Seismic response prediction of FRC rectangular columns using intelligent fuzzy-based hybrid metaheuristic techniques.

This research study focused on the dynamic response and mechanical performance of fiber-reinforced concrete columns using hybrid numerical algorithms. Whereas test data has non-linearity, an artificial intelligence (AI) algorithm has been incorporated with different metaheuristic algorithms. About 317 datasets have been applied from the real test results to detect the promising factor of strength subjected to the seismic loads. Adaptive neuro-fuzzy inference system (ANFIS) was carried out as an AI beside the combination of particle swarm optimization (PSO) and genetic algorithm (GA). Extreme Machine Learning (ELM) was also performed in order to approve the obtained results. According to the findings, it is demonstrated that ANFIS-PSO predicts the lateral load with promising evaluation indexes [R2 (test) = 0.86, R2 (train) = 0.90]. Mechanical performance prediction was also carried out in this study, and the results showed that ELM predicts the compressive strength with promising evaluation indexes [R2 (test) = 0.66, R2 (train) = 0.86]. Finally, both ANFIS-GA and ANFIS-PSO techniques illustrated a reliable performance for prediction, which encourage scholars to replace costly and time-consuming experimental tests with predicting utilities.

Association between Marginal Bone Loss and Bone Quality at Dental Implant Sites Based on Evidence from Cone Beam Computed Tomography and Periapical Radiographs.

OBJECTIVE: The aim of this study was to assess bone quality in patient's preoperative cone beam computed tomography (CBCT) and their relation with marginal bone loss at implant placement sites over follow-up periods. MATERIALS AND METHODS: In this retrospective cross-sectional study, 100 implants were evaluated. The implants had been placed in the maxillary and mandibular edentulous areas. Bone quality at implant placement sites was measured on preoperative CBCTs and then classified by two observers according to Lekholm and Zarb classification. Marginal bone height was then measured on periapical radiographs obtained at baseline and then 6, 12, 18, 24, and 30 months' follow-up periods from a reference point (implant shoulder) to the bone-implant interface. The relation between bone quality and bone loss was assessed. ANOVA was used to compare mean difference among groups and Pearson correlation coefficient to assess the correlation between observers. All statistical analyses were performed at 0.05 significance level using Stata 11 software (StataCorp, College Station, TX, USA). RESULTS: Of 100 implants, 48 were placed in the maxilla and 52 in the mandible. There was no significant difference between bone quality and the mean bone loss at follow-up periods. Using Pearson's correlation coefficient, it was shown that with an increase in bone quality, marginal bone loss was decreased at follow-up periods. CONCLUSIONS: The results confirmed that during the follow-up periods, less bone loss was observed in implant areas with higher bone quality and CBCT is a reliable tool for assessing bone quality at implant placement sites and estimation of subsequent treatment prognosis.

Comparing the effect of preparation of the implant sites with piezosurgery and conventional drilling on the stability of implants at 5-months follow-up.

The objective of this study was to compare the effects of preparing for implant site osteotomy with conventional drilling or piezosurgery on the stability of oral implants after a 5 month follow-up period. Thirty patients participated in this randomized clinical trial and received two implants in posterior mandible in bone of the same quality. All surgical procedures were performed by the same surgeon. Implant stability amounts were measured by resonance frequency analysis using the Osstell Mentor device and are reported in the format of implant stability quotient (ISQ) values at baseline and 90 and 150 days after surgery. All implants were well osseointegrated. Differences in ISQ levels were statistically significant in the piezosurgery group at all time intervals, whereas those in the conventional drill group were not significant as analyzed by analysis of variance. The significance of differences between the two groups in each time interval was assessed with Student's t test. In the second interval (90 days), there were statistically significant differences in ISQ levels between the two groups at the buccal, lingual side of implants and mean of two measurements, but at baseline and 150 days, there were no significant differences between these techniques. The early increase of ISQ values in piezoelectric sites shows that piezosurgery is a less traumatic bone osteotomy method with a shorter inflammatory phase and little resorption compared with sites prepared by conventional drilling. ISQ values of up to 60-65 at the time of insertion of the implant predict a good prognosis for immediate implant loading. In this study, the ISQ values were almost always higher than this, offering the safe condition for immediate or early loading protocols after the piezoelectric method of implant site osteotomy. These results may increase predictability of immediate-loading procedure in oral implantology.

