Backgroud and Aim: microleakge is one of the most common cause of failure in restorative dentistry in this study the microleakge of filtek p90, filtek p60 was evaluated and compared. Materials and Methods: In this experimental study, on 48 premolar teeth standardized class II MOD preparations were made cervical margin of mesial preparation were 1mm above the CEJ and 1 mm and the distal preparation were 1 mm below the CEJ Samples divided in to 3 groups of sixteen teeth. A group: teeth were filled with filtek silorane (3M ESPE, USA) and silorane system adhesive self-etch primer and bond. B: teeth were filled with filtek silorane and Adper single bond plus. C: sixteen teeth were filled with filtek p60 and Adper single bond plus. After AgNO3 dye opplicaiton microleakage were evaluated by stereomicroscope. data were statistically analyzed by kurskal-wallis and Wilcoxon. the level of 0. 05 considered significant. Results: The most enamel microleakage was related to C and lowest enamel microleakge was shown in A group. The most dentin microleakage was related to B and the lowest dentin microleakge was shown in A group. Microleakage was significantly different between A, with B and C (P‹ 0. 05) dentin microleakage was not significant difference between B and C. Conclusion: Type of composite and bonding effect to microleakage, the lowest microleakage was gingival margine irrespective of the location of the margine related to group A.

The role of pharyngeal space has been debated on developing respiratory problems and craniofacial deformities for many years. The purpose of this investigation was to find any differences in oropharyngeal dimensions between skeletal class I and class If malocclusions.Eighty patients with class I malocclusion (40 in 9-13 year & 40 in 18-30 year-old age groups) were compared to sixty patients with class Il malocclusion due to mandibular deficiency (30 in 9-13 year & 30 in 18-30 year old age groups). Patients were selected from those who had no respiratory problems, facial asymmetry, aberrant growth pattern, parafunctional habits, TMJ diseases, vestibule-cochlear, visual & hearing disorders, hypertrophy of adenoids or tonsiles, previous orthodontic treatment or maxillofacial surgery.A lateral cephalogram in Natural Head Position was taken from every patient. Skeletal relationships of craniofacial structures and oropharyngeal dimensions were measured together with the soft palate. Hyoid bone and cervical column position Results indicated that:1- There was no difference in oropharyngeal dimensions, soft palate, hyoid hone and cervical vertehral column position between skeletal class I and class If malocclusions in the normal respiratory pattern.2- Oropharynx showed some degree of growth in vrtical dimension during the growth period whereas  its sagittal depth remained mostly stable, except in the upper and lower border al class I malocclusion (PNS-UPW: p<0.01, Spt-PSpt: P<0.03, Va-PVa: P<0.01).The hyoid bone showed down ward move while the posture of cervical column and facial growth had no change. Finally, Soft palate showed a significant increase in length (PNS-U: P<U.OI) at class I malocclusion.

Background & Aim: Sandwich technique with glass ionomer (GI) has been recommended to overcome gingival microleakage. The study objectives were to compare open and closed sandwich techniques and evaluate GI injection in sandwich RESTORATIONs.Materials & Methods: Sixty extracted sound premolar teeth were divided into 4 groups (n=15). A Class II cavity with gingival margin below CEJ was prepared on each tooth. Teeth were restored using glass ionomer (Fuji II LC), adhesive (Single Bond) and resin composite (Z250) as follows: Group 1, Open sandwich, GI injection; Group 2, Open sandwich, placing GI by a probe; Group 3, Closed sandwich, GI injection; Group 4, Closed sandwich technique, placing GI by a probe. Dye penetration was performed by using fushin after thermocycling. Teeth were sectioned then dye penetration was evaluated (0-3 scores) under a stereomicroscope. Statistical analysis was conducted using Kruskal Wallis and Mann-Whitney U tests. Results: The least microleakage was observed in closed sandwich technique with GI injection and the most microleakage was observed in open sandwich using GI by a probe. When comparing the handling techniques, it was shown that using a syringe was significantly better than using a probe (P<0.05). There was no statistical difference between open and closed sandwich techniques although the mean dye penetration happened less in closed technique. Conclusion: According to the results of this study, injection of GI into cavity is recommended because of better access and superior adaptation of GI with cavity walls.

