Success rate of dental implants inserted in horizontal and vertical guided bone regenerated areas: a systematic review

Robot-assisted dental implant surgery procedure: A literature review

Robot-assisted dental surgery has gained significant attention in the field of dental implant therapy as an alternative to conventional free-hand surgery. It addresses challenges faced by human operators, such as limited visibility, operator fatigue, and lack of experience, which can lead to errors. Dental implant robots offer improved precision, efficiency, and stability, enhancing implant accuracy and reducing surgical risks. Accurate placement of dental implants is crucial to avoid complications during and after surgery. Robotic guidance in dental implant surgery provides several benefits. Firstly, the robotic arm offers haptic feedback, allowing physical guidance when placing the implant in the desired position. Secondly, a patient tracker integrated into the robotic system monitors patient movement and provides real-time feedback on a screen. This feature ensures that the surgeon is aware of any changes and can adjust accordingly. Lastly, the robotic system operates under human-robot collaboration, with the surgeon maintaining control and oversight throughout the procedure. Therefore, the objective of the current study is to review the dental implant robots, as well as accuracy and efficiency (e.g. operation and preparation time) of robot-assisted dental implant surgery procedures.

No increased risk of osteonecrosis of the jaw in osteoporotic patients with dental implants: a nationwide cohort study

OBJECTIVES

The occurrence of implant-associated osteonecrosis of the jaw (ONJ) has been reported in osteoporotic patients, particularly in association with bisphosphonate therapy. This study aimed to investigate the risk of implant surgery and implant presence for ONJ occurrence in osteoporotic patients longitudinally.

METHODS

Based on Korean National Health Information Database, subjects over the age of 65 who were diagnosed with osteoporosis between July 2014 and December 2016 were included. The implant group included subjects who had undergone dental implant surgery between January 2017 and December 2017, while the control group included those who had no history of dental implants. The primary outcome was the occurrence of ONJ, and the date of final follow-up was December 2020.

RESULTS

A total of 332,728 subjects with osteoporosis were included in the analysis: 83,182 in the implant group and 249,546 in the control group. The risk of ONJ among those who had undergone implant surgery (risk of implant surgery-associated ONJ) was not higher than that among those without implant surgery. The risk of ONJ among those with implants (risk of implant presence-associated ONJ) was lower than that among those without implants. Even in subjects with a history of bisphosphonates, steroids, periodontitis, or tooth extraction, those who had undergone implant surgery or had implants did not have a higher ONJ risk than those who had not undergone surgery or did not have implants; rather, they showed a lower risk.

CONCLUSIONS

The results may suggest that dental implants are not associated with an increased risk of ONJ. A further study on whether dental implants are associated with lower ONJ risk is needed.

CLINICAL RELEVANCE

Dental implants did not increase the risk of ONJ development in osteoporotic patients, even with a history of bisphosphonates. This may suggest that the risk profiles for ONJ occurrence between selective insertion of dental implants and other dentoalveolar surgery associated with infectious conditions are different.

Morphology, Cytotoxicity, and Antimicrobial Activity of Electrospun Polycaprolactone Biomembranes with Gentamicin and Nano-Hydroxyapatite

The aim of this research is to develop new nanocomposite membranes (NMs) for guided bone regeneration from polycaprolactone (PCL), with different concentrations of gentamicin sulfate (GEN) and nano-hydroxyapatite (nHAP) through electrospinning. The obtained NMs were characterized for structure through SEM and AFM, which revealed the influence of GEN and nHAP on the fiber diameter. The addition of GEN lowered the fiber diameter, and the addition of nHAP increased the diameter of the fibers. The NMs demonstrated antibacterial properties against P. aeruginosa, S. aureus, B. cereus, and E. coli depending on the drug concentration, while being negligibly affected by the nHAP content. NM cytotoxicity assessment, performed once using the MTT assay, revealed no cytotoxicity. The developed NMs could be a promising alternative for guided bone regeneration.

Development, Characterization, and Antibacterial Analysis of the Selenium-Doped Bio-Glass-Collagen-Gelatin Composite Scaffold for Guided Bone Regeneration

Background Guided bone regeneration (GBR) is an often-used technique to aid the successful placement of dental implants in sites with deficient bone. The search for the ideal GBR membrane with bioactive components improving the regenerative outcomes is still on. In this study, a novel composite GBR membrane was developed using selenium-doped bio-glass, collagen, and gelatin. It was further characterized for surface, chemical, biocompatibility, and antibacterial properties. Methodology Selenium-doped bio-glass was prepared using the sol-gel method. The membrane was fabricated using an equal ratio of collagen and gelatin mixed with 1% selenium-doped bio-glass. The solution was poured to obtain a thin layer of the material which was lyophilized to obtain the final GBR membrane. The membrane was analyzed with scanning electron microscopy, energy dispersive X-ray (EDX) analysis, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), zebrafish cytotoxicity test, and antibacterial assay. Results The membrane revealed good surface roughness with lamellar and fibrillar arrangement with a minute granular surface ideal for cell attachment and proliferation. The EDX analysis revealed the presence of carbon, oxygen, and nitrogen as predominant components with trace amounts of calcium, phosphorus, silica, and selenium. Fourier transform infrared spectroscopy analysis also proved the presence of collagen, gelatin, and bio-glass. The membrane revealed excellent biocompatibility with zebrafish growth at a normal rate with 90% viability maintained at 48, 72, and 96 hours and 95% viability at 120 hours. It also exhibited excellent antibacterial activity against Staphylococcus aureus and Escherichia coli with minimal growth of bacterial colonies. Conclusion The developed novel selenium bio-glass collagen and gelatin composite scaffold has a good surface and antibacterial properties along with excellent biocompatibility. Further cell line and in vivo studies should be conducted to explore its role in bone regeneration.

