Immediate Implant Placement After Removal of Maxillary Impacted Canine Teeth: A Technical Note.

Impacted maxillary canine teeth commonly occur in the general population. The traditional therapeutic approach comprises fenestration and orthodontic traction; however, if traction is not feasible or the patient refuses orthodontic treatment, an alternative solution is to remove the impacted tooth and immediately place an implant. This technical note describes a novel surgical approach to rehabilitation after impacted canine tooth removal, entailing immediate placement of a long implant in combination with regenerative materials and a barrier. Of note, this procedure preserves the apical ridge bone crest, allowing implant anchorage and primary stability to be achieved.

Localised maxillary ridge expansion with simultaneous implant placement: a case series.

The placement of implants in edentulous areas is often compromised by a thin alveolar crest, which widens the space between the two cortical bones; this offers advantages from aesthetic, biomechanical, and functional points of view. We present our results using the osteotome technique for the creation of a site for an implant, followed by immediate placement of the implant in thin edentulous maxillae, and the stability of the bony expansion over time. Twenty-three patients (six men and seventeen women) with partial edentulism associated with horizontal resorption of the ridges were treated by this technique to obtain a wider bony base for better placement of the implants. At the same time, 36 endosseous titanium implants were inserted. Three to four months later, the patients were rehabilitated with implant-supported prostheses. All implants were successfully osseointegrated and loading began after 61-197 days. All implants inserted were 4.1 mm in diameter, and between 10 and 15 mm long. All the implant-supported prostheses functioned acceptably, with no signs or symptoms such as paraesthesiae, dysaesthesiae, or pain. Within the limits of this study this technique seems to be reliable and simple with little morbidity, and rehabilitation was as good as that after other techniques such as autogenous bone grafts or guided bone regeneration. Survival and the success of implants placed were consistent with those placed in non-reconstructed bone.

Screw- vs cement-implant-retained restorations: an experimental study in the Beagle. Part 1. Screw and abutment loosening.

The causes of implant failures can be biological or mechanical. The mechanical causes include fracture of the implant, fracture of the abutment, and loosening of the abutment. Numerous studies show that abutment loosening constitutes one of the marked implant postsurgery complications requiring clinical intervention. The aim of the present study was to evaluate the incidence of the screw loosening in screwed or cemented abutments. Six adult male Beagles were used. In each dog, the first molars and 2 premolars were extracted. The sutures were removed after 7 days. After 3 months, 10 implants were placed in each dog, 5 in the right mandible and 5 in the left mandible. The abutments either were screwed in (n=30) by applying a total strength of 30 N/cm or were cemented (n=30). After 12 months, 8 (27%) loosened screws were present in screwed abutments, whereas no abutment loosening was observed in cemented abutments (P = .0001). Screwed abutments are often submitted to nonaxial loads that determine screw and abutment loosening.

A 16-year study of the microgap between 272 human titanium implants and their abutments.

A microgap has been described at the level of the implant-abutment connection. This microgap can be colonized by bacteria, and this fact could have relevance on the remodeling of the peri-implant crestal bone and on the long-term health of the peri-implant tissues. The authors report on 272 implants with screw- or cement-retained abutments retrieved from humans for different causes during a 16-year period. In the implants with screw-retained abutments, a 60-microm microgap was present at the level of implant-abutment connection. In some areas the titanium had sheared off from the surface and from the internal threads. The contact between the threads of the implant and those of the abutment was limited to a few areas. Bacteria were often present in the microgaps between implant and abutment and in the internal portion of the implants. In implants with cement-retained abutments, a 40-microm microgap was found at the level of the implant-abutment connection. No mechanical damage was observed at the level of the implant or of the abutment. All the internal voids were always completely filled by the cement. No bacteria were observed in the internal portion of the implants or at the level of the microgap. The differences in the size of the microgap between the two groups were statistically significant (P < .05). In conclusion, in screw-retained abutments the microgap can be a critical factor for colonization of bacteria, whereas in cement-retained abutments all the internal spaces were filled by cement. In these retrieved implants, the size of the microgap was markedly variable and much larger than that observed in vitro.