detection of early inter proximal caries: DIAGNOdent, conventional and digital radiography

Detection of caries in early stages is necessary for prevention and conservative treatment. The aim of this study was to evaluate the accuracy of laser fluorescence [LF] using DIAGNOdent pen and to compare it with conventional Bite -Wing [BW] and Digital Radiography [DR]. In this survey, eighty extracted molars and premolars were mounted in stone blocks to simulate contact points. Proximal surfaces of each tooth were examined with LF. The teeth were also diagnosed using BW and digital radiography. After these procedures, the teeth were histologically prepared and assessed for caries extension as the gold standard. Sensitivity, specificity, positive and negative predictive values and accuracy were calculated for each diagnostic system in comparison with the gold standard. Cut-off points were calculated with ROC analysis. Comparisons between the accuracy of methods were performed using McNemar test. At dentinal caries, LF had the highest sensitivity and specificity [0.82 and 0.84, respectively]. For detection of early inter proximal caries, the sensitivity of LF [0.74] and specificity of DR [0.95] were the highest. The LF positive predictive values were the least and negative predictive values were the most. There was no significant difference between conventional and digital radiography in the detection of interproximal caries. DIAGNOdent might be a useful additional tool in detecting early interproximal caries, but due to the false positive responses at decision making for restorative treatments, auxiliary methods should be used

Effect of 10% carbamide proxide on mercury release from two types of dental amalgam

The chemical reactions occur at the amalgam surface when exposed to bleaching agents. Mercury ion is released from dental amalgam when bleached. The aim of this in vitro study was to investigate the effect of carbamide peroxide [CP] on the release of mercury ion from two types of spherical dental amalgam. Two commercial brands of dental amalgam, Cinalux and GS-80, were selected. 18 amalgam discs o any brand were prepared in silicon moulds according to the manufacturer's instructions. After 60 minutes, the discs were removed and individually immersed in artificial salvia [AS] for 24 h at 37°C. Then, the discs of any amalgam were divided into two equal test group [A] and control group [B]. Each specimen in the test group was treated in eight-hour cycles with 10% of CP. The specimens of the control group was treated in similar cycles with AS. All of the solutions were taken for Hg ion release determination, using cold-vapor atomic absorption mercury analyzer system. The data were analyzed using General Linear Model followed by Repeated Measures ANOVA. The results indicated that the bleaching agent significantly caused more mercury ion to be released into the solutions [p<0.05] but artificial salvia did not show this effect. The release rate of mercury from the Cinalux during the two weeks of treatment period with 10% CP showed an increase from 11.63 micro g/lit in the first day to 228.85 micro g/lit in the last day. The release rate from GS-80 showed a decrease from 130.96 micro g/lit in the first day to 80.68 micro g/lit in the last day. Treatment with 10% carbamide peroxide increased mercury release from dental amalgam in comparison with the artificial salvia. The release of Hg from 2 brands of dental amalgam was in a safe range

[Comparison of face mask treatment with or without expansion screw in dentoskeletal changes of Class III patients]

Among various treatments available for patients with Class III malocclusion, orthopedic protraction of maxilla during the mixed dentition period has been reported to be beneficial in cases with maxillary deficiency. In such patients, however, the maxillary expansion is not sometimes needed. The aim of the present study was to evaluate the therapeutic effects of face mask with and without maxillary expansion screw in Class III malocclusion patients who had maxillary deficiency. Twenty children with class III malocclusion were selected and randomly divided into two equal groups [A and B]. The children in group A were treated with a protraction face mask, and patients in group B were treated with a face mask and removable slow maxillary expansion device. The cephalometric changes in maxilla and mandible, and alterations in dental relations were compared within and between groups before and after treatment. Before-after comparisons in each group were performed with paired sample t-test. Covariance analysis served for between groups comparisons. In group A, the overjet was improved and molar relation was changed into normal occlusion [Class I]. The cephalometric analysis in group B revealed that Class III malocclusion was modified through a forward movement of the maxilla and a backward rotation of the mandible. Face mask is a favorable treatment in improving the antero-posterior position of maxilla and mandible in Class III patients even if they don't need palatal expansion

Cephalometric evaluation of patients with Class III malocclusion after face mask therapy in mixed dentition period

Among different treatment options for patients with Class III malocclusion, orthopedic protraction of maxilla can be a beneficial treatment procedure during the mixed dentition period. The aim of this study was to evaluate the cephalometric changes of Class III patients in the mixed dentition period following face mask therapy without any maxillary expansion. This study was conducted to compare the pre and post treatment conditions of 10 children in mixed dentition period that had class III malocclusion and maxillary deficiency according to the Steiner and Mc Namara's analyses. These patients were treated with protraction face mask without any maxillary expansion. The cephalometric changes of maxilla, mandible, soft tissue and dental relationships during treatment were recorded and analyzed using Paired sample T test. Significant changes were found in several variables [P < 0.05]. The mean improvement in overjet was 2.3 mm, the N.Sn.Pog angle decreased 3.5 degrees and the soft tissue profile was improved greatly. A Class I molar relationship was also achieved. The ISA and ItoNA distances increased 2.8 and 2.3 mm respectively, resulting from anterior movement of maxillary incisors. Face mask therapy without maxillary expansion is able to improve the horizontal position of maxilla in Class III malocclusion during the mixed dentition period