<p> Background: Corticosteroid medications have been researched extensively in oral surgery procedures for the proposed reduction in trismus, swelling, and pain. No consensus has been determined for the most efficacious type, timing, and dosage of medication thus far. In addition little is known about the usage of corticosteroids for periodontal and implant related procedures. The aims of this review are to help clinicians understand the usage of corticosteroid medications in various dental surgeries. </p><p> Methods: The PubMed-MEDLINE and the Cochrane-CENTRAL databases were searched through and up till June 2015 to identify appropriate studies regarding this aim. Appropriate studies were those reporting on the usage of corticosteroids related to its pathophysiology, surgical related outcomes, and patient related outcomes in dental procedures. </p><p> Conclusions: The search yielded 256 unique papers after selection resulted in 12 publications that met the eligibility criteria. In general the usage of corticosteroids in third molar extractions improved post operatives outcomes related to edema, trismus, and a slight reduction in pain. However, It cannot be recommended to use corticosteroids for pain management. Due to the various types, routes, and dosages of corticosteroid used in studies, no specific drug, route, or dosage can be recommended by literature. The usage of corticosteroids for periodontal and implant related procedures has not been investigated. Further research is required to investigate the possible benefits of corticosteroids on reduction of surgical swelling in periodontal and implant related surgeries. </p>

The method of principal components may be used to reduce a large quantity of data for an individual into a single statistic, a growth index, indicative of overall facial growth, and to make a determination of the relative contribution of each variable, as well as the genotype and the environment, to the variation between individuals, When this method is applied to four consecutive years of cephalometric and anthropometric data from each of 95 children, consisting of Caucasian and Negro monozygotic twins, like-sexed dizygotic twins, and their siblings of both sexes, it discloses that: 1. The relative contributions of the variables studied to the variation among individuals are as follows: facial depth variables > facial height variables > facial width variables. 2. No differences in growth rates, as represented by the growth index, are apparent between males and females entering the study during the same age interval, between members of the same sex entering the study during two age intervals, between sexes including all age intervals, and between races. Failure of the investigation to disclose any such differences may result from the design of the experiments. 3. A very highly significant environmental component of variability for the growth index is found in the population studied, which suggests the need for further studies of specific environmental agents affecting the growth rates of the variables involved. 4. A very highly significant genetic component of variability for the growth index also is found, however, the complicated polygenic nature of facial inheritance renders analysis of the specific genetic factors involved quite difficult, because of the present limited knowledge of the inheritance of quantitative traits. 5. A very highly significant extrafamilial (genetic and environmental) component of variability for the growth index also is found. 6. The sources of variability for the growth index for twins, have the following relative magnitudes: extra-familial > genetic > environmental > error. For siblings the relative magnitudes of the sources of variability are: extrafamilial > environmental> genetic > error. Thus, as expected, environmental factors are relatively more important between siblings than between twins.

<p> Screw-retained zirconia implant crowns with an internal titanium base have favorable mechanical properties compared to single piece zirconia implant crowns; however, they require adequate bonding between the zirconia crown and the titanium base. This study measures the retention between a titanium base and a full contour zirconia implant crown following different surface treatments of their bonded surfaces. </p><p> Full contour zirconia implant crowns were fabricated to fit a 3.5mm titanium base. The crowns were bonded to the titanium bases following 4 protocols (n=15): no surface treatment (Group 1), MDP-primer on the intaglio of crown and exterior of base (Group 2), alumina particle abrasion of the intaglio of crown and exterior of base (Group 3), and alumina particle abrasion and an MDP-primer on the intaglio of crown and exterior of base (Group 4). All crowns were bonded to the base with resin cement. Specimens were stored in water for 24 hours at 37&deg;C and then thermocycled between 5&deg;-55&deg;C water for 15,000 cycles with a 15 second dwell time. Crowns were separated from the titanium bases using a universal testing machine. The four protocols were compared using a one-way ANOVA, followed by Tukey&rsquo;s post-hoc tests (alpha=0.05). Sectioned specimens were examined with SEM. </p><p> Retention forces for Group 1 (737.8&plusmn;148.9 N) and Group 2 (804.1 &plusmn;114.5 N) were significantly greater than Group 4 (595.5 &plusmn;122.2 N) which was significantly greater than Group 3 (428.2 &plusmn;93.8 N). Visual inspection of the debonded specimens showed that the majority of the cement remnants were seen on the external surface of the titanium bases. Microscopic examination of the interface between the crown and the unaltered base shows that the cement gap is approximately 13&mu;m at the crest of the microgrooves and 50&mu;m within the channel of the microgrooves. After particle abrasion, the microgrooves become significantly dulled and the cement gap increased to 27-40&mu;m at the crest and 55-58&mu;m in the channels. </p><p> Particle abrasion of titanium bases that contain retentive microgrooves prior to bonding is contraindicated. Application of a 10-MDP-primer demonstrated limited improvement in the retention of the zirconia implant crowns.</p>

