Clinical evaluation of nanofill and nanohybrid composite in Class I restorations: a 12-month randomized trial.

This randomized trial evaluated the 12-month clinical performance of nanofill, a nanohybrid, and a microhybrid composite in restorations in occlusal cavities of posterior teeth. This study utilized 41 patients, each of whom had three molars affected by primary caries or the need to replace restorations. All restorations were performed in accordance with the manufacturer's recommendations and evaluated in accordance with U.S. Public Health Service-modified criteria. Based on the results of the present study, the material investigated demonstrated acceptable clinical performance after 12 months of clinical service. Long-term re-evaluations are necessary for a more detailed analysis of these composites.

Efficacy of composites filled with nanoparticles in permanent molars: Six-month results.

This study sought to evaluate the clinical performance of composites filled with nanoparticles six months after placement in the occlusal surface of molars with Class I cavities. This study involved 41 patients, each of whom had three molars affected by primary caries or the need to replace restorations. All restorations were performed in accordance with the manufacturer's recommendations and evaluated in accordance with USPHS modified criteria. Based on the results of the present study, composites reinforced with nanoparticles can be used in posterior teeth, although their performance was not superior to that of the microhybrid composite. Long-term re-evaluations are necessary for a more detailed analysis of these composites.

Clinical and microbiological characteristics in predicting dentine caries progression.

The purpose of this study was to evaluate the clinical aspect of dentine and its microbiota in predicting caries progression. The sample consisted of schoolchildren in the 7 to 14 years age group. Treatment involved cavity preparation trough the clinical criterion of hardness, with the collection of carious and remnants dentine for microbiological analysis. The clinical aspect (color and consistency) of the dentine remmants was recorded and the teeth were restored using silver amalgam and glass ionomer cement as pulpal protector (baseline - BL). After 1 year the restoration was removed and after new clinical and microbiological analyses, the teeth were then restored. Microbiological samples were collected at both time-points and cultivated in sheep blood agar, in anaerobiosis for 48 hours. Bacterial growth was analyzed quantitatively. Semiquantitative and qualitative analysis of the bacteria was performed by hybridization with genomic DNA probes and the checkerboard method. A significant difference was observed between the aspect of dentine remnants at BL and at 1 year (p=0.0078). The amount of bacteria at BL and at 1 year did not differ significantly (p= 0.37) and the microbiota of the carious dentine was predominantly composed of Gram-positive cocci. The removal of carious dentine based on the clinical criterion of hardness, followed by a well-adapted restoration, would determine the non-progression of caries. The few bacteria that still remained in the cavity would be no longer viable.

Presence and associated factors of carotid artery calcification detected by digital panoramic radiography in patients with chronic kidney disease undergoing hemodialysis.

OBJECTIVES: The aim of this study was to investigate the presence and associated factors of carotid artery calcification (CAC) in patients with chronic kidney disease (CKD) undergoing hemodialysis. STUDY DESIGN: A total of 309 panoramic radiographs of patients with CKD (180 men and 129 women; mean age 43.7 years) undergoing hemodialysis were evaluated by a single radiologist to determine the frequency of CAC. An analysis of associated factors, such as age, sex, time spent in hemodialysis, arterial hypertension, diabetes mellitus, biochemical parameters, and other systemic diseases, was also performed. RESULTS: The presence of CAC in patients with CKD, as determined on the basis of panoramic radiography, was 15.9%. The χ2 test revealed that there was a statistically significant association between certain factors, such as age, sex, and diabetes mellitus, and the presence of CAC (P < .05). Multivariate analysis demonstrated that time spent in hemodialysis was significantly associated with the occurrence of CAC. CONCLUSIONS: A significant presence of CAC was detected on digital panoramic radiographs in patients with CKD undergoing hemodialysis. Calcification was more frequent in older patients, women, individuals with diabetes mellitus, and patients who had undergone hemodialysis for longer periods.

Bacteria and Hard Tissue Debris Extrusion and Intracanal Bacterial Reduction Promoted by XP-endo Shaper and Reciproc Instruments.

