فهرست مطالب

Journal of Dental Research, Dental Clinics, Dental Prospects
Volume:12 Issue: 3, Summer 2018

  • تاریخ انتشار: 1397/06/02
  • تعداد عناوین: 12
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  • Ravi Bhujbal _Neelima A Malik _Nilesh Kumar _Suresh KV* _Mushtaq I Parkar _Jeevan MB Pages 153-158
    Background
    Surgical removal of mandibular third molars results in pain, swelling and bony defects, causing prolonged postoperative recovery. The growth factors present in platelet-rich plasma (PRP) can accelerate the healing, thereby shorten-ing postoperative recovery period. This study was undertaken to evaluate the role of PRP in postoperative socket healing, pain, swelling and bone regeneration following surgical removal of impacted mandibular third molars.
    Methods
    The present case‒control study was conducted on 20 patients with identical bilateral mandibular third molar im-paction. PRP was placed randomly on one side of 3rd molar extraction socket and the contralateral side was used as control. Evaluation of soft tissue healing, pain, swelling and radiologic bone density was carried out.
    Results
    Soft tissue healing was better in the PRP compared to the control site. Immediate postoperative assessment of pain scores showed no significant difference between the two groups (Mann-Whitney U test). On the 7th day, pain scores were lower in case site compared to the control site. Measurement of swelling on the 1st, 3rd and 7th day showed statistically significant differences between the case and control sites (P<0.0001). Postoperative mean bone density at the 3rd and 6th postoperative months was significantly higher in the case site compared to the control site (P=0.00001).
    Conclusion
    The results showed an improvement in wound healing and swelling and an increase in the bone density at PRP site. The growth factors in PRP would improve the hard and soft tissue healing 3 months after molar surgery.
    Keywords: Extraction, platelet-rich plasma, soft tissue healing, pain, swelling, third molar
  • Amir Reza Babaloo, Adileh Shirmohammadi, Siamak Sandoghchian , Ashkan Kamalzadeh* , Shima Ghasemi Pages 159-165
    Background
    Periodontitis is an infectious and inflammatory disease of the supporting tissues of the tooth caused by specific microorganisms or a group of microorganisms and, if not treated, leads to progressive degradation of the supporting tissues and subsequent loss of the teeth affected. The aim of this study was to evaluate the effects of IL-36γ on periodontitis by enhancing the TLR4 and MAPK signaling pathways.
    Methods
    In this pilot study, 50 patients with generalized moderate-to-severe chronic periodontitis and 50 individuals with healthy periodontium, who were candidates for crown lengthening (CL), were selected based on inclusion criteria. The tissue samples were taken during pocket depth surgery (for the test group) and CL surgery (for the control group). The macrophage cells of the inflammatory tissues were extracted and stimulated by TLR4 proteins in a time-dependent manner; then IL-36γ levels in macrophages were investigated. Data were analyzed using descriptive statistics (means ± standard deviations and frequency percentages). Repeat measurement test was used to compare IL36γ expression in MAPK and TLR4 pathways at different time intervals. ANCOVA was used to compare IL36γ expression at different time intervals between the two path-ways. Statistical analysis was performed using SPSS 17 at a significance level of P<0.05.
    Results
    The results of the current study showed a significant relation between TLR4 and IL-36γ (P<0.001); in tissues with generalized moderate-to-severe chronic periodontitis, there was a significant relation between the condition and IL-36γ (P<0.0001). This study also showed that TLR4 and MAPK levels increased in the presence of IL-36γ.
    Conclusion
    According to the present study, it was concluded that IL-36γ concentrations increased in periodontitis, which could trigger MAPK and TLR4 pathways.
    Keywords: ELISA, immunofluorescence, periodontitis, western blot
  • Vrushali N. Lathiya* , Abhay P. Kolte , Rajashri A. Kolte , Dhawal R. Mody Pages 166-173
    Background
    This study evaluated the effect of periodontal therapy on mucous membrane thickening in maxillary sinus in chronic periodontitis patients using radiovisiography (RVG) and cone-beam computed tomography (CBCT).
