DZZ | Deutsche Zahnärztliche Zeitschrift • October 2014

Failure analysis of mini dental implants used for complete dentures stabilization

Prof. Dr. Torsten Mundt Center for Dental, Oral and Maxillofacial Surgery Greifswald Polyclinic for dental prosthetics and materials science University Medical Center, Reiner Biffar University of Greifswald · Department of Prosthodontics, Geriatric Dentistry and Medical Materials Science, Friedhelm Heinemann University of Greifswald · Department of Prosthodontics, Geriatric Dentistry and Medical Materials Science, T. Stark, Christian Schwahn

Introduction: The aim of this study was to analyse possible factors for the loss of mini-implants with diameters between 1.8 and 2.4 mm used in the stabilization of complete dentures.

Methods: A total of 79 women and 54 men (mean age of 71.2 ± 9.8 years) were examined and interviewed in 9 dental practices. The patient records were evaluated retrospectively.
The cumulative implant survival rates were depicted with Kaplan- Meier curves and the potential risk factors were evaluated using Cox regression analyses (P < 0.05). Results: Out of 336 mini-implants in 54 maxillae 15 were lost and out of 402 mini dental implants in 95 mandibles 11 were lost due to the lack of or loss of osseointegration. Furthermore, 2 mini-implants fractured during insertion and two more were fractured after 4 and 32 months. The 4-year implant survival rate was 95.4 % in the anterior maxilla, 91.8 % in the posterior maxilla, 97.0 % in the anterior mandible and 91.1 % in the posterior mandible. Without including the fractured mandibular implants, the 4-year survival rate was 97.6 % in the anterior mandible and 95.1 % in the posterior mandible. Significant differences were found between anterior and posterior placement areas (P = 0.039) but not between the jaws (P = 0.188). The survival rate of mini dental implants with a length of 10 mm was lower than the survival rate of longer implants (90.7 % versus > 95 %, P = 0.044). The factors sex, age, and smoking habits were not significant. In the Cox regression analysis, neither the placement area nor the implant length showed a significant Hazard ratio after adjustment.

Conclusion: The 4-year survival rates of mini-implants used in the stabilization of complete dentures were acceptable in both jaws. The failures tended to be more frequent in the posterior area and for shorter implants.

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ZMK • Juli/August 2014

Mini dental implants? Sure!

Dr. Kai D. Haschemian

Especially in atrophied mandibles, where conventional diameter implants meet their limits, mini dental implants can be a sensible solution.
This is also true in patients, where an invasive procedure can pose medical risks. Thanks to the diameters of mini dental implants, which are less than
3 mm, cases where the mandible is very thin, the MDIs can be placed with a minimal invasive procedure that often does not require bone augmentation.
The most common indication for the mini dental implants in our practice is for the stabilization of the full denture in the lower jaw. Edentulism is a disability that may even result in the higher mortality of the patient. A prosthesis, which is solely supported by the gingival tissue does not provide an adequate replacement of the missing dentition: especially in the case of the atrophied jaw where the retention is especially low. This compromised situation can result in the avoidance of social situations as well as malnutrition due to food restrictions. Through implant therapy, it is possible to stabilize the prosthesis and thus substantially increase the patient’s quality of life.
Unfortunately, a conventional implant therapy does not come into question for many patients. Especially with senior citizens with medical risk factors there would be large concerns about a heavy surgical procedure where a bone augmentation might be required. Additionally the cost factor plays a large role with many patients. Here mini dental implants offer a cost effective and minimal invasive alternative that is acceptable for many patients.

Dental Magazin • August 2014

MINIS (Mini Dental Implant): ACCEPTANCE IS GROWING

Dr. Norbert Enkling

Although accepted in the dental practice, mini dental implant had long been seen with skepticism. But in the last years mini dental implants have attracted the attention of academics and researchers and have been followed up with studies from many different universities around the world. Whereas there were initial fears about the survival rates and risks of fractures on mini implants, the studies have shown that the survival rates of mini dental implants are actually quite similar to those of conventional implants. These studies, till now have mostly addressed the main indication of the mini dental implants, that of stabilizing the full prosthesis in the edentulous mandible.

