Urbanization on Population Abundance of Some Passerines in the Outskirts of Dubai

Abstract

A segmental mandibulectomy and immediate mandibular reconstruction using a Ti-mesh tray and particulate cancellous bone and marrow was planned. The spontaneousregeneration of the coronoid process was observed on the reconstructed mandible. On the CT slabs, the reattachment of the masseter and temporal muscle was confirmed. Before treatment, the transversal growth of her maxilla was asymmetrical. After the mandibular reconstruction and prosthodontic treatment, her maxilla grew back with bilateral symmetry. The occlusal loading on her mandible appeared symmetrically via an FEA. In addition, the stress was concentrated in the external oblique ridge, and the graft bone remodeled into the anatomical configuration. Through this case, it is suggested that the reattachment, the healthy growth of masticatory muscles, and the rehabilitation of oral function contributed to spontaneous bone regeneration and remodeling in the mandible, as well as the preservation of periosteum.

Introduction

In this paper, we present a case of spontaneous-regeneration of the reconstructed mandible, and discuss on the relationship between regeneration and muscle reattachment based on the findings of Computer Tomography (CT). In addition, the influences of occlusal relation and oral function on the mandibular growth were investigated through the analysis of occlusal force and Finite Element Analysis (FEA).

Materials and Methods

In January 11, 1995 a 10-year-old girl with a 5 months history of hard non movable painless mass in the posterior region of the left mandible was referred to Oral and Maxillofacial clinic at the Jordan University of Science and Technology. Extra-oral examination showed an enlargement of the left mandible, with mild facial asymmetry. A tangible lymph node in the left sub mandibular region was also found. Intraoral examination revealed a minimal expansion of the body extending from the left first premolar to the angle, the buccal sulcus was obliterated. The overlying mucosa was normal, whereas the first, second premolars, the first and second molars were mobile, with no signs of inflammation or infection and without any exudation.

Results and Discussion

The patient was an 11 year-old girl. She complained of facial swelling and visited our hospital. As for 3 years history, she slowly had an enlargement of painless swelling on the left cheek. Visual inspection showed severe swelling from the left mandibular angle to the ramus region. Manual examination showed diffuse, non-tender, hard-texture swelling. An intraoral examination showed buccolingual expansion of the mandibular alveolus in the left molar region with overlying of normal mucosa. Her left molars were vital and inclined to the lingual side. There was no neural disturbance.

Conclusion

Spontaneous bone regeneration is an uncommon phenomenon may take place following bone loss. Osteogenesis is the formation of new bone from osteoprogenitor cells in a wound, it is regarded as responsible for spontaneous bone regeneration from the periosteum, remnants of resected bone and uncommitted connective tissue cells in the region [19]. New bone formation occurs through osteoinduction, osteoconduction and osteogenesis. The committed and uncommitted undifferentiated mesenchymal cells in the periosteum and endosteum contribute to fracture healing. Also, mesenchymal cells in connective tissue can be induced by remaining bone fragments to form new bone and marrow [18,20,21]. New bone was discovered only during routine postoperative clinical and radiographic examinations. A review of the literature showed that a total of 33 reports of spontaneous bone regeneration of the mandible in the English literature including the present case [22].