مجله دندانپزشکی دانشگاه علوم پزشکی شیراز - Journal Of Dentistry
سال:1396 | دوره: | شماره: |تعداد مقالات:12

Oromandibular dystonia (OMD) is a rare focal neurological disorder that affects mouth, face, and jaws. This comprehensive literature review aimed to summarize the current evidence for etiology, diagnosis, and management of OMD and assess the possibility of dental origin of the disease and dental treatment plans for these patients.Different online databases namely PubMed, Google scholar, and Scopus were searched. The keywords "oromandibular dystonia", "orofaciomandibular dystonia", "orofacial buccal dystonia", "lingual dystonia", "jaw dystonia", "cranial dystonia", and "adult-onset facial dystonia" were searched in the title and abstract of publications from 1970 to 2016. The inclusion criterion was the dental etiology and/or dental treatment. Out of 1260 articles, only 37 articles met the inclusion criteria. OMD can be caused or exacerbated through different dental treatments within which anyone is likely to be involved due to various reasons. Some novel methods employed to relieve this syndrome have led to certain cure or improvement of symptoms in several cases. OMD patients may refer to dentists with involuntary jaw movements and intraoral presentations. Thus, the dentists should be aware of the symptoms and signs and refer the suspicious cases. Dentists should also be familiar with special considerations when managing OMD patients.

Statement of the Problem: The bond strength of composites with different adhesive systems with dentin is an important factor in long term durability of composite restora-tions. The effect of titanium tetrafluoride (TiF4) as anti caries agent and sodium hypo-chlorite (NaOCl) as disinfectant on the shear bond of nanofilled and silorane based composite resins have not been investigated in previous studies.Purpose: This study was conducted to determine bond strength between dentin and two composite systems, by means of shear bond test using TiF4 and NaOCl.Materials and Method: Middle dentin of 60 intact extracted maxillary premolar teeth were exposed by sectioning the crowns at a depth of 2mm from central groove and parallel to the occlusal surface. Standardized smear layer was created using a 600-grit silicon carbide paper and then samples were embedded in acrylic resin blocks. Then the samples were randomly divided into 6 \groups summarized as Group I: Z350, Group II: Z350+NaOCl, Group III: Z350+TiF4, Group IV: P90, Group V: P90+NaOCl, Group VI: P90+TiF4 according to manufacturer’s instruction. Then samples were subjected to shear bond strength (SBS) test using universal testing machine and data were analyzed using ANOVA and Tukey tests (p<0.05).Results: Application of 5% NaOCl caused a significant decrease in SBS of nanofilled composite resin (p=0.004), and also silorane based composite resin (p=0.006). Appli-cation of 4% TiF4 caused a significant increase in SBS of silorane based composite resin (p=0.001). The effect of TiF4 on nanofilled composite was not statistically sig-nificant.Conclusion: Using TiF4 has a positive effect on increasing the shear bond while NaOCl has negative effect on bond strength.

Statement of the Problem: Most of the soft tissue calcifications within the head and neck region might not be accompanied by clinical symptoms but may indicate some pathological conditions.Purpose: The aim of this research was to determine the prevalence of soft tissue calcifications in cone beam computed tomography (CBCT) images of mandibular region.Materials and Method: In this cross sectional study the CBCT images of 602 patients including 294 men and 308 women with mean age 41.38±15.18 years were evaluated regarding the presence, anatomical location; type (single or multiple) and size of soft tissue calcification in mandibular region. All CBCT images were acquired by New Tom VGi scanner. Odds ratio and chi-square tests were used for data analysis and p<0.05 was considered to be statistically significant.Results: 156 out of 602 patients had at least one soft tissue calcification in their mandibular region (25.9%. of studied population with mean age 51.7±18.03 years). Men showed significantly higher rate of soft tissue calcification than women (30.3% vs.21.8%). Soft tissue calcification was predominantly seen at posterior region of the mandible (88%) and most of them were single (60.7%). The prevalence of soft tissue calcification increased with age. Most of the detected soft tissue calcifications were smaller than 3mm (90%).Conclusion: Soft tissue calcifications in mandibular area were a relatively common finding especially in posterior region and more likely to happen in men and in older age group.

