Bacterial adherence to silk and expanded polytatrafluorethilene sutures: an in vivo human study

After oral surgery, bacterial adhesion to suture can cause surgical site infections and delay wound healing. Microbial adherence to the suture is influenced by its physical configuration and chemical structure. The aim of this study was to compare in vivo the bacterial adhesion to two suture materials used in oral surgery: silk and monofilament expanded polytetrafluoethilene (e-PTFE). After sinus lift surgery, 15 flaps were sutured with silk (nonabsorbable, organic, braided, 4.0) and 15 were sutured with e-PTFE (nonabsorbable, synthetic, monofilament, 4.0). Seven days after surgery, bacterial adherence, in terms of percentage of the surface covered, was evaluated for each suture material by scanning electron microscope (SEM). Onto silk suture, plaque consisted of a few cocci and a higher proportion of rods and filamentous-shaped bacteria, with some mineralized plaque. Onto e-PTFE speciments, only small colonies of a few cocci or no bacteria were observed, with empty spaces between the colonies and no plaque mineralization. The surface covered by bacteria on e-PTFE specimens was significantly lower than that of silk sutures. (22.1% ±4.96% vs 54.3% ± 7.9%; P =0.0001). The results of the present study suggest that multifilament structure of silk favours a greater bacterial adherence, proliferation, and persistence, so monofilament and e- PTFE suture should be preferred in oral surgery.

Peri-implant disease caused by residual cement around implant-supported restorations: a clinical report

Cement-retained restorations on implants ensures better passive fit and aesthetics, simplicity of fabrication and a homogenous load distribution during function, compared to screw-retained restorations, but it is associated to biological complications following the difficulty to remove cement excess. In fact, residual cement is a predisposing factor to peri-implant tissue inflammation and periimplantitis, because promotes plaque retention of bacteria, due to rough surface. This is especially true since radiographs should not reveal the cement excess and cements commonly used for the cementation of implantsupported prostheses have poor radiodensity. This report documents a case of clinical and radiographic findings of peri-implant disease associated with excess cement extrusion. Two months after cement removal, resolution of inflammation occurred. A good method of cementation, an accessible margin of restoration and the use of ZnOE cement instead of methacrylate cement, should help to prevent cementrelated peri-implant disease.

Compliance of children with removable functional appliance with microchip integrated during covid-19 pandemic: a systematic review

Treatments with removable appliances are widely used in Europe to correct dento-skeletal dysgnatia in the growth phase that is a period of poor cooperation of the patients. Adherence to the wear-time prescription is often not achieved and it represent the main argument against the use of removable devices. Suspected non-compliant behavior with the wear time prescription is often the subject of medico-legal disputes, which can deteriorate doctor-patient relationship. The use of microchips allows to document objectively and clarify the patient's behavior. To conduct a systematic review of the orthodontic literature to identify the factors associated with compliance in orthodontic treatment. We conduct a systematic review that aimed to identity the factors associate with compliance in orthodontic treatment. The main purpose was to assess the objective levels of time of use of the removable appliances and the self-reported levels. A literature search was conducted by the electronic databases PubMed and Cochrane Library. The following search terms were used: compliance functional removable orthodontic appliance. Randomized and nonrandomized controlled trials, prospective cohort studies, case series, qualitative and mixed-methods studies objectively assessing compliance levels were included in the study. A total of 94 articles were identified by PubMed and 14 articles by Cochrane. The papers selected were included for the qualitative analysis and categorized according to the subjects age, the clinical appliance, compliance factors, wear time and monitoring. Removable appliances are an important part of orthodontic treatment, used in growth phase of the patient. Collaboration with removable functional devices determines success / failure in treatment.