Osteogenic differentiation and reconstruction of mandible defects using a novel resorbable membrane: An in vitro and in vivo experimental study

To evaluate the cellular response of both an intact fish skin membrane and a porcine-derived collagen membrane and investigate the bone healing response of these membranes using a translational, preclinical, guided-bone regeneration (GBR) canine model. Two different naturally sourced membranes were evaluated in this study: (i) an intact fish skin membrane (Kerecis Oral®, Kerecis) and (ii) a porcine derived collagen (Mucograft®, Geistlich) membrane, positive control. For the in vitro experiments, human osteoprogenitor (hOP) cells were used to assess the cellular viability and proliferation at 24, 48, 72, and 168 h. ALPL, COL1A1, BMP2, and RUNX2 expression levels were analyzed by real-time PCR at 7 and 14 days. The preclinical component was designed to mimic a GBR model in canines (n = 12). The first step was the extraction of premolars (P1-P4) and the 1st molars bilaterally, thereby creating four three-wall box type defects per mandible (two per side). Each defect site was filled with bone grafting material, which was then covered with one of the two membranes (Kerecis Oral® or Mucograft®). The groups were nested within the mandibles of each subject and membranes randomly allocated among the defects to minimize potential site bias. Samples were harvested at 30-, 60-, and 90-days and subjected to computerized microtomography (μCT) for three-dimensional reconstruction to quantify bone formation and graft degradation, in addition to histological processing to qualitatively analyze bone regeneration. Neither the intact fish skin membrane nor porcine-based collagen membrane presented cytotoxic effects. An increase in cell proliferation rate was observed for both membranes, with the Kerecis Oral® outperforming the Mucograft® at the 48- and 168-hour time points. Kerecis Oral® yielded higher ALPL expression relative to Mucograft® at both 7- and 14-day points. Additionally, higher COL1A1 expression was observed for the Kerecis Oral® membrane after 7 days but no differences were detected at 14 days. The membranes yielded similar BMP2 and RUNX2 expression at 7 and 14 days. Volumetric reconstructions and histologic micrographs indicated gradual bone ingrowth along with the presence of particulate bone grafts bridging the defect walls for both Kerecis Oral® and Mucograft® membranes, which allowed for the reestablishment of the mandible shape after 90 days. New bone formation significantly increased from 30 to 60 days, and from 60 to 90 days in vivo, without significant differences between membranes. The amount of bovine grafting material (%) within the defects significantly decreased from 30 to 90 days. Collagen membranes led to an upregulation of cellular proliferation and adhesion along with increased expression of genes associated with bone healing, particularly the intact fish skin membrane. Despite an increase in the bone formation rate in the defect over time, there was no significant difference between the membranes.

Sinus floor augmentation using crestal approach in conjunction with hydroxyapatite/cross-linked collagen sponge: A pilot study

BACKGROUND

Different biomaterials were suggested for sinus floor augmentation (SFA). Recently, new materials were launched showing true bone formation without remnants.

PURPOSE

The aim of this prospective study was to evaluate an hydroxyapatite-based, sugar cross-linked collagen sponge (OSSIX™ Bone) in transcrestal SFA (t-SFA).

MATERIALS AND METHODS

Twenty-four patients with edentulous posterior maxilla and residual bone height (RBH) >4 mm underwent t-SFA with OSSIX™ Bone as grafting material and simultaneous implant placement. The implant Stability Quotient (ISQ) was measured by resonance frequency analysis (RFA) directly after implant insertion and at 6 months. Differences in bone height (BH) and volume were determined in CBCT and x-rays at baseline versus 1 year of follow-up. Graft volume was evaluated by tridimensional reconstructions. Linear regression analysis was used to evaluate the effect of bucco-palatal sinus dimension, RBH, and length of the implant protruding (PIL) into the sinus, on the graft height (GH) changes up to 1 year, and on the graft volume at 1 year. Autocorrelation between time lag and augmented bone volume was evaluated through time series analysis correlograms. Health-related quality-of-life outcomes were captured.

RESULTS

Twenty-two patients completed the study. The mean RBH measured at baseline was 5.81 ± 2.2 mm. The mean graft volume was 1085.8 ± 733.4 mm3 . The mean GH, measured in the immediate post-operative period, at 6 and 12 months respectively, was 7.24 mm ±1.94; 6.57 mm ± 2.30; 5.46 mm ± 2.04. The mean ISQ measured after the implant placement was 62.19 ± 8.09, and 6 months later was 76.91 ± 4.50. There was a significant correlation between buccolingual dimension and graft volume at 1 year. Neither buccolingual volume nor RBH had a significant effect on GH change, while the PIL showed a significant positive correlation (P = 0.02 and P = 0.03 at 6 and 12 months, respectively). The correlograms indicated no significant correlation, meaning that there is no tendency for graft volume to increase or decrease over time, therefore suggesting graft stability, at least up to one year of follow-up. 86% of patients had no chewing interference.

CONCLUSION

Within the limitations of the study, OSSIX™ Bone could be considered a valid material for SFA due to its manageability and its positive results in promoting new bone formation with long-term stability. T-SFA is confirmed as a less invasive and less painful method.

Bone regeneration in implant dentistry: Which are the factors affecting the clinical outcome?

The key factors that are needed for bone regeneration to take place include cells (osteoprogenitor and immune-inflammatory cells), a scaffold (blood clot) that facilitates the deposition of the bone matrix, signaling molecules, blood supply, and mechanical stability. However, even when these principles are met, the overall amount of regenerated bone, its stability over time and the incidence of complications may significantly vary. This manuscript provides a critical review on the main local and systemic factors that may have an impact on bone regeneration, trying to focus, whenever possible, on bone regeneration simultaneous to implant placement to treat bone dehiscence/fenestration defects or for bone contouring. In the future, it is likely that bone tissue engineering will change our approach to bone regeneration in implant dentistry by replacing the current biomaterials with osteoinductive scaffolds combined with cells and mechanical/soluble factors and by employing immunomodulatory materials that can both modulate the immune response and control other bone regeneration processes such as osteogenesis, osteoclastogenesis, or inflammation. However, there are currently important knowledge gaps on the biology of osseous formation and on the factors that can influence it that require further investigation. It is recommended that future studies should combine traditional clinical and radiographic assessments with non-invasive imaging and with patient-reported outcome measures. We also envisage that the integration of multi-omics approaches will help uncover the mechanisms responsible for the variability in regenerative outcomes observed in clinical practice.

A prospective multicenter clinical study on the efficiency of detachable ball- and spring-retained implant prosthesis

PURPOSE

This prospective clinical study was conducted to evaluate the clinical usefulness of the freely detachable zirconia ball- and spring-retained implant prosthesis (BSRP) through a comparative analysis of screw- and cement-retained implant prosthesis (SCRP).

