International journal of oral implantology (Berlin, Germany)最新文献

Aims: Immediate fixed full-arch implant-supported prosthetic rehabilitation of the severely atrophic maxilla is a challenging treatment modality with favourable patient interest. The delivery of the treatment is challenging due to the difficulty in providing adequate posterior implant positioning with high primary stability in the absence of alveolar bone distal to the maxillary lateral incisors. Current trends in posterior implant placement and immediate loading include the placement of zygomatic implants or distally tilted implants placed anterior to the sinus cavity. The development of an extended-length subcrestal angulated implant gives an additional option to provide posterior occlusal support for reconstruction of the severely atrophic maxilla with an immediate full-arch fixed prosthesis.

Materials and methods: This article describes a trans-sinus nasal protocol for fixed full-arch rehabilitation in the severely atrophic maxilla when the residual alveolar bone does not extend distally from the permanent maxillary lateral incisors. The extended-length distally tilted implant transverses a simultaneously augmented sinus cavity and engages the anterior maxilla and bone of the lateral nasal wall.

Results: The placement of an extended-length distal tilted implant placed the implant head at the crest of the alveolar ridge in the first permanent molar position, promoting favourable prosthetic biomechanics for a full-arch fixed prosthesis. Passivity of fit of the fixed prosthesis was achieved due to the 24-degree subcrestal angulation feature of the implant and use of multi-unit abutments.

Purpose: To evaluate whether the use of piezoelectric bone surgery (PBS) for implant site preparation reduces surgical time, improves implant stability, preserves marginal bone level and improves the survival rate of oral implants compared with conventional drilling techniques.

Materials and methods: This meta-analysis followed the PRISMA (preferred reporting items for systematic review and meta-analysis) guidelines and was registered in the PROSPERO (international prospective register of systematic reviews) database (CRD42019142749). The PubMed, Embase, Scopus and Open Grey databases were screened for articles published from 1 January 1990 to 31 December 2018. The selection criteria included randomised controlled trials (RCTs) and case-control studies (CCTs) comparing the PBS with conventional rotary instruments for implant site preparation, and reporting any of the selected clinical outcomes (surgical time, implant stability, marginal bone variations and implant failure rate) for both groups. The risk of bias assessment was performed using the Cochrane Collaboration tool for RCTs and the Newcastle-Ottawa scale (NOS) for CCTs. A meta-analysis was performed, and the power of the meta-analytic findings was assessed by trial sequential analysis (TSA).

Results: Eight RCTs and one CCT met the inclusion criteria and were included in the review. The meta-analysis and the TSA showed moderate evidence suggesting that the PBS prolongs surgery duration and improves secondary stability 12 weeks after implant placement compared with conventional drilling techniques. Insufficient data are available in literature to assess if the PBS reduces marginal bone loss and/or improves the implant survival rate compared with conventional drilling techniques.

Conclusions: Adequately powered randomised clinical trials are needed to confirm the PBS positive effect on the secondary stability and to draw conclusions about the influence of PBS on marginal bone stability and implant survival.

Purpose: To assess the technical and biological complications of screw- and cement-retained implant-supported full-arch dental prostheses.

Materials and methods: An electronic search was conducted on Medline/PubMed and Cochrane databases in February 2019; irrespective of any time restrictions using MeSH terms. All studies were first reviewed by abstract and subsequently by full-text reading. Further hand search was performed to identify other related references. Articles only related to cement-retained and/or screw-retained reconstructions in full-arch fixed dental prostheses (FDP) were included.

Results: The initial literature search resulted in 3670 papers. 3478 articles remained after removing duplicate articles, and 3439 articles were further excluded by the reviewers after the abstract screening, which resulted in a selection of 39 studies. 12 studies were further excluded due to not fulfilling the inclusion criteria. Hand searching resulted in two additional papers being included, and finally, 29 articles were included in this review. Screw-retained full-arch fixed dental prostheses have fewer complications than cemented reconstructions. Biological complications such as marginal bone loss > 2 mm occurred more frequently in cemented reconstructions, and technical complications such as screw-loosening and screw fracture occurred more in screw-retained reconstructions.

