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Dental Materials and Techniques - Volume:6 Issue: 4, Autumn 2017

Journal of Dental Materials and Techniques
Volume:6 Issue: 4, Autumn 2017

  • تاریخ انتشار: 1396/07/11
  • تعداد عناوین: 8
  • Fatemeh Mazhari, Katayoun Safari, Fatemeh Mahmoudabadi * Pages 147-151
    To compare the efficacy of Mineral Trioxide Aggregate (MTA) and Modified Portland Cement (MPC) as pulpotomy medicaments in primary molars.
    A sample of 54 children 4 to 6 years old of age, who had at least one primary mandibular second molar that needed pulpotomy were randomly placed in MTA (n = 28) or MPC (n = 26) groups. After completing the pulpotomy procedures, the teeth received a stainless-steel crown. Clinical and radiographic successes/failures were blindly evaluated at 6 and 12 months, and Fisher's exact test was used to analyze the differences.
    At 6- and 12-month follow-ups, MTA and MPC had 100% clinical success rate. Radiographic success rates of MTA were 92.9% at 6 months and 89.3% at 12 months. While the rate for MPC group was 88.5% at both intervals. There was no statistically significant difference between the two groups.
    The results of this investigation showed that treatment success rate with MPC was comparable to MTA pulpotomy. However, additional clinical research that considers long-term follow-ups is required to test the usefulness of MPC in the pulpotomy treatment of primary teeth.
    Keywords: portland cement, mineral trioxide aggregate, primary molars, pulpotomy
  • Eshaghali Saberi, Abbas Mohammadi, Sediqe Ebrahimipour *, Sepideh Baniasadi Pages 152-158
    Background And Aim
    Root canal preparation with rotary instruments may cause dentinal cracks leading to tooth fracture. The aim of this study was to compare three different rotary systems ProTaper, RaCe and Niti Tee on formation of dentinal cracks following root canal preparation.
    Materials And Methods
    In this experimental study, 50 extracted mandibular first molars were selected. Teeth having roots with previous cracks and defects were excluded from the study. The crowns and distal roots of teeth were cut. Silicon impression material was used to simulate tooth PDL. The mesial roots were randomly prepared using ProTaper (up to F3) RaCe and Niti Tee systems (up to ≠30/0.06) in three groups of 15. Five teeth remained unprepared as the control group. The specimens were then sectioned horizontally in 3, 5 and 9 mm distances from the apex. Cracks exploration was done by digital stereomicroscope. The occurrence of dentinal cracks with different systems were statistically analyzed by chi-square test.
    Dentinal defects were observed in 3 (20%), 4 (26.7%) and 2 (13.3) of root canals following the preparation with ProTaper, Niti Tee and RaCe files, respectively. Two of the 3 defects in protaper group were as complete crack. The overall incidence of crack among the rotary files was 20%. No significant differences were found in defect formation between the three rotary systems (P>0.05).
    Under the condituion of this study Dentinal cracks were observed in all systems. The overall incidence of crack among the rotary files was 20%. Although more cracks were observed in NTiTee group, the differences were not significant.
    Keywords: Dentinal crack, root canal preparation, rotary instrumentation system, NiTi Tee, Protaper, RaCe
  • Shiva Sadeghi *, Ramin Tabari, Sepideh Hosseini Pages 159-162
    Thickness of a coronal seal barrier is an important factor for preventing microleakage. The aim of this in vitro study was to compare the sealing ability of two different thicknesses of calcium Enriched Mixture (CEM) cement as a coronal seal barrier.
    A total of 40 canals of extracted maxillary central incisors were instrumented and obturated using lateral compaction technique. The teeth were randomly divided into two experimental (N=15) and two control groups (N=5). For experimental groups, the obturation material was removed up to the experimental depths (2 and 3 mm) and were sealed with CEM. Sealing ability was evaluated by dye penetration method using pelikan ink and a stereomicroscope at x10 magnification and 0.01 mm accuracy. Data was analyzed using T-test and P
    The mean linear dye microleakage for the two thicknesses of CEM cement groups (2mm and 3mm) were 0.930 and 0.67 mm respectively. There was no statistically significant difference between the two groups (p
    under the condition of this in vitro study, coronal microleakage in 2mm thickness of CEM cement had no statistically significant difference with 3 mm thickness of the material.