Statement of the Problem: Recently allogenic mesenchymal stem cells are proposed to have multipotential progenitor cell capabilities to differentiate into cementoblasts, osteoblasts, and periodontal ligament fibroblasts.Purpose: The aim of the present study was to compare the efficacy of human umbili-cal stem cells cultured on polylactic acid (PLA), polyglycolic acid (PGA) membrane with PLA/PGA membrane alone in the treatment of multiple gingival recession de-fects.Materials and Method: A total number of 14 cases of multiple gingival recession (Miller’s Class I or II) located in the anterior region were randomly selected and divid-ed into test (stem cells in combination with PLA/PGA membrane) and control group (PLA/PGA membrane alone). Clinical parameters including gingival recession, prob-ing pocket depth, clinical attachment level, and width of keratinized gingiva were rec-orded at baseline, and at 6 months postoperative.Results: At baseline, there was 2.28 mm and 2.14mm mean gingival recession at 16 sites and 14 sites in test and control groups respectively. At 6 months post-surgery, test group showed 1.57 mm mean reduction of gingival recession indicating 66% root coverage, while the control group showed 1.24mm mean reduction of gingival reces-sion indicating 57% root coverage.Conclusion: In the present study, the stem cell with PLA/PGA membrane showed significantly higher mean root coverage compared to only PLA/PGA membrane group.

Statement of the Problem: Dental caries in infants and young children is prevalent worldwide; its magnitude and associated factors vary between communities because of cultural and social economic differences. No such information was available for pre-school children in Mbeya city.Purpose: To determine dental caries status and associated factors in 2 to 4-year-old children in Mbeya city.Materials and Method: A cross sectional study was conducted among 525 children aged 2-4 years and their parents/caregivers. Caries was assessed using caries assessment spectrum and treatment index, oral hygiene by visual inspection for visible plaque on index teeth, and dietary and oral hygiene habits by a questionnaire. Kappa statistics was used to test reliability of study instruments, c2-test and logistic regression was employed for studying associations.Results: Caries free children for dmft1, dmft2 and dmft3 were 79.8%, 83.8% and 94.7% and caries experience was 0.49 (1.23), 0.4 (1.14) and 0.10 (0.53) respectively. Older age [(OR=2.722 (1.617-4.582) p=<0.001)]; and frequent consumption of factory made sugary foods/snacks at age 1-2 years [(OR=3.061 (1.188-7.887) p=0.021] were associated with caries. Prolonged breastfeeding for more than 1 year and breastfeeding at night had no association with dental caries.Conclusion: The prevalence of dental caries was very low. Older age and frequent consumption of factory made sugary foods at age 1-2 years were associated with higher odds of developing dental caries. Prolonged breas feeding and breastfeeding at night had no association with dental caries. Prevention of dental caries should be instituted as soon as primary teeth start erupting, especially through discouraging consumption of factory made sugary foods/snacks.

Statement of the Problem: Hearing impaired children have a problem in under-standing and comprehending with dental treatments. Visual language is the sensible answer of how to improve communication with them.Purpose: To evaluate the applicability of dental sign language in Hearing impaired children in relieving anxiety during stressful dental treatment by improving their means of communication.Materials and Method: This randomized clinical trial was carried out in the De-partment of Pedodontics and Preventive Dentistry which included 40 Hearing Im-paired children meeting inclusion criteria. The selected children were randomly divided into the study and control group comprising of 20 each. In the control group, initial oral examination and dental treatment (oral prophylaxis and class I restoration) were performed without the use of dental sign language. In the study group, the dental sign language specific to dental treatment was educated and dur-ing their subsequent visit to the dental clinic after dental sign language reinforcement, oral prophylaxis and class I restoration were done. Subjective and objective measurements of anxiety were recorded for both groups using facial im-age scale (FIS), pulse oximeter and electronic blood pressure apparatus to compare for correlation. The obtained data were subjected to statistical analysis using un-paired t-test.Results: There was a statistically significant reduction in the anxiety levels (p<0.05) in the study group compared to the control group.Conclusion: Dental sign language was effective in reducing the level of anxiety in children who are hard of hearing. Dental sign language was able to improve behav-ior positively during dental treatment and may also aid in developing a positive dental attitude among children who are hard of hearing.

Statement of the Problem: Root canal therapy should not simply be the extirpation of the pulp and widening of the canal. But one should also focus on how to completely remove the loosely-attached smear layer because it has adverse effects on the final outcome of the treatment.Purpose: This study compared the efficacy of Etidronic acid, SmearClear and MTAD to remove the smear layer created during instrumentation in different regions of the root canal.Materials and Method: Fifty single-rooted mandibular premolars were decoronated from the cementoenamel junction and instrumented using the ProTaper universal rota-ry file system along with copious irrigation by 1.0% sodium hypochlorite and distilled water. On the basis of the type of chelating agent used for irrigation, samples (n=10) were then randomized into five groups as: Group I- 9% etidronic acid, Group II- 18% etidronic acid, Group III- Smear Clear, Group IV- MTAD and Group V- normal saline. Subsequent to irrigation, all samples were rinsed, dried and sectioned longitudinally for evaluation of the smear layer removal under scanning electron microscope (2000X). Data were statistically analyzed by two-way analysis of variance and Tukey’s post hoc test with statistical significance set at p<0.5.Results: The result showed that Smear Clear was the most efficient in removing the smear layer. However, etidronic acid was found inferior than both Smear Clear and MTAD.Conclusion: Chelators are essential for complete smear layer removal in association with organic solvent.

