Oral-Gut-Estrobolome Axis May Exert a Selective Impact on Oral Cancer

A subset of bacterial species that holds genes encoding for β-glucuronidase and β-galactosidase, enzymes involved in the metabolism of conjugated estrogens, is called the "estrobolome." There is an emerging interest embracing this concept, as it may exert a selective impact on a number of pathologies, including oral cancer. Although the estrobolome bacteria are typically part of the gut microbiota, recent experimental pieces of evidence have suggested a crosstalk among oral and gut microbiota. In fact, several oral bacterial species are well represented also in the gut microbiota, and these microbes can effectively induce the estrobolome activation. The main pathways used for activating the estrobolome are based on the induction of the expression patterns for 2 bacterial enzymes: β-glucuronidase and aromatase, both involved in the increase of estrogen released in the bloodstream and consequently in the salivary compartment. Mechanistically, high estrogen availability in saliva is responsible for an increase in oral cancer risk for different reasons: briefly, 1) estrogens directly exert biological and metabolic effects on oral mucosa cells; 2) they can modulate the pathological profile of some bacteria, somewhere associated with neoplastic processes (i.e., Fusobacterium spp., Parvimonas ssp.); and 3) some oral bacteria are able to convert estrogens into carcinogenic metabolites, such as 4-hydroxyestrone and 16α-hydroxyestrone (16α-OHE), and can also promote local and systemic inflammation. Nowadays, only a small number of scientific studies have taken into consideration the potential correlations among oral dysbiosis, alterations of the gut estrobolome, and some hormone-dependent cancers: this lack of attention on such a promising topic could be a bias affecting the full understanding of the pathogenesis of several estrogen-related oral pathologies. In our article, we have speculated on the activity of an oral-gut-estrobolome axis, capable of synergizing these 2 important microbiotas, shedding light on a pilot hypothesis requiring further research.

Promoting post-traumatic growth in cancer patients: a randomized controlled trial of guided written disclosure

Background

Cancer is a life-threatening disease that triggers not only vulnerability to distressing symptoms but also a meaning-making process that may lead to post-traumatic growth. As people often struggle to integrate cancer illness into their meaning system to reach an adaptive meaning, psychological interventions focused on a reappraisal of the illness experience can facilitate this process. This multicenter randomized controlled trial (RCT) was primarily aimed at assessing the efficacy of a writing intervention known as a guided disclosure protocol (GDP), compared to a generic writing intervention, in promoting post-traumatic growth in stage I-III breast and colon cancer patients at the end of their adjuvant chemotherapy.

Methods

Between January 2016 and August 2020 recruitment of eligible subjects took place during follow-up clinical consultations. Assessment occurred at baseline (T0), after the intervention (T1, 3 months from baseline), and at 6 months from baseline (T2). Both interventions consisted of three 20-min writing sessions to be performed once every two weeks. Change in post-traumatic growth was assessed using the Posttraumatic Growth Inventory, meaning with the Constructed Meaning Scale, and psychological distress with the Impact of Event Scale and the Hospital Anxiety and Depression Scale.

Results

In the five participating centers, 102 eligible patients were randomized and 72 participants completed follow-up evaluation. Most patients were women (79.4%), had breast cancer (68.6%), and stage I (27.5%), or stage II (44.1%) disease. Mean differences did not reach statistical significance for any of the dependent variables. However, an effect of the GDP, although not statistically relevant, was observed after the intervention in terms of enhanced post-traumatic growth and increased distress measured with the Impact of Event Scale.

Conclusion

This is the first RCT investigating the efficacy of a GDP in cancer patients having post-traumatic growth as the primary aim. Though GDP is a promising intervention in promoting post-traumatic growth, the lack of statistical significance of our findings may be due to the study being underpowered, hence this trial should be replicated with an adequate sample size, paying attention to supporting recruitment.

Clinical trial registration: ClinicalTrials.gov, identifier: 2015/0024360.

Use of fractal analysis in dental images for osteoporosis detection: a systematic review and meta-analysis

Fractal dimension (FD) calculated on oral radiographs has been proposed as a useful tool to screen for osteoporosis. This systematic review and meta-analysis firstly aimed at assessing the reliability of FD measures in distinguishing osteoporotic patients (OP) from healthy controls (HC), and secondly, to identify a standardized procedure of FD calculation in dental radiographs for the possible use as a surrogate measure of osteoporosis. A comprehensive search was conducted up to September 2020 using PubMed, Web of Science, and SCOPUS databases. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Meta-analysis was performed on FD values calculated for HC and OP. Overall, 293 articles were identified. After a three steps screening, 19 studies were included in the qualitative appraisal and 12 were considered for meta-analysis. The methodological quality of the retrieved studies was generally low. Most of the studies included used White and Rudolph and box counting to process the images and to calculate FD, respectively. Overall, 51% of the studies found a meaningful difference between HC and OP groups. Meta-analyses showed that to date, FD measures on dental radiographs are not able to distinguish the OP from HC group significantly. From the current evidence, the use of FD for the identification of OP is not reliable, and no clear conclusion can be drawn due to the heterogeneity of studies. The present review revealed the need for further studies and provided the fundamentals to design them in order to find a standardized procedure for FD calculation (regions for FD assessment; images processing technique; methods for FD measurement). More effort should be made to identify osteoporosis using dental images which are cheap and routinely taken during periodic dental examinations.

COVID-19 pandemic distress among a sample of Italian psycho-oncologists: risk of isolation and loneliness

Purpose:

To measure the prevalence and characteristics of distress and hope for the future among psycho-oncologists, who faced the coronavirus disease 2019 (COVID-19) emergency along with other healthcare workers.

Methods:

A web-based study was conducted among members of the Italian Society of Psycho-Oncology between May 29 and June 5, 2020.

Results:

A total of 237 members, aged 28–72 years, completed the COVID-19 Peritraumatic Distress Index (CPDI), Impact of Event Scale–Revised (IES-R), and HOPE questionnaires; 86.92% were female, 58.65% worked in hospitals, 21.10% were exposed to COVID-19, 11.39% experienced peritraumatic distress, and 3.38% had posttraumatic stress disorder symptoms. Peritraumatic distress was associated with living alone (adjusted odds ratio [AOR] 3.05; 95% confidence interval [CI] 1.41–8.13), using sleep remedies (AOR 3.79; 95% CI 1.41–10.21), and the perception of being avoided by family or friends because of work (AOR 2.69; 95% CI 1.02–7.11); high HOPE-Agency scores were associated with the absence of peritraumatic stress (AOR 0.40; 95% CI 0.16–0.96) after adjustment for age and sex.

