Comparison of shear bond strength of composite resin, compomer, and resin-modified glass-ionomer cements in primary teeth: An in-vitro study.

OBJECTIVE: The contemporary esthetic restorative materials such as composite resin and glass-ionomer cements and their modifications have all been developed keeping in mind the requirements of permanent teeth. There have been plenty of studies that have focused on the characteristics of these materials in relation to permanent teeth with a relative dearth of such studies as regard to the primary teeth. The present study was undertaken to compare and evaluate the shear bond strength of composite resin, compomer, and resin-modified glass-ionomer cements in primary teeth. METHODS: Thirty non-carious primary molars that were indicated for extraction because of physiological resorption or, for orthodontic reasons, were selected. The selected teeth were randomly allocated to three groups of 10 each for composite, compomer, and resin-modified glass-ionomer cements. The enamel from the occlusal surface of all teeth was removed to expose the superficial dentin and was wet polished with 400 grit sand paper. Composite, compomer, and resin-modified glass-ionomer stubs were bonded on to the occlusal surfaces using a plastic tube as a template. All samples were, then, subjected to thermocycling and evaluation of shear bond strength using the universal testing machine at a cross-head speed of 0.5 mm/min, whereas the results obtained were subjected to statistical analysis. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) version 17.0 (SPSS Inc., Chicago, IL, USA), whereas one-way analysis of variance (ANOVA) and Tukey's multiple post-hoc procedures were used for statistical analysis. A P < 0.05 was considered statistically significant. RESULTS: The mean shear bond strength values for Groups I, II, and III were found to be 11.7 ± 3.07 MPa, 7.74 ± 4.16 Mpa, and 4.43 ± 2.08 Mpa, respectively, whereas one-way ANOVA and Tukey's multiple post-hoc procedures indicated that there were remarkable differences among the three groups with the results being statistically significant (P < 0.05). CONCLUSIONS: Composite resin showed the highest shear bond strength in relation to primary dentin when compared to compomer and resin-modified glass-ionomer cements.

TRAF3IP2-IL-17 Axis Strengthens the Gingival Defense against Pathogens.

Recent genome-wide association studies have suggested novel risk loci associated with periodontitis, which is initiated by dysbiosis in subgingival plaque and leads to destruction of teeth-supporting structures. One such genetic locus was the tumor necrosis factor receptor-associated factor 3 interacting protein 2 (TRAF3IP2), a gene encoding the gate-keeping interleukin (IL)-17 receptor adaptor. In this study, we first determined that carriers of the lead exonic variant rs13190932 within the TRAF3IP2 locus combined with a high plaque microbial burden was associated with more severe periodontitis than noncarriers. We then demonstrated that TRAF3IP2 is essential in the IL-17-mediated CCL2 and IL-8 chemokine production in primary gingival epithelial cells. Further analysis suggested that rs13190932 may serve a surrogate variant for a genuine loss-of-function variant rs33980500 within the same gene. Traf3ip2 null mice (Traf3ip2-/-) were more susceptible than wild-type (WT) mice to the Porphyromonas gingivalis-induced periodontal alveolar bone loss. Such bone loss was associated with a delayed P. gingivalis clearance and an attenuated neutrophil recruitment in the gingiva of Traf3ip2-/- mice. Transcriptomic data showed decreased expression of antimicrobial genes, including Lcn2, S100a8, and Defb1, in the Traf3ip2-/- mouse gingiva in comparison to WT mice prior to or upon P. gingivalis oral challenge. Further 16S ribosomal RNA sequencing analysis identified a distinct microbial community in the Traf3ip2-/- mouse oral plaque, which was featured by a reduced microbial diversity and an overabundance of Streptococcus genus bacteria. More P. gingivalis was observed in the Traf3ip2-/- mouse gingiva than WT control animals in a ligature-promoted P. gingivalis invasion model. In agreement, neutrophil depletion resulted in more local gingival tissue invasion by P. gingivalis. Thus, we identified a homeostatic IL-17-TRAF3IP2-neutrophil axis underpinning host defense against a keystone periodontal pathogen.

Variations in Canal Morphology, Shapes, and Positions of Major Foramen in Maxillary and Mandibular Teeth.

CONTEXT AND AIM: A plethora of studies have revealed that there is a lack of general consensus in the precise anatomic detailing of the canals and the major foramen in both the maxillary and mandibular teeth while emphasizing the significance of the same for a successful endodontic treatment. The aim of the present study was to determine the variations in canal morphology, shapes, and positions of major foramen in maxillary and mandibular teeth. MATERIALS AND METHODS: In the present study, 420 extracted human maxillary and mandibular teeth with completely formed apices were included. The specimens were cleaned for surface debris including remnants of periodontal tissue and were stored in saline. Examination of the apices was performed with the help of stereomicroscope for their exact shapes and configurations and precise anatomic location. Comparison of different parameters within the group was done using Chi-square test while P < 0.05 was considered statistically significant. RESULTS: The results of the present study indicated that apical foramen in mandibular teeth showed higher degree of deviation with a prevalence of 70.2% while flat shape of apical foramen was observed only in maxillary teeth. Furthermore, maximum deviation in maxillary teeth was recorded in the canines with a prevalence of 90% while, in mandibular teeth, maximum deviation was recorded with mandibular second premolars with a prevalence of 79.12%. CONCLUSIONS: The results of the present study revealed that deviation of apical foramen from the root apex was seen in 68.2% of the specimens. Furthermore, deviation was greater in the mandibular than the maxillary teeth.

