A critical analysis of research methods and experimental models to study biocompatibility of endodontic materials.

Materials used for endodontics and with direct contact to tissues have a wide range of indications, from vital pulpal treatments to root filling materials and those used in endodontic surgery. In principle, interaction with dental materials may result in damage to tissues locally or systemically. Thus, a great variety of test methods are applied to evaluate a materials' potential risk of adverse biological effects to ensure their biocompatibility before commercialization. However, the results of biocompatibility evaluations are dependent on not only the tested materials but also the test methods due to the diversity of these effects and numerous variables involved. In addition, diverse biological effects require equally diverse assessments on a structured and planned approach. Such a structured assessment of the materials consists of four phases: general toxicity, local tissue irritation, pre-clinical tests and clinical evaluations. Various types of screening assays are available; it is imperative to understand their advantages and limitations to recognize their appropriateness and for an accurate interpretation of their results. Recent scientific advances are rapidly introducing new materials to endodontics including nanomaterials, gene therapy and tissue engineering biomaterials. These new modalities open a new era to restore and regenerate dental tissues; however, all these new technologies can also present new hazards to patients. Before any clinical usage, new materials must be proven to be safe and not hazardous to health. Certain international standards exist for safety evaluation of dental materials (ISO 10993 series, ISO 7405 and ISO 14155-1), but researchers often fail to follow these standards due to lack of access to standards, limitation of the guidelines and complexity of new experimental methods, which may cause technical errors. Moreover, many laboratories have developed their testing strategy for biocompatibility, which makes any comparison between findings more difficult. The purpose of this review was to discuss the concept of biocompatibility, structured test programmes and international standards for testing the biocompatibility of endodontic material biocompatibility. The text will further detail current test methods for evaluating the biocompatibility of endodontic materials, and their advantages and limitations.

Specialized pro-resolving lipid mediators in endodontics: a narrative review.

Endodontics is the branch of dentistry concerned with the morphology, physiology, and pathology of the human dental pulp and periradicular tissues. Human dental pulp is a highly dynamic tissue equipped with a network of resident immunocompetent cells that play major roles in the defense against pathogens and during tissue injury. However, the efficiency of these mechanisms during dental pulp inflammation (pulpitis) varies due to anatomical and physiological restrictions. Uncontrolled, excessive, or unresolved inflammation can lead to pulp tissue necrosis and subsequent bone infections called apical periodontitis. In most cases, pulpitis treatment consists of total pulp removal. Although this strategy has a good success rate, this treatment has some drawbacks (lack of defense mechanisms, loss of healing capacities, incomplete formation of the root in young patients). In a sizeable number of clinical situations, the decision to perform pulp extirpation and endodontic treatment is justifiable by the lack of therapeutic tools that could otherwise limit the immune/inflammatory process. In the past few decades, many studies have demonstrated that the resolution of acute inflammation is necessary to avoid the development of chronic inflammation and to promote repair or regeneration. This active process is orchestrated by Specialized Pro-resolving lipid Mediators (SPMs), including lipoxins, resolvins, protectins and maresins. Interestingly, SPMs do not have direct anti-inflammatory effects by inhibiting or directly blocking this process but can actively reduce neutrophil infiltration into inflamed tissues, enhance efferocytosis and bacterial phagocytosis by monocytes and macrophages and simultaneously inhibit inflammatory cytokine production. Experimental clinical application of SPMs has shown promising result in a wide range of inflammatory diseases, such as renal fibrosis, cerebral ischemia, marginal periodontitis, and cancer; the potential of SPMs in endodontic therapy has recently been explored. In this review, our objective was to analyze the involvement and potential use of SPMs in endodontic therapies with an emphasis on SPM delivery systems to effectively administer SPMs into the dental pulp space.

Association of vitamin D binding protein and vitamin D receptor gene polymorphisms in Iranian patients with chronic periodontitis.

