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This retrospective study was aimed to compare the clinical and radiographic outcomes of implants with the same body design but different collar surface (laser-microtextured vs. not laser-microtextured) after functional loading. Forty-three patients (29 females, 14 males) with 139 implants (60 laser-microtextured and 79 without laser microtexturing) were included in this study. Patients were consecutively included, and the data were collected during their implant maintenance visit. Clinical and radiographic parameters including probing depth (PD), bleeding on probing (BoP), and marginal bone loss (MBL) were recorded. In addition, the implant success index (ISI) score was determined. Statistical analysis was performed using the Mann–Whitney U test, the Kruskal–Wallis rank test, or the Pearson χ2 test, along with binary logistic regression (p

Background Improvement in implant design has made implant dentistry a challenging treatment modality worldwide. Objectives This study aimed to investigate the efficacy of a xenogeneic collagen matrix in managing 3-4-millimeter gaps in flapless immediate implant placement. Material and methods Twenty-two patients received 39 immediate implants via the flapless approach. Patients with intact bony walls, buccal bone thickness ≥2 mm and a jumping distance of 3-4 mm were included in this study. The gap between the implant and the socket walls was filled with a xenogeneic collagen matrix (Collacone®). The final clinical and radiographic evaluations were performed at least 24 months following functional loading. Results There was no early or late failure, and the implants showed a 100% survival rate. The mean mesial (0.28 ±0.39 mm) and distal (0.28 ±0.39 mm) marginal bone loss (MBL) at the site of incisors was not significantly different from the values at the site of premolars and molars (0.30 ±0.42 mm and 0.34 ±0.48 mm, respectively). The evaluation of the implant success index (ISI) score revealed no difference between the mandible and the maxilla (p = 0.700), or incisors compared with premolars and molars (p = 0.420). The only significant difference was in terms of distal MBL, which was higher in the maxilla (0.39 ±0.49 mm) than in the mandible (0.12 ±0.23 mm) (p = 0.040). Conclusions Within the limitations of this study, it seems that the application of a xenogeneic collagen matrix to manage 3-4-millimeter gaps in carefully selected cases may bring promising outcomes.

Peri-implantitis is a biofilm-induced pathological condition, and different approaches have been proposed to manage this condition. This study introduces a surgical technique in accordance with the concept of guided bone regeneration for implants with extensive peri-implant defects. This pilot study was conducted on 7 patients with 11 implants (4 females and 3 males; 32 to 61 years). In this technique, we used a titanium mesh, a combination of autogenous bone, allogenic graft material, and acellular dermal matrix to reconstruct the peri-implant defects. All implants were placed submerged, and the second-stage surgery was conducted after 8 months. Soft tissue augmentation and vestibuloplasty were performed in the second-stage surgery, if required. The mean function time of implants was 60.5 ± 29.4 months. The mean baseline probing pocket depth was 5.7 ± 1.4 mm, and soft tissue recession was observed at two sites (18%). The mean recession and keratinized tissue width (KTW) values were 0.4 ± 0.8 mm and 3 ± 1.6 mm, respectively. The mean marginal bone loss and bone gain were 4.4 ± 1.2 mm and 2.9 ± 0.9 mm, respectively, which showed a significant improvement. Our preliminary evaluations showed favorable results in terms of radiographic defect fill and soft tissue condition. It appears that this technique may lead to promising outcomes in cautiously selected patients seeking to retain their failing implants. However, long-term results following functional loading are required before recommending this technique for daily practice.

This study retrospectively evaluated the effect of soft tissue condition on peri-implant health. Clinical variables (Plaque Index, keratinized tissue width, gingival biotype, and vestibular depth) were recorded. Probing depth, soft tissue recession, bleeding on probing, and radiographic marginal bone loss were assessed in relation to independent variables. Statistical analysis was performed using Mann-Whitney U test or Kruskal-Wallis rank test and a logistic regression model at the implant level. A total of 139 implants in 43 patients were assessed. Bleeding on probing was recorded at 54.7% sites, which was significantly related to the biofilm accumulation. Gender, history of periodontal disease, patient adherence to recall visits, and the presence of plaque were associated with higher peri-implant probing-depth values. The maximum soft tissue recession was recorded at sites with a thin biotype and shallow vestibular depth (P = .0). The logistic regression analysis revealed that plaque (P = .002) and vestibular depth (P = .043) were significantly associated with peri-implantitis. Within the study limitations, patients with high plaque accumulation and shallow vestibular depth are more prone to peri-implant disease.