MATERIALS AND METHODS

A multi-center, randomized, prospective clinical study evaluating the clinical usefulness of the detachable zirconia ball- and spring-retained implant prostheses was conducted. Sixty-four implant prostheses in 64 patients were examined. Periodic observational studies were conducted at 0, 3, 6, and 12 months after delivery of the implant prosthesis. Factors such as implant success rate, marginal bone resorption, periodontal pocket depth, plaque and bleeding index, and prosthetic complications were evaluated, respectively.

RESULTS

During the 1-year observation period, all implants survived without functional problems and clinical mobility, showing a 100% implant success rate. Marginal bone resorption was significantly higher in the SCRP group than in the BSRP group only at the time of implant prosthesis delivery (P = .043). In all observation periods, periodontal pocket depth was slightly higher in the BSRP group than in the SCRP group, but there was no significant difference (P > .05). The modified plaque index (mPI) scores of both groups were moderate. Higher ratio of a score 2 in modified sulcus bleeding index (mBI) was observed in the BSRP group in the 6- and 12-months observation.

CONCLUSION

Within the limitations of this study, the newly developed zirconia ball- and spring-retained implant prosthesis could be considered as an applicable and predictable treatment method along with the existing screw- and cement-retained prosthesis.

Evaluation of the clinical and radiographic effectiveness of treating peri-implant bone defects with a new biphasic calcium phosphate bone graft: a prospective, multicenter randomized controlled trial

PURPOSE

Biphasic calcium phosphate (BCP), a widely used biomaterial for bone regeneration, contains synthetic hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP), the ratio of which can be adjusted to modulate the rate of degradation. The aim of this study was to evaluate the clinical and radiographic benefits of reconstructing peri-implant bone defects with a newly developed BCP consisting of 40% β-TCP and 60% HA compared to demineralized bovine bone mineral (DBBM).

METHODS

This prospective, multicenter, parallel, single-blind randomized controlled trial was conducted at the periodontology departments of 3 different dental hospitals. Changes in clinical (defect width and height) and radiographic (augmented horizontal bone thickness) parameters were measured between implant surgery with guided bone regeneration (GBR) and re-entry surgery. Postoperative discomfort (severity and duration of pain and swelling) and early soft-tissue wound healing (dehiscence and inflammation) were also assessed. Data were compared between the BCP (test) and DBBM (control) groups using the independent t-test and the χ² test.

RESULTS

Of the 53 cases included, 27 were in the test group and 26 were in the control group. After a healing period of 18 weeks, the full and mean resolution of buccal dehiscence defects were 59.3% (n=16) and 71.3% in the test group and 42.3% (n=11) and 57.9% in the control group, respectively. There were no significant differences between the groups in terms of the change in mean horizontal bone augmentation (test group: -0.50±0.66 mm vs. control groups: -0.66±0.83 mm, P=0.133), postoperative discomfort, or early wound healing. No adverse or fatal complications occurred in either group.

CONCLUSION

The GBR procedure with the newly developed BCP showed favorable clinical, radiographic, postoperative discomfort-related, and early wound healing outcomes for peri-implant dehiscence defects that were similar to those for DBBM.

TRIAL REGISTRATION

Clinical Research Information Service Identifier: KCT0006428.

A Novel Approach for Implant Rehabilitation Combined with Immediate Bone and Soft-Tissue Augmentation in a Compromised Socket—A B2S Approach: Case Report with a 2-Year Follow-Up

In this case report, we aimed to describe a novel approach for aesthetic rehabilitation of the anterior maxilla that combined immediate implant installation with the “Bone2Soft Tissue Reconstruction” (B2S technique), which involves the use of a triple graft harvested from the maxillary tuberosity. The regeneration potential of a tuberosity graft appeared to surpass that of corticocancellous bone grafts harvested from other intraoral donor sites and allowed for quicker regeneration of both bone and soft tissue. The B2S technique extended the indications for immediate implant placement and ridge augmentation to cases involving severe bone resorption and other complex clinical scenarios. Owing to the good visualization facilitated by open-flap access, the surgical procedures can be completed in a single intervention, which will be beneficial for both doctors and patients.

Effects of a locally administered risedronate/autogenous bone graft combination on bone healing in a critical-size rabbit defect model

BACKGROUND

Risedronate is a bisphosphonate with poor oral absorption. An extremely hydrophilic molecule that has a high affinity for bone, risedronate also inhibits the farnesyl diphosphate synthase enzyme, inhibiting osteoclastic activity and reducing bone turnover and resorption. Autogenous bone grafts contain osteogenic cells and osteoinductive factors that are essential for bone regeneration and are therefore considered the gold standard. Thus, this study aimed to investigate the impact of local risedronate administered with autogenous bone grafts on the healing of defects in rabbit skulls using histological, histomorphometric, immunohistochemical, and three-dimensional radiological methods.

METHODS

Two 10-mm-diameter critical-size defects were created in 16 rabbits and filled with autogenous bone graft and autogenous bone graft + 5 mg risedronate in the control (C) and risedronate (RIS) groups, respectively. Residual graft, new bone, soft tissue areas, and bone volume were evaluated in the 4- and 8-week study groups.

RESULTS

There were no statistically significant differences in bone graft, new bone, or soft tissue area between the groups at 4 weeks (p > 0.05). At 8 weeks, the new bone area was significantly higher in the RIS group than in the C group (p < 0.05). The h scores obtained from sialoprotein and osteopontin did not differ significantly between the groups (p > 0.05). The radiologically measured total bone volume was significantly higher in the RIS group than in the C group at both time points (p < 0.05).

CONCLUSIONS

In this study, risedronate enhanced the osteoconductive properties of autogenous bone grafts and rapidly created better-quality bone. This could improve future patient outcomes.

Marginal bone loss of tissue- or bone-level implants after simultaneous guided bone regeneration in the posterior mandibular region: A retrospective cohort study

PURPOSE

To analyze the marginal bone loss (ΔMBL) of tissue- or bone-level implants after placed with simultaneous guided bone regeneration (GBR).

MATERIALS AND METHODS

A total of 151 patients who received 104 tissue-level or 128 bone-level implants placement with simultaneous GBR in the mandibular posterior region between January 2011 and December 2016 were included in this study. The marginal bone level (MBL) was recorded using the radiographic data obtained at implant placement, second-stage surgery, and the follow-up visit. Generalized estimating equation (GEE) was used to compare the ΔMBL of tissue- and bone-level implants, and the influencing factors of ΔMBL were further analyzed.