Conclusions:

Psycho-oncologists showed greater resilience than other healthcare workers as they are trained to help others, but also to review their own values and behavior in light of stressful events. Of interest is the association between peritraumatic distress and social isolation, real or perceived. Healthcare institutions should pay attention to the mental well-being of their employees by promoting distress screening using simple tools such as the CPDI and implementing support interventions. Psycho-oncology associations should introduce policies aimed at developing a sense of social connectedness by providing an interactive system of orientation and scientific reference.

Effects of a novel gel containing 5-aminolevulinic acid and red LED against bacteria involved in peri-implantitis and other oral infections

Antibiotic resistance is a major public health problem worldwide and the finding of alternative methods for eliminating bacteria is one of the prerogatives of medical research. The indiscriminate use of antibiotics in dentistry, especially for the treatment of peri-implantitis, could lead to superinfections. Alternative methods, like photodynamic therapy mediated by the use of aminolevulinic acid and a red light has been largely described, especially in dentistry, but results were encouraging against Gram-positive bacteria, but limited against Gram-negative. The effectiveness of photodynamic therapy mediated by a novel product containing aminolevulinic acid, Aladent (ALAD) has been tested in this in vitro study, against different types of bacteria particularly involved in the infections of the oral cavity and peri-implantitis. The novelty of ALAD is the marked hydrophilicity that should increase the passage of the molecule through the membrane pores of Gram-negative bacteria. Considering the novelty of the product a preliminary experiment permitted to test the effectiveness against Enterococcus faecalis after 1 h of ALAD incubation at different concentrations, with or without different timings of LED irradiation. The count of CFUs and the live/dead observation with fluorescent microscopy showed a significant reduction and killing of bacterium. Then, in the second stage, that could meet the necessity of effectiveness and the clinician's requests to reduce the timing of treatment, ALAD, with and without irradiation, was tested on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Veillonella parvula and Porphyromonas gingivalis. In particular, the efficiency of different concentrations of the product after a 25 min incubation was tested with and without the adjunctive LED irradiation for 5 min. A slight ALAD bactericidal effect was reported for all bacteria, also without LED irradiation, however, the most effective treatment was 25 min of 50% ALAD incubation followed by 5 min of a red LED. The in vitro tests demonstrated that ALAD gel with LED irradiation exerts a potent antibacterial activity on different bacteria, both Gram-positive and Gram-negative.

Implant insertion torque value in immediate loading: A retrospective study

BACKGROUND

The aim of this study is to verify if the Insertion Torque Value (ITV) of 32 Ncm for immediate loading protocol (ILP), as indicated by literature, is still, with the advance in implant research, a real significant cut-off for long-term implant survival.

MATERIAL AND METHODS

In this retrospective study, data from 224 patients that during three years of clinical practice, were submitted to the insertion of 322 implants with immediate loading protocol, have been recorded, pooled and analyzed. Data were organized based on Insertion Torque Value (ITV): > 32 Ncm (CG) and < 32 Ncm (LTG) and two different groups of equal sample size, 161 implants each, were distinguished. Crestal bone reabsorption, and the implant failure rate were evaluated after 2-years of follow-up.

RESULTS

The bone reabsorption in LTG (0.49 ± 0.11 mm ) was significantly greater than CG (0.22 ± 0.04 mm), p<0.001. However, the survival rate after 2-years of follow-up was quite high and similar for both groups: 96.89% for LTG and 97.52% for CG and no statistically significant differences have been found among the two groups for the implant failure rate (p=0.455).The Odds Ratio (OR) of implant failure was of 1.258 (95% CI 0.332, 4.772), but results were not statistical significant, p=0.740.

CONCLUSIONS

The present study showed that although implants with ITV> 32 Ncm are still characterized by a lower crestal bone resorption, there are no statistically significant differences among the two groups for what concerning the failure rate during the 2 years of follow-up and OR. These results permit us to suppose that the cut-off of ITV >32 Ncm for immediate loading implants, could be reduced to inferior values. However further studies are necessary to indicate precise clinical guidelines.

WITHDROWN: Effect of smoking habit on crestal bone height in maxillary sinus augmentation with bone grafts

In relation to the article with reference “Carreño-Carreño J, Gómez-Moreno G, Aguilar-Salvatierra A, Menéndez-López-Mateos C, Piattelli A, Menéndez-Núñez M. Effect of smoking habit on crestal bone height in maxillary sinus augmentation with bone grafts. Med Oral Patol Oral Cir Bucal. (2018), doi:10.4317/medoral.22439”, published in Oral Medicine Oral Pathology and Oral Surgery in the modality "AHEAD OF PRINT - article in press", the authors mention that "The study was conducted according to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) Statement". However, and based on the opinion of several expert reviewers who have re-evaluated the article, it is considered that although "there has not been plagiarism", these STROBE criteria are not adequately met. In addition, the mentioned article is very similar to two articles that have already been published by the same authors in Clinical Oral Implants Research. The sample is the same; many data are repeated; and the only difference is the inclusion of a variable (smoking), which does not exert a significant effect. This outcome therefore would not justify publication of the paper in the journal. Retraction of the article is therefore decided.

Response of periodontium to mineral trioxide aggregate and Biodentine: a pilot histological study on humans

BACKGROUND

The aim of this study was to investigate for the first time the histological response of human periodontium to mineral trioxide aggregate (MTA) and Biodentine.

METHODS

Six patients scheduled for implant full-arch rehabilitation were randomly assigned to one of the two test groups: MTA or Biodentine treatment. For each patient, two teeth scheduled for strategic extraction were randomly assigned either to the test or to the control treatment. A lateral perforation was drilled on the root and either repaired with MTA/Biodentine or filled with gutta-percha(control). Three months later, the teeth were extracted along with the coronal third of the alveolar bone and a portion of gingival tissue, while performing implant placement, and processed for histological analysis.