INTRODUCTION: This study used a multipurpose analytic approach to compare the levels of apically extruded bacterial and hard tissue debris as well as intracanal bacterial reduction after root canal preparation with either XP-endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland) or Reciproc (VDW, Munich, Germany) instruments. METHODS: Distobuccal canals from extracted maxillary molars were contaminated with Enterococcus faecalis and randomly distributed into 2 groups according to the instrumentation system: the XP-endo Shaper or Reciproc. Teeth were mounted in an apparatus that simulates the apical resistance offered by the periapical tissues and permitted to collect debris extruded during preparation. Saline was used as the irrigant during preparation, and all treatment procedures were performed inside a cabinet under a controlled temperature of 37°C. DNA extracts from samples taken from the canal before and after preparation were subjected to quantitative real-time polymerase chain reaction for E. faecalis counting. The volume of extruded debris was evaluated by micro-computed tomographic imaging. DNA was extracted from the extruded hard tissue debris and analyzed by quantitative real-time polymerase chain reaction. RESULTS: Mechanical intracanal bacterial reduction was significantly more pronounced when using the XP-endo Shaper (P < .001). Although both instruments produced a similar volume of extruded debris (P > .05), extruded bacteria counts were significantly lower with Reciproc than the XP-endo Shaper (P < .001). No correlation was observed between the extruded bacterial counts and debris volume. CONCLUSIONS: Although bacterial extrusion was lower with Reciproc, the intracanal bacterial reduction was higher with the XP-endo Shaper. Both techniques produced a similar volume of hard tissue debris extrusion.

Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis.

This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%), Pseudoramibacter (10.7%) and Streptococcus (5.5%). Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection.

Advanced Caries Microbiota in Teeth with Irreversible Pulpitis.

INTRODUCTION: Bacterial taxa in the forefront of caries biofilms are candidate pathogens for irreversible pulpitis and are possibly the first ones to invade the pulp and initiate endodontic infection. This study examined the microbiota of the most advanced layers of dentinal caries in teeth with irreversible pulpitis. METHODS: DNA extracted from samples taken from deep dentinal caries associated with pulp exposures was analyzed for the presence and relative levels of 33 oral bacterial taxa by using reverse-capture checkerboard hybridization assay. Quantification of total bacteria, streptococci, and lactobacilli was also performed by using real-time quantitative polymerase chain reaction. Associations between the target bacterial taxa and clinical signs/symptoms were also evaluated. RESULTS: The most frequently detected taxa in the checkerboard assay were Atopobium genomospecies C1 (53%), Pseudoramibacter alactolyticus (37%), Streptococcus species (33%), Streptococcus mutans (33%), Parvimonas micra (13%), Fusobacterium nucleatum (13%), and Veillonella species (13%). Streptococcus species, Dialister invisus, and P. micra were significantly associated with throbbing pain, S. mutans with pain to percussion, and Lactobacillus with continuous pain (P < .05). Quantitative polymerase chain reaction revealed a mean total bacterial load of 1 × 10(8) (range, 2.05 × 10(5) to 4.5 × 10(8)) cell equivalents per milligram (wet weight) of dentin. Streptococci and lactobacilli were very prevalent but comprised only 0.09% and 2% of the whole bacterial population, respectively. CONCLUSIONS: Several bacterial taxa were found in advanced caries lesions in teeth with exposed pulps, and some of them were significantly associated with symptoms. A role for these taxa in the etiology of irreversible pulpitis is suspected.

Efficacy of instrumentation techniques and irrigation regimens in reducing the bacterial population within root canals.

The purpose of this study was to compare the in vitro intracanal bacterial reduction produced by using two instrumentation techniques and different irrigation methods. Root canals inoculated with Enterococcus faecalis were prepared by using the following techniques and irrigants: alternated rotary motions (ARM) technique, hand nickel-titanium files and 2.5% sodium hypochlorite (NaOCl) as irrigant; ARM technique and combined irrigation with 2.5% NaOCl and citric acid; ARM technique and combined irrigation with 2.5% NaOCl and 2% chlorhexidine gluconate; and Greater Taper rotary files, using 2.5% NaOCl as irrigant. Controls were instrumented by using the ARM technique and irrigated with sterile saline. Canals were sampled before and after preparation. After serial dilution, samples were plated onto Mitis-Salivarius agar, and the colony forming units that were grown were counted. All test techniques and solutions significantly reduced the number of bacterial cells within the root canal (p < 0.05). There was no significant difference between the experimental groups (p > 0.05). Nonetheless, all of them were significantly more effective than the control group (p < 0.05). These findings support the importance of using antimicrobial irrigants during the chemomechanical preparation, regardless of the solutions or instrumentation techniques used.

