فهرست مطالب رضا شاه اکبری

The present study aimed to evaluate the rate ofminiplate and miniscrew removal and its etiology after orthognathic surgery during 2016-2018. Materials &

For the purposes of this cross-sectional study, all the patients who referred to the surgical department of Dental School of Mashhad University of Medical Sciences, for orthognathic surgery were included. All cases were assessed to determine whether the miniplate and miniscrew were removed after the surgery or not. Subsequently, the age, gender, cause of removal, and type of their orthognathic surgery were identified. Finally, the collected data were analyzed in SPSS software (version 21).

The present study was performed on 69 subjects with the average age of 24.9±4.09 who underwent orthognathic surgery during 2016-2018. The aim was to analyze the miniplate and miniscrew removal and related variables. Based on the results, the rate of miniplate and miniscrew removal was 10.14% (7 cases out of 69 patients). It was found that infection and plate exposure were the most common reasons for miniplate and miniscrew removal after orthognathic surgery. Moreover, miniplate and miniscrew removal was more frequent in the mandible, compared to the maxilla. Furthermore, the removal had a significant relationship with the type of jaw movement and usage of alcoholic drinks (P<0.05).

Regarding the low rate of miniplate removal after orthognathic surgery (10.14%), it can be concluded that there is no need to remove asymptomatic titanium miniplates. It is only necessary to do so when there are indications and clear symptoms for the removal.

  The mandibular and maxillary third molars are one of the most prevalent impacted teeth. Third molars grow last and it is probable that they face space insufficiency which leads to their impaction. Impacted third molar should be removed from oral cavity surgically due to various side effects which are periodontal problems of second molar and the possibility of root resorption, tumors and cysts, weakness of mandible bone, idiopathic pains. Hence, they should be surgically removed which diminishes further risks. However, the operation may lead to periodontal problems of adjacent second molar tooth and periodontal pocket. The aim of the present study was to evaluate the effect of maxillary third molar removal on the periodontal condition of second molar. 30 patients who were undergoing oral surgery (Third molar extraction) in the Clinic of Dentistry, Mashhad University of Medical Sciences (Iran) in age group of 22 to 26 years enrolled in this study. Pocket depth, attachment loss, plaque index, bleeding on probing were evaluated in middistal, distobuccal, and distolingual sides of second molars pre and 6 months post operation. The pocket depth (P=0.187) and attachment loss (P=0.532) were insignificantly increased in two times (pre operation and 6 months post operation). Plaque (P<0.001), gingival index (P=0.006), and bleeding on probing (P=0.008) were significantly decreased in during time (plaque index=P<0.001). The results indicated that maxillary third molar operation does not negatively affect the periodontal tissues of second molar and this operation does not have any effect on life teeth

With the advancement of the instruments for oral surgeries, use of alternative methods instead of traditional scalpels has been evaluated, The present study aimed to compare the complications associated with electrosurgery techniques and use of scalpel during and after orthognathic surgery.
In this split-mouth designed study, 20 patient who were candidate for orthognathic surgery were enrolled. Symmetrical incisions were made using electrosurgical methods on one side of the jaw and routine techniques with a scalpel number 15 on the other side. Evaluation of the techniques was performed during the surgery and six weeks postoperatively based on specific parameters, including the cutting time, and rate of scar tissue formation. Finally, the collected data from the implications of the two methods were compared using Man-Whitney U- test.
Mean cutting time was 6.63±1.22 and 10.19±1.95 minutes in the electrical cautery and scalpel groups, respectively, which denoted a significant difference between the groups (P According to the results, cautery could lead to a more significant reduction in the cutting time compared to use of scalpel. Furthermore, the scar tissue produced in the electrocautery technique was significantly higher compared to scalpel, which could be due to the induced heat damage to the adjacent tissues.

One of the best methods for reconstruction of bone defects in the area of dental patients is using autogenously bone grafts that is considered the gold standard for bone defect augmentation. Different intraoral donor sites to harvest the bone graft are available and the maxillary tuberosity due to its convenient surgical access and fewer complications is a perfect place for taking a limited amount of bone. The aim of this study was to evaluate maxillary second molar periodontal problems after tuberosity bone graft harvesting. 15 patients admitted to the Department of Oral and Maxillofacial surgery at Mashhad Dental School with ages ranging from 20 to 40 years, were studied. For each patient, pocket depth index, gingival attachment loss index, plaque index, gingival index and bleeding on probing at four areas including middistal, disto buccal, disto lingual of each tooth, both before and 6 months after surgery were measured and recorded. Paired t test and Wilcoxon and Mc Nemar tests were used for data analysis (α=0.05). The data showed that the mean pocket depth of distal of maxillary second molar, both before and 6 months after surgery, showed a rate of 15.4% reduction which was significant (P=0.002). Plaque index, gingival attachment loss index and gingival index were ordinal evaluated as and all three had declined significantly over time (P-value=0.002, 0.025 and 0.077 respectively. Bleeding rate observed at 6 months after surgery showed a 21.4% decrease which was not significant (P=0.250). The removal of bone from the maxillary tuberosity, will not cause any periodontal problems for second molar maxillary and if the supporting bone distal to it is damaged during surgery, would be restored so that there will be a normal biologic width and pocket depth.

