Antônio Materson Silva

Oral rehabilitation of severely worn dentition using an overlay for immediate re-establishment of occlusal vertical dimension

The aim of this study was to describe the treatment used in an elderly patient presenting with bruxism and dental erosion, with good gingival health and bone support, but with decreased occlusal vertical dimension (OVD). The oral rehabilitation of elderly patients presenting with bruxism in association with tooth erosion has been a great challenge for dentists. The loss of OVD, the presence of occlusal instability and the absence of an effective anterior guide due excessive dental wear, can damage stomatognathic system (SS) biology, the function and the aesthetics. In the first treatment stage, an overlay removable partial denture (ORPD) was fabricated for the immediate re-establishment of function and aesthetics. After a 2-month follow up, with the patient presenting no symptoms, a second rehabilitation stage was accomplished, with fixed and removable prostheses. Oral rehabilitation with an ORPD was able to re-establish the SS biology, but a correct diagnosis and treatment plan are essential for success. The ORPD is a non-invasive and reversible restoring modality for general dentists that allow the re-establishment of the patients immediate aesthetics and function at low cost.

The role of polymerization cycle and post-pressing time on tooth movement in complete dentures

This study analyzed the influence of polymerization cycle and post-pressing time on tooth movement in complete dentures. Forty maxillary complete dentures were fabricated and randomly assigned to 8 groups (n = 5); the polymerization cycle (conventional long cycle in water bath, fast cycle in boiling water, and by microwave energy) and the post-pressing time (immediate and 6 hours) were varied. Metal reference pins were placed on the incisal border of the central incisors (RI and LI), on the buccal cusp of the first premolars (RP and LP), and on the mesiobuccal cusp of the second molars (RM and LM). Two transverse and 2 anteroposterior distances were measured with a linear optical microscope (Olympus Optical Co., Tokyo, Japan) with an accuracy of .0005 mm, before and after processing the complete dentures. The data collected were submitted to analysis of variance (ANOVA) and the Tukey Test at a significance level of 5%. When Clássico, a conventional heat-polymerizable acrylic resin, was polymerized by microwave energy, tooth movement was statistically significant for 2 distances, with the highest value being observed for the 6-hour post-pressing time. Onda-Cryl microwave acrylic resin processed by microwave energy presented the lowest tooth movement for 2 distances, considering the 6-hour post-pressing time. QC-20 acrylic resin presented no statistically significant change considering both post-pressing times in each distance evaluated. Tooth movement showed an asymmetric behavior, so the mastering of the processing method is essential to the precise execution of all laboratory steps, irrespective of the polymerization cycle and post-pressing time used.

Individual lithium disilicate crowns in a full-arch, implant-supported rehabilitation: a clinical report.

This clinical report presents the clinical outcome of a maxillary full-arch implant-supported fixed rehabilitation with lithium disilicate reinforced glass ceramic monolithic crowns opposing a mandibular metal-acrylic implant-supported fixed rehabilitation in a 62-year-old woman. Eight implants were successfully placed (four maxillary, four mandibular), and no complications occurred in the postoperative or maintenance periods. Six months after delivery, the maxillary and mandibular prostheses were found to be clinically, biologically, and mechanically stable, and the patient was satisfied with the esthetics and her ability to function. Although the present indications for the use of lithium disilicate are still restricted to tooth-borne restorations, it is possible to successfully rehabilitate edentulous patients through implant-supported fixed prostheses using lithium disilicate reinforced glass ceramic monolithic crowns.

Pre-Prosthetic Orthodontic Treatment Using Personalized Elastic Separators for Optimization of Emergence Profile in Esthetic Crowns: A Clinical Report

Restoring a misaligned tooth with an inadequate contact point is a challenge to the practitioner. In some instances, teeth that could be repositioned and adequately restored are extracted. Thus, the aim of this article was to describe a treatment using orthodontic and prosthetic techniques to restore esthetics and function in a patient with a distally drifted maxillary lateral incisor. The patients functional and esthetic expectations were successfully met with the outlined treatment.