RESULTS

At the last follow-up visit, the MBL of tissue-level implants was 0.73 ± 0.86 mm, above the rough-smooth interface, while that of bone-level implants was 0.82 ± 1.05 mm, above the implant platform. The ΔMBL of tissue-level implants was 1.03 mm, which was slightly higher than 0.81 mm of bone-level implants, but there was no significant difference (p > 0.05). No contributing factor associated with ΔMBL was identified by multivariate regression analysis in this study.

CONCLUSION

Within the limits of this retrospective analysis, the ΔMBL of tissue-level implants is similar to that of bone-level implants after placed with simultaneous GBR, and both types of implants can achieve desirable marginal bone stability.

Titanium Mesh Exposure After Bone Grafting: Treatment Approaches-A Systematic Review

Study Design

A systematic review according to PRISMA statement has been designed to answer the preliminary question: "In titanium mesh exposures, is there a treatment alternative which leads to an increased graft maintenance?" and fill the PICO assessment out.

Objective

To review studies published in the past 20 years (1999-2019) in which mesh exposure has occurred, detecting the suitable approaches to treat exposure allowing the graft maintenance.

Methods

Initial search on PUBMED, SCOPUS, and COCHRANE databases resulted in 777 articles, and hand-searching identified 6 articles. After removing duplicates and unrelated articles, eligibility criteria were applied, and 31 studies were selected (randomized clinical trials, retrospective/prospective clinical trials, and case series).

Results

A total of 677 surgical sites and 225 cases of mesh exposure were identified. Eleven treatments have been identified. Chlorhexidine was the primary approach in 46% of cases, followed by oral hygiene instructions and follow-up with 22.5% of occurrences. In 21% of clinical situations, titanium mesh removal was the treatment of choice, associated with other measures (i.e., antibiotic prescription). There seems to be a consensus in cases of infection. When this complication was associated with tissue dehiscence, the primary treatment was mesh removal. The same does not occur when the site needs to be cleaned for long-term periods.

Conclusion

In 2 decades of use of titanium meshes, the available treatments do not seem to have evolved, and there is not enough data to establish a guideline.

The Use of Biocompatible Membranes in Oral Surgery: The Past, Present & Future Directions. A Narrative Review

The use of biocompatible membranes in periodontal and oral surgery is an important part of regeneration. Over the years, several different membranes have been developed, ranging from non-resorbable membranes that have to be removed in a separate procedure, to collagen membranes that completely resorb on their own, thus avoiding the need for a second surgery. Autogenous membranes are becoming increasingly popular in more recent years. These membranes can be used with a great variety of techniques in the four main hard tissue regenerative procedures: guided tissue regeneration, alveolar ridge preservation, guided bone regeneration and sinus floor augmentation. A review of the literature was conducted in order to identify the most commonly used membranes in clinical practice, as well as the most promising ones for regeneration procedures in the future. The information provided in this review may serve as a guide to clinicians, in order to select the most applicable membrane for the clinical case treated as the correct choice of materials may be critical in the procedure's success.

Tailoring Cu2+-loaded electrospun membranes with antibacterial ability for guided bone regeneration

Copper (Cu)-loaded electrospun membranes were tailored for guided bone regeneration (GBR), targeting the stimulation of innate cells active in bone growth and the prevention of bacterial infections. Functional GBR membranes were produced via an electrospinning set-up using a silk-based solution associated with polyethylene oxide (Silk/PEO - control). Experimental groups were loaded with copper oxide using varying weight percentages (0.05 % to 1 % of CuO). The morphological, structural, chemical, and mechanical properties of membranes were evaluated. Direct and indirect in vitro cytocompatibility experiments were performed with primary human bone mesenchymal stem cells and primary human umbilical vein endothelial cells. The antibacterial potential of membranes was tested with Staphylococcus aureus and Fusobacterium nucleatum biofilm. CuO was successfully incorporated into membranes as clusters without compromising their mechanical properties for clinical applicability. Increased Cu concentrations generated membranes with thinner nanofibers, greater pore areas, and stronger antimicrobial effect (p < 0.01). Cu²⁺ ion was released from the nanofiber membranes during 1 week, showing higher release in acidic conditions. CuO 0.1 % and CuO 0.05 % membranes were able to support and stimulate cell adhesion and proliferation (p < 0.05), and favor angiogenic responses of vascular cells. In addition, detailed quantitative and qualitative analysis determined that amount of the attached biofilm was reduced on the tailored functional Cu²⁺-loaded GBR membrane. Importantly, these qualities represent a valuable strategy to improve the bone regeneration process and diminish the risk of bacterial infections.

Effectiveness of Different Antimicrobial Agents on Malodor Prevention in Two-Stage Dental Implants: A Double-Blinded Randomized Clinical Trial

OBJECTIVE

 Opening of a healing abutment in two-stage implant systems is usually followed by a bad smell. Previous studies have found that presence of bacteria in microleakages of the implant-abutment interface results in further malodor. However, studies focusing on preventive treatments for this issue are scarce. Therefore, the aim of this study is to evaluate the effectiveness of two antimicrobial agents on prevention of malodor followed by opening the healing abutments.

MATERIALS AND METHODS

 Current double-blinded randomized clinical trial was performed on 51 eligible patients who were referred for their exposure surgery. They were divided equally into three parallel groups. In two groups, either chlorhexidine or tetracycline was added to the internal surface of the fixtures before screwing the healing abutments. One group did not receive any intervention. Three to 4 weeks later malodor was scored by sniffing the healing abutments immediately after uncovering them (odorless = 0/odor = 1). The three groups were then compared regarding malodor scores.

RESULTS

 Our findings showed that malodor was more frequent in the control group (58.82%) in comparison with groups of intervention (17.65 and 23.53%). There was a statistically significant difference between malodor in patients in whom antimicrobial agents (chlorhexidine and tetracycline) were used in their implants and the control group (p-value = 0.023). However, malodor in the chlorhexidine group and tetracycline group did not show any significant difference (p-value = 1).

CONCLUSION

 Based upon the data from this study, it appears that local antimicrobial agents including chlorhexidine and tetracycline result in less malodor production within the implant-abutment interface.

