The importance of implant surface characteristics in the replacement of failed implants

PURPOSE: The purpose of the study was to compare the failure rates of implants with either a machined surface or a TiUnite surface used to replace failing implants. MATERIALS AND METHODS: The files of 578 patients, ie, of all patients who were treated at the Department of Periodontology of the University Hospital in Leuven by means of oral implants during 3 recent consecutive years, were analyzed. The implants included in the study had an observation time ranging from 9 to 49 months. All patients had been provided with Brånemark System implants. Only 2 types of implant surfaces were used: machined and TiUnite. Data collection and analysis focused on the replacement implants, ie, implants placed at sites where the original implants had failed. Data were statistically analyzed by means of Statistica for Windows Software version 5.1; a Fisher exact P test was used. The level of significance was set at P = .05. RESULTS: A total of 41 patients experienced the nonintegration of 58 implants. Of those, 29 implants with a machined surface were replaced by implants with the same surface. Six of the replacement implants failed. Nineteen machined-surface implants were replaced by TiUnite surface implants; 1 failed. Ten TiUnite-surface implants were replaced by implants with the same surface; none failed. The difference in failure rate between machined-surface replacement implants and TiUnite replacement implants was statistically significant (P = .05). DISCUSSION: In addition to the usual patient-related compromising factors, replacement of a failing implant involves the challenge of achieving osseointegration in a nonpristine bone site. In the present study, implants with TiUnite surfaces were associated with fewer failures than machined-surface implants under the same conditions. CONCLUSION: An improved implant surface such as TiUnite may offer a better prognosis when a failed implant has to be replaced at the same site.status: publishe

Impact of local and systemic factors on the incidence of oral implant failures, up to abutment connection

Aim: The aim of this retrospective study was to assess the influence of systemic and local bone and intra-oral factors on the occurrence of early implant failures, i.e. up to the abutment connection.status: publishe

Soft tissue augmentation of the cheeks detected on intra- and extraoral radiographs: a case report

Augmentation material used in plastic surgery such as facelift procedures can be radiopaque and thus become visible on extra- and intraoral radiographs. These objects may obscure anatomical structures and mask critical findings, therefore leading to potential misinterpretation of otherwise successful images. The present report describes a case in which the radiographic intra- and extraoral data are partly masked by a superimposed radiopaque mesh, which was suspected to originate from a facelift procedure. A gold thread lift was confirmed by the plastic surgeon.status: publishe

Impact of local and systemic factors on the incidence of late oral implant loss

Background: This retrospective study was set to assess the influence of systemic and local bone and intra-oral factors on the occurrence of implant loss from abutment connection up to 2 years.status: publishe

Microbiological and clinical outcomes and patient satisfaction for two treatment options in the edentulous lower jaw after 10 years of function

BACKGROUND: Long-term data on microbiological and clinical outcome as well as on patient satisfaction after implant therapy in the edentulous mandible are limited. Especially comparisons between fixed full prostheses (FFPs) and overdentures (ODs), or between anchoring systems for the latter are scarce. AIM: This study aimed to evaluate both of these parameters at the 10-year follow-up in a group of fully edentulous patients rehabilitated via an OD or a FFP (the latter to allow inter-group comparison). MATERIAL AND METHODS: A total of 37 fully edentulous patients (25 ODs, 12 FFPs, age at implant installation ranged from 36 to 85 years) participated in this study. All subjects received their implants (Branemark System, Nobel Biocare AB, Gothenburg, Sweden) 10 years previously. For the ODs different attachment systems (bar, magnets, ball) had been applied that allowed a further intra-group comparison. At the follow-up visit, 10 years after the abutment insertion, a series of periodontal parameters were recorded, long-cone radiographs were taken and subgingival plaque samples were collected for analysis using checkerboard DNA-DNA hybridization. The clinical and radiographic data were recorded at abutment connection and after 1 and 10 years. RESULTS: After 10 years of loading, mean plaque and bleeding indices and changes in attachment or marginal bone level were not significantly different, neither between the OD and FFP group, nor within the OD group. The marginal bone loss between abutment connection and year 10 was 0.86 and 0.73 mm for OD and FFP groups, respectively. The subgingival microbiota at implant sites from all (sub)-groups was comparable, with low numbers of DNA counts (+/-10 x 10(5)) but high detection frequencies of Actinobacillus actinomycetemcomitans (>90%), Porphyromonas gingivalis (>85%) and Tannerella forsythensis (30%). The composition of the subgingival microbiota was influenced by probing depth and bleeding tendency. Patient satisfaction was very high for both types of prosthetic rehabilitation. The FFP group scored only slightly better for chewing comfort and general satisfaction. CONCLUSION: These data indicate that from the clinical and microbiological standpoint, as well as patient satisfaction, both an OD and a FFP offer a favourable long-term outcome.status: publishe