Chronic periodontitis (CP) is a multifactorial disease and the most common type of periodontitis mainly caused by microbial plaque. Insufficient oral hygiene may initiate CP and it can be further modified and progressed by environmental and genetic susceptibilities. The aim of the present study was to investigate the association between VDBP (rs7041 and rs4588) and (Taq 1-rs7975232 and Apa1-rs731236) SNPs of VDR gene receptor and susceptibility to CP in an Iranian population. Sixty nine cases with diagnosis of CP and 78 matched healthy controls engaged in this study. Three-milliliter peripheral blood samples were obtained for DNA isolation. Genotype analysis was performed using restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR). Chi-squared test was used for distribution of genotypes analysis. 95% confidence interval (CI) was used to calculate the odds ratio (OR). Deviation from Hardy-Weinberg equilibrium, multiple inheritance models, linkage disequilibrium and haplotype analysis were done. There was no significant association between genotype/phenotype of VDBP's SNPs (rs7041 and rs4588) and occurrence of chronic periodontitis (p value = 0.401) Moreover, no statistically significant association was found between chronic periodontitis and Taq1 (rs731236) (p value = 0.401) and Apa1 (rs7975232) (p value = 0.248). The analysis of alleles and genotypes' distribution between different severities of chronic periodontitis and healthy controls indicated a significant association between various severities of chronic periodontitis and Apa1 (rs7975232) (p value = 0.011) and VDBP's SNPs (rs7041 and rs4588) (p value = 0.038), whereas no statistically significant association was observed between various severities of chronic periodontitis and Taq1 (rs731236) (p value = 0.278). Our results suggest a significant association between severity of chronic periodontitis and Apa1 (rs7975232) and VDBP SNPs (rs7041 and rs4588). Sequencing studies on different populations may release other results due to the genetic and racial diversity.

Buccal Fat Pad-Derived Stem Cells in Three-Dimensional Rehabilitation of Large Alveolar Defects: A Report of Two Cases.

This case report seeks to describe efficient clinical application of adipose-derived stem cells (AdSCs) originated from buccal fat pad (BFP) in combination with conventional guided bone regeneration as protected healing space for reconstruction of large alveolar defects after extraction of multiple impacted teeth. The first case was a 19-year-old woman with several impacted teeth in the maxillary and mandibular regions, which could not be forced to erupt and were recommended for surgical extraction by the orthodontist. After this procedure, a large bone defect was created, and this space was filled by AdSC loaded natural bovine bone mineral (NBBM), which was protected with lateral ramus cortical plates, microscrews, and collagen membrane. After 6 months of post-guided bone regeneration, the patient received 6 and 7 implant placements, respectively, in the maxilla and mandible. At 10 months postoperatively, radiographic evaluation revealed thorough survival of implants. The second case was a 22-year-old man with the same complaint and large bony defects created after his teeth were extracted. After 6 months of post-guided bone regeneration, he received 4 dental implants in his maxilla and 7 implants in the mandible. At 48 months postoperatively, radiographs showed complete survival of implants. This approach represented a considerable amount of 3-dimensional bone formation in both cases, which enabled us to use dental implant therapy for rehabilitation of the whole dentition. The application of AdSCs isolated from BFP in combination with NBBM can be considered an efficient treatment for bone regeneration in large alveolar bone defects.

A modified frenectomy technique: a new surgical approach.

