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Background and objectives Micro-implant-assisted expanders have shown significant effects on the mid-face, including a degree of asymmetry. The aim of this study is to quantify the magnitude, parallelism, and asymmetry of this type of expansion in non-growing patients. Methods A retrospective study on a sample of 31 non-growing patients with an average age of 20.4 years old, with cone beam computed tomography images taken before and right after expansion using maxillary skeletal expander (MSE) were assessed for skeletal expansion at three landmarks bilaterally. Results Average magnitude of total expansion was 4.98 mm at the anterior nasal spine (ANS) and 4.77 mm at the posterior nasal spine (PNS) which showed statistical significance using a paired t test with p < 0.01. Average expansion at the PNS was 95% of that at the ANS. The sample was divided into symmetric (n = 15) and asymmetric (n = 16) based on the difference in expansion at the ANS, with 16 out of 31 patients exhibiting statistically significant asymmetry. Conclusions MSE achieves distinctly parallel expansion in the sagittal plane but can exhibit asymmetrical expansion in the transverse plane.

Background and Aim: Conversational repair skills are essential for establishing mutually successful verbal communication. Cognitive and linguistic disorders can have negative effects on these skills. Children with hearing loss have special cognitive and linguistic issues. This study was performed to contribute to the paucity of data on conversational repair strategies used by hearing impaired children. Methods: The participants included 58 children with moderate hearing loss (38 boys and 20 girls) aged 6 to 7 from Ahvaz city. A cross-sectional study design was used. Frequency of using different types of repair strategies in ten repair situations was calculated. Scores of intelligence, memory, word finding, lexical richness, and mean length of sentences was obtained through cognitive-linguistic tests. Data was analyzed employing an independent t-test, Pearson correlation coefficient, and logistic regression. Results: A direct correlation was observed between clarification strategy and communicative social intelligence (p=0.045). A direct correlation was observed between applying different types of conversational repair strategies and linguistic abilities in children with moderate hearing loss (p

This case report describes the treatment of a case involving a skeletal Class II facial profile with a gummy smile. While treating a facial profile and a gummy smile, the outcome may not always be successful with orthodontic therapy alone. For this reason, surgical therapy is often chosen to gain an esthetic facial profile and a good smile. However, sometimes the patients reject surgical treatment and an alternative method must be considered. Skeletal anchorage systems such as miniscrews are now frequently used for correcting severe malocclusion that should be treated by surgical therapy. In this case report, we treated a skeletal Class II malocclusion with a convex profile and a gummy smile using miniscrews, which were placed in the upper posterior and anterior areas. The active treatment period was 3.5 years, and the patient's teeth continued to be stable after a retention period of 36 months.

At the present time, there are no reports in the literature on the treatment of temporomandibular joint disorder (TMD) by intrusion of molars using mini-screws. This case report describes the treatment for a female patient, aged 19 years seven months, with a TMD and an excessive lower anterior facial height. Overjet and overbite were +5.0 mm and +0.5 mm, respectively. The patient had a history of orthodontic treatment in which her first premolars were all extracted. During the first orthodontic treatment, a clockwise mandibular rotation was observed as a result of the increase of posterior dentoalveolar height. She had temporomandibular joint (TMJ) pain during mouth opening and complained of difficulty in eating due to masticatory dysfunction. The pretreatment Schuller views of both TMJ showed a posterior condyle position. In order to correct the overjet, molar relationship and the mandibular condyle position, a miniscrew was inserted into the palatal region of the upper first molar to intrude the upper posterior teeth. As the upper molars were intruded, the overjet was decreased, and a class I molar relationship was achieved by a counterclockwise mandibular rotation. After one year of treatment, an acceptable occlusion was achieved, and the condyle moved into centric position in the glenoid fossa. The patient's teeth continued to be stable, and she had no pain in TMJ after a retention period of three years. The result of this treatment showed that molar intrusion using miniscrew anchorage is effective for treatment of a TMD patient with a posterior condyle position.

