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Background: Craniofacial morphogenesis is the result of an intricate multistep network of tightly controlled spatial and temporal signalling that involves several molecules and transcription factors organized into highly coordinated pathways. Any alteration in even one step of this delicate process can lead to congenital malformations such as cleft palate. One of the first steps in embryonal orofacial development is the migration of cells from the neural crests to the branchial arches. Next, the cells have to proliferate, differentiate, move and connect to each other in order to correctly form the palate. Cell contraction, promoted by the interaction of non-muscle myosin II and actin A, is a crucial step in morphogenesis and is regulated by ROCK1 protein. Methods: A family-based association study was carried out in order to verify whether or not genetic variants of ROCK1 were associated with non-syndromic cleft palate (nsCP). Two cohorts from Italy and Iran, a total of 189 nsCP cases and their parents were enrolled. Results: The rs35996865-G allele was under-transmitted in cases of nsCP [P =.006, odds ratio (OR) = 0.63 (95% CI 0.45-0.88)]. Conclusion: This investigation reveals for the first time data supporting a role for ROCK1 in nsCP aetiology.

Diagnosis of focal disease, the theory that the human oral microbial (HOM) could affect the onset and development of systemic diseases, was very popular in the past, but the lack of scientific evidence has led to the abandonment of this idea. Interestingly, increasing evidence over the past 3 or so decades suggests that HOM can indeed serve as a reservoir for systemic dissemination of pathogenic bacteria and their toxins in distant body sites, favouring the developments of malignant tumours. Malignant tumours are complex communities of oncogenically transformed cells with aberrant genomes, associated nonneoplastic cells including immune and stromal cells, and sometimes HOM, including bacteria and viruses. Recent data suggest that HOM and periodontal disease play an active role in the pathogenesis of colorectal cancer, in fact HOM has been found within the colorectal cancer microenvironment, and the composition of the HOM was different from that of adjacent non- neoplastic tissue. An association of fusobacterium nucleatum with the colonic mucosa of colorectal cancer has been proven. Several questions thus arise. Is periodontal disease a risk factor for colorectal carcinoma? Given the connectivity of the digestive tract, could fusubacterium nucleatum or other HOM be involved in additional gastrointestinal disorders? Furthermore, based on the “mobility” of Fusubacterium nucleatum and the omnipresence of cadherins, could this organism be involved in cancers beyond the gastrointestinal tract? Answers to these questions will shed new lights on the role of the HOM in onset of diseases.

Gabapentin is one of the most used drugs to treat postoperative pain with antihyperalgesic properties and has a unique mechanism of action, which differentiates it from other commonly used drugs. Various studies have shown that the perioperative use of gabapentin reduces postoperative pain. In our study, fragments of gingival tissue of healthy volunteers were collected during operation. Gene expression of 29 genes was investigated in gingival fibroblasts cell culture treated with gabapentin, compared with untreated cells. Of the different chemokines and interleukins studied, only 10 were statistically significant (CCL1, CCR1, CCR4, CCR5, CCR6, ILI1A, ILI1B, IL5, IL6R, TNFSF10). The overexpression of these cytokines, obtained in many studies, leads us to think that gabapentin can interact and cause post-inflammatory gingival hyperplasia, but, probably, in our study the gabapentin has not the same effect, because we used gingival fibroblasts of healthy people.

Periodontal disease (PD) is one of the prevalent diseases in the adult population. The ethiology of PD has never been completely understood, however, loss of balance between the host immune system and the microbial virulence of PD pathogens may be considered the trigger of PD. In fact, the immune system, activated by microbiological agents, attacks the host and not the biofilm bacteria, causing the destruction of periodontal tissue, alveolar bone and loss of teeth. Parasites may play an important role in the pathology of PD. The first studied and the most common parasite in the oral cavity is Entamoeba gingivalis. A possible link between E. gingivalis and PD has never been demonstrated completely, however E. gingivalis is infrequently found in people without PD. In addition, there is evidence that E. gingivalis could favour the onset and progression of PD. In conclusion, we can assert that E. gingivalis and PD may be correlated. This relationship can open new therapeutical approaches for treating PD, particularly in cases refractory to therapy.

