Antibacterial performance of composite containing quaternary ammonium silica (QASi) filler - A preliminary study.

BACKGROUND: Antibacterial composite will have a significant clinical advantage in controlling caries. This study tests the antibacterial properties of a novel bulk-fill flowable composite (Infinx™, Nobio™ Ltd.) containing quaternary ammonium silica (QASi) filler particles. METHODS: Infinix™ was tested in-vitro by the direct contact test (DCT), using E. faecalis or whole saliva as inoculum. A similar formula composite without QASi served as a control. In addition, composite test samples were polymerized on three volunteers' intact buccal enamel surfaces of mandibular first premolars in a split-mouth design experiment. Traditional composite served as control (Filtek Bulk Fill Flowable, 3M). Bacterial viability on the composite surfaces weres assessed ex-vivo microscopically six months later, using a fluorescent dead/live stain. Images of each bacterial sample were taken using a fluorescent microscope (Nikon Eclipse 80i), and further live/total cell analysis was performed using ImageJ software. RESULTS: Following direct contact with one week of aged Infinix, more than 1 million E. faecalis bacteria were killed. Similarly, when using the saliva as inoculum, no single microorganism survived. Six-month in-vivo experiments supported these results by showing a reduction of 54%, 30% and 28% in live/total number of bacteria ratio retrieved from antibacterial composite vs. the control in volunteers #1, #2, #3 respectively. CONCLUSION: Within the limitations of the experimental design, the present study suggest that antibacterial activity of quaternary ammonium silica particles (QASi) is comparable to that of previously described quaternary ammonium polyethyleneimine particles (QPEI). In addition, whole saliva bacteria are effectively killed by QASi-containing composite in-vitro and in-vivo, for a period of six month at least. Long-term full-scale clinical study is needed to confirm the findings of the present study and their implication on maintaining health balance. CLINICAL SIGNIFICANCE: Antibacterial composites containing QASi filler is a novel class of restoratives that may contributes to caries lesion control.

SOS teeth with advanced caries and sociodemographic indicators, health-related habits and dental attendance patterns: data from the Dental, Oral, Medical Epidemiological (DOME) nationwide records-based study.

BACKGROUND: "SOS teeth" are teeth that need to be treated first, and represent dental teeth with deep caries seen clinically and radiographically which may require root canal treatment or extraction. The aims of the present research were to study the associations of SOS teeth with: socio-demographic parameters, dental attendance patterns, health-related habits among young to middle-aged adults. METHODS: This cross-sectional records-based research analyzed data from the Dental, Oral, Medical Epidemiological (DOME) repository that captures comprehensive socio-demographic, medical, and dental databases of a nationwide sample of 132,529 records of dental attendees to military dental clinics for 1 year aged 18 to 50 years. RESULTS: SOS teeth had a significant positive association in the multivariate analysis with male sex [OR 1.137, 95% Confidence Interval (CI): 1.079-1.199], rural versus urban Jewish locality [OR 1.748 (1.082-2.825)], and consumption of sweetened beverages [OR 1.415 (1.337-1.496)]. SOS teeth retained significant negative associations (protective parameter) with academic [OR 0.647 (0.592-0.708)] and technicians (OR 0.616 (0.556-0.682)] compared to high school education, high [OR 0.437 (0.401-0.476)], and medium (OR 0.648 (0.598-0.702)] versus low socio-economic status, urban non-Jewish versus urban Jewish locality [OR 0.746 (0.693-0.802)], Asia (OR 0.658 (0.452-0.959)], North America (OR 0.539 (0.442-0.658)] and Israel [OR 0.735 (0.686-0.788)] versus western Europe birth countries. CONCLUSIONS: Health authorities should be familiar with this profile of the patient who is vulnerable to SOS teeth and formulate policies and allow the appropriate implementation of strategies in those in high-risk populations.