Surgical and prosthetic considerations to rehabilitate an ocular defect using extraoral implants: a clinical report.

This clinical report shows the use of extraoral implants to rehabilitate an ocular defect, focusing the surgical and prosthetic procedures. Using local anesthesia and a surgical template obtained from the diagnostic wax ocular pattern, two cylinder dental implants were strategically placed in the lateral aspect of the right infraorbital region. Four months later, an acrylic framework including two spherical magnets was made using plastic UCLA abutments. After casting laboratory steps, a customized silicon prosthetic appliance was fabricated from the diagnostic wax ocular pattern and attached to the Co-Cr framework, observing its profile and seating aspects. The patient was satisfied with the treatment result, due to the retention, esthetics, and adhesive-free method to anchor his ocular prostheses.

Short-term report of an ongoing prospective cohort study evaluating the outcome of full-arch implant-supported fixed hybrid polyetheretherketone-acrylic resin prostheses and the All-on-Four concept

BACKGROUND More research is needed on the study of new materials for fixed prosthetic implant-supported rehabilitations. PURPOSE The purpose of this study was to report the short-term outcome of full-arch implant-supported fixed hybrid polyetheretherketone (PEEK)-acrylic resin prostheses and the all-on-four concept. MATERIALS AND METHODS This prospective cohort clinical study included 37 patients (29 women, eight men) with an average age of 60 years (range: 38-78 years) with 49 full-arch hybrid PEEK-acrylic resin prosthesis supported by implants through the all-on-four concept. Primary outcome measures were prosthetic survival. RESULTS Two patients with two maxillary prostheses were lost to follow-up. One patient with a double full-arch rehabilitation fractured the mandibular PEEK framework, rendering a 98% prosthetic survival rate. No implants were lost. The average (SD) marginal bone remodeling after 1 year of follow-up was 0.37 mm (0.58 mm). Technical complications concerning the veneer adhesion occurred in six patients and were resolved in all patients (with exception of the patient with prosthetic failure) through the creation of mechanical retentions and changing the bonding primer. Mechanical complications occurred in three patients and five prostheses consisting in prosthetic screw loosening (n = 2 patients) and fracture of the acrylic resin teeth (the patient with a prosthetic failure). CONCLUSIONS Within the limitations of this study, the results suggest that hybrid polymer (PEEK)-acrylic resin prostheses supported by implants for full-arch rehabilitation may represent a valid treatment option, still requiring longer-term validation.

Effect of restoration technique on stress distribution in extensively destroyed premolars: a finite element analysis study

Objetivo: Analisar, por meio do metodo dos elementos finitos, a distribuicao de tensoes em elemento dental pre-molar inferior unirradicular restaurado de duas maneiras distintas. Metodos: A simulacao laboratorial considerou as seguintes situacoes: 1) pre-molar restaurado com nucleo metalico fundido em liga aurea e coroa em cerâmica; 2) pre-molar restaurado com pino de fibra de vidro, nucleo de preenchimento em resina composta e coroa em cerâmica. Para isso foi utilizado um modelo bidimensional de um pre-molar com aplicacao de carga de 300N nas direcoes axial e obliqua com uso de programa ANSYS para Windows. Resultados: Diante da carga axial, foi observada uma maior concentracao de tensoes na regiao do nucleo fundido (166 Mpa). Na simulacao de carga obliqua, observou-se uma concentracao de tensoes na parede radicular vestibular, interna e externamente, no dente restaurado com nucleo fundido (222 Mpa). Nas duas situacoes em estudo, o pino de fibra de vidro e nucleo de preenchimento dissipou, com maior uniformidade, a tensao recebida (55 a 111 Mpa). Conclusao: Esses dados sugerem que o uso de pino de fibra pre-fabricado e nucleo de preenchimento em resina composta pode ser mais vantajoso que a indicacao de nucleo fundido, sob o ponto-de-vista biomecânico, em dente pre-molar inferior unirradicular.