RESULTS

Biodentine resulted in less extrusion into the periodontal environment. All the materials showed good biocompatibility. A new mineralized cementum-like tissue incorporating periodontal fibres was visible in all cases treated with MTA. A small amount of new mineralized tissue was found in two Biodentine cases but not in control cases. Biodentine resulted in less damage to the periodontal ligament.

CONCLUSIONS

Bioactivity and biocompatibility of MTA were confirmed in human models. Biodentine proved to be biocompatible, but it seems not to induce cementum regeneration.

Removal Torque Values of Titanium Implants Inserted into Bone Defects Filled with Hydroxyapatite: A Histologic and Histomorphometric Analysis in Rabbit

The successful clinical use of implants with microrough titanium surfaces has paved the way for the further development of surface topographies to promote enhanced peri-implant bone apposition during the early stages of bone regeneration. The aim of this study is to determine the torque resistance of the implant-bone interface of plasma sprayed titanium endosseous implants placed in the rabbit tibia in three different situations. Hydroxyapatite (HA) particles with a size ranging from 250 to 450 microm were used in the present study to fill out 6 mm bony defects created in rabbit tibia. Fourteen mature New Zealand white male rabbits, weighing about 2.5 Kg., were used in this study. The test sites were filled with HA and the non-grafted sites were used as control. A total of 28 bone defects (14 without HA and 14 with HA.) were created. Implants with plasma-spray surface were subsequently inserted. Six additional rabbits were used; in these animals no bone defects were created. The implant sites were divided into three groups: 1) implants inserted in the tibia without bone defects; 2) implants inserted in the tibia with bone defects not filled with HA; 3) implants inserted in the tibia with bone defects filled with HA particles. The purpose of this study is to measure reverse-torque in three different situations of clinically similar implant geometry in the articulation of rabbits. The null hypothesis stated that there is a difference in reversal torque between the bone regeneration with HA, native bone and bone defect without bone regeneration. Additionally, comparison between these 6-month data and the 3-month data from a previous study led to the following conclusions: a significant difference exists in the removed torque for the TPS implants in the bone regenerated by HA and native bone; increase in removal torque values was seen for the implant inserted in bone regenerated by HA compared to the implant nated in bone without biomaterials. In conclusion, bone regenerated with biomaterials possesses different mechanical characteristics to native bone.

Correlation between Implant Stability Quotient (ISQ) with Clinical and Histological Aspects of Dental Implants Removed for Mobility

Dental implants are a successful treatment modality for missing teeth; however, failures do occur. These failures can occur early in the healing process after primary stability has been achieved at the time of implant placement, or after initial bone remodeling and new bone growth have taken place. The ability to detect implants that are failing or will fail is still not possible. The aim of the present study is to see if correlations exist between RFA values and histologic and histochemical evaluation of the human retrieved implants for failure. In a 5 year period, 37 root form implants were retrieved because of mobility and underwent histological examination. Thin ground sections were obtained from each implant. All the implants had been removed with a 5 mm trephine. In all cases a peri-implant radiolucency was present. Before implant retrieval, the implant stability was evaluated with Osstell (Integration Diagnostics AB, Gothenburg, Sweden). All the implants were not osseointegrated clinically and mobility was present. Radiographically, bone loss was observed around the implants and the mean ISQ values was 37 (+/- 2.7). A scarce inflammatory cell infiltrate was present in the connective tissue of some specimens. In about 10 percent of specimens, the epithelium tended to surround the total perimeter of the implant. These data suggest that implants with an ISQ<40 are irretrievably lost and there is no possibility to save them. A statistically significant correlation was found between an ISQ<36 and irretrievably failed implants.

Sem and Fractography Analysis of Screw Thread Loosening in Dental Implants

Biological and technical failures of implants have already been reported. Mechanical factors are certainly of importance in implant failures, even if their exact nature has not yet been established. The abutment screw fracture or loosening represents a rare, but quite unpleasant failure. The aim of the present research is an analysis and structural examination of screw thread or abutment loosening compared with screw threads or abutment without loosening. The loosening of screw threads was compared to screw thread without loosening of three different implant systems; Branemark (Nobel Biocare, Gothenburg, Sweden), T.B.R. implant systems (Benax, Ancona, Italy) and Restore (Lifecore Biomedical, Chaska, Minnesota, USA). In this study broken screws were excluded. A total of 16 screw thread loosenings were observed (Group I) (4 Branemark, 4 T.B.R and 5 Restore), 10 screw threads without loosening were removed (Group II), and 6 screw threads as received by the manufacturer (unused) (Group III) were used as control (2 Branemark, 2 T.B.R and 2 Restore). The loosened abutment screws were retrieved and analyzed under SEM. Many alterations and deformations were present in concavities and convexities of screw threads in group I. No macroscopic alterations or deformations were observed in groups II and III. A statistical difference of the presence of microcracks were observed between screw threads with an abutment loosening and screw threads without an abutment loosening.

Human periodontal ligament stem cells cultured onto cortico-cancellous scaffold drive bone regenerative process

The purpose of this work was to test, in vitro and in vivo, a new tissue-engineered construct constituted by porcine cortico-cancellous scaffold (Osteobiol Dual Block) (DB) and xeno-free ex vivo culture of human Periodontal Ligament Stem Cells (hPDLSCs). hPDLSCs cultured in xeno-free media formulation preserved the stem cells' morphological features, the expression of stemness and pluripotency markers, and their ability to differentiate into mesenchymal lineage. Transmission electron microscopy analysis suggested that after one week of culture, both noninduced and osteogenic differentiation induced cells joined and grew on DB secreting extracellular matrix (ECM) that in osteogenic induced samples was hierarchically assembled in fibrils. Quantitative RT-PCR (qRT-PCR) showed the upregulation of key genes involved in the bone differentiation pathway in both differentiated and undifferentiated hPDLSCs cultured with DB (hPDLSCs/DB). Functional studies revealed a significant increased response of calcium transients in the presence of DB, both in undifferentiated and differentiated cells stimulated with calcitonin and parathormone, suggesting that the biomaterial could drive the osteogenic differentiation process of hPDLSCs. These data were confirmed by the increase of gene expression of L-type voltage-dependent Ca2+ (VDCCL), subunits α1C and α2D1 in undifferentiated cells in the presence of DB. In vivo implantation of the hPDLSCs/DB living construct in the mouse calvaria evidenced a precocious osteointegration and vascularisation process. Our results suggest consideration of DB as a biocompatible, osteoinductive and osteoconductive biomaterial, making it a promising tool to regulate cell activities in biological environments and for a potential use in the development of new custom-made tissue engineering.

