Effect of 50 to 60°C heating on osseointegration of dental implants in dense bone: an in vivo histological study.

OBJECTIVES: To evaluate, in vivo, the effects of bone temperatures increased up to 60°C introduced before implant insertion on titanium implant osseointegration. MATERIALS AND METHODS: Twenty-four acid etched and sandblasted implants (Cortex Dental Implants) were inserted in the inferior edge of sheep mandibles. Osteotomic sites were randomly divided into 3 groups before inserting the implant. In test 1 group and in test 2 group, implant sites were overheated, respectively, up to 50°C for 1 minute and 60°C for 1 minute, with an electronic controlled probe of 3 mm in diameter and 10 mm in length. Osteotomic sites in control group were not overheated. Implants were inserted according to standard procedures. After 2 months healing, % bone implant contact (%BIC) and infrabony pockets' depth were measured. Unpaired t test was applied to find statistical differences between groups. RESULTS: No implant failure occurred. No statistical significant difference in %BIC was found among groups. Histological analysis showed that mean infrabony pockets were statistically deeper in 60°C group than in other groups. CONCLUSIONS: Bone temperature up to 60°C for 1 minute does not seem to significantly impair titanium dental implant osseointegration. Bone damage signs evident in the 60°C group suggest that careful drilling procedure with sufficient irrigation is necessary to avoid periimplant infrabony pockets' formation. More in vivo evaluations are needed to identify what is the value of bone temperature increase for irreversible inhibition of implant osseointegration.

Comparison Among Clark's, Breslow's, and TNM classifications for cutaneous head and neck malignant melanoma.

This retrospective study was carried out to assess the prognostic value of three classification systems used for staging cutaneous head and neck malignant melanoma (CHNME). Fifty-three patients with histologically proven CHNME were analyzed. Thirty patients were never treated before admission, whereas 23 (43.4%) had a second radical resection of the primary tumor location, 9 (17%) had neck nodes, none had distant metastasis, and all had a minimum of 5 years of follow-up. Results show that T-stage is the most important clinical prognostic parameter, whereas Clark's and Breslow's classifications have lower impact in defining prognosis. Sites of primary tumor determines different clinical outcomes, but this does not reach statistically significant values. A second surgery on the primary tumor location is possible and is effective toward survival. No statistical differences were noted between the previously untreated and treated groups. Neck nodes have to be removed with neck dissection, and this regimen can improve the clinical outcome; however, only 40% of neck positive patients survive more than 5 years.

Clinical parameters in T1N0M0 lower lip squamous cell carcinoma.

This retrospective study was carried out to asses the clinical outcome of T1 (i.e., tumor 2 cm or less at greatest dimension) squamous cell carcinoma of the lower lip (SCCLL) and verify the impact of some clinical parameters on prognosis. Fifty-seven patients with histologically proven T1 SCCLL were analyzed. Fifty-two patients were never treated before admission, whereas five (8.8%) had a second radical resection of the primary tumor location; none had neck nodes (i.e., N0) or distant metastasis (i.e., M0). The global disease-specific survival rate at 32 months was 100%, irrespective of grading and type of surgery, and thus no differences were statistically detected. Therefore, we concluded that radical tumor resection is a viable procedure for T1 SCCLL, irrespectively of grading. In addition, a second surgery on the primary tumor location is possible and has effectiveness on survival. Finally, neck dissection is not necessary in cases of T1 SCCLL.