Graphene-doped Poly(methyl-methacrylate) as an enhanced biopolymer for medical device and dental implant

Graphene-doping procedure represents a useful procedure to improve the mechanical, physical and biological response of several PMMA-derived polymers and biomaterials for dental applications. The aim of the study was to evaluate measure water sorption, water solubility and tolerance trough the rabbit pyrogen testing pyrogen detection of Graphene doped Poly (methyl methacrylate) (PMMA) compared with PMMA as potential materials for dental implant device. A total of 8 aged and unaged samples Graphene doped PMMA and PMMA were tested for water sorption and water solubility of the specimens. The experimental condition was evaluated according to the ISO 20795-1:2013 protocol. The biopolymer tolerance was evaluated in vivo on animals through the pyrogen detection test, acute intracutaneous and systemic irritation test. After wet conditioning both of Graphene doped PMMA and PMMA reported an increase of the weight. All the experimental samples showed a drastic low level of water sorption and solubility. Graphene doped PMMA unaged specimens showed a stability of physical and optical feature after the treatment. The Graphene doped PMMA has not shown pyrogens, an intradermal and systemic irritant effect on animals. The Graphene-doped PMMA satisfy the standard requirements and provide a physical and optical stability of the compound after the treatment. Further in vivo findings are required for future clinical application of the compound.

Effect of probiotics on the occurrence of nutrition absorption capacities in healthy children: a randomized double-blinded placebo-controlled pilot study

OBJECTIVE

Recent advances in the translational research showed that dietary nutrients have critical importance to the microbioma balance in the gastrointestinal tract. Therefore, the alteration of the intestinal microbiota in order to achieve, restore, and maintain favorable balance in the ecosystem, and the activity of microorganisms present in the gastrointestinal tract is necessary for the improved health condition of the host. The objective of this translational study was to evaluate, in a pediatric population, the efficacy and safety of prophylactic probiotics for a better nutritional absorption capacity in the view to enhance their overall health and immunity.

PATIENTS AND METHODS

A total of 40 pediatric patients between the ages of 14 and 18 years were enrolled in the study and divided under two categories (treated/active group and placebo group). Three-time points clinical evaluations were performed: a baseline assessment (Time 0), a second evaluation at 5 weeks after the start of probiotic use (Time 1), and a final evaluation at the timeline after 10 weeks (Time 2). In the initial phase of the study, the recruited subjects underwent a panel of initial T0 clinical tests. For each of the patients, a blood sample was taken in order to evaluate the following biochemical measurements: Vitamin D, Vitamin A, Calcium, Zinc, and Iron. Moreover, an initial nutritional evaluation was carried out through which the nutritionist estimated the body composition of the subject (weight and body mass index), the caloric needs and dietary behaviour of each recruited patient.

RESULTS

Eligible participants were randomized into placebo (n = 20) or treated/active (n = 20) treatment conditions by random allocation using a computerized random number generator, ensuring all investigators remained blind to the treatment distribution. The data were compared within and between groups using statistical methods. The results confirmed that the probiotic supplementation was effective in increasing the overall blood biomarkers levels of vitamins, calcium, and mineral absorption from baseline to 10 weeks of treatment, compared with the placebo.

CONCLUSIONS

Probiotics may be suggested as supplements to improve biomarkers serum concentration if administered for a period of at least ≥ 5 weeks. However, further studies are required for optimal recommendations in patient treatment.

Steroids and growth factors in oral squamous cell carcinoma: useful source of dental-derived stem cells to develop a steroidogenic model in new clinical strategies

OBJECTIVE

Head and neck region is involved in a high percentage of malignant lesions, and oral squamous cell carcinoma (OSCC) is undoubtedly the most frequently found, accounting for over 90% of malignant tumors. Hormone receptor overexpression, like Estrogen Receptor (ER), Progesterone Receptor (PR) and Endothelial Growth Factor Receptor (EGFR), and signaling have been related to the pathogenesis of OSCC. For metastasis of OSCC, Cancer Stem Cells (CSCs) undergo epithelial to mesenchymal transition (EMT) under the influence of growth factors, cytokines, and regulation of cadherins from the tumor's microenvironment. In this context, the stem cells may become a potential therapeutic target for OSCC through modulation of cytokines and RAS pathway, which is involved in intracell signal transduction. The objective of this study was to suggest an experimental steroidogenic model for OSCC in translational research.

PATIENTS AND METHODS

Dental-derived Stem Cells (D-dSCs) have been obtained from apical papilla tissue that surrounds the developing tooth of healthy donors and cultured in vitro. The cells have been exposed to different concentrations of Estradiol (E2 - 10 nM and 40 nM) in order to verify their response. The number of cells and cell viability has been evaluated up to 96 hours of treatment.

