Journal of Dental School
Year:2009 | Volume:27 | Issue:2 (80)|Papers Count:11

Background and Aim: The rare case of Incontinentia Pigmenti (IP) also known as Bloch-Sulzberger Syndrome was first introduced by Garrod (1906). This genetically condition involves the skin followed by the teeth. It is also known as a sex linked dominant trait. Brownish gray spots are routinely seen on abdominal and limber skin. The aim of this report is to illustrate the clinical feature of IP cases with reference to earlier reports.Case Report: An 8.5 year old girl was referred to the Pedodontic Department for her lack of teeth. Several missing teeth were noted in both jaws with only a number of teeth being present in mouth with change in form. Patient chief complaint was malfunction in mastication and esthetics. Present teeth in clinical exam were as follows: 51,52,61,62,72,73,83. Patient was available for a follow up appointment after 1.5 year. Both upper permanent central incisors were semi erupted at this stage along with newly erupted upper primary canines. Clinical consultation was obtained from departments of oral pathology, oral pediatrician medicine and medical genetics. The condition was agreed as Bloch-Selzberger Syndrome also named as Incontinentia Pigmenti.Conclusion: Based on the collected clinical evidences including the lack of several teeth Incontinentia Pigmenti was diagnosed in association to hyper pigmented spots on skin of abdominal sides. Preventive and intermediate dental treatments are encouraged in such cases.

Background and Aim: Using provisional luting agents in cemented type implant supported prosthesis have advantage of retrievability; however adequate retention is demanded. This study compared the retention of restoration cemented with different types of provisional luting agents.Materials & Methods: In this experimental study, thirty titanium implant abutments (Biohorizons) with 8mm height, were placed in implant analogs and torqued to 30 N/cm. Implant analogous were mounted in auto polymerizing acrylic resin blocks using surveyor. After casting crowns for each abutment, provisional luting agents TempBond, Dycal and TempBond NE were used to cement the restorations upon their respective abutments. All specimens were stored in 100% humidity for 48 hours at 37°C prior to testing. Each crown was pulled from the abutment with a 500 kg load in a universal testing machine at a crosshead speed of 0.5 cm/min, and tensile strength was recorded in Newton. Data were analyzed using ANOVA.Results: Tensile strength was significantly higher for Dycal (26.01±3.53) than for TempBond NE (22.00±3.06) and TempBond (15.60±2.67).Conclusion: When retrievability of implant supported prosthesis is desired, Temp Bond is suggested to be a better choice and Dycal when additional retention for prosthesis is required.

Background and Aim: Asthma is known as a probable risk factor for dental caries; however there is some controversy in this issue. Present study is designated to evaluate the caries status in asthmatics compared to non asthmatic controls. In addition probable factors and co-varieties associated with dental health were also investigated.Materials & Methods: Forty five asthmatics and 46 healthy controls aged 6 to 12, entered this case-control study. There was a history of asthmatic drugs for at least one year including inhalators of beta–agonist, Corticosteroid or both. DMFS Index recorded according to visual- tactile method. Stimulated saliva was obtained and microbial count performed as CFU/ml for S. Mutans and Lacto Bacilli. Data analysis performed according to t-test, Mann-Whitney, Kendall's Rank Correlation and Ridge Regression.Results: Mean DMFS Index was 3.98±2.53 in asthmatics and 4.3±2.81 in healthy controls. The difference was not significant caries. Final Ridge Regression showed significant correlation between drug regimen and caries (P=0.001, r=0.76). Those received beta agonist along with protective corticosteroid had significantly less caries compare to beta agonist alone (P<0.001). S. Mutans count revealed significantly higher in controls. Lactobacilli count was not significantly different.Conclusion: DMFS index was not significantly different. Inhaled corticosteroids in asthmatics leads to better control of disease process, and reduce dental caries maybe because of reduced beta 2-agonist consumption as a potent xerostomic.

Background and Aim: The purpose of this study is to examine the effect of administration of bisphosphonate; an antiosteoclastic agent i.e. Pamidronate, on the orthodontic tooth movement and root resorption in rats.Materials & Methods: The present experimental study was conducted on 30 male 8 weeks old Wistar rat. On day zero the orthodontic appliance was installed. Control group received normal saline and for experimental groups, Pamidronate 1mg/kg, was injected intraperitoneally. After 21 days, rats of control group and experimental were sacrificed and the upper jaws were dissected and the distance between upper 1st and 2nd molars were measured. Under light microscope root resorptive lacunae were calculated by computer software. Student t-test was used for purpose of comparison between groups.Results: There were significant differences between the control (0.562±0.168 mm) and the experimental group (0.346±0.197 mm) for orthodontic tooth movements (p<0.01 by paired t-test). Looking to root resorption no significant differences were observed between the control (0.25± 0.175×10-2 square millimeter) and the experimental group (0.26±0.125×10-2 square millimeter).Conclusion: According to the present study, Pamidronate can reduce tooth movement and at the same time no increase of the root resorption is observed.