Patterns of Cone-Beam Computed Tomography (CBCT) Utilization by Various Dental Specialties: A 4-Year Retrospective Analysis from a Dental and Maxillofacial Specialty Center.

The study aimed to analyze the uses of cone-beam computed tomography (CBCT) in the diagnosis and treatment in various dental specialties. This 4-year cross-sectional study analyzed the records of 1409 individuals who underwent a CBCT at the Oral and Maxillofacial Center at Sheba Medical Center, Israel. The average age of the patients was 27.9 ± 11.5 (range: 9-86 years). Patients were referred for CBCT by the following departments: Oral and Maxillofacial Surgery (1063; 75.5%), Endodontics (182; 12.9%), Periodontology (122; 8.6%) and Orthodontics (42; 3.0%). Most CBCT radiographs evaluated the maxilla (774; 55.0%), followed by the mandible (481; 34.1%) and both (154; 10.9%). The target anatomical structures included: bone (694; 49.3%), teeth (307; 21.7%), and both jaws (408; 29.0%). The main indications for CBCT use were: assessment of anatomical structures and implant sites (787; 55.9%), determine root canals morphology (182; 12.9%), visualization of impacted teeth, tooth alignment, and localization (177; 12.6%), suspected cysts or tumors (148; 10.5%), evaluation of Temporomandibular joint disorders (106; 7.5%) and other reasons (9; 0.6%). In 279 (19.8%) of cases, the diagnosis changed following CBCT, mainly in Orthodontics tooth analysis (28 (66.7%); p < 0.001). Practitioners and health authorities should be aware of this baseline information regarding CBCT use in the diagnosis and assessment of various oral and maxillofacial pathologies, anomalies and tooth position relative to anatomic structures. Continuing research and publications of CBCT utilization and guidelines are recommended.

"Dental Cluster" Versus "Metabolic Cluster": Analyzing the Associations of Planned and Delivered Dental Procedures with Metabolic Syndrome, Utilizing Data from the Dental, Oral, Medical Epidemiological (DOME) Cross-Sectional Record-Based Nationwide Study.

There are conflicting results existing regarding the association between dental status and metabolic syndrome (MetS). The present research analyzed the associations of the sum of the standard dental unit (SDU) scores of planned (SDU-P) and delivered (SDU-D) dental procedures per patient with MetS components, consequences, and related conditions. The SDU score of each dental procedure represents the time and complexity of the executed procedure. This cross-sectional study analyzed data from the Dental, Oral, Medical Epidemiological (DOME) repository, which includes comprehensive socio-demographic, medical, and dental databases of a nationally representative sample of 132,529 military personnel. Univariate analyses revealed that SDU-P had statistically significant positive associations with all systemic morbidities related to MetS, while the SDU-D exhibited positive associations with some of the systemic morbidities and with lower ORs. SDU-P and SDU-D were associated with worse scores of auxiliary examinations used in the assessment of MetS components. SDU-P retained significant positive associations in the multivariate analysis with impaired glucose tolerance (IGT) (OR = 7.40 (1.91-28.57)), deep vein thrombosis (DVT) (OR = 5.61 (1.53-20.83)), obstructive sleep apnea (OSA) (OR = 5.05 (2.40-10.63)), and fatty liver (OR = 1.82 (1.17-2.84)). In contrast, obesity was the only systemic parameter retaining a significant association with SDU-D following multivariate analysis (OR = 1.47 (1.23-1.76)). It can be concluded that SDU-P, but not SDU-D, is a better predictor of systemic morbidities related to MetS. In other words, MetS is associated with a higher dental treatment needs burden, rather than with dental treatments performed de facto. Dental and general health authorities should collaborate and share information and focus on reducing common health-related risk factors, such as smoking and sugar consumption, in particular among high-risk populations, such as immigrants and those with lower SES and rural locality.

Enterococcus faecalis sustained infection induces macrophage pro-resolution polarization.