RESULTS

The results showed that cell growth was increased under estradiol treatments compared with cells maintained without estradiol. Moreover, no significant difference in cell death levels was detected among treatments.

CONCLUSIONS

This work underlines as D-dSCs could represent a useful steroidogenic model for the development of the target and gene therapies in OSCC.

Stemness genes expression in naïve vs. osteodifferentiated human dental-derived stem cells

OBJECTIVE

Mesenchymal stem cells (MSCs) have been deeply investigated in regenerative medicine because of their crucial role in tissue healing, such as tissue regeneration. Dental-derived stem cells (d-DSCs) are easily available from dental tissues, which can be isolated from all age patients with minimal discomfort.

PATIENTS AND METHODS

Normal unerupted third molars tooth buds were collected from adolescents' patients underwent to extractions for orthodontic reasons. The expression of the genes Kruppel-like factor 4 (Klf-4), octamer-binding transcription factor 4 (Oct-4), homeobox transcription factor Nanog (NANOG) was investigated in d-DSCs obtained from dental bud (DBSCs), differentiated toward osteoblastic phenotype and not.

RESULTS

Our results showed that DBSCs expressed Oct-4, Nanog, and Klf-4 in undifferentiated conditions and interestingly the expression of such genes increased when the cells were kept in osteogenic medium.

CONCLUSIONS

These attractive stemness properties, together with the effortlessly isolation, during common oral and maxillofacial surgical procedures, from undifferentiated tissues such as dental bud, make this kind of d-DSCs a promising tool in regenerative medicine, having the potential for clinical applications, and reinforcing the present challenge to develop new preventive and healing strategies in tissue regeneration.

A pilot study of human mesenchymal stem cells from visceral and sub-cutaneous fat tissue and their differentiation to osteogenic phenotype

OBJECTIVE

To evaluate the different behavior of two different human adult adipocytes derived stem cells (hASCs) during proliferation and osteogenic differentiation.

PATIENTS AND METHODS

Human adult adipocytes stem cells (hAT-SCs) from visceral (hAV-SCs) and subcutaneous (hAS-SCs) sites were obtained after surgery procedures of seven patients. All samples were fully investigated and the different proliferation rates were evaluated. All MSCs clusters were cultured with an osteogenic and adipogenic differentiation medium. Homogeneous pools of Mesenchymal Stem Cells (MSCs) were confirmed by Flow-Cytometry Analysis (FACS) and Spectrophotometric Assay. The differentiated cells were eventually assessed for the expression of Alkaline Phosphatase (ALP), Alizarin Red (AR) and Oil Red-O (OR-O) detection, and analyzed by the Spectrophotometric Assay. After osteogenic differentiation, the cell clusters were incubated and analyzed with Real Time-Polymerase Chain Reaction (qRT-PCR) and fluorescence microscopy.

RESULTS

The FACS analysis performed on hAT-SCs confirmed the homogenous presence of MSCs in all samples. The ALP, AR stain confirmed the osteogenic differentiation capacity of MSCs towards osteoblast-like-cells. The colorimetric cell metabolic activity (MTS) assay showed an increase in the proliferation rate with different values in both sets hAS-SCs vs. hAV-SCs.

CONCLUSIONS

These in vitro findings of both hAS-SCs and hAV-SCs suggested an important role of these stem cells for future clinical use in bone regeneration. Indeed, the final outcomes suggested a better performance of cells coming from subcutaneous adipose tissue vs. those from visceral fat tissue.

A comparative study on different stemness gene expression between dental pulp stem cells vs. dental bud stem cells

OBJECTIVE

The clinical use of mesenchymal stem cells (MSCs) in regenerative medicine either in tissue repair or tissue reconstruction has given highly interesting results thanks to their particular nature. Sources that have attracted the attention of medical scientists from where stem cells (SCs) in adults could be obtained are different and, dental tissues have certainly become an optimal source of MSCs. Dental tissue is a main reservoir of two types of MSCs dental bud (DBSCs) that constitute the immature precursor of the tooth and dental pulp (DPSCs) that are derived from dental inner pulp and partly from dental follicle tissue and can differentiate into several cell phenotypes as osteoblast, chondrocyte, hepatocytes, cardiomyocytes, neuron and β cells.