Dental Magazin • August 2014

Minimal invasive, cost effective alternative

Prof. Dr. Torsten Mundt Center for Dental, Oral and Maxillofacial Surgery Greifswald Polyclinic for dental prosthetics and materials science University Medical Center

The 4 year survival rates of mini dental implants used in the stabilization of the full prosthesis stand at 95% success or higher. Will mini dental implants establish themselves as a viable therapy for compromised bone volume? Interest in mini dental implants is increasing. Research and studies on MDIs is also increasing, but despite this trend skepticism remains.

Implantologie Journal • January 2014

Mini Dental Implants Used as Strategic Support for the Retention of Partial Dentures

Dr. Friedhelm Heinemann University of Greifswald · Department of Prosthodontics, Geriatric Dentistry and Medical Materials Science, Dr. Christoph Bourauel University of Bonn | Uni Bonn · Zentrum für Zahn-, Mund,- und Kieferheilkunde, Dr. Istabrak Hasan, M.Sc. B.D.S., Prof. Dr. Torsten Mundt Center for Dental, Oral and Maxillofacial Surgery Greifswald Polyclinic for dental prosthetics and materials science University Medical Center

Partial dentures supported on natural teeth are a standards in dentistry and are used on a significant percentage in the prosthetic cases in the German population. In the future, with the improvement of dental hygiene in the population there will be less total edentulism but instead there will be an increase in the cases of partial edentulism and consequently there will be an increase in partial bridges.
Mini dental implants offer a viable alternative to natural tooth and conventional implant supported partial bridges. When using mini dental implants in this role it is important that certain guidelines are followed in order to achieve long term success

Dent Implantol • 2013

Investigation of peri-implant tissue conditions and peri-implant tissue stability in implants placed with simultaneous augmentation procedure: a 3-year retrospective follow-up analysis of a newly developed bone level implant system

Dr. Winfried Walzer

From the point of view of esthetics and cost, dentures are seen as acceptable but when it comes to functionality and comfort though, the solutions are quite limited. The reason for this may be that for many patients, the high cost of treatment as well as the trauma involved make it impossible. Now, thanks to the clinically proven worthiness of mini dental implants, it is possible to treat a larger percentage of patients in a quick and cost effective way that provides a functional solution with a secure retention of the prosthesis. The MDI, mini dental implants with diameters of 1,8 / 2,4 and 2,9 through a minimal invasive protocol are able to stabilize full and partial prosthesis.

Dent Implantol • 2013

Systematic Approach to the Insertion of Mini Dental Implants as Additional Support

Dr. Jochen Hilgert

Mini implants have been available in Germany for over ten years.
Mini dental implants have been approved for long term use and now are used in the millions.
In my practice in Drensteinfurt, i have been using mini dental implants, MDIs, since 2001 in cases of the stabilization of the full prosthesis. and since 2003 I have used mini dental implants for the support of partial dentures.
After the indication of stabilization of the full prosthesis, surely the second biggest
potential for mini dental implants lies in the support of partial dentures.

 

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DZW • December 2012

Multiple abutments with mini-implants
Extended indication for the stabilization of partial dentures

Dr. Jochen Hilgert

Since their introduction into the German market in 2001, MDIs, mini dental implants have proven themselves as  a viable solution for the stabilization of the full prosthesis. But following his presentation to the 2nd MDI user symposium in 2011, Dr. Jochen Hilgert, has proven that based on clinical studies,  MDI is also a  real  solution to the stabilization of the partial prosthesis. Dr Hilgert presented a statistical analysis of the study covering his eight years and 525 mini dental implants. Of the 525 mini dental implants that he set, 75% were in combination with telescopes prosthesis and only 20% of the MDIs were used for stabilizing the full prosthesis.