    Methods
    The study population included 30 patients diagnosed with chronic periodontitis, exhibiting bilateral mucosal thick-ening of maxillary sinus. The selected sites were randomly assigned to group I (control group - not receiving periodontal therapy) and group II (test group - receiving periodontal therapy). The clinical parameters and mucosal thickening of the maxillary sinus were evaluated at baseline and after 9 months.
    Results
    There was a significant decrease in the PPD, CAL as well as mucosal thickening in group II while, group I showed an increase in these parameters. In group II at the end of 9 months the mean mucosal thickening reduction as assessed by CBCT was 0.76±0.18, 0.73±0.24, 0.88±0.42 and 1.13±0.43 mm at the most anterior point (AP), the most posterior point (PP), the mid-point (MP), point of maximum thickness (MT) as well as in the length of the thickened mucosal lining, respectively.
    Conclusion
    The results of our study indicated a reduction in the mucosal thickening of the maxillary sinus after surgical periodontal therapy. The trial was registered with the Clinical Trial Registry of India (Trial REF/ 2016/02/010805).
    Keywords: Maxillary sinus, mucosal thickening, periodontitis, periodontal surgery
  • Francesco Guido Mangano* , Sina Ghertasi Oskouei , Ana Paz , Natale Mangano , Carlo Mangano Pages 174-182
    Background
    Since osseointegration depends on bone metabolism, low levels of vitamin D in the blood may negatively affect bone formation around dental implants. To date, only a few studies have investigated the possible connection between serum levels of vitamin D and early dental implant failure (EDIF), i.e. failure that occurs within 4 months after placement, before the connection of the prosthetic abutment. The aim of this study was to investigate whether there is a relationship between low serum levels of vitamin D and EDIF.
    Methods
    Data used for this retrospective study were derived from the records of a private dental clinic. Inclusion criteria were patients who had been treated with dental implants, inserted with a submerged technique from January 2003 to December 2017. EDIF was the outcome of this study. Chi-squared test was used to investigate the effect of patient-related variables (age, gender, smoking habit, history of periodontal disease and serum levels of vitamin D) on EDIF.
    Results
    Originally, 885 patients treated with 1,740 fixtures were enrolled in this study. Overall, 35 EDIFs (3.9%) were reported. No correlation was found between EDIF and the patients' gender (P=0.998), age (P=0.832), smoking habit (P=0.473) or history of periodontal disease (P=0.386). Three EDIFs (11.1%) were reported in 27 patients with serum levels of vitamin D <10 ng/mL, 20 EDIFs (4.4%) in 448 patients with levels between 10 and 30 ng/mL, and 12 EDIFs (2.9%) in 410 patients with levels >30 ng/mL. Although there was a clear trend toward an increased incidence of EDIF with lowering of serum vitamin D levels, no statistically significant difference (P=0.105) was found among these three groups.
    Conclusion
    Within its limitations (retrospective design, low number of patients with severe blood levels of vitamin D enrolled), this study failed to demonstrate a significant relationship between low serum levels of vitamin D and increased risk of EDIF. However, since a dramatic increase in EDIFs with lowering of vitamin D levels in the blood has been reported, further clinical studies with appropriate design (prospective or randomized controlled studies on a larger sample of severely deficient patients) are needed to better investigate this topic.
    Keywords: Vitamin D, failures, implants, infections, osseointegration
  • Hakimeh Siadat, Hossain Najafi, Marzieh Alikhasi, Babak Falahi , Elaheh Beyabanaki* , Farid Zayeri Pages 183-189
    Background
    The implant connection type might affect microleakage and screw loosening in two-piece implants. The aim of this study was to measure microleakage and screw loosening of two connections of Noble Biocare implant system before and after cyclic loading.