CLINICAL SIGNIFICANCE

 A specific type of malodor is commonly seen after opening the healing abutment of a two-stage dental implant. Not only this issue is noticed by the dentist, but also annoyed the patient. Using local antimicrobial agents in the fixtures is likely to be a simple, easily applicable solution that satisfies both patients and dentists, and eliminates the possibility of further inflammation.

Analysis of implant loss risk factors after simultaneous guided bone regeneration: A retrospective study of 5404 dental implants

PURPOSE

The purpose was to analyze the risk factors for implant loss after simultaneous guided bone regeneration (GBR).

MATERIALS AND METHODS

Patients who underwent implant placement with simultaneous GBR between January 2011 and December 2018 were screened for this study. The cumulative survival rate (CSR) was calculated using the life table method. Log-rank test and Kaplan-Meier survival estimates were used to identify potential risk factors for implant loss. The association between the investigated variables and implant loss was determined using hazard ratios (HRs) obtained from a multivariate Cox regression analysis.

RESULTS

A total of 3973 patients with 5404 implants were included in this study. The CSRs of the implants at 1, 5, and 10 years were 99.6%, 98.9%, and 98.7%, respectively. Male patient (HR = 2.94, 95% CI: 1.41-6.14), periodontitis (HR = 4.26, 95% CI: 2.05-9.86), tissue-level implants (HR = 3.02, 95% CI: 1.30-6.98), narrow implants (HR = 2.71, 95% CI: 1.12-6.57), and implant length ≤10 mm (HR = 2.91, 95% CI: 1.41-6.02) significantly increased the risk of implant loss (p < 0.05). The risk of implant loss was significantly higher in the maxillary posterior region (HR = 2.26, 95% CI: 1.04-4.90) than in the maxillary anterior region (p < 0.05). Compared to Straumann, Nobel (HR = 4.07, 95% CI: 1.75-9.44) and other implant systems (HR = 14.23, 95% CI: 4.32-46.85) showed a significantly higher risk of implant loss (p < 0.05).

CONCLUSION

Male patient, periodontitis, maxillary posterior region, Nobel implant system, other implant systems, tissue-level implants, narrow implants, and implant length ≤10 mm were considered risk factors for implant loss after simultaneous GBR.

Healing complications and their detrimental effects on bone gain in vertical-guided bone regeneration: A systematic review and meta-analysis

PURPOSE

Guided bone regeneration (GBR) utilizes a barrier membrane to allow osteogenic cells to populate a space by excluding epithelial and connective tissue cells. The purpose of this systematic review was to investigate the ratio of means (RoM) of vertical bone gained (Outcome) in vertical GBR procedures with healing complications (Intervention) and in vertical GBR procedures without healing complications (Comparison) in patients with vertically resorbed edentulous ridges that require dental implant placement (Population). A further aim was to investigate the incidence of complications after vertical GBR, and the influence of the timing of implant placement and regenerative devices on complications.

MATERIALS AND METHODS

MEDLINE (through PubMed), EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched in duplicate up to, and including, November 2020 for randomized and controlled clinical trials and prospective and retrospective case series. Outcomes included patient-level and site-level RoM of vertical bone gain between healing complications and uneventful healing, and incidences of complications that occurred after vertical GBR. Random-effects and fixed-effects meta-analyses were performed where appropriate. This study was registered on PROSPERO (CRD42021226432).

RESULTS

A total of 31 publications were selected for the qualitative and quantitative analyses. The RoM of vertical bone gained was 0.65 [95% CI = 0.47, 0.91] and 0.62 [95% CI = 0.45, 0.85] when membrane exposure without suppuration and abscess formation without membrane exposure occurred respectively, in comparison to uneventful healing. The overall incidence proportion of healing complications occurring at the augmented site at a site- and patient-level was 11.0% [95% CI = 7.0, 15.6] and 10.8% [95% CI = 6.6, 15.7]. At a patient-level, there were no significant differences between a simultaneous or staged approach, or with the regenerative device used. The site-level incidence proportion of membrane exposure without suppuration, membrane exposure with suppuration, and with abscess formation without membrane exposure was 8.7% [95% CI = 4.2, 14.2], 0.7% [95% CI = 0.0, 2.9], and 0.5% [95% CI = 0.0, 1.7], respectively. The site-level weighted mean incidence proportion of neurologic complications occurring at the donor site was 0.8% [95% CI = 0.0, 5.3].

CONCLUSIONS

There is a significant reduction in bone gain when healing complications occur. However, healing complications are relatively uncommon surgical complications after vertical GBR.

Effects of Systemic Propranolol Application on the New Bone Formation in Periimplant Guided Bone Regeneration

Objectives

The aim of this experimental animal study was to evaluate the effects of systemic propranolol on new bone formation in peri-implant bone defects.

Material and Methods

Implant slots were created 4mm long and 2.5 mm wide. After the titanium implants were placed in the sockets, 2 mm defects were created in the neck of the implants. Bone grafts were placed in these defects. Then the rats were randomly divided into three equal groups: control (n = 8), propranolol dose-1 (PRP-1) (n = 8), and propranolol dose-2 (PRP-2) (n = 8) groups. In the control group, the rats received no further treatment during the eight-week experimental period after the surgery. The rats in the PRP-1 and PRP-2 groups were given 5 mg/kg and 10 mg/kg propranolol, respectively, every three days for the eight-week experimental period after the surgery. At the end of the experimental period, the rats were euthanized. Blood serum was collected for biochemical analysis, and the implants and surrounding bone tissues were used for the histological analysis.

Results

There were no significant differences in the histological analysis results and the biochemical parameters (alkaline phosphatase, calcium, creatinine and phosphorus) of the groups (P > 0.05). Also, in the test groups, there was numerically but not statistically more new bone formation detected compared with the controls.

Conclusions

Within the limitations of this study, propranolol did not affect the new bone formation in peri-implant defects.

Success of dental implants in patients with large bone defect and analysis of risk factors for implant failure: a non-randomized retrospective cohort study

OBJECTIVES

This study aimed to retrospectively investigate the success and survival rates of dental implants used for dentomaxillary prostheses at our hospital and the risk factors associated with large bone defects.

MATERIALS AND METHODS

A total of 138 external joint system implants used for dentomaxillary prostheses in 40 patients with large bone defects were included in this study. The alveolar bone at the site of implant insertion was evaluated using panoramic radiography and computed tomography. Various risk factors (demographic characteristics, dental status, and operative factors such as the employment of alveolar bone augmentation, the site, the length, and diameter of implants) for implant failure and complete implant loss were investigated using univariate and multivariate analyses. The associations between the variables and the success and survival rates of dental implants were analyzed using the multivariate Cox proportional hazard models.