Effect of field-of-view size on gray values derived from cone-beam computed tomography compared with the Hounsfield unit values from multidetector computed tomography scans.

PURPOSE: This study aimed to evaluate the effect of field-of-view (FOV) size on the gray values derived from conebeam computed tomography (CBCT) compared with the Hounsfield unit values from multidetector computed tomography (MDCT) scans as the gold standard. MATERIALS AND METHODS: A radiographic phantom was designed with 4 acrylic cylinders. One cylinder was filled with distilled water, and the other 3 were filled with 3 types of bone substitute: namely, Nanobone, Cenobone, and Cerabone. The phantom was scanned with 2 CBCT systems using 2 different FOV sizes, and 1 MDCT system was used as the gold standard. The mean gray values (MGVs) of each cylinder were calculated in each imaging protocol. RESULTS: In both CBCT systems, significant differences were noted in the MGVs of all materials between the 2 FOV sizes (P<.05) except for Cerabone in the Cranex3D system. Significant differences were found in the MGVs of each material compared with the others in both FOV sizes for each CBCT system. No significant difference was seen between the Cranex3D CBCT system and the MDCT system in the MGVs of bone substitutes on images obtained with a small FOV. CONCLUSION: The size of the FOV significantly changed the MGVs of all bone substitutes, except for Cerabone in the Cranex3D system. Both CBCT systems had the ability to distinguish the 3 types of bone substitutes based on a comparison of their MGVs. The Cranex3D CBCT system used with a small FOV had a significant correlation with MDCT results.

Effect of Oral Bromelain on Wound Healing, Pain, and Bleeding at Donor Site Following Free Gingival Grafting: A Clinical Trial.

OBJECTIVES: Considering the optimal efficacy of bromelain for pain relief and wound healing, this study aimed to assess the effect of bromelain on wound healing, pain, and bleeding at the donor site following free gingival grafting (FGG). MATERIALS AND METHODS: This randomized, controlled double-blind clinical trial was performed on 26 patients with gingival recession. The patients were randomly divided into two groups of bromelain and placebo (n=13). Treatment was started on the day of surgery and was continued for 10 days. Pain, bleeding, and epithelialization at the donor site were the variables evaluated in this study using a questionnaire. The level of pain was determined using a visual analog scale (VAS) considering the number of analgesic tablets taken within 7 days postoperatively. Bleeding was determined according to the patient's report, and epithelization was assessed by applying 3% hydrogen peroxide (H2O2) to the donor site. The donor site epithelialization was assessed at 7 and 10 days after surgery. RESULTS: Bromelain caused a significant reduction in pain at the donor site (2.605±0.509) compared to the placebo (4.885±0.519; P<0.05). The number of donor sites with complete epithelialization was higher in the bromelain group compared to the placebo, but this difference was not statistically significant (P>0.05). The two groups were the same regarding postoperative bleeding (P>0.05). CONCLUSIONS: The results showed that oral bromelain (500 mg/day) can be effective in the reduction of pain at the donor site after FGG and may also enhance wound healing. Oral bromelain does not increase the risk of postoperative bleeding.

Comparison of Periodontal Ligament Stem Cells Isolated from the Periodontium of Healthy Teeth and Periodontitis-Affected Teeth.