Background. This study aimed to assess the association of haptoglobin (HP) and natural resistance-associated macrophage protein 1 (NRAMP1) alleles with the presence of heme-consuming periodontal pathogens in a group of Iranian patients with chronic periodontitis and peri-implantitis. Methods. This cross-sectional study evaluated 69 eligible chronic periodontitis and peri-implantitis patients selected from Shahid Beheshti Dental School. The periodontally diseased individuals had at least three teeth with clinical attachment loss of ≥3 mm and a probing pocket depth (PPD) of ≥3 mm in at least two quadrants. Peri-implant PPD of at least one site was ≥5 mm with or without suppuration and bleeding on probing. A plaque index of >20% and a radiographic crestal bone loss was present in at least one site around the implant. The paper point method was used for sampling from the deepest periodontal/peri-implant pocket of each tooth or implant for the DNA checkerboard hybridization technique. Statistical analyses were performed with PASW Statistics 18.0. The variables were presented as absolute and relative frequencies (%). Results. An Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) score of 1–2 was 5.8 times more frequent in HP 2, rs1723540 G, and rs2276631 G alleles. A Porphyromonas gingivalis (P. gingivalis) score of 1–2 was 4.8 times more common in the subjects carrying HP 2, rs1723540 G, and rs2276631 G alleles compared with HP 1, rs1723540 A, and rs2276631 A alleles. Conclusion. Within the limitations of this study, it seems that there was a relationship between HP and NRAMP1 allele frequencies and the presence of heme-consuming periodontal pathogens in the Iranian patients with chronic periodontitis and peri-implantitis evaluated in the present study.

Peri-implantitis (PI) is a multifactorial condition caused by the interactions of pathogens and the host immune response. Previous studies have demonstrated a relationship between PI and specific gene polymorphisms, particularly cytokine genes involved in the pathogenesis of PI. This study aimed to evaluate the frequency of single nucleotide polymorphisms (SNPs) of interleukin-10 (IL-10), interleukin 1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) genes in PI patients and healthy controls. A total of 50 patients with PI and 89 periodontally healthy controls were recruited for this study. Venous blood samples (5 cc) were collected, and DNA was extracted. After DNA purification, the relevant gene segments were amplified by polymerase chain reaction (PCR). Restriction fragment length polymorphism (RFLP) and electrophoresis were performed to assess the polymorphisms of the related genes. The analysis revealed that allele and genotype frequencies of IL-10 ─ 819 C/T, IL-10 ─ 592 C/A, and IL-1ß + 3954 C/T significantly differed between PI patients and healthy controls. The analysis revealed no significant association between TNF-α ─ 857 G/A and TNF-α ─ 308 G/A polymorphisms and PI. Our results indicated that specific gene polymorphisms of IL-10 ─ 819 C/T, IL-10 ─ 592 C/A, and IL-1ß + 3954 C/T may play a role in the pathogenesis of PI, and increase its risk of occurrence.

Background. Visfatin (pre-B-cell colony-enhancing factor) is a salivary biomarker secreted from a variety of cells and is thought to have some proinflammatory and immune-modulating effects. This study compared salivary concentrations of visfatin in patients with chronic periodontitis and periimplantitis and healthy individuals. Methods. In this cross-sectional and descriptive trial, patients were selected on the basis of inclusion and exclusion cri-teria. The whole saliva samples were collected; then according to the measured clinical parameters the patients were cate-gorized to peri-, chronic periodontitis and periodontally healthy individuals. The concentrations of visfatin were evaluated using a standard ELISA kit. The salivary concentrations of visfatin were statistically analyzed using Kruskal-Wallis test. A probability value of less than 0.05 was considered significant. Results. A total of 40 participants (21 females and 19 males) were enrolled in this study. The mean salivary visfatin con-centrations in the periodontally healthy individuals, periimplantitis patients and chronic periodontitis patients were 23.97 ng/mL, 12.83 ng/mL and 11.95 ng/mL, respectively. However; visfatin levels were higher in healthy individuals compared to other groups No significant differences were found in salivary visfatin concentrations between the three groups. Conclusion. Under the limitations of this study, no significant relationships were found regarding salivary concentrations of visfatin among periimplantitis and chronic periodontitis patients as compared to healthy individuals; however, more studies are required in this regard. Key words: Visfatin, saliva, periimplantitis, chronic periodontitis.