PATIENTS AND METHODS

Normal impacted third molars and tooth buds were collected from adults and adolescents underwent to extractions for orthodontic reasons. The expression of the five stemness genes Nanog, OCT4, Sox2, c-Myc and Klf4 were investigated by qRT-PCR in two different dental stem/progenitor cells: dental pulp stem cells (DPSCs) and stem cells from dental bud (DBSCs), differentiated toward osteoblastic phenotype and not.

RESULTS

Both DPSCs and DBSCs are easy to access and we found their expression of the typical mesenchymal stemness makers and osteogenic capacity due to the effective presence of embryonic gene regulators like Nanog, OCT4, Sox2, c-Myc and Klf4. Both DBSCs and DPSCs could represent a valid tool in regenerative medicine and translational applications.

CONCLUSIONS

The results depicted here provide, for the first time to our knowledge, a comparative outcome about the stemness properties generated from accessible tissues such as DPSCs and DBSCs. These two types of SCs showed few different distinctive genetic traits supposedly in relation to their origin, location and stage of maturation. Certainly these SCs reserve solid potential for human clinical application in autologous procedure for bone, hard tissue and soft tissue regeneration, easy to isolate, ready availability, high-biocompatibility and safety and no ethical restrictions.

Liquid biopsy

During the early formation and growth of primary tumor (e.g., breast, colon, or prostate cancer), cells are shed from the primary tumor and then circulate through the bloodstream. Many of the major recent advances in targeted therapies have relied on the acquisition of tumor tissue via biopsy before initiation of therapy or after the onset of resistance. The advantage of physical properties is that they allow circulating tumor cells separation without labelling. Methods based on physical properties include density gradient centrifugation, filtration through special filters. In addition to using somatic point mutations as markers for the detection of tumor DNA, strategies to detect tumor-derived rearrangements and chromosomal copy number changes in the plasma of patients with cancer have been developed. Several studies have shown that metastatic cells might have unique characteristics that can differ from the bulk of cancer cells in the primary tumor currently used for stratification of patients to systemic therapy. In conclusion, the molecular and functional analysis of circulating tumor cells and circulating nucleic acids can be used as companion diagnostics to improve the stratification of therapies and to obtain insights into therapy-induced selection of cancer cells..

Cortical bone lamina approach for mandibular large cystic defect: a case report

This study evaluated the bone healing of the residual cavity after enucleation of mandibular inflammatory cyst by using only a coverage with cortical bone barrier. This study was conducted at the dental clinic of the Medical, Oral and Biotechnology Sciences Department of Chieti in February 2015. A 36-year-old male patient, D.G.M., had a mandibular inflammatory cyst (with a diameter of about 33.9x20.3mm) treated by surgical enucleation, subsequent apicectomy of the elements involved (4.1, 3.1, 3.2, 3.3, 3.4) and coverage of residual defect with a porcine cortical bone barrier (Bone Lamina). Postoperative clinical and radiographic examinations were performed at 3 and 9 months (panoramic radiographs) and at 12 and 24 months (CBCT Dental scan) respectively after cystic enucleation surgery. Uneventful healing and filling of the residual cavity was carried out. The computed analysis of the postoperative radiographs showed bone regeneration of cortical in terms of thickness increase at 12 and 24 months and showed mean values of reduction in size of the residual cavity of 92.1% after 12 months and 96.53% after 24 months. The volume of residual cavity (3123 mm3 in 2015) was seen to decrease (243.6mm3 at 12 months and 108.5 mm3 at 24 months). In this case report the Bone Lamina prevented tissue collapse within the defect and could maintain structural integrity throughout the period required for bone regeneration; it also has the advantage of resorbable membranes, avoiding a second surgery for its removal.