Factors Associated with Apoptosis in Symptomatic and Asymptomatic Carotid Atherosclerotic Plaques

The aim of this study was to investigate the differences that are present between apoptosis in symptomatic (with symptoms of cerebral ischemic attack) and asymptomatic carotid atherosclerotic plaques. The apoptotic process in macrophages and smooth muscle cells was evaluated. Cellular markers and products of immune cells in symptomatic and asymptomatic atherosclerotic plaque and endoarterectomy specimen were analyzed by immunohistochemistry. No statistically significant differences were present regarding the mean SMC actin-positive area. Using double staining of α-smooth muscle actin and TUNEL techniques, the number of smooth muscle cells in apoptosis was statistically higher in symptomatic plaque as compared with asymptomatic plaque. Statistically significant differences (p=0.009) were also found in the CD45-positive cells in the inflammatory infiltrate. The CD68-positive macrophages showed statistically significant differences (p=0.0001). Similarly, the double staining with CD68 and TUNEL revealed that apoptotic macrophages were mainly present in asymptomatic plaques rather than symptomatic plaques. Statistically significant differences (p<0.001) were found in the Bcl-2 expression, with higher values in asymptomatic plaques. Our data showed that the increase of the inflammatory cells contributes to plaque instability and that death due to apoptosis of smooth muscle cells in symptomatic plaques could contribute to their destabilization and explains their tendency to fracture.

Potential Markers of Tongue Tumor Progression Selected by cDNA Micro Array

Squamous cell carcinoma (SCC), the most frequent malignant tumor of the oral cavity, generally exhibits a poor prognosis and metastases are the main cause of death. This tumor often arises from pre-malignant lesions. To date, it is difficult to predict if and which pre-malignant lesions may progress into oral SCC using traditional methods. For these reasons, several studies are trying to identify markers useful in the progression of pre-malignant lesions and tumors. To define the genetic expression profile of tongue tumor progression we compared 9 dysplasias (DS), 8 tumors without metastasis (TWM), 11 metastasizing SCCs (MT) of the tongue, and a baseline of 11 normal tissues by using cDNA microarray containing 19.2 K clones. We initially applied hierarchical agglomerative clustering based on information from all 6026 clones. Results were obtained by performing a two steps analysis: a Significance Analysis of Microarray (SAM) and a Gene Ontology search. One hundred and five clones have statistically significant different expression levels (FDR <0.01) between DS and TWM, whereas 570 genes have statistically significant difference expression levels between TWM and MT (FDR <0.01) as detected by SAM. By filtering with FatiGo only 33 genes were differentially expressed in TWN, respect to DS, whereas 155 genes were differentially expressed in MT respect to TWM. We detected some genes which encode for oncogenes, transcription factors and cell cycle regulators as potential markers of DS progression. Examples are BAG4, PAX3 and CCNI, respectively. Among potential markers of metastases are some genes related to cell mobility (TSPAN-2 and SNTA1), intercellular adhesion (integrin alpha 7) or extracellular matrix components (ADAMTS2 and cathepsin O). Additionally, under-expressed genes encoded apoptosis-related proteins (PDCD4 and CASP4). In conclusion, we identified several genes differentially expressed in tumor progression which can potentially help in better classifying premalignant lesions and tongue SCCs.

Vascular Endothelial Growth Factor Expression (VEGF) in Salivary Glands of Young and Old Hyperoxic Rats

The aim of this study is to evaluate whether hyperoxia and age can influence the expression of vascular endothelial growth factor (VEGF) in the salivary glands of rats. Our study was carried out on four groups of male Wistar rats (total 24 rats). One group was composed of 6 young rats (3 months old); another group by 6 old rats (24 months old). The rats belonging to the first two groups were exposed to hyperoxia (98–100% O2) for a period of 60–65 hours in a large Plexiglas chamber; the other two groups were control groups. The rats were then anaesthetized with Nembutal (30 mg/kg) intraperitoneally and then killed. The submandibular glands were removed and processed for immunohistochemical analysis of VEGF. The exposure to hyperoxia decreased salivary gland VEGF expression in rats. The tissues analyzed (nervous tissue, vascular endothelium, myoepithelial cells, ductal endothelium, mucinous glands) always expressed VEGF, thus demonstrating that not only vascular endothelial cells, but also the other elements evaluated, have a role in the neoangiogenesis. Only in the serous glands, in both normoxic and hyperoxic young and old rats, was the VEGF expression constantly negative and it did not influence the neoangiogenesis. The vascular growth is a fundamental part of normal salivary gland development, so we speculated that strategies aimed at preservation or promotion of salivary gland VEGF expression may mitigate or attenuate hyperoxia-induced gland microvascular injury. Further studies specifically aimed at investigating these prospects are warranted.

Osteogenic potential of dualblocks cultured with human periodontal ligament stem cells: in vitro and synchrotron microtomography study

BACKGROUND AND OBJECTIVE

In the present study, the early stages of in vitro bone formation in collagenated porcine scaffolds cultured with human periodontal ligament cells were investigated. The comparison between the osteogenic potential of this structure in basal and differentiating culture media was explored to predict the mechanism of its biological behavior as graft in human defect. Results were validated by synchrotron radiation X-Ray phase contrast computed microtomography (micro-CT). As the periodontal disease plays a key role in systemic and oral diseases, it is crucial to find advanced therapeutic clinical interventions to repair periodontal defects. This has been recently explored using cells and tissues developed in vitro that should ideally be immunologically, functionally, structurally and mechanically identical to the native tissue.

MATERIAL AND METHODS

In vitro cultures of human periodontal ligament cells, easily obtained by scraping of alveolar crestal and horizontal fibers of the periodontal ligament, were seeded on to collagenated porcine blocks constituted by natural cancellous and cortical bone. 3D images were obtained by synchrotron radiation micro-CT and processed with a phase-retrieval algorithm based on the transport of intensity equation.