The frenum is a mucosal fold that attaches the lips or cheeks to the alveolar mucosa, gingiva, and underlying periosteum. Consequences of an abnormal frenal attachment include gingival recession, decreased vestibular depth, decreased range of lip movement, and involvement of interdental papilla, causing a diastema. Several methods to eliminate ectopic frenal attachments have been suggested, including frenectomy (elimination) and frenotomy (repositioning). This case report describes the use of a modified frenectomy technique in a 15-year-old girl with excess gingiva between the maxillary central incisors, which exhibited a 3-mm diastema. First, a semilunar primary incision was made in the palatal surface at a 5-mm distance from the tip of the papilla. Next, sulcular incisions were made around the tooth, and the papilla was transposed to the buccal via a papilla preservation flap. After complete elimination of frenal attachments in the bone, the flap was repositioned and sutured to the palatal surface. Afterward, the frenum was classically cut and sutured. Through this approach, the position of the frenum was changed apically without invading the papilla. At the 3-month follow-up, it was found that the modified technique (combination of papilla preservation flap and frenotomy) had minimized the surgical scar on the buccal surface, preserved the papilla, and yielded optimal esthetic results.

Timing of soft tissue management around dental implants: a suggested protocol.

Survival of dental implants depends on several factors; soft tissue (ST) management around dental implants is one of the foremost. Several studies have suggested techniques for ST management around dental implants, but none of them has discussed a suitable timetable for this process. This study aimed to review published articles related to the timing of ST management around dental implants and suggest a customized treatment protocol. A search of the PubMed database was conducted; the search was limited to English-language articles published from January 1995 to July 2015 with available full texts. Only in vivo studies and clinical trials in relation to the terms soft tissue management, management timing, keratinized mucosa, free gingival graft, connective tissue graft, soft tissue, augmentation, and dental implant were included. A total of 492 articles were reviewed, and eventually 42 articles were thoroughly evaluated. Those with treatment protocols in terms of the timing of ST grafting were selected and classified. ST management around dental implants may be done prior to the surgical phase, after the surgical phase, before loading, or even after loading. A thick gingival biotype is more suitable for implant placement, providing more favorable esthetic results. A treatment plan should be based on individual patient needs as well as the knowledge and experience of the clinician. The width and thickness of keratinized tissues, the need for bone management, and local risk factors that influence esthetic results determine the appropriate time for ST augmentation procedures.

Plasma Level Formaldehyde in Children Receiving Pulpotomy Treatment under General Anesthesia.

OBJECTIVES: Formocresol has long been used by dentists for pulpotomy of primary teeth. Due to some concerns regarding its possible carcinogenicity, formocresol has been the topic of numerous studies. This study sought to assess the changes in plasma level of formaldehyde of children after receiving pulpotomy under general anesthesia. STUDY DESIGN: Twenty-five children between 2-6 years requiring dental treatments under general anesthesia were studied. Blood samples were taken of children before and after the procedure. Plasma level of formaldehyde was measured using high performance liquid chromatography (HPLC). RESULTS: A total of 106 pulpotomy treatments were performed in 25 children using 126 cotton pellets dipped in formocresol. An increase and a decrease in plasma level of formaldehyde were noted in 5 (20%) and 20 (80%) children, respectively post-operatively compared to baseline. The t-test showed no significant difference in plasma level of formaldehyde pre- and postoperatively (P=0.12). the plasma level of formaldehyde in children who had higher levels of formaldehyde prior to the operation was also higher than that of others after the operation and this association was statistically significant (P=0.001, r=0.64). CONCLUSIONS: The results showed no significant change in the mean plasma level of formaldehyde in children who received pulpotomy under general anesthesia compared to its baseline value.

Feeding in Oral Cancer Patients After Massive Ablative Surgery: Percutaneous Endoscopic Gastrostomy or Nasogastric Tube.

Feeding after ablative oral cancer surgery is a major concern in postoperative care phase. The aim of this study was to compare postoperative phase of healing in patients undergoing nasogastric tube insertion and percutaneous endoscopic gastrostomy. In this single randomized clinical trial, 40 patients were randomly allocated to 2 groups according to a randomized list: group one (20 patients) had nasogastric tube for 4 weeks and group two (20 patients) underwent percutaneous endoscopic gastrostomy for 4 weeks or more after the surgery. Occurrence of infection and wound dehiscence was assessed. Weight loss was defined as reduction in patients' weight at 4 weeks after the surgery compared with preoperation. Weight loss was 7.9 ±â€Š1.91 kg in group one and 5.3 ±â€Š1.38 kg in group two; the difference in this regard between the 2 groups was statistically significant (P = 0.001). In group one, 10 subjects had dehiscence versus 3 subjects in group two; this difference was significant (P = 0.04). Analysis of the data demonstrated a significant difference in postsurgical infection between the 2 groups (P = 0.044). It seems that gastrostomy may be an appropriate method for feeding in patients with extensive oral cancer.