Bone decay and beyond: how can we approach it better

Osseo-degeneration is a disorder related to several factors, that may lead to the disruption of several skeletal regions providing support, such as the femur head, the vertebrae and the alveolar bone. The functional condition can be restored by means of grafting procedures, using different materials: calcium powder, xenografts, ceramics and metals. Such procedures aim at reforming an adequate bone volume and strength, that is necessary to support loading forces. Bone regeneration requires that the basic biological principles of osteogenesis, osteoinduction, osteoconduction and biocompatibility are followed. The success of regenerative procedures may depend on the inner structural, mechanical and metabolic condition of the host's bone on which implants should be inserted, on the surgical technique, and on the biomaterial used. Among these, the aging process of the patient appears to be relevant. It can be associated with metabolic disease leading to systemic functional decay, which involves a gradual steady decline of hormonal, immune function and osteo-metabolic activity. The latter can affect the positive outcomes of bone reconstruction and implant therapy. This review will analyze the biological and physiological factors involved in the bone tissue break-down, such as the influences from gut microbiome unbalance and the consequent metabolic, endocrine, immune dysfunctions, the surgery procedures and the quality of the grafting material used. The decline of bone architecture and strength should be corrected by using an appropriate clinical regenerative approach, based on a bio-endocrine, metabolic and immunologic know-how. The final characteristics of the regenerated bone must be able to support the loading forces transmitted by the implants, independent of the body location, and should be individualized according to the different condition of each patient.

Soft tissue augmentation by means of silicon expanders prior to bone volume increase: a case series

In guided bone regeneration (GBR) interventions, the incorrect manipulation of the soft tissues may lead to exposure of graft due to insufficient amount of tissue needed for a free-tension flap closure. The aim of this investigation was to evaluate the clinical and radiographical effectiveness of soft tissue augmentation in aesthetic areas. A total of 6 patients were treated in the Department of Medical, Oral and Biotechnological Sciences, University "G. D'Annunzio" of Chieti-Pescara, with a radiographical follow-up at 1 year from the loading. At the follow up, no soft tissue dehiscence was observed This study presented an innovative approach for soft tissue augmentation prior to bone regeneration in aesthetic areas. Augmentation of soft tissue with a silicon expander device before bone regeneration is a simple technique and also allows to obtain greater bone tissue in selective cases.

Hyaluronic acid fillers in lip augmentation procedure: a clinical and histological study

Several approaches have been proposed for soft tissue augmentation using injectable materials for lip and soft-tissue augmentation due to their physical and biological properties. Hyaluronic acid represents a natural component of the connective tissues, related to wound healing and skin regeneration. The aim of this research was to investigate the clinical and histological effectiveness of cross-linked hyaluronic acid for lip augmentation. A total of 8 patients were treated for lip augmentation with a clinical follow up of 60 days. After this period a histological evaluation was performed to evaluate the healing of the treated regions. The healing phase reported no inflammatory response, tissue contractions and no local flogistic evidence in the treated areas, where the filling volume appeared maintained. The 60 days histological evaluation showed evidence of filler resorption with few infiltrated inflammatory cells. The clinical and histological findings suggested that cross-linked hyaluronic acid represents a safe and effective tool for lip augmentation.

Evaluation of the effectiveness and safety of peppermint peel (PMP) soft peeling for skin ageing

Turning to peeling in a dermatological sphere is extensively common and has been used for a long time. From the use of single acids moving on to the so-called compound peelings (associations of more than one substance in the same product) and the combined peelings which take advantage of the action of different substances in a synergistic manner (different products are applied sequentially) in order to best guarantee a greater effectiveness of the treatment for the recommended target. Superficial peelings, combined and not, have led to a drastic reduction in the percentage of incidence of adverse events typical of medium and deep peels. Nevertheless, it has been demonstrated that superficial peels bring about a rejuvenating effect through the mechanical stimulation of the Skin Stress Response System (SSRS), system designated to repairing the damaged tissue and restoring of the normal homeostasis. Clinical trials aims to evaluate the effectiveness and safety of the peppermint peel (PMP) medical device in subjects with different ageing expressions both in qualitative terms (different blemishes such as discolouration, fine wrinkles, elastosis, atony and skin inelasticity, laxity, scarce superficial hydration) and in quantitative terms (degree, extension and number of lesions). A non-controlled multi-centric clinical trial was done in 121 subjects. The use protocol calls for a session every 2 weeks for a total of 4 sessions. Subjects were evaluated before each subsequent session at the first and at 2-4-8 weeks of the fourth and last treatment. During the study there were no adverse events. Only a minimal scurfy flaking and a very slight redness were reported. From an effectiveness point of view, the percentage of therapeutic failure, judged with a score equal to or greater than 4 or 5 in Global Aesthetic Improvement Scale (GAIS) scale was 0%. Best score was obtained in subjects ranging in ages between 38 and 57 (2.02) and in women (2.02) years, while the less satisfactory one was obtained in males (2.14). The study has demonstrated that PMP and the proposed protocol are effective and safe to treat subject with skin signs of chrono and photo ageing, thanks to its capabilities of carrying out a mechanic action indicated as a coadjuvant in the treatment of the dermoepidermic revitalisation through chemical exfoliation and hydration.