RESULTS

Starting from the second week of culture, newly formed mineralized bone was detected in all the scaffolds, both in basal and differentiating media. Bone mineralization was proved to occur preferentially in the trabecular portion and in differentiating media.

CONCLUSION

The chosen method, supported by phase contrast micro-CT analysis, successfully and quantitatively monitored the early stages of bone formation and the rate of the bioscaffold resorption in basal and differentiating culture media.

Micro-topography and reactivity of implant surfaces: an in vitro study in simulated body fluid (SBF)

The creation of micro-textured dental implant surfaces possessing a stimulating activity represents a challenge in implant dentistry; particularly, the formation of a thin, biologically active, calcium-phosphate layer on their surface could help to strengthen the bond to the surrounding bone. The aim of the present study was to characterize in terms of macrostructure, micro-topography and reactivity in simulated body fluid (SBF), the surface of titanium (Ti) implants blasted with TiO2 particles, acid etched with hydrofluoric acid, and activated with Ca and Mg-containing nanoparticles. Sandblasted and acid-etched implants were analyzed by ESEM-EDX (environmental scanning electron microscope with energy dispersive X-ray system) to study the micromorphology of the surface and to perform elemental X-ray microanalysis (microchemical analyses) and element mapping. ESEM-EDX analyses were performed at time 0 and after a 28-day soaking period in SBF Hank's balanced salt solution (HBSS) following ISO 23317 (implants for surgery—in vitro evaluation for apatite-forming ability of implant materials). Microchemical analyses (weight % and atomic %) and element mapping were carried out to evaluate the relative element content, element distribution, and calcium/phosphorus (Ca/P) atomic ratio. Raman spectroscopy was used to assess the possible presence of impurities due to manufacturing and to investigate the phases formed upon HBSS soaking. Micro-morphological analyses showed a micro-textured, highly rough surface with microgrooves. Microchemical analyses showed compositional differences among the apical, middle, and distal thirds. The micro-Raman analyses of the as-received implant showed the presence of amorphous Ti oxide and traces of anatase, calcite, and a carbonaceous material derived from the decomposition of an organic component of lipidic nature (presumably used as lubricant). A uniform layer of Ca-poor calcium phosphates (CaPs) (Ca/P ratio <1.47) was observed after soaking in HBSS; the detection of the 961 cm⁻¹ Raman band confirms this finding. These implants showed a micro-textured surface supporting the formation of CaPs when immersed in SBF. These properties may likely favor bone anchorage and healing by stimulation of mineralizing cells.

Spontaneous bone formation on the maxillary sinus floor in association with surgery to remove a migrated dental implant: a case report

AIM

A variety of surgical techniques have been developed to reconstruct the posterior maxilla when bone volume is insufficient. For some decades, sinus augmentation, using various bone substitutes, has been used to reconstruct the posterior maxilla for dental implant placement. Even if new bone formation is achieved in the sinus after bone grafting, the possibility of new bone formation with only a membrane elevation in the maxillary sinus has been reported in human and animal studies. The aim of this case report was to document an unexpected healing pattern after the removal of a dental implant migrated in the maxillary sinus.

METHODS

In October 2009 a 49-year-old man with a partially edentulous maxilla underwent implant placement. Specifically, a total of 5 implants were inserted, 2 in the left and 3 in the right posterior maxilla. Four months later, at the time of abutment connection, the implant at the site of the maxillary left first molar was accidentally pushed in the sinus. A surgical removal of the implant from the maxillary sinus was proposed and the patient consented to the surgical intervention. Computed axial tomography (CAT) scan images revealed opacification of the left maxillary sinus with mucosal thickening, and the dental implant displaced within the sinus. The planned treatment sequence was: 1) removal of the implant; 2) sinus augmentation procedure after 5 months; 3) implant insertion 5 months after the bone graft. The implant was removed. Five months later, the patient was admitted for the bone-grafting augmentation procedure. A new CAT scan image revealed normal mucosal thickness and no opacification of the left maxillary sinus; bone formation was evident. The surgery was undertaken with local anesthesia and conscious sedation.

RESULTS

At reentry, the sinus wall was found to be totally healed. Newly formed bone (21.2%) with wide osteocyte lacunae and large marrow spaces (73.8%) were present with newly formed vessels and no inflammatory cell infiltrate.

CONCLUSION

The surgical trauma and the creation of a secluded space between the bone surfaces and the healed sinus mucosa resulted in a spontaneous bone formation in the maxillary sinus. The surgical approach described may be used to achieve bone formation to enable placement of dental implants without the addition of any grafting material.

Evaluation of scientific production in oral surgery in Italy from 1998 to 2012

AIM

Dental research, especially in the field of oral surgery, showed a strong and significant increase during the last years. This was probably determined by the introduction among the clinicians of different therapeutic protocols through biomaterials engineering, and by the large broadcasting of scientific knowledge due to new media such as the internet. The aim of this work was to analyze the scientific production of a sample of Italian Oral Surgeons from 1998 to 2012.

METHODS

The scientific production of 252 Active Members belonging to three Italian associations of Oral Surgery (SIdCO, SIO, SICOI) was examined. The number of authors, the number of publications and the number of citation were quantified for three periods of 5 years each from the first year considered along 15 years. The overall sample was then divided into two groups, academics and not academics, in order to differently assess the scientific production conducted inside or outside the University.

RESULTS

Over the years, scientific production increased considerably, with a progression not strictly proportional if compared to the number of authors, especially in the last 5 years. By spearately considering the academics and the not academics authors, the biggest contribution to the scientific production increasingly came from the last 5 years, both in terms of authors' and published papers number.

CONCLUSION

The results reported in this bibliometric analysis show how scientific research increasingly pursued by clinicians in oral surgery in the last 15 years.

Pro-inflammatory cytokine release and cell growth inhibition in primary human oral cells after exposure to endodontic sealer

AIM

To assay the toxicity of the single-methacrylate-based sealer urethane dimethacrylate (UDMA) (EndoRez) in terms of cell growth and pro-inflammatory cytokines release, in expanded ex vivo human dental pulp stem cells (hDPSCs), human periodontal ligament stem cells (hPDLSCs), human gingival fibroblasts (hGFs) and human osteoblasts (hOSTs).

