUSION: We could suggest that preterm birth is a multifactorial condition and the role of periodontitis and the periodontopathogens itself is not sufficient to trigger the preterm birth. There are factors such as infectious processes and diagnostic criteria for periodontitis that could be responsible for controversial results.