Aims: Aim of the study is to evaluate some physical properties of locally prepared dental stone form natural gypsum by two different calcination methods with autoclave with and without adding crystal habit modifier during calcination procedure for different periods of time. Materials and methods: The values of some physical properties that include specific gravity, water/ powder ratio and linear setting expansion of the prepared dental stone with autoclave with and without adding crystal habit modifier during calcination procedure for different periods of time and compared with that of commercial den-tal stone. ANOVA and Duncan's multiple range test were performed to determine the significant differ-ence among the tested groups at p ≤ 0.05%. Results: Results showed that there were significant differ-ences of the values of the physical properties between the locally prepared dental stone with autoclave and the commercial one at p≤ 0.05 in specific gravity, water/ powder ratio and linear setting expansion. Conclusions :The results appeared the alpha- calcium sulfate hemihydrates dental stone that prepared in autoclave with adding crystal habit modifier has superior properties than of that prepared without modifier, but still not reach the properties of the commercial product. All values of the tested proper-ties were in accordance with ADA Specification

The aims of this in vitro study was to assess the effectiveness of various bur types and bonding agents on the shear bond strength of composite resin to dentin. Eighty non carious, extracted human molars were mounted in acrylic resin, the occlusal surface of all the teeth were grounded to obtain flat dentin surface. After that the teeth were randomly divided into four groups (n=20) according to the bur types that will be used to prepare the dentin surface. After preparation of dentin each group was divided into two subgroups (n=10) according to the type of adhesive systems used (Excite & I-Bond), the adhesive systems were applied to the dentin surface and light-cured according to manufacturers instructions. A 4mm high composite cylinder was incrementally built up. After that, specimens stored for one month at 37ºc in distilled water and thermo cycled for 500 cycles between (5ºc & 55ºc) and then tested in a universal testing machine. The results of this study demonstrated that the method of surface prepa-ration affected the shear bond strength of I-Bond and this is not true for Exit system, when the dentin surface prepared with fissure burs the shear bond strength greater than when the surface prepared with round burs. The results of this study also showed that the groups in which Excite bonding agent used have greater value of shear bond than the groups treated with I-Bond.

To evaluate the clinical effectiveness of ethanolic extract of propolis (viscous solution12.5%) compared with the effect of Acyclovir (ACV) cream 5% in patients with recurrent herpes labialis (RHL). Materials and Methods: Thirty patients with active lesions (intact vesicle and rupture lesions) were included in this clinical trial. Fifteen patients were treated with viscous solution of ethanolic propolis extract while the other fifteen patients were treated with Acyclovir cream 5%. Results: Com-plete resolution of prodromal symptoms ( itching, tingling or burning) and erythema were noticed in propolis group after two days of treatment compared with none in ACV group. Statistically very high-ly significant difference in RHL lesion size in ACV group was observed (P<0.000), compared with highly significant difference in propolis group (P < 0.001). Conclusions: ACV cream 5% appeared to be more effective topically in healing time than ethanolic extract of 12.5 % viscous solution of propo-lis.Topical propolis would alleviate symptoms and erythema of RHL completely after two days whe-reas this action was not seen in topical ACV cream 5%.

To aid the dentist in a more precise method for psychological and neurotic assessment of his patients, especially the edentulous; and to isolates those who may refuse the complete denture wearing for psychological reasons. Materials and methods: The study was conducted to include one hundred members, who agreed to participate in it. They were collected randomly from Dental College of Mosul University, and a Dental Health Center at Mosul City. Members were asked to answer these question-naires: Eysenck Personality Inventory; Hamilton Anxiety Scale; and Mental Health Questionnaires. Statistical analysis of questioner was done according to percentage, and prevalence . Results: The data collected from these scales undergone statistical and correlation analysis to show the frequency and prevalence for each question and the most effectible components to introduce new psychological case–sheet, briefed what most important psychological factors that could investigated by the dentist. Conclusions: A modified psychological scale was accomplished for edentulous patients. The results also revealed that the general somatic sensory symptoms, autonomic nervous symptoms, insomnia and gastro–intestinal symptoms; represented the most effective factors on the stress development, especially in the geriatrics

Aim: To determine the prevalence of white spot lesions in orthodontic patients treated with fixed or-thodontic appliances at different treatment periods and to reveal the teeth most commonly affected by white spot lesions. Materials and Methods: Forty eight patients (31 females and 17 males) treated with fixed orthodontic appliance were included in this study. The patients were examined for the pres-ence of white spot before insertion of the appliance and after its removal using visual examination. Results: This study showed that there was a significant increase in the formation of white spot lesions along with the increase in treatment duration in male group, while females showed no significant dif-ference in white spots at different durations. The first molars were the most affected teeth by white spots followed by canines and second premolars. Conclusion: This clinical study showed that the teeth in buccal segment were affected by white spots more than incisors and the prevalence of white spots increased when the duration of treatment increased.

The aim of this study was to investigate the effect of storage time (immediately after polymerization and after one month of artificial saliva storage) on the degree of conversion (DC) of restorative type of light cured dental materials. Materials and Methods: Sixty samples of polyethylene molds were prepared. The samples were divided into three groups each of 20. The first group was filled with Composite resin, second group was filled with Compomer and the third group was filled with Resin modified glass ionomer cement (RMGIC). Each group was subdivided into two subgroups; each of ten according to storage time: The DC was tested for the first subgroup immediately after polymerization, while the DC of the second subgroup was tested after one month of storage in artificial saliva. The DC was investigated by Fourier-transform infrared spectroscopy (FTIR). Results: ANOVA test was used for statistical analysis. The results showed that there was a significant difference (p<0.05) in DC between the subgroups tested immediately after polymerization and the subgroups tested after one month of artificial saliva storage for Composite resin and Compomer. While RMGIC showed no significant difference (p>0.05) in DC between the subgroup tested immediately after polymerization and the subgroups tested after one month of artificial saliva storage. Conclusions: One month storage time has an effect on the DC of Composite and Compomer, but it has no effect on the DC of RMGIC.

