OBJECTIVE: This prospective randomized clinical trial was designed to compare the apical U-shape splitting technique (AUST) combined with guided bone regeneration (GBR) vs GBR alone for horizontal bone augmentation in maxillary labial undercut areas.
METHODS: The study included twelve patients with labial undercuts that made their alveolar ridges not able to compass dental implants. They received a total of 14 dental implants in the anterior maxilla where 7 (group I) were placed after AUST with GBR and the other 7 (group II) after the conventional GBR. The clinical and radiographic evaluations were done preoperatively, after surgery, and 6 months later. Facial flap fracture, peri-implant health, ridge width (RW) gain and loss, marginal bone loss (MBL), and implant esthetics were measured. Data were analyzed and compared and for any of the used tests, results were considered statistically significant if p-value ≤ 0.05.
RESULTS: For group I, no fracture of the bone flap happened and the gain in RW was significantly higher at 6 months postoperatively. Marginal bone loss was similar for both groups. The total pink esthetic score was significantly higher in group I vs group II (p = 0.024).
CONCLUSIONS: Within the limitations of this study, it was concluded that AUST combined with GBR was more effective in RW gain than GBR alone and it provided a merit approach for restoring function and esthetics if labial fenestration was unavoidable during implant placement.
CONCLUSIONS: Apical U-shape splitting technique for horizontal ridge augmentation is a valuable option for the benefit of patients in clinics who need dental implants and have anterior undercut areas that may lead to fenestration and usually requires onlay bone grafting which is less successful in maintaining the RW.

The aim of this study was to compare the clinical, tomographic, and histological performance of collagenated xenogeneic bone blocks (CXBB) in horizontal bone augmentations for implant placement. Five patients with an absence of the 4 upper incisors and an HAC 3 horizontal bone defect, with a remaining of 3 to 5 mm, underwent a bone-grafting procedure with CXBB (test group [TG], n = 5) and autogenous graft (control group [CG], n = 5), with one type of graft used on the right side and other type on the left side. Changes in bone thickness and density (tomographic evaluation), levels of complications (clinically), and distribution pattern between mineralized and nonmineralized tissue (histomorphometrically) were analyzed. Tomographic analysis showed a horizontal bone increase of 4.25 ± 0.78 mm in the TG and 3.08 ± 0.8 mm in the CG between baseline and 8 months postoperatively (P < .05). The horizontal loss between the day of installation of the blocks and 8 months postoperatively was 1.02 ± 0.39 mm for the TG and 1.10 ± 0.71 mm for the CG (P > .05). With regard to bone density, the TG blocks right after installation had 440.2 ± 89.15 HU, and after 8 months, the region reached 730.7 ± 130.98 HU, representing an increase of 29.05%. For the CG blocks, bone density increased from 1052.2 ± 398.35 HU to 1222.5 ± 453.28 HU, representing an increase of 17.03%. The increase in bone density was significantly higher in the TG (P < .05). Clinically, no cases of exposure of the bone blocks and no failure of incorporation were observed. Histomorphometrically, the percentage of mineralized tissue was lower in the TG than in the CG (48.10% ± 2.88% and 53.53% ± 1.05%, respectively), and the opposite was verified for the levels of nonmineralized tissue (52.79% ± 2.88% and 46.47% ± 1.05%, respectively; P < .05). The use of CXBB achieved higher levels of horizontal gain, with lower bone density and lower levels of mineralized tissue when compared with the use of autogenous blocks.

The objectives of this study were to observe hard tissue changes in guided bone regeneration (GBR) with intact periosteum and soft block deproteinised bovine bone mineral (DBBM), and evaluate whether the result of horizontal bone augmentation varied by initial peri-implant defect depth. Forty patients with a single missing tooth and contained peri-implant defect were categorised into three groups according to their presurgical defect depth (≤ 2, 2-4, and 4-6 mm). Cone-beam computed tomography (CBCT) images were collected and reconstructed preoperatively, postoperatively, and at six months\' follow up. The buccal bone width (BBW -0, -3, -5), alveolar bone width (ABW -0, -3, -5) and volume of augmented area were measured. At the six-month follow up the increase in BBW, ABW at all levels, and in bone volume, was statistically significant (all p < 0.001). No statistical significance in bone dimensions or bone resorption was found among groups (all p > 0.05). Histological analysis detected new bone formation in intimate contact with bone grafts underlying the periosteum. Within the limitations of this study, the insights gained may be of assistance to suggest that comparable and acceptable results of horizontal bone augmentation can be achieved in cases of peri-implant defect depth of ≤6 mm by means of GBR with intact periosteum.

