Desmoplastic fibroblastoma (collagenous fibroma) on the mandibular ridge: case report and review of immunohistochemical markers

The desmoplastic fibroblastoma (DF) is a rare benign soft-tissue tumor of fibroblastic and myofibroblastic origin, and its occurrence in the oral cavity is rare. This study details a new case of an elevated lesion in the alveolar ridge of a 59-year-old woman, painful during mastication. The histopathological exam showed non-encapsulated stellate-to-spindle cells proliferation in a hypocellular collagen-rich stroma. Tumor cells were strongly and diffusely positive for vimentin, and some cells were focally positive for α-smooth muscle actin, CD99, and β-catenin. The exams were conclusive for DF diagnosis. The patient is in the follow-up period, and no recurrent lesions were detected within one year. Despite having similar clinical, pathological, and immunohistochemical features to the cases previously described, the DF in this report is at an unusual oral site and associated with painful symptomatology. Immunohistochemistry is an important tool in DF cases where the histopathological examination is not conclusive.

Hedgehog signaling controls mouth opening in the amphioxus

Introduction The left-sided position of the mouth in amphioxus larvae has fascinated researchers for a long time. Despite the fundamental importance of mouth development in the amphioxus, the molecular regulation of its development is almost unknown. In our previous study, we showed that Hh mutation in the amphioxus leads to no mouth opening, indicating a requirement of Hh signaling for amphioxus mouth formation. Nevertheless, since the Hh mutant also exhibits defects in early left-right (LR) patterning, it remains currently unknown whether the loss of mouth opening is affected directly by Hh deficiency or a secondary effect of its influence on LR establishment. Results We demonstrated that knockout of the Smo gene, another key component of the Hh signaling pathway, in the amphioxus resulted in the absence of mouth opening, but caused no effects on LR asymmetry development. Upregulation of Hh signaling led to a dramatic increase in mouth size. The inability of Smo mutation to affect LR development is due to Smo’s high maternal expression in amphioxus eggs and cleavage-stage embryos. In Smo mutants, Pou4 and Pax2/5/8 expression at the primordial oral site is not altered before mouth opening. Conclusions Based on these results and our previous study, we conclude that Hh signal is necessary for amphioxus mouth formation and that the Hh-mediated regulation of mouth development is specific to the mouth. Our data suggest that Hh signaling regulates mouth formation in the amphioxus in a similar way as that in vertebrates, indicating the conserved role of Hh signaling in mouth formation.

Molecular Screening and Analysis Reveal Novel Oral Site-Specific Locations for the Cariogenic Pathogen Scardovia wiggsiae

Introduction: Scardovia wiggsiae (SW) is a newly identified cariogenic pathogen associated with severe early childhood caries and oral disease. New studies have confirmed the presence of this organism among clinical samples from both pediatric and adult patients. However, the recent discovery of this organism has left researchers with only limited information available regarding the prevalence of this organism—and virtually no information regarding oral site-specific locations. Based upon this lack of information, the overall objective of this study was to perform an oral site-specific analysis of SW prevalence from clinical samples. Methods: Using an approved human subjects protocol, samples (n = 60) from an existing saliva and site-specific biorepository were identified and screened for SW presence using quantitative polymerase chain reaction (qPCR). These data were summarized and subsequently analyzed for correlations with demographic (age, sex, race or ethnicity) or clinical (body mass index or BMI, primary/mixed/permanent dentition, orthodontic brackets) variables. Results: These data revealed that average DNA concentrations from all sample sites (saliva, dorsum of tongue, gingival crevicular fluid (GCF), biofilm of upper buccal molar, and biofilm of lower lingual incisor) ranged between 13.74 and 14.69 μg/μL, with an overall average of 14.30 μg/μL ± 1.12 (standard error or SE). qPCR screening revealed a total of n = 34/60 or 56.7% of patient samples harboring SW. A total of n = 71/170 specific oral sites harbored this organism, with the majority of the SW-positive participant samples harboring SW at more than one oral site, n = 22/34 or 64.7%, including non-traditional sites such as GCF and the dorsum of the tongue. Weak correlations were found between specific SW outcomes in GCF and type of dentition (permanent; R = 0.2444), as well as SW outcomes in saliva with age (R = 0.228) and presence of orthodontic brackets (R = 0.2118). Conclusions: This study may be among the first to provide oral site-specific analysis to reveal the prevalence and location of Scardovia among clinical patient samples. Moreover, these data also provide some of the first evidence to suggest this organism may be present not only in traditional supragingival tooth-associated biofilm sites, but also in non-traditional oral sites including the dorsum of the tongue and the gingival crevice. Based upon these results, these data may represent a significant advance in our understanding of the potential sites and locations that harbor this organism and may help contribute to our understanding of the prevalence, distribution and potential for the development of oral disease among clinic patients.