Non-surgical treatment of lower eyelid fat pads with an injectable solution acid deoxycholic based

The use of sodium deoxycholate (DC) in aesthetic medicine for reducing unwanted localized fat deposits is a procedure in use for over 30 years. Lower eyelid fat pads are one of the main imperfections of the middle third of the face. The purpose of the study is to assess the effectiveness and the safety of a second-generation injectable solution containing sodium deoxycholate 1.25% (DB125) for the treatment of lower eyelid fat pads. A multi-centre observational prospective study was carried out between May and October 2017. Patients presented various forms and degrees of lower eyelid fat pads. They were treated montly apart until the clinical result was obtained. The technique was explained. The study treated 120 patients for a total of 306 infiltration sessions (average 2.55 per patient). Patients gave the effectiveness of the treatment an average score of 7.125 (7.28 in men and 7.03 in women). The greatest successes were in patients under the age of 40. The medical evaluation showed therapeutic success in 85.83%. Adverse events were reported. The results of the study are encouraging since they have shown a therapeutic success from both the viewpoint of specialist medical assessment and from the personal, subjective view of the patients treated. This success did not show any significant differences between sex. On the other hand, outcome has been better in the younger age groups. The high degree of effectiveness shown in the study was associated with a minimal occurrence of adverse events. Therefore DB125, used with the right technique and dosage, is effective and safe to treat lower eyelid fat pads.

Narrow single tooth implants for congenitally missing maxillary lateral incisors: a 5-year follow-up

INTRODUCTION

The maxillary lateral incisor epidemiologically represents the second most common congenitally absent teeth. In literature, different approaches have been proposed, such as canine teeth substitution, traditional prosthetic rehabilitation, adhesive restoration or single-tooth implant. The aim of this investigation was to evaluate the clinical and radiographical effectiveness of narrow single tooth implant treatment for missing maxillary lateral incisors.

MATERIALS AND METHODS

A total of 11 subjects, in seven cases bilaterally, were treated in the Department of Medical, Oral and Biotechnological Sciences, University "G. D'Annunzio" of Chieti-Pescara, with a radiographical follow-up at 5 years from the loading.

RESULTS

At the follow up, no bone defects or pathological gingival probing were present around the peri-implant tissues. No mechanical complications, such as loss of the crown fixation screws or fracture, were reported.

CONCLUSIONS

Narrow implants represent a predictable optional treatment for maxillary lateral incisor restoration, with a high-level aesthetic and functional outcome of the rehabilitation.

Drug-induced gingival overgrowth: an in vitro study on cyclosporine and human gingival fibroblasts

Gingival overgrowth is a serious side-effect that accompanies the use of cyclosporine. Up to 97% of the patients submitted to immunosuppressant drugs have been reported to suffer from this side-effect. Several conflicting theories have been proposed to explain the fibroblast's function in gingival overgrowth. To determine whether cyclosporine alter the inflammatory responses, we investigated its effects on gingival fibroblast gene expression as compared with untreated cells. Fragments of gingival tissue of healthy volunteers (11-year-old man, 68-year-old-woman and 20-year-old-man) were collected during operation. Cells were incubated with cyclosporine and gene expression of 29 was investigated in gingival fibroblasts cell culture, compared with untreated cells. The gene expression level was significantly deregulated only for 10 genes (CCL1, CCR1, CCR4, CCR5, CCR10, IL1A, IL1B, IL5, IL6R and TNFSF10) that were found to be downregulated except for TNFSF10. These results seem to demonstrate that cyclosporine has no inflammatory effect on healthy gingival fibroblast. In the future, it would be interesting understand, the possible effect of the drug on inflammation of patients affected by gingival hyperplasia.