UNASSIGNED: Placement of dental implant in narrow alveolar ridge is challenging to be treated. GBR procedure is currently most widely used to augment the deficient alveolar ridges and to treat the fenestration and dehiscence around dental implant. Thus, the objectives of the present study were to evaluate as well as compare the clinical performance of collagen membrane and titanium mesh for horizontal bone augmentation at dehisced implant sites.
UNASSIGNED: Total 12 single edentulous implant sites with buccal bone deficiency in 8 subjects were equally divided and treated simultaneously with either of the two membranes and DBBM(Bio-Oss) bone graft. Primary outcome measurements in terms of defect height and defect width were made using calibrated plastic periodontal probe. Re-entry surgery was performed to remeasure augmented site and to remove Ti-mesh at 6th months. Independent paired t-test for the inter-group comparison and student paired t-test for intra-group comparison were performed. The differences were considered to be significant at p ≤ 0.05.
UNASSIGNED: Mean defect fill with respect to height and width was 3.50 ± 0.54 mm (87%) and 2.33 ± 0.51 mm (82%) for collagen membrane and 3.83 ± 0.75 mm (92%) and 2.50 ± 0.54 mm (88%) for Ti-mesh group respectively.
UNASSIGNED: Within the limitation of the study, it was concluded that mean defect height and width after 6 months were statistically significant within the group without significant difference between them, Although defect resolution was better in Ti-mesh.

OBJECTIVE: The present systematic review and meta-analysis aimed to investigate the available evidence in the literature to answer the following focused question: In partially edentulous arches with reduced bone width, do implants placed after horizontal bone augmentation exhibit differences in survival and success rate compared to narrow-diameter implants placed in native bone?
METHODS: A population, intervention, comparison and outcome question was defined and an electronic search was conducted using the MEDLINE (via PubMed) and Cochrane Oral Health Group databases to identify all studies analysing the use of standard-diameter implants inserted in regenerated bone or narrow-diameter implants for the rehabilitation of partially or completely edentulous atrophic maxillae and mandibles. Inclusion criteria and quality assessments were established, and studies were selected on this basis.
RESULTS: Twenty-four studies met the inclusion criteria and were analysed cumulatively. A comparative meta-analysis was not possible due to the lack of studies directly comparing the two rehabilitation methods in question. A cumulative implant survival rate of 97.80% (1246/1274; pooled proportion 0.984, 95% confidence interval 0.977-0.991) was reported for the narrow implants placed in atrophic ridges, while similar results were obtained for the standard-diameter implants placed in regenerated bone, with a cumulative implant survival rate of 97.94% (1332/1360; pooled proportion 0.983, 95% confidence interval 0.976-0.990).
CONCLUSIONS: The present systematic review found high and comparable survival rates between narrow- and standard-diameter implants placed in regenerated bone; however, well-designed randomised controlled trials are required to support the hypothesis that both treatment strategies are successful in comparable circumstances.

OBJECTIVE: To introduce a novel and efficient procedure to solve a multidisciplinary issue connected to implant-related surgery in areas near periapical lesions of adjacent teeth using single-stage combined surgery while exploring a new way to prevent retrograde peri-implantitis.
METHODS: A 31-year-old woman diagnosed with a Kennedy III dentition defect in the maxillary right central incisor and posttreatment apical periodontitis in the maxillary right lateral incisor was treated using a multidisciplinary procedure. First, the preoperative data were collected from intraoral, extraoral facial and CBCT scans. Then, the aesthetic appearance of the anterior teeth was planned digitally and implant insertion was simulated. Next, virtual bone augmentation was carried out with reference to the simulated implant position, and according to the virtual augmentation, the templates for bone shell harvesting (also used for apical osteotomy and root tip resection during endodontic microsurgery) and bone shell grafting of the edentulous area were designed and fabricated. The templates for combined surgery (endodontic microsurgery and horizontal bone augmentation) consisted of one basal template and multiple interchangeable attachments via a plugin design to make guided endodontic microsurgery and digitally guided bone augmentation more efficient. Combined surgery was then carried out using the templates for guidance. During surgery, the apical inflammation affecting the maxillary right lateral incisor was first removed and its preserved apical bony window was prepared as an autogenous bone shell for bone augmentation of the maxillary right central incisor site. Guided bone regeneration of the edentulous area and guided tissue regeneration were then performed for the adjacent tooth. Six months after the combined surgery, digital guided implant surgery was carried out for the edentulous area. The final prosthesis was delivered in accordance with the preoperative aesthetic design and achieved using an implant-supported restoration for the maxillary right central incisor, full crown restoration for the maxillary right lateral incisor, and ceramic veneers for the maxillary left central and lateral incisors for space closure.
RESULTS: The horizontal bone augmentation in the edentulous area and endodontic microsurgery on the neighbouring tooth were performed successfully in a single-stage surgical procedure; thus, augmentation of the resorbed alveolar bone and removal of infection in the adjacent site were achieved simultaneously. At the 1-year follow-up after combined surgery, the healing of the natural maxillary right lateral incisor and the area having undergone bone augmentation showed promising results with no postoperative complications.
CONCLUSIONS: This novel digital workflow appears effective in addressing the problem of periapical lesions in retained teeth adjacent to the edentulous area that requires horizontal bone augmentation in one surgical procedure, providing an efficient way of resolving the problem using endodontics and implantology, and preventing retrograde peri-implantitis.

