Healing of dentate or edentulous mandibular fractures treated with rigid or semirigid plate fixation — an experimental study in dogs

Lucas

Int J Experimental Path

et al. 2008

The objective of this study was to evaluate the bone repair along a mandibular body osteotomy after using a 2.0 miniplate system. Nine adult mongrel dogs were subjected to unilateral continuous defect through an osteotomy between the mandibular 3rd and 4th premolars. Two four-hole miniplates were placed in accordance with the Arbeitgeimeinschaft für Osteosynthesefragen Manual. Miniplates adapted to the alveolar processes were fixed monocortically with 6.0-mm-length titanium alloy self-tapping screws, whereas miniplates placed near the mandible bases were fixed bicortically. At 2, 6 and 12 weeks, three dogs were sacrificed per period, and the osteotomy sites were removed, divided into three thirds (Tension Third, TT; Intermediary Third, IT; Compression Third, CT) and prepared for conventional and polarized light microscopy. At 6 weeks, while the CT repaired faster and showed bone union by woven bone formation, the TT and IT exhibited a ligament-like fibrous connective tissue inserted in, and connecting, newly formed woven bone overlying the parent lamellar bone edges. At 12 weeks, bone repair took place at all thirds. Histometrically, proportions of newly formed bone did not alter at TT, IT and CT, whereas significantly enhanced bone formation was observed for the 12-week group, irrespective of the third. The results demonstrated that although the method used to stabilize the mandibular osteotomy allowed bone repair to occur, differences in the dynamics of bone healing may take place along the osteotomy site, depending on the action of tension and compression forces generated by masticatory muscles.

Section: Discussionsupporting

confidence: 83%

Section: Discussionmentioning

confidence: 95%

Bone repair in mandibular body osteotomy after using 2.0 miniplate system – histological and histometric analysis in dogs

Lucas

Int J Experimental Path

et al. 2008

“…Good osteotomy reduction was obtained and maintained throughout the observation period of 12 weeks and no implant failure occurred. Similar results were reported on experimental studies and clinical trials 5,6,8 .…”

Section: Discussionsupporting

confidence: 89%

“…Miniaturized implants are desirable because of the limited surgical field observed in these cases. Besides that, smaller plate systems minimize tissue trauma and facilitates preservation of the periosteal blood supply [1][2][3][4][5] . The crescent clinical application of this method is also observed in small animal surgery 6 .…”

Section: Introductionmentioning

confidence: 99%

Miniplate 1.5 fixation for the repair of mandibular osteotomies in cats

et al. 2011

Purpose: To evaluate the application of the maxillofacial miniplate 1.5 in the repair of unilateral mandibular osteotomies in cats. Methods: Twelve adult cats were divided into two groups. In group 1 (n=6), the osteotomy was performed in the body of the mandible, behind the 1st molar. In group 2 (n=6), the osteotomy was performed between the 4th premolar and 1st molar. The osteotomy was fixed with a titanium miniplate 1.5. Oral alimentation was reinitiated 24 hours after surgery. Cats were euthanized at 12 weeks postoperative. Results: Radiographs taken 1 week after surgery showed a radiolucent line. The osteotomy line was not more visible on the radiographs taken at 12 weeks postoperative. Macroscopic examination confirmed alignment and bone union of operated hemimandibles. Histological examination showed formation of woven bone within the osteotomy line. The percentage of bone tissue at these areas was measured by the histometry. There was no statistically significant difference between the values of group 1(75.07 ± 5.99) and group 2 (74.76 ± 8.54) (Mann-Whitney's test p= 0.469). Conclusion: We concluded that the use of miniplate 1.5 for the fixation of mandibular osteotomy in cats provided the main goals in the treatment of mandibular fractures: bone union, normal dental occlusion and immediate return to oral alimentation.

“…Besides that, smaller plate systems are desirable because of the limited surgical field observed in these cases. The crescent clinical application of this method is also observed in small animal surgery [1][2][3][4][5] .…”

Section: Introductionmentioning

confidence: 99%

Miniplate fixation for the repair of segmental mandibular defects filled with autogenous bone in cats

et al. 2011

PURPOSE: To evaluate the use of maxillofacial miniplate 1.5 in the repair of segmental mandibular defects filled with autogenous bone in cats. METHODS: Twelve adult cats were divided into two groups. A segmental defect of 4mm was created in one of the hemimandibles and filled with autogenous iliac crest bone graft. The operated hemimandible was fixed with a 1.5mm titanium miniplate. In group 1 (n=6), the defect was performed in the body of the mandible, behind the 1st molar. In group 2 (n=6), the defect was performed between the 4nd premolar and 1st molar, with extraction of the 1st molar. Oral alimentation was reinitiated 24 hours after surgery. Cats were euthanized at 20 weeks postoperative. RESULTS: Incorporation of the graft was suggested by the radiographs taken 20 weeks after surgery. Macroscopic examination confirmed alignment and bone union of operated hemimandibles. Histological examination showed formation of woven bone in rostral and caudal mandible/graft interfaces. The percentage of bone tissue at these areas was measured by the histometry. There was no statistically significant difference between the values of group 1(64.48 ± 4.51) and group 2 (71.69 ± 14.47) (Mann-Whitney's test p= 0.294). CONCLUSION: The use of miniplate 1.5 for the fixation of mandibular defects filled with autogenous bone in cats provided the main goals in the treatment of mandibular fractures: bone union, normal dental occlusion and immediate return to oral alimentation.