Conclusion: Cemented reconstructions exhibited more biological complications (implant loss, bone loss > 2 mm) and screw-retained prostheses exhibited more technical problems. Clinical outcomes were influenced by both fixations in different ways. The screw-retained restorations were more easily retrievable than cemented ones, therefore, technical and eventually biological complications could be treated more easily. For this reason, and for their higher biological compatibility, these reconstructions are preferable.

Purpose: To describe implant survival at least 1 year after the surgical treatment of early apical peri-implantitis (EAP) and explore potential risk factors of failure of such treatment.

Materials and methods: An ambispective cohort study was conducted, involving all patients in whom EAP was detected and surgically treated between 1996 and 2016. Reporting followed the STROBE guidelines. The time from implant placement (IP) to EAP surgery (EAPS), the diagnostic stage and intraoperative variables (location, apical lesion in the tooth being replaced, mesial and distal tooth-implant distance measured at the apex, periapical surgery of the adjacent tooth, guided bone regeneration, implant resection, explantation) were recorded to determine their impact upon treatment outcome.

Results: The initial sample consisted of 58 implants in 46 patients. The mean time from IP to EAPS was 21.7 ± 10.1 days. At the time of surgery, eight implants presented mobility and were explanted. The final sample consisted of 50 implants in 39 patients evaluated for implant survival after surgical treatment. A cumulative survival rate of 78.3% was recorded. The mean survival time of the EAP treated implants was 85.4 months (standard deviation [SD] 5.94). The diagnostic stage (P < 0.001) and the existence of a previous periapical lesion in the tooth being replaced (P = 0.022) had a significant influence upon implant survival.

Conclusions: The cumulative survival rate was 78.3%, with a mean survival time of 85.4 months. The diagnostic stage of EAP and the presence of a lesion in the tooth being replaced significantly influenced the survival of implants with EAP subjected to surgical treatment.

Purpose: The aim of this study was to estimate bleeding prevalence and postoperative peri-oral purpura after full-arch immediate implant rehabilitation according to the 'All-on-four' technique, in patients on different oral anticoagulant therapies (warfarin and rivaroxaban).

Materials and methods: A total of 120 patients (47 women, 73 men, mean age 66.4 years) presented with edentulous or partially edentulous arches. All patients were treated with immediate full-arch fixed prostheses (28 maxillary, 34 mandibular), each supported by four implants (two vertical, two distally tilted). Participants were divided in three groups: 40 patients under treatment with warfarin formed group A, 40 patients under treatment with rivaroxaban composed group B, and 40 healthy subjects composed the control group. As the primary outcome measure, mild, moderate and severe postoperative bleeding was recorded. As the secondary outcome measure, the presence of postoperative petechiae, ecchymoses and haematomas in oral and peri-oral tissues was recorded.

Results: Patients under treatment with warfarin (group A) showed a higher prevalence of postoperative bleeding (P = 0.002) and purpura (P = 0.012) in comparison with other groups. No severe bleeding took place and no haematomas appeared in any patient. Prefabricated metal-reinforced, screw-retained, acrylic resin provisional restorations were delivered in all patients.

Conclusions: The preliminary results of this prospective case-control study showed how immediate rehabilitation according the 'All-on-four' technique could be a safe and predictable procedure in anticoagulated patients where anticoagulation therapy is not discontinued or modified.