Aim of Study: This in vitro study was conducted to evaluate the shear bond strength of intra oral por-celain repair system using 10% sodium hypochlorite and different acid etch. Materials and methods: Forty specimens were prepared in form of metal disks (8mm in diameter, 15mm height) and porcelain was applied according to the manufacturer instructions.The specimens randomly divided into 4 equal groups. In Group I ,II the samples were treated with 9% hydrofluoric acid for one minute. While groups III, IV were treated with 37% phosphoric acid for one minute, after washing the specimens with water and dryness, groups II, III the surfaces treated with 10%sodium hypochlorite for one minute while group I and IV leaved untreated. After that, the surfaces of all samples were washed and dried and silane coupling agent (MonoBond-S Vivadent, Liechtenstein) was applied according to the manu-facturer instructions, then bonding agent (Excite) (Vivadent, Liechtenstein) and composite (tetric N–ceram) (Vivadent, Liechtenstein) were applied according to the manufacturer instructions. All the sam-ples were stored in normal physiological saline for 7 days. Then the samples were thermocycled ma-nually between two water baths After that Shear bond strength was tested using universal testing ma-chine. Results: using ANOVA and Duncan’s multiple range tests. The result showed that there was highly significant difference between groups treated with 10%sodium hypochlorite with untreated one. There was significant difference between samples acid etched using hydrofluoric acid with those etched with phosphoric acid. Conclusions: Sodium hypochlorite and hydrofluoric acid significantly increase the shear bond strength between composite resin and porcelain fused to metal specimens

Aims: To evaluat the microleakage of four types of soft Liners materials(Vertex, Molloplast B, Bony plus and Silicon promedica) with different surface treatment: acetone, monomer, and laser at different period of storage to highly impact acrylic resin. Materials and Methods: Two hundred and forty spe-cimens for microleakage have been prepared , each specimens consists of two parts: acrylic resin den-ture base part (30mm) diameter , ( 2mm) thickness of acrylic resin and (30mm) diameter, (2mm) thik-ness of soft liners. Soft denture liners bonded to three different groups of surface treatment: acetone, monomer, laser treated to denture base resin. Microleakage specimens underwent three aging proce-dures: storage at one week, one month without thermocyling and one month with thermocyling inside 2% methylen blue dye in 600 cycles. Results: The results showed that microleakage of Vertex and Molloplast_B in one week and in one month without thermocyling were the lowest value from the oth-er types , in one month with thermocyling the vertex was the lowest of microleakage than oth-ers.Treating the surface of denture bases with acetone and monomer had the highest value of microlea-kage from other types of surface treatment in one week ,while in one month without thermocyling and one month with thermocycle, there were no significant difference in microleakage among the the dif-ferent types of surface treatment of acrylic resin Conclusions: Permanent soft liner of acrylic type (ver-tex) had the lowest values of microleakage after different periods of storage and thermocyling .

Aims: To evaluate the effect of chlorhexidine digluconate rinsing solution on plaque and gingival bleeding in orthodontic patients with fixed appliances. Materials and Methods: This study included 42 orthodontic patients (29 females and 13 males), who were undergoing treatment in orthodontic postgraduate clinic of the collage of Dentistry, Mosul University. The patients of this study had a mean age of 18 years (range 12-28 years). The patients were divided in to control group (brushing only, N=20) and an experimental group (brushing +chlorhexidine digluconate mouth rinse, N=22). Plaque, gingival indices scores, in addition to pocket depth were measured in different three time periods (day 0, two weeks and four weeks). Results: Plaque, gingival indices scores, in addition to pocket depth shows statically significant differences at level (p≤0.05) among different genders between the two groups for each of the three time periods. Conclusions: The use of chlorhexidine digluconate based mouth rinses reduced bacterial plaque accumulation, pocket depth and improved the gingival index. Key wards: Chlorhexidine, Fixed appliance, Plaque, Gingivitis. Al-Sayagh GhDh, Mohammed RJ, Al-Shahery WGh. Effectiveness of Chlorhexidine Digluconate Mouth Rinse in Improving Oral Health in Orthodontic Patients with Fixed Appliances. Al-Rafidain Dent J. 2013; 13(1): 162-169.

Aims: To measure the linear shrinkage of composite resin by digital image analysis, to evaluate the effect of light curing type on composite resin linear shrinkage, to evaluate the effect of light curing intensity on linear shrinkage of composite resin and to evaluate the linear shrinkage of composite resin after 24 hours. Materials and method: images of composite samples were obtained before curing. The samples were cured with four types of light curing units, halogen light curing unit 420 mW/cm2, LED light curing unit 420 mW/cm2, halogen light curing 300 mW/cm2 and LED light curing unit 300 mW/cm2. the curing time was 40 seconds. After curing, the cured composite surface was exposed to the microscope allowing the attached camera to capture an image. The samples were then stored in 37 degree centigrade incubator for 24 hours and another image for each sample, was obtained. The images were analyzed via specially prepared image analysis program and the linear shrinkage was measured. Results: Regarding the type of LCUs, statistical analysis showed that composite samples cured with QTH LCUs exhibit significantly higher linear shrinkage values than those cured with LED LCUs. While regarding the intensity of the curing light, it was shown that LCUs with higher curing light in-tensities produce a significant higher values of linear shrinkage. Conclusion: The type and the intensity of the light curing unit play a major role in the end result linear shrinkage of the cured composite resin. Image analysis system is an excellent method to determine linear shrinkage.