Background. Despite successful results of implant therapy, complications occasionally occur in challenging situations.Apart from academic courses for implantology, dental associations also offer training courses for general practitioners.We sought to assess dentists' attitude towards peri-implant diseases. Methods. The subjects in thisquestionnaire-based cross-sectional study consisted of dentists participating in the annual congress of the Iranian Dental Association in 2013, whose knowledge and attitudes towards peri-implant diseases were assessed using a five-section questionnaire (implant therapy training, peri-implant soft tissue assessment, peri-implant diseases and treatment planning for peri-implant diseases). Data were analyzedwith SPSS 22, using descriptive and analytical methods. Results. The results showed that due to extensive placement of implants and high prevalence of complications, academic and organized training courses are essential. Conclusion. The results showed that due to extensive placement of implants and high prevalence of complications, academic and organized training courses are essential.

Background. This study aimed to assess Aggregatibacter actinomycetemcomitans (Aa) and Prevotella intermedia (PI) counts in gingival crevicular fluid (GCF) around healthy implants, diseased implants and sound teeth. Methods. Eight patients (four males and four females), who had healthy implants, implants with peri-implantitis and sound teeth, were selected. Samples (GCF) were analyzed using real-time polymerase chain reaction (RT-PCR). The above-mentioned bacteria were detected and counted. Data analysis in RT-PCR was carried out based on the standard curve using Prism software to compare Pi and Aa counts between the three areas (GCF around sound teeth, healthy implants and implants with peri-implantitis). Results. Pi counts were significantly higher in GCF around implants with peri-implantitis (8 implants) than around healthy implants (8 implants) (P

COVID-19 has imposed tremendous burden on the healthcare systems and healthcare professionals worldwide. As periodontitis and peri-implantitis are chronic diseases, regular recall visits play a critical role in management of these conditions; however, the current situation may stop patients from attending their regular maintenance. Therefore, it may be necessary to reconsider and revise the treatment protocols.

This study was conducted on 87 patients with chronic periodontitis (CP), 50 patients with peri-implantitis and 90 periodontally healthy individuals referring to the Department of Periodontics for evaluating the association between Fc gamma-receptor genes polymorphisms with CP and peri-implantitis. After obtaining consent, venous blood samples (5cc) were obtained from patients and DNA was extracted using Miller's salting-out method. Polymerase chain reaction (PCR)-restriction fragment length polymorphism and tetra-primer amplification refractory mutation system-PCR methods were used to assess the polymorphisms of FcγRs IIa, IIIa, and IIIb genes. Analyzing showed a significant association between specific genotypes with increasing CP and peri-implantitis risks in codominant and dominant models. For FcγR IIIa, analyzing revealed a significant association between specific genotypes with increasing CP and peri-implantitis risks in codominant, dominant, and recessive models. For FcγR IIIb, we also detected a significant association between specific genotypes with increasing CP and peri-implantitis risks in codominant, dominant, and recessive models ( P

Periodontitis is an infectious disease of the tooth-supporting tissues. Specific periodontal pathogens trigger inflammatory responses and result in progressive bone loss, which eventually leads to exfoliation of teeth. Periimplantitis is the destructive inflammatory process affecting the soft and hard tissues surrounding dental implants. The periodontal pathogens found around failing implants are very similar to those associated with various forms of periodontal diseases. Genetic susceptibility has been known to be an important risk factor for periodontitis and periimplantitis and there have been numerous studies evaluating this in different populations. Many gene polymorphisms may influence individual susceptibility to periodontitis and peri-implantitis. We conducted a review of the literature for gene polymorphisms associated with periodontitis and peri-implantitis susceptibility in the Iranian population. A comprehensive search of the literature on human studies in English, published from January 2004 to February 2015 in PubMed database and Google scholar was performed using the key words "periodontitis," "peri-implantitis," "gene polymorphisms," and "Iranian population." Sixty-six studies were identified; 33 articles were excluded based on review of titles and abstracts. Thirty articles were eligible and had the full text evaluated. Further studies are needed to get more inclusive perception of the influence of gene polymorphisms in periodontitis and peri-implantitis.

