Biomedical subjects

Wael Att

Publications and source records attributed to Wael Att.

4 recordsLinked to original sources

PubMed2006

Fracture resistance of single-tooth implant-supported all-ceramic restorations: an in vitro study.

STATEMENT OF PROBLEM: High-strength ceramic materials can be used to fabricate esthetic and stable implant-supported single-tooth restorations. No study was identified that compared the fracture resistance of individual components of single-tooth implant-supported all-ceramic restorative systems after artificial aging. PURPOSE: The purpose of this in vitro study was to evaluate the fracture resistance of single-tooth implant-supported all-ceramic restorations consisting of alumina all-ceramic restorations on different implant abutments and to identify the weakest component of the restorative system. MATERIAL AND METHODS: Forty-eight standardized maxillary central incisor alumina crowns (Procera) were fabricated for each of the 3 test groups (n = 16) (Control group Ti, titanium abutments; Group Al, alumina abutments; Group Zr, zirconia abutments) for the Replace implant system. The crowns were adhesively luted using a resin luting agent (Panavia 21) and artificially aged through dynamic loading and thermal cycling. Afterwards, all specimens were tested for fracture resistance using compressive load on the palatal surfaces of the crowns. Kruskal-Wallis analysis of variance and post hoc Wilcoxon rank sum tests were performed to test for differences in fracture resistance values (alpha = .05). RESULTS: All test specimens survived the artificial aging process using simulated oral conditions. No screw loosening was recorded. The median fracture resistance was 1454 N, 422.5 N, and 443.6 N for groups Ti, Al, and Zr, respectively. Significant differences were found for the fracture resistance comparisons of group Ti with groups Al and Zr (Kruskal-Wallis test, P < .001). The test results for the comparison of groups Al and Zr were not significant. CONCLUSION: All 3 implant-supported restorations have the potential to withstand physiologic occlusal forces applied in the anterior region.

Aluminum Oxide↗

PubMed2006

Fracture resistance of different partial-coverage ceramic molar restorations: An in vitro investigation.

BACKGROUND: The authors conducted a study to evaluate the influence of preparation design on reliability and fracture resistance of press-ceramic posterior partial-coverage restorations (PCRs) under fatigue. They compared the results for PCRs fabricated of a new press ceramic (IPS e.max Press-VP 1989/4, Ivoclar-Vivadent, Schaan, Liechtenstein) with results for ceramic inlays and unprepared molars. METHODS: The authors randomly divided 96 human upper molars into six equal groups. Control group NP specimens remained unprepared. Control group IN specimens received a mesio-occlusal-distal (MOD) inlay preparation. The test groups received PCR preparation designs based on group IN's inlay design, with additional cuspal reduction that increased from group to group. The authors fabricated 16 ceramic inlays and 64 PCRs of IPS e.max Press and luted them adhesively. All specimens underwent masticatory fatigue loading (1.2 million cycles, 1.6 hertz, 98 newtons), 5,300 thermal cycles and observation for fracture patterns. Afterward, the authors loaded all surviving specimens until fracture. RESULTS: No fractures occurred during the exposure to the masticatory simulation. After undergoing loading in a universal testing machine, the groups showed no significant differences in fracture strength values (P = .6026). Thus, the different preparation designs of the PCRs demonstrated no significant influence on the restorations' fracture resistance. The median failure loads ranged from 1,567 to 1,960 newtons. CONCLUSION: All-ceramic PCRs for molars made of IPS e.max Press were shown to be fracture-resistant, results comparable with those of natural unprepared teeth. CLINICAL IMPLICATIONS: When a posterior ceramic PCR is indicated, the clinician should perform a defect-oriented preparation that preserves tooth structure. Further clinical investigations are recommended to verify the authors' in vitro results.

Analysis of Variance↗

PubMed2005

Sinus floor elevation using osteotomes: a systematic review and meta-analysis.

BACKGROUND: Various techniques of sinus floor elevation (SFE) are described. The elevation with osteotomes (OSFE) from a crestal approach is a relatively new technique. The aim of this systematic review and meta-analysis was to evaluate the clinical outcome of implants placed into the maxillary sinus augmented with an OSFE technique. METHODS: A systematic online and manual review of the literature identified articles dealing with OSFE. Applying rigid inclusion criteria, screening and data abstraction were performed independently by two reviewers. The follow-up of loaded implants was a minimum of 6 months. The identified articles were analyzed regarding implant outcome and defined surgical aspects. Survival and success rates were estimated by Kaplan-Meier curves. RESULTS: Eight out of 44 articles dealing with osteotome sinus floor elevation met the inclusion criteria. Five of the studies met established success criteria. The survival and success rates were 95.7% and 96.0% after 24 months and 36 months, respectively. The median and mean follow-up periods were 24 and 18.73 months for the survival rate and 24 and 19.7 months for the success rate. Regarding different surgical elements, i.e., osteotome techniques, implant types, and augmentation materials, the database was multivariate. Thus, no statistical analysis could be performed on these parameters. CONCLUSIONS: Short-term clinical success/survival (<or years) of implants placed with an osteotome sinus floor elevation technique seems to be similar to that of implants conventionally placed in the partially edentulous maxilla. Controlled prospective clinical studies are needed to evaluate the long-term outcome and various surgical modifications of OSFE.

Dental Implantation, Endosseous↗

PubMed2003

Implant therapy to improve quality of life.

Excessive alveolar bone atrophy often confounds a conventional therapy with complete dentures. Implant therapy has found a way to solve the problem through enhanced stability and retention, thus increasing its functionality, leading to improved patient satisfaction and a higher quality of life. This article describes an implant-supported restoration of a patient with reduced oral health and high Oral Health Impact Profile values (OHIP-14). Upon improvement of oral hygiene and the compliance of the patient, the residual dentition was extracted and four implants were inserted, both in the maxillary and the mandibular arches. After the healing period was completed, two implant-supported prostheses with rigid bars for retention were fabricated. The patient's esthetics, phonetics, and masticatory function were properly restored at the time of delivery. A significant improvement in the patient's quality of life was noticed. In comparison to conventional dentures, the implant-supported overdentures offer better function and comfort for many patients.

Aged↗