    Methods
    Twelve samples were categorized into two groups: external hexagon (Branemark) and internal hexagon connection (Noble Active) and two implants as controls. The abutments were tightened to a 35 Ncm torque. Initial torque loss (ITL) was measured five minutes after retightening the abutment, using a digital torque wrench. The samples were covered with putty material to the abutment‒implant junction. Customized metal crowns with 45° inclinations were placed on the abutments and cyclic loading was performed accordingly. Thereafter, the secondary torque loss (STL) was measured. Microleakage test was also performed. Data were analyzed with Mann-Whitney and Wilcoxon tests (α=0.05).
    Results
    There were no statistically significant differences between the two phases of gamma counting between and within two groups (P>0.05). However, STL after cyclic loading was less than ITL in both groups (P=0.042).
    Conclusion
    Connection type and cyclic loading had no significant effect on microleakage. Furthermore, the internal con-nection had less TL as compared to the external connection. In addition, the STLs were less than ITLs in both groups.
    Keywords: Dental implant?abutment connection, leakage, gamma rays, torque
  • Feridoun Parnia , Javad Yazdani* , Parisa Fakour , Farhang Mahboub, Seyyed Mahdi Vahid Pakdel Pages 190-195
    Background
    Dental implants are utilized with an ever-increasing rate. One of the causes of abutment screw loosening has been identified as inadequate preload. The objective behind this study was to compare the maximum hand-generated torque for tightening abutment screws by professors and postgraduate dental students using a digital torquemeter with 0.1 N/cm precision.
    Methods
    In a laboratory study conducted in Dental Implant Department of Faculty of Dentistry, Tabriz University of Medical Sciences, the maximum hand-generated torque for tightening abutment screws by professors and postgraduate dental students was investigated, using a digital torquemeter with 0.1 N/cm precision.
    Results
    The participants consisted of 36 (41.9%) females and 50 (58.1%) males, totaling 86 participants, of whom 45 (46.87%) and 41 (53.13%) were university professors and postgraduate dental students, respectively. The mean age of the participants was 33.4±10.2 years with an age range of 25‒60 years; 50 (58.1%) participants were in the 25‒34-year, 23 (26.7%) in the 35‒47-year, and 13 (15.1%) in the 48‒60-year age range. The mean age of professors and postgraduate dental students was 41±8.3 and 25.1±3.3 years, respectively. The means of maximum torques generated by female and male professors were 14.3±3 and 20.8±4.2, respectively. The means of maximum torques generated by female and male postgraduate dental students were 14.7±3.4 and 18.7±4.3, respectively. Statistical analyses showed no significant differences between the mean maximum torques generated by professors and postgraduate dental students (P=0.051).
    Conclusion
    In the present study, the mean maximum torque generated by professors was higher than that generated by postgraduate dental students. However, the difference was not statistically significant. The mean maximum torque generated by male subjects was significantly higher. No interaction was seen between the studied groups and sex. However, there was a statistically significant difference between the mean maximum torques generated in different age ranges; i.e., the maximum torque generated in the 25‒34-year age range was lower than that in the other two age groups. Finally, the effect of age range on the mean maximum torque was similar in both groups.
    Keywords: Torque force, abutment screw, loosening
  • Ajita Rathi* , Prateeksha Chowdhry , Mamta Kaushik , Pallavi Reddy , Roshni , Neha Mehra Pages 196-200
    Background
    The present study was undertaken to evaluate the incidence of dentinal cracks during root canal preparation with different periodontal ligament simulating materials in vitro.
    Methods
    Seventy freshly extracted human mandibular first premolars were selected and divided into 7 groups in terms of simulating material: group 1: polyether impression material; group 2: polyvinyl acetate adhesive; group 3: polyvinyl siloxane impression material; group 4: cyanoacrylate adhesive; group 5: epoxy resin adhesive; group 6: positive control, without any periodontal ligament simulation; and group 7: negative control, where neither a periodontal ligament simulating material was used nor canal preparation was carried out. Root canal preparation was carried out in all the groups followed by sectioning of roots at 3 mm, 6 mm and 9 mm. The sections were evaluated under a stereomicroscope at ×2.5 for the presence or absence of cracks. Chi-squared test was used to compare the appearance of defective roots between the different experimental groups.