Introduction: The purpose of orthognathic surgery is to correct facial deformity and dental malocclusion and to obtain normal orofacial function. However, there are controversies of whether orthognathic surgery might have any negative influence on temporomandibular joint. The purpose of this study was to evaluate the influence of orthognathic surgery on articular disc position and temporomandibular joint symptoms of skeletal CI II patients by means of Magnetic Resonance Imaging.Materials and Methods: Fifteen patients (10 women and 5 men) with skeletal CI II malocclusion, aged 19-32 years (mean 23 years), from the Isfahan Department of Maxillofacial surgery were studied. All received lefort I & bilateral sagittal split osteotomy (BSSO) and all patients received pre- and post surgical orthodontic treatment, Magnetic Resonance Imaging was performed 1 day preoperatively and 3 month post operatively. Statistical analysis of the positional change of the disk was done by Wilcoxon rank sum test.Results: The change of articular disc position after mandibular advancement surgery by means of sagittal split ramus osteotomy was not statistically significant, but it tended to be positioned anteriorly.Conclusion: It can be suggested that orthognathic surgery dose not significantly change the position of the articular disc.

Aim: This study was designed to determine any profile changes and indentify the role of the most significant factors responsible for these changes.Materials and Methods: Cephalograms of 56 class II Division I patients (36 female and 18 male with mean age of 10 years) were used to analysis any changes in the perioral soft tissue profile before and after the treatment. A correlation analysis and multiple regression analysis (forward) revealed complex interaction between dentition, bony structures and soft tissues of the perioral area.Results: Retraction at the upper lip and increase in lower lip length in boys were more predictable than that of others. Significant soft tissue changes occured in response to orthodontic treatment, Upper lip retraction was shown to be related to the following factors: a- Retraction of upper incisal edges during treatment, b-Retraction of Point A, c- Pretreatment upper sulcus thickness and d- Retraction of sulcus superior.Conclusion: A greater increase in lower lip length takes place with greater amount of maxillary incisa1 edge retraction during treatment and a greater amount of sulcus superior retraction.

Background and Aim: One of the most important factors in the treatment of C1 II Div I malocclusions by functional appliances is the clinical examination of patient profile after forward positioning of mandible. So determining morphological changes of chin, after functional therapy, plays an important role in the prediction of facial profile. The aim of this study was to evaluate the morphological changes of mandibular symphysis after treatment by Farmand (Fa2) functional appliance in C1 II Div I malocclusions.Materials and Methods: In this before-after clinical trial, based on a similar study, 18 female patients, aged 10-12 years, with C1 II Div I malocclusion were investigated. These samples were under treatment for 12 months. Some angular & linear variables and Ricketts analysis were used to evaluate changes in geometric position of chin. Nanda and Aki analysis were utilized to determine morphological changes of symphysis. Paired - t test was used to compare the amount of differences of mean value pre and post treatment.Results: The findings observed following therapy were as follows;1. Depth of symphysis was increased (P= 0.01).2. Lower anterior facial height increased significantly (p< 0.005).3. Facial angle increased during treatment (P= 0.04).4. Increase in the mandibular symphysis contour was significant that could be due to forward movement of pogonion point (P= 0.002).5. Forward and downward movement of symphysis was frequently observed among patients.Conclusion: Following treatment by (Fa2) functional appliance, correction of profile is not only because of forward growth of mandible but also the remodeling of anterior chin contour. This type of treatment leads to better results in patients with normal and or low facial height due to an increase in lower anterior facial height.

Background and Aims: One of the common human evolutionary anomalies is dental Missing. Evolution of dental system is toward deduction of teeth number. The Missing of third molar is interesting subject for dentists and genetic researches because of its variety in different races. Consideration of bilateral effect of third molar Missing with jaw relation is an important subject. The aim of this study was to evaluate the third molar missing in Cl I and Cl II skeletal (without rotation) and comparison of them together.Materials and Methods: The patients of the orthodontic department of school of Dentistry (Tehran University of Medical Sciences) were analyzed. About 121 patients had Cl I and 60 patients had ClI jaw relation. This relation identified based on cephalometric lateral radiographic ANB corner angle. Patient who had rotation in maxilla or mandible based on SN-Go Gn angle were excluded. The incidence of third molars agenesis in individual dentition quadrants, upper and lower jaw and right and left side of dentition was examined from panoramic radiography. AChi-square test was used for statistical analysis of data.Results: Missing of one or more third molar in skeletal Cl I and Cl II was 43% and 33.3%, respectively. Missing of one or more third molar in Cl II was fewer than Cl I, but no statistically significant differences were seen between them (P>0.05).Conclusion: There was not a direct relationship between jaw relation and third molar missing.