Objective RANK/OPG/RANKL pathway plays a significant role in osteoclastogenesis, osteoclast activation, and regulation of bone resorption. The aim of this study was to investigate the association of RANKL gene polymorphisms (rs9533156 and rs2277438) with chronic periodontitis and peri-implantitis in an Iranian population. Design 77 patients with chronic periodontitis, 40 patients with peri-implantitis and 89 periodontally healthy patients were enrolled in this study. 5cc of blood was obtained from the cephalic vein of subjects arms and transferred into tubes containing EDTA. Genomic DNA was extracted using Miller's Salting Out technique. The DNA was transferred into 96 division plates, transported to Kbioscience Institute in United Kingdom and analyzed using the Kbioscience Competitive Allele Specific PCR (KASP) technique. Differences in the frequencies of genotypes and alleles in the disease and control groups were analyzed using Chi-square and Fisher's exact statistical tests. Results Comparison of frequency of alleles in SNP rs9533156 of RANKL gene between the chronic periodontitis group with the control and peri-implantitis groups revealed statistically significant differences ( P = 0.024 and P = 0.027, respectively). Comparison of genotype expression of SNP rs9533156 on RANKL gene between the peri-implantitis group with chronic periodontitis and control groups revealed statistically significant differences ( P = 0.001); the prevalence of CT genotype was significantly higher amongst the chronic periodontitis group. Regarding SNP rs2277438 of RANKL gene, comparison of prevalence of genotypes and frequency of alleles did not reveal any significant differences ( P = 0.641/ P = 0.537, respectively). Conclusions The results of this study indicate that CT genotype of rs9533156 RANKL gene polymorphism was significantly associated with peri-implantitis, and may be considered as a genetic determinant for peri-implantitis.

AIM: MicroRNAs (MiRs) are small noncoding RNAs that are involved in protein translation, osteoclastogenesis, and immunoregulation. Peri-implantitis and chronic periodontitis are multifactorial diseases. They are the consequence of complex interactions among host response, genetics, and environment. In the present study, we aimed to investigate the possible association between MiR146a/MiR499 gene polymorphisms and periodontitis/peri-implantitis as a first report in oral implantology. METHODS: From 197 individuals referred to Periodontology Department of Shahid Beheshti Dental School, three groups were enrolled in the assessment: 75 patients in the chronic periodontitis (CP) group, 38 patients in the peri-implantitis (PI) group, and 84 healthy subjects. DNA was extracted from fresh blood samples from the arm veins of participants and transferred to KBiosience Institute (Hoddesdon, United Kingdom) for genotyping. Chi-squared and Kruskal-Wallis tests were performed using SPSS software v.19 for statistical analyses. P-value < 0.05 was considered significant. RESULTS: The genotype frequencies in MiR 146a and MiR 499 were significantly different among the three groups. CONCLUSIONS: MiR146a (rs2910146) and MiR499 (rs3746444) gene polymorphisms may be genetic determinants for increased risk of chronic periodontitis and peri-implantitis in Iranians. More studies with larger sample sizes in different populations are necessary for determining the effect of these SNPs.

J Korean Assoc Oral Maxillofac Surg 2014;40:220-224) Objectives: This study aimed to assess and compare the levels of interleukin-1beta (IL-1β ) and interleukin-6 (IL-6) in the crevicular fluid around healthy implants, implants with peri-implantitis, and healthy teeth. Materials and Methods: This study evaluated 16 dental implants in 8 patients (4 males and 4 females). These patients had at least one healthy im- plant and one implant with peri-implantitis next to healthy teeth. The crevicular fluid was collected using absorbent cones and transferred to the labora - tory. Specimens were evaluated by ELISA for interleukin levels. Data were analyzed using repeated measures ANOVA and Bonferroni tests (P

UNLABELLED: This study sought to determine TANK (rs1921310, rs3820998) gene polymorphism in patients suffering from chronic periodontitis and peri-implantitis among an Iranian population. MATERIALS AND METHODS: In this cross-sectional study, 77 chronic periodontitis and 40 peri-implantitis patients, along with 89 periodontally healthy subjects, were evaluated. A 5 cc venous blood sample was obtained from subjects. DNA was extracted using Miller's salting-out method and polymorphisms were determined by the use of KBioscience's Competitive Allele-Specific PCR (CASP) genotyping system. Data were analyzed using SPSS version 11.5 software. Differences in allele and genotype frequencies among patients and controls were evaluated with Kruskal-Wallis test. P