The purpose of this study was to establish a long-term tooth cryopreservation method that can be used for tooth autotransplantation. Human periodontal ligament (PDL) cells were frozen in 10% dimethyl sulfoxide (Me(2)SO) using a programmed freezer with a magnetic field. Cells were cryopreserved for 7 days at -150 degrees C. Immediately after thawing, the number of surviving cells was counted and the cells were cultured; cultured cells were examined after 48 h. Results indicated that a 0.01 mT of a magnetic field, a 15-min hold-time, and a plunging temperature of -30 degrees C led to the greatest survival rate of PDL cells. Based on these findings, whole teeth were cryopreserved under the same conditions for 1 year. The organ culture revealed that the PDL cells of cryopreserved tooth with a magnetic field could proliferate as much as a fresh tooth, although the cells did not appear in the cryopreserved tooth without a magnetic field. Histological examination and the transmission electron microscopic image of cryopreserved tooth with a magnetic field did not show any destruction of cryopreserved cells. In contrast, severe cell damage was seen in cells frozen without a magnetic field. These results indicated that a magnetic field programmed freezer is available for tooth cryopreservation.

This report describes the treatment of a case of severe open bite with posterior crossbite. While treating open bite, the outcome may not always be successful with orthodontic therapy alone. In such cases, surgical therapy is often chosen to gain a stable occlusion. Skeletal anchorage systems such as miniscrews are now frequently used for correcting severe malocclusion. In this report, we treated an open bite by intruding the molars with miniscrews placed bilaterally in the interdental space between both the upper and lower posterior teeth. The active treatment period was 36 months and the patient's teeth continued to be stable after a retention period of 36 months.

Aim The aim of this randomized, double blind clinical trial was to compare three lining materials (Adper Prompt L-Pop, VivaSens, and Copalite) versus unlined restorations on postoperative cold sensitivity of class I amalgam restorations. Methods and Materials Potential subjects were screened for the presence of four initial class I carious lesions on posterior teeth. Each tooth was assigned to treatments according to a randomized block design. After cavity preparation, teeth were lined with either VivaSens, Adper Prompt L-Pop, or Copalite, and one tooth remained unlined and served as a control. The cavities were filled with high copper amalgam (Oralloy). The time taken for a subject to respond to a standardized cold stimulus (CRM) was recorded at baseline, 24 hours, one week, and one month after treatment. Participants filled out a self-report questionnaire at each time point. Data was gathered by analysis of variance (ANOVA) and Duncan Multiple Comparisons tests (α=0.05). Results Twenty subjects participated in this study. Comparisons within each group found no significant reduction in mean CRM for the Adper Prompt L-Pop group (P>0.05), but a significant difference in mean CRM for the VivaSens group was observed at one week and one month intervals after restoration (P0.05). VivaSens showed more cold sensitivity than Adper Prompt L-Pop at one week and one month recalls (P Conclusion Adper Prompt L-Pop and Copalite reduced postoperative sensitivity to cold more than VivaSens and unlined groups at all assessment time points, 24 hours, one week, and one-month post treatment. The subjects receiving Copalite, VivaSens, and unlined restorations experienced greater sensitivity to cold at one month compared to baseline, while subjects receiving the Adper Prompt L-Pop liner experienced no greater sensitivity to cold from baseline to one month. Clinical Significance Adper Prompt L-Pop as a liner under spherical high copper amalgam successfully reduced cold postoperative sensitivity. Citation Hajizadeh H, Akbari M, Ghavamnasiri M, Abedini S. Clinical Evaluation of a Resin-based Desensitizing Agent and Self-etching Adhesive on Reduction of Postoperative Sensitivity of Amalgam Restorations. J Contemp Dent Pract 2008 November; (9)7:009-016.

Introduction The purpose of this study was to examine the effect of a new cryopreservation method with a magnetic field on periodontal regeneration in vitro and in vivo. Methods Human periodontal ligament cells were frozen in 10% dimethyl sulfoxide by using a programmed freezer with a magnetic field. Cells were cryopreserved for 3 days at −150°C. Immediately after thawing, collagen type I and alkaline phosphatase gene expression were determined by real-time polymerase chain reaction. Incisors were extracted from 15-week-old Wistar rats and cryopreserved or dried for 3 days. Then the incisors were replanted into the same sockets. Ninety days after transplantation, they were observed under light microscopy. Results There was no difference in the messenger RNA expression of collagen type I between the cryopreserved and the control groups. The expression of alkaline phosphatase messenger RNA in the cryopreserved group was slightly decreased compared with the control group. There was no progressive root resorption in the teeth that were replanted immediately (control group) or cryopreserved. However, there was widespread root resorption and ankylosis in the dried teeth. Conclusions These results show that a magnetic field programmed freezer can be successfully used for cryopreservation of teeth.