METHODOLOGY

Dental pulp and periodontal ligament stem cells, osteoblasts and fibroblasts were derived from five young donors. After in vitro isolation, hDPSCs, hPDLSCs, hGFs and hOSTs were seeded to resin-based sealers for 24, 48, 72 h up to 1 week. The morphological features and the cell growth and the release of pro-inflammatory interleukin (IL)6, IL8, IL12 and tumour necrosis factor (TNF) α were analysed. Differences in cell growth and in interleukin secretion were analysed for statistical significance with two-way anova tests for multiple comparisons.

RESULTS

Exposure to endodontic sealer based on UDMA resulted in a 50% decrease in survival oral cells at 24 h of incubation. No evident morphological changes were present in cell cultures examined. After 48 h, 72 h and 1-week culture time, a progressive cell growth was evident. A significant up-regulation of IL6, IL8, IL12 and TNFα cytokines in cells in contact with the dental sealer compared to the control was observed.

CONCLUSION

In vitro, EndoRez interacted with primary human hDPSCs, hPDLSCs, hGFs and hOSTs causing damage to biological system evidenced through cell growth inhibition and up-regulation of IL6, IL8, IL12 and TNFα proinflammatory mediators.

Patients attitudes towards sleep disturbances during chemotherapy

Sleep disturbances are among the most distressing symptoms in cancer: they often co-occur with fatigue, pain and psychological distress. Despite the negative impact on quality of life, patients rarely seek help for managing their sleep disturbances. This paper presents the results of a multicentre observational study on patients' attitudes towards their sleep problems. The study also investigates symptom correlates. Patients responded to a semi-structured interview and completed the following questionnaires: Pittsburgh Sleep Quality Index; Brief Fatigue Inventory; Hospital Anxiety and Depression Scale; and European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life QLQ-C30 Questionnaire (QLQ-C30). Four hundred and three cancer patients were enrolled in the study. Bad sleepers constituted 66% of the sample. Thirty-eight per cent of them had not turned to any professional to solve their sleep disturbances because they had various beliefs about the importance of the problem and the possibility to be treated. The main correlates of sleep disturbances were psychological distress, reduced physical functioning and reduced overall quality of life. In conclusion, there is a need to sensitise patients to actively search for a solution to their sleep disturbances so they can be solved along with other co-occurring symptoms. Doctors could also be encouraged to dedicate more attention to routinely asking cancer patients about eventual sleep disturbances.

Maxillary sinus augmentation procedures through equine-derived biomaterial or calvaria autologous bone: immunohistochemical evaluation of OPG/RANKL in humans

Autologous bone is considered the gold standard for bone regeneration, even if different heterologous bone substitutes have been proposed to overcome the limits related to its use. The aim of this study was to analyze and to compare the molecular events switched on by autologous or heterologous bone graft insertion, focusing on TGFβ1 expression and OPG/RANKL ratio, to analyze resorption process, and estimating graft vascularization, new bone tissue deposition and its mineralization, through VEGF, BSP and SPARC expression evaluation, respectively. Patients needing pre-prosthetic rehabilitation of the posterior maxilla were treated using an equine-derived biomaterial (Group 1) or calvaria autologous bone (Group 2), according to the morphology of the bone defect. Bone graft integration was evaluated on bone samples obtained from the treated areas at the moment of dental implant insertion, by morphological and immunohistochemical analyses for TGFβ1, OPG, RANKL, VEGF, BSP, and SPARC expression. Morpho - logical analysis shows the presence of biomaterial residual granules in Group 1, in parallel to a good integration between graft and host tissue. Moderate TGFβ1 expression is seen in both Group 1 and Group 2. OPG/RANKL ratio appears higher in Group 1; VEGF expression appears very strong in Group 1 and strong in Group 2, while BSP and SPARC expression results weak in Group 1 and moderate in Group 2. Our results reveal the good integration between both types of graft and the host tissue, even though autologous graft seems to produce a faster regenerative process, as evidenced by the different expression of the investigated molecules. According to these observations, the clinical use of heterologous particulate equine-derived biomaterial may ensure long-term predictability of implantprosthetic rehabilitation, comparable to that obtained with autologous bone graft.

Bucco-Lingual Crestal Bone Changes Around Implants Immediately Placed in Fresh Extraction Sockets in Association or not With Porcine Bone: A Non-Blinded Randomized Controlled Trial in Humans

Background: The aim of the present randomized controlled clinical trial was to assess the bucco-lingual bone changes of implants immediately placed in fresh extraction sockets in association or not with porcine bone. Methods: Forty patients were included in the present study, and were randomly assigned to the control (n = 20) and test (n = 20) groups. Each patient received a single implant placed into an immediate extraction site of a molar or a first upper premolar with a flapless approach. In the control sites no grafting material was placed, while in the tests a deantigenated collagenated bone substitute of porcine origin was used to fill the gaps between the implant and the extraction socket. The bucco-lingual bone width was measured at different time points: at the time of surgery (T0), at 90 days (T1), at 110 days (T2) and after 6 months of masticatory function (T3). The values were statistically analyzed between and within the treatment groups (p>0.05). Results: All the implants were osseointegrated. Four control implants were excluded from the analysis due to the exposure of the coronal portion of the fixture. At T1, T2 and T3, statistically significant differences were found by comparing the mean width of the bucco-lingual bone between control and test groups. The mean values decreased during the observation period in both groups; statistically significant differences within controls were detected at T1, T2 and T3, and at T2 and T3 within tests. Conclusions: The outcomes of present study suggested that porcine bone enabled to avoid bucco-lingual crestal bone changes in implants immediately placed in fresh extraction sockets.

Management of compound odontoma in a 10-year-old girl preserving the associated impacted permanent tooth

AIM

Compound odontoma has been reported to be the most common of all odontogenic neoplasms and tumor- like lesions. Only rarely the treatment of this lesion in association with an impacted tooth has been reported.

CASE REPORT

A compound odontoma in a 10-year-old girl, associated with an impacted permanent incisor is described, focusing on the diagnosis and the importance of early treatment of this lesion. The patient underwent surgical excision of the lesion and it was decided to wait for the spontaneous eruption of the impacted tooth. After 6 months no eruption was observed and thus the orthodontic treatment was deemed necessary. At the one-year follow-up, the tooth was brought into the maxillary arch.

