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Dental Research Journal - Volume:13 Issue: 2, Mar 2016

Dental Research Journal
Volume:13 Issue: 2, Mar 2016

  • تاریخ انتشار: 1395/01/16
  • تعداد عناوین: 14
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  • Claudio Poggio, Marco Pigozzo, Matteo Ceci, Andrea Scribante, Riccardo Beltrami, Marco Chiesa Page 91
    Background
    The purpose of this study was to evaluate the influence of three different luting protocols on shear bond strength of computer aided design/computer aided manufacturing (CAD/CAM) resin nanoceramic (RNC) material to dentin.
    Materials And Methods
    In this in vitro study, 30 disks were milled from RNC blocks (Lava Ultimate/3M ESPE) with CAD/CAM technology. The disks were subsequently cemented to the exposed dentin of 30 recently extracted bovine permanent mandibular incisors. The specimens were randomly assigned into 3 groups of 10 teeth each. In Group 1, disks were cemented using a total‑etch protocol (Scotchbond™ Universal Etchant phosphoric acid Scotchbond Universal Adhesive RelyX™ Ultimate conventional resin cement); in Group 2, disks were cemented using a self‑etch protocol (Scotchbond Universal Adhesive RelyX™ Ultimate conventional resin cement); in Group 3, disks were cemented using a self‑adhesive protocol (RelyX™ Unicem 2 Automix self‑adhesive resin cement). All cemented specimens were placed in a universal testing machine (Instron Universal Testing Machine 3343) and submitted to a shear bond strength test to check the strength of adhesion between the two substrates, dentin, and RNC disks. Specimens were stressed at a crosshead speed of 1 mm/min. Data were analyzed with analysis of variance and post‑hoc Tukey’s test at a level of significance of 0.05.
    Results
    Post‑hoc Tukey testing showed that the highest shear strength values (P
    Conclusion
    Within the limitations of this in vitro study, conventional resin cements (coupled with etch and rinse or self‑etch adhesives) showed better shear strength values compared to self‑adhesive resin cements. Furthermore, conventional resin cements used together with a self‑etch adhesive reported the highest values of adhesion.
    Keywords: Adhesive cements, computer aided design, computer aided manufacturing ceramic, shear bond strength
  • Jayachandran Perayil, Keerthy S. Menon, Raja Biswas, Angel Fenol, Rajesh Vyloppillil Page 98
    Background
    This study was performed to evaluate and compare the clinical and antimicrobial efficacy of subgingival irrigation with tetracycline and povidone‑iodine as an adjunct to nonsurgical periodontal therapy.
    Materials And Methods
    Twenty subjects with chronic moderate periodontitis were recruited in this split‑mouth study with probing pocket depth of >3 and ≤5 mm and clinical attachment loss of 3–4 mm in relation to 16, 36, and 46. In each subject, three selected periodontal pockets were assigned to receive one out of three irrigants (1) sterile water (control) in 16; (2) tetracycline at 10 mg/ml in 36; (3) 2% povidone‑iodine in 46, and these sites were designated as Group A, Group B, and Group C, respectively. Plaque score, gingival score, pocket probing depth, and clinical attachment level were evaluated before treatment and at 1 and 3 months posttreatment. Multiplex polymerase chain reaction was used to detect Porphyromonas gingivalis and Tannerella forsythensis which have been implicated as the major risk factors for periodontal disease. Subgingival plaque collected before treatment and at 1 and 3 months posttreatment. Data were analysed using ANOVA and repeated measure ANOVA. Results were considered significant if P
    Results
    Clinical and microbiological parameters were reduced posttreatment, the reduction being significantly higher in Group B compared to Group C.
    Conclusion
    It can be concluded that chemical and mechanical therapies were of slight benefit in the treatment of chronic moderate periodontitis, and there was an adjunctive effect of significance when scaling and root planing was combined with a single subgingival irrigation with tetracycline or povidone‑iodine in lower concentration.