OBJECTIVES: Stem cell (SC) therapy is a promising technique for tissue regeneration. This study aimed to compare the viability and proliferation ability of periodontal ligament stem cells (PDLSCs) isolated from the periodontium of healthy and periodontitis-affected teeth to obtain an autologous, easily accessible source of SCs for tissue regeneration in periodontitis patients. MATERIALS AND METHODS: The PDLSCs were isolated from the roots of clinically healthy premolars extracted for orthodontic purposes and periodontally involved teeth with hopeless prognosis (with and without phase I periodontal treatment). Cells were cultured and viability and proliferation ability of third passage cells in each group were evaluated using the methyl thiazol tetrazolium assay. The results were statistically analyzed using t-test. RESULTS: No SCs could be obtained from periodontitis-affected teeth without phase I periodontal treatment. The viability of cells was 0.86±0.13 OD/540 in healthy group and 0.4±0.25 OD/540 in periodontitis-affected group (P=0.035). The proliferation ability (population doubling time) of cells obtained from healthy teeth was 4.22±1.23 hours. This value was 2.3±0.35 hours for those obtained from periodontitis-affected teeth (P=0.02). CONCLUSIONS: Viability and proliferation ability of cells isolated from the periodontium of healthy teeth were significantly greater than those of cells isolated from the periodontitis-affected teeth.

Radiographic Evaluation of Bone-Level Implants with Wound Dehiscence between the First- and Second-Stage Surgeries.

BACKGROUND: One of the most common complications of implant surgery is wound dehiscence followed by exposure of the implant to the oral cavity. The aim of this study was to radiographically analyze crestal bone loss around bone-level implants with wound dehiscence between the first- and second-stage surgeries. METHODS: The records of 136 implants inserted during 2013-2014 were evaluated. Patients with no history of systemic disease, drug addiction, radiotherapy, or chemotherapy were selected. Forty-eight implants had cover screws with complete or partial exposure to the oral cavity after the suture removal and before the second surgery. Digital or normal radiographs were taken after the first and during the second surgery and the distance between the implant shoulder and proximal bone crest was measured on the radiographs by 3 calibrated blinded examiners using a digital caliper. RESULTS: The mean amounts of bone loss around the exposed and nonexposed implants were 0.46 ± 0.55 and 0.32 ± 0.46 mm, respectively, with no significant differences between the two groups. CONCLUSION: Wound dehiscence between the first- and second-stage surgeries may increase crestal bone loss in some cases but can be reduced by professional follow-ups and antibacterial treatments.

Effect of Periodontal Dressing on Wound Healing and Patient Satisfaction Following Periodontal Flap Surgery.

OBJECTIVES: It has been claimed that periodontal dressing reduces the risk of wound infection, bleeding and granulation tissue formation and improves tissue healing. This study sought to assess the effect of periodontal dressing on wound healing and patient satisfaction following periodontal flap surgery. MATERIALS AND METHODS: This clinical trial was conducted on 33 patients presenting to Hamadan University, School of Dentistry in 2012 whose treatment plan included two periodontal surgical procedures on both quadrants of the maxilla or mandible. The variables evaluated were severity of pain, bleeding, facial swelling and ease of nutrition experienced by patient during the first 3 days after surgery and inflammation, granulation tissue formation and gingival color at 7 and 14 days. Obtained data were analyzed using SPSS version 16.0 and R software and chi-square and t-tests. RESULTS: The mean (±SD) pain score was 1.73±1.153 and 2.79±1.933 in surgical sites with and without periodontal dressing, respectively and this difference was statistically significant (P=0.005). No significant difference was noted between sites with and without periodontal dressing in terms of swelling, bleeding, gingival consistency, granulation tissue formation, gingival color and ease of nutrition (P>0.05). CONCLUSION: According to the results of the present study, patients did not experience more bleeding, facial swelling or nutritional problems without periodontal dressing; however, the level of pain experienced was lower after surgeries with the use of periodontal dressing.

Comparison of Electric Toothbrush, Persica and Chlorhexidine Mouthwashes on Reduction of Gingival Enlargement in Orthodontic Patients: A Randomised Clinical Trial.