AIM: To investigate macrophage function in the presence of sustained infection with Enterococcus faecalis, a prevalent root canal resident in asymptomatic apical periodontitis. METHODOLOGY: The human monocyte cell line (THP-1) was differentiated into macrophages by exposure to phorbol myristate acetate (PMA), and the cultures were inoculated with E. faecalis for up to 48 h. At three time-points 90 min, 24 and 48 h after inoculation, the macrophages and their supernatants were examined. Assays included macrophage phagocytosis rate and vitality, bacterial survival, reactive oxygen species (ROS) production, mitochondrial activity, cytokine production and the expression of pro/anti-inflammatory M1/M2 markers. Also, periapical tissue from apicectomy samples of human endodontically treated teeth were collected for histological and immunofluorescent analysis. Statistical differences were analysed with RM ANOVA. RESULTS: E. faecalis were phagocytized, and subsequently, most of the macrophages underwent apoptosis and necrosis. The small population of macrophages that remained vital after 48 h post-inoculation harboured surviving bacteria. Despite a reduction in the number of macrophages over time, the mitochondrial activity of the surviving macrophages remained constant and external ROS decreased, whereas internal ROS increased. During the infection, a shift to a M2 macrophage population at 48 h post-infection was observed; the results were similar to those obtained in periapical human tissue biopsies (p < .05). CONCLUSIONS: The study portrays a continuous non-resolved infection with E. faecalis and activation of macrophages that are polarized to the M2 pro-resolution phenotype.

A Mouse Model for Studying the Development of Apical Periodontitis with Age.

Older age is associated with reduced immune function. Our aim was to study how age affects the development of apical periodontitis (AP). AP was induced in two age groups of mice (young vs. adult). Histological samples were stained by Hematoxylin Eosin, Brown and Brenn, and Tartrate-Resistant Acid Phosphatase. In addition, the samples were scanned by Micro-Computerized-Tomography (micro-CT) to evaluate apical constriction and periapical lesion size. Cell density in the periapical region was computationally assessed. Moreover, lesion immune cell populations were characterized by flow cytometry and immunofluorescence. The young group presented more canals with necrotic radicular pulp compared to the adults. There was no difference in bacteria location in the canals between the groups. Apical constriction size was larger in the young mice compared to the adults. The periapical cell density was higher in the young group, while the dominant immune cells in the lesions were neutrophils, which also exhibited the highest young/adult ratio. Immunofluorescence demonstrated neutrophils in the lesion. More osteoclasts were present in the lesions of the young mice, in correlation to the higher volume of bone resorption in this group. Overall, we conclude that the immune reaction to AP stimuli was attenuated in the adult mice compared to the young.

Cognitive Performance and Its Associations with Dental Caries: Results from the Dental, Oral, Medical Epidemiological (DOME) Records-Based Nationwide Study.

Relatively few studies have analyzed the association between cognitive performance and dental status. This study aimed to analyze the association between cognitive performance and dental caries. Included were data from the dental, oral, medical epidemiological (DOME) study; cross-sectional records-based research, which integrated large socio-demographic, medical, and dental databases of a nationally representative sample of young to middle-aged military personnel (N = 131,927, mean age: 21.8 ± 5.9 years, age range: 18-50). The cognitive function of draftees is routinely measured at age 17 years using a battery of psychometric tests termed general intelligence score (GIS). The mean number of decayed teeth exhibited a gradient trend from the lowest (3.14 ± 3.58) to the highest GIS category (1.45 ± 2.19) (odds ratio (OR) lowest versus highest = 5.36 (5.06-5.68), p < 0.001). A similar trend was noted for the other dental parameters. The associations between GIS and decayed teeth persisted even after adjusting for socio-demographic parameters and health-related habits. The adjustments attenuated the OR but did not eliminate it (OR lowest versus highest = 3.75 (3.38-4.16)). The study demonstrates an association between cognitive performance and caries, independent of the socio-demographic and health-related habits that were analyzed. Better allocation of resources is recommended, focusing on populations with impaired cognitive performance in need of dental care.

