فهرست مطالب

Journal of Islamic Dental Association of IRAN
Volume:28 Issue: 2, Spring 2016

  • تاریخ انتشار: 1395/09/26
  • تعداد عناوین: 6
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  • Gholam Reza Esfahanizade*, Zafar Mahdavi Izady, Anita Eyvazlou, Mohammad Pouyan Pages 48-51
    Background And Aim

    Making impression of several implants simultaneously for fabrication of dental prosthesis is challenging for many clinicians. Splinting can be performed for highly accurate impression making and better adaptation of prostheses. This study aimed to assess the effect of Impla and Duralay acrylic resin splinting materials on dimensional changes of direct implant impressions.

    Materials And Methods

    In this in vitro experimental study, a master model was fabricated using epoxy resin. Three fixtures were vertically placed with 15mm distance from each other. Impression copingswerescrewed and splinting was performed with Impla Fix and Duralay acrylic resin separately. Fourteen impressions were made of the splints and dimensional changes were determined by measuring distances in x, y and z axes on casts using coordinate measuring machine (CMM). Data were analyzed using t-test.

    Results

    The mean and standard deviation of change in Duralay and Impla groups were 28.078.68 and 257.39, respectively. Changes in x (P=0.746), y (P=0.772) and z (P=0.631) axes were slightly greater in use of Duralay acrylic resin but the differences were not statistically significant.

    Conclusion

    Impla splinting material is superior to Duralay acrylic resin due to smaller dimensional changes and easy use.

