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Candida albicans is an oral mucosal commensal fungus that transforms into an opportunistic pathogen under specific conditions, including immunosuppression. It causes oral and systemic candidiasis, which results in a significant health burden. Furthermore, an alarming rise in antifungal drug resistance in Candida species raises the urgent need for novel drugs and drug targets. C. albicans Dfg5 and Dcw1 are homologous cell wall alpha-1,6-mannosidases with critical functions and represent potential new drug targets. Our past studies have shown that Dfg5 and Dcw1 function in cell wall biogenesis through the cross-linking of glycoproteins into the cell wall, thus playing a key role in cell wall integrity. Additionally, Dfg5 and Dcw1 are required for hyphal morphogenesis. However, the exact functions of Dfg5 and Dcw1 in cell wall integrity, hyphal morphogenesis, and pathogenesis are not known. In this study, we determined the relation of Dfg5 and Dcw1 with Hog1 MAPK, which plays a key role in cell wall integrity via the regulation of chitin synthesis in C. albicans. Additionally, we also determined the effects of dfg5 and dcw1 mutations on the gene expression of transcriptional regulators of hyphal morphogenesis. Furthermore, we determined the effects of dfg5 and dcw1 mutations on pathogenesis in a mouse model of oral candidiasis. Our results demonstrate that dfg5 and dcw1 mutations, as well as a hog1 knockout mutation, result in the dysregulation of chitin synthesis, resulting in a cell separation defect. Heterozygous and conditional mutations in dfg5 and dcw1 resulted in decreased transcriptional levels of cst20, a positive regulator of hyphal morphogenesis. However, dfg5 and dcw1 mutations resulted in increased levels of all the five negative regulators of hyphal morphogenesis—Tup1, Nrg1, Mig1, Rbf1, and Rfg1. Additionally, Tup1 levels were significantly higher than other negative regulators, indicating that Dfg5 and Dcw1 function in hyphal morphogenesis by repressing Tup1. Finally, dfg5 and dcw1 mutations affected the ability of C. albicans to cause oral candidiasis in mice. Thus, the cell wall glycosidases Dfg5 and Dcw1 are required for virulence and pathogenesis and represent novel drug targets. [ABSTRACT FROM AUTHOR]

Periodontal disease has been associated with various systemic diseases including kidney disease. However, a causal relationship is yet to be established. One possible association is that periodontitis may cause an increased inflammatory response in kidney disease patients which in turn destroys endothelial vasculature. This may contribute to development of risk factors of kidney disease such as diabetic neuropathy and cardiovascular events leading the progression and mortality in kidney disease patients. The role of periodontal inflammation driving kidney disease is still under investigation. This review article highlights the role of periodontal inflammation in the development and progression of kidney disease. It is crucial that dental practitioners and nephrologists understand the association between periodontal and kidney disease. Early periodontal screening and educating patients about the importance of good oral hygiene may play an important role in prevention of progression of kidney disease. [ABSTRACT FROM AUTHOR]

Flapless approach to implant surgery is emerging as a viable alternative to traditional implant surgery, where a full-thickness flap is raised and the alveolar bone is exposed for placement of dental implants. However, there are several disadvantages of the traditional approach, including patient morbidity, bleeding and postoperative complications. With the advent of digital technologies, such as cone beam computed tomography (CBCT) and 3D printing of surgical guides, flapless surgery has become desirable for implant placement, especially for general dentists. This manuscript discusses the benefits and risks of the flapless approach as compared to the traditional approach for dental implant placement and describes a step-by-step approach to flapless implant placement. [ABSTRACT FROM AUTHOR]

Narrow diameter implants and mini-implants are preferred by dentists for restoration of missing teeth on narrow ridges. However, such implants are associated with long-term complications, including softimtissue deficiencies. This case report describes a novel approach using a connective-tissue graft to resolve peri-implant mucositis. A 66-year-old male patient presented with infiammation and abscess in relation Unito a mini-implant at the upper left incisor on the facial aspect. Deficiencies of keratinized tissue and width of attached gingiva were observed. Surgical management was performed using subepithelial connective tissue. An 18-month follow-up showed increased width of attached gingiva at the surgical site. [ABSTRACT FROM AUTHOR]