First report of an acute purulent maxillary sinusitis caused by Pseudomonas aeruginosa secondary to dental implant placement in an immunocompetent patient

STUDY DESIGN

In this case report, we present maxillary Pseudomonas aeruginosa sinusitis in an immunocompetent patient who underwent an autologous bone transplant for the insertion of dental implants.

RESULTS

The infection was eradicated after removal of the dental implants and long-term antibiotic therapy.

CONCLUSION

Despite the infection resolution, severe complications were observed with important legal consequences.

Patients with Peri-Implantitis, unlike Those with a Healthy Peri-Implant Microenvironment, Display Antibodies to More Than One Heat Shock Protein (HSP 27, HSP 65 and HSP 90) Linear Epitope

The success of a dental implant treatment requires hard and soft tissue integration and osseointegration, mechanisms that entail a direct anchorage of the implant in the bone without interposition of soft tissue. Peri-implantitis is defined as an inflammatory reaction of the tissues surrounding a functioning dental implant. During inflammation, a high incidence of autoantibodies has been reported. The hypothesis of the present study is that the occurrence of autoantibodies to self-antigens including extracellular matrix (ECM) molecules and heat shock proteins (HSPs) might affect the dental implant outcome. Therefore, we evaluated the occurrence of antibodies to ECM molecules (Collagen (C) I, III, IV, V, fibronectin, laminin) and HSPs (HSP 27, HSP 65, HSP 90) in subjects with a healthy peri-implant microenvironment (n=29) as compared to patients with peri-implantitis (n=13). We also evaluated the HSP 27 expression in gingival fibroblasts grown in an inflammatory microenvironment. Antibodies to conformational ECM epitopes of CI, CIII and laminin were observed both in subjects with healthy peri-implant conditions and peri-implantitis. Antibodies to more than one HSP linear epitope were found in patients with peri-implantitis but not with healthy peri-implant conditions (p=0.024). Gingival fibroblasts grown in an inflammatory microenvironment showed increased HSP 27 cytoplasmic and plasma membrane expression as compared to fibroblasts grown in normal conditions. Immunity to multiple linear HSPs epitopes in patients with peri-implantitis and not in patients with a healthy peri-implant microenvironment might be relevant for monitoring the implant outcome and help to understand the role of subsets of autoantibodies in implant osseointegration.

Wear of dental sealing materials using the replication technique

AIM

The aim of the present study was an in vivo evaluation of the wear of different sealing materials using the replication technique.

MATERIALS AND METHODS

Four different sealing materials were randomly applied on 2 out of 4 caries-free permanent first molars of each patient. Impressions were taken at T0: before the sealing material was applied; T1: right after the application; T2: 6 months after the application, and T3: 1 year after the application. The impressions were then processed for scanning electron microscopy analysis of the wear of the examined materials. Statistical analysis was used to evaluate differences among and within the 4 groups.

RESULTS

At T2, the average ratio of residual material in all the groups was 62.37% ± 1.21%, while at T3 it was 49.63% ± 1.11%. At both T2 and T3 there were no statistically significant differences among the 4 groups examined (p=0.76 and p=0.50 respectively). Comparison within the same group at T2 and T3 showed that statistically significant differences were only detected in group D (p=0.015).

CONCLUSION

Sealing materials do not undergo a complete loss after 1 year of application, thus indicating that they are suitable for caries prevention.

Assessment of Pain Associated with Insertion Torque of Dental Implants. A Prospective, Randomized-Controlled Study

This study investigated pain experience following dental implant placement in relation to insertion torque using questionnaires. A total 80 implants were placed in 20 patients. Each patient received 4 implants at different times. One implant was inserted and, then, after 40 days was placed the second implant, after 80 days was placed the third implant and after 120 days was placed the fourth implant. At each time the peri-implant bone levels were evaluated on intraoral radiographs taken with the paralleling technique. The implants were placed with a dynamometric key at 35N, 50N, 65N, 85N. Patients were asked to evaluate their pain experience during surgery, 24 hours after surgery, and at 2 days, 4 days, 1, 2, and 4 weeks after surgery on special pain assessment forms. A separate form was used for each time point. Pain was assessed using a descriptive numerical rating scale of 0 to 10, with 0 indicative of no pain and 10 representing the worst pain imaginable. Patients were instructed that a score of 1 to 3 was indicative of mild pain, 4 to 6 was indicative of moderate pain, and 7 to 10 was indicative of severe pain. A significant correlation pain scores and insertion torque was found between group III and group IV vs group II and group I during surgery, at 24 hours, 2 days, 4 days, 1 week, 2 weeks p⩽0.05. No statistical difference was found between group I vs. group II during surgery, at 24 hours, 2 days, 4 days, 1 week, 2 weeks p⩾0.05. In conclusion, elevated insertion torque values produces pain and resoption of the crestal bone around the implants.

Solid variant of keratocystic odontogenic tumour: report of a case

This case report presents a solid variant of keratocystic odontogenic tumour (KCOT), a benign uni- or multicystic intraosseous tumour of odontogenic origin, with a characteristic lining of parakeratinized stratified squamous epithelium and potential inflammatory infiltrate. A 52-year old female patient discovered occasionally, in an orthopantomography done for other reasons, the presence of a radiolucent lesion. A 2-3 cm wide lesion with well-demarcated margins was present in the premolar region of the left hemimandible. Under local anesthesia a biopsy was done and the diagnosis of odontogenic keratocyst was confirmed by histopathological examination. Under general anesthesia, the lesion was easily shelled-out and completely enucleated. The lesion had not recurred after a 6 years follow-up. The occurrence of a solid variant of KCOT could strengthen the hypothesis of a neoplastic rather than cystic nature of this lesion.

