Removal Rates of Dental Implants Placed in Conjunction With Autologous Bone and Xenogeneic and Synthetic Alloplastic Materials in Finland Between 1994 and 2012.

PURPOSE: This study aimed to assess the use of bone augmentation materials in Finland from 1994 to 2012 by assessing removal rates of implants placed in combination with autologous bone, xenogeneic grafts, and synthetic alloplastic materials. MATERIALS AND METHODS: The National Institute for Health and Welfare in Finland granted permission to access raw data of the Finnish Dental Implant Register for implant augmentation materials and removal rates of implants placed in augmented sites from April 1994 to April 2012. RESULTS: A total of 198,538 implants were placed in Finland between 1994 and 2012 in 110,543 operations. A total of 3318 (1.7%) of the placed implants were removed during the observation period. Augmentations were performed on 20,812 (18.8%) operations during 1994-2012. The removal rates of implants placed at sites augmented with autologous bone were 2.31%, xenogeneic materials 0.91%, and synthetic alloplastic materials 2.80%. The removal rate was 1.87% when no augmentation material was used. CONCLUSIONS: The placement of dental implants in conjunction with bone augmentation materials is predictable with a low complication rate.

Microcomputed tomography-based assessment of retrieved dental implants.

PURPOSE: The aim of this study was to demonstrate the potential of microcomputed tomography (micro-CT) technology in the assessment of retrieved dental implants. Cases are presented to illustrate the value of micro-CT imaging techniques in determining possible mechanical causes for dental implant failures. MATERIALS AND METHODS: Eight retrieved dental implants were randomly selected from a pool and imaged using a micro-CT device. Source voltages (80 to 100 kV) and source-to-detector distances (65 to 70 mm) were based on signal quality requirements with an additional criterion of achieving the highest resolution with the sample entirely in the field of view in the projection plane. One additional sample was chosen for histology and tomographic imaging so that the information contained therein could be compared. RESULTS: The micro-CT images displayed high contrast between the implant, bone, and background, with negligible metal artifacts. The micro-CT technology used in this study delivered excellent images of the retrieved implants. As a result of the quality and resolution (pixel size: 5.52 to 6.15 µm) of the images, surface morphology as well as internal structures of the retrieved implants could be observed in great detail. The majority of the retrieved implants had increased wear, dents, pits, regular shallow scratches, and deep scratches in the implant-to-abutment engagement area. Furthermore, plastic deformations, microcracks, and brittle implant fractures were observed in two implants. CONCLUSION: The mechanical competence of dental implant components plays a major role in the success of implant treatment. When failures do occur, a nondestructive three-dimensional assessment of such failed implants and their components is helpful in understanding the underlying factors. Micro-CT was found to be a useful tool for the morphologic assessment of retrieved dental implants.

Antibiotic prophylaxis patterns of Finnish dentists performing dental implant surgery.

BACKGROUND: The peri-operative use of prophylactic antibiotics in clinically healthy patients undergoing dental implant surgery is very common in Finland. While antibiotics are prescribed with the hope of preventing both local and systemic complications, their application and utilization is not uniform. OBJECTIVE: The aim of this study was to assess the variation in prescribing patterns among Finnish dentists performing dental implant placement operations. This study also aimed to examine the possible relationship between early implant removal and the use of the prophylactic antibiotics in Finland. MATERIALS AND METHODS: The National Institute for Health and Welfare in Finland granted permission to access the Finnish Dental Implant Register. The peri-operative antibiotic prophylaxis prescribing patterns were assessed in a total of 110 543 dental implant placement procedures and 1038 dental implant removal operations performed in Finland between April 1994 and April 2012. RESULTS: A total of 61 different antibiotics or combinations were prescribed peri-operatively during implant placements in Finland between 1994-2012. Phenoxymethylpenicillin was the most commonly prescribed drug (72.2%). No statistically significant difference in early implant removal rates could be found between patients who had or had not received peri-operative prophylaxis. However, patients who had received peri-operative prophylaxis had statistically significant longer implant survival rates. CONCLUSION: There is a variation in antibiotic prescribing patterns among Finnish dentists placing dental implants. The results suggest that the use of prophylactic antibiotics has little effect on the prevention of primary implant surgery-related complications and, hence, success rates.

Assessment of removed dental implants in Finland from 1994 to 2012.

PURPOSE: The National Institute for Health and Welfare in Finland (THL) has maintained the Finnish Dental Implant Register since April 1994. The aim of this study was to use the Dental Implant Register to assess the influence of patient characteristics and background factors on dental implant removals in Finland from 1994 to 2012. MATERIALS AND METHODS: THL granted permission to access the Finnish Dental lmplant Register (1994 to 2012) and assess the following factors: total implant placements, total implant removals, time from implant placement to removal, implant types, implant lengths, placed and failed implants by jaw and tooth type, and patient sex and age. RESULTS: A total of 198,538 dental implants (51 different types) were placed between 1994 and 2012. A total of 3,318 (1.7%) of the placed implants were removed during the observation period. A total of 1,856 (1.8%) of the placed implants were removed from the maxilla and 1,462 (1.5%) from the mandible (P < .001). A slight difference in the sex distribution concerning implant failures (3.1% in men vs 2.3% in women) was observed. The median removal time was 247 days postoperatively (range 0 to 11,383 days), and one-third of the implants were removed within the first 142 days. Most of the placed implants were 10 mm or longer (93.3%) with 12 mm being the most commonly used length (23.9%). Shorter implants (8 mm or less) were removed more often (2.5% removal rate) than 9 mm or longer implants (1.5% removal rate). The IMZ Implant system demonstrated the highest overall removal rates (8.5%), while Brånemark Nobel Direct (0.6%) demonstrated the lowest removal rates. Of the most commonly placed implant types (together comprising 60.9% of all implants placed), the Straumann (1.2%) and the Astra Implant (1.2%) systems demonstrated equally low removal rates. CONCLUSIONS: The overall dental implant removal rates in Finland are low. Only slight differences in gender and implant position were observed.