Hypertension and Its Associations with Dental Status: Data from the Dental, Oral, Medical Epidemiological (DOME) Nationwide Records-Based Study.

Conflicting results have been published regarding the associations between dental status and hypertension. This study aims to explore whether or not hypertension is associated with dental status among young to middle-aged adults. To that end, data from the Dental, Oral, Medical Epidemiological (DOME) study were analyzed. The DOME is a cross-sectional records-based study that combines comprehensive socio-demographic, medical, and dental databases of a nationally representative sample of military personnel. Included were 132,529 subjects aged 18-50 years who attended the military dental clinics for one year. The prevalence of hypertension in the study population was 2.5% (3363/132,529). Following multivariate analysis, the associations between hypertension and dental parameters were lost and hypertension retained a positive association with obesity (Odds ratio (OR) = 4.2 (3.7-4.9)), diabetes mellitus (OR = 4.0 (2.9-5.7)), birth country of Western Europe vs. Israeli birth country (OR = 1.9 (1.6-2.2)), male sex (OR = 1.9 (1.6-2.2)), cardiovascular disease (OR = 1.9 (1.6-2.3)), presence of fatty liver (OR = 1.8 (1.5-2.3)), the birth country Asia vs. Israeli birth country (OR = 1.6 (1.1-2.3)), smoking (OR = 1.2 (1.05-1.4)), and older age (OR = 1.05 (1.04-1.06)). Further analysis among an age-, smoking- and sex matched sub-population (N = 13,452) also revealed that the dental parameters lost their statistically significant association with hypertension following multivariate analysis, and hypertension retained a positive association with diabetes (OR = 4.08 (2.6-6.1)), obesity (OR = 2.7 (2.4-3.2)), birth country of Western Europe vs. Israel (OR = 1.9 (1.6-2.3)), cardiovascular disease (OR = 1.8 (1.5-2.2)), fatty liver (OR = 1.7 (1.3-2.3)), high school education vs. academic (OR = 1.5 (1.3-1.8)), and low socio-economic status (SES) vs. high (OR = 1.4 (1.03-1.8)). We analyzed the associations between C-reactive protein (CRP) and dental parameters and combined the statistically significant variables to create a dental inflammation score (DIS). This crated a final model with the appropriate weights written as follows: DIS = (periodontal disease × 14) + (the number of teeth that required crowns × 11) + (missing teeth × 75). The mean DIS was 10.106 ± 25.184, and it exhibited a weak positive association with hypertension in the univariate analysis (OR = 1.011 (1.010-1.012)). Receiver operating characteristic (ROC) analysis of the DIS against hypertension produced a failed area under the curve (AUC) result (0.57 (0.56-0.58)). Moreover, the DIS also lost its statistical significance association with hypertension following multivariate analysis. We conclude that hypertension had no statistically significant nor clinically significant association with dental status. The study established a profile of the "patient vulnerable to hypertension", which retained well-known risk factors for hypertension such as older age, male sex, smoking, diabetes, obesity, and fatty liver but not dental parameters.

Pre-Operative Oral Health-Related Quality of Life in Patients Attending Surgical Removal of Mandibular Third Molar Teeth.

