Original study - ZZI 02/2009

Immediate loading and immediate restoration of oral implants: indications and survival rates

E. Nkenke1, H. Schliephake2

Based on an analysis of the current literature, the aim of the study was to compare the survival rate of immediately loaded implants with implants loaded after an unloaded healing period.

The literature search was performed electronically. Medline and Embase were searched from 1966 to 2006. The keywords were dental implant, delayed loading, immediate loading, immediate restoration, mandible, maxilla, edentulous, oral implant, partially dentate and single-tooth in different combinations.

The results of the literature analysis show that there is evidence based on prospective randomised controlled clinical trials that immediate loading of dental implants yields survival rates that are comparable to those of implants which are loaded after an unloaded healing period. These results are found in the mandible as well as in the maxilla and in edentulous, partially dentate and single-tooth situations. The lowest survival rate for immediate loading was 81.2 %, found after twelve months for single-tooth situations in the maxilla. For the remaining situations the survival rate exceeded 95 % after twelve months.

The analysis of the literature shows that immediate loading is well established in implant dentistry for all indications. In the future it will be important to define valid criteria that allow safe patient selection for immediate loading.

 

Keywords: Immediate loading, immediate restoration, dental implant, unloaded healing

1 Background

In dentistry and oromaxillofacial medicine, the use of dental implants is today a firmly established method of functional masticatory rehabilitation of edentulous segments of the jaws. Success rates of over 95 % have been described with follow-up observation periods of over five years [6]. From empirical considerations, it was usually estimated that implant healing periods of three months were required in the mandible and six months in the maxilla [5]. However, the competing procedure of immediate loading of screw-retained implants soon developed in parallel with this [18, 27]. The essential information in the literature on the different indications for implant loading after an unloaded healing period, immediate loading and the additional aspect of immediate restoration was collated.

2 Definition of immediate loading and immediate restoration

Immediate loading of oral implants is defined as a situation where the superstructure is attached to the implant within 72 hours of insertion and makes occlusion contact with the antagonist [3, 14]. In immediate restoration, likewise, a superstructure is attached directly after implant insertion. However, there is as yet no occlusion contact with the opposing teeth [10]. Immediate restoration without loading is employed especially in the aesthetic area in the form of provisional restorations.

3 Possible indications for immediate loading and immediate restoration

The principle of immediate loading and immediate restoration is employed today in both the mandible and maxilla. Edentulous jaws are included in the range of indications just as readily as single-tooth gaps or partially dentate jaws with more than one missing tooth.

4 Objective of the literature analysis

The available literature on immediate loading and immediate restoration of implants in the oral and maxillofacial area was analysed in order to establish whether this procedure leads to implant survival rates that are comparable with implants loaded after conventional healing periods of three months in the mandible and six months in the maxilla. The survival rates for immediate loading and immediate restoration are shown separately for the different indications broken down in section 6.

5 Inclusion and exclusion criteria for literature references

Relevant references were examined electronically via the “PubMed” and “EMBASE” databases (keywords: dental implant, oral implant, immediate loading, immediate non-functional loading, immediate provisionalization) and manually in the following journals: British Journal of Oral and Maxillofacial Surgery, Clinical Implant Dentistry and Related Research, Clinical Oral Implants Research, Dental Clinics of North America, Deutsche Zahnärztliche Zeitschrift, Implant Dentistry, International Journal of Oral and Maxillofacial Surgery, International Journal of Periodontics & Restorative Dentistry, International Journal of Prosthodontics, Journal of Clinical Periodontology, Journal of Cranio-Maxillofacial Surgery, Journal of Oral Implantology, Journal of Oral and Maxillofacial Surgery, Journal of Periodontology, Journal of Prosthetic Dentistry, Journal of the American Dental Association, Mund-, Kiefer- und Gesichtschirurgie, Oral Surgery Oral Medicine Oral Pathology, Periodontology 2000, Scandinavian Journal of Plastic and Reconstructive Surgery, International Journal of Oral & Maxillofacial Implants and Zeitschrift für Zahnärztliche Implantologie. Studies were included in further analysis if they met the following criteria:

Clinical trial

Prospective study design

Rotationally symmetrical implants

Immediate loading and immediate restoration according to the above definition

Minimum patient number of “5“ in the test group

Follow-up period of at least twelve months

Classification of lost implants to the maxilla or mandible and to an edentulous or partially dentate situation

No use of provisional, orthodontic and malar implants

No combination of immediately loaded and conventionally healed implants under the same superstructure.

If studies combined maxillary and mandibular data or data on edentulous and partially dentate situations, these were shown separately in the literature analysis. Case reports and retrospective studies were excluded.

6 Order of immediate loading and immediate restoration in the hierarchy of evidence-based medicine

PAGE: 1 | 2 | 3 | 4 | 5