    Results
    The least number of cracks were found in the negative control group, followed by group 1 where polyether impres-sion material was used for periodontal ligament simulation. The difference was significant with a P-value of 0.002 for coronal sections.
    Conclusion
    Under the limitation of the present study, polyether and polyvinyl siloxane (light body) can both be used for simulation of periodontal ligament.
    Keywords: Periodontal ligament simulation, dentinal defects, stereomicroscope
  • S. Pushpa* , Chakit Maheshwari , Garima Maheshwari , N. Sridevi , Puneeta Duggal , Puneet Ahuja Pages 201-207
    Background
    The aim of this study was to evaluate the effect of acidic, neutral and alkaline environments on the solubility of white mineral trioxide aggregate (WMTA) and Biodentine (BD).
    Methods
    Thirty-nine ring molds were randomly divided into three groups of A, B, and C (n = 12) with pH values of 7.4, 4.4 and 10.4, respectively, and an empty mold was used as a control. Each group was further divided into two subgroups (1 and 2) according to the material studied. The samples in groups A, B and C were transferred into synthetic tissue fluid buffered at pH values of 7.4, 4.4 and 10.4, respectively, and kept in an incubator at 37°C with 100% humidity. Daily solubility at 1-, 2-, 5-, 14-, 21-, and 30-day intervals and cumulative solubility up to 5-, 14-, and 30-day intervals were calculated. Statistical analysis was carried out with independent-samples t-test, two-way ANOVA and post hoc Tukey tests using SPSS 18. Statistical significance was set at P<0.05.
    Results
    Both WMTA and BD exhibited the highest solubility in acidic pH with 5.4235±0.1834 and 10.7516±0.0639 mean cumulative solubility values at 30-day interval, respectively. At all exposure times, BD was significantly more soluble than WMTA (P<0.001).
    Conclusion
    Acidic periapical environment jeopardized the solubility of both WMTA and BD, affecting their sealing characteristics in clinical applications like perforation repair procedures and blunderbuss canals.
    Keywords: Biodentine, calcium silicate cements, endodontic inflammation, mineral trioxide aggregate, solubility
  • Mehmet Adiguzel* , Ipek Isken , Ismail Ilker Pamukcu Pages 208-212
    Background
    The aim of this study was to compare the cyclic fatigue resistance of XP-endo Shaper, HyFlex CM, FlexMaster and Race rotary instruments at body temperature (37±1°C).
    Methods
    Twenty XP-endo Shaper (#30/.01), 20 HyFlex CM (#30/.04), 20 FlexMaster (#30/.04) and 20 Race (#30/.04) instruments were tested at body temperature (n=20). The instruments were evaluated in artificial canals with a 3-mm radius of curvature and 60° angle of curvature to the center of the 1.5-mm-wide canal. Each instrument was rotated until fracture occurred and the number of cycles to failure (NCF) recorded. Data were analyzed using one-way ANOVA and Tukey HSD tests (P<0.05).
    Results
    The difference in the NCF of all the instruments was statistically significant (P<0.05). The order of the instruments from the highest to the lowest NCF was as follows: XP-endo Shaper (3064.0±248.1), HyFlex CM (1120.5±106.1), FlexMaster (569.8±48.4) and Race (445.5±53.5).
    Conclusion
    Under the limitations of the present study, XP-endo Shaper instruments were more resistant to cyclic fatigue than the #30/.04 nickel-titanium rotary instruments immersed in water at simulated body temperature.