    Keywords: sealing ability, coronal seal, CEM
  • Murtaza A. Kaderi *, K.B. Menaka, Renuka M. Metgud, Mugdha R. Gharat, Priyanka S. Naik, Jyoti M. Ajbani, Pooja P. Naik, Aditi Mahajani Pages 163-169
    Cyanoacrylate tissue adhesives have been used as a substitute to silk for intraoral wound closure. Placement of sutures provides a corridor for accumulation of microorganisms into tissue which leads to infection. Cyanoacrylate-based adhesives exhibit many properties of an ideal wound closure agent, minimizing the problems generated by suturing thread. The antimicrobial properties of cyanoacrylates have been extensively assessed in other fields of medicine. However, there is a dearth in the literature on the antibacterial effect of cyanoacrylates in oral environment against oral microflora.
    Aim: To assess the antibacterial properties of two commonly used formulations of cyanoacrylate tissue adhesives against oral pathogens.
    Materials And Methods
    Iso-amyl cyanoacrylate and a blend of n-butyl and 2-Octyl cyanoacrylates were applied on sterile filter paper discs and placed on culture plates. Plates for aerobic & anaerobic bacterial cultures were incubated in blood agar & Brain-Heart infusion agar respectively.Following incubation period, the bacterial inhibitory halos were measured in millimeters. In order to evaluate the bactericidal efficacy, samples were collected from the inhibitory halos and re-cultured on new bacterial culture plates.
    Antibacterial activity was assessed against five bacteria: A.actinomycetemcomitans, P.gingivalis, T.forsythia, L.amylovorus and S.aureus. Statistical analysis used: The data collected was analysed using Mann Whitney u test.
    Cyanoacrylates demonstrated potent inhibitory effects against all test organisms. The zones of inhibition against gram positive bacteria were found to be larger than gram negative bacteria. The bactericidal activity of Iso amyl cyanoacrylate was found to be more potent than n-butyl 2 octyl cyanoacrylate.
    Due to its potent antibacterial properties, cyanoacrylate tissue adhesives can be considered as appealing alternatives to silk sutures for intraoral wound closure and help prevent postoperative.
    Keywords: Cyanoacrylates, tissue adhesive, antibacterial, Periodontal Microflora, oral pathogens
  • Zahed Mohammadi, Luciano Giardino, Flavio Palazzi, Raffaele Paragliola, Simone Grandini, Hamid Jafarzadeh * Pages 170-175
    Aim: Most endodontic sealers show antimicrobial activity before setting, but most of them also lose this ability after setting. Addition of an antibiotic may affect the properties of sealers such as sealing ability, setting time, and so on. The aim of this study was to assess whether the addition of antibiotics (amoxicillin, doxycycline, and clindamycin) improves the sealing ability of AH 26 sealer.
    Materials And Methods
    Seventy extracted human mandibular premolars were used. After cleaning and shaping the canals, the teeth were divided into six groups: group 1: gutta-percha and AH 26 sealer, group 2: gutta-percha and AH 26 sealer皌牳✥詷, group 3: gutta-percha and AH 26 sealer橪ㆉ좥阩, group 4: gutta-percha and AH 26 sealer牘ꝵꦲ爩, group 5: gutta-percha without sealer (positive control), and group 6: gutta-percha and AH 26 sealer (the root surfacewere covered with nail varnish) (negative control). A microbial leakage model was used to assess the sealing ability.
    Group 2 had the greatest resistance against bacterial leakage. Furthermore, combining AH 26 sealer with amoxicillin and clindamycin increased mean leakage time compared to AH 26 sealer solely. However, the differences between groups 1 and 3 as well as between groups 1 and 4 were not statistically significant.
    Incorporating antibiotics especially doxycycline into AH 26 sealer increases its resistance against bacterial leakage.
