Bruxism Research Today is a free monthly online journal that collates and summarizes the latest research about Bruxism, including details on grinding teeth, sleep, headaches, treatment. | ||||||
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Failure analysis of fractured dental zirconia implants.Gahlert M, Burtscher D, Grunert I, Kniha H, Steinhauser E Private Dental Clinic, Munich, Germany Clinical Department of Prosthetic Dentistry, Innsbruck Medical University, MZA, Innsbruck, Austria Department of Precision - and Micro-Engineering/Engineering Physics, Munich University of Applied Sciences, Munich, Germany. Objectives: The purpose of the present study was the macroscopic and microscopic failure analysis of fractured zirconia dental implants. Methods: Thirteen fractured one-piece zirconia implants (Z-Look3) out of 170 inserted implants with an average in situ period of 36.75±5.34 months (range from 20 to 56 months, median 38 months) were prepared for macroscopic and microscopic (scanning electron microscopy [SEM]) failure analysis. These 170 implants were inserted in 79 patients. The patient histories were compared with fracture incidences to identify the reasons for the failure of the implants. Results: Twelve of these fractured implants had a diameter of 3.25 mm and one implant had a diameter of 4 mm. All fractured implants were located in the anterior side of the maxilla and mandibula. The patient with the fracture of the 4 mm diameter implant was adversely affected by strong bruxism. By failure analysis (SEM), it could be demonstrated that in all cases, mechanical overloading caused the fracture of the implants. Inhomogeneities and internal defects of the ceramic material could be excluded, but notches and scratches due to sandblasting of the surface led to local stress concentrations that led to the mentioned mechanical overloading by bending loads. Conclusions: The present study identified a fracture rate of nearly 10% within a follow-up period of 36.75 months after prosthetic loading. Ninety-two per cent of the fractured implants were so-called diameter reduced implants (diameter 3.25 mm). These diameter reduced implants cannot be recommended for further clinical use. Improvement of the ceramic material and modification of the implant geometry has to be carried out to reduce the failure rate of small-sized ceramic implants. Nevertheless, due to the lack of appropriate laboratory testing, only clinical studies will demonstrate clearly whether and how far the failure rate can be reduced. To cite this article: Gahlert M, Burtscher D, Grunert I, Kniha H, Steinhauser E. Failure analysis of fractured dental zirconia implants. Clin. Oral Impl. Res. xx, 2011; 000-000 doi: 10.1111/j.1600-0501.2011.02206.x. Published 6 May 2011 in Clin Oral Implants Res. Articles on Bruxism published 27 April 2011: Education in sleep disorders in US dental schools DDS programs. Sleep Breath. INTRODUCTION: Medical school surveys of pre-doctoral curriculum hours in the somnology, the study of sleep, and its application in sleep medicine/sleep disorders (SM) show slow progress. Limited information is available regarding dentist training. This study assessed current pre-doctoral dental education in the field of somnology with the hypothesis that increased curriculum hours are being devoted to SM but that competencies are still lacking. MATERIALS AND METHODS: The 58 US dental schools ... [Abstract] [Full-text] Education in sleep disorders in US dental schools DDS programs. Sleep Breath. INTRODUCTION: Medical school surveys of pre-doctoral curriculum hours in the somnology, the study of sleep, and its application in sleep medicine/sleep disorders (SM) show slow progress. Limited information is available regarding dentist training. This study assessed current pre-doctoral dental education in the field of somnology with the hypothesis that increased curriculum hours are being devoted to SM but that competencies are still lacking. MATERIALS AND METHODS: The 58 US dental schools ... [Abstract] [Full-text] Articles on Bruxism published 18 April 2011: Impaired sleep quality and restless legs syndrome in idiopathic focal dystonia: a controlled study. J Neurol. While sleep disorders are common in Parkinson's disease and other basal ganglia disorders, information on sleep disturbances in dystonia is limited to generalized forms or Segawa disease. Although many patients with idiopathic cervical dystonia (CD) and blepharospasm (BL) report poor sleep, there are no data on frequency or interactions with well known symptoms like depression and pain. Standardized interviews and assessment instruments, clinical examinations, and self rating forms were applied ... [Abstract] [Full-text] Impaired sleep quality and restless legs syndrome in idiopathic focal dystonia: a controlled study. J Neurol. While sleep disorders are common in Parkinson's disease and other basal ganglia disorders, information on sleep disturbances in dystonia is limited to generalized forms or Segawa disease. Although many patients with idiopathic cervical dystonia (CD) and blepharospasm (BL) report poor sleep, there are no data on frequency or interactions with well known symptoms like depression and pain. Standardized interviews and assessment instruments, clinical examinations, and self rating forms were applied ... [Abstract] [Full-text] Articles on Bruxism published 14 April 2011: Influence of experimental esophageal acidification on sleep bruxism: a randomized trial. J Dent Res, 90(5): 665-71. The aim of this cross-over, randomized, single-blinded trial was to examine whether intra-esophageal acidification induces sleep bruxism (SB). Polysomnography with electromyogram (EMG) of masseter muscle, audio-video recording, and esophageal pH monitoring were performed in a sleep laboratory. Twelve healthy adult males without SB participated. Intra-esophageal infusions of 5-mL acidic solution (0.1 N HCl) or saline were administered. The frequencies of EMG bursts, rhythmic masticatory muscle ... [Abstract] [Full-text] Articles on Bruxism published 12 April 2011: Survival and success rates of immediately and early loaded implants: 12-month results from a multicentric randomized clinical study. J Oral Implantol. Abstract Objective: to compare survival and peri-implant bone levels of immediately non-occlusally versus early loaded implants in partially edentulous patients up to 12 months after implant placement.Materials and methods: Eighty patients (inclusion criteria: general good health, good oral hygiene, 30-65 years old; exclusion criteria: head and neck irradiation/cancer, pregnancy, uncontrolled diabetes, substance abuse, bruxism, lack of opposing occluding dentition, smokers >10 ... [Abstract] [Full-text] Survival and success rates of immediately and early loaded implants: 12-month results from a multicentric randomized clinical study. J Oral Implantol. Abstract Objective: to compare survival and peri-implant bone levels of immediately non-occlusally versus early loaded implants in partially edentulous patients up to 12 months after implant placement.Materials and methods: Eighty patients (inclusion criteria: general good health, good oral hygiene, 30-65 years old; exclusion criteria: head and neck irradiation/cancer, pregnancy, uncontrolled diabetes, substance abuse, bruxism, lack of opposing occluding dentition, smokers >10 ... [Abstract] [Full-text] Survival and success rates of immediately and early loaded implants: 12-month results from a multicentric randomized clinical study. J Oral Implantol. Abstract Objective: to compare survival and peri-implant bone levels of immediately non-occlusally versus early loaded implants in partially edentulous patients up to 12 months after implant placement.Materials and methods: Eighty patients (inclusion criteria: general good health, good oral hygiene, 30-65 years old; exclusion criteria: head and neck irradiation/cancer, pregnancy, uncontrolled diabetes, substance abuse, bruxism, lack of opposing occluding dentition, smokers >10 ... [Abstract] [Full-text] © 2005-2011 Bruxism Research Today. All Rights Reserved. |
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