Autotransplantation: A biological treatment alternative for a patient after traumatic dental injury.

Traumatic dental injury is considered a public dental health problem because of a high childhood incidence, high treatment costs, and prolonged treatment time. Although management guidelines for traumatized teeth have been outlined, tooth loss following trauma is occasionally unavoidable. Here, we describe the successful interdisciplinary management of a traumatized central incisor in an 11-year old boy that was extracted because of a poor prognosis and restored by the autotransplantation of an immature donor tooth into the site. The patient underwent orthodontic treatment in order to close the donor site space and bring the autotransplanted tooth to an ideal position. Postorthodontic treatment radiographs and photographs revealed an esthetic and functional natural tooth replacing the lost tooth. The findings from this case suggest that autotransplantation offers unique advantages as a treatment modality for the restoration of missing teeth, particularly in growing children.

The effect of caffeine on orthodontic tooth movement in rats.

OBJECTIVES: to determine the effect of different doses of caffeine on orthodontic tooth movement (OTM) in rats. MATERIALS AND METHODS: Forty male 250-300 g Sprague-Dawley rats were randomly divided into four groups of ten animals each and received 0 (control), 1 g/l, 2 g/l and 3 g/l caffeine in tap water for 3 days. Orthodontic appliances were ligated between the maxillary first molars and incisors on the 4th day of the study period. All rats were sacrificed after 2 weeks of treatment after which OTM was measured. Hematoxylin/eosin-stained sections of the molars were prepared and the mesial roots were examined for resorption-lacunae depth and osteoclast number. ANOVA was used for statistical analysis (P<0.05). RESULTS: A significant decrease in OTM was observed only in the 2 g/l (P=0.043) and 3 g/l (P<0.01) caffeine-receiving rats compared to the control animals. Osteoclast counts and resorption-lacunae depths demonstrated significant differences between each of the caffeine groups and control rats (P<0.05). None of the variables showed significant differences between the caffeine groups (P>0.05). CONCLUSION: According to our findings, one of the effects of caffeine consumption during orthodontic treatment in rats was decreased root resorption. Additionally, concentrations of 2 g/l and 3 g/l inhibited OTM which seems to be due to its influence on osteoclast numbers.

Management of severely impacted mandibular canines and congenitally missing mandibular premolars with protraction of autotransplanted maxillary premolar.

Transmigrated mandibular canines increase the treatment complexity in terms of both anchorage and biomechanical planning. Additionally, a Class II malocclusion with a deep overbite and associated dental anomalies such as hypodontia can further increase the treatment complexity and the overall treatment time. This case report describes the successful interdisciplinary treatment of a patient, aged 12.5 years, with transmigrated and severely impacted mandibular canines and congenitally missing mandibular second premolars. The transmigrated mandibular right canine was extracted, and a maxillary second premolar was autotransplanted to the missing mandibular right second premolar site with the aid of a stereolithographic donor tooth replica fabricated with 3-dimensional cone-beam computed tomography and a rapid prototyping technique. Furthermore, the autotransplanted tooth was protracted by 4 to 5 mm to close the space caused by the extraction of the mandibular right canine. The impacted mandibular left canine was orthodontically guided into its normal position in the arch. Good esthetic outcome and functional occlusion were achieved.

The effect of celecoxib on orthodontic tooth movement and root resorption in rat.

OBJECTIVE: Inhibition of prostaglandin (PGs) production leads to decrease in orthodontic tooth movement (OTM). It is not known whether inhibition of cyclooxygenase-1 (COX-1) or cyclooxygenase-2 (COX-2) is the key mechanism for this effect. In this study, the effect of celecoxib, a highly-selective COX-2 inhibitor, was investigated on OTM in rats. MATERIALS AND METHODS: Four groups of male rats (seven animals in each goup) were used in the study. A 5mm-long nickel-titanium closed-coil spring was ligated between the right maxillary incisor and the first molar of each rat to deliver an initial force of 60g. All four groups recieved orthodontic appliances, group 1 received no injections, group 2 received celecoxib injections (0.3 mg in 0.1 ml saline solution), group 3 recieved normal saline injections (0.1 ml saline solution), and group 4 recieved needle penetration without injecting any solution. The local injections were carried out every 3 days for 18 days. All injections were subperiosteal and given in the upper right first molar mucosa. The animals were sacrificed 21 days after appliance insertion and OTM was measured. RESULTS: In the animals treated with celecoxib a statistically significant decrease in OTM was observed compared with the other groups. Histological findings revealed that osteoclast count was significantly lower in group 2 compared with the other groups (P<0.05). The amount of root resorption showed a slight, but nonsignificant decrease in group 3. CONCLUSION: This study suggests that celecoxib decreases OTM and osteoclast count. This might be the result of COX-2 enzyme inhibition and subsequent decrease in prostaglandin production.

The effect of fluoxetine on bone regeneration in rat calvarial bone defects.

