Basel Elnayef, DDS, MS/Alberto Monje, DDS, MS/Jordi Gargallo-Albiol, DDS, PhD/Pablo Galindo-Moreno, DDS, PhD/Hom-Lay Wang, DDS, MS, PhD/Federico Hern?ndez-Alfaro, MD, DDS, FEBOMS, PhD: Purpose: To systematically appraise the effectiveness/reliability of vertical ridge augmentation (VRA) in the atrophic mandible. Articles that addressed any one of the following four areas were included in this study: amount of VRA, implant survival (ISR) and success rates (SSR) in the area of newly regenerated bone, complication rate during the bone augmentation procedure, and bone resorption. Materials and Methods: An electronic literature search was conducted by two independent reviewers in several databases, including MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register databases for articles reporting VRA in the atrophic mandible via distraction osteogenesis (DO), inlay block grafting (IBG), onlay block grafting (OBG), and guided bone regeneration (GBR). For meta-analysis, two primary (VRA and ISR [%]) and two secondary outcomes were studied (SSR [%] and vertical bone resorption [VBR] [%}). Additionally, for qualitative assessment, complications (ie, causes of failure) were further extracted and comprehensively described. Results: Overall, 73 full-text papers were evaluated. Of these, 52 articles fulfilled the inclusion criteria. The weight mean (WM) of VRA (? SD) was 4.49 ? 0.33 mm (95% CI: 3.85 to 5.14 mm). It was most notable that DO involved greater VRA than IBG, and thus, significantly higher than GBR and OBG. The technique significantly influenced the mean VRA obtained (P < .001). Nonetheless, no technique showed superiority in terms of ISR or SSR. VBR and complications were shown to be minimized for GBR. Conclusion: If ~ 4 mm of VRA is needed, any technique in optimum local and systemic conditions should be equally reliable in the atrophic mandible. However, when greater VRA is needed, DO and IBG have demonstrated accuracy. By means of complication and VBR rates, GBR was shown to have the lowest. For ISR and SSR, no statistical differences existed among all techniques. Controlled studies are needed to examine the long-term peri-implant bone fate and the frequency of biologic complications in each technique applied for the vertical augmentation of the atrophied mandible.

Basel Elnayef, DDS, MS, PhD/Cristina Porta, DDS, MS/Fernando Su?rez-L?pez del Amo, DDS, MS/Lorenzo Mordini, DDS, MS/Jordi Gargallo-Albiol, DDS, PhD/Federico Hern?ndez-Alfaro, MD, DDS, MS, PhD: Purpose: Owing to volumetric changes after tooth extraction, lateral ridge augmentation has become a common procedure prior or simultaneous to implant placement. Nonetheless, little is known with regard to the dimensional remodeling after healing of these lateral ridge augmentation procedures. Hence, the purpose of this systematic review was to assess the stability of bone grafting material between augmentation procedures and final healing, in terms of resorption rate. Materials and Methods: An electronic and hand literature search was conducted in several databases, such as the Cochrane Oral Health Group Trials Register, Embase, and Cochrane Central Register of Controlled Trials, up until February 2017. Only randomized controlled trials (RCTs) with a mean follow-up of at least 6 months after implant placement aiming to evaluate the stability of grafting material for lateral ridge augmentation were included and quantitatively analyzed. Results: A total of 35 articles were evaluated; however, only 17 RCTs met the inclusion criteria. A total of 15 studies reported information on bone resorption, leading to a total sample of 304 implants. The estimated overall mean horizontal bone gain at the time of regeneration was 3.71 ? 0.24 mm, with 4.18 ? 0.56 mm for the block graft technique and 3.61 ? 0.27 mm for guided bone regeneration (GBR). The estimated overall net bone gain at final re-evaluation (11.9 ? 7.8) was 2.86 ? 0.23 mm. The estimated mean (? SD) resorption after 6 months was 1.13 ? 0.25 mm, with 0.75 ? 0.59 mm for the block graft technique and 1.22 ? 0.28 mm for GBR. The implant survival rate was 97% to 100%. Conclusion: Regardless of the material used for regeneration, different degrees of graft resorption should be expected. Given the sample of investigations analyzed in this review, block grafts seemed to maintain the volume of the initial augmentation site more than GBR techniques. During the initial stages of healing, the GBR technique experienced more changes compared with block grafts. The resorption of the xenograft group was inferior compared with the combination of xenograft and autologous bone groups. Consequently, overcorrection of the horizontal defects should be performed to compensate for the resorption of the grafting materials.

Jordi Gargallo-Albiol, DDS, MS, PhD/Shayan Barootchi, DMD/Jordi Marqu?s-Guasch, DDS, MS/Hom-Lay Wang, DDS, MS, PhD: Purpose: To compare the accuracy of different modalities of implant placement?static fully guided, static half-guided, and freehand surgery?through meta-analysis. Materials and Methods: A thorough electronic and manual systematic search was conducted to identify applicable randomized clinical trials (RCTs) for evaluating the implant positioning accuracy between different static implant navigation surgeries. The coronal and apical horizontal deviation, vertical deviation, apical angle, and chair time were estimated as the weighted mean differences and standard deviation with confidence intervals. A P value of .05 was set for statistical significance. Results: Based on the 10 RCTs that met the inclusion criteria for the quantitative analyses, results from the meta-analyses demonstrated the following: (1) a coronal deviation significant difference favoring the fully guided approach compared with the half-guided (weighted mean difference of ?0.51 mm) and freehand approaches (weighted mean difference of ?1.18 mm); (2) a significant weighted mean difference between the fully guided and half-guided approaches in relation to the apical deviation (weighted mean difference of ?0.75 mm); (3) the vertical comparison did not yield significant weighted mean differences between the fully guided and half-guided techniques (?0.23 mm) and lacked statistically significant difference between the fully guided and freehand techniques (weighted mean difference of ?0.17 mm); (4) the apical angle deviation demonstrated a significant weighted mean difference in favor of the fully guided approach compared with the half-guided group (weighted mean difference of ?3.63 degrees); and (5) the comparison of chair time between the investigated groups did not exhibit a significant difference in any of the techniques. Conclusion: Static fully guided implant navigation surgery has the highest accuracy for transmitting the presurgical positioning planning to the patient, followed by static half-guided surgery, while the freehand implant placement provides the least accuracy.