The study aimed to measure the pre-operative oral health-related quality of life (OHRQoL) and to identify patient and teeth pathologies associated with worse OHRQoL among patients attending mandibular third molar tooth extraction. Data were collected preoperatively from 199 patients attending surgical removal of their mandibular third molar. To that end, we measured the Oral Health Impact Profile-14 (OHIP-14) and analyzed its association with: (1) demographics; (2) health-related behaviors such as smoking, alcohol consumption, physical activity, and dietary habits; (3) Plaque Index (PI); (4) Decay, Missing, and Filled Teeth (DMFT); and (5) clinical characteristics related to third molar extraction, such as the indication for extraction, tooth angulations, and radiographic pathology. The mean age of the study population was 21.5 ± 3.2 years and the mean OHIP-14 global score was 22.5 ± 8.3. The present study identified patient and teeth profiles that are associated with worse pre-operative OHRQoL in patients attending mandibular third molar extraction. The "vulnerable patient" profile includes poor health-related behaviors, particularly the performance of physical activity less than once a week (p = 0.028). The "disturbing teeth" profile includes higher plaque scores (p = 0.023) and specific characteristics of the third molar teeth, such as pericoronitis (p = 0.027) and radiolucency around third molars in panoramic radiography (p < 0.001). These findings support the hypothesis that OHRQoL is a complex phenomenon which is associated with the patient's health-related behaviors as well as with specific tooth pathologies.

SOS Teeth: First Priority Teeth with Advanced Caries and Its Associations with Metabolic Syndrome among a National Representative Sample of Young and Middle-Aged Adults.

"SOS teeth" are defined as the first priority teeth for treatment, that have distinct cavitation reaching the pulp chamber or only root fragments are present. These are teeth with severe morbidity, that may require pulp capping, root canal treatment, or extraction, and therefore should be treated first. The study aims to explore whether or not a metabolic syndrome (MetS) is associated with SOS teeth. To that end, we performed across-sectional records-based study of a nationally representative sample of 132,529 military personnel aged 18-50 years, who attended the military dental clinics for one year. The mean number of SOS had no statistically significant association with: smoking (p = 0.858), alcohol consumption (p = 0.878), hypertension (p = 0.429), diabetes mellitus (p = 0.866), impaired glucose tolerance (p = 0.909), hyperlipidemia (p = 0.246), ischemic heart disease (p = 0.694), S/P myocardial infarction (p = 0.957), obstructive sleep apnea (p = 0.395), fatty liver (p = 0.074), S/P stroke (p = 0.589), and S/P transient ischemic attack (p = 0.095) and with parental history of: diabetes (p = 0.396)], cardiovascular disease (p = 0.360), stroke (p = 0.368), and sudden death (p = 0.063) as well as with any of the medical auxiliary examinations (p > 0.05). Cariogenic diet was positively associated with SOS teeth (p < 0.001). We conclude that SOS teeth had no statistically significant association with MetS components or with conditions that are consequences or associated with MetS. The only statistically significant parameter was a cariogenic diet, a well-known risk factor for caries and MetS.

SOS Teeth: Age and Sex Differences in the Prevalence of First Priority Teeth among a National Representative Sample of Young and Middle-Aged Adults.

BACKGROUND: "SOS teeth" are defined as the first priority teeth for treatment, that have distinct cavitation reaching the pulp chamber or only root fragments are present. OBJECTIVES: To assess the prevalence and distribution of SOS teeth with regard to age and sex difference among young to middle-aged adults. METHODS: This is a cross-sectional records-based study of a nationally representative sample, consisting of young to middle-aged military personnel, who attended the military dental clinics of the Israel Defense Forces (IDF) for one year. SOS teeth definition corresponds to code number 6 of the "Caries Assessment Spectrum and Treatment (CAST)" as an instrument to assess dental caries. Data pertaining to age and sex were drawn from the central demographic database and that of SOS teeth were obtained from the Dental Patient Record (DPR). RESULTS: The study included 132,529 dental records. The prevalence of patients with SOS teeth was 9.18 % (12,146/132,323). The number of teeth that were found to be SOS teeth was 18,300, i.e., 1.5 SOS teeth per "diseased" patient (18,300/12,146). The mean number of SOS teeth per the whole study population was 0.14 ± 0.52 and the range was 0-20. The mean number of SOS teeth per patient had a statistically significant negative correlation with age (p < 0.001; Odds Ratio (OR) = 0.997; 95% confidence interval: 0.997-0.998) and with male sex compared to females (p < 0.001; OR = 1.029 confidence interval: 1.023-1.036). CONCLUSION: Assessment of first priority SOS teeth may be part of the dentist's work-up. It provides dentists and health authorities with useful information regarding urgent dental care needs to plan dental services.

