Clinical assessment of maxillary screw-retained implant prosthesis fabricated from digital versus conventional full- arch implant impression. A randomized controlled clinical trial.

OBJECTIVES: To evaluate the peri-implant marginal bone loss (MBL) and prosthodontic complications of maxillary screw-retained implant prosthesis fabricated from digital versus conventional full- arch implant impression. MATERIAL AND METHODS: 28 participants with edentulous maxillary arches were randomly selected and enrolled in two equal groups; Group I conventional impression group (CIG) and Group II Digital impression group (DIG). All patients were rehabilitated with maxillary screwretained implant prosthesis retained by 6 implants. Peri-implant MBL and prosthodontic complications and were registered at 6, 12, and 24 months (m). Data was collected and statistically analyzed. RESULTS: Regarding the effect of time, there was a statistically significant increase in MBL at 6, 12 and 24 m follow-up periods (P<.001). As for the effect of groups, there was no statistically significant difference in MBL between CIG and DIG at 6, 12 and 24 m where P value was 0.083, 0.087 and 0.133 respectively. Prosthetic complications were recorded 19 times in the conventional group and 12 times in the digital group with no significant difference between both groups (P=.303). CONCLUSION: Digital full -arch implant impression is a reliable impression technique and may represent an alternative to conventional impression technique in the fabrication of maxillary screw-retained implant prosthesis.

Clinical influence of digital vs analog impressions in all-on-4 implant prostheses: a randomized controlled trial.

AIM: To compare the clinical outcomes of conventional and digital implant impressions in all-on-4 mandibular implant prostheses. MATERIALS AND METHODS: Fifty-six participants were randomly stratified into two control groups (Axial Conventional Impression Group [ACIG] and Tilted Conventional Impression Group [TCIG]), and two test groups (Axial Digital Impression Group [ADIG] and Tilted Digital Impression Group [TDIG]). Conventional pick-up and digital impressions were made for each group, respectively. Participants in ACIG and ADIG received four axial implants, and those in TCIG and TDIG received two anterior axial and two distal tilted implants. All participants received all-on-4 mandibular prostheses and maxillary complete dentures. Implant survival, prosthetic complications, and marginal bone loss were recorded at 6, 12, and 24 months. Data were statistically described in terms of mean ± standard deviation. RESULTS: After 24 months, the implant survival rate was 100%. A significant difference in bone loss was shown between ACIG and ADIG at 6, 12, and 24 months, with P = 0.647, 0.821, and 0.505, respectively. An insignificant difference in bone loss was shown between TCIG and TDIG at 6 ,12, and 24 months, with P = 0.671, 0.935, and 0.687, respectively. No significant difference was shown in prosthodontic complications between all groups throughout the follow-up period. CONCLUSIONS: The digital impressions showed clinically better implant survival, stable peri-implant marginal bone level, and reasonable prosthodontic complications. The present study represents a steppingstone and proof of concept that supports the routine clinical use of digital impressions, especially in a post-COVID-19 world.

Botulinum toxin and occlusal splints for the management of sleep bruxism in individuals with implant overdentures: A randomized controlled trial.

BACKGROUND: The available treatment options fail to provide definitive or curative management for bruxer patients rehabilitated with implant overdentures (OD). The data regarding Botulinum toxin (BTX) injection as a management strategy for bruxism remains unclear. This randomized, single-blinded, control-group, pretest-posttest prospective trial evaluated the occlusal guard and Botox injections (BTX) effectiveness in managing sleep bruxism (SB) in subjects whose one of the edentulous arches had been restored with the implant-supported OD. METHODS: Forty-two patients diagnosed with definite bruxism were selected, all of which had implant-retained ODs opposing natural dentition. The participants were allocated randomly to three equal groups. Participants in group I (control group) were instructed to remove the OD at night; group II was managed with conventional occlusal stents. Those in group III were given BTX injections. New ODs were constructed for all groups, and all ball attachments were replaced with a new nylon cap. A baseline assessment (one month of OD insertion) of patient satisfaction and sleep quality was conducted, and then again at 3, 6, 9, and 12 months of treatment. Subjective sleep quality was evaluated using Pittsburgh Sleep Quality Index (PSQI). Patients' satisfaction was evaluated using Temporomandibular disorders/numeric scales (TMD/NS). Prosthodontic (mechanical) complications were recorded during the follow-up period. RESULTS: Group III showed a statistically significant improvement in patient satisfaction and sleep quality compared to the other two groups at 3, 6, 9, and 12 months follow-up period ( P  = 0 0.001, 0.0001, 0.0013, and 0.0001 respectively). Regarding prosthodontic (mechanical) complications, the highest number of events was revealed in the control group. CONCLUSIONS: BTX and occlusal appliances effectively improve patient satisfaction and sleep quality of Bruxer patients rehabilitated with single arch implant overdentures.

Clinical evaluation of implant overdentures fabricated using 3D-printing technology versus conventional fabrication techniques: a randomized clinical trial.