In vitro interface changes of two vs three narrow-diameter dental implants for screw-retained bar under fatigue loading test

The mechanical failure of a dental implant is clinically related to a prosthetic overload dissipated on the fixture/abutment complex. The aim of this investigation was to evaluate the fracture strength of two vs three narrow-diameter dental implant configurations for screw-retained bars. Different configurations of screw-retained bars on two narrow-diameter dental implants (Group I) and screw-retained bars on three narrow-diameter dental implants (Group II) were tested under a static fracture loading. A total of 20 specimens, 10 for each group were evaluated. The fracture loading point was significatively higher in Group I (p<0.05). The experimental groups reported high levels of fracture strength under loading that encourages the clinical application of screw-retained bars supported by multiple narrow-diameter implants.

Complication in third molar extractions

Mandibular third molars (MM3s) are responsible for pericoronitis, primary and/or secondary crowding of the dentition, odontogenic tumors and cysts, periodontal defects associated with the posterior part of mandibular second molars. Tooth extraction is indicated for prophylactic and therapeutic purpose in patients with problems caused by impacted teeth. Common postoperative complications associated with third molar extraction are alveolitis (0.5e32.5%), infection (0.9e4.2%), postoperative bleeding (0.2e1.5%), transient dysfunction of the inferior alveolar nerve (0.6e5.5%), and permanent dysfunction of the inferior alveolar nerve (0.1e0.9%). A literature review reveals number of individual case reports of accidental displacement to various anatomical locations, namely, the infratemporal fossa, pterygomandibular space, lateral pharyngeal space, submandibular space, and sublingual space.

A 10-year retrospective comparative human study on screw-retained versus cemented dental implant abutments

The aim of this 10-year retrospective study was to evaluate the long-term reliability, survival rate and mechanical and biological complications of single-crown implant rehabilitations with two different types of fixture-abutment connections: screw-retained abutments (SRAs) with internal hexagonal connection, and cemented retained abutments (CRAs). A total of 300 single implant-supported crowns were analysed, which had been inserted between 2004 and 2007. Patients were classified according to two groups: the SRA group (n = 150) and the CRA group (n = 150). The primary outcome was marginal bone loss (MBL) on peri-apical radiographs. Bleeding on probing (BOP) and probing depth (PD) were also evaluated. Moreover, prosthetic complications were recorded. Analysis of variance (ANOVA) was used to evaluate the differences between the groups. The overall implant failure rate was 4.2%. The overall positive BOP index was 81.9% of the sites under investigation, as 83.4% for SRA and 80.4% for CRA. Moreover, >5 mm PD demonstrated a rate of 21.0% for CRA, and 13.8% for SRA. The primary outcome of mean MBL was 2.09±1.07 mm for SRA and 1.54±1.20 mm for CRA. Analysis of variance of MBL showed statistical significance for the difference between these two groups (P less than 0.001). For the mechanical aspects, an overall 12.5% of complications occurred. No implant or abutment fractures were recorded. Although complications occurred, the results from this 10-year retrospective study show that these two methods have positive long-term follow-up. With MBL significantly greater for the SRA group than the CRA group, the clinical use of CRA is encouraged in terms of the lower bone resorption rate.

A novel technique to prevent sinus membrane collapse during maxillary sinus floor augmentation without bone graft: technical note

Different surgical techniques have been developed to reconstruct the posterior maxilla without bone graft. A barrier membrane usually placed internal to the sinus, without stabilizer or bone window, pushed inside the sinus cavity as the ''roof'' of the sinus cavity to preserve the space and help bone regeneration has been used with success. In the present technical report, the heterologous cortical lamina is used for the mechanical support of sinus membranes. The membrane is placed through two lines of 2-3 mm, mesial and distal, created at the top of the antrostomy. The half heterologous membrane is positioned on these lines and pushed to the nose wall of the sinus, and the other half is folded to cover the window. In this way the bone lamina is stable. Cone Beam Computed Tomography was used to evaluate the efficacy of bone lamina to preserve the space in sinus lifting which contributes positively to wound healing and is effective in bone formation without biomaterials.