Changes in the pre-surgical treatment planning using conventional spiral tomography.

OBJECTIVE: To investigate variation in the pre-surgical treatment planning after using conventional spiral tomography in addition to conventional radiographic exams. MATERIAL AND METHODS: Twenty-nine partial or fully edentulous patients referred to implant therapy were selected and submitted to periapical, panoramic and conventional cross-sectional tomography exams. Pre-surgical treatment planning of 120 potential implant sites in 69 edentulous areas was performed by two independent experienced dental implant surgeons. After clinical examination, pre-surgical planning was made using only periapical and panoramic exams. Examiners were requested to reformulated initial planning after assessing tomographic images. Four treatment parameters were evaluated: length and width of implants, need of bone grafting and need of other surgical procedures. RESULTS: Implant length and width remained unchanged in 60.2% and 87.2% of cases, respectively. No difference in length (P=0.576) and width (P=1) scores was observed in treatment planning with and without tomography. Variation in implant dimension was not affected by location of edentulous areas. Bone grafting and other surgical procedures significantly changed after tomograms (P<0.001), independent of the location of edentulous areas. In 15.8% and 5.3% of cases bone grafting and other procedures were planned only after tomograms, respectively. Significant differences were observed in all maxillary and mandibular regions. CONCLUSION: Conventional spiral tomography plays an important role in pre-surgical treatment planning, increasing clinician's certainty of the need of additional surgical procedures (bone grafting, sinus lifting, and others) in pre-surgical treatment stage.

Low-grade central osteosarcoma of the mandible: a case study report.

Low-grade central osteosarcoma is a rare type of osteosarcoma with peculiar clinical radiographic and microscopic features. The aim of this article is to report and discuss a case of low-grade central osteosarcoma in the mandible of a 42-year-old woman. The patient reported sensing mild pain and tooth mobility for a period of 4 years, despite continuous dental treatment. Radiographic evaluation showed a mixed radiopaque/radiolucenct lesion in the body, ramus, coronoid process, and condyle of the left side of the mandible. Destruction of the mandibular cortex in the area was also observed. After incisional biopsy, the patient underwent hemimandibulectomy. Microscopic findings showed a tumor exhibiting spindle cells with nuclear hyperchromasia and no mitotic activity, irregular osteoid formation, and soft tissue infiltration. The immunohistochemical analysis of the expression of Ki-67, Cyclin B1, and PCNA proteins (cellular proliferation markers) revealed a very low Ki-67+ and Cyclin B1+ cell index (mean 7% and 3%, respectively), but a moderate number of PCNA+ cells (mean 49%). The 2 years of clinical and imaging postoperative follow-up showed no evidence of recurrence. Clinicians should be aware of these lesions, because histopathologicially low-grade central osteosarcoma may be misinterpreted as fibrous dysplasia.