Biomedical subjects

Behnam Eslami

Publications and source records attributed to Behnam Eslami.

6 recordsLinked to original sources

PubMed2006

The effects of loading time on osseointegration and new bone formation around dental implants: a histologic and histomorphometric study in dogs.

BACKGROUND: Immediate loading of dental implants has been introduced as a method of reducing implant treatment time without compromising its prognosis. In this research, the effects of loading time on the amount of bone-to-implant contact and bone formation around dental implants were evaluated histologically. METHODS: Three months prior to implantation, the lower premolar teeth of 15 dogs were extracted. Three or four dental implants were placed in the healed extraction sites for each dog (N = 48). Dividing the dogs into three groups, the implants were either loaded 48 hours or 1 week later with metallic or prefabricated acrylic crowns or were left unloaded until the time of sacrifice. Three months after implant insertion, the animals were sacrificed and samples were investigated to define the amount of bone-to-implant contact, lamellar and woven bone percentage, and local inflammation of the newly formed bone. RESULTS: No significant difference in the observed criteria was reported among the three groups (P >0.05); however, the unloaded group had the highest degree of bone-to-implant contact and the group loaded 48 hours after the primary implant insertion had the least. The prosthesis type had no significant effect on the implant success rate (P >0.05). The lamellar and woven bone percentage of newly formed bone also did not differ in the three groups (P >0.05). One implant from each group failed in this study. CONCLUSION: Loading time does not seem to significantly affect the degree of osseointegration and bone-to-implant contact and the composition of newly formed bone around dental implants.

Acrylic Resins↗

PubMed2005

A comparative study of white and grey mineral trioxide aggregate as pulp capping agents in dog's teeth.

Mineral trioxide aggregate (MTA) is widely used for different perforation repairs, root-end filling, pulp capping and many other endodontic procedures. Because of potential discoloration effect of gray MTA, white MTA has been introduced into endodontic treatment for the same purposes. This study examined the dental pulp responses in dogs to both types of MTA used as a pulp-capping agent. The pulps of 24 teeth of four male dogs were exposed with a No.1 round bur and capped with either gray or white MTA. Histologic analysis was performed one and 2 weeks after treatment. Calcified bridge could be seen 1 week after treatment with both types of MTA, with no significant differences between the two treatments.

Aluminum Compounds↗

PubMed2003

Histopathologic comparison of normal and hyperplastic condyles.

OBJECTIVE: The aim of this study was to compare normal and hyperplastic mandibular condyles using two different histopathologic staining techniques. STUDY DESIGN: Nine cases of condylar hyperplasia and 13 normal cases were studied after hematoxylin and eosin and silver staining. RESULTS: There was a significant difference between the two groups in the thickness of the hyperplastic cartilage layer of condylar soft tissue (P = 0.017). Also, the number of argyrophilic nucleolar organizer regions was significantly higher in the condylar hyperplasia case group (P = 0.0001). No significant differences could be demonstrated in cartilage island frequency, penetration depth, and distribution in the cancellous bone of condyles. CONCLUSION: The thickness of the hyperplastic cartilage layer appears significantly increased in condylar hyperplasia. In addition, argyrophilic nucleolar organizer region count may be useful in histopathological identification of condylar hyperplasia.

Adolescent↗

PubMed2003

A study of the relationship between ameloblastoma and human papilloma virus.

PURPOSE: The purpose of this study was to determine the relation of ameloblastoma with one of its probable etiologic factors, human papilloma virus (HPV). MATERIALS AND METHODS: This study was carried out in a retrospective, observational, and blind manner with information forms using an exact polymerize chain reaction. Fifty paraffinated blocks of ameloblastoma tumor were compared with 50 impacted third molar follicles. RESULTS: The results indicate that statistically the incidence of HPV positivity in the case group is significantly higher than that in the control group (P <.025). Furthermore, in determination of trace HPV type in HPV-positive samples, the incidence of type 6 HPV in the case group is significantly higher than that in the control group (P <.005). None of types 8, 11, 16, 18, 31, and 33 were observed. CONCLUSION: The results of this research conclude that HPV could be regarded as a possible etiologic factor of ameloblastoma.

Adolescent↗

PubMed2003

Nucleolar organizer regions in selected odontogenic lesions.

OBJECTIVE: The present study aimed to assess the usefulness of argyrophilic nucleolar organizer regions (AgNORs) as quantitative criteria in the diagnosis of odontogenic cysts and tumors. STUDY DESIGN: This descriptive cross-sectional study was done on archival paraffin blocks (n = 37), consisting of 10 conventional ameloblastomas, 7 cases of unicystic ameloblastoma, 10 odontogenic keratocysts, and 10 dentigerous cysts, all accessioned between 1994 and 2000. RESULTS: The findings showed a significant statistical difference among the 4 lesions (P <.001). Conventional and unicystic ameloblastomas had a significantly higher (P <.05) number of AgNORs than odontogenic keratocysts and dentigerous cysts. No significant differences were observed within each group of tumors or cysts. The number of AgNORs was also significantly higher (P <.005) in the nuclei of basal layer cells of the epithelial lining of keratocysts than in the nuclei of parabasal layer cells. AgNORs in conventional and unicystic ameloblastomas were smaller but more broadly distributed, which may indicate higher proliferative activity. CONCLUSION: AgNORs can be useful in the histopathologic differentiation of ameloblastomas from odontogenic cysts.

Ameloblastoma↗

PubMed2003

The effect of prostaglandin E2 and calcium gluconate on orthodontic tooth movement and root resorption in rats.

Possible modifications in orthodontic tooth movement (OTM) and root resorption as a result of local injections of prostaglandin E2 (PGE2) alone and with calcium gluconate (Ca) formed the aim of the present study. Twenty-four 8-week-old male Wistar rats were selected and randomly divided into three groups of eight. Both quadrants of the upper jaws of the first group of animals were used; therefore this group comprised two groups: control and normal. The upper left first molars of these eight animals were not placed under orthodontic force and received no injection, to serve as the normal group, considered for root resorption comparison only. The control group had localized submucosal injections of normal saline on the buccal side of the upper right first molar. In the third group, 0.1 ml of 1 mg/ml PGE2 was injected at the same site and the fourth group received an intraperitoneal injection of 200 mg/kg Ca (10%) in addition to the PGE2. All the injections were performed on days 0 and 7. The orthodontic appliance consisted of a closed coil spring ligated to the upper right first molar and incisor, exerting a force of 60 g during the 21-day experimental period, after which the animals were sacrificed. Palatal halves were removed for histological examination and for calculation of the amount of root resorption. Statistical analysis of data showed a significant (P < 0.05) acceleration in OTM after PGE2 injection compared with the control group. The addition of Ca reduced OTM but a significant increase (P< 0.05) was still recorded. A significant difference (P < 0.05) in root resorption was only observed between the PGE2 and normal groups. The findings show the importance of calcium ions working in association with PGE2 in stabilizing root resorption while significantly increasing OTM.

Analysis of Variance↗