The purpose of this study was to evaluate the effects of long-term cryopreservation on the isolated human periodontal ligament cells (PDL) and pulp tissues. In the first part of study, 10 freshly extracted teeth were selected and divided into two groups. In the cryopreserved group, the teeth were frozen for 5 years using a programmed freezer combined with a magnetic field, known as Cells Alive System "CAS". As for the control group, freshly extracted teeth were used. In each group, extracted PDL tissues were cultured and gene expression and protein concentration of collagen type I, alkaline-phosphatase (ALP) and vascular endothelial growth factor (VEGF) was compared between the two groups. In the second part, pulp tissues were obtained from 10 mature and immature third molars which were freshly extracted or cryopreserved for three months. Expression of VEGF and nerve growth factor (NGF) mRNAs and the protein concentration in the supernatant were investigated. Results indicated that long-term cryopreservation with the use of CAS freezer cannot affect the growth rate and characteristics of PDL cells. There was no significant difference in VEGF expression and VEGF and NGF protein concentration of pulp cells derived from cryopreserved teeth with immature apex and control group with mature root formation. Finally, proper PDL regeneration and appropriate apexogenesis after transplanting magnetically cryopreserved immature tooth was clinically confirmed. These findings demonstrate that teeth banking with the use of magnetic field programmed freezer can be available for future autotransplantation as a treatment modality for replacing missing teeth.

Grid computing systems are a distributed geographical environment where the resources of entities are shared between each other and defining the type of entities is fully in control of their owners. Each entity can apply kind of limitations to the use of its resources by other entities. Because the resources of the non homogeneous grid belong to the various places with various business policies, it is very important and complex to manage the behavior trust of the resources in return to the requested works. In this paper a new method is proposed to the ability of probability theory for managing the behavior trust in grid computing systems.

Background The incidence of primary osteoporosis is higher in Japan than in USA and European countries. Recently, the importance of preventive medicine has been gradually recognized in the field of orthopaedic surgery with a concept that peak bone mass should be increased in childhood as much as possible for the prevention of osteoporosis. Under such background, we have developed a new bean snack with an aim to improve bone volume loss. In this study, we examined the effects of a newly developed snack on bone volume and density in osteoporosis model mice. Methods Orchiectomy (ORX) and ovariectomy (OVX) were performed for C57BL/6J mice of twelve-week-old (Jackson Laboratory, Bar Harbar, ME, USA) were used in this experiment. We prepared and given three types of powder diet e.g.: normal calcium diet (NCD, Ca: 0.9%, Clea Japan Co., Tokyo, Japan), low calcium diet (LCD, Ca: 0.63%, Clea Japan Co.,) and special diet (SCD, Ca: 0.9%). Eighteen weeks after surgery, all the animals were sacrified and prepared for histomorphometric analysis to quantify bone density and bone mineral content. Results As a result of histomorphometric examination, SCD was revealed to enhance bone volume irrespective of age and sex. The bone density was increased significantly in osteoporosis model mice fed the newly developmental snack as compared with the control mice. The bone mineral content was also enhanced significantly. These phenomena were revealed in both sexes. Conclusion It is shown that the newly developed bean snack is highly effective for the improvement of bone volume loss irrespective of sex. We demonstrated that newly developmental snack supplements may be a useful preventive measure for Japanese whose bone mineral density values are less than the ideal condition.

Vascular endothelial growth factor (VEGF) induces osteoclast differentiation as well as neovascularization by binding to the fms-like tyrosine kinase (Flt)-1 and fetal liver kinase (Flk)-1 receptors. The Flt-4 receptor also plays an important role in angiogenesis and lymphangiogenesis. The purpose of this study was to investigate the functions of Flt-4 in the signaling pathway of osteoclast differentiation. We examined the expression of Flt-4 on osteoclast precursor cells (OCPs), and the ability of recombinant human (rh) VEGF-D, one of the ligands of Flt-4, to stimulate the phosphorylation of extracellular-regulated kinase1/2 (ERK1/2) and to activate the nuclear factor-kappa B (NF-kappaB) pathway in OCPs. The number of osteoclasts induced by injection of rhVEGF-D in osteopetrotic (op/op) mice was also evaluated in the absence or presence of neutralizing antibodies to Flt-4. Flt-4 expression was detected on OCPs at both gene and protein levels and stimulation of Flt-4 by rhVEGF-D might induce activation of mitogen-activated protein kinase (MAPK) and NF-kappaB pathways for induction of osteoclast differentiation. Moreover, the number of osteoclasts in op/op mice increased after injection of rhVEGF-D, but was significantly reduced by the injection of Flt-4 neutralizing antibodies. We have therefore shown that Flt-4 expressed on OCPs, might activate MAPK and NF-kappaB pathways and played an important role in osteoclast differentiation.