    Keywords: AH26 sealer, Antibiotics, Bacterial leakage, Enterococcus faecalis
  • Rasul Sahebalam, Sara Hajian *, Tayebe Mokarami Pages 176-180
    Aim: As to the assessment of occlusal status pertaining to primary canines and molars, the latter is less within reach as it is difficult to guide jaws towards a centric occlusion while maintaining a vintage point in both direct and indirect observation.
    This study was originally intended to assess primary canine occlusion as a practical indicator in the evaluation of primary molar occlusion, which is otherwise less feasible in dental examination.
    Method and materials: A total of 281 healthy children (145 males and 136 females), with complete primary dentition and without erupted permanent teeth and serious caries were examined by a trained student of dentistry. Occlusal patterns of primary second molars were noted as flush terminal plane, distal step and mesial step and for primary canine as class I, class II and class III with regard to Angle’s classification.
    Overall, Class II canine occlusion seemed to have coincided with more than half of the flush terminal molar occlusions (62%), whereas class I was largely associated with mesial step molars (61.2%). This was also found to be applied to cases undergoing unilateral assessment. (p
    In the present study, a significant correlation between the primary canine and molar occlusal patterns (pImportance of study: the evaluation of primary canine occlusion can be used in preschool children as a simple practical method of predicting future discrepancies in the permanent dentition.
    Keywords: Primary dentition, occlusion, canine, molar, children, prospective cohort study
  • Somaye Ansari Moghadam, Siavash Zadfattah, Sirous Risbaf Fakour, Alireza Ansari Moghaddam, Mohammad Naebi * Pages 181-185
    Chronic periodontitis causes systemic inflammation and increases C-reactive protein (CRP). CRP has been implicated as a possible mediator of associating periodontitis and several systemic diseases. The aim of the present study was to investigate systemic levels of CRP in patients with chronic periodontitis in comparison to periodontally healthy individuals.
    Materials And Methods
    A total of 80 individuals were included in this study. 40 patients with severe chronic periodontitis aged 40, and 40 sex matched periodontally healthy subjects were recruited from the patients attending Dpartment of Periodontics, Faculty of Dentistry, Zahedan. Body Mass Index (BMI) was under 25 kg/m2 in all the patients and controls. Peripheral blood samples were taken and CRP levels were estimated in serum samples using the C - reactive protein – hs (CRP-hs) LATEX – High sensitivity (Biosystem S.A).
    CRP levels in women in the test group (3.64 + 2.77 mg/l) was significantly higher than the women in the control group (p
    Periodontitis results in higher systemic levels of CRP. Elevated inflammatory factor may increase inflammatory activity in atherosclerotic lesions and potentially increase the risk for cardiovascular events.
    Keywords: LATEX – high sensitivity_C – reactive protein_systemic inflammation_chronic periodontitis_healthy subjects
  • Mahshid Sheikhnezami, Nima Mokhber, Khosro Shamsian, Salman Saket, Hamid Jafarzadeh* Pages 186-190
    Horizontal root fracture (HRF) generally has a good prognosis of healing at fracture line after repositioning and flexible splinting. However, various factors such as delayed referral may unfavorably influence close reduction of firmly displaced coronal fragments and the long-term prognosis of healing at fracture line. Case 1: A 25-year-old woman with HRF in her maxillary central incisors was referred 1 week after trauma. Repositioning of the displaced coronal fragment was not successful for the left central incisor. Despite questionable prognosis for this case, reduction and flexible splinting was performed after removing it’s coronal fragment, minor curettage in alveolar socket and immediate replanting. Calcium hydroxide dressing and MTA plug placement for the coronal fragment were carried out after 1 and 3 weeks, respectively. The crown was restored and a minor permanent splint was applied after splint removal. Case 2: The above protocol was applied for a 17-year-old boy with HRF in his left maxillary central incisor. He referred 3 weeks after trauma with a firmed displaced coronal fragment. At four-year follow-up in both patients, the teeth were clinically in function and the patients were asymptomatic. The periapical radiographs revealed complete healing at fracture lines.
    Keywords: Case report, Dental trauma, Root fracture