Immunomodulatory Effects of Endodontic Sealers: A Systematic Review.

Inflammation is a crucial step prior to healing, and the regulatory effects of endodontic materials on the immune response can influence tissue repair. This review aimed to answer whether endodontic sealers can modulate the immune cells and inflammation. An electronic search in Scopus, Web of Science, PubMed, and Google Scholar databases were performed. This systematic review was mainly based on PRISMA guidelines, and the risk of bias was evaluated by SYRCLEs and the Modified CONSORT checklist for in vivo and in vitro studies, respectively. In total, 28 articles: 22 in vitro studies, and six in vivo studies were included in this systematic review. AH Plus and AH 26 can down-regulate iNOS mRNA, while S-PRG sealers can down-regulate p65 of NF-κB pathways to inhibit the production of TNF-α, IL-1, and IL-6. In vitro and in vivo studies suggested that various endodontic sealers exhibited immunomodulatory impact in macrophages polarization and inflammatory cytokine production, which could promote healing, tissue repair, and inhibit inflammation. Since the paradigm change from immune inert biomaterials to bioactive materials, endodontic materials, particularly sealers, are required to have modulatory effects in clinical conditions. New generations of endodontic sealers could hamper detrimental inflammatory responses and maintain periodontal tissue, which represent a breakthrough in biocompatibility and functionality of endodontic biomaterials.

Dentinal Tubule Penetrability and Bond Strength of Two Novel Calcium Silicate-Based Root Canal Sealers.

BACKGROUND: Once the chemo-mechanical preparation of root canals is finished, achieving a complete seal of the root canal system becomes crucial in determining the long-term success of endodontic treatment. The important goals of root canal obturation are to minimize leakage and achieve an adequate seal. Thus, a material that possesses satisfactory mechanical characteristics, is biocompatible, and has the ability to penetrate the dentine tubules adequately is needed. AIM: This study aimed to compare the penetrability and bond strength between two calcium silicate-based sealers and an epoxy resin-based sealer, as well as examine the relationship between penetrability and bond strength for the different sealers. METHOD AND MATERIALS: Thirty-nine recently extracted single-rooted human premolar teeth were instrumented and divided evenly into three groups (n = 13), according to the sealer used for obturation: AH Plus Jet, EndoSequence, and AH Plus Bioceramic Sealer. Three teeth (30 slices) were randomly selected out of each for analysis using confocal laser scanning microscopy to assess penetrability. The remaining ten teeth (90 slices) in each group were subject to push-out tests using a universal testing machine. All teeth were sectioned into nine transverse slices of 0.9 mm thickness for their respective tests (apical, middle, coronal). RESULTS: AH Plus Jet exhibited significantly lower penetrability and significantly higher bond strength compared to EndoSequence BC sealer (p = 0.002) and AH Plus Bioceramic Sealer (p = 0.006). There was no significant difference between EndoSequence BC sealer and AH Plus Bioceramic Sealer in terms of either penetrability or bond strength. No correlation was found between penetrability and bond strength. CONCLUSIONS: Within the limitation of this study and regardless of the location in the canal, the bioceramic based root canal sealers appeared to perform better than the epoxy resin-based sealer in terms of dentinal penetration rate. Further studies are required to compare other biomechanical properties of bioceramic sealers including setting characteristics and bacterial leakage.

Modulating Osteoimmune Responses by Mesoporous Silica Nanoparticles.