Purpose: This study evaluated microleakage associated with cast restorations that were luted with a resin-modified glass ionomer cement (RelyX) following obturation of the dentinal tubules with either a desensitizing agent (Gluma Desensitizer) or an adhesive system (Scotchbond Multipurpose Dental Adhesive). The effect of acid etching on the removal of the smear layer and its influence on the extent of microleakage associated with the adhesive system was also evaluated. Materials and Methods: Extracted mandibular premolars (N = 48) were prepared for complete cast restorations and divided into 4 groups (N = 12). In group A ( control), neither a desensitizing agent or a component of the adhesive system was applied prior to luting. In group B, Gluma Desensitizer was used to obturate the dentinal tubules. In group C, Scotchbond Multipurpose Dental Adhesive System was applied to tooth preparations according to the manufacturer's instructions. Tooth preparations in group D received the same dentin surface treatment as in group C, but no acid etching was performed. Cast restorations in all 4 groups were then luted with the resin-modified glass ionomer luting cement RelyX. All specimens were subjected to thermocycling between 8° and 55°C for 500 cycles in water baths, placed in a solution of 0.5% basic fuchsin dye for 24 hours, and then sectioned twice longitudinally, once mesiodistally and then buccolingually. All specimens were examined at X30 magnification with a stereomicroscope equipped with a digital camera. Photographs of all sections were made and the extent of microleakage along the tooth-cement interface was measured in millimeters using an image analysis software. Microleakage was perceived to have occurred along a segment of the tooth-luting cement interface when dye penetration from that segment into the dentinal tubules was detected. One-way analysis of variance (α = 0.05) was performed to identify differences in mean microleakage among the luting groups, followed by Tukey's Honestly Significant Difference Test for pairwise comparisons. Results: Large standard deviations were found in all 4 groups. No statistically significant difference was found among the control (0.64 ± 0.50 mm), Gluma Desensitizer (0.42 ± 0.24 mm), and Scotchbond Multipurpose without etching (0.67 ± 0.40 mm) groups. However, a statistically significant difference was found between the Scotchbond Multipurpose with etching (1.51 ± 0.92 mm) group and each of the other groups. Conclusions: The large standard deviations obtained implied a marked amount of variability in microleakage within each group, which might be the result of the small sample size used. The increase in microleakage when 35% phosphoric acid was used prior to dentin bonding is difficult to explain. Within the limitations of the study, the results suggest that the use of a nonpolymerizing, resin-based (Gluma Desensitizer) material or a photopolymerizing, resin-based (Scotchbond Multipurpose) system without etching had no effect on microleakage under cast restorations luted with the resin-modified glass ionomer luting cement RelyX. The increase in microleakage when etching with 35% phosphoric acid was preformed might be explained by the phenomenon known as nanoleakage, but further investigation is recommended in this area.

AIM & HYPOTHESIS: We hypothesized that Diabetic ex-vivo bone model can be created by culturing the calvarial bone in BSA media which contains a high glucose level with lack of insulin hormone. Insulin has a direct effect on bone toward bone formation and can be as a local measure to enhance bone healing in critical bone defects and in bone regeneration with the use of bone graft substitutes. Chick embryo model can be used as an effective in-vivo model system to study bone biology. MATERIALS & METHODS: We utilized an ex-vivo diabetic calvarial bone culture system to evaluate the effect of insulin on bone biology under conditions of static versus dynamic, and formation versus resorption in order to interpret cellular and biological impact induced by insulin. In addition, we tested the effect of insulin on healing of critical bone defect with different bone graft material such as demineralized freezed dried bone (DFDBA) using ex-vivo calvarial bone model.  Also, we evaluated the efficacy of using chick embryo model as a bone regeneration model system. RESULTS: In our resorption and formation model insulin induced osteoblastic bone formation. In the calvarial defect repair model the defect healed much faster in the presence of insulin with complete closure of the defect at 40 days. EMD showed superior regenerative effect on bone defect compared to other variables used both at 21 and 40 days. Chick embryo model showed that all transplanted calvarial bones were vital and integrated to the embryonic membrane. CONCLUSION: Insulin has a direct positive effect on bone biology by enhancing osteoblast differentiation which indirectly suppresses the osteoclast differentiation and bone resorptive effect of PTH. The results of our studies demonstrated the potential of using an ex-vivo live craniofacial bone organ culture models using critical defects with the capacity to test rapidly and cost effectively bone graft materials for validation, development and discovery. We have developed a novel in-vivo chick embryo organ culture model systems which can be used for variety of mechanistic and biological studies to further understand the behavior of bone, bone repair and bone regeneration.

