Strength of denture base resins repaired with auto- and visible light-polymerized materials.

PURPOSE: Clinicians are still confused about the choice of repair method, which depends on factors such as the length of time required for processing, the mechanical strength of the repaired material, and the effect of stress concentration in the acrylic resins before the repair. The aim was to determine the impact and flexural strength characteristics, such as stress at yield, Young's modulus, and displacement at yield of denture base resins fractured and repaired by three methods using heat-, auto-, and visible light-polymerized acrylic resins. MATERIAL AND METHODS: For impact and flexural strength tests, 18 rectangular specimens measuring 50 x 6 x 4 mm(3) and 64 x 10 x 3.3 mm(3), respectively, were processed using Impact 2000, Lucitone 550, Impact 1500, and QC-20 acrylic resins. Fracture tests were performed according to ISO1567:1999. Afterward, all fractured specimens were stored in distilled water at 37 degrees C for 7 days, and then repaired with (1) the same acrylic resin used for specimen fabrication (n = 6), (2) an autopolymerized acrylic resin (TruRepair, n = 6), and (3) a visible light acrylic resin (Versyo.com, n = 6). The repaired specimens were again submitted to the same fracture tests, and the failures were classified as adhesive or cohesive. Data from all mechanical tests after repair by the different methods were submitted to two-way ANOVA, and mean values were compared by the Tukey test. RESULTS: All acrylic resins showed adhesive fractures after impact and flexural strength tests. Differences (p < 0.05) were found among repair methods for all acrylic resins studied, with the exception of displacement at yield, which showed similar values for repairs with auto- and visible light-polymerized acrylic resins. The highest values for impact strength, stress, and displacement at yield were obtained when the repair was made with the same resin the specimen was made of. CONCLUSION: Denture base acrylic resins repaired with the same resin they were made of showed greater fracture strength.

Treatment of painful post-traumatic peripheral neuropathy with capsaicin in an edentulous patient with extreme resorption in the mental region: a case report.

AIM: The aim of this report is to present a clinical case of extensive alveolar resorption in the mental region of the mandible of a complete denture wearer for which capsaicin was used for alleviation and remission of post-traumatic painful peripheral neuropathy. BACKGROUND: Resorption of the residual ridge occurs in a chronic and progressive manner, altering the configuration of the ridge and the mucosa covering it and subsequently compromising the stability of the complete denture prosthesis. Individual variability associated with such factors as gender, age, edentulous period, nutrition, excessive load and compression on the ridge, parafunctional habits, occlusal instability, and maladaptation of the prosthesis may have a role in the rate and manner of bone loss. REPORT: A 62-year-old woman, edentulous at the age of 30, presented with complaints of pain and spontaneous "electrical shocks" in the mucosa under her mandibular complete denture. The pain increased while chewing approximately two years ago due to the pressure of this denture on her supporting tissues. The patient indicated the level of pain corresponded to a score of ten out of ten on the Visual Analogical Scale (VAS). Treatment included denture replacement and topical application of capsaicin gel using a custom tray technique. SUMMARY: The review of the literature and the results obtained from the management of this case have served to emphasize how much neuropathic pain research has demonstrated the complexity of its neurophysiologic mechanism due to the lack of association with any somatic manifestation. During the fabrication of a new lower denture the topical application of capsaicin was shown to be effective in the relief and remission of the painful symptoms of the neuropathy as of this writing.

Management of the oral manifestations of senile purpura in an edentulous patient: a case report.

Senile purpura occurs because of a weakness of the vascular supporting tissues mainly caused by aging and is most often seen on the dorsal surface of the hands and the extensor surfaces of the forearms, and has also been observed in the oral mucosa of elderly patients. These red lesions present as sharply margined subcutaneous hemorrhagic spots and are due to trauma, such as damage to the endothelium of small blood vessels, or a coagulation defect. They can also be due to reduced perivascular support, or capillary fragility and permeability, or a combination of all of these factors. Oral manifestation of senile purpura can also be induced by long periods of medication use leading to fragile areas of the mucosa. The presence of senile purpura requires continuous follow-up since drug-induced purpura may cause plaque function alterations. An accurate diagnosis in elderly complete denture wearers can minimize bleeding and prevent possible development of ulcerations under the dentures, especially during the adaptation period to the prosthesis. This case report, presents the care and 3-year follow-up of a 66-year-old woman with complete dentures who presented with the oral manifestations of senile purpura caused by the continued use of several medications.