Impact of local and systemic factors on the incidence of failures up to abutment connection with modified surface oral implants

Aim: This study aimed to assess the influence of systemic and local bone and intra-oral factors on the occurrence of early TiUnite(trade mark) implant failures. Material and Methods: A total of 283 consecutive patients (187 females; mean age 56.2), who received a total of 720 TiUnite(trade mark) implants, at the Department of Periodontology of the University Hospital of the Catholic University of Leuven, were prospectively followed. The following aspects were particularly assessed: hypertension, cardiac problems, gastric problems, osteoporosis, hypo- or hyperthyroid, hypercholesterolaemia, asthma, diabetes types I or II, Crohn's disease, rheumatoid arthritis, chemotherapy, hysterectomy and intake of medication (antidepressants, steroids, hormone replacement), radiotherapy of the concerned area, breach of sterility during surgery, implant parameters, bone (quality, quantity, dehiscence or perforation), type of edentulism, antibiotics prescription, fenestration of the implant in the sinus/nasal cavity, immediate implant placement, apical lesion detection and insertion torque. Results and Conclusion: A global failure rate of 1.9% was recorded. Owing to the very few failures, no definitive conclusion concerning statistical significance can be achieved. However, a tendency for more failures was noticed for apical lesions, vicinity with natural dentition, smoking, hormone replacement, gastric problems, Crohn's disease, diabetes I and radical hysterectomy.status: publishe

Predisposing conditions for retrograde peri-implantitis, and treatment suggestions

BACKGROUND: Recent case reports introduced the term retrograde peri-implantitis as a lesion (radiolucency) around the most apical part of an osseointegrated implant. It develops within the first months after insertion. This retrospective study aimed to find predisposing conditions for such peri-apical lesions and to evaluate treatment strategies. METHODS: All single implants (426 in the upper, 113 in the lower jaw, all Brånemark system type) placed at the department of Periodontology of the University Hospital (Catholic University Leuven) were included in this retrospective evaluation to check the incidence of retrograde peri-implantitis. Eventual predisposing factors such as patient characteristics (age, medical history), recipient site (local bone quality and quantity, cause of tooth loss), periodontal and endodontic conditions of neighboring teeth, implant characteristics (length, surface characteristics), and surgical aspects (guided bone regeneration, osseous fenestration, or dehiscency) were considered. Moreover, implants with retrograde peri-implantitis were followed longitudinally to verify their treatment outcome by means of different parameters (Periotest values (PTV), marginal bone level, radiological size of peri-apical defect). RESULTS: Seven implants in the upper (1.6%) and 3 in the lower jaw (2.7%) showed retrograde peri-implantitis, before or at abutment connection. In comparison with successful implants, such peri-apical lesions occurred preferably at sites with a history of an obvious endodontic pathology of the extracted tooth to be replaced. The incidence of retrograde peri-implantitis was significantly higher (P<0.0001) for TiUnite implants when compared with the machined implants (8/80 vs. 2/459). The machined implant surface, however, showed a higher failure rate (6.8%) than the TiUnite implants (2.5%). Failures with machined surfaces preferably occurred at extraction sites of teeth with a history of endodontic pathology or sites adjacent to teeth with an obvious endodontic pathology. No other predisposing factors could be identified. A curettage of the peri-apical lesions and the use of a bone substitute material prevented further progression of such lesions in the upper jaw (implants maintained their marginal bone and low PTV scores). A treatment in the lower jaw was less successful. CONCLUSIONS: Within the limitations of a retrospective study, these results seem to indicate that retrograde peri-implantitis is provoked by remaining scar or granulomatous tissue at the recipient site: endodontic pathology of extracted tooth (scar tissue-impacted tooth) or possible endodontic pathology from a neighboring tooth.status: publishe