Efficacy of laser biostimulation for mandibular narrow ridges treated with one-stage ridge splitting and two-implant overdentures: A one-year preliminary study.

STATEMENT OF PROBLEM: The management of patients with narrow-mandibular ridges who seek prosthetic rehabilitation is challenging. PURPOSE: The purpose of this one-year preliminary clinical study was to compare the effects of laser biostimulation and a placebo on peri-implant tissues for a 2-implant-retained mandibular polyetheretherketone (PEEK) overdenture on expanded narrow mandibular ridges. MATERIAL AND METHODS: Eighteen completely edentulous participants were enrolled for mandibular ridge splitting in the canine regions, followed by expansion, the placement of implants, and the application of a bone graft. In the test group, laser therapy was applied labially and lingually at the surgical sites, while a placebo laser was used in the control group. PEEK overdentures retained by LOCATOR attachments were provided after 6 months. Clinical evaluations were performed using probing depth, plaque, bleeding, and gingival indices at insertion and 3, 6, and 12 months after insertion. Vertical bone loss (VBL) was evaluated with periapical radiograph at insertion and 6 and 12 months later. The Mann-Whitney test was used to test the difference between the 2 different groups at each evaluation time (α=.05). The Friedman-test was used, followed by Wilcoxon signed rank test, to test the change over time in the same group, and the Bonferroni adjusted significance level was used for multiple comparisons. RESULTS: Some clinical and radiographic parameters significantly increased with time in both groups (P<.001). Significant differences between the 2 groups were revealed in bleeding scores at 3 months (P=.006) and 6 months (P=.018). Also, significant differences between the 2 groups were observed in gingival scores at 3 months (P=.002), 6 months (P=.015), and 12 months (P=.019) after overdenture insertion in favor of the laser group. Peri-implant VBL was significantly higher in the non-laser group at 6 months (P=.015), and 12 months (P=.001). CONCLUSIONS: Within the limitations of this clinical study, respecting the small sample size and the short follow-up period, laser bio-stimulation after 1-stage ridge splitting in narrow mandibular ridges enhanced the soft and hard peri implant tissues when used with LOCATOR attachments and PEEK overdentures.

Radiographic Assessment of Three-implant-retained Mandibular Overdentures: A Clinical Study of Alveolar Bone Height Changes (Randomized Clinical Trial).

AIM: To evaluate the residual alveolar ridge bone height changes regarding the impact of the block-out spacer used during the pick-up procedures of implant-assisted mandibular complete overdentures. MATERIALS AND METHODS: This study was a randomized clinical trial conducted on 18 patients. All patients received three mandibular dental implants with definitive locator attachments which were directly picked up with two different techniques. Patients were classified randomly without any bias into two equal groups (Group I block-out spacer) and (Group II without block-out spacer). Over a year, the digital radiographic technique with new technique of reference points was employed to evaluate the changes in the residual alveolar ridge bone heights. The data were statistically analyzed to test the significance difference between groups. RESULTS: Concerning the residual alveolar ridge resorption RRR, group I exhibited a significantly higher RRR than group II. CONCLUSION: In terms of residual alveolar ridge preservation, not using the block-out spacer was more beneficial than using it. CLINICAL SIGNIFICANCE: Alveolar bone heights can be affected by the use of block-out spacer during pick-up procedure within accepted physiologic values. The removal of the block-out spacer could be more beneficial with respect to the preservation of the residual alveolar ridge. How to cite this article: Mohammed REL, Askar OM, El-Waseef FAE, et al. Radiographic Assessment of Three-implant-retained Mandibular Overdentures: A Clinical Study of Alveolar Bone Height Changes (Randomized Clinical Trial). J Contemp Dent Pract 2023;24(11):847-852.

A comparison of mandibular denture base deformation with different impression techniques for implant overdentures.

PURPOSE: This study aimed to evaluate mandibular denture base deformation along with three impression techniques used for implant-retained overdenture. MATERIALS AND METHODS: Ten edentulous patients (five men and five women) received two implants in the canine region of the mandible and three duplicate mandibular overdentures which were constructed with mucostatic, selective pressure, and definitive pressure impression techniques. Ball abutments and respective gold matrices were used to connect the overdentures to the implants. Six linear strain gauges were bonded to the lingual polished surface of each duplicate overdenture at midline and implant areas to measure strain during maximal clenching and gum chewing. RESULTS: The strains recorded at midline were compressive while strains at implant areas were tensile. Clenching recorded significant higher strain when compared with gum chewing for all techniques. The mucostatic technique recorded the highest strain and the definite pressure technique recorded the lowest. There was no significant difference between the strain recorded with mucostatic technique and that registered with selective pressure technique. The highest strain was recorded at the level of ball abutment's top with the mucostatic technique during clenching. CONCLUSION AND RECOMMENDATION: Definite pressure impression technique for implant-retained mandibular overdenture is associated with minimal denture deformation during function when compared with mucostatic and selective pressure techniques. Reinforcement of the denture base over the implants may be recommended to increase resistance of fracture when mucostatic or selective pressure impression technique is used.