Type 2 diabetes mellitus and the prevalence of apical periodontitis and endodontic treatment in an adult Brazilian population.

INTRODUCTION: This cross-sectional study evaluated the prevalence of apical periodontitis (AP) and endodontic treatment in type 2 diabetic individuals as compared with nondiabetics from an adult Brazilian population. METHODS: Full-mouth radiographs from 30 type 2 diabetic and 60 age- and sex-matched nondiabetic individuals were examined, and the presence of AP lesions in untreated and root canal-treated teeth was recorded. The number of teeth and the prevalence of root canal treatment were also evaluated. RESULTS: AP was significantly more present in teeth from diabetic individuals (98/652, 15%) than in nondiabetic controls (162/1,368, 12%) (P = .05). A separate analysis of untreated and treated teeth revealed that significance was mostly because of the prevalence of AP in untreated teeth, which was 10% in diabetics and 7% in nondiabetics (P = .03). No significant difference between diabetics and nondiabetics was observed for the other parameters under study, including the prevalence of AP in root canal-treated teeth, the number of teeth in the oral cavity, the number of treated teeth per individual, the number of individuals with at least 1 AP lesion or 1 root canal treatment, and the number of teeth with AP per individual (P > .05). CONCLUSIONS: AP was significantly more prevalent in untreated teeth from type 2 diabetics. This suggests that diabetes may serve as a disease modifier of AP in the sense that individuals with diabetes can be more prone to develop primary disease. However, findings do not confirm that diabetes may influence the response to root canal treatment because treated teeth had no increased prevalence of AP when compared with controls.

Relationship between Fcgamma receptor and interleukin-1 gene polymorphisms and post-treatment apical periodontitis.

INTRODUCTION: Genetic polymorphisms have been reported to act as modifiers of diverse diseases and, as such, might theoretically influence the severity and response to treatment of apical periodontitis. The purpose of this study was to investigate the association of Fcgamma receptor and interleukin (IL)-1 gene polymorphisms with post-treatment apical periodontitis in Brazilian individuals. METHODS: The study population consisted of 18 patients with post-treatment apical periodontitis and 44 individuals with root canal-treated teeth exhibiting healthy/healing periradicular tissues (controls). Patients were typed for the following genes (alleles): FcgammaRIIA (R131 or H131), FcgammaRIIIB (NA1 or NA2), IL-1A (1 or 2), and IL-1B (1 or 2). RESULTS: No significant statistical differences were observed for all specific genotypes and almost all allele carriage rates of the test genes as well as combinations thereof with regard to association with disease (P > .05). Actually, only 2 genetic conditions were found to be associated with post-treatment apical periodontitis: carriage of allele H131 of the FcgammaRIIa gene (P = .04) and a combination of this allele with allele NA2 of the FcgammaRIIIb gene (P < .01). CONCLUSIONS: Data from the present study suggest that some conditions associated with polymorphism of Fcgamma receptor genes might influence the patient's response to endodontic treatment of teeth with apical periodontitis.

Bacteriologic investigation of the effects of sodium hypochlorite and chlorhexidine during the endodontic treatment of teeth with apical periodontitis.