OBJECTIVE: Fluoxetine is one of the most common medications used for the treatment of depression. Recent studies have demonstrated the possible effect of this drug on bone. The purpose of this study was to evaluate the effect of flouxetine on bone in Sprague-Dawley rats randomly divided into 3 groups (n = 7). STUDY DESIGN: Two calvarial defects, 5 mm diameter, were prepared in parietal bone. The left defects were filled with natural bovine bone mineral (NBBM) and the right defects were left untreated. The first group did not receive fluoxetine. The second group and the third group received 7.5 mg and 15 mg flouxetine, respectively, daily by gastric gavage. The animals were killed 8 weeks after surgery, and the amount of bone regeneration was evaluated using histometric analysis. RESULTS: The defects showed dose-dependent increase in bone formation. The bone fill length had statistical significant differences between NBBM/flouxetine (15 mg) group and other groups (P < .05). The presence of the NBBM had positive effect on the bone formation in all groups in so far as the maximum amount of the increasing effect was seen in those rats filled with NBBM that received 15 mg flouxetine (P < .05). The minimum bone length in fluoxetine-treated defects was seen in 7.5 mg defects (0.36 mm) CONCLUSION: Fluoxetine may improve the amount of bone regeneration in the rat calvarial defects.

Measurement of volume changes of sinus floor augmentation covered with buccal fat pad: a case series study.

OBJECTIVES: The purpose of this study was to evaluate the volumetric changes of the maxillary sinus graft in conjunction with buccal fat pad (BFP) covering the lateral sinus wall. STUDY DESIGN: In this article, the radiographic results are presented on 11 consecutively treated patients using an equal mixture of the autogenous bone harvested from the tuberosity and natural bone mineral (Bio-Oss) used to augment the maxillary sinus. Buccal fat pad was used over the lateral sinus wall in all cases as a membrane to cover the augmentation material. The mean initial bone height (IBH) was 3.82 mm as measured in the posterior maxilla. Three months after sinus elevation, radiographic evaluation was performed for the patients and secondary bone height was measured (SBH(1)). Fifty-two implants were placed in augmented sinuses. Prosthetic rehabilitation of the patients was done 4 months after inserting the implants. Radiographs were taken 6 months after implant placement and secondary bone height was measured (SBH(2)). RESULTS: Of 52 implants, 51 (98%) were considered clinically successful. One implant was removed because of mobility at the time of surgical exposure. Clinically, no complications were observed, and all implants were considered clinically osseointegrated after 6 months. Mean bone height was measured as 3.82 mm before sinus grafting. SBH(1) and SBH(2) were measured as 12.22 mm and 10.5 mm respectively. CONCLUSION: The clinical findings suggested that BFP might be a substitute for bioresorbable collagen membranes in maxillary and sinus floor bone grafts.

Effect of simvastatin administration on periodontitis-associated bone loss in ovariectomized rats.

BACKGROUND: Hydroxyl methylglutaryl-coenzyme A reductase inhibitors, so-called statins, have been widely used for hyperlipidemic patients. Recently, it has been reported that they promote bone formation. The purpose of this study was to evaluate the effect of simvastatin on ligature-induced bone resorption in the mandible of the ovariectomized rat. METHODS: Forty-nine rats were divided into seven groups; ligature was placed in all groups except group 7, which was considered the sham group: group 1 (N = 7), ovariectomy (OVX) plus simvastatin (10(-6) M); group 2 (N = 7), OVX plus simvastatin (3 x 10(-7) M); group 3 (N = 7), OVX plus simvastatin (10(-7) M); group 4 (N = 7), OVX plus normal saline; group 5 (N = 7), OVX group; group 6 (N = 7), ligature without OVX; and group 7 (N = 7), sham surgery without OVX and ligature. Simvastatin was administered subperiosteally in the buccal fold of the bottom right first molar twice a week during the study. Four weeks after insertion of the ligatures, the animals were sacrificed. Mandibles were removed for radiologic and histologic analysis. Bone density, bone loss (BL), and attachment loss were measured. Analysis of variance (ANOVA) was used to compare groups. RESULTS: Histologic analysis showed that the simvastatin groups developed significantly less periodontal breakdown (P <0.05). BL was less in the simvastatin experimental group, but there was not a significant statistical difference between the simvastatin groups (groups 1 through 3) and the experimental control groups (groups 5 and 6; P >0.05). CONCLUSION: Within the limits of this study, it can be concluded that simvastatin shows protective features against the impact of periodontitis on attachment apparatus and alveolar bone.

The effect of a constant electrical field on osseointegration after immediate implantation in dog mandibles: a preliminary study.

PURPOSE: The long time span between insertion of implants and functional rehabilitation often inconveniences patients. Accelerating bone growth around dental implants can shorten this time span. This in vivo study evaluated the effect of a constant electrical field on bone growth around dental implants. MATERIALS AND METHODS: Four mongrel dogs were used in this study. Sixteen dental implants were placed immediately after extraction of the first premolar and molar teeth. A constant electrical field (CEF) generator was placed in the mucoperiostal pouch created from the subperiostral dissection under the inferior border of the dog's mandible and connected to the experiment side fixtures. CEF provided 3 V of electrical potential during osseointegration. Histologic sections were stained with hematoxylin-eosin and observed under light microscopy. The sections were analyzed histomorphometrically to calculate the amount of newly formed bone. Statistical analysis was performed with SPSS 11.0 computer software (alpha= 0.05). RESULTS: At the end of the first stage of the osseointegration (90 days) CEF group sections showed enhanced growth of the trabeculae compared with the control group. Statistical analysis revealed significant differences between experimental and control groups. Bone contact ratio was statistically significant in the experimental group (p= 0.001). An increase in the local bone formation and bone contact ratio was observed with direct electrical stimulation of the implant and the bone area around the implant. CONCLUSION: Minimal direct electrical current, which can produce an electrical field around the implant, can increase the amount of bone formation and decrease the time of osseointegration.