Microbial Screening Reveals Oral Site-Specific Locations of the Periodontal Pathogen Selenomonas noxia

Introduction: Selenomonas noxia (SN) is an important periodontal pathogen, associated with gingivitis and periodontitis. Many studies have found associations between SN and indicators of poor health outcomes, such as smoking, low socioeconomic status and obesity. However, less is known about the prevalence of this organism and more specifically about other oral site-specific locations that may harbor this organism. Methods: Using an existing patient repository (n = 47) of DNA isolated from saliva and other oral sites (n = 235), including the dorsum of the tongue, lower lingual incisor, upper buccal molar and gingival crevicular fluid (GCF), molecular screening for SN was performed. Screening results were analyzed for associations between demographic variables (age, sex, race/ethnicity) and clinical information (body mass index or BMI, presence of orthodontic brackets, primary/mixed/permanent dentition). Results: qPCR screening revealed a total of n = 62/235 sites or 26.3% harboring SN with saliva and GCF (either alone or in combination with one or more sites) most often observed (Saliva, n = 23/27 or 85.18%, GCF, n = 14/27 or 51%). Analysis of site-specific data revealed most positive results were found among saliva and GCF alone or in combination, with fewer positive results observed among the tongue (33.3%), lower lingual incisor (29.6%), and upper buccal molar (25.9%). No significant associations were found between demographic or clinical variables and presence of SN at any site. Conclusions: These results may be among the first to describe site-specific locations of S. noxia among various additional oral biofilm sites. These data may represent a significant advancement in our understanding of the sites and locations that harbor this organism, which may be important for our understanding of the prevalence and distribution of these organisms among patients of different ages undergoing different types of oral treatments, such as orthodontic treatment or therapy.

Ecological Perturbations Impact Species-Specific Gene Expression of the Oral Microbiota

Background: The purpose of the present investigation was to use the oral cavity as an in-vivo model to study the impact of internal and external perturbations on bacterial biofilm communities. We tested the hypotheses that bacterial gene expression of the healthy microbiota reflects habituation to site-specific ecological perturbations, and that the perturbation effect of chronic inflammation, i.e. periodontitis, impacts bacterial gene expression not only locally, but also at other sites of the oral cavity. Oral microbial samples were collected from three oral sites – plaque, tongue and saliva from patients with periodontitis and healthy controls. Paired metagenomics and metatranscriptomics were used to perform concomitant characterization of taxonomic composition and to determine species specific bacterial activity as expressed by the ratio of messenger RNA to the corresponding genomic DNA.Results: Here we show the impact of two perturbations – oral site and periodontitis - on bacterial gene expression of the oral microbiota. The oral site was the main determinant of taxonomic composition as well as bacterial gene expression. However, bacterial activity at the three oral sites (plaque, tongue, and saliva) was significantly impacted by periodontitis, with a reduction of the carbohydrate metabolism.Conclusions: Data from the present study characterize the impact of two perturbations – oral site and periodontitis - on bacterial gene expression of the oral microbiota. The oral site was the main determinant of taxonomic composition as well as bacterial gene expression. However, presence of periodontitis had impact on bacterial activity of both plaque but also on tongue and the salivary microbiota. Collectively, data suggest that periodontitis associates with impaired carbohydrate metabolism of the oral microbiota. Future longitudinal and interventional studies are warranted to evaluate the potential pathogenic role of impaired bacterial carbohydrate metabolism not only in periodontitis, but also in other diseases with low grade inflammation, such as type 2 diabetes mellitus.