P. gingivalis, a red complex bacterium, has been associated with periodontitis. It has been studied extensively trying to understand the mechanism behind its virulence against the periodontium. Several investigations have studied the different virulence factors including Lipopolysaccharide (LPS), gingipain and fembriea. However, bone resorption mechanism that is caused by periodontitis is not fully understood. It is hypothesized that P. gingivalis virulence factors specifically LPS are behind bone resorption, not the bacterial cell itself. Therefore, we have tested this hypothesis and then further expanded on the results by adding Kavain that inhibit LPS-induced TNF-α in an attempt to rule out other virulence factor from bone resorption mechanism. Live neonatal mouse calvarial bone was utilized to carry out experiments in this project. We had five groups which included negative and positive control with parathyroid hormone (PTH) and PTH with Kavain and test groups with P. gingivalis supernatant with or without Kavain. These model systems were tested under resorption condition and evaluated by chemical, biochemical and histological analyses of the used media and calvarial bone. At the 8th day, calvaria from each experiments were analyzed by histology. TRAP and calcium release assays were also performed to further evaluate bone resorption and osteoclastic activity. We have found that when Kavain was added to the PTH, the calcium release and TRAP activity has reduced to half of the positive control without Kavain. P gingivalis supernatant alone showed uptake of calcium rather than release and adding Kavain increased the calcium uptake even more. However, TRAP activity were much higher than PTH group which does not coincide with the calcium release assay results. It seems that P. gingivalis LPS stimulated osteoclastic activity however it was not enough to result in bone resorption. It is thought that resorption and formation might be balanced and thus resorption was not observed. Further investigation is needed to study different doses of P. gingivalis supernatant on bone.

Oral health is an integral part of overall health. Oral health conditions, such as periodontal disease, can lead to lower quality of life. Periodontal disease is the inflammation of the tissue that surrounds the teeth. As this disease progresses, inflammation can affect the supporting bone around the teeth, creating pockets and eventually leading to tooth loss. With recent studies, serious systemic illness like cardiovascular disease, diabetes, and stroke have been linked to periodontal disease. Due to this association, maintaining a healthy oral cavity can help to prevent systemic disease. This interconnection of the mouth and body is just one of the many beliefs that holistic dentists possess. In holistic dentistry, dentists focus on proper nutrition, prevention of infection, and the use of nontoxic materials. Traditional dentistry is based on a problem-oriented model and often focuses on just the head and neck region. For years, traditional dentists have treated periodontal disease, but some treatments have led to negative outcomes. Conventional periodontal therapies have involved scaling and root planing, irrigation with antibiotic agents, as well as the administration of antibiotics, and invasive gum surgeries. In holistic dentistry, there are several noninvasive alternatives to treating periodontal disease. Such alternatives include a modified, safer approach to scaling and root planing, irrigation of ozone and other nontoxic agents, and laser therapy. In addition, holistic dentistry emphasizes the importance of disease prevention. Such practices include proper oral hygiene, incorporating supplementation to avoid vitamin deficiencies, and oral probiotics to promote a healthy oral microbiome. For patients suffering from periodontal disease, it may be beneficial to consider biocompatible periodontal therapy. This kind of therapy not only treats periodontal disease and addresses the cause of the problem while supporting the body’s natural healing process. Further research on holistic periodontal treatment, which has demonstrated success in a variety of studies, will continue to benefit both the oral cavity and overall wellbeing of patients.

It is known that anaerobic microbes like Porphyromonas gingivalis (P. gingivalis) are involved in the progression and initiation of multiple forms of periodontal disease such as chronic periodontitis. However, in order to culture this gram-negative anaerobic microbes in the laboratory we need a long time (about 72 hours) with a complete absence of oxygen (≤0.001%) to reach optimal cell density. Therefore it is usually treated in an anaerobic chamber. Because this traditional method to culture P. gingivalis is costly and time consuming, we tried to elaborate in this study a new, rapid and less expensive method for culturing the anaerobes, such as P. gingivalis and P. endodontalis. With the use of a rotary shaker under anaerobic conditions, it would seal the bacterial growth media from oxygen exposure using a mineral oil overlay. Additional analysis by western blot helped us to study more about the cell’s biological functions. As a result, we found that the RAW264.7 cells treated by P. gingivalis or P. endodontalis showed three groups of kinase phosphorylation levels. As these kinases are key factors for the bacteria induced inflammation, we are interested to find how to reduce such bacteria (i.e. P. gingivalis and P. endodontalis) induced inflammation via regulation of these related kinase phosphorylation in future studies. Based on our experiment, we believe that this method can be suitable for growing most species of anaerobic bacteria. Thus, we envision that this new method could be widely used in areas of both research and industry in the near future.

