Sara Abedini

Cryopreservation of periodontal ligament cells with magnetic field for tooth banking

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.

Gummy smile and facial profile correction using miniscrew anchorage.

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 patients teeth continued to be stable after a retention period of 36 months.

In-vitro and in-vivo study of periodontal ligament cryopreserved with a magnetic field

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.

Correction of severe open bite using miniscrew anchorage.

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 patients teeth continued to be stable after a retention period of 36 months.

Treatment of a Case of Skeletal Class II Malocclusion with Temporomandibular Joint Disorder Using Miniscrew Anchorage

Abstract 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 Schüller 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.

A newly developed snack effective for enhancing bone volume

BackgroundThe 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.MethodsOrchiectomy (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.ResultsAs 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.ConclusionIt 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.

A clinical survey for the association between root resorption incident to orthodontic treatment and host factors

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 resorption and host factors was statistically examined. Materials and methods: In this study, 243 subjects (72 male and 171 female subjects) were randomly selected from patients treated with multibracket appliances at the Orthodontic Department of Hiroshima University Hospital. The severity of root resorption was classified into five groups according to an index score from 0 to 4 defined by Malmgren et al., using pretreatment and post-treatment dental radiographs. Results: Root resorption was found in 78% patients, and prominent, in particular, in the upper and lower incisors and canines. The prevalence of severe root resorption was significantly higher in the teeth with short roots than in those with normal roots. The prevalence was also significantly higher in male than in female patients, and in patients with maxillary protrusion and age>20 years when active treatment was started. Moreover, teeth with trauma tended to exhibit a higher prevalence of root resorption than those without. Conclusions: Maxillomandibular incisors, teeth with short roots, male sex, maxillary protrusion, and age >20 years are risk factors for severe root resorption.

A case of bimaxillary protrusion treated with two-jaw surgery and genioplasty

A 22-year-old female patient visited our clinic with a chief complaint of antero-posterior direction. The maxillary incisors exhibited average labio-lingual inclination, and the mandibular incisors were labially inclined. The maxillary dental midline was shifted by 2.0 mm to the right from the facial midline. This patient was diagnosed as having bimaxillary protrusion and indicated for orthognathic surgery with presurgical and postsurgical orthodontic treatment. Prior to the operation, two mandibular first premolars were extracted and edgewise appliances placed on the maxillary and mandibular dentitions. The total presurgical treatment time was approximately 1 year. During surgery, two maxillary first premolars were extracted and maxillary anterior alveolar osteotomy was executed to move the dento-alveolar segment backward. Le Fort I osteotomy was preformed for the impaction of anterior and posterior segments, and the bones were fixed with titanium plates. Bilateral intraoral vertical ramus osteotomy (IVRO) was executed for counterclockwise rotation of the mandible, then advanced sliding genioplasty was performed along the mandibular plane. Postsurgical orthodontic treatment was continued for 23 months, and lingual bonded retainers and wraparound retainers were used for the retention. A remarkable improvement of gummy smile was achieved by Le Fort I osteotomy and IVRO with maxillary anterior alveolar osteotomy. Moreover, excellent lateral facial proportion was acquired by genioplasty. Orthognathic surgery provides harmony in occlusion and facial profile. DOI: 10.1016/j.odw.2010.11.013