OBJECTIVE: The objective of this systematic review was to evaluate and compare the clinical efficacy of horizontal alveolar ridge augmentation techniques described by Khoury and Urban.
METHODS: A systematic electronic search in the MEDLINE databases, SCOPUS, WOS, and the Cochrane Central Register of Controlled Trials (CENTRAL) as well as a manual search, were conducted independently by two reviewers up to July 2021.
RESULTS: Six studies met the pre-established inclusion criteria and were included in the descriptive analysis. Due to the heterogeneity found across the included studies, meta-analysis could not be performed. Horizontal bone gain was between 3.93 ± 0.9 mm and 5.02 ± 0.8 mm with the Khoury technique and between 3.9 ± 0.9 mm and 5.68 ± 1.42 mm with the Urban technique. Similar complication rates were reported in both groups: infection (7%), in the Khoury technique, and membrane exposure (3.2-13.6%), in the Urban technique, being the most frequent events.
CONCLUSIONS: Both techniques were found to be effective, in terms of clinical bone gain, for horizontal alveolar ridge gain. Nevertheless, available literature is limited, and there is a lack of comparative studies to better evaluate the results.

Ridge augmentation for implant procedures has been shown to be highly successful. There are several techniques available to the dentist, but they require some degree of surgical expertise and experience. No particular technique has been shown to be superior. This article presents the indications, techniques, and complications of the various procedures for alveolar ridge augmentation. This information will educate the general dental practitioner of the techniques available and provide information on the surgical procedures that could be used to discuss with patients when they are being referred to a specialist.

The objective of this 3-year post-loading parallel randomised controlled trial is to compare two bone substitutes and resorbable membranes in a one-stage procedure for horizontal bone augmentation: anorganic bovine bone and porcine collagen membranes (BB group) versus synthetic resorbable bone graft substitute made of pure β-tricalcium phosphate and porcine pericardium collagen membranes (CJ group).
Patients in need of implant treatment having at least one site with horizontal osseous defect at a private clinic in Rimini, Italy, were included in this study. Patients were randomised to receive either BB or CJ in a one-stage procedure for horizontal bone augmentation in a submerged approach. Randomisation was computer-generated with allocation concealment by opaque sequentially numbered sealed envelopes. Patients and the outcome assessor were blinded to group assignment. The abutment connection was made after 6 months of healing. The application of the provisional prosthesis was performed after abutment connection and a definitive metal-ceramic prosthesis was placed 6 months post-loading. The patients were followed-up to 3 years post-loading. Primary outcome measures were: implant failure, complications and peri-implant margin bone level changes. Secondary outcome measures were: visual analogue scale (VAS) for functional and aesthetic satisfaction and pink aesthetic score (PES).
Twenty-five patients with 32 implants were randomly allocated to the BB group and 25 patients with 29 implants to the CJ group. All 50 randomised patients received the treatment as allocated and there were 7 drop-outs in the BB group and 11 drop-outs in the CJ group up to 3 years\' post-loading. There were no implant failures. There were six complications in five patients of the BB group and three complications in three patients of the CJ group (relative risk: 1.32, 95% CI from 0.37 to 4.64, P = 1.0000). Radiographic bone loss was 1.61 mm for the BB group and 1.02 mm for the CJ group (difference 0.54 mm, 95% CI from -0.53 to 1.60, P = 0.3100). The functional VAS was 9.0 for the BB group and 9.6 for the CJ group (difference 0.6, 95% CI from -0.4 to 1.5, P = 0.2393). The aesthetic VAS was 9.4 for the BB group and 9.6 for the CJ group (difference 0.2, 95% CI from -0.5 to 0.8, P = 0.6141). PES was 8.7 for the BB group and 8.5 for the CJ group (difference -0.1, 95% CI from -2.9 to 2.7, P = 0.9360).
No significant differences were observed in this randomised controlled trial comparing anorganic bovine bone with porcine collagen membranes versus synthetic resorbable bone made of pure β-tricalcium phosphate with pericardium collagen membranes for horizontal augmentation.

The aim of this study was to investigate a novel apical U-shape splitting technique for horizontal bone augmentation in undercut areas and to compare its efficacy with that of guided bone regeneration (GBR). This was a prospective non-randomized controlled clinical trial. A total of 36 patients, who presented with a labial undercut that was not able to house a normally inclined implant, underwent the new technique or GBR. Radiographic and clinical data were obtained preoperatively, immediately after surgery, and 12 months after surgery. Pairwise comparisons of changes in ridge width gain, marginal bone loss, and pink aesthetic score were performed; correlations with pristine ridge morphology were investigated. The results showed similar marginal bone loss in the two groups. The overall ridge width gains in the new technique group (2.56±1.92mm) and GBR group (0.73±1.21mm) differed significantly (P<0.05). The pink aesthetic score was higher for the new technique group (11.75±1.22) than for the GBR group (9.25±1.86) (P<0.01). The morphology of the concavity had different impacts on regeneration in the two groups. The apical U-shape splitting technique, as a safe and effective alternative to GBR, provided a significant increase in bone volume gain where labial fenestration was inevitable during implant placement.