PURPOSE: To compare the efficacy of chlorhexidine, Persica mouthwash and electric toothbrushes in improving gingival enlargement in patients with fixed orthodontic appliances. MATERIALS AND METHODS: Seventy-two orthodontic patients with at least two sites of gingival enlargement were randomly allocated into four equal groups: 1) manual toothbrush; 2) electric toothbrush; 3) manual toothbrush+Persica mouthwash; 4) manual toothbrush+chlorhexidine mouthwash. All participants were instructed to brush their teeth at least twice a day. The subjects in groups 3 and 4 were instructed to use Persica or chlorhexidine according to the respective manufacturer's instructions. Bleeding on probing (BOP) index, gingival index (GI), O'Leary's plaque index (PI) and constructed hyperplastic index (HI) of all the subjects were measured in a blind manner at the start of the study and 2 weeks later. Changes of indices in the entire oral cavity and individual affected teeth were analysed with SPSS 16 using chi-square, ANOVA, ANCOVA, LSD and the paired t-test. RESULTS: In the entire oral cavity, there was a statistically significant improvement in indices in all the groups except for HI, which significantly improved only in group 4 (p=0.001). Data of individual teeth with hyperplastic gingiva showed significant reduction of all the variables except for HI in group 1 (p=0.08). No significant differences were found between groups 1 and 2 or between groups 3 and 4. CONCLUSION: The efficacy of Persica was similar to that of chlorhexidine in improving gingival conditions. None of the treatment modalities could reduce gingival enlargement to the clinically acceptable level of health.

High Insertion Torque and Peri-Implant Bone Loss: Is There a Relationship?

Because primary stability has a critical role in implant osseointegration, greater insertion torque is more desirable. However, excessive pressure on the peri-implant bone may lead to bone resorption. This study evaluates the effect of insertion torque on crestal bone level. Periapical radiographs of 136 bone-level implants were assessed in this retrospective cohort study. Sixty-four implants were inserted with high insertion torques (45-70 N/cm) and 72 implants were placed with a torque in the range of 20 to 30 N/cm. The distance between implant shoulder and proximal bone crest was measured on radiographs taken immediately after the insertion and compared to those calculated after uncovering surgeries (inserting the healing abutment). The mean bone resorption around implants placed with high and lower insertion torques was 0.33 and 0.4, respectively; thus, the difference between the two groups was insignificant (p = 0.88). High insertion torques (up to 70 N/cm) did not significantly increase bone resorption around implants.

Evaluation of IL-8 gene polymorphisms in patients with periodontitis in Hamedan, Iran.

BACKGROUND: Many environmental and genetic factors are known as factors that increase the susceptibility to periodontitis. As IL-8 is a chemokine that mediate the inflammatory process in periodontal disease, we decided to evaluate the effect of its polymorphism on chronic and aggressive periodontitis. MATERIALS AND METHODS: In this cross-sectional study DNA was isolated from the whole blood of 107 periodontitis patients and 199 healthy individuals. All samples were genotyped for the IL-8 polymorphisms using the polymerase chain reaction with sequence specific primers. The distribution of the interleukin-8 genotype and allele frequencies in control and disease groups was analyzed by the Chi-square test and a P-value of < 0.05 was considered statistically significant. RESULTS: The findings revealed that the allele and genotype frequencies of A2767T, T(1)1722T(2), and C781T polymorphism of IL-8 gene were not significantly differed between controls and patients. However, there was a significant difference in the genotype frequencies of IL-8 A251T (P < 0.0001), G396T (P < 0.0001), and C1633T (P < 0.0001) gene polymorphism between the patient and the control groups. Additionally, there was a significant difference in the genotype frequencies of C1633T (P < 0.05) polymorphism of IL-8 gene between the aggressive and chronic periodontitis. CONCLUSION: IL-8 gene polymorphism may be protective against periodontitis.