    Keywords: Polymerase chain reaction, povidone‑iodine, subgingival irrigation, tetracycline
  • Renato Roperto, Anna Akkus, Ozan Akkus, Lisa Lang, Manoel Damiao Sousa‑, Neto, Sorin Teich, Thiago Soares Porto Page 117
    Background
    The aim of this study was to determine the microtensile bond strength(μTBS) of ceramic and composite computer aided design‑computer aided manufacturing (CAD‑CAM)blocks bonded to dentin using different adhesive strategies.
    Materials And Methods
    In this in vitro study, 30 crowns of sound freshly extracted human molars were sectioned horizontally 3 mm above the cementoenamel junction to produce flat dentin surfaces. Ceramic and composite CAD/CAM blocks, size 14, were sectioned into slices of 3 mm thick. Before bonding, CAD/CAM block surfaces were treated according to the manufacturer’s instructions. Groups were created based on the adhesive strategy used: Group 1 (GI) – conventional resin cement total‑etch adhesive system, Group 2 (GII) – conventional resin cement self‑etch adhesive system, and Group 3 (GIII) – self‑adhesive resin cement with no adhesive. Bonded specimens were stored in 100% humidity for 24h at 37°C, and then sectioned with a slow‑speed diamond saw to obtain 1 mm × 1 mm × 6 mm microsticks. Microtensile testing was then conducted using a microtensile tester. μTBS values were expressed in MPa and analyzed by one‑way ANOVA with post hoc (Tukey) test at the 5% significance le vel.
    Results
    Mean values and standard deviations of μTBS (MPa) were 17.68 (±2.71) for GI/ceramic; 17.62 (±3.99) for GI/composite; 13.61 (±6.92) for GII/composite; 12.22 (±4.24) for GII/ceramic; 7.47 (±2.29) for GIII/composite; and 6.48 (±3.10) for GIII/ceramic; ANOVA indicated significant differences among the adhesive modality and block interaction (P
    Conclusion
    Cementation of CAD/CAM restorations, either composite or ceramic, can be significantly affected by different adhesive strategies used.
    Keywords: Adhesion, ceramic, composite resin, computer aided design, computer aided manufacturing
  • Pouran Samimi, Vahid Alizadeh, Kamyar Fathpour, Hamid Mazaheri, Vajihosadat Mortazavi Page 124
    Background
    The current study evaluated the micro‑shear bond strengths of a new low‑shrinkage composite resin to dentin.
    Materials And Methods
    In this in‑vitro study, 70 extracted premolars were assigned to one of seven groups (n = 10): Group 1: OptiBond Solo Plus (Opt; Kerr); Group 2: SE Bond (SE; Kuraray); Group 3: Silorane System Adhesive (SSA; 3M ESPE); Group 4: OptiBond Solo Plus LS Bond (Opt LS); Group 5: SE Bond LS Bond (SE LS); Group 6: OptiBond Solo Plus (Opt Po); and Group 7: SE Bond (SE Po). Occlusal dentin was exposed and restored with Filtek LS (3M ESPE) in groups 1 to 5 and Point 4 (Kerr) in groups 6 and 7. After thermocycling (1000 cycles at 5/55°C), micro‑shear bond test was carried out to measure the bond strengths. The results were submitted to analysis of variance and post hoc Tukeytests (P
    Results
    Two‑way ANOVA showed no significant differences between the two types of composite resin (P = 0.187), between bonding agents (P = 0.06) and between composite resin and bonding agents (P = 0.894). Because P value of bonding agents was near the significance level, one‑way ANOVA was used separately between the two composite groups. This analysis showed significant differences between silorane composite resin groups (P = 0.045) and Tukey testshowed a significant difference between Groups 4 and 5 (P = 0.03).
    Conclusion
    The application of total‑etch and self‑etch methacrylate‑based adhesives with and without use of a hydrophobic resin coating resulted in acceptable bond strengths.