Background: A cross-sectional study was conducted among intensive care unit (ICU) nurses in private hospitals in India to identify knowledge and practice of ICU nurses in the prevention of ventilator-associated pneumonia (VAP).Methods: Knowledge of 135 nurses working in ICU was tested using a questionnaire consisting of 18 questions. Fourteen forms were excluded from the statistical analysis due to incomplete data entry by the participants. The data of 121 filled questionnaires were analyzed. The information letters, consent forms, and questionnaires were handed to ICU nurses by Research assistant. Data were coded and entered into SPSS version for descriptive and inferential statistics.Results: A majority of the participants perceived oral care as a necessity in all critically ill patients. Nurses were generally aware of the most likely mechanism of acquiring pneumonia. The type and frequency of oral care varied widely. Many of them stated that they had adequate supplies to provide oral care. Although a majority of nurses had some formal training in oral care, they would appreciate an opportunity to enhance and improve their knowledge and skills.Conclusion: The methods of oral care provided vary widely. In summary, randomized controlled trial to date has demonstrated that tooth brushing is associated with a trend toward lower rates of VAP in intubated mechanically ventilated critically ill patients. But it is also to be noted that there was no clear difference between electric and manual tooth brushing. In-house training and workshop can provide required skills needed for the betterment of the treatment provided. [ABSTRACT FROM AUTHOR]

Background and Objectives. Studies of gum or periodontal disease have focused mainly on bacterial pathogens. However, information related to fungal species in the saliva and subgingival mileu is particularly lacking in smokers with periodontitis. This cross-sectional study compared the prevalence of various Candida species in saliva and subgingival plaque samples of smokers and non-smokers with periodontal disease. Methodology. Study subjects were recruited into three group--Group 1: Smokers with chronic periodontitis (N = 30), Group 2: Non-smokers with chronic periodontitis (N = 30) and Group 3: Healthy controls (N = 30). Clinical parameters recorded included plaque index (PI), gingival index (GI), periodontal probing depth (PPD) and clinical attachment loss (CAL). Saliva and subgingival plaque samples were collected from subjects from the above groups. The collected samples were processed for isolation and identification of various Candida species using CHROMagar chromogenic media. Additionally, antifungal susceptibility tests were performed for the isolated Candida species in order to assess antifungal drug resistance to fluconazole and voriconazole. Results. Prevalence of Candida species in saliva samples was quantified as 76.6% in Group 1, 73.3% in Group 2 and 36.6% in Group 3 and statistically significant differences were observed between groups 1 & 3. Prevalence of Candida species in subgingival plaque samples was quantified as 73.3% in Group 1, 66.6% in Group 2 and 60% in Group 3 and no statistically significant differences were observed between groups. Candida albicans was the most frequently isolated species followed by Candida krusei and Candida tropicalis. A positive correlation was observed for smoking exposure, pack years and Candida colonization. A marginally significant positive correlation was observed between Candida colonization and increasing pocket depth and attachment loss. Antifungal drug resistance was mainly observed for Candida krusei in both saliva and subgingival plaque samples. Conclusion. Based on the results we can conclude that oral candidal carriage is significantly increased in smokers with periodontal disease. Mechanistic studies are needed to understand the importance of Candida species in periodontal disease. [ABSTRACT FROM AUTHOR]

Polymicrobial biofilms play important roles in oral and systemic infections. The oral plaque bacterium Streptococcus gordonii is known to attach to the hyphal cell wall of the fungus Candida albicans to form corn-cob like structures in biofilms. However, the role of C. albicans in formation of polymicrobial biofilms is not completely understood. The objective of this study was to determine the role of C. albicans transcription factors in regulation of polymicrobial biofilms and antibiotic tolerance of S. gordonii. The proteins secreted by C. albicans and S. gordonii in mixed planktonic cultures were determined using mass spectrometry. Antibiotic tolerance of S. gordonii to ampicillin and erythromycin was determined in mixed cultures and mixed biofilms with C. albicans. Additionally, biofilm formation of S. gordonii with C. albicans knock-out mutants of 45 transcription factors that affect cell wall integrity, filamentous growth and biofilm formation was determined. Furthermore, these mutants were also screened for antibiotic tolerance in mixed biofilms with S. gordonii. Analysis of secreted proteomes resulted in the identification of proteins being secreted exclusively in mixed cultures. Antibiotic testing showed that S. gordonii had significantly increased survival in mixed planktonic cultures with antibiotics as compared to single cultures. C. albicans mutants of transcription factors Sfl2, Brg1, Leu3, Cas5, Cta4, Tec1, Tup1, Rim101 and Efg1 were significantly affected in mixed biofilm formation. Also mixed biofilms of S. gordonii with mutants of C. albicans transcription factors, Tec1 and Sfl2, had significantly reduced antibiotic tolerance as compared to control cultures. Our data indicates that C. albicans may have an important role in mixed biofilm formation as well as antibiotic tolerance of S. gordonii in polymicrobial biofilms. C. albicans may play a facilitating role than being just an innocent bystander in oral biofilms and infections. [ABSTRACT FROM AUTHOR]

