Effects of immediate and delayed loading protocols on marginal bone loss around implants in unsplinted mandibular implant-retained overdentures: A systematic review and meta-analysis
Background: Immediate loading has recently been introduced into unsplinted mandibular implant-retained overdentures for the management of edentulous patients due to their increasing demand on immediate aesthetics and function. However, there is still a scarcity of meta-analytical evidence on the efficacy of immediate loading compared to delayed loading in unsplinted mandibular implant-retained overdentures. The purpose of this study was to compare the marginal bone loss (MBL) around implants between immediate and delayed loading of unsplinted mandibular implant-retained overdentures.
Methods: Randomized controlled trials (RCTs), controlled clinical trials (CCTs), and cohort studies quantitatively comparing the MBL around implants between immediate loading protocol (ILP) and delayed loading protocol (DLP) of unsplinted mandibular overdentures were included. A systematic search was carried out in PubMed, EMBASE, and CENTRAL databases on December 02, 2020. “Grey” literature was also searched. A meta-analysis was conducted to compare the pooled MBL of two different loading protocols of unsplinted mandibular overdentures through weighted mean differences (WMDs) with 95% confidence intervals (95% CIs). The subgroup analysis was performed between different attachment types (i.e. Locator attachment vs. ball anchor). The risk of bias within and across studies were assessed using the Cochrane Collaboration’s tool, the Newcastle-Ottawa scale, and Egger’s test.
Results: Of 328 records, five RCTs and two cohort studies were included and evaluated, which totally contained 191 participants with a follow-up of no less than 12 months. The MBL of ILP group showed no significant difference with that of DLP group (WMD 0.04, CI -0.13 to 0.21, P > .05). The subgroup analysis revealed similar results with Locator attachments or ball anchors (P > .05). Apart from one RCT (20%) with a high risk of bias, four RCTs (80%) showed a moderate risk of bias. Two prospective cohort studies were proved with acceptable quality. Seven included studies have reported ten implant failures in ILP groups and two implant failures in DLP groups in total.
Conclusions: For unsplinted mandibular implant-retained overdentures, the MBL around implants after ILP seems comparable to that of implants after DLP. Immediate loading may be a promising alternative to delayed loading for the management of unsplinted mandibular implant-retained overdentures.
PROSPERO registration number: CRD42020159124
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
This is a list of supplementary files associated with this preprint. Click to download.
Posted 11 Jan, 2021
On 25 Dec, 2020
On 25 Dec, 2020
On 25 Dec, 2020
On 28 Nov, 2020
Received 20 Nov, 2020
Received 05 Nov, 2020
On 02 Nov, 2020
On 01 Nov, 2020
On 22 Oct, 2020
Received 07 Oct, 2020
Received 03 Oct, 2020
On 29 Sep, 2020
Invitations sent on 29 Sep, 2020
On 29 Sep, 2020
On 29 Sep, 2020
On 28 Sep, 2020
On 28 Sep, 2020
On 20 Sep, 2020
Received 19 Sep, 2020
Received 16 Sep, 2020
On 11 Sep, 2020
On 09 Sep, 2020
Invitations sent on 08 Sep, 2020
On 18 Aug, 2020
On 17 Aug, 2020
On 17 Aug, 2020
On 16 Aug, 2020
Effects of immediate and delayed loading protocols on marginal bone loss around implants in unsplinted mandibular implant-retained overdentures: A systematic review and meta-analysis
Posted 11 Jan, 2021
On 25 Dec, 2020
On 25 Dec, 2020
On 25 Dec, 2020
On 28 Nov, 2020
Received 20 Nov, 2020
Received 05 Nov, 2020
On 02 Nov, 2020
On 01 Nov, 2020
On 22 Oct, 2020
Received 07 Oct, 2020
Received 03 Oct, 2020
On 29 Sep, 2020
Invitations sent on 29 Sep, 2020
On 29 Sep, 2020
On 29 Sep, 2020
On 28 Sep, 2020
On 28 Sep, 2020
On 20 Sep, 2020
Received 19 Sep, 2020
Received 16 Sep, 2020
On 11 Sep, 2020
On 09 Sep, 2020
Invitations sent on 08 Sep, 2020
On 18 Aug, 2020
On 17 Aug, 2020
On 17 Aug, 2020
On 16 Aug, 2020
Background: Immediate loading has recently been introduced into unsplinted mandibular implant-retained overdentures for the management of edentulous patients due to their increasing demand on immediate aesthetics and function. However, there is still a scarcity of meta-analytical evidence on the efficacy of immediate loading compared to delayed loading in unsplinted mandibular implant-retained overdentures. The purpose of this study was to compare the marginal bone loss (MBL) around implants between immediate and delayed loading of unsplinted mandibular implant-retained overdentures.
Methods: Randomized controlled trials (RCTs), controlled clinical trials (CCTs), and cohort studies quantitatively comparing the MBL around implants between immediate loading protocol (ILP) and delayed loading protocol (DLP) of unsplinted mandibular overdentures were included. A systematic search was carried out in PubMed, EMBASE, and CENTRAL databases on December 02, 2020. “Grey” literature was also searched. A meta-analysis was conducted to compare the pooled MBL of two different loading protocols of unsplinted mandibular overdentures through weighted mean differences (WMDs) with 95% confidence intervals (95% CIs). The subgroup analysis was performed between different attachment types (i.e. Locator attachment vs. ball anchor). The risk of bias within and across studies were assessed using the Cochrane Collaboration’s tool, the Newcastle-Ottawa scale, and Egger’s test.
Results: Of 328 records, five RCTs and two cohort studies were included and evaluated, which totally contained 191 participants with a follow-up of no less than 12 months. The MBL of ILP group showed no significant difference with that of DLP group (WMD 0.04, CI -0.13 to 0.21, P > .05). The subgroup analysis revealed similar results with Locator attachments or ball anchors (P > .05). Apart from one RCT (20%) with a high risk of bias, four RCTs (80%) showed a moderate risk of bias. Two prospective cohort studies were proved with acceptable quality. Seven included studies have reported ten implant failures in ILP groups and two implant failures in DLP groups in total.
Conclusions: For unsplinted mandibular implant-retained overdentures, the MBL around implants after ILP seems comparable to that of implants after DLP. Immediate loading may be a promising alternative to delayed loading for the management of unsplinted mandibular implant-retained overdentures.
PROSPERO registration number: CRD42020159124
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5