    Keywords: Dental Implants, Dental Impression Techniqu, Dental Prosthesis
  • Shahriar Emamikhah Abarghooii*, Mohsen Golparvar, Maryam Zare Jahromi Pages 52-56
    Background And Aim
    Dentistry is among the most stressful professions. Dentists’ occupational stress usually begins during their university education. This study aimed to assess the relationship between the level of stress experienced by dental students during endodontic treatment and their coping strategies.
    Materials And Methods
    This descriptive study was conducted on 204 fifth and sixth year dental students of Isfahan Islamic Azad University and Dental School of Isfahan University of Medical Sciences. The questionnaires used included 29 questions regarding level of stress experienced during endodontic treatment along with a coping strategies questionnaire, which were filled out by self-reporting. Data were analyzed using the Pearson’s correlation coefficient and multiple regression analysis.
    Results
    Among effective coping mechanisms, only conflict and ambiguity were negatively correlated with overall stress (P=0.002). Among ineffective coping mechanisms, anxiety, workload, conflict and ambiguity were significantly correlated with overall stress (P=0.001).
    Conclusion
    Coping mechanisms are directly correlated with level of stress of students such that effective coping mechanisms decrease stress. Male dental students experience higher level of stress due to ineffective coping mechanisms.
    Keywords: Stress, Physiological, Adaptation, Psychological, Dentistry, Root Canal Therapy
  • Mehrsa Paryab*, Hoseain Afshar, Bahman Seraj, Salar Shakibapoor, Mohammad Javad Kharazifard Pages 57-63
    Background And Aim
    Restoration of primary anterior teeth with severe caries extending to the gingival margin is challenging for many clinicians especially in uncooperative children. Resin modified glass ionomer cements (RMGICs) can be suitable for use in such cases since they require fewer application steps than composite resins. This study aimed to assess the fracture strength of severely damaged primary anterior teeth after their coronal build-up using RMGIC and composite resin.
    Materials And Methods
    This in vitro, experimental study was conducted on 40 primary teeth that met our inclusion criteria. After decoronization, they were cleaned and root canals were filled. In the coronal cavity, one layer of base was applied and an undercut was created in the canal wall above the base. The teeth were divided into two groups of 20 for coronal restoration. In group 1, etching, bonding, intracanal post fabrication and restoration with composite resin were carried out. In group 2, conditioning, intracanal post fabrication and restoration with Fuji II LC RMGIC were performed. After thermal cycles, fracture strength of teeth was measured and compared in the two groups using t-test.
    Results
    Fracture strength of teeth was not significantly different between two groups restored with composite resin (5.03±2.30 MPa) and RMGIC (5.67±2.38 MPa) (P>0.05)
    Conclusion
    In the post and crown build up of severely damaged primary anterior teeth with severe caries extending to the gingival margin, Fuji II LC RMGIC can be used as an alternative to composite resin especially in uncooperative children or treatment under general anesthesia.
    Keywords: Composite Resins, Fuji II LC cement, Glass Ionomer Cements, Tooth, Deciduous, Incisor, Post, Core Technique, Tooth Fractures
  • Esmaeil Yasini, Mansooreh Mirzaie*, Hamid Kermanshah, Elahe Habibi, Fariba Motevasselian Pages 64-71
    Background And Aim
    Fractured metal-ceramic restorations may be repaired with composite in some cases to postpone the fabrication of a new restoration. Knowledge about the bond strength can help predict the success rate of this treatment modality. The aim of this study was to assess the effect of two types of mechanical surface treatment of metal along with the use of different adhesive systems on bond strength of composite to a non-precious metal alloy.
    Materials And Methods
    In this in vitro experimental study, 110 metal discs were fabricated of nickel chromium alloy and were randomly divided into two groups of surface preparation with sandblasting (S) and bur (B). In each group, the samples were divided into five subgroups based on the adhesive system and composite resin used: Group NC: Z350 composite without application of adhesive; group AC: Alloy primer/Clearfil AP-X; group ZA: Z-Prime Plus/Aelite; group MT: Monobond Plus/Tetric N Ceram; group AZ: Adper Single Bond Plus/Z250. In the positive control group (PC), metal discs were covered with feldspathic porcelain. All samples were then subjected to 1000 thermal cycles and shear bond strength was measured. Data were analyzed using one-way ANOVA, two-way ANOVA and Tukey’s HSD test (P
    Results
    The interaction effect of type of surface treatment and type of adhesive system on bond strength was significant (P
    Conclusion
    Type of surface preparation and adhesive affect the bond strength. Surface preparation by sandblasting or bur combined with the use of Adper Single Bond Plus and also combination of Z-Prime Plus adhesive and sandblasting yielded the highest bond strength value.
    Keywords: Dental Bonding, Adhesives, Shear Strength, Composite Resins, Metal Ceramic Alloys
  • S.Shojaeddin Shayegh, Parviz Amini, Kaveh Yaghmai, Farhood Massoumi, Kamyar Abbasi* Pages 72-77
    Background And Aim
    Several methods are available for intraoral repair of chipped porcelain restorations by composite resin. Also, there is still controversy regarding the best method of porcelain repair in terms of bond strength and cost effectiveness. This study aimed to compare three methods of porcelain surface treatment on shear bond strength (SBS) of composite to porcelain.
    Materials And Methods
    This in vitro, experimental study was conducted on 30 porcelain blocks with a metal base in three groups. In group 1, porcelain surface was etched with hydrofluoric (HF) acid and silanized. After the application of bonding agent, several composite increments with 2mm thickness were applied on the porcelain surface. In group 2, porcelain surface was sandblasted with 50µaluminum oxide particles, etched and silanized. In group 3, grooves with 2mm length and 0.5 mm depth were created on the porcelain surface. The surface was then etched and silanized. Bonding agent and composite were then applied. The samples were then mounted in acrylic resin, stored in water for one week and subjected to thermocycling. The SBS was then measured using a universal testing machine. The SBS data were compared among the three groups using one-way ANOVA.
    Results
    The mean SBS was 9.13±6.09, 12.71±9.82 and 11.44±7.37 MPa in groups 1-3, respectively. No significant difference in bond strength was noted among the three groups (P>0.05).
    Conclusion
    No significant difference exists among the three surface treatment methods evaluated in this study in terms of SBS of composite to porcelain.
    Keywords: Dental Porcelain, Shear Strength, Composite Resins
  • Farzaneh Agha Hosseini*, Mahdieh Sadat Moosavi, Maryam Sadat Sadrzadeh Afshar, Nafiseh Sheykh Bahaei Pages 78-85
    Background And Aim
    Oral lichen planus (OLP) is a chronic inflammatory lesion. Psychological stress occurs when someone senses that environmental demands exceed his/her adaptive capability. Stress, anxiety, and depression have frequently been mentioned as possible factors related to the development of OLP, although this association remains controversial. In most studies, a positive correlation was found between psychological stress and OLP, although some found no significant association. In this review, we assess the possible role of psychological stress in the etiopathogenesis of OLP.
    Materials And Methods
    The methodological approach of this study was to search major databases from 1985-2014, using "oral lichen planus"," stress", "anxiety", "depression" and "psychological disorder” as search terms.
    Results
    A total of 45 scientific papers and abstracts in English were reviewed, and 10 articles met the necessary requirements. Stress evaluation methods of these articles were questionnaire, genetic polymorphisms at DNA level, measurement of body substances like hormones, and effect of drug therapy of psychiatric disorders on OLP patients. In order to include a study, OLP in patients must have been proven by clinical and histopathological criteria. Exclusion criteria were not explicit stating the OLP diagnosis, an inadequate number of the test subject in experimental and control groups, discrepancy (inconsistency) in sex and age between the case and control groups, and unreliable method of stress measurements.
    Conclusion
    Higher levels of stress in patients with OLP were confirmed. Reducing psychological stress and well-being of patients is an important factor that should be considered in the treatment of OLP.
    Keywords: Stress, Psychological, Lichen planus, Oral, Anxiety