Background. Candida albicans is a commensal fungus that inhabits the oral mucosal surface and causes oral and systemic candidiasis. Oral candidiasis most commonly occurs in patients with AIDS, denture wearers and newborn children. Systemic candidiasis occurs mainly in immunocompromised patients and patients admitted to hospitals for prolonged periods. C. albicans homologous genes, DFG5 and DCW1, encode for two closely related cell wall proteins with putative glycosyltransferase enzyme activity and C-terminal GPI-anchors. Past studies have shown that individual DFG5 and DCW1 mutations are viable but simultaneous deletion of DFG5 and DCW1 in C. albicans results in lethality. However, the exact functions of these cell wall based enzymes, which represent potential drug targets, are not understood. Methods. C. albicans DFG5/DCW1 heterologous and conditional double mutant strains were assessed for growth and biofilm formation in comparison to wild type and parental strains. Cell wall and heat stress susceptibility of the mutant and control strains were assessed using agar spotting assays. Growth was assessed under normal and osmotic stress conditions along with light microscopy imaging. Biofilm dry weight and microscopic imaging analysis of biofilms was performed. Hypha formation in response to serum was analyzed using light microscopy imaging. Western blot analysis of mutant strains and control strains was performed to assess Hog1 basal levels and phosphorylation status. Results. Analysis of the heterologous mutants indicated that Dfg5p is more important for growth while Dcw1p appeared to play a role in cell wall integrity response. The conditional double mutant was observed to be less resistant to cell wall stress. However, growth of the mutants was similar under control and osmotic stress conditions. The mutants were also able to grow similar to wild type under heat stress. Biofilm formation was reduced in the mutants where DFG5 was deleted or suppressed. Hyphal morphogenesis was reduced although germ tube formation was observed in the biofilms of the mutant strains. Basal Hog1 protein levels were reduced or absent in the DFG5 and DCW1 mutants. However, osmotic stress was able to induce Hog1 protein levels comparable to wild type. Hog1 phosphorylation appeared to be slightly reduced although not significantly. In addition to biofilm assays, serum dose response imaging analysis indicated that hyphae formation in DFG5 and DCW1 mutants was defective. Conclusions. These data indicate that DFG5 and DCW1 are required for hyphal morphogenesis and biofilm formation in C. albicans. These functions may be regulated via basal Hog1 MAPK which is required for transcriptional regulation of chitin synthesis. [ABSTRACT FROM AUTHOR]

We report a case of localized aggressive periodontitis (LAP), which occurred during fixed orthodontic treatment in a 16-year-old African-American female patient. Oral hygiene instruction, removal of orthodontic bands and nonsurgical periodontal therapy were followed by surgical treatment of multiple sites using calcium sulfate as a synthetic bone graft material and collagen membrane as a barrier to achieve guided tissue regeneration. One-year follow-up of the case demonstrated that use of calcium sulfate as a synthetic bone substitute may provide favorable outcome in LAP patients. Furthermore, LAP patients undergoing orthodontic treatment can be managed successfully without tooth morbidity. [ABSTRACT FROM AUTHOR]

Dental implants are being increasingly used in dentistry. Millions of implants are being placed on a yearly basis around the world by dental surgeons. These implants support restorations ranging from a single crown to a denture. There are significant costs associated with implant supported restorations. The advent of peri-implant diseases threatens the survival and maintenance of implant supported restorations leading to significant impact on the sustainability of such restorations while affecting the patient's functionality. This review article discusses the current concepts, as well as the etiopathological and treatment considerations related to peri-implant diseases. [ABSTRACT FROM AUTHOR]

Purpose: Oral biofilms harbor several hundreds of species of bacteria as well as spirochetes, protozoa, fungi and viruses. The composition of the oral biofilm varies from health to disease. It is the source of microorganisms that cause dental and periodontal infections. Oral infections and periodontal disease have been implicated in the etiopathogenesis of several important chronic systemic diseases. [ABSTRACT FROM AUTHOR]