Wim Slot

A systematic review of implant-supported maxillary overdentures after a mean observation period of at least 1 year

AIM The aim of the present systematic review of implant-supported maxillary overdentures was to assess the survival of implants, survival of maxillary overdentures and the condition of surrounding hard and soft tissues after a mean observation period of at least 1 year. MATERIAL AND METHODS MEDLINE (1950-August 2009), EMBASE (1966-August 2009) and CENTRAL (1800-August 2009) were searched to identify eligible studies. Two reviewers independently assessed the articles. RESULTS Out of 147 primarily selected articles, 31 studies fulfilled the inclusion criteria. A meta-analysis showed an implant survival rate (SR) of 98.2% per year in case of six implants and a bar anchorage. In case of four implants and a bar anchorage, the implant SR was 96.3% per person. In case of four implants and a ball anchorage, the implant SR was 95.2% per year. CONCLUSION In all three treatment options, the SR of the implants is more than 95%. The studies included reveal that a maxillary overdenture supported by six dental implants, which are connected with a bar, is the most successful treatment regarding survival of both the implants and overdenture. Second in line is the treatment option with four implants and a bar. The treatment option with four or less implants and a ball attachment system is the least successful.

Maxillary sinus floor elevation surgery with BioOss® mixed with a bone marrow concentrate or autogenous bone: test of principle on implant survival and clinical performance

The purpose of this study was to assess implant survival and 1-year clinical performance of implants placed in the posterior maxilla that had been subjected to maxillary sinus floor elevation surgery with bovine bone mineral (BioOss®) mixed with autogenous bone marrow concentrate or autogenous bone. In a randomized, controlled, split-mouth design study, a bilateral sinus floor augmentation procedure was performed in 12 edentulous patients. At random, one side was treated with BioOss® seeded with an iliac crest bone marrow concentrate enriched in mesenchymal stem cells (test side) and the other with BioOss® mixed with autogenous bone (control side). Three to four months after augmentation, 66 implants were placed. Implant survival, plaque, gingival, and bleeding indices, probing depth, and peri-implant radiographic bone levels were assessed at baseline and 12 months after functional loading. During osseointegration, three implants failed on the test side (two patients) and no implants failed on the control side, resulting in 3-month survival rates of 91% and 100%, respectively. No implants were lost after functional loading and no differences in soft tissue parameters or peri-implant bone loss were observed between the control and test sides. After 1 year in function, no clinically relevant differences were observed regarding soft tissue parameters or peri-implant bone loss.

Attachment of clips in a bar-retained maxillary implant overdenture : a clinical report

Implant-supported overdentures are a good alternative for patients with conventional dentures that lack retention and stability. The most common prosthetic complications in mandibular and maxillary implant-supported overdentures are fracture and loosening of the attachment system. This clinical report describes the treatment of a completely edentulous patient with sinus floor elevation by using bone from the iliac crest and the insertion of 4 implants in the maxilla and mandible followed by implant-supported overdentures. The technical procedure for the attachment of clips to an acrylic resin overdenture base with the use of metal reinforcement is described. The advantage of this attachment procedure is an improved attachment system with less fracture and less loosening of the clips.

Terugplaatsen van kroonfragmenten na trauma

SamenvattingEen student fiscaal recht van 26 jaar meldt zich in op een avond bij de dienstdoende tandarts. De patiënt blijkt na zich in zijn duim gesneden te hebben onwel te zijn geworden, waarbij hij met zijn kin op zijn bureaublad is terechtgekomen. Hij meldt zich bij de spoedeisende dienst waar de losse kroonfragmenten worden verwijderd en in de prullenbak worden gedeponeerd. De dienstdoende tandarts verwijst hem door naar een implantoloog voor het plaatsen van implantaten. De student vist de fragmenten uit de prullenbak, waarna een ontdekkingsreis begint langs diverse tandheelkundige specialisten.

Does a large dehiscent implant surface at placement affect the 5-year treatment outcome? An assessment of implants placed to support a maxillary overdenture

The aim of this study was to assess the 5-year clinical and radiographic outcome of implants with a dehiscent surface at implant placement. A total of 26 consecutive patients (mean age 61.6 years; SD 8.0 years) with at least one implant with a dehiscent implant surface of ≥ two thirds of the implant length on the labial side were included. All implants were placed to support a maxillary overdenture. The implants were placed with adequate primary stability and the dehiscent surface was covered with autologous bone, inorganic bovine bone and a resorbable membrane. Outcome measures were soft tissue conditions, change of radiographic marginal bone level and implant survival. Baseline data (at loading, T0) were compared with 1-year (T1) and 5-year (T5) post loading data. Of the 116 implants, 40 implants had no dehiscence, 16 had a buccal dehiscence < two thirds of the implant length, and 60 implants had a dehiscence ≥ two thirds. The peri-implant tissues were healthy and 5-year marginal bone changes were well within normal limits (-0.4 mm; range: -0.8 to -0.1). One implant was lost during the osseointegration period. Even when implants are placed with a dehiscence ≥ two thirds of the buccal implant surface, favorable 5-year peri-implant health can be achieved provided these dehiscences are covered with autologous bone, inorganic bone and a resorbable membrane, and there is good initial stability of the implants.