The immune response plays an important role in biomaterial-mediated osteogenesis. Nanomaterials may influence immune responses and thereby alter bone regeneration. Mesoporous silica nanoparticles (MSNs) have received much attention for drug delivery and bone regeneration. Recently, immunomodulatory effects of MSNs on osteogenesis have been reported. In this Review, we summarize the osteoimmunomodulation of MSNs, including the effects of MSN characteristics on immune cells and osteogenesis. Impacts of MSNs on immune cells vary according to nanoparticle properties, including surface topography and charge, particle size, and ion release. MSNs with suitable doses can inhibit inflammation and create an immune microenvironment beneficial for bone regeneration by activating immune cells and stimulating cytokine release. Further work is needed to explore and clarify the underlying mechanisms, including crosstalk between various types of immune cells and how to design MSNs to create a suitable immune environment for osteogenesis.

Impact of photobiomodulation using four diode laser wavelengths of on cationic liposome gene transfection into pre-osteoblast cells.

Gene therapy can be an effective treatment modality for some severe genetic diseases. Despite efforts to improve their performance, non-viral gene delivery methods remain inefficient and costly. As an alternative to viral vectors, cationic liposomes have a good safety profile and low immunogenicity, but relatively low transfection efficiency. They may also be toxic to cells at high concentrations. Given these challenges, the present study explored the impact of photobiomodulation (PBM) on cationic liposome plasmid DNA transfection in terms of its efficiency and toxicity, using Lipofectamine 2000 to carry green fluorescent protein (GFP) encoding plasmid DNA, with the pre-osteoblast MC3T3-E1 cell line as the target. Cultures were irradiated using diode lasers (445, 685, 810, or 970 nm) at 200 mW using pulsed mode (50 Hz), with a power density of 104.64 mW/cm2, and irradiance from 6 to 18 joules. To determine transfection efficiency, expression of GFP was assessed using confocal laser scanning microscopy and flow cytometry. Cell viability was evaluated using the MTT assay. PBM using 810 nm and 970 nm lasers significantly enhanced transfection efficiency for GFP, indicating more efficient uptake of plasmid DNA. Conversely, laser irradiation at 445 nm and 685 nm wavelengths reduced the GFP transfection efficiency. Treatment using 685, 810, and 970 nm lasers at 12 J maintained cell viability and prevented toxicity of cationic liposomes. Overall, these findings support the concept that PBM using near infrared laser wavelengths can enhance transfection efficiency and support cell viability when cationic liposomes are used as the vector in gene therapy.

Efficient transfection and long-term stability of rno-miRNA-26a-5p for osteogenic differentiation by large pore sized mesoporous silica nanoparticles.

MicroRNA (miRNA) based therapy for bone repair has shown promising results for regulating stem cell proliferation and differentiation, an efficient and stable vector for delivery of microRNA delivery is needed. The present study explored the stability and functionality of lyophilized mesoporous silica nanoparticles with core-cone structure and coated with polyethylenimine (MSN-CC-PEI) as a system for delivering Rattus norvegicus (rno)-miRNA-26a-5p into rat marrow mesenchymal cells (rBMSCs) to promote their osteogenic differentiation. We assessed the cellular uptake and transfection efficiency of nanoparticles loaded with labelled miRNA using confocal laser scanning microscopy and flow cytometry, and the cell viability using the MTT assay. The expression levels of osteogenic genes after one and two weeks were analysed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Extracellular matrix deposition and mineralization at 3 weeks were evaluated using Picro Sirius red and Alizarin red staining. We also assessed the performance of the delivery system after long term storage, by freeze drying rno-miRNA-26a-5p@MSN-CC-PEI with 5% trehalose and keeping them at -30 °C for 3 and 6 months. Osteogenic differentiation, matrix deposition, and mineralization were all significantly increased by rno-miRNA-26a-5p. In addition, this enhancement was not significantly altered by lyophilization and storage. Overall, these findings support the concept of MSN-CC-PEI as a delivery system for gene therapy. The complex of rno-miRNA-26a-5p@MSN-CC-PEI could efficiently transfect rBMSCs and enhance their osteogenic differentiation. In addition, the lyophilized complexes remain functional after 6 months of storage.