    Keywords: Body temperature, cyclic fatigue, FlexMaster, HyFlex CM, Race, XP-endo Shaper
  • Matheus Felter* , Milena Moraes de Oliveira Lenza , Maurcio Guilherme Lenza , Wendel Minoro Muniz Shibazaki , Rhonan Ferreira Silva Pages 213-220
    Background
    Software programs for visualization and analysis of digital orthodontic models, apart from presenting the necessary features for diagnosis and treatment planning, also need to be user-friendly. This characteristic refers to software’ usability, a measure that evaluates how easy it is to use it is by a specific group of professionals. The aim of this study was to compare the usability of free available versions of two software programs for visualization and analysis of digital orthodontic models.
    Methods
    Digimodel® and OrthoCAD® usability were evaluated through their interface analysis and executing the following procedures: malocclusion classification and models analysis (arch-length and tooth-size discrepancies).
    Results
    Digimodel® and OrthoCAD® software programs had an installer only for Windows platform, occupied less than 110 megabytes of virtual space and only read files from their respective manufacturers. None possessed Portuguese as a language option. Both allowed visualization of the models in different axes through options present in initial screen, at a click. For model analysis, both software programs required to measure tooth to tooth and performed necessary calculations auto-matically. However, OrthoCAD® software program was less intuitive because the option for these actions was among several others, within menus, which could cause confusion during navigation. In addition, the marking of points did not always obey the clicked site.
    Conclusion
    The free access version of the evaluated software programs exhibited usability limitations related to language, supported file format and even the model analysis execution for orthodontic diagnosis. Although OrthoCAD® was inferior, both did not meet orthodontists’ clinical demand against these factors in the evaluated versions.
    Keywords: Dental models, dental technology, orthodontics
  • Majid Mehran , Gassem Ansari , Mojtaba Vahid Golpayegani , Shahnaz Shayeghi* , Leila Shafiei Pages 221-225
    Background
    The aim of this investigation was to compare the sedative effects of oral midazolam/chloral hydrate and mid-azolam/promethazine combinations on fearful children needing dental treatment.
    Methods
    This crossover double-blind clinical trial was conducted on 30 children aged 2‒6 years, who had at least two similar teeth needing pulp treatment. Standard vital signs were recorded before and after premedication. Wilson sedation scale was used to judge the level of sedation. Cases were divided into two groups based on the sequence of medication received. This was to overcome the sequence effect. Group I received oral midazolam (0.4 mg/kg/chloral hydrate (50 mg/kg) at the first visit while they received midazolam (0.4 mg/kg)/promethazine (5 mg/kg) in their second visit. Group II received the premed-ication in the opposite sequence. The operator and child were blinded to the medication administered. Sedative efficacy of the two combinations were assessed and judged by two independent pediatric dentists based on the Wilson scale. Data were analyzed with ANOVA and paired t-test.
    Results
    Only 10% of children who received chloral hydrate with midazolam exhibited high improvement in their behavior while 53% showed reasonable positive changes and 12% had no change or even deterioration of behavior. The difference between the effect of the two combination drugs was statistically significant (P<0.05) in favor of the chloral hydrate group.
    Conclusion
    The results showed a significant difference in the sedation level induced between the two groups. Midazo-lam/chloral hydrate combination more effectively improved the co-operation for dental treatment.
    Keywords: Child, chloral hydrate, dental sedation, midazolam, promethazine
  • K S Bharanija* _V Ashok _Anandapandian Ponsekar Abraham Pages 227-231
    The retention and comfort of wearing prosthesis mainly depends on saliva. In reduced saliva conditions, such as xerostomia or radiation therapy, the oral mucosa tends to become dry and ulcerated, leading to the patient's inability to retain the prosthe-sis. Various techniques have been reported in the literature regarding the use of a reservoir with holes in dentures. The results have not been satisfactory because the flow of the salivary substitute could not be controlled and with frequent cleaning of the denture being necassary to maintain the patency of the reservoir holes. A newer technique for incorporation of a palatal reservoir with controlled artificial salivary flow in complete denture is being explained in this article, which improved the denture retention, comfort, mastication and speech of the patient.
    Keywords: Artificial saliva, complete dentures, radiation-induced abnormality, xerostomia