OBJECTIVE: To determine the link between the tumor necrosis factor induced protein 1(TNFAIP1) and TNF-alpha production in response to the P.gingivalis/LPS, and to investigate the mechanism that regulates the effect of the TNFAIP1 gene expression on TNF-alpha synthesis, using a new, simple, yet effective technique that allowed us to apply our methods on human macrophages. MATERIALS AND METHODS: We performed several experiments including: A culture of mouse RAW cells and human THP-1 cells in RPMI media supplemented with 10% FBS at 37°C in 5% CO2, Polymerase Chain reaction (PCR) using specifically designed primers and DNA cloning of TNFAIP1, transfection of the cloned TNFAIP1 cDNA into macrophages, Western blot analysis, ELISA analysis after treatment in macrophages, and GFP imaging system. RESULTS: 1. TNFAIP1 expression can reciprocally affect TNF-α production in macrophages. 2. Blocking MAPK, PI3K and JAK downregulates the TNF-alpha production. 3. The transfection of TNFAIP1 in THP-1 using a 1.5 ml Eppendorf tube generated a high transfection efficiency without the PMA treatment. 4. TNFAIP1 induces Caspase 1 gene expression in macrophages. 5. Caspase 1 induced by TNFAIP1 functions downregulation of TNF-alpha via p73. CONCLUSIONS: 1. MAP kinase, JAK, or PI3K, may be involved in TNF-α gene expression in LPS-dependent pathway. 2. TNFAIP1 expression can induce TNF-alpha production in mouse macrophages and vice versa. 3. TNFAIP1 gene expression in response to LPS is independent of NFkB-mediated signaling pathway. 4. The animal model has been confirmed by using both mouse macrophage-like cells (RAW cells) and a human macrophage-like cells (THP-1 cells). 5. The signaling pathway for the activation of TNF-alpha production in early stages is: LPS/ TNFAIP1/ PI3Kinase/AP-1/ TNF-alpha. 6. TNFAIP1 acts as a suppressor in later stage to down-regulate TNF-α gene expression via the following signaling pathway: LPS/TNF-alpha/ TNFAIP1/ Caspase 1/ Apoptotic genes/ Degradation of TNF-α/ Cell apoptosis. / 2020-05-23T00:00:00Z

OBJECTIVES: To compare the efficacy of fluoride varnishes for their ability to deliver fluoride and re-mineralize human enamel in vitro. METHODS: Three 5% NaF varnishes were used in this study: I. ProFluorid (VOCO), II. Vanish (3M ESPE), III. StarBright (Nanova Biomaterials) and IV. artificial saliva solution as a control. Twenty-four extracted intact adult teeth were randomly divided into 4 groups (n=12 per group). Each group was tested under two protocols (n=6 for each protocol). In Protocol A, artificial lesions were created by immersing the sound teeth in Coca Cola for 20 mins at 37 °C for demineralization (DM). Then a fluoridation step was performed by applying 3 mg of fluoride varnish as a thin layer (RM1). For the control group, artificial saliva was applied. All specimens were submerged in 30 mL of artificial saliva for 24 hr at 37°C. Following the treatment period, extra F varnish was removed from each specimen using chloroform moistened cotton swab and all teeth were then cleaned with deionized water for 10 seconds. The fluoridation cycle was repeated once more (RM2). For subgroups under Protocol B, tooth specimens with sound enamel were treated with two cycles of fluoridation (RM1 and RM2), then exposed to Coca Cola for 20 mins demineralization (DM). Surface micro-hardness of each tooth was measured at three random locations using Knoop hardness and fluoride content of each tooth was analyzed under (SEM/EDS) at baseline, after each fluoride varnish application, and demineralization treatment. The mean Knoop hardness and fluoride content by weight were calculated and the differences within treatment groups were analyzed by JMP Pro 13 using ANOVA. RESULTS: The application of all fluoride varnishes significantly increased the fluoride content of the lesioned enamel (p<0.05). ProFluorid varnish had increased the enamel surface hardness significantly compared to the other two varnishes (StarBright and Vanish), and the difference was statistically significant (p < 0.05). CONCLUSIONS: This study concludes that application of NaF varnish twice can significantly increase the fluoride content in enamel in both remineralization and protection cases, However, the twice application would increase surface hardness of enamel in artificial caries protocol only.