Functional assay, expression of growth factors and proteins modulating bone-arrangement in human osteoblasts seeded on an anorganic bovine bone biomaterial

The basic aspects of bone tissue engineering include chemical composition and geometry of the scaffold design, because it is very important to improve not only cell attachment and growth but especially osteodifferentiation, bone tissue formation, and vascularization. Geistlich Bio-Oss (GBO) is a xenograft consisting of deproteinized, sterilized bovine bone, chemically and physically identical to the mineral phase of human bone. In this study, we investigated the growth behaviour and the ability to form focal adhesions on the substrate, using vinculin, a cytoskeletal protein, as a marker. Moreover, the expression of bone specific proteins and growth factors such as type I collagen, osteopontin, bone sialoprotein, bone morphogenetic protein-2 (BMP-2), BMP-7 and de novo synthesis of osteocalcin in normal human osteoblasts (NHOst) seeded on xenogenic GBO were evaluated. Our observations suggest that after four weeks of culture in differentiation medium, the NHOst showed a high affinity for the three dimensional biomaterial; in fact, cellular proliferation, migration and colonization were clearly evident. The osteogenic differentiation process, as demonstrated by morphological, histochemical, energy dispersive X-ray microanalysis and biochemical analysis was mostly obvious in the NHOst grown on three-dimensional inorganic bovine bone biomaterial. Functional studies displayed a clear and significant response to calcitonin when the cells were differentiated. In addition, the presence of the biomaterial improved the response, suggesting that it could drive the differentiation of these cells towards a more differentiated osteogenic phenotype. These results encourage us to consider GBO an adequate biocompatible three-dimensional biomaterial, indicating its potential use for the development of tissue-engineering techniques.

Regenerative potential of human periodontal ligament derived stem cells on three-dimensional biomaterials: a morphological report

Recent studies have shown that mesenchymal stem cells obtained from periodontal ligament (PDL-MSCs) are multipotent cells that have similar features of the bone marrow and dental pulp MSCs and are capable of proliferating and producing different types of tissue such as bone and tooth associated-tissues. Human PDL-MSCs expanded ex vivo were induced to osteogenesis, seeded in three-dimensional biocompatible scaffolds (fibrin sponge, bovine-derived substitutes) and examined using light, scanning and transmission electron microscopy. Morphological observations showed extensive growth of cellular biomass partially covering the scaffolds after 4 weeks of incubation in mineralization medium. These findings indicate that periodontal ligament can be an easily and efficient autologous source of stem cells with a high expansion capacity and ability to differentiate in osteogenic cells that can colonize and grow connected to bio-compatible scaffold. It can be suggested that the use of PDL-MSCs for generating graft biomaterials is advantageous for bone tissue engineering in regenerative dentistry.

VEGF and MVD expression in sinus augmentation with autologous bone and several graft materials

OBJECTIVE

The aim of this study was to assess vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in maxillary sinus augmentation with autogenous bone and different graft materials for evaluating their angiogenic potential.

METHODS

Biopsies were harvested 10 months after sinus augmentation with a combination of autogenous bone and different graft materials: hydroxyapatite (HA, n = 6 patients), demineralized freeze-dried bone allograft (DFDBA, n = 5 patients), calcium phosphate (CP, n = 5 patients), Ricinus communis polymer (n = 5 patients) and control group--autogenous bone only (n = 13 patients).

RESULTS

In all the samples, higher intensities of VEGF expression were prevalent in the newly formed bone, while lower intensities of VEGF expression were predominant in the areas of mature bone. The highest intensity of VEGF expression in the newly formed bone was expressed by HA (P < 0.001) and CP in relation to control (P < 0.01) groups. The lowest intensities of VEGF expression in newly formed bone were shown by DFDBA and polymer groups (P < 0.05). When comparing the different grafting materials, higher MVD were found in the newly formed bone around control, HA and CP (P < 0.001).

CONCLUSION

Various graft materials could be successfully used for sinus floor augmentation; however, the interactions between bone formation and angiogenesis remain to be fully characterized.

Peripheral giant cell granuloma associated with a dental implant. A case report

Peripheral giant cell granuloma (PGCG) is a tumor-like pathologic condition arising on the buccal or lingual attached gingival or alveolar mucosa and the crest of the edentulous alveolar ridge, of uncertain etiology; it is probably a reactive lesion caused by chronic local irritants or trauma rather than a true neoplasm. PGCG is thought to originate from elements of the periodontal ligament or from the periosteum. Clinically, it appears as a sessile or broadly pedunculated, bluish to purple-red, fleshy or firm swelling with a frequently ulcerated surface. The occurrence of such a lesion may be significant for the prognosis of dental implants, and they can lead to integration failure. Treatment of choice is conservative surgical excision with total removal of the base of the lesion and with curettage of the underlying bone. However, some of these lesions recur. Clinically, it may be difficult to distinguidsh PGCG from pyogenic granuloma. Moreover, also peripheral odontogenic tumors have to be considered in the differential diagnosis of PGCG. The clinical appearance of all these lesions are similar and so the definitive diagnosis is only histological and a biopsy with micreoscopical examination is mandatory.

Direct laser metal sintering as a new approach to fabrication of an isoelastic functionally graded material for manufacture of porous titanium dental implants

OBJECTIVES

This work focuses on a titanium alloy implants incorporating a gradient of porosity, from the inner core to the outer surface, obtained by laser sintering of metal powder. Surface appearance, microstructure, composition, mechanical properties and fractography were evaluated.

METHODS

All the specimens were prepared by a selective laser sintering procedure using a Ti-6Al-4V alloy powder with a particle size of 1-10 microm. The morphological and chemical analyses were performed by SEM and energy dispersive X-ray spectroscopy. The flexure strength was determined by a three-point bend test using a universal testing machine. The surface roughness was investigated using a confocal scanning laser microscope. The surface roughness variation was statistically evaluated by use of a Chi square test. A p value of <0.05 was considered statistically significant.

RESULTS

The original surface microstructure consisted of roughly spherical particles, diameter range 5-50 microm. After exposure to hydrofluoric acid some of these were removed and the microsphere diameter then ranged from 5.1 microm to 26.8 microm. Following an organic acid treatment, particles were replaced by grooves 14.6-152.5 microm in width and 21.4-102.4 microm depth. The metal core consisted of columnar beta grains with alpha and beta laths within the grains. The alloy was composed of 90.08% Ti, 5.67% Al and 4.25% V. The Young's modulus of the inner core material was 104+/-7.7 GPa; while that of the outer porous material was 77+/-3.5 GPa. The fracture face showed a dimpled appearance typical of ductile fracture.

SIGNIFICANCE

In conclusion, laser metal sintering proved to be an efficient means of construction of dental implants with a functionally graded material which is better adapted to the elastic properties of the bone. Such implants should minimize stress shielding effects and improve long-term performance.