AIM In the present study, we sought to assess the correlation of IKKi gene polymorphisms (rs1539243 and rs12728136) with chronic periodontitis and peri-implantitis in an Iranian population for the first time in dentistry. MATERIALS AND METHODS This cross-sectional study was conducted on 75 patients with chronic periodontitis, 38 patients with peri-implantitis, and 84 periodontally healthy subjects. Blood samples were taken from all subjects (5 cc venous) and transferred into Falcon tubes containing EDTA. Extracted DNA samples were evaluated with a spectrophotometer (75 ng), transferred into a 96-well plate, and sent to KBioscience Institute in the United Kingdom for analysis. Assessment of IKKi gene polymorphisms was performed at the KBioscience Institute. Data were analyzed using SPSS v19 software. Differences in genotype frequencies and allele among patients and controls were evaluated using the chi-squared test (P

Periodontal disease (PD) and peri-implantitis (PI) are characterized by an immune response leading to destructive inflammation. The prominent impact of genetic factors on periodontitis has been previously evaluated and IL-17 has found to play a critical role in this process. This cytokine has a controversial behavior. This study aimed at finding out whether the polymorphism of this cytokine plays a significant role in chronic periodontitis (CP) and PI or it is just a pro-inflammatory regulatory cytokine. Fresh human blood samples were obtained and three main genotypes were traced carefully. The samples were transferred into 96-well plates and sent to KBioscience Institute in the United Kingdom for genotyping the polymorphism using Competitive Allele Specific PCR (KASP) technique. SPSS version19 software and chi-square and Kruskal-Wallis tests were used for statistical differences considering p-value less than 0.05. A significant difference was detected between the three groups in terms of specific SNP studied in this experiment (P = 0.00). The CC genotype of IL17 polymorphism (rs10484879) may contribute to the pathogenesis of peri-implantitis and periodontitis. The association of IL-17 polymorphism with PI and CP is a promising finding that may help in future similar studies on other ethnicities and larger study populations.

Receptor activator for nuclear factor kappa B ligand (RANKL)/RANK/OPG pathway plays a redundant role in osteoclastogenesis, osteoclast activation and regulation of bone resorption. Recently, single nucleotide polymorphisms (SNP) have been reported as a co-factor in pathogenesis of inflammatory diseases. The aim of this study was to investigate the relationship between osteoprotegerin (OPG) gene polymorphisms and chronic periodontitis and peri-implantitis in an Iranian population.77 patients with chronic periodontitis (CP), 40 patients with peri-implantitis (PI) and 89 periodontally healthy subjects were enrolled in this study. A total of 5 ml of blood was obtained from the arm vein of participants. DNA was extracted based on the salting out method. Two functional SNPs (T950C and G1181C) were analysed by using polymerase chain reaction and restriction fragment length polymorphism (PCR_RFLP). The prevalence differences in three batches were evaluated by chi-square test.An evaluation of the T950C genotype found that there was no statistical difference between groups. A comparison of the G1181C genotype distribution between peri-implantitis and chronic periodontitis groups, and between peri-implantitis and normal groups found that the frequency of the CC genotype was significantly higher in patients with peri-implantitis (P = 0.005).Our results indicate that a SNP at G1181C is associated with the presence of PI.

BACKGROUND Chronic periodontitis (CP) and peri-implantitis (PI) are inflammatory diseases that affect supporting tissues of teeth or implants. The involvement of hyperpolarization-activated cyclic nucleotide-gated 2 (HCN2) in neuronal excitability, hyperalgesia, allodynia, spontaneous pain, synaptic plasticity, and rebound activity was previously determined. Recently, scientists found that HCN2 plays an important role in chronic inflammatory pain. This study aimed to evaluate the relationship between gene polymorphisms of HCN2 and CP/PI. METHODS A total of 74 patients with CP, 37 patients with PI, and 80 healthy controls presenting to the Periodontology Department of Shahid Beheshti University of Medical Sciences were enrolled. DNA was extracted from fresh blood samples of the arm vein of participants and transferred to KBioscience Institute (UK) for genotyping. χ2-test was performed with SPSS software v.19 for statistical analyses. A p value

