This study demonstrates the first step in validating L&Z classification. MicroCT provides objective and detailed quantitative data on bone microarchitecture. Intraosseous implant stability is mainly determined by the density of the bone. ITVs could be a good indicator of primary implant stability, whereas ISQs measurements have some limitations and should not be used alone.

The single-implant mandibular overdenture (SIMO) has been proposed as an alternative for edentulous patients who are poorly adapted to their dentures due to low retention and stability of the conventional mandibular complete denture (CD). However, there is a lack of evidence regarding the effectiveness of SIMO, which can be measured by examining patient perception of treatment effects. The aim of this systematic review was to assess the comparative results of CD and SIMO treatments using patient-reported outcome measures. A literature search was carried out in PubMed, Scopus and Cochrane Central databases. The search included studies published up to July 2017. The focus question was: 'Do single-implant mandibular overdentures improve patient-reported outcomes compared to conventional complete dentures in edentulous patients?' Eligible studies were randomised clinical trials (RCT) and prospective studies. After initial screening for eligibility and full-text analysis, 11 studies were included for data extraction and quality assessment (five parallel-group RCTs, two crossover RCTs and four prospective studies). All studies reported marked improvement in satisfaction with the dentures and quality of life measures after SIMO treatment, irrespective of variations in implant treatment protocols and retention systems. Methodological considerations revealed a lack of evidence from RCTs on the comparative effectiveness of the two treatment strategies. Hence, although available evidence suggests considerable improvement in patient-reported outcomes following the insertion of a single implant to retain a mandibular denture, further well-designed comparative studies between SIMO and CD are required to improve the level of evidence and to support the indication of SIMO treatment in routine practice.

Because of the poor agreement between measures obtained by histomorphometry and microCT, these methods should not be used interchangeably for jawbones.

No abstract

Background Retention and stabilisation of a single‐implant mandibular overdenture (SIMO) are influenced by the biomechanical properties and clinical performance of the attachment system. Purpose To compare clinical and patient‐reported outcomes following the use of two retention systems, a ball and a stud‐type Equator attachment used for SIMO. Material and Methods Eighteen fully edentulous participants were treated with a SIMO opposing to a maxillary complete denture. They received two retentive attachments (ball and Equator) in alternate periods (sequences A‐B and B‐A) and outcomes were assessed after the 1 week (initial) and 3 months (final) periods. In the final assessment, patients were also asked about their preferred retention system. Results Compared with baseline, there was an improvement in patient satisfaction using both attachments, whilst no difference was observed between initial and final periods. Similarly, no significant differences were observed when comparing the ball and Equator at the initial (P = .330) and final (P = .08) periods. The multilevel mixed‐model analysis revealed that the patients’ satisfaction was predicted only by their satisfaction with dentures before implant placement. Although no significant difference was found between attachments regarding patient preference, this may be biased by the sequence of attachment use, which suggests that a learning effect might be present in this crossover study design. Conclusion The use of a single midline implant to retain a mandibular overdenture significantly improves patient satisfaction irrespective of the attachment used, but patients’ preference for the second treatment suggested a learning effect in this study.