Two or four implants for maxillary overdentures in edentulous patients: 1-year results of a randomized controlled trial.

INTRODUCTION: Maxillary implant overdenture therapy is a good treatment option for treating patients experiencing problems with their conventional maxillary denture. Retaining the overdenture with four implants and a bar attachment system serves as the current gold standard. However, there is a demand for less costly and less invasive treatment options. The aim of this randomized controlled trial was to compare marginal bone level change (MBLC), implant and overdenture survival, clinical, masticatory, and patient-related outcomes (PROMs) of maxillary implant overdentures with either two or four implants and a bar attachment system. MATERIALS AND METHODS: Forty edentulous participants were randomly allocated to two groups (n = 20), to receive either two or four implants in the maxilla. After healing, all the participants received an implant overdenture retained by a bar attachment system. All the participants were evaluated 1 and 12 months after overdenture placement. The primary outcome was MBLC. Secondary outcomes were implant and overdenture survival, clinical, masticatory, and PROMs. The outcomes were analyzed using parametric and non-parametric tests. RESULTS: MBLC was -0.03 mm in the 2-implant group and -0.16 mm in the 4-implant group (p = 0.21). Implant survival was 83.3% in the 2-implant group and 94.4% in the 4-implant group (p = 0.03). The median pocket depth change and clinical outcomes were low, and masticatory performance along with PROMs improved in both groups and did not differ significantly between them. CONCLUSION: Maxillary 4-implant overdentures perform better than maxillary 2-implant overdentures with a bar attachment system in terms of implant and overdenture survival and therefore remains the gold standard. However, both overdentures perform similarly in terms of MBLC, clinical, masticatory, and PROMs.

Maxillary implant overdentures retained with bars or solitary attachments: A 5-year randomised controlled trial.

Purpose To compare the 5-year follow-up outcomes of maxillary overdentures retained by bars or solitary attachments.Methods Fifty consecutively selected fully edentulous patients experiencing problems with their conventional denture received four implants and were randomly allocated to receive a maxillary overdenture with either bar- or solitary attachment retention. Marginal bone level change (primary outcome), implant- and overdenture survival rate, clinical- and patient related outcome measures were recorded at baseline, and after 1 and 5 years. Biological and technical complications were recorded throughout the entire follow-up period.Results After 5 years, the mean marginal bone level change was higher in the solitary attachment group (-1.41±1.38mm, P=0.024) than in the bar group (-0.99±0.96mm). Also, fewer implants survived in the solitary attachment group (89.5%, P=0.027) than in the bar group (96.3%). The overdenture survival rate was 95.0% and 91.3% in the bar and solitary attachment group, respectively. Although the clinical and patient related outcomes were favourable and did not differ significantly between the groups, the peri-implantitis incidence was 25.8% in the solitary attachment group and 5.1% in the bar group. Any technical complications were minor.Conclusions In maxillary 4-implant overdenture therapy, the marginal bone level, implant survival rate and the number of complications are better with bar attachments than with solitary attachments. Both groups' clinical and patient related outcome measure scores were equal throughout the entire follow-up period.

The performance of two-implant overdentures in the atrophic maxilla: a case series with 1-year follow-up.

PURPOSE: To assess the implant and prosthesis survival rates, the clinical, radiographical and patient-related outcome measures, and the masticatory performance of maxillary overdentures supported by two implants in patients with an atrophic maxilla. METHODS: In this case series, 15 consecutive patients who were eligible for maxillary implant overdenture therapy, but who had insufficient bone volume to place at least four implants and were unwilling to be treated with reconstructive surgery were asked to participate. After giving consent, participants received two implants in the maxilla under local anaesthesia. After 3 months of osseointegration, a maxillary overdenture with palatal coverage and solitary attachments was fabricated. Implant and overdenture survival, marginal bone level change, clinical outcome measures, masticatory performance and patient-related outcomes were evaluated at baseline and 1 year after overdenture placement. RESULTS: Fourteen out of 15 participants completed the follow-up period of 12 months. Implant and overdenture survival rate were 89.3% and 85.7%, respectively. Change in marginal bone level (- 0.5 ± 0.7 mm), change in probing depth (0.0 ± 1.0 mm), and clinical outcomes were favourable. Masticatory performance and patient-related outcomes improved significantly compared to baseline. Complications were minimal. CONCLUSIONS: Within the limitations of this study, it can be concluded that patients with extreme resorption of the maxilla that are unwilling to be treated with reconstructive surgery, benefit from two-implant maxillary overdentures retained by solitary attachments in terms of improved masticatory functioning and denture satisfaction. However, they have relatively high risk of implant loss. TRIAL REGISTRATION: UMCG Trial Register (RR201900060), registered 22 January 2019.

Incidence of peri-implant mucositis and peri-implantitis in patients with a maxillary overdenture: A sub-analysis of two prospective studies with a 10-year follow-up period.