Dental care during the coronavirus disease 2019 (COVID-19) outbreak: operatory considerations and clinical aspects.

OBJECTIVES: This paper is aimed at addressing the urgent need to develop a protocol that will address the operatory and clinical aspects of dental care during the Coronavirus disease 2019 (COVID-19) outbreak. DATA SOURCES: The epidemiology, clinical signs and symptoms, and modes of transmission of COVID-19 are presented. This protocol was established as an international collaboration of three dental universities: Hadassah School of Dental Medicine, Israel; University of Rochester Medical Center, USA; and the University of Pennsylvania, USA. This protocol is based on a detailed review of the existing English language literature as well on the logistic and clinical experience of each facility and the opinion of the authors. The protocol is designed for a hospital setting and includes considerations related to dental treatment in both healthy subjects and those suspected or diagnosed with COVID-19. The first part of this review discusses operatory considerations; the second part discusses general dental clinical aspects; the third part discusses endodontic considerations; and the fourth part discusses surgical aspects. This protocol may be applicable to other future similar pandemics. CONCLUSION: Logistic and clinical steps are required to provide dental care during the COVID-19 outbreak while preventing cross-contamination and protecting the dental team during the provision of care.

Inducing Apical Periodontitis in Mice.

The mechanisms involved in local induced inflammation can be studied using several available animal models. One of these is the induction of apical periodontitis (AP). Apical periodontitis is a common pathology of an inflammatory nature in the periodontal tissues surrounding the tooth root. In order to better understand the nature and mechanism of this pathology it is advantageous to perform the procedure in mice. The induction of this odontogenic inflammation is achieved by drilling into the mouse tooth until the dental pulp is exposed. Next, the tooth pulp remains exposed to be contaminated by the natural oral flora over time, causing apical periodontitis. After this time period, the animal is sacrificed, and the tooth and the jaw bone can be analyzed in various ways. Typical analyses include micro-CT imaging (to evaluate bone resorption), histological staining, immunohistochemistry, and RNA expression. This protocol is useful for research in the field of oral biology to better understand this inflammatory process in an in vivo experimental setting with uniform conditions. The procedure requires a careful handling of the mice and the isolated jaw, and a visual demonstration of the technique is useful. All technical aspects of the procedures leading to induced apical periodontitis and its characterization in a mouse model are demonstrated.

Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove.

The purpose of this study was to compare the effectiveness of self-adjusting file (SAF), XP-endo finisher (XP), passive ultrasonic irrigation (PUI) and conventional syringe and needle irrigation (SNI) in the removal of Ca(OH)2 from an artificial groove. Eighty mandibular incisors with single oval canals were prepared to size 40/0.04 and split longitudinally. A standardised groove was prepared in the apical third and filled with Ca(OH)2 . The root halves were reassembled and divided into two control groups (n = 4) and four experimental groups (n = 18) according to the removal methods used. The amount of residual Ca(OH)2 was evaluated using a four-grade scoring system. The differences among the groups were analysed using the Kruskal-Wallis test (P < 0.05). SAF, XP and PUI removed significantly more Ca(OH)2 than SNI (P < 0.001), although there were no significant differences among them (P = 0.209). None of the tested methods could completely clean Ca(OH)2 from the groove.

Occurrence of invasive cervical resorption after the completion of orthodontic treatment.