Microbial Decontamination and Antibacterial Activity of Nanostructured Titanium Dental Implants: A Narrative Review.

Peri-implantitis is the major cause of the failure of dental implants. Since dental implants have become one of the main therapies for teeth loss, the number of patients with peri-implant diseases has been rising. Like the periodontal diseases that affect the supporting tissues of the teeth, peri-implant diseases are also associated with the formation of dental plaque biofilm, and resulting inflammation and destruction of the gingival tissues and bone. Treatments for peri-implantitis are focused on reducing the bacterial load in the pocket around the implant, and in decontaminating surfaces once bacteria have been detached. Recently, nanoengineered titanium dental implants have been introduced to improve osteointegration and provide an osteoconductive surface; however, the increased surface roughness raises issues of biofilm formation and more challenging decontamination of the implant surface. This paper reviews treatment modalities that are carried out to eliminate bacterial biofilms and slow their regrowth in terms of their advantages and disadvantages when used on titanium dental implant surfaces with nanoscale features. Such decontamination methods include physical debridement, chemo-mechanical treatments, laser ablation and photodynamic therapy, and electrochemical processes. There is a consensus that the efficient removal of the biofilm supplemented by chemical debridement and full access to the pocket is essential for treating peri-implantitis in clinical settings. Moreover, there is the potential to create ideal nano-modified titanium implants which exert antimicrobial actions and inhibit biofilm formation. Methods to achieve this include structural and surface changes via chemical and physical processes that alter the surface morphology and confer antibacterial properties. These have shown promise in preclinical investigations.

Photobiomodulation in Temporomandibular Disorders.

Objective: This systematic review aimed to comprehensively review all available documents regarding photobiomodulation therapy (PBMT) application in temporomandibular disorder (TMD) patients and to suggest an evidence-based protocol for therapeutic PBM administration for these patients. Background data: The existence of temporomandibular joint and/or pain and dysfunction in masticatory muscles is characterized in TMDs. PBMT is, due to its impact on biological processes, especially inflammation, considered as an adjuvant treatment modality in TMD cases. Materials and methods: All original articles related to PBMT for TMDs in EMBASE, MEDLINE (NCBI PubMed and PMC), Cochrane library, Scopus, Web of Science, and Google Scholar were reviewed until December 2018. Results: The energy density ranging from 0.75 to 112.5 J/cm2 with 0.9-500 mW power was found to be a window protocol for light application. The best results for pain relief and mandibular movement enhancement were reported after application of GaAlAs diode laser, 800-900 nm, 100-500 mW, and <10 J/cm2, twice a week for 30 days on trigger points. The session of light applications varied from 1 to 20. Conclusions: Although most articles showed that PBMT is effective in reducing pain and contributed to functional enhancement in TMD patients, the heterogenic parameters that have been reported in various studies made the standardization of PBMT complicated. However, such evidence-based consensus can be beneficial for both future research and for clinical applications.

Photobiomodulation in Oral Surgery: A Review.