Mandibular symphysis and parasymphysis fractures are common fractures following mandibular trauma. The success of open or closed reduction treatment depends on the type of fracture, the experience of the surgeon, the facilities available, and the medical conditions of the patient. Each treatment has its own complications. The purpose of this study was to examine the side effects and the complications following open reduction treatment in mandibular symphsis and parasymphysis fractures. In this retrospective study, conducted at Shahid Kamyab Educational-Treatment Center in Mashhad, 208 patients suffering from symphysis and parasymphysis fracture who had undergone treatment with internal fixation were studied. The patients were also subjected to a follow-up period of 8 weeks and the subsequent complications from their treatment were recorded. Chi-square and Fisher’s Exact tests were used for statistical analysis (α=0.05). The results of study showed that the complications arising from open reduction treatment in mandibular symphysis fracture were at an acceptable level and the risk of complications was reduced if treatment started not later than ten days after fracture. In order to reduce the risk of complications after open reduction treatment in mandibular fracture, the open reduction surgery should be started as soon as possible.

Multiple supernumerary teeth are a rare phenomenon. It occurs more often in patients with syndromes such as Gardner''s syndrome، cleidocranial dysplasia and so on. This phenomenon in absence of such syndromes is rare. The purpose of this report was to introduce a case of non-syndromic multiple supernumerary impacted teeth. Case Report: A 29-year-old woman with no skeletal، metabolic، systemic and mental disorder was referred to oral and maxillofacial department of Mashhad dental school. In clinical evaluation، seven Permanent teeth were missing. In radiographic evaluation، there were a total of 15 impacted teeth which 7 of them were supernumerary. Missing or Excess of one or more teeth usually leads to occlusal and functional problems. In these cases، a complete clinical and radiographic examination accompanieal by a precise history should be performed to plan a suitable surgical-orthodontic-prosthetic treatment.

Contemporary cephalometric analysis in orthodontics is based on comparison between craniofacial portions and reference planes. One of these planes is Frankfort Horizontal (FH) Plane that can be made by anatomic portion or machine portion. The aim of this study was to determine and compare the angle between Anatomic Frankfort Horizontal plane (AFH) and True Horizontal (TH) with the angle formed by Machine Frankfort Horizontal plane (MFH) and TH. In this Analytical-descriptive study، digital lateral cephalograms were taken in Natural Head Position from 50 orthodontic patients with the minimum age of 14 and class I malocclusion (Viazis analysis on Onyx Ceph software was employed to confirm the class I malocclusion). Then on each cephalogram، two FH planes were constructed using machine and anatomic portions. Then the angle between each FH plane and TH plane was measured and recorded. Finally، the data were analyzed by paired t-test (=0. 05). Machine Frankfort Horizontal plane (MFH) and Anatomic Frankfort Horizontal plane (AFH) showed significant differences of -5. 66 and -1. 58 degrees with True Horizontal plane (TH) respectively (P<0. 001). For cephalometric evaluation in orthodontic patients if the Frankfurt plane be used، it is better to use anatomical portion، because the difference between the Anatomic Frankfort Horizontal plane (AFH) and True Horizontal plane (TH) is significantly less than the difference between the Machine Frankfort Horizontal plane (MFH) and True Horizontal plane (TH).

Lateral ridge augmentations are traditionally performed using autogenous bone grafts. However, the bone harvesting procedure, whether intra orally or extra orally, is accompanied by patient morbidity. So, applying bone substitute has been suggested. The aim of the present study was to compare the stability of implants in ridges augmented with mineralized cortical cancellous allograft blocks with implants in native bone using Resonance Frequency Analysis.

In this clinical trial study, approved by ethical committee of Mashhad university of Medical Sciences, nine subjects with insufficient ridge width were selected. Their ridges were augmented with mineralized cortical cancellous allograft blocks. After 6 months, implants were inserted. In control group, 9 subjects with sufficient ridge width were selected. Implants were inserted in the same place as the test group. ISQ was used for measurement of implants stability on third and sixth month after implants placement. Data were analyzed by paired and two sample t tests using SPSS version 15 software.

During the study period, two implants in allograft group failed. In the test group, the difference between mean ISQ at third and sixth month was statistically significant (P=0.008), but in the control group, it was not significant (P=0.065). At third month, the mean ISQ between 2 groups was not statistically significant (P=0.317), but at sixth month, the mean ISQ in control group was significantly higher than the test group (P=0.000).

The mean ISQ in both groups were enough to load the implants. This means that mineralized cortical cancellous blocks could be used as a scaffold for growth of the bone and ridge augmentation for implant placement.