RESULTS

The 10-year overall success and survival rates were 81.3% and 88.4% in this study. Multivariable analysis showed that the male sex (HR 6.22), shorter implants (≤ 8.5 mm) (HR 5.21), and bone augmentation (HR 2.58) were independent predictors of success rate. Bone augmentation (HR 5.14) and narrow implants (≤ 3.3 mm) (HR 3.86) were independent predictors of the survival rate.

CONCLUSION

Male sex, shorter or narrow implants, and bone augmentation were independent risk factors for dental implants used in dentomaxillary prostheses in patients with large bone defects.

CLINICAL RELEVANCE

Clinicians should consider these risk factors and pay close attention to the management of these patients.

Regenerative Medicine Technologies to Treat Dental, Oral, and Craniofacial Defects

Additive manufacturing (AM) is the automated production of three-dimensional (3D) structures through successive layer-by-layer deposition of materials directed by computer-aided-design (CAD) software. While current clinical procedures that aim to reconstruct hard and soft tissue defects resulting from periodontal disease, congenital or acquired pathology, and maxillofacial trauma often utilize mass-produced biomaterials created for a variety of surgical indications, AM represents a paradigm shift in manufacturing at the individual patient level. Computer-aided systems employ algorithms to design customized, image-based scaffolds with high external shape complexity and spatial patterning of internal architecture guided by topology optimization. 3D bioprinting and surface modification techniques further enhance scaffold functionalization and osteogenic potential through the incorporation of viable cells, bioactive molecules, biomimetic materials and vectors for transgene expression within the layered architecture. These computational design features enable fabrication of tissue engineering constructs with highly tailored mechanical, structural, and biochemical properties for bone. This review examines key properties of scaffold design, bioresorbable bone scaffolds produced by AM processes, and clinical applications of these regenerative technologies. AM is transforming the field of personalized dental medicine and has great potential to improve regenerative outcomes in patient care.

Augmentation stability and early wound healing outcomes of guided bone regeneration in peri-implant dehiscence defects with L- and I-shaped soft block bone substitutes: A clinical and radiographic study

OBJECTIVES

To retrospectively evaluate whether guided bone regeneration (GBR) with L- and I-shaped demineralized bovine bone mineral with 10% collagen (DBBM-C) differs from GBR with DBBM in terms of augmentation stability and early wound healing outcomes in peri-implant dehiscence defects.

METHODS

A total of 91 peri-implant defects were grafted with 24 L- (GBR-L), 22 I (GBR-I)-shaped DBBM-C, and 45 DBBM (GBR-P). Cone-beam computed tomography images were obtained after surgery and at 5 months follow-up. The horizontal thickness (HT0, HT2, HT4), vertical thickness (VT), and VT at 45° angle (45-VT) of the augmented hard tissue were measured. Early postoperative discomfort and wound healing outcomes were assessed 2 weeks after surgery, and periotest values were also measured at 5 months in all groups.

RESULTS

At 5 months follow-up, the change at HT0 and VT of the GBR-L (HT0: -0.63 ± 0.55 mm, VT: -0.77 ± 0.60 mm) and GBR-I (HT0: -0.68 ± 0.53 mm, VT: -0.91 ± 0.73 mm) groups was significantly more stable than that of the GBR-P (HT0: -1.30 ± 0.77 mm, VT: -1.57 ± 0.67 mm) group (p < .05). The GBR-L group (-0.74 ± 0.54 mm) showed better augmentation stability than the other two groups at the change at 45-VT. Early postoperative discomfort, wound healing outcomes, and periotest values did not differ significantly between the three groups.

CONCLUSION

Within the limitations of this study, L- and I-shaped DBBM-Cs used for GBR were more beneficial in terms of horizontal augmentation stability than DBBM after a 5-month healing period.

Customized-3D zirconia barriers for guided bone regeneration (GBR): clinical and histological findings from a proof-of-concept case series

OBJECTIVES

The aim of this case series was to evaluate, clinically and histologically, customized-3D zirconia barriers manufactured for guided bone regeneration (GBR) procedures.

METHODS

Seven healthy consecutive patients with severe bone atrophy (two of them with a bilateral atrophy) were selected for a GBR procedure with a zirconia barrier. In a 3D software (DentalCad, Exocad GmbH, Germany), a virtual bone graft was designed and a shell was designed covering the graft; a standard tessellation language (.STL) file was obtained and milled (M1, Zirkonzahn, Italy) using a 1200 MPa zirconia (Prettau, Zirkonzahn, Italy). Nine GBR surgeries (8 upper-posterior jaw, 1 lower-posterior jaw) were performed using autogenous bone chips mixed with xenograft (SmartBone, IBI-SA, Switzerland / BioOss, Geistlich, Switzerland) covered with a zirconia barrier, fixed by means of screws. After healing, implant sites were prepared with a trephine bur, collecting a bone biopsy, and dental implants were inserted (Neodent, Straumann Group, Switzerland). Specimens were histologically analyzed.

RESULTS

Eight successful surgeries were recorded; one zirconia barrier got exposed after one month of healing but no signs of infection were present till the barrier was removed. In all cases it was possible to insert implants with no additional bone augmentation procedures. Histological evaluations showed the presence of intense deposition of new bone.

CONCLUSIONS

Within the limitations of the present case series, the tested customized-3D zirconia barriers confirmed good clinical and histological performances, and, even in case of premature exposure, did not show signs of infection. Preliminary results suggest they are effective for GBR procedures. Further research is necessary with a larger sample size.

CLINICAL SIGNIFICANCE

The presented barriers could be a viable alternative to titanium-reinforced polytetrafluoroethylene membranes and customized meshes.