Legionella spp. are ubiquitous in aquatic habitats and water distribution systems, including dental unit waterlines. Surveys have shown that the percentage of samples taken at different dental sites that were positive for Legionella spp. was highly variable and ranged from 0% to 100%. Cultivation is the principal approach to evaluating bacterial contamination employed in the past, but applying this approach to testing for Legionella spp. may result in false-negative data or underestimated bacterial counts. PCR and direct fluorescent counts can detect viable non-cultivable bacteria, which are not counted by plating procedures. Legionella spp., commonly form such viable non-culturable cells and it is likely that they contribute to the difference between plate count results and those of PCR and fluorescent-antibody detection. However, studies have shown that Legionella is present in the municipal water source in spite of the current filtration and chlorination procedures. Once Legionella reaches the building water system, it settles down into a biofilm layer of stagnant water. By means of this layer, Legionella can protect itself from antimicrobial agents and then multiply. Dental unit waterlines may be contaminated with opportunistic bacteria. The water quality in the dental units should be controlled to eliminate opportunistic pathogens and to provide water for dental treatment that meets public health standards for potable water.

Periodontitis is a multifactorial disease that, if untreated, may cause teeth loss. Clinicians and researchers have reported that genetic factors influence the clinical manifestations of periodontal disease (PD), modulating both inflammation of the mucous membranes and loss of alveolar bone. The acquisition of new knowledge about genetic susceptibility of PD, would directly impact on prognosis and treatment of the disease. In addition, a better understanding of PD pathogenesis could improve the diagnostic tools for the prevention, and therapies for modulation of immune responses and treatment of PD. In this study, we evaluated genetic polymorphisms of VRD, IL6 and IL10 and amounts of periodontal pathogens in Italian adults affected by PD. We included 326 cases classified according the criteria of the American Academy of Periodontology. No significant differences in bacterial load were found in patients carrying PD susceptibility alleles of IL6, IL10 and VDR genes. In conclusion, no interaction between genetic factors and amount of periodontal pathogens in periodontal pockets were found in PD patients.

Gingivitis and periodontitis are the two main periodontal diseases. Both are characterized by inflammation of the tissues surrounding the teeth but while tissue damages observed in gingivitis are mild and reversible, destruction caused by periodontitis is deeper and irreversible. Periodontal diseases and levels of degeneration of tissues surrounding teeth depend on several interacting endogenous and exogenous factors. Polymorphisms of genes encoding molecules that modulate the immune response and tissue homeostasis are the main causes of individual susceptibility to periodontal diseases. The aim of this study was to investigate IL6, IL10 and VDR gene polymorphisms in a large number of subjects affected by either gingivitis or chronic periodontitis. The sample included 750 Italian patients. We found that the rs1800795 SNP located in the IL6 gene promoter was strongly associated with the occurrence of both gingivitis and periodontitis. Indeed, homozygous individuals with variant allele appeared less-susceptible to both gingivitis OR=0.47 (95% C.I. 0.27-0.82) and periodontitis OR=0.36 (95% C.I. 0.21-0.64). No evidence of association between periodontal diseases and IL10 or VDR polymorphisms was obtained. This data confirmed the role of IL6 in susceptibility to periodontitis among the Italian population. The evidence that IL6 polymorphisms are also involved in gingivitis has implications in periodontal disease pathogenesis and reduces the appeal of IL6 as a periodontitis biomarker.

Introduction: About 30% of the general population manifests periodontal disease (PD). Patients with parents with a compromised periodontal condition may need prosthetic or implantology treatment (PIT), therefore those patients are at increased risk of developing PD during or after dental treatment. Hence the use of a genetic test for identify those most at risk of PD and submit them to very closely oral hygiene protocols, is mandatory. PIT of these patients must be done safely having previously assessed the risk of developing PD. Polymorphisms of IL6 and IL10 constitute risk factors for chronic periodontitis, so the use of a genetic test is fundamental to ensure a correct preventive protocol and plaque control in healthy patients.

Periodontal tissues surround the teeth and provide their attachment. Periodontal diseases include a mild and reversible form named gingivitis, and periodontitis that is the main cause of tooth loss in adults. Gingivitis, that affects gums and coronal junctional epithelium, as well as periodontitis, that is characterized by loss of connective tissue attachment, are caused by a persistent inflammatory response promoted by alteration of periodontal biofilm. The aim of the study was to test whether the prevalence or relative amount of each species was associated with a particular clinical condition. Periodontal evaluation of 539 unrelated patients was performed by the Periodontal Screening and Recording (PSR) system. Subgingival samples were obtained from the site with the worst PSR score. A selection of eleven bacterial species was evaluated by quantitative real time PCR. Some bacterial species were found to be associated with all phases of periodontal disease, such as Tannerella forsythia, Treponema denticola, and Treponema lecithinolyticum, while other species were more specifically associated with periodontitis, such as Porphyromonas endodontalis and Porphyromonas gingivalis, or with gingivitis, such as Capnocytophaga ochracea and Campylobacter rectus. Quantitative and qualitative analyses helps to better understand the microbial changes associated with different stages of periodontal disease.