Purpose: The purpose of this study was to evaluate the 2-year outcomes of the one-tooth onetime complete digital workflow, allowing the immediate loading of a single implant in the posterior region with a final CAD/CAM crown made of a polymer-infiltrated ceramic network.Materials and methods: A series of 10 implants were placed, and an intraoral scan was taken after surgery. A final screw-retained polymer-infiltrated ceramic network crown was manufactured chairside and placed the same day in full occlusion. Marginal peri-implant bone changes and soft tissue health were evaluated, and restoration performance was assessed using FDI World Dental Federation criteria and pink and white aesthetic scores. Patient-reported outcome measures and data on the time required to perform the procedures were collected.Results: After 2 years, the implant survival rate was 100%. The debonding of one crown from its titanium base led to prosthodontic survival rate of 90% and the remaining crowns were all considered successful. The mean marginal peri-implant bone changes yielded 0.87 mm (standard deviation 0.96 mm) and 0.55 mm (standard deviation 0.53 mm) after 1 and 2 years, respectively. Mild or no inflammation of peri-implant soft tissue was observed in most implants. The total treatment time was 175 minutes and patient-reported outcome measures displayed high patient satisfaction.Conclusions: This study constitutes the first report examining immediate loading of a single implant in the posterior region with a final crown in occlusion. In this case series, the 2-year outcomes of the one-tooth one-time protocol seem rather promising and fulfilled patient expectations. However, these preliminary results need to be confirmed by randomised controlled trials, and patient selection is likely to be a key factor in the success of this procedure.

Aims: While numerous materials are available for sinus floor elevation, plant-based alternatives still hold promise of overcoming concerns about allogeneic or xenogeneic materials. Thus, the present authors designed a randomised clinical trial to histologically compare an almost pure hydroxyapatite (HA) to a biphasic calcium phosphate comprising 80% β-tricalcium phosphate (β-TCP) and 20% hydroxyapatite (β-TCP/HA), all of phycogenic origin.Materials and methods: Twenty patients scheduled for lateral window sinus floor elevation were randomised to either an HA or a β-TCP/HA group. Biopsy specimens were taken 3 months after sinus floor elevation and during implant surgery after 6 months. One ground section per biopsy specimen (N = 40) was stained, scanned and histomorphometrically analysed for new bone, old bone, soft tissue, graft, bone infiltration of graft, bone-to-graft contact and penetration depth.Results: At 6 months, more new bone was seen in the β-TCP/HA group (P = 0.011), whereas more residual graft was present and in more extensive contact with new bone in the HA group. More pronounced alterations, and smaller particle sizes, of graft surrounded and infiltrated by bone were seen in the β-TCP/HA group. The less extensive bone-to-graft contact in the β-TCP/ HA group reflected a more advanced state of resorption, while infiltration of residual graft material by bone was also increased in this group.Conclusions: Proper healing was seen in both groups, with the graft materials guiding the formation of new bone, which grew especially well through the particles of the highly osteoconductive and resorptive β-TCP/HA material. HA was very stable, without significant resorption, but was extensively in contact with new bone after 6 months.

Purpose: To assess the effectiveness of different nonsurgical protocols for the treatment of peri-implant mucositis.

Materials and methods: The identification of randomised clinical trials (RCTs) was systematically performed in three databases and supplemented by a thorough manual search of the literature in periodontics/implantology-related journals. Studies investigating the effect of mechanical and/or chemical plaque control agents aimed at preventing the development of peri-implant mucositis were excluded. When comparable trials were found, a meta-analysis was performed.

Results: Fourteen studies were included in the systematic review and three in the meta-analysis. None of the selected studies reported a complete resolution of the peri-implant mucositis lesions. A nonsurgical therapy alone showed an average reduction of: 0.57 mm (95% CI [0.30 to 0.83]) in probing pocket depth (PPD); 22.41% (95% CI [12.74 to 32.08]) in bleeding on probing (BOP); 17.28% (95% CI [3.99 to 30.58]) in the plaque index (PI); and 13.41% (95% CI [3.50 to 23.31]) in the bleeding index (BI). The meta-analysis failed to demonstrate significant improvements with the adjunct use of chlorhexidine disinfectant to nonsurgical mechanical debridement for PPD reduction (-0.07 mm; 95% CI [-0.33 to 1.15], P = 0.62), and relative attachment level (RAL) gain (-0.13 mm; 95% CI [-0.6 to 0.35]), P = 0.6).