Oral Site Specific Sampling Reveals Differential Location for Scardovia wiggsiae

Introduction: The newly discovered cariogenic pathogen Scardovia wiggsiae has been the subject of intense scientific interest due to the role it may play in the development or progression of caries and oral disease. The primary objective of this study was to perform DNA microbial screening from five specific oral sites, including the gingival crevice between the upper central incisors, biofilm of the upper first molar and lingual incisor, as well as the dorsum of the tongue – for comparison with unstimulated saliva. These data may provide significant insights into site-specific oral locations that harbor S. wiggsiae. Methods: More than one hundred previously collected clinical samples (n=105) were identified for inclusion in this study. DNA isolates were screened using a NanoDrop spectrophotometer to determine overall DNA quantity and quality. Samples with sufficient quality and quantity were screened for the presence of S. wiggsiae using validated PCR primers. Results: More than one hundred patient samples (n=105) were identified, which were comprised of mostly female (57%) versus male (43%) and minority (71%) versus White (29%). The average DNA concentrations ranged between 13.74 and 14.69 mg/mL, with A260:A280 ratios ranging between 1.62 – 1.70. Results of molecular screening using S. wiggsiae specific primers demonstrated only a small percentage of pooled samples (7.6%) harbored this DNA, which was highly concentrated among the samples from tooth surfaces (Upper First Molar, Lingual Incisor) and saliva compared with the gingival crevice and dorsum of the tongue. Discussion: These data provide novel information regarding specific oral locations, including tooth surfaces that harbor S. wiggsiae. In addition, these sites also provide new information regarding oral sites that do not appear to harbor this organism, including the gingival crevice and dorsum of the tongue. This information may be particularly useful to oral health researchers as they strive to limit and reduce the cariogenic microbiome among high-risk populations.

Oral Microbiota Composition and Antimicrobial Antibody Response in Patients with Recurrent Aphthous Stomatitis

Recurrent aphthous stomatitis (RAS) is the most common disease of the oral mucosa, and it has been recently associated with bacterial and fungal dysbiosis. To study this link further, we investigated microbial shifts during RAS manifestation at an ulcer site, in its surroundings, and at an unaffected site, compared with healed mucosa in RAS patients and healthy controls. We sampled microbes from five distinct sites in the oral cavity. The one site with the most pronounced differences in microbial alpha and beta diversity between RAS patients and healthy controls was the lower labial mucosa. Detailed analysis of this particular oral site revealed strict association of the genus Selenomonas with healed mucosa of RAS patients, whereas the class Clostridia and genera Lachnoanaerobaculum, Cardiobacterium, Leptotrichia, and Fusobacterium were associated with the presence of an active ulcer. Furthermore, active ulcers were dominated by Malassezia, which were negatively correlated with Streptococcus and Haemophilus and positively correlated with Porphyromonas species. In addition, RAS patients showed increased serum levels of IgG against Mogibacterium timidum compared with healthy controls. Our study demonstrates that the composition of bacteria and fungi colonizing healthy oral mucosa is changed in active RAS ulcers, and that this alteration persists to some extent even after the ulcer is healed.

Diode laser assisted excision of a gingival pyogenic granuloma: A case report

exuberant, reactive lesion seen in response to local irritation or trauma caused by dental calculus, bacterial plaque, caries and restorations, with a strong predilection for the gingiva. It is among the frequently encountered oral lesions, occurring at a challenging oral site, the gingiva. Herein, we report a 71-year-old medically compromised Caucasian female who presented with a relatively large lobulated pyogenic granuloma on the buccal gingiva of the maxillary molar-premolar region. Total surgical excision was performed with an 840nm diode laser followed by the placement of hyaluronate gel and relevant periodontal dressing. Two weeks after surgical excision, complete healing was observed, but patient denied replacement of dental restoration. After 4 months of follow-up, an overall reduction of associated teeth mobility was also observed, with a minor recurrence in gingival inflammation. The objective of this report is to briefly review clinical, radiographic and histological findings of pyogenic granuloma along with a detailed discussion on its management through a diode laser.

Comparison of Two Routes of Administration of Dexamethasone to Reduce the Postoperative Sequelae After Third Molar Surgery: A Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to compare the clinical efficacy of two routes of dexamethasone administration in reducing the postoperative sequelae after third molar extraction. Electronic databases (PUBMED, SCOPUS and EBSCO library) were screened in order to find both randomized and non-randomized clinical trials that directly compare the submucosal intraoral or the intramuscular extraoral administration of dexamethasone. No restriction about year of publication was imposed. About 340 titles and abstracts were screened independently by two authors. Of these [340 titles], only 4 randomized clinical trials met the inclusion criteria and were included in the meta-analysis. No statistical differences in postoperative pain, swelling and trismus were recorded comparing the intraoral submucosal and the extraoral intramuscular injection of dexamethasone in an extra-oral site.