Statement of the Problem: Use of traditional medicine to relieve human sufferings has a very long history. The effects of these plants in wound curing and subse-quently making the best mucosa patch for treatment of oral ulcers is still under investigation.Purpose: The main goal of present research work is to assess the efficacy of Myrtus communis L., Camellia sinensis L. and Zataria multiflora Boiss. on oral ulcer recov-ery process in rats.Materials and Method: In this study, 60 healthy adult male rats in 5 groups were investigated. A wound with 2 mm diameter was punched into the hard palate of each rat. For topical application, a mucosa patch of materials or blank was packed into the wound. Histological samples were harvested on post injury days 2, 4, 6, and 8.Results: This study showed that there were no significant differences between groups in the reduction of weight. Comparison of clinical wound size showed that group Myrtus communis L had the greatest reduction in wound size on days 4, 6 and 8, which was significantly different from the other groups. The highest thickness of epithelium was observed in groups Myrtus communis L and Camellia sinensis L on days 6 and 8. Group Myrtus communis L showed the highest values on days 6 and 8. This study showed a lower mononuclear cell counts in group Myrtus communis L on days 6 and 8 compared to other groups which was statistically significant.Conclusion: The results of the present study showed that Myrtus communis L. has significant effects on oral wound healing processes. These favorable results might introduce a new group of material or medicine derived from this plant.

Statement of the Problem: Evaluation of the color stability of materials used for the fabrication of the base of complete and partial removable dentures provides important information in relation to their clinical service. The color stability of nylon-based polymers as denture bases, compared to that of acrylic resins, has not been extensively evaluated since to date.Purpose: The aim of the present in vitro study was to evaluate the color stability of conventional polymethyl methacrylate and nylon-based polymer materials used for the fabrication of the base of complete and partial removable dentures.Materials and Method: Twenty samples were evaluated in the present in vitro study. One nylon-based polymer and one heat-cured acrylic resin were seleted for the purpose of the study. Ten disk samples, measuring 10 mm in diameter and 2 mm in thickness, were prepared from each material according to the manufacturers’ instructions. The samples were evaluted with the CIELAB sysem using spectrophtometery at baseline and after irradiation with UV light for 100 and 200 hours and thermocycling. One-way ANOVA and post hoc paired t-test were used to compare the color stability of the two groups. Statistical significance was set at p<0.05.Results: After 100 hours of irradiation with UV light and thermo cycling, color changes were tangible in both materials. After 200 hours of irradiation with UV light and thermo cycling, both materials exhibited a decrease in glaze. In general, chromatic changes in the acrylic resin were more noticeable.Conclusion: Accelerated aging affected the color stability of the acrylic resin and nylon-based polymer, p<0.05 for Da200 and Db200 and DL100; however, at the end of the study both materials exhibited clinically acceptable color stability (DE<3.7).

Statement of the Problem: Sinonasal papilloma (SNP) is a rare benign lesion characterized by high recurrence rate and malignant transformation.Purpose: This study aimed to investigate the prevalence of human papilloma virus (HPV) infection in these lesions in South of Iran.Materials and Method: In this cross sectional retrospective study, a total of 41 patients, 38 SNP and 3 SNP/Squamous cell carcinoma cases, from 2007 to 2014 were studied. Human papilloma virus (HPV) DNA detection was performed by nested PCR method and positive cases were analyzed for high risk HPV-16 and HPV-18.Results: HPV was detected in 31.7%; HPV- 16 in 4.9% and HPV 18 was not de-tected at all. Dysplastic epithelium was detected in 53% that was not associated with HPV. Three cases were accompanied with malignant transformation that HPV genome was detected in only one case and none of them were positive for HPV16 /18 genomic DNA.Conclusion: Current research suggests that HPV may be involved in the develop-ment of SNP. But the high risk HPV is not important in malignant transformation. More studies are needed to elucidate the possible etiologic mechanism between HPV, inverted papilloma, and squamous cell carcinoma.

Solitary fibrous tumor has a wide spectrum of histopathologic features and many tumors show similar microscopic features. This similarity poses diagnostic chal-lenges to the pathologists and immunohistochemical analysis is required in many cases. Moreover, it is a rare entity in orofacial region which consequently would make its diagnosis more challenging in oral cavity. The knowledge of various mi-croscopic patterns of this tumor contributes to a proper diagnosis and prevents unnecessary treatment. This study reports a case of solitary fibrous tumor in the retromolar pad area and discusses its various histological features and differential diagnoses.

Taurodontism is a relatively rare variance with a very low incidence in primary dentition and only a few cases have been reported in the literature. It stands a challenge when these teeth require pulp therapy. This case report illustrates the oral rehabilitation of multiple primary molars with taurodontism involving both the maxillary and mandibular arches, which is a rare occurrence.