Assessment of the viability of human periodontal ligament cells in black tea, lime juice, and passion fruit concentrate - A comparative in vitro study.

BACKGROUND: Tooth avulsion is considered as a severe form of dental trauma, causing damage to the periodontium. Hence, the preservation of healthy periodontal ligament (PDL) cells in the storage medium are pivotal for the success of replantation. AIM AND OBJECTIVE: The aim of this study is to assess the viability of human PDL cells in black tea, lime juice, and passion fruit concentrate. METHODS: Human periodontal cells were cultured and stored in three experimental media - black tea, lime juice, and passion fruit concentrate and subjected to 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay for 1 h and the cell viability was determined. Mean and standard deviation were statistically analyzed using one-way analysis of variance to identify the significant groups. RESULTS: The human PDL cells showed 100% viability in lime juice and passion fruit concentrate, followed by 98% viability in black tea. CONCLUSION: Black tea, lime juice, and passion fruit concentrate can be used effectively as storage media for maintaining PDL cells viability in avulsed teeth, with 100% viability exhibited by lime juice and passion fruit concentrate.

Salivary pH and Buffering Capacity as Risk Markers for Early Childhood Caries: A Clinical Study.

BACKGROUND: The diagnostic utility of saliva is currently being explored in various branches of dentistry, remarkably in the field of caries research. This study was aimed to determine if assessment of salivary pH and buffering capacity would serve as reliable tools in risk prediction of early childhood caries (ECC). MATERIALS AND METHODS: Paraffin-stimulated salivary samples were collected from 50 children with ECC (group I) and 50 caries free children (group II). Salivary pH and buffering capacity (by titration with 0.1 N hydrochloric acid) were assessed using a handheld digital pH meter in both groups. The data obtained were subjected to statistical analysis. RESULTS: Statistically, no significant difference was observed between both the groups for all salivary parameters assessed, except for the buffering capacity level at 150 µl titration of 0.1 N hydrochloric acid (p = 0.73; significant at 1% level). CONCLUSION: Salivary pH and buffering capacity may not serve as reliable markers for risk prediction of ECC. How to cite this article: Jayaraj D, Ganesan S. Salivary pH and Buffering Capacity as Risk Markers for Early Childhood Caries: A Clinical Study. Int J Clin Pediatr Dent 2015;8(3):167-171.

In vivo autofluorescence characteristics of pre- and post-treated oral submucous fibrosis: a pilot study.

AIMS AND OBJECTIVES: To compare the autofluorescence spectra of oral submucous fibrosis (OSF) with normal mucosa, the autofluorescence spectra of OSF before and after treatment with intralesional dexamethasone and hyaluronidase, the clinical improvement following treatment with the changes in autofluorescence spectra and to prove that autofluorescence spectroscopy is a good method for diagnosis and assessment of treatment effectiveness in OSF. MATERIALS AND METHODS: The study was conducted at the Department of Oral Medicine and Radiology, Tamilnadu Government Dental College and Hospital, Chennai and Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai in 20 patients seeking medical management for symptomatic OSF and 20 patients who had dental caries only without any oral mucosal diseases and oral habits were used as normal controls. Their ages ranged from 20 to 40 years, including both male and female. In vivo fluorescence emission spectra were obtained using a handheld optical fiber probe attached to a Fluoromax-2 spectrofluorometer. RESULTS: The fluorescence spectrum of OSF had an intense fluorescence emission at 385 nm with a secondary emission peak at 440 nm compared with that of the normal oral mucosa. The average fluorescence spectrum of the post treated OSF mucosa had a lesser intensity around 385 nm and a higher intensity around 440 nm than that of the pre treated OSF mucosa, thereby mimicking the normal oral mucosa. All the three clinical parameters (maximal mouth opening, tongue protrusion and the severity of burning sensation) showed a high statistical significance, with P < 0.001, as in the case of classification of pre treated OSF mucosa from the post treated OSF mucosa using the autofluorescence technique. CONCLUSION: The change in the fluorescence emission spectrum for both normal and OSF mucosa before and after treatment can be explained by analyzing the changes in the fluorescence intensity of the endogenous fluorophores.

Switching from other antipsychotics to once-daily extended release quetiapine fumarate in patients with schizophrenia.