    Keywords: Low, contraction, composite resins, bonding agents, micro, shear, bond, strength
  • Laura Yueh‑, Guey Huang, Boyen Huang Page 132
    Background
    This study aimed to investigate dentists’ supply and practice patterns following the implementation of the global budget system in Taiwan.
    Materials And Methods
    Data of reimbursement claims, municipal socioeconomic status and dental manpower were collected from the National Health Insurance administration, the Ministry of Internal Affair, and the Ministry of Health and Welfare, respectively. A multivariate linear regression method was used for data analysis.
    Results
    A municipality that reported a higher percentage of tertiary educated population (t = 3.718, P
    Conclusion
    This study has demonstrated a stabilizing effect of the global budget system on dynamics of dental manpower in Taiwan. A relationship between HHI and dentists’ move‑out rate has been found. The relationship between municipal socioeconomic status and the density of dentists has also been confirmed. In addition, reduced utilization of amalgam restorations was accompanied by increased utilization of tooth‑colored material restorations. Further investigations are indicated.
    Keywords: Amalgam, composite resins, dentist, global, budget, health insurance, Herfindahl, Hirschman Index
  • Zahra Heidari, Hamidreza Mahmoudzadeh, Sagheb, Mohammad Hashemi, Somayeh Ansarimoghaddam, Nadia Sheibak Page 139
    Background
    The association between interleukin‑6 (IL‑6) (‑174G/C) gene polymorphismsand level of tissue breakdown and periodontal disease progression is unknown. The present study investigated quantitative parameters of interdental papilla in chronic periodontitis (CP) patients with IL‑6 (‑174G/C) gene polymorphisms.
    Materials And Methods
    Sixty gingival samples were studied. After determination of IL‑6 (‑174G/C) gene polymorphisms using a tetra‑primer amplification refractory mutation system‑polymerase chain reaction (T‑ARMS‑PCR) technique, 45 gingival tissue samples of CP patients (GG and GC genotypes) were considered as case groups. Fifteen control samples were also collected from healthy individuals. After tissue processing, interdental gingival tissues were exhaustively sectioned into 4 μm‑thick sections. Ten to thirteen sections were sampled by systematic uniform random sampling and stained with Masson trichrome, and the volume density (Vv) of the gingival components was estimated using Cavalier’s point counting method. Statistical analysis was performed by Student t‑test to compare differences between groups. The significance level was set at P
    Results
    There were statistically significant differences in the Vv of epithelium, connective tissue, collagenous and non‑collagenous matrix, and blood vessels between the control and CP groups (P 0.05).
    Conclusion
    Results of the current study showed that there was no association between IL‑6 (‑174G/C) gene polymorphisms and quantitative parameters of interdental papilla in CP patients.
    Keywords: Chronic periodontitis, genes, gingiva, interleukin‑6, polymorphism
  • Yeliz Guven, Yelda Kasimoglu, Elif Bahar Tuna, Koray Gencay, Oya Aktoren Page 145
    Background
    Talon cusp is a rare dental anomaly characterized by a cusp‑like projection, often including the palatal surface of the affected tooth. The aim of the present study was to investigate the prevalence and characteristics of talon cusps in a group of Turkish children.
    Materials And Methods
    The study population consisted of 14,400 subjects who attended the clinics of the Department of Pediatric Dentistry at the Istanbul University, Istanbul, Turkey . Subjects ranged in age from 1 to 14 years with a mean age of 10.5 ± 2.55 years. Talon cusps were mainly categorized by visual examination according to the classification of Hattab et al. The distribution and frequency of talon cusps were calculated with respect to dentition type, tooth type, talon type, the affected surface, associated dental anomalies, and clinical complications. Statistical analysis included descriptive statistics, frequencies, and crosstabs with Chi‑square analysis.