BACKGROUND Peri-implantitis (PI) and chronic periodontitis (CP) are multifactorial diseases of implant/tooth supporting tissue that are caused by bacterial infection and increased host immune response. T-cell proliferation plays a pivotal role in the orchestration of host response to bacterial infection. BRAF is a positive regulator of T-cell proliferation. The aim of this study was to evaluate for the first time the role of a functional single nucleotide polymorphism (SNP) of the BRAF gene in association to PI and CP. METHODS A total of 194 individuals referred to the Periodontology Department of Shahid Beheshti Dental School, Tehran, Iran, were divided into three groups: 74 patients in the CP group (39 men and 35 women, with mean age of 48.3 years), 38 patients in the PI group (20 men and 18 women, with mean age of 50.2 years), and 82 patients in the healthy periodontium group (39 men and 43 women, with mean age of 45.4 years). DNA was extracted from fresh blood samples collected from the arm vein of participants and was transferred to KBiosience institute (United Kingdom) for genotyping. χ2 and Kruskal-Wallis tests were conducted using SPSS software v. 19 for statistical analysis (p

Aim The haptoglobin–hemoglobin (Hp–Hb) complex plays a significant role in regulating immune responses and acts as a bacteriostatic agent. Haptoglobin polymorphisms result in different Hb binding affinities. This study sought to assess whether Hp 2-2 could be a genetic determinant for increasing the risk of peri-implantitis and chronic periodontitis. Methods Of the Iranian subjects referred to the Department of Periodontics, Shahid Beheshti University, Tehran, 203 were entered into the study, including 117 patients and 86 periodontally healthy individuals. Polymerase chain reaction (PCR) was performed for genotyping. Data were analyzed by Kruskal–Wallis test using the SPSS statistics software package. Results The prevalence of Hp 2-2, 2-1, and 1-1 did not differ significantly between patients and healthy subjects (P > 0.05). The highest frequencies of Hp 1-1, 2-1, and 2-2 genotypes were seen in the control (7%), peri-implantitis (51%) and periodontitis (64%) groups, respectively. Conclusions Haptoglobin polymorphisms may not play a role in development of peri-implantitis or chronic periodontitis among Iranians but we strongly suggest researchers to evaluate this polymorphism in further studies on larger sample sizes, different populations, and other types of periodontitis.

Objectives: The present study was conducted to determine the reproducibility of peri-implant tissue assessment using the new implant success index (ISI) in comparison with the Misch classification. Materials and Methods: In this descriptive study, 22 cases of peri-implant soft tissue with different conditions were selected, and color slides were prepared from them. The slides were shown to periodontists, maxillofacial surgeons, prosthodontists and general dentists, and these professionals were asked to score the images according to the Misch classification and ISI. The intra- and inter-observer reproducibility scores of the viewers were assessed and reported using kappa and weighted kappa (WK) tests. Results: Inter-observer reproducibility of the ISI technique between the prosthodontists-periodontists (WK=0.85), prosthodontists-maxillofacial surgeons (WK=0.86) and periodontists-maxillofacial surgeons (WK=0.9) was better than that between general dentists and other specialists. In the two groups of general dentists and maxillofacial surgeons, ISI was more reproducible than the Misch classification system (WK=0.99 versus WK noncalculable, WK=1 and WK=0.86). The intra-observer reproducibility of both methods was equally excellent among periodontists (WK=1). For prosthodontists, the WK was not calculable via any of the methods. Conclusion: The intra-observer reproducibility of both the ISI and Misch classification techniques depends on the specialty and expertise of the clinician. Although ISI has more classes, it also has higher reproducibility than simpler classifications due to its ability to provide more detail.

Purpose: Peri-implantitis and periodontitis are inflammatory and infectious diseases of im- plant and tooth-supporting tissues. Recently, the role of gene polymorphisms of immune re- sponse components in the relevant pathogenesis has been investigated. The present study was the first to evaluate the relationship between two known single nucleotide polymorphisms (SNPs) of the receptor activator of nuclear factor kappa-β (RANK) gene (rs3018362 and rs35211496) in chronic periodontitis and peri-implantitis patients in an Iranian population. Methods: Eighty-one periodontally healthy patients, 38 patients with peri-implantitis, and 74 patients with chronic periodontitis were enrolled in this study. DNA was extracted from blood arm vein samples by using Miller's salting out technique according to the manufac- turer's instructions given in the extraction kit. The concentration of DNA samples was mea- sured using a spectrophotometer. The genetic polymorphisms of the RANK gene were eval- uated using a competitive allele specific polymerase chain reaction (KBioscience allele spe- cific PCR) technique. Differences in the frequencies of genotypes and alleles in the diseased and healthy groups were analyzed using chi-squared statistical tests (P < 0.05). Results: Analysis of rs35211496 revealed statistically significant differences in the expres- sion of the TT, TC, and CC genotypes among the three groups (P = 0.00). No statistically sig- nificant difference was detected in this respect between the control group and the chronic periodontitis group. The expression of the GG, GA, and AA genotypes and allele frequencies (rs3018362) showed no statistically significant difference among the three groups (P = 0.21). Conclusions: The results of this study indicate that the CC genotype of the rs35211496 RANK gene polymorphism was significantly associated with peri-implantitis and may be considered a genetic determinant for peri-implantitis, but this needs to be confirmed by further studies in other populations.