AIM: To evaluate the oral health-related quality of life (OHRQoL) of patients rehabilitated with conventional or 3D-printed implant overdentures. MATERIALS AND METHODS: A randomized clinical trial (RCT) was designed. Twenty-eight completely edentulous participants were randomly allocated into two equal groups. All participants received two implants with ball attachments. Participants in the control group were rehabilitated with conventionally manufactured polymethyl methacrylate (PMMA) maxillary complete dentures (CDs) and mandibular implant overdentures, while those in the intervention group received digital light processing (DLP)-printed photopolymerizable PMMA maxillary CDs (NextDent) and mandibular implant overdentures. Follow-up appointments were scheduled at 3, 6, and 12 months where Oral Health Impact Profile 19 (OHIPEDENT19) data were used to assess the OHRQoL of the participants. Denture retention was measured using a digital force gauge device. RESULTS: The OHRQoL values were significantly higher (less improvement) in the conventional overdenture group at 6 months (P = 0.02) and 12 months (P = 0.04). A statistically significant difference was found between the mean retention values of the conventional and 3D-printed overdenture groups. For all the follow-up periods, the mean retention values were higher for the 3D-printed overdenture group (P = 0.001). CONCLUSION: 3D-printed overdentures may represent an alternative to conventionally fabricated ones. This study represents a stepping stone and proof of concept that support the potential future use of 3D-printed dentures.

Implant splinting in mandibular overdentures: a systematic review with meta-analysis of randomized clinical trials.

OBJECTIVES: To evaluate the influence of implant splinting on peri-implant marginal bone level and implant failures in completely edentulous patients who have been rehabilitated with mandibular implant overdentures. METHOD AND MATERIALS: A literature search of electronic databases (PubMed and Cochrane Central Register of Controlled Trials [CENTRAL]) was performed, with the last search conducted in July 2019. Randomized controlled trials with at least a 12-month follow-up period were selected. The review and meta-analysis were performed in accordance with PRISMA guidelines. Two comparisons were included in the meta-analysis: (1) Two-implant supported ball versus two-implant supported bar mandibular overdenture; (2): Two- versus four-implant supported bar mandibular overdenture. RESULTS: Six randomized controlled trials fulfilled the inclusion criteria and were included in a quality assessment and meta-analysis. Pooled data revealed a nonsignificant difference in marginal bone level (I2 = 0%; P = 1; mean difference = 0.00; 95% CI -0.37 to 0.37) and implant failures (P = .24; risk ratio = 6.07; 95% CI 0.30 to 121.33) when two-implant ball overdentures were compared to two-implant bar overdentures. Similarly, there was no significant difference in marginal bone level (I2 = 59%; P = .59; mean difference = -0.16; 95% CI -0.73 to 0.41) or implant failures (I2 = 0%; P = .36; risk ratio = 2.03; 95% CI 0.45 to 9.16) when two- versus four-implant bar overdentures were compared. CONCLUSION: Based on the findings of the meta-analysis, there is no influence of implant splinting on peri-implant marginal bone level and implant failures for completely edentulous patients rehabilitated with mandibular implant overdentures. However, this result should be interpreted with caution due to the limited number of analyzed studies, most of them considered at unclear risk of bias. Well-designed randomized controlled trials with follow-up periods of at least 5 years are highly recommended to establish evidence with regard to the influence of implant splinting on mandibular overdentures.

Single vs 2 Implants on Peri-implant Marginal Bone Level and Implant Failures in Mandibular Implant Overdentures: A Systematic Review With Meta-analysis.

BACKGROUND: As a consensus, the 2-implant supported overdentures (ODs) are considered as the first choice of treatment for the edentulous mandible. In the same context, there is increased evidence supporting the use of single-implant OD. The aim of any design is to preserve the remaining structures and allow the longevity of the treatment. OBJECTIVES: To evaluate the impact of single implant vs 2 implants on the peri-implant marginal bone loss (MBL) and number of implant failures in mandibular implant overdentures. METHODS: A literature search of electronic databases (PubMed and Cochrane) was performed up to March 2016 and complemented by hand search. Randomized clinical trials (RCTs) that evaluated MBL and number of implant failures relative to single-implant mandibular overdenture (MOD) were selected. The review and meta-analysis were performed using meta-analytic statistical package and in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. FINDINGS: Five RCTs met the inclusion criteria for systematic review and qualitative synthesis. The observation period ranged from 12 months to 5 years in the selected RCTs. The comparison included in the meta-analysis is single- vs 2-implant MODs. Pooled data revealed that single-implant MODs significantly decreased the MBL (mean difference: 0.27, 95% confidence interval: 0.20-0.34, P < .0001, I2 = 0%) and number of implant failures (risk ratio: 3.26, 95% confidence interval: 1.18-8.97), P = .02; I2 = 0%). CONCLUSIONS: Single-implant MOD was found to be better than 2-implant MOD in terms of MBL and number of implant failures. However, this result should be interpreted with caution due to limited number of analyzed studies with different loading protocols and short follow-up period.