    Results
    Talon cusps were detected in 49 subjects (26 males and 23 females) of 14,400 0.34%). A total of 108 teeth showed talon cusps. Distribution of talon cusps according to gender showed no statistically significant differences. The incidence of talon cusps was found to be greater in maxillary lateral incisors (53.7%) than central incisors (29.62%). Regarding the type of talon cusp, 47.22% of teeth showed a Type III talon cusp, whereas 30.55% of teeth demonstrated a Type II talon and 22.22% of teeth demonstrated a Type I talon cusp. Nine patients (18.36%) with talon cups also exhibited other developmental dental anomalies. Clinical complications associated with talon cusps were detected as caries formation and occlusal interference.
    Conclusion
    This is the most comprehensive study of the prevalence of talon cusps in Turkish population using the largest sample size to date. Also, taurodontism associated with a talon cusp has been reported here for the 1st time. Clinical complications associated with talon cusps need more investigations.
    Keywords: Accessory, developmental anomaly, talon, tooth
  • Rokhsareh Sadeghi, Maryam Babae, S. Asghar Miremadi, Fatemeh Mashadi Abbas Page 151
    Background
    Alveolar ridge preservation could be performed immediately following tooth extraction to limit dimensional changes of alveolar process due to bone resorption. The aim of this study was to compare the clinical and histologic outcomes of socket preservation using two different graft materials; deproteinized bovine bone mineral (DBBM) and demineralized freeze‑dried bone allograft (DFDBA) with absorbable collagen membrane.
    Materials And Methods
    Twenty extraction sockets in 20 patients were randomly divided into 2 treatment groups: 10 sockets were augmented with DBBM and collagen membrane whereas 10 sockets were filled with DFDBA and covered by collagen membrane. Primary closure was achieved over extraction sockets by flap advancement. Horizontal and vertical ridge dimensional changes were assessed at baseline and after 4–6 months at the time of implant placement. For histological and histomorphometrical analysis, bone samples were harvested from the augmented sites with trephine during implant surgery. All data were analyzed using SPSS version 18 (α=0.05).
    Results
    Clinical measurements revealed that average horizontal reduction was 2.3 ± 0.64mm for DFDBA and 2.26 ± 0.51 mm for DBBM. Mean vertical ridge resorption at buccal side was 1.29 ± 0.68 mm for DFDBA and 1.1 ± 0.17 mm for DBBM. Moreover, mean vertical ridge reduction at lingual site was 0.41 ± 0.38 mm and 0.35 ± 0.34 mm for DFDBA and DBBM, respectively. No significant differences were seen between two groups in any of those clinical parameters. Histologic analysis showed statistically significant more new bone deposition for DFDBA compared to DBBM (34.49 ± 3.19 vs. 18.76 ± 3.54) (P
    Conclusion
    Based on the findings of this study, both materials have positive effect on alveolar ridge preservation after tooth extraction, but there was more new bone formation and less residual graft particles in DFDBA group than in DBBM group.
    Keywords: Collagen, membrane, extraction, socket, graft, material, preservation
  • Niloufar Khodaeian, Mansour Rismanchian, Ali Behzadi, Fariba Jowkar Page 160
    Background
    Questionnaire is a suitable tool for evaluating the subjective masticatory function in edentulous patients. However, there is no validated Persian version of masticatory function questionnaire. The aim of this study was to evaluate the psychometric properties of the translated Persian version of the quality of masticatory function (QMF) questionnaire in terms of validity and reliability.
    Materials And Methods
    After translation of QMF questionnaire to Persian, its validity was evaluated by four expert prosthodontists. The tool was applied on 62 complete denture wearers (31 men and 31 women, mean age 64.85 ± 1.98 years, mean time of edentulism 12.17 ± 3.21 years) via face‑to‑face interviews. Cronbach’s alpha coefficient was used to measure internal consistency. Construct validity was analyzed using exploratory factor analysis. The Spearman’s correlation coefficient between the summary scores of the tool and the years of edentulism and sex was also calculated for concurrent validity ( = 0.05).