The invasive cervical resorption (ICR) is an irreversible and progressive loss of tooth hard tissues involving coronal and root dentine that usually affects single permanent teeth. The aim of this study was to present the pattern of ICR lesions detected in three patients with no contributory medical and dental anamnesis, at different time periods after orthodontic tooth movements. Conventional radiographs and cone-beam computed tomography (CBCT) images were obtained by X-Mind™ (Satelec), respective 3D Accuitomo (Morita). The present clinical study confirmed that orthodontic forces might be a key factor for generating an ICR and the risk of lesion occurrence is increased in long movements of the teeth because the orthodontic forces act continuously an extended time. However, it should not be overlooked the synergistic effect of additional factors such as traumatic injuries, periodontal inflammation, clenching, and grinding. The more advanced ICR lesions found in our study, described as Heithersay Class 3 and Class 4, appeared on conventional radiographs as irregular, diffuse, mottled radiolucencies extended both to the crown and deeply into the tooth root. CBCT proved to have a superior accuracy in detection and assessing the severity of ICR, since the conventional intraoral radiographs cannot afford an early and proper identification of the resorptive defect. Moreover, the CBCT image allows an accurate inspection of all surfaces of tooth due to the slices in sagittal, axial and coronal planes, and to avoid erroneous diagnostic conclusions. Currently, due to CBCT scan, the nature and extension of ICR lesion into the tooth structures can be exactly evaluated.

The effects of sinus membrane pathology on bone augmentation and procedural outcome using minimal invasive antral membrane balloon elevation.

Membrane pathology tends to complicate the postprocedural course of open sinus lift by ostio-meatal complex (OMC) obstruction and consequent acute sinusitis. The objective of this study was to evaluate the outcome of subjects with considerable sinus membrane pathology undergoing maxillary sinus floor augmentation and simultaneous implant placement using the minimal invasive antral membrane balloon elevation (MIAMBE) method. This study was a retrospective chart review of MIAMBE procedures performed in the presence of significant sinus membrane pathology. Sixteen patients with maxillary sinus membrane thickening in well-ventilated OMC as determined by dental computerized tomography underwent sinus augmentation and simultaneous implant placement using the MIAMBE technique. All 16 procedures were successfully concluded without significant procedural or postprocedural complications or implant failure. Post MIAMBE membrane pathology regressed or disappeared in 8 patients (50%) or remained unchanged in 6 patients (37.5%), while in 2 patients the sinus membrane pathology was limited to evaluation by periapical X rays. Sinus augmentation using the MIAMBE technique can be performed safely in asymptomatic patients in the presence of sinus membrane pathology if the OMC is not obstructed. In a significant proportion of these cases, complete resolution of the membrane pathology after MIAMBE is observed. When compared to open sinus lift, OMC obstruction is less likely to occur when employing the MIAMBE method.

Rapid kill-novel endodontic sealer and Enterococcus faecalis.

With growing concern over bacterial resistance, the identification of new antimicrobial means is paramount. In the oral cavity microorganisms are essential to the development of periradicular diseases and are the major causative factors associated with endodontic treatment failure. As quaternary ammonium compounds have the ability to kill a wide array of bacteria through electrostatic interactions with multiple anionic targets on the bacterial surface, it is likely that they can overcome bacterial resistance. Melding these ideas, we investigated the potency of a novel endodontic sealer in limiting Enterococcus faecalis growth. We used a polyethyleneimine scaffold to synthesize nano-sized particles, optimized for incorporation into an epoxy-based endodontic sealer. The novel endodontic sealer was tested for its antimicrobial efficacy and evaluated for biocompatibility and physical eligibility. Our results show that the novel sealer foundation affixes the nanoparticles, achieving surface bactericidal properties, but at the same time impeding nanoparticle penetration into eukaryotic cells and thereby mitigating a possible toxic effect. Moreover, adequate physical properties are maintained. The nanosized quaternary amine particles interact within minutes with bacteria, triggering cell death across wide pH values. Throughout this study we demonstrate a new antibacterial perspective for endodontic sealers; a novel antibacterial, effective and safe antimicrobial means.

Antibacterial temporary restorative materials incorporating polyethyleneimine nanoparticles.

