EVALUATION OF COMPLICATIONS AFTER ENDOSCOPY ASSISTED OPEN REDUCTION AND INTERNAL FIXATION OF UNILATERAL CONDYLAR FRACTURES OF THE MANDIBLE. RETROSPECTIVE ANALYSIS 2010-2015.

BACKGROUND: The authors present their experience with endoscopy assisted open reduction and internal fixation of condylar fractures of the mandible. Their results are presented in a retrospective study of 33 patients with unilateral subcondylar fracture, who underwent a surgical procedure between 2010 and 2015. Reduction and fixation, stability of occlusion 12 months after the operation and also presence of complications were evaluated. RESULTS: Satisfactory reduction (anatomic or physiologic) was achieved in 31 patients. Stability of occlusion was worse in 1 patient (due to condylar absorption). Complications included mainly inflammatory complications (4 patients) and temporary paresis of the facial nerve (3 patients). Impaired function of temporomandibular joint was not reported in any of the patients. CONCLUSION: Endoscopy assisted open reduction and internal fixation is an alternative to classical surgical procedures, however it requires special instrumentarium and experienced surgical team.

Stem cells regenerative properties on new rat spinal fusion model.

Stem cells biology is one of the most frequent topic of physiological research of today. Spinal fusion represents common bone biology challenge. It is the indicator of osteoinduction and new bone formation on ectopic model. The purpose of this study was to establish a simple model of spinal fusion based on a rat model including verification of the possible use of titanium microplates with hydroxyapatite scaffold combined with human bone marrow-derived mesenchymal stem cells (MSCs). Spinous processes of two adjacent vertebrae were fixed in 15 Wistar rats. The space between bony vertebral arches and spinous processes was either filled with augmentation material only and covered with a resorbable collagen membrane (Group 1), or filled with augmentation material loaded with 5 × 106 MSCs and covered with a resorbable collagen membrane (Group 2). The rats were sacrificed 8 weeks after the surgery. Histology, histomorphometry and micro-CT were performed. The new model of interspinous fusion was safe, easy, inexpensive, with zero mortality. We did not detect any substantial pathological changes or tumor formation after graft implantation. We observed a nonsignificant effect on the formation of new bone tissue between Group 1 and Group 2. In the group with MSCs (Group 2) we described minor inflamatory response which indicates the imunomodulational and antiinflamatory role of MSCs. In conclusion, this new model proved to be easy to use in small animals like rats.

Arthroscopic lysis and lavage in patients with temporomandibular anterior disc displacement without reduction.

The authors prospectively analysed 50 patients with chronic anterior disc displacement without reduction, who underwent arthroscopic lysis and lavage of the temporomandibular joint (TMJ). Patients with symptoms lasting less than 1 year were assigned to Group A (n=28) and patients with symptoms lasting more than 1 year to Group B (n=22). The most common problems were inflammatory changes of synovial and retrodiscal tissue (Group A, 71%; Group B, 82%). Fibrous adhesions were present in 14% of Group A patients and 45% of Group B patients. Degenerative changes of the disc and articular surface were present in 4% of Group A patients and 32% of Group B patients. Mouth opening increased 123% from baseline in Group A, and 112% in Group B (P<0.05). Pain decreased significantly in both groups (Group A, 2.5 points; Group B, 1.68 points; P<0.05). In conclusion, almost all patients with chronic anterior disc displacement without reduction benefited from arthroscopic lysis and lavage of the TMJ. Patients with a shorter duration of symptoms problems benefited more than those with a longer duration. Arthroscopic lysis and lavage of the TMJ is safe and beneficial in chronic anterior disc displacement without reduction.

Stability of the miniplate osteosynthesis used for sagittal split osteotomy for closing an anterior open bite: an experimental study in mini-pigs.

Bilateral sagittal split osteotomy of the mandible with counterclockwise rotation of the occlusal plane alone has traditionally been considered the least stable treatment method. Two miniplates on each side of the osteotomy may resolve this problem. The authors compared early vertical and transverse stability of a simple mandibular advancement (group A), mandibular advancement with counterclockwise rotation (CCW) stabilized with one miniplate (group B), and two miniplates (group C) on mini-pig mandibles mounted on a custom-made loading unit. Two miniplates markedly increased the resistance to vertical bite forces. On a 100-N load, a median of dislocation of 0.53 mm, 0.46 mm, and 0.23 mm was achieved in groups A, B, and C, respectively. The difference was statistically significant between groups A and B in comparison with group C. The results of transverse displacement were not statistically significant. The use of two miniplates in larger shifts, as well as in CCW cases, increases stability in the vertical direction.

Factors affecting the stability of bilateral sagittal split osteotomy of a mandible.

Stability of bilateral sagittal split osteotomy (BSSO) is an important goal for every surgeon. In the article factors influencing stability of the surgery result are reviewed. Special emphasis is given to different types of fixation of bone fragments. Their advantages and disadvantages in clinical use are discussed. Relapse after BSSO is usually classified as early and long-term relapse. Early relapse is usually caused by movements at the osteotomy site or temporomandibular joint sag and should be called surgical displacement. Long term relapse happens due to the progressive temporomandibular joint condylar resorption, which causes a lost of condylar and mandibular ramus height. Four different types of fixation were described in orthognatic surgery: rigid intermaxillary fixation, osteosuture, osteosynthesis and fixation with biodegradable materials.