Biomechanical Evaluation of Implant Osseointegration After Guided Bone Regeneration With Different Bone Grafts

ABSTRACT

The aim of this study was to compare the biomechanical osseointegration of titanium implants after guided bone regeneration (GBR) with a hydroxyapatite graft, deproteinized bovine bone graft, human-derived allograft, and calcium sulfate bone graft. Thirty-two female Sprague Dawley rats were divided into four groups, each containing eight (n = 8) rats: hydroxyapatide (HA), deproteinized bovine bone graft (DPBB), allograft (ALG), and calcium sulfate. Bone defects were created in the tibia of the rats, which were grafted with HA, DPBB, ALG, or CP bone grafts for the purpose of GBR. Ninety days after surgery, machine-surfaced titanium implants were inserted into the area where GBR had been undertaken. After 90 days of the surgical insertion of the implants, the rats were sacrificed, the implants with surrounding bone tissue were removed, and biomechanical osseointegration (N/cm) analysis was performed. No statistically significant differences were found among the groups in osseointegration (N/cm) three months after the GBR procedures (P > 0.05). According to the biomechanical results, none of the grafts used in this study was distinctly superior to any of the others.

Guided bone regeneration simultaneous with implant placement using bovine-derived xenograft with and without liquid platelet-rich fibrin: a randomized controlled clinical trial

OBJECTIVE

To assess augmentation success after guided bone regeneration (GBR) carried out simultaneously with implant placement using bovine-derived xenograft alone and in combination with liquid platelet-rich fibrin (liquid-PRF).

METHODS

This randomized controlled clinical trial was conducted on patients with horizontal bone deficiency in the posterior regions of the mandible. After implant placement, GBR procedures were randomly performed using liquid-PRF-enriched bovine-derived xenograft (for the test group) and with bovine-derived xenograft alone (for the control group). To assess the change in augmentation thickness, the primary outcome of the study, cone beam computed tomography was carried out at the implant sites on completion and 6 months after surgery. The secondary outcomes were marginal bone level and implant survival rate at prosthetic delivery and at 6 months, 1 year, and 2 years follow-up after loading. The significance level was set at p<0.05 for all analysis.

RESULTS

Twenty patients with 50 implants were analyzed for the test group and 20 patients with 48 implants for the control group. At 6 months postoperatively, the mean values of augmentation thickness were 1.63 ± 0.21 mm, 2.59 ± 0.34 mm, and 3.11 ± 0.36 mm for the test group and 1.34 ± 0.14 mm, 2.49 ± 0.24 mm, and 2.97 ± 0.24 mm for the control group at 2 mm, 4 mm, and 6 mm below to the implant shoulder (p < 0.001, p = 0.007, and p = 0.036, respectively). The mean marginal bone loss was found to be less than 1 mm for both study groups during the 2 years of follow-up after prosthetic loading. Implant survival rate was 100% for both study groups.

CONCLUSION

Bovine-derived xenograft alone and in combination with liquid-PRF are both successful in achieving bone augmentation around the implants and produce a small change in marginal bone level and a high implant survival rate after loading.

CLINICAL RELEVANCE

There is a lack of evidence in the literature regarding the augmentation success of liquid-PRF used in combination with bone graft substitutes. This study indicates that liquid-PRF could be used as a supportive material with bovine-derived xenograft in GBR procedures carried out simultaneously with implant placement.

A Retrospective Analysis of Treatment Outcomes Following Guided Bone Regeneration at Sites Exhibiting Severe Alveolar Ridge Atrophy

ABSTRACT

Severely atrophic alveolar ridges represent a great challenge for implant-prosthetic rehabilitations. The aim of this study was to clinically and histologically evaluate horizontal and vertical bone gain, as well as implant survival/success rate after guided bone regeneration (GBR) for the reconstruction of large bone defects. Fourteen subjects (7 males and 7 females; mean age: 48.9 ± 14.1) were enrolled in the study. They were selected according to specific inclusion criteria and all patients required GBR procedures for placing implants in severe atrophic jaws (bone height ≤6 mm). Guided bone regeneration was performed using dense polytetrafluoroethylene nonresorbable titanium-reinforced membranes associated with particulate heterologous bone grafts. Implant placement was performed 6 months after surgery at the same time as the removal of the membrane. Furthermore, a biopsy sample from the grafted sites was collected to conduct a histological analysis of the regenerated bone. Forty-seven dental implants were placed and followed up after prosthetic loading. Seventeen sites, 8 in the maxilla and 9 in the mandible, were suitable for the GBR procedure. The healing period was uneventful in 13 sites. The average value of vertical bone regeneration was 5.88 ± 1.17 mm. Postloading follow-up ranged from 24 to 59 months. During the follow-up, clinical and radiographic exams showed no significant bone resorption and, in each case, the criteria for implants' survival were respected with no signs of any complications. Histological analysis of the bone biopsy samples revealed residual graft particulate in close contact with newly formed bone. Guided bone regeneration is a reliable technique for reconstruction of severe atrophic ridges. Larger long-term follow-up studies are needed to evaluate the condition of the bone grafted over time and its ability to support functional loading of the implants.

Comparative barrier membrane degradation over time: Pericardium versus dermal membranes

Objective

The effectiveness of GBR procedures for the reconstruction of periodontal defects has been well documented. The objective of this investigation was to evaluate the degradation kinetics and biocompatibility of two resorbable collagen membranes in conjunction with a bovine xenograft material.

Materials and Methods

Lower premolars and first molars were extracted from 18 male Yucatan minipigs. After 4 months of healing, standardized semi‐saddle defects were created (12 mm × 8 mm × 8 mm [l˙̇ × W˙ × d]), with 10 mm between adjacent defects. The defects were filled with a bovine xenograft and covered with a either the bilayer collagen membrane (control) or the porcine pericardium‐derived collagen membrane (test). Histological analysis was performed after 4, 8, and 12 weeks of healing and the amount of residual membrane evaluated. Non‐inferiority was calculated using the Brunner‐Langer mixed regression model.

Results

Histological analysis indicated the presence of residual membrane in both groups at all time points, with significant degradation noted in both groups at 12 weeks compared to 4 weeks (p = .017). No significant difference in ranked residual membrane scores between the control and test membranes was detected at any time point.

Conclusions

The pericardium‐derived membrane was shown to be statistically non‐inferior to the control membrane with respect to resorption kinetics and barrier function when utilized for guided bone regeneration in semi‐saddle defects in minipigs. Further evaluation is necessary in the clinical setting.

