Abstract Objective To evaluate the effect of restorative strategy (fiber post vs cast post and core), coronal height (0 mm vs 2 mm) and thickness (higher than 1 mm vs lower than 1 mm) on survival rate, fracture resistance and stress distribution. Material and Methods Seventy-two bovine teeth were cleaned and allocated in six groups (n = 12). Twenty-four teeth were sectioned at 13 mm length (no remaining coronal structure) and forty-eight were sectioned at 15 mm (2 mm remaining coronal structure). Half of the forty-eight had remaining coronal thickness lower than 1 mm and the other half had thickness higher than 1 mm. All root canals were prepared at 10 mm (luting length), fiber posts were cemented in thirty-six specimens and cast post and core in other thirty-six. All teeth were restored with metallic crowns. Specimens were submitted to 1.5 million cycles (100 N, 45°, 10 Hz at 2 mm below incisal edge) and evaluated at each 500,000 cycles to detect failures. Specimens that survived were submitted to load to fracture test. Bidimensional (Rhinoceros® 4.0) models were obteined survival data submitted to Kaplan-Meier (α=0.05) analysis and load to fracture values submitted to ANOVA and Tukey tests (α=0.05). Results Groups without remaining coronal structure showed survival rates lower than other groups (p=0.001). ANOVA showed higher values of load to fracture for groups with coronal thickness higher than 1 mm (p=0.0043). Finite element analysis showed better stress distribution in groups with remaining coronal structure and restored with fiber post. Conclusion Specimens without remaining coronal structure have lower survival rates. Specimens with remaining structure lower than 1 mm and without coronal structure support the same load to fracture value independently of the restorative strategy.

RESUMO O tratamento das neoplasias em região de cabeça e pescoço pode deixar sequelas que afetam a qualidade de vida do paciente durante e após o tratamento. A comunicação buconasosinusal decorrente da ressecção cirúrgica parcial ou total do palato traz ao paciente alterações na função mastigatória, estética, fonética e de deglutição o que pode levar a um isolamento social do indivíduo. Em vista disso, a atuação do cirurgião dentista junto à equipe multiprofissional de atendimento ao paciente oncológico se faz fundamental, podendo contribuir no diagnóstico, auxiliar no manejo de complicações do tratamento quimioterápico/radioterápico, e na reabilitação bucomaxilofacial, sendo esta uma alternativa para melhorar a qualidade de vida do paciente, pois visa restabelecer as funções alteradas em decorrência do procedimento cirúrgico. O presente estudo relata o caso de uma paciente portadora de carcinoma adenóide cístico na maxila submetida à maxilectomia parcial, deixando como seqüela a comunicação buconasosinusal. O acompanhamento odontológico foi realizado no Hospital Escola da Universidade Federal de Pelotas no pré-operatório, durante e após o tratamento. No momento a paciente está reabilitada com uma prótese obturadora em acompanhamento pela equipe de odontologia e pelo cirurgião de cabeça e pescoço.

ABSTRACT Treatment of cancers of the head and neck may provoke sequelae that affect the quality of life of patients during and after treatment. Mouth-sinus communication resulting from partial or total surgical resection of the palate leads to the patient experiencing dysphagia, dysphonia and trismus, which can lead to social isolation of the individual. As a result, the work of the dental surgeon, together with the multidisciplinary team caring for cancer patients, is fundamental and can help with the diagnosis, assist in the management of chemotherapy and radiotherapy complications and enable postsurgical rehabilitation. The present study reports the case of a patient with adenoid cystic carcinoma in the right maxilla, who underwent a partial maxillectomy, the resulting sequela being mouth-sinus communication. The dental treatment was performed at the Hospital of the Federal University of Pelotas preoperatively, during and after treatment. At this time the patient is rehabilitated with an obturator prosthesis and is being monitored by the dental team and the head and neck surgeon.

RESUMO O tratamento cirúrgico para os cânceres de palato pode resultar em comunicação buco-nasal/sinusal, o que interfere negativamente na capacidade de deglutição, fonação e mastigação dos pacientes, com refluxo dos alimentos ingeridos para a cavidade nasal, reduzindo sua qualidade de vida. Neste artigo, objetiva-se relatar como foram reabilitados proteticamente, no período de 2011 a 2015, três pacientes oncológicos com diferentes tipos de câncer de palato submetidos à maxilectomia parcial com comunicação buco-sinusal ou buco-nasal como sequela pós-operatória. As próteses foram confeccionadas por Cirurgiões-dentistas residentes no serviço de Residência Multiprofissional em Atenção à Saúde Oncológica do Hospital Escola da Universidade Federal de Pelotas (HE/UFPel). Um dos pacientes é edêntulo total, o segundo é dentado parcial e no terceiro caso a paciente é totalmente dentada, necessitando apenas do obturador. A confecção das próteses obturadoras seguiu as etapas das próteses convencionais, observadas particularidades principalmente nas fases de planejamento, moldagem e instalação e adaptação da prótese. Em todos os casos observou-se melhora na fala imediatamente à instalação da prótese e os pacientes relataram maior facilidade ao se alimentar.

ABSTRACT Surgical treatment for palate cancers can result in oral-nasal/sinus communication, which impairs the swallowing, speech and chewing ability of patients with reflux of ingested food into the nasal cavity, reducing their quality of life. This article aims to report how three cancer patients, with different types of palate cancer undergoing partial maxillectomy with oroantral or oral-nasal communication as postoperative sequelae were prosthetically rehabilitated from 2009 to 2015. The prostheses were made by dental-surgeons interns in the service of the Multidisciplinary Residency in Oncological Healthcare of the Hospital School of the Federal University of Pelotas (HE/UFPel). One of the patients is completely edentulous, the second partially toothed and in the third case the patient is totally toothed, only requiring the obturator. The creation of prosthetic rehabilitation followed the steps of conventional prostheses, especially observing the particularities in the planning, molding, installation and adjustment stages of the prosthesis. In all cases there was improvement on speech immediately after the prosthesis installation and patients reported greater ease to feed.