OBJECTIVE: This clinical study was undertaken to compare the effectiveness of 2.5% sodium hypochlorite (NaOCl) and 0.12% chlorhexidine digluconate as irrigants in reducing the cultivable bacterial populations in infected root canals of teeth with apical periodontitis. STUDY DESIGN: According to stringent inclusion/exclusion criteria, 32 teeth with primary intraradicular infections and chronic apical periodontitis were selected and followed in the study. Bacterial samples were taken at the baseline (S1) and after chemomechanical preparation using either NaOCl (n = 16) or chlorhexidine (n = 16) as irrigants (S2). Cultivable bacteria recovered from infected root canals at the 2 stages were counted. Isolates from S2 samples were identified by means of 16S rRNA gene sequencing analysis. RESULTS: At S1, all canals were positive for bacteria, and the median number of bacteria per canal was 7.32 x 10(5) for the NaOCl group and 8.5 x 10(5) for the chlorhexidine group. At S2, the median number of bacteria in canals irrigated with NaOCl and chlorhexidine was 2.35 x 10(3) and 2 x 10(2), respectively. Six of 16 (37.5%) canals from the NaOCl group and 8 of 16 (50%) canals from the chlorhexidine group yielded negative cultures. Chemomechanical preparation using either solution substantially reduced the number of cultivable bacteria in the canals. No significant difference was observed between the NaOCl and chlorhexidine groups with regard to the number of cases yielding negative cultures (P = .72) or quantitative bacterial reduction (P = .609). The groups irrigated with NaOCl or chlorhexidine showed a mean number of 1.3 and 1.9 cultivable species per canal, respectively. The great majority of isolates in S2 were from gram-positive bacteria, with streptococci as the most prevalent taxa. CONCLUSIONS: The present findings revealed no significant difference when comparing the antibacterial effects of 2.5% NaOCl and 0.12% chlorhexidine used as irrigants during the treatment of infected canals.

Clinical and microbiological characteristics in predicting dentine caries progression

The purpose of this study was to evaluate the clinical aspect of dentine and its microbiota in predicting caries progression. The sample consisted of schoolchildren in the 7 to14 years age group. Treatment involved cavity preparation trough the clinical criterion of hardness, with the collection of carious and remnants dentine for microbiological analysis. The clinical aspect (color and consistency) of the dentine remmants was recorded and the teeth were restored using silver amalgam and glass ionomer cement as pulpal protector (baseline - BL). After 1 year the restoration was removed and after new clinical and microbiological analyses, the teeth were then restored. Microbiological samples were collected at both time-points and cultivated in sheep blood agar, in anaerobiosis for 48 hours. Bacterial growth was analyzed quantitatively. Semiquantitative and qualitative analysis of the bacteria was performed by hybridization with genomic DNA probes and the checkerboard method. A significant difference was observed between the aspect of dentine remnants at BL and at 1 year (p=0.0078). The amount of bacteria at BL and at 1 year did not differ significantly (p=0.37) and the microbiota of the carious dentine was predominantly composed of Gram-positive cocci. The removal of carious dentine based on the clinical criterion of hardness, followed by a well-adapted restoration, would determine the non-progression of caries. The few bacteria that still remained in the cavity would be no longer viable.

Este trabalho objetivou avaliar o aspecto clinico da dentina e sua microbiota na predicao da progressao de carie. A amostra foi constituida por individuos na faixa etaria de 7 a 14. O tratamento envolveu a remocao de tecido cariado pelo criterio clinico de dureza, o qual foi coletado analise microbiologica. Apos o mesmo, fez-se analise do aspecto clinico da dentina remanescente, bem como nova coleta microbiologica e restaurou- se os elementos com amalgama de prata, apos forramento com ionomero de vidro. Um ano apos, com a reabertura do dente, outra coleta microbiologica foi feita, bem como analise do aspecto clinico do tecido remanescente. O crescimento bacteriano foi analisado quantitativamente atraves de hibridizacao com sondas de DNA genomico e do metodo Checkerboard. Observou-se diferenca estatisticamente significativa entre o aspecto da dentina na linha base do estudo e um ano apos (p=0.0078). A quantidade de bacterias na linha base, em relacao a um ano depois do preparo, nao diferiu estatisticamente (p=0,37) e a microbiota predominante da dentina cariada foi composta de cocos Gram-positivos. A remocao de dentina cariada pelo criterio clinico de dureza, favorecida pela boa adaptacao da restauracao determinaram a nao progressao de carie. As poucas bacterias que ainda permaneceram na cavidade apos o preparo provavelmente tornaramse inviaveis em promover o avanco do processo carioso.