OBJECTIVES: Temporary restorative materials (TRMs) often rapidly lose their dimensional stability and antibacterial properties after exposure to humidity and bacterial infection. Quaternary ammonium polyethyleneimine (QPEI) nanoparticles (NP) are long-lasting, stable, biocompatible, and nonvolatile antibacterial polymers. In the present study, we incorporated QPEI NP into standard TRMs and examined their influence on dimensional stability and their ability to reduce bacterial leakage. METHOD AND MATERIALS: A modified split-chamber model was used in vitro to test calcium sulfate-based and zinc oxide-eugenol- based TRMs (Coltosol and IRM, respectively). Both materials were tested with and without 2% wt/wt incorporated QPEI NP for fluid and bacterial leakage. RESULTS: The calcium sulfate-based TRM displayed the lowest microleakage and highest antibacterial resistance. Two-way A NOVA analysis of the fluid transport test results showed that incorporation of 2% wt/wt QPEI NP significantly increased the sealing ability of both TRMs (P < .01). Analysis of survival curves by the Kaplan-Meier method showed that the calcium sulfate-based TRM with 2% wt/wt QPEI NP survived the bacterial load significantly more effectively than did the zinc oxide-eugenol-based TRM (P < .0001). CONCLUSION: Incorporation of 2% w/w QPEI NP may prominently improve the sealability and the antibacterial properties of TRMs. TRMs incorporating antibacterial nanoparticles may be clinically advantageous for sealing the endodontic access cavity to avoid reinfection of the root canal system during endodontic treatment.

Failure of treatment of impacted canines associated with invasive cervical root resorption.

OBJECTIVES: To propose invasive cervical root resorption (ICRR) as an unrecognized and/or overlooked etiologic factor in the failure of response of an impacted tooth to orthodontic traction and to underline the importance of cone beam computerized tomography (CBCT) for early and accurate diagnosis of ICRR. MATERIALS AND METHODS: Fourteen patients (age 13-21 years) with impacted canines (15 canines) that had failed to respond to orthodontic forces and that exhibited ICRR formed the case series for this investigation. The initial diagnosis, treatment, clinical and radiographic expression of failure, and adverse effects on adjacent teeth were analyzed. RESULTS: Initial diagnosis had been performed on plane radiographs. The orthodontist was absent during surgery in 11 patients. Nine canines had been exposed by open procedures. ICRR was not related to the severity of impaction. Its diagnosis was made on existing radiographs, new films, and/or new CBCT. The severity of the lesions was Class 3 or 4, and the teeth were finally extracted. Loss of anchorage characterized 11 patients. Apical resorption of the roots of adjacent teeth was diagnosed in 9 patients. CONCLUSIONS: ICRR is a frequently undiagnosed or unrecognized cause of failure of orthodontic resolution of impacted canines and should be distinguished from replacement resorption. CBCT should be used for its early detection and accurate assessment of potential damage to adjacent anchor teeth.

Immediate root canal disinfection with ultraviolet light: an ex vivo feasibility study.

OBJECTIVE: The study was designed to test application of ultraviolet light to root canal walls, as a mean of complementary immediate disinfection after the use of sodium hypochlorite. STUDY DESIGN: Root canals were infected ex vivo with Enterococcus faecalis for 48 hours. Non-attached bacteria were washed away, and the remaining attached bacteria were subjected to disinfection, with 5% sodium hypochlorite alone or followed by exposure to ultraviolet light (254 nm, 300 mJ/cm(2)). Root canals were then tested for remaining viable bacteria. Canals were obturated and tested again after 14 days. RESULTS: Sodium hypochlorite alone achieved negative cultures in only 47% of the cases, but 96% was achieved with sodium hypochlorite followed by ultraviolet light (P < .001). This status was also maintained after 14 days. CONCLUSIONS: Illumination of root canals with ultraviolet light may be an effective supplementary means to achieve immediate disinfection of infected root canals.