BACKGROUND: Though studies on maxillary overdentures show satisfying results on implant survival, patient-related outcomes and prosthetic complications, the epidemiology of peri-implant diseases in this specific group of patients has hardly been reported. While the general patient-level prevalence of peri-implant mucositis and peri-implantitis are estimated at ~45% and ~20%, respectively, the risk of developing these diseases within a specific period is less clear. To fully appreciate the epidemiology of peri-implant diseases, more long-term data on incidence of peri-implant diseases are needed. PURPOSE: The purpose of this sub-analysis of two prospective studies was to assess the incidence of peri-implant mucositis and peri-implantitis in fully edentulous patients with implant-retained maxillary overdentures during a 10-year follow-up period. MATERIALS AND METHODS: One hundred and sixteen patients treated with implant-supported maxillary overdentures were available from two clinical trials. Data on biological complications, clinical and radiographical parameters were collected for 106 patients at 5-year, for 82 patients at 10-year follow-up. The incidence was calculated following the consensus of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. Extent and severity then were calculated to enable an appropriate epidemiological description of peri-implantitis. RESULTS: The patient-level incidence of peri-implant mucositis was 37.7% after 5 years and 64.6% after 10 years whereas the patient-level incidence of peri-implantitis was 10.4% after 5 years and 19.5% after 10 years. After 10 years, the extent of peri-implant mucositis and peri-implantitis is 52.8% and 43.8%, respectively. In terms of severity, 26.5% of all affected implants suffered from >3 mm bone loss and 17.6% of all affected implants was lost. CONCLUSION: Three of five fully edentulous patients with implant-supported maxillary overdentures experience peri-implant mucositis after 10 years. Peri-implantitis occurs in one of five patients after 10 years. In spite of these incidence rates, implant survival remains high.

Utilising the nasal aperture for template stabilisation for guided surgery in the atrophic maxilla.

BACKGROUND: Templates aim to facilitate implant placement in the prosthetically preferred position. Mucosa-supported and bone-supported templates are commonly used in the edentulous maxilla. In the atrophic maxilla (Cawood V and VI), however, these templates can be easily displaced due to a lack of supportive tissues, even in cases where anterior sites offer sufficient bone for implant placement. To assist in positioning and stabilisation, we designed a template that utilises the nasal aperture as a fulcrum to create a forced and exclusive fit. The aim of this study was to assess the clinical usability of the developed template and the corresponding implant placement accuracy in patients with edentulous atrophic maxillae. Deviations between planned and placed implant positions were measured by aligning pre- and post-operative cone beam computed tomography scans. RESULTS: Twenty-four implants were placed in 11 patients. One template did not fit properly due to a slight undercut. All implants could be placed with good primary stability. The implants had high accuracy at the implant shoulder (global deviation 1.1 ± 0.5 mm, lateral deviation 0.8 ± 0.5 mm) and a mean angular deviation of 7.2 ± 3.4°. CONCLUSIONS: The developed surgical template offers stabilised and secure template placement in the edentulous atrophic maxilla, resulting in satisfying implant placement accuracy when using a semi-guided approach. TRIAL REGISTRATION: Netherlands Trial Register, NL6561, registered 26 September 2017.

Long-term effectiveness of maxillary sinus floor augmentation: A systematic review and meta-analysis.

AIM: To assess the long-term effectiveness (≥5 years) of maxillary sinus floor augmentation (MSFA) procedures applying the lateral window technique and to determine possible differences in outcome between simultaneous and delayed implant placement, partially and fully edentulous patients and grafting procedures. MATERIALS AND METHODS: MEDLINE (1950-May 2018), EMBASE (1966-May 2018) and Cochrane Central Register of Controlled Trials (1800-May 2018) were searched. Inclusion criteria were prospective studies with follow-up ≥5 years and a residual bone height ≤6 mm. Outcome measures included implant loss, peri-implant bone level change, suprastructure survival, patient-reported outcome measures and overall complications. Data were pooled and analysed using a random effects model. RESULTS: Out of 2,873 selected articles, 11 studies fulfilled all inclusion criteria. Meta-analysis revealed a weighted annual implant loss of 0.43% (95% CI: 0.37%-0.49%). Meta-regression analysis did not reveal significant differences in implant loss neither between edentulous and dentate patients nor implants placed simultaneously with or delayed after MSFA, nor implants placed in MSFA using solely autologous bone or bone substitutes. The results of the other outcome measures were favourable, and overall complications were low. CONCLUSION: MSFA is a reliable procedure in the partially and fully edentulous maxilla for support of dental implants.

Attitudes among dentists and dental hygienists towards extended scope and independent practice of dental hygienists.

AIMS: Attitudes of dentists and dental hygienists towards extended scope and independent dental hygiene practice are described in several studies, but the results are heterogenous. The purpose of this systematic review was to compare the attitudes of dentists and dental hygienists towards extended scope and independent dental hygiene practice. METHODS: PubMed, AMED and CINAHL were screened by two independent assessors to identify relevant studies. Only quantitative studies that reported the percentages of dentists' and dental hygienists' attitude towards extended scope and independent dental hygiene practice were included. The random-effects model was used to synthesise possible heterogenous influences. RESULTS: Meta proportions with regard to a positive attitude towards extended scope of practice are 0.54 for dentists and 0.81 for dental hygienists. Meta proportions of a positive attitude towards independent practice are 0.14 for dentists and 0.59 for dental hygienists. A meta analysis with regard to negative attitudes could only be performed on extended scope of practice and did not reveal a difference between the two professions. We obtained homogeneous outcomes of the studies included regarding negative attitudes of dentists . A minority of dentists hold negative attitudes towards extended scope of dental hygiene practice. Study outcomes regarding negative attitudes of dental hygienists were heterogeneous. CONCLUSIONS: Positive attitudes are present among a majority of dentists and dental hygienists with regard to extended scope of dental hygiene practice, while for independent dental hygiene practice this holds for a minority of dentists and a majority of dental hygienists.