Bone healing after biodegradable mini-plate fixation

ABSTRACT PURPOSE: To compare bone healing in mandibular vertical body osteotomies (MVBO) after fixation with a resorbable 2.0mm-profile fixation system in the first and third postoperative months in rabbits. METHODS: Twenty hemimandibles of ten rabbits were divided into two groups according to duration of resorbable fixation-one or three months. The MVBOs were performed and one four-hole, resorbable, 2.0mm mini-plate fixation system was used on each side. The computed tomography (CT) scans, scanning electron microscopy (SEM), and histomorphometric outcomes of groups I and II were compared. RESULTS: Significant differences were found between the one- and three- month assessments in terms of newly formed bone ratio values (p<0.05). There was more new bone formation at the third month on both the CT and histomorphometric examinations. A better adaptation of the bone tissues to the resorbable mini-plate and screws was observed on SEM at three months. CONCLUSION: The resorbable mini-plates provided a fixation stable enough to allow immediate oral alimentation and callus formation in both groups.

Tratamiento simultáneo de anquilosis temporomandibular unilateral congénita y del microlaterognatismo asociado / Simultaneously treament of congenital unilateral temporomandibular ankylosis and consecutive microlatherognathism

Este artículo tiene como objetivo reportar los resultados obtenidos a corto y largo plazo, del tratamiento con enfoque multidisciplinario de una anquilosis unilateral congénita de la articulación temporomandibular asociada a un síndrome de malformación embrionaria, en un niño de 12 años de edad, en el que se utilizó un distractor externo bidimensional con un doble propósito: como fijador para mantener el espacio logrado con la artroplastia y como distractor para elongar la rama mandibular hipotrófica, activado 5 días después de la osteotomía, con el objetivo de eliminar la anquilosis y el microlaterognatismo mandíbular consecutivo de ella, simultaneamente de manera funcional y dinámica(AU)

The paper reports the short- and long-term results obtained from the multidisciplinary treatment of a congenital unilateral ankylosis of the temporomandibular joint associated to an embryonic malformation in a 12-year-old boy, using an external bidimensional distraction device with a two-fold purpose: as fixator to maintain the space achieved by arthroplasty, and as distractor to elongate the hypotrophic mandibular branch, activated 5 days after osteotomy, with the purpose of eliminating ankylosis and consecutive mandibular microlaterognatism, both functionally and dynamically(AU)