Objective: This article presents a review of current data on the applications of photobiomodulation (PBM) in the field of oral and maxillofacial surgery (OMFS), to guide future research. Background data: Photobiomodulation therapy (PBMT) has been reported to be effective for various postoperative conditions, including pain relief, improvement of mastication, neurosensory recovery, and wound healing. There is a need for identifying the therapeutic irradiation windows for these conditions, based upon the available literature. Materials and methods: All original articles related to PBM for oral surgery in MEDLINE (NCBI PubMed and PMC), EMBASE, Scopus, Cochrane library, Web of Science, and Google Scholar were reviewed until December 2018. Results: Forty-six clinical trials were included in this study. These trials were categorized into three different types of PBM applications. After reviewing all these studies, the most effective physical properties for PBM pain reduction after tooth extraction were as follows: wavelength 650-980 nm; power 4-300 mW; and energy density 3-85.7 J/cm2. PBMT at 660-910 nm with 4-500 mW power and 2-480 J/cm2 energy density was effective for decreasing facial swelling. At the same wavelength and power range with 4-106 J/cm2 energy density, PBM was effective for alleviating trismus after tooth extraction. Conclusions: Most papers suggested that PBM seemed to be effective in reducing pain, swelling, and trismus after third molar tooth extraction, neurosensory and nerve recovery after mandibular ramus osteotomy. The heterogeneity of the standardization regarding the parameters of laser calls for caution in interpretation of these results. However, this evidence-based review regarding the best protocols for OMFS applications can be beneficial for both future research and clinical applications.

Buccal fat pad-derived stem cells with anorganic bovine bone mineral scaffold for augmentation of atrophic posterior mandible: An exploratory prospective clinical study.

BACKGROUND: Application of adipose-derived stem cells originated from buccal fat pad (BFP) can simplify surgical procedures and diminish clinical risks compared to large autograft harvesting. PURPOSE: This study sought to evaluate and compare the efficacy of buccal fat pad-derived stem cells (BFPSCs) in combination with anorganic bovine bone mineral (ABBM) for vertical and horizontal augmentation of atrophic posterior mandibles. MATERIALS AND METHODS: Fourteen patients with atrophic posterior mandible were elected for this prospective exploratory study. BFP (3-5 mL) was harvested and BFPSCs were isolated and combined with ABBM at 50% ratio. The vertical and horizontal alveolar deficiencies were augmented by 50% mixture of ABBM with either BFPSCs (group 1) or particulated autologous bone (group 2). Titanium mesh was contoured to the desired 3D shape of the alveolar ridge and fixated to the host sites over the graft material of the two groups. At first, the amount of new bone areas was calculated by quantitative analysis of cone beam computed tomography (CBCT) images that were taken 6 months postoperatively according to regenerative techniques (group 1 vs group 2 without considering the type of bone defects). Second, these amounts were calculated in each group based on the type of defects. RESULTS: Quantitative analysis of CBCT images revealed the areas of new bone formation were 169.5 ± 5.90 mm2 and 166.75 ± 10.05 mm2 in groups 1 and 2, respectively. The area of new bone formation for vertical defects were 164.91 ± 3.74 mm2 and 169.36 ± 12.09 mm2 in groups 1 and 2, respectively. The area of new bone formation for horizontal deficiencies were 170.51 ± 4.54 mm2 and 166.98 ± 9.36 mm2 in groups 1 and 2, respectively. There were no statistically significant differences between the two groups in any of the pair-wise comparisons (P > 0.05). CONCLUSIONS: The findings of the present study demonstrated lack of difference in bone volume formation between BFPSCs and autologous particulate bone in combination with ABBM. If confirmed by future large-scale clinical trial, BFPSCs may provide an alternative to autogenous bone for reconstruction of alveolar ridge defects.

Impact of malocclusion severity on oral health-related quality of life in an Iranian young adult population.