Conclusion: Conventional nonsurgical mechanical therapy alone may be considered the standard treatment for peri-implant mucositis as there is still a lack of evidence supporting the use of additional chemical/mechanical agents for clinical and/or microbiological improvement.

Purpose: The present study aimed to identify the systemic risk indicators associated with peri-implant mucositis and peri-implantitis in individuals with implant-supported fixed prostheses.

Materials and methods: In this cross-sectional study, clinical evaluations of periodontal and peri-implant conditions were performed by a single examiner in a sample of 71 volunteers with 360 implants. Peri-implant mucositis was defined as the occurrence of bleeding on probing in association with redness and swelling or suppuration, without bone loss. Peri-implantitis was defined based on a radiograph of bone loss ≥ 3 mm and/or a probing depth ≥ 6 mm with bleeding and/or suppuration on probing. The systemic factors evaluated were obesity, hormone replacement therapy, osteopaenia and osteoporosis, high blood pressure and hypercholesterolaemia. Logistic models were applied to assess the associations between peri-implant diseases and systemic factors.

Results: Mucositis and peri-implantitis were found in 83.1% and 16.9% of the individuals, respectively. The regression analysis showed that obesity (prevalence ratio = 5.23; 95% confidence interval, 1.91 to 96.83; P = 0.01) and high systolic blood pressure (prevalence ratio = 4.23; 95% confidence interval, 1.66 to 12.87; P = 0.03) were associated with peri-implantitis at the individual and implant levels, respectively. No systemic factor was associated with peri-implant mucositis (P ≥ 0.06).

Conclusion: Obesity and high systolic blood pressure were associated with peri-implantitis, whereas no systemic factor was associated with peri-implant mucositis. Future prospective studies are required to confirm these as true risk factors. Patients with obesity and/or high systolic blood pressure could be informed of the likely association with peri-implantitis, preferably before implant placement.

Purpose: This long-term cohort study investigated the prevalence of mucositis, peri-implantitis, bone loss and survival of turned surface implants in partially edentulous patients treated for periodontitis.

Materials and methods: 19 patients treated for generalised chronic periodontitis (GCP) and 20 patients treated for generalised aggressive periodontitis (GAP) were orally rehabilitated with a total of 126 dental implants. Examinations were performed before implant insertion, at the time of superstructure insertion, and in the subsequent years during a 3-month recall schedule over a 10- to 20-year period. At every session, clinical parameters were recorded. Intraoral radiographs were taken after insertion of superstructures and 1, 3, 5, 10, 15 and 20 years later.

Results: In total, nine implants were lost during the 20-year observation period. The implant survival rate was 92.1% (GCP patients) and 90.1% (GAP patients). After 10 years, mucositis was present in 21.9% and 21.2% of implants in GCP and GAP patients, respectively. The risk of mucositis was significantly lower in patients with a removable superstructure (OR = 0.061 with P = 0.001). Peri-implantitis was present in 12.2% implants (GCP patients) and 14.1% implants (GAP patients). Implants inserted in bone quality grade 3 showed a significantly higher risk of peri-implantitis (OR = 5.658 with P = 0.003). After 10 years, implants in GAP patients did not show a significant higher bone loss (1.87 ± 1.40 mm) compared with implants in GCP patients (1.50 ± 1.30 mm). After 20 years, the total mean peri-implant bone loss was 1.98 ± 1.64 mm, almost every fifth implant revealed a bone loss > 3 mm.

Conclusions: The implant survival rate in both patient groups was > 90%, and implants showed a moderate mucositis (< 30%) and peri-implantitis (< 25%) rate. Bone quality and type of superstructure seem to have had an influence on peri-implant health. These results suggest that patients with a history of periodontitis treated in a tight recall schedule can be successfully rehabilitated with turned surface implants for a follow-up period of 10 to 20 years.