INTRODUCTION: Despite discussion on the merit of various cephalometric superimposition methods, there remains a need to assess which one can be used in daily practice with reasonably accuracy and less working time. OBJECTIVE: The aim of this study was to investigate four methods of cephalometric superimposition by means of assessing the longitudinal changes in craniofacial morphology caused by growth and response of adolescents with Class I malocclusion to orthodontic treatment involving first premolar extraction. METHODS: Pretreatment (T1) and post-treatment (T2) standardized lateral cephalometric radiographs of 31 adolescents (20 females and 11 males), with Angle Class I malocclusion and indication of premolar extraction, participated in this study. Radiographs were digitized, traced and had structures identified by means of a cephalometric software. Four superimposition methods were used: Björk structural method, Steiner/Tweed SN line, Ricketts N-Ba line at N-point and Ricketts N-Ba line at CC-point. Positional changes were quantified by horizontal and vertical linear changes in the following cephalometric landmarks: anterior/posterior nasal spine (ANS and PNS), gnathion (Gn), Gonion (Go), Pogonion (Pog), A-point and B-point. Differences between T1 and T2 in horizontal and vertical positional changes for all superimposition methods were assessed by one-way analysis of variance (ANOVA) and Bonferroni correction (p < 0.05). RESULTS: There were no statistically significant differences among the cephalometric superimposition methods or when patients' sex was considered. CONCLUSION: Björk structural method, Steiner/Tweed SN line, Ricketts N-Ba line at N-point and Ricketts N-Ba line at CC-point methods were reliable and presented similar precision when the overall facial changes due to active growth and/or orthodontic treatment were examined.

Objective: To evaluate facial profile changes promoted by polymethyl methacrylate (PMMA) cement graft to reduce excessive gingival display due to hyperactivity of the elevator muscles of the upper lip during smiling. Methods: Eleven patients (all females, age range: 20 to 43 years) presenting gingival smile that were treated with PMMA cement grafts in a private clinic were selected for this retrospective study. Three angular and ten linear cephalometric facial profile measurements were performed preoperatively (baseline, T1) and at least 6 months postoperatively (T2). Differences between T1 and T2 were verified by Wilcoxon test, and the correlation between the thickness of the graft and facial profile changes was statistically evaluated by Spearman’s Coefficient test. The significance level was set at p< 0.05. Results: The nasolabial angle (p= 0.03) and the labial component of the nasolabial angle showed statistically significant differences (p= 0.04), with higher values in T2. No correlations were found between the graft thickness and the statistically significant facial profile changes (p> 0.05). Conclusions: The PMMA bone cement graft projected the upper lip forward, thereby increasing the nasolabial angle without affecting the nasal component. No correlations between the graft thickness and the facial profile changes were detected.

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The mouth and oropharynx cancer is the 6th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as "cabelo-de-negro". The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas.

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