OBJECTIVE: This study aimed to assess the relationship between malocclusion severity and oral health-related quality of life (QoL) of 18 to 25-year-old Iranians who sought orthodontic treatment. MATERIALS AND METHODS: A total of 126 patients between 18 and 25 years attending some private orthodontic clinics answered the oral health impact profile-14 (OHIP-14) and a demographic questionnaire. Two calibrated orthodontists recorded the Index of Orthodontic Treatment Need-Dental Health Component (IOTN-DHC) determining the severity of malocclusion (Kappa = 0.8). The IOTN-Aesthetic Component (IOTN-AC) was reported by patients for assessing the perception of their esthetic severity of malocclusion. Logistic regression analysis was used. Level of significance was set at α = 0.05. RESULTS: The mean score of OHIP-14 was 20.87 ± 8.6. The frequency of patients with no/slight, borderline, and definite need for orthodontic treatment was determined as 13.4%, 23.8%, and 62.7%, respectively, by IOTN-DHC. There were significant correlations between borderline or definite need treatment and OHIP-14 overall score (P < 0.05). Patients with borderline and definite need for orthodontic treatment had 5 and 21 times lower QoL, respectively, than those with a slight need for orthodontic treatment. Based on IOTN-AC, 50.8% of the patients mentioned slight or no need based on IOTN-AC. No significant association was noted between IOTN-AC and OHIP-14 overall scores. CONCLUSIONS: The results showed negative impact of malocclusion severity on the QoL. This study highlighted the importance of individual assessment of orthodontic patients.

Interleukin-2, -16, and -17 gene polymorphisms in Iranian patients with chronic periodontitis.

AIM: Chronic periodontitis (CP) is a multifactorial disease and the most common type of periodontitis mainly caused by microbial plaque. CP can be brought on by, and progresses with, insufficient oral hygiene, and environmental and genetic susceptibilities. The aim of the present study was to investigate the association between interleukin (IL)-2 (T-330G), IL-16 (T-295C), and IL-17 (A-7383G) gene polymorphisms and the susceptibility to CP in an Iranian population. METHODS: Ninety-nine cases diagnosed with CP and 75 matched healthy controls engaged in the present study. 3 cc peripheral blood samples were obtained for DNA isolation. Genotype analysis was performed using restriction fragment length polymorphism polymerase chain reaction. Genotype distribution and allele frequencies within groups were compared using χ2 -test, and logistic regression analysis was used to recognize the independent relation between the disease and the absence or presence of alleles. RESULTS: There was no polymorphism in IL-2 (T-330G) among our patients, and the TT genotype was present in both study groups. Moreover, none of the studied genotypes and alleles of IL-16 (T-295C) and IL-17 (A-7383G) was significantly associated with CP. CONCLUSION: The present study demonstrated no association between IL-2 (T-330G), IL-16 (T-295C), and IL-17 (A-7383G) genotypes and CP in an Iranian population.

The Impact of Plasma Treatment of Cercon® Zirconia Ceramics on Adhesion to Resin Composite Cements and Surface Properties.

Introduction: In recent years, the use of ceramic base zirconia is considered in dentistry for all ceramic restorations because of its chemical stability, biocompatibility, and good compressive as well as flexural strength. However, due to its chemical stability, there is a challenge with dental bonding. Several studies have been done to improve zirconia bonding but they are not reliable. The purpose of this research is to study the effect of plasma treatment on bonding strength of zirconia. Methods: In this in vitro study, 180 zirconia discs' (thickness was 0.85-0.9 mm) surfaces were processed with plasma of oxygen, argon, air and oxygen-argon combination with 90-10 and 80-20 ratio (n=30 for each group) after being polished by sandblast. Surface modifications were assessed by measuring the contact angle, surface roughness, and topographical evaluations. Cylindrical Panavia f2 resin-cement and Diafill were used for microshear strength bond measurements. The data analysis was performed by SPSS 20.0 software and one-way analysis of variance (ANOVA) and Tukey test as the post hoc. Results: Plasma treatment in all groups significantly reduces contact angle compare with control (P=0.001). Topographic evaluations revealed coarseness promotion occurred in all plasma treated groups which was significant when compared to control (P<0.05), except argon plasma treated group that significantly decreased surface roughness (P<0.05). In all treated groups, microshear bond strength increased, except oxygen treated plasma group which decreased this strength. Air and argon-oxygen combination (both groups) significantly increased microshear bond strength (P<0.05). Conclusion: According to this research, plasmatic processing with dielectric barrier method in atmospheric pressure can increase zirconia bonding strength.