OBJECTIVE: To evaluate the clinical benefit, efficacy and tolerability of switching patients experiencing suboptimal efficacy or tolerability with their current antipsychotic to once-daily extended release quetiapine fumarate (quetiapine XR). RESEARCH DESIGN AND METHODS: 12-week, multicenter, open-label study in adult, in- or outpatients with schizophrenia. Quetiapine XR (mg/day) was initiated during a 4-day cross-titration phase (day 1: 300; day 2: 600; days 4-84: 400-800 [flexible-dosing]). The primary endpoint was the percentage of patients achieving clinical benefit (improvement on the Clinical Global Impression-Clinical Benefit [CGI-CB] scale). Secondary endpoints included CGI-Improvement (CGI-I) and Positive and Negative Syndrome Scale (PANSS) total scores. Tolerability was assessed by adverse events (AEs), Simpson-Angus Scale (SAS) and Barnes Akathisia Rating Scale (BARS) scores. Changes in rating scale scores were analyzed using analysis of covariance and are presented as least squares mean (LSM) changes using the baseline level as a covariate. RESULTS: Of 477 patients switched to quetiapine XR, 77.6% completed treatment. Following switching, 295 of 470 patients adequate for evaluation (62.8%) achieved a clinical benefit (95% confidence interval [CI] 58.4, 67.1; p < 0.0001). Significant improvements in LSM (95% CI) CGI-I of 2.88 (2.67, 3.08) and the LSM change in PANSS total scores of -12.3 (-14.95, -9.58) were observed (both p < 0.001). Common AEs included somnolence (17.8%), sedation (15.1%), dizziness and dry mouth (14.0% each). The incidence of extrapyramidal symptoms (EPS) was 8.0%. Mean improvements from baseline in SAS and BARS scores were -2.1 and -0.4, respectively (both p < 0.001). CONCLUSIONS: Switching to quetiapine XR was associated with clinical benefit and good efficacy and tolerability.

Alveolar liquid pressures in nonedematous and kerosene-washed rabbit lung by micropuncture.

We studied the relationship between alveolar interfacial pressure and lung volume in kerosene-filled lungs, nonedematous air-filled lungs on lung deflation and inflation, and air-filled lungs after washing with kerosene or the Dow Corning oil, 0.65 cs dimethyl siloxane (DC200). We used the micropipet-servonulling technique to measure alveolar liquid pressure (Pliq) in the alveolar liquid layer of isolated rabbit lungs at different airway pressures (Palv). It was not possible to measure pressure in kerosene or in DC200 by micropuncture because of its low electrical conductivity. We used the Laplace law for a spherical membrane to estimate alveolar surface tension (T). In the kerosene-filled lung, the pressure drop (delta P = Pliq - Palv) across the alveolar surfactant-kerosene interface was 1.1 cm H2O at TLC and decreased to 0.5 cm H2O at 71% TLC. These values corresponded to T values of 2.2 and 0.9 dyne/cm at TLC and 71% TLC, which were in agreement with in vitro measurements using the captive bubble technique. In the air-filled lung on inflation, delta P values were 12.7 and 15.7 cm H2O at 48% and 76% TLC. Corresponding T values were 14 and 21 dyne/cm. Thus, alveolar surface tension on lung inflation is surface area dependent. In the kerosene-washed and DC200-washed lungs, delta P values were 16 and 14.5 cm H2O at TLC and decreased to 9 and 8 cm H2O at 50-56% TLC. These values indicated a reduction of 40-60% in alveolar surface tension with lung deflation from TLC to 50% TLC. The results indicate that alveolar surface tension in both kerosene-filled and kerosene-washed air-filled lungs is surface area dependent. This is due to a surfactant-kerosene interface in the kerosene-filled lung and a surfactant-kerosene-air interface in the kerosene-washed lung.

Stromal changes in apparently normal mucosa of smokers and pan chewers: a multi-parametric approach

Aim: To compare and contrast the various changes in the connective tissue among patients with the habits of smoking, pan chewing and controls by using fluorescence spectroscopy, histopathology and transmission electron microscopy. Method: Thirty subjects were categorized into three groups: pan chewers, smokers and controls without any oral lesions. Fluorescence spectroscopy was carried out using FLUOROMAX-2. Excitation spectroscopy was performed at 280 and 320nm respectively and Emission spectroscopy was performed at 340 and 390nm excitation. Subsequently, histopathological evaluation and transmission electron microscopy was done for biopsies taken from test groups and controls. Results: The mean, standard deviation and test of significance of mean values between different groups for intensity-380nm, intensity–420nm and intensity – 460nm at 320 nm excitations, showed that the Mean values in group I and group II were significantly higher than the mean value in group III with a p-value of less than 0.001. Considering the histopathological parameters, the pattern of the sub-epithelial connective tissue, the presence of chronic inflammatory cells and lysis of connective tissue was significant. The ultrastructural analysis revealed the presence of epithelioid, spindle or elongated and stellate shaped fibroblasts in the connective tissue. Conclusion: In this pilot study, we could find variations in emission characteristics of various amino acids which correlated with histopathology and electron microscopy. Our study suggests that there are connective tissue changes in oral mucosa among smokers and pan chewers, though it is apparently normal in clinical presentation. These initial connective tissue changes could determine the progression of altered mucosa to a pre-cancer or cancer, which is further related to other complex interactions. Elaborate studies are required to evaluate the significance of our hypothesis.