    Results
    It has been found that the Persian version of the questionnaire had an acceptable reliability ( = 0.910). Exploratory factor analysis extracted five domains: Masticatory problems with dentures, problems while consuming apple and carrot, meat products, fruits and vegetables, and changes need for better swallowing. A correlation was found between the tool scores and the years of edentulism (P = 0.001), but there was no correlation between sex and the tool scores (P = 0.841).
    Conclusion
    The Persian version of QMF questionnaire for edentulous patients showed acceptable validity and reliability but further studies are needed to verify this tool.
    Keywords: Dentures, edentulous, mastication, questionnaire
  • B. R. Chandra Shekar, Ramesh Nagarajappa, Richa Jain, Rupal Singh, Rupesh Thakur, Suma Shekar Page 168
    Background
    The aim of this in vitro study was to assess antimicrobial efficacy of Acacia nilotica, Murraya koenigii (L.) Sprengel, Eucalyptus hybrid, Psidium guajava extracts, and their combination on Streptococcus mutans and Lactobacillus acidophilus.
    Materials And Methods
    The branches of four plants were collected, identified, and authenticated by a taxonomist. The plants were rinsed in water, healthy leaves were separated and shade dried over a period of 3–4 weeks. Soxhlet apparatus using ethanol was employed for extraction procedure. The combinations of plant extracts were prepared by mixing equal quantities of 10% solutions of each of these extracts. 0.2% chlorhexidine and dimethyl sulfoxide were used as positive and negative controls, respectively. The antimicrobial efficacy testing was done using agar well‑diffusion method under anaerobic conditions. The mean diameter of inhibition zone was computed and compared between different categories using one‑way analysis of variance and Tukey’s post‑hoc test. A qualitative assay was carried out to identify the various phytochemical constituents in the plants. The data was assessed by SPSS version 20. The statistical significance was fixed at 0.05.
    Results
    All the plants extracts and their combinations inhibited S. mutans and L. acidophilus. However, the quadruple combination of A. nilotica M. koenigii (L.) Sprengel Eucalyptus hybrid P. guajava produced the maximum inhibition zone (23.5 ± 2.2 mm) against S. mutans. Although, 0.2% chlorhexidine produced the highest inhibition zone against L. acidophilus (18.8 ± 1.2 mm), A. nilotica extract produced maximum inhibition among the various plant extracts and their combinations (14.1 ± 1.8 mm).
    Conclusion
    All the individual plant extracts and their combinations were effective against S. mutans and L. acidophilus. These could be tried as herbal alternates to chlorhexidine. However, these in vitro results have to be further evaluated for any toxicity of the polyherbal combinations in animal models and effectiveness has to be assessed using in vivo studies on humans.
    Keywords: Acacia, nilotica, Eucalyptus, hybrid, Lactobacillus acidophilus, Murraya, koenigii (L.) Sprengel anomaly, Psidium guajava, Streptococcus mutans
  • Mohammad Reza Malekipour, Farzaneh Shirani, Mehrnoush Ebrahimi Page 174
    Background
    The purpose of this study was to evaluate the effect of washing water temperature on the micro‑shear bond strength (μSBS) of composite resin to dentin using a two‑step etch‑and‑rinse system and a two‑step self‑etching system.
    Materials And Methods
    In this in vitro study, the intact dentins of buccal and lingual surfaces of healthy third molars were exposed. Dentin surfaces were rinsed with different temperatures of distilled water (20 s) before applying Single Bond (SB) or Clearfil SE Bond(SE). After applying the adhesive, composite cylinders (0.8 mm diameter and 1 mm length) were bonded to the teeth surfaces. After storing the specimens in 37°C distilled water for 48 h and thermocycling, μSBS test was done. Data were analyzed using analysis of variance, post hoc Tukey tests, paired samples t‑test, and Fisher exact test (α = 0.05).