Dental pulp stem cells (DPSCs) are multipotent stem cells with the potential to differentiate into various cell types. For this reason, they have been proposed as an alternative source for mesenchymal stem cells. Somatostatin is a peptide hormone with an inhibitory effect on several endogenous hormones. The aim of our study is to investigate whether somatostatin can promote or inhibit differentiation of DPSCs in osteoblasts and bone tissue. DPSCs were extracted from third molars of healthy subjects, and were treated with somatostatin at the concentration of 100 ng/ml for 24 and 48 h. Gene expression in treated DPSCs was compared with untreated cells (control) in order to check the effect of somatostatin on stem cell differentiation. After 24 h of treatment many genes investigated were down-regulated in treated DPSCs vs untreated DPSCs. Significantly up-regulated gene (Fold change > 2) was the Bone Morphogenetic Protein BMP4. On the contrary somatostatin induced the over-expression of bone related genes after 48 h of treatment (i.e. BMPR1B and BMPR2). TGFB family genes and their receptors were also significantly up-regulated after 48 h of treatment. Somatostatin demonstrated to promote the self-renewal of DPSCs: in our experiments somatostatin mainly acted on TGFB family genes. Further studies are needed to explore this new way of creating bone tissue.

Periodontitis is a disease that affects and destroys the tissues that support teeth. Tissues damage results from a prolonged inflammatory response to an ecological shift in the composition of subgingival biofilms. Three bacterial species that constitute the red complex group, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, are considered the main pathogens involved in periodontitis. In the present study a real-time PCR based assay was designed to detect and quantify red complex species, then used to investigate 146 periodontal pocket samples from 66 periodontitis patients and 80 controls. Results demonstrated a significant higher prevalence of red complex species and increased amount of P. gingivalis and T. denticola in periodontal pocket of periodontitis patients.

Apical extrusion of infected debris to the periradicular tissues is considered one of the possible factors related to the occurrence of postoperative pain and inflammation. The goal of the present study is to evaluate and compare the incidence and intensity of postoperative pain using two different nickel-titanium instrumentation techniques: a rotary crown-down technique using TF instruments ( SybronEndo, Orange, Ca, USA) and a reciprocating single-file technique using Reciproc instruments (VDW, Munich, Germany). Sixty patients requiring endodontic treatment on permanent premolar and molar teeth with non-vital pulps preoperatively were included in the study. The patients were divided into two groups of 30 patients each, trying to make the groups very similar, concerning the number of root canals, presence of initial pain and periapical lesions. The teeth in group 1 (n = 30) were treated with a crown-down technique using TF instruments whilst those in group 2 (n = 30) were treated with a single-file technique using Reciproc 08 25. All canals were shaped, cleaned and obturated in a single-visit. The assessment of postoperative pain was carried out at 3 days by using a visual analogue scale. Chi-square tests and independent-sample t-tests to compare the incidence and intensity of postoperative pain of two groups were carried out. A statistically significant difference was found between the two techniques. When comparing patients who developed no pain, the TF instrumentation technique showed significantly better results (chi-square = 4.059 P = 0.039). When evaluating patients experiencing severe pain the incidence of symptoms was significantly higher with the Reciproc technique (chi-square = 7.246 P = 0.023). Since the incidence of preoperative pain, the type of tooth and the pulp and periodontal pathology were quite similar between the two tested groups, and all the other variables (operator, irrigation, and obturation) were identical, the difference in postoperative p

The aim of the present study is to evaluate the peri-implant soft tissues and the amount of inflammatory cells around two different implant-abutment connections (self-locking conical connection with platform switching and screwed connection with standard abutment and internal anti-rotational system). Histological analysis was made of 14 implants, 7 with self-locking Morse tapered connection (experimental group A) and 7 with screw-retained anti-rotational connection (control group B). Sixty days after non-functional immediate loading, peri-implant tissue biopsies were performed. In the samples taken from the experimental group the peri-implant connective tissue consisted of a greater density of collagen and fibroblasts compared to the connective tissue of the control group. The experimental group specimens showed less inflammatory infiltrate close to the self-locking tapered connection compared to the tissues around the screw-retained connection. The SEM observations showed less microgap in the self-locking conical connection than in the screw connections with standard abutment and internal anti-rotational system. The presence of connective tissue with few inflammatory cells and the absence of inflammatory infiltrate, in self-locking conical connection implants is due to the minimal size of the implant-abutment microgap that does not allow the passage of fluids and bacteria from the oral cavity to the implant thus preventing tissue inflammation. Copyright © by BIOLIFE, s.a.s.