The aim of this randomized, double blind clinical trial was to compare three lining materials (Adper Prompt L-Pop, VivaSens, and Copalite) versus unlined restorations on postoperative cold sensitivity of class I amalgam restorations.Potential subjects were screened for the presence of four initial class I carious lesions on posterior teeth. Each tooth was assigned to treatments according to a randomized block design. After cavity preparation, teeth were lined with either VivaSens, Adper Prompt L-Pop, or Copalite, and one tooth remained unlined and served as a control. The cavities were filled with high copper amalgam (Oralloy). The time taken for a subject to respond to a standardized cold stimulus (CRM) was recorded at baseline, 24 hours, one week, and one month after treatment. Participants filled out a self-report questionnaire at each time point. Data was gathered by analysis of variance (ANOVA) and Duncan Multiple Comparisons tests (alpha=0.05).Twenty subjects participated in this study. Comparisons within each group found no significant reduction in mean CRM for the Adper Prompt L-Pop group (P0.05), but a significant difference in mean CRM for the VivaSens group was observed at one week and one month intervals after restoration (P0.05). Copalite and the unlined groups showed significant mean CRM reductions after one day (P0.05). No significant differences between groups receiving Adper Prompt L-Pop and Copalite were found at any time point (P0.05). VivaSens showed more cold sensitivity than Adper Prompt L-Pop at one week and one month recalls (P0.05), while the most cold sensitivity was found in the unlined group.Adper Prompt L-Pop and Copalite reduced postoperative sensitivity to cold more than VivaSens and unlined groups at all assessment time points, 24 hours, one week, and one-month post treatment. The subjects receiving Copalite, VivaSens, and unlined restorations experienced greater sensitivity to cold at one month compared to baseline, while subjects receiving the Adper Prompt L-Pop liner experienced no greater sensitivity to cold from baseline to one month.Adper Prompt L-Pop as a liner under spherical high copper amalgam successfully reduced cold postoperative sensitivity.

The aim of this in vitro study was to evaluate the effect of 20% carbamide peroxide (CP) on the flexural strength (FS) of bovine enamel and dentin complex.One hundred sound bovine teeth were selected for use. Blocks (2 x 3 x 8 mm) from the middle portion of the facial surfaces of each crown were sectioned from the teeth. The specimens were randomly divided into five groups (n=20) based on the time period of vital bleaching. Group 1 comprised the control group kept in artificial saliva. The experimental groups subjected to immersion in 20% CP, Opalescence, for four, six and eight weeks, respectively (eight hours daily). Mechanical testing was performed 24 hours after the last treatment using an Instron Universal Testing Machine with a crosshead speed of 0.5 mm/min. The results were analyzed by one-way analysis of variance (ANOVA) and Tukey's test (a=0.05).Mean values for FS were 141.27, 103.06, 120.71, 130.23, and 117.90 (Mpa), respectively. Statistically significant differences in FS were noted among the groups. A statistically significant difference was observed between Group 2 (two week bleach) and the control.Application of 20% CP bleach for two weeks provided significant decreases in FS of bovine enamel and dentin complex. Similar decreases were not observed among the other groups.

Our recent studies showed that a programmed freezer with a magnetic field (CAS freezer) is helpful in the survival of periodontal ligament (PDL) cells after cryopreservation. The theory is that a magnetic field can prevent the cluster from growing by causing it to vibrate. In this letter, we commented in detail on the influence of a magnetic field during cryopreservation.

Introduction: The purpose of this study was to clarify the prevalence and degree of root resorption induced by force application during orthodontic treatment. Association between the root resorptio...