    Results
    Temperature and interaction of temperature and type of bonding agent affected the bond strength. The bond strength of SB groups was significantly higher at 50°C washing than 5°C (P = 0.003) and 22°C (P = 0.019), but no significant difference was observed between SE groups. The bond strength of SE was significantly higher at 22°C than that of SB (P = 0.031), whereas the bond strength of SB was significantly higher at 50°C than that of SE (P = 0.007).
    Conclusion
    The use of high‑temperature washing water is an appropriate method to enhance bond strength in etch‑and‑rinse systems.
    Keywords: Bond, strength, dentin‑bonding agents, temperature, washing water
  • Kumar Chandan Srivastava, Ravi David Austin, Deepti Shrivastava Page 181
    Background
    Imbalances between the oxidant–antioxidant status have been implicated in the pathogenesis of several diseases, including cancer. The aim of this study was to evaluate the extent of lipid peroxidation and antioxidants in the tissue samples of oral squamous cell carcinoma (OSCC) patients of different clinical stages in comparison with the healthy controls.
    Materials And Methods
    A case‑control study was designed with 20 new histopathologically proven oral carcinoma patients and an equal number of age, sex, and tobacco chewing habit matched healthy subjects. Their tissue samples were subjected to evaluation of lipid peroxidation product and antioxidant enzymes, namely, superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and glutathione peroxidase (GPx) using spectrophotometric methods. The data are expressed as mean ± standard deviation. The statistical comparisons between the study groups were performed by independent Student’s unpaired t‑test and one‑way analysis of variance. Post‑hoc analysis was performed for within study group comparisons. Karl Pearson correlation was performed for the biochemical parameters within the group and between the groups. For statistically significant correlations, simple linear regression was performed using SPSS (α=0.05).
    Results
    Significant reduction in lipid peroxidation (P
    Conclusion
    Reduced lipid peroxidation and increased activity of reduced GSH and GPx provides the suitable environment for the local growth and invasion of the tumor and metastasis in the later stages. Among the antioxidant enzymes, GSH reductase appears to have a profound role in carcinogenesis and thus it can be considered as potential prognostic marker.
    Keywords: Antioxidants, lipid peroxidation, oral cancer, oxidative stress
  • Mohammad Jafarian, Farshid Rayati, Elnaz Najafi Page 188
    Successful treatment of a large implant periapical lesion (IPL) that caused paraesthesia and perimandibular abscess. IPL is a pathologic phenomenon that rarely involves implants. This event first described in 1992 with an incidence rate of 0.26–9.9% and the origin is not well known. The most likely suggested causes are presence of preexisting bone pathology, contamination of implant surface, bone overheating during implant surgery, vascular ischemia, excessive tightening of the implant, fenestration of the buccal plate and different implant surface designs. In the present case report, we describe relatively large periapical lesions involving several implants caused severe abscess accompanied by transient inferior alveolar nerve paraesthesia and its successful management. A brief review of the literature and a discussion of possible causes and different treatment plans are also included.
    Keywords: Implant periapical lesion, paraesthesia, perimandibular abscess
  • Shaik Sameeulla, Jayam Raviraj, Suresh Dirasantchu, Suman S. Venkata Page 193
    Ellis–van Creveld (EVC) syndrome, a form of skeletal and chondroectodermal dysplasia, is an autosomal recessive disorder characterized by a tetrad of disproportionate dwarfism, postaxial polydactyly, ectodermal dysplasia, and heart defects. In the present article, we hereby present a case of a 13‑year‑old girl of Indian ethnicity with EVC syndrome with a remarkable number of classical oral and dental features, with unusual findings such as taurodontism and talons cusp. Such dental findings were reported in few cases only. Despite the fact that oral manifestations play an important role in the diagnosis of EVC, only a few detailed reports have been published in the dental literature.
    Keywords: Ellis–van Creveld syndrome, polydactyly, taurodontism