Chronic periodontitis (CP) and peri-implantitis (PI) are multifactorial diseases of tooth and implant supporting apparatus. Bacterial invasion and consequent host immune response seem to play a role in relevant pathogenesis. The structural differences between tooth and implant pose preferential biofilm colonization. This study was aimed to compare the prevalence of bacteria in CP and PI. Clinical and radiographic examination performed over 69 individuals referred to Shahid Beheshti Dental School (Tehran, Iran) and four groups categorized: CP (n=22), HP (n=21), PI (n=13) and HI (n=13). The mean age was 45.6 years, 55% of participants were female and 45% were male. Bacterial samples were collected by paper point method and transferred to Institute of Odontology, University of Gothenburg (Gothenburg, Sweden) for checkerboard DNA-DNA hybridization. Kruskal-Wallis and Mann-Whitney U tests were used to compare distribution of bacteria in four groups. Significant differences were observed for T. forsythia, P. intermedia, C. rectus, P. endodontic, P. gingivalis, T. denticola and P. tannerae (P

Introduction There are numerous studies supporting the high success rate of dental implants used for reconstruction of missing teeth. However, complications like mucositis and peri-implantitis are increasingly reported. Placement of dental implants in partially edentulous patients is associated with the risk of peri-implant diseases, especially when an old or a new inflammatory lesion is present adjacent to the implant site. Although no consensus has been reached on the difference in prevalence of peri-implant mucositis and peri-implantitis between fully and partially edentulous patients, available data clearly show that the combination of periodontal lesion and peri-implantitis is a possible risk factor for further complications. Several classification systems have been suggested for determination of the severity of disease around dental implants. However, no classification has been proposed for combined biological complications around teeth and implants. This study reviews the possible pathologic communication routes between natural dentition and the implants installed adjacent to them. Furthermore, we introduce a new classification system for the peri-implant disease in association with natural teeth called “PIST”. This system was designed based on the origin of the defects in order to clarify the different pathological situations which can be detected around dental implant. Using this classification system can help improve diagnosis, comparison and subsequent selection of the best treatment option.

Gene polymorphism of cytokines influencing their function has been known as a contributing factor in the pathogenesis of inflammatory diseases of the tooth and implant supporting tissues. The aim of this study was to investigate the association of IL-17R gene polymorphism (rs879576) with chronic periodontitis and periimplantitis in an Iranian population. 73 patients with chronic periodontitis, 37 patients with periimplantitis and 83 periodontally healthy patients were enrolled in this study. 5cc blood was obtained from each subject's arm vein and transferred to tubes containing EDTA. Genomic DNA was extracted using Miller's Salting Out technique. The DNA was transferred into 96 division plates, transported to Kbioscience Institute in United Kingdom and analyzed using the Kbioscience Competitive Allele Specific PCR (KASP) technique. Chi-square and Kruskal Wallis tests were used to analyze differences in the expression of genotypes and frequency of alleles in disease and control groups (P-Value less than 0.05 was considered statistically significant). There were no significant differences between periodontitis, periimplantitis with AA, GG, GA genotype of IL-17R gene (P=0.8239). Also comparison of frequency of alleles in SNP rs879576 of IL-17R gene between the chronic periodontitis group and periimplantitis group did not revealed statistically significant differences (P=0.8239). The enigma of IL-17 and its polymorphism-role in periodontitis and periimplantitis is yet to be investigated more carefully throughout further research but this article demonstrates that polymorphism of IL-17R plays no significant role in incidence of chronic periodontitis and Periimplantitis.