Background and Aim: Autogenous bone grafts are commonly used for the reconstruction of bone defects in surgical procedures. The complication of preparing bone grafts and their application are important factors that have encouraged investigators to use human bone matrix gelatin human (BMG) which is one of the most popular graft materials. Because of the worldwide need for reconstruction of bone defects and its difficulty the aim of this study was to evaluate and compare the effects of BMG and auto graft on the reconstruction of bone defects in parietal bone of rats. Materials & Methods: In this experimental study, data was collected through microscopic observations. Human BMG produced using human Humorous bone based on Urist technical method. 12 healthy male Sprague dawley rats randomly assigned into 4 groups (3 rats in each group) and sacrificed in 7, 14, 24 and 60th days after surgery. Two defects were made in the left and right sides of parietal bone of all rats. Human BMG placed randomly in one side and auto graft in the other side and then all specimens in each group were assessed and compared histologically to each other. Assessments included amount, rate and type of bone formation, inflammation signs, fibrous tissue and cartilage formation to analyze the histologic findings, Wilcoxon-single rank test was used.Results: The results showed a reduction of inflammation and also increase in new bone formation in both groups during 7, 14, 24 and 60th day after surgery. Bone formation percentage in human BMG cases in 24th day was more than autograft. There was no significant difference between two groups in 60th day. Conclusion: The findings suggested that although human BMG has the same effects as autograft, the rate of reconstruction with human BMG is more.

Background and Aim: Size and form of teeth is not only important for aesthetic, but also should be in harmony with other parts of face. When there is no record before tooth loss, determination of proper tooth size is one of the most important step of treatment. The purpose of this study was to determine correlation ratio of mesiodistal widths of anterior teeth with craniofacial dimensions.Materials & Methods: In this cross-sectional study 100 cases (50 males & 50 females) were selected from dentistry students. Maximum frontal width, maximum bizygomatic width, bigonial width and cranial width were measured by face bow. Mesiodistal width of anterior teeth was measured by digital vernier. For analysis of data Pearson correlation and multiple regression tests were used.Results: Anterior Bolton ratio (78.76±2.8) was not significantly different from normal anterior Bolton ratio. Bizygomatic width and canine widths showed a significant relation (0.2-0.3) and also bigonial width and lower canine width had a significant relation (0.2-0.3). Proportions of bizygomatic width to upper centrals were 14.9 on right side and 14.7 on left side. A significant relation between upper and lower intercanine widths with bizygomatic and bigonial widths was found (p<0.05).Conclusion: Although there are different ways for prediction of tooth size, according to relation between some craniofacial and tooth widths, these craniofacial widths can be used for prediction of tooth size.

Background and Aim: In transferring relationship of jaws to opening axis of articulator by earbow earpiece of face bow is adapted on ear pin of articulator. So this study was done in order to compare position of earpiece representing external auditory meatus and ear pin of an articulator.Materials & Methods: This descriptive study was done on 30 students (15 males, 15 females, 20 to 25 years of age) with functionally acceptable occlusion. Kinematic center of rotation was located and maxillary cast was transferred to the Hanau articulator (Medular-196). In the next step, ear-bow is used to register orientation relation of maxilla and after positioning the fork on maxillary cast which was mounted in preview step, the position of center of earpiece of ear-bow was marked on graphs paper which were attached on two round aluminum plate positioned to condylar part of articulator. The last step was to compare registered points to ear pin position of articulator. Kolmogorov-Smirnov and t test were used to examine difference between genders and left and right sides at a significant level of P<0.5. Results: Positions of earpieces in 66.7% of the samples in the left part of the face and 70% in the right part were located upper; and more forward as the current ear pin of the condylar compartment. There were no significant differences between both sides and difference based on gender.Conclusion: Considering all achieved results in this study, the current locations of the ear pins in mentioned articulator are not suitable for our samples and some changes must be considered in mounting of casts.

Background and Aim: The use of bleaching agents for the sake of whitening teeth has extended for many years. On the other hand, due to the simultaneous presence of a series of tooth colored restorations and existence of few research studies on the effect of different whitening materials on the tooth restorations, the present study with the aim of determining the efficacy of carbamide peroxide on the hardness of Glass Ionomer cements had been emerged. Materials & Methods: Forty numbers of glass ionomer cylinders were prepared and preserved for 48 hours in 100% humidity and in the room temperature, then were divided into 4 groups each contained 10 samples. The bleaching gel 16% VARI-SHADE (Lochemco USA) was applied for groups I to IV as respectably o, 21, 42, 63 hours. Finally the microhardness of each sample group was measured by Vickers’s machine. Results: Microhardness mean was respectively 27.37±2.4, 25.98±2.7, 24.41±3.6 and 26.02±3.7 in group I to IV, and there was no significant difference between them.Conclusion: Vari-shade bleaching gel did not result to reduced microhardness of Vitremer glass-ionomer in the studied time.