Simultaneous implant placement with autogenous onlay bone grafts: a systematic review and meta-analysis

Several authors have suggested that implants can be placed simultaneously with onlay bone grafts without affecting outcomes. Therefore, the purpose of this study was to answer the following clinical questions: (1) What are the outcomes of implants placed simultaneously with autogenous onlay bone grafts? And (2) is there a difference in outcomes between simultaneous vs delayed placement of implants with autogenous onlay bone grafts? Databases of PubMed, Embase, and Google Scholar were searched up to 15 November 2020. Data on implant survival was extracted from all the included studies (single arm and comparative) to calculate point estimates with 95% confidence intervals (CI) and pooled using the DerSimonian–Laird meta-analysis model. We also compared implant survival rates between the simultaneous and delayed placement of implants with data from comparative studies. Nineteen studies were included. Five of them compared simultaneous and delayed placement of implants. Dividing the studies based on follow-up duration, the pooled survival of implant placed simultaneously with onlay grafts after <2.5 years of follow-up was 93.1% (95% CI 82.6 to 97.4%) and after 2.5–5 years was 86% (95% CI 78.6 to 91.1%). Implant survival was found to be 85.8% (95% CI 79.6 to 90.3%) with iliac crest grafts and 95.7% (95% CI 83.9 to 93.0%) with intra-oral grafts. Our results indicated no statistically significant difference in implant survival between simultaneous and delayed placement (OR 0.43, 95% 0.07, 2.49, I²=59.04%). Data on implant success and bone loss were limited. Data indicates that implants placed simultaneously with autogenous onlay grafts have a survival rate of 93.1% and 86% after a follow-up of <2.5 years and 2.5–5years respectively. A limited number of studies indicate no significant difference in implant survival between the simultaneous and delayed placement of implants with onlay bone grafts. There is a need for randomized controlled trials comparing simultaneous and delayed implant placement to provide robust evidence.

Matrix stiffening by self-mineralizable guided bone regeneration

Collagen membranes produced in vitro with different degrees of intrafibrillar mineralization are potentially useful for guided bone regeneration (GBR). However, highly-mineralized collagen membranes are brittle and difficult for clinical manipulation. The present study aimed at developing an intrafibrillar self-mineralization strategy for GBR membrane by covalently conjugating high-molecular weight polyacrylic acid (HPAA) on Bio-Gide® membranes (BG). The properties of the self-mineralizable membranes (HBG) and their potential to induce bone regeneration were investigated. The HBG underwent the progressive intrafibrillar mineralization as well as the increase in stiffness after immersed in supersaturated calcium phosphate solution, osteogenic medium, or after being implanted into a murine calvarial bone defect. The HBG promoted in-situ bone regeneration via stimulating osteogenic differentiation of mesenchymal stromal cells (MSCs). Hippo signaling was inhibited when MSCs were cultured on the self-mineralized HBG, and in HBG-promoted MSC osteogenesis during in-situ bone regeneration. This resulted in translocation of the transcription co-activators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) into the nucleus to induce transcription of genes promoting osteogenic differentiation of MSCs. Taken together, these findings indicated that HBG possessed the ability to self-mineralize in situ via intrafibrillar mineralization. The increase in stiffness of the extracellular matrix expedited in-situ bone regeneration by inactivating the Hippo-YAP/TAZ signaling cascade. STATEMENT OF SIGNIFICANCE: Guided bone regeneration (GBR) membranes made of naturally derived collagen have been widely used in the bone defect restoration. However, application of collagen GBR membranes run into the bottleneck with the challenges like insufficient stress strength, relatively poor dimensional stability and unsatisfactory osteoinductivity. This study develops a modified GBR membrane that can undergo progressive self-mineralization and matrix stiffening in situ. Increase in extracellular matrix stiffness provides the mechanical cues required for MSCs differentiation and expedites in-situ bone regeneration by inactivating the Hippo-YAP/TAZ signaling cascade.

Critical-size Defect Augmentation Using Sintered and Non-Sintered Bovine Bone Matrix - An Experimental Controlled Study in Minipigs

PURPOSE

Xenogeneic bone substitute materials are often used for augmentation of larger bone defects. Purification methods for these materials vary, mainly in terms of temperature. The aim of this study was to determine in vivo how sintering affects quantitative and qualitative bone regeneration of 2 bovine augmentation materials.

METHODS

A total of 56 critical size defects were set at the frontal bone of 14 domestic pigs (4 each) and filled randomly with either bovine, sintered hydroxyapatite (BO), bovine, non-sintered hydroxyapatite (BOS), local autologous bone (AB) or left empty. All defects were additionally covered with a collagen membrane. Specimens were harvested after 4 and 8 weeks and were evaluated histologically and histomorphometrically.

RESULTS

Histologically new bone could be seen in every group. Significantly highest new bone formation was found in AB. No significant difference could be detected between BO and BOS.

CONCLUSIONS

According to the results of this study, sintered bone substitute material remains histologically distinguishable but does not affect quantitative and qualitative bone regeneration.

Titanium Meshes in Guided Bone Regeneration: A Systematic Review

The presence of satisfactory bone volume is fundamental for the achievement of osseointegration. This systematic review aims to analyse the use of titanium meshes in guided bone regeneration in terms of bone gain, survival and success rates of implants, and percentages of exposure. An electronic search was conducted Articles were selected from databases in MEDLINE (PubMed), SCOPUS, Scielo, and Cochrane Library databases to identify studies in which bone regeneration was performed through particulate bone and the use of titanium meshes. Twenty-one studies were included in the review. In total, 382 patients, 416 titanium meshes, and 709 implants were evaluated. The average bone gain was 4.3 mm in horizontal width and 4.11 mm in vertical height. The mesh exposure was highly prevalent (28%). The survival rate of 145 simultaneous implants was 99.5%; the survival rate of 507 delayed implants was 99%. The success rate of 105 simultaneous implants was 97%; the success rate of 285 delayed implants was 95.1%. The clinical studies currently available in the literature have shown the predictability of this technique. It has a high risk of soft tissue dehiscence and membrane exposure although the optimal management of membrane exposition permits obtaining a sufficient bone regeneration volume and prevents compromising the final treatment outcome.

Influence of different carrier materials on biphasic calcium phosphate induced bone regeneration

OBJECTIVES

Biphasic calcium phosphate (BCP) is a bioceramic material successfully used in alloplastic bone augmentation. Despite many advantages, a disadvantage of BCP seems to be a difficult application and position instability. The aim of this study was to determine how different carrier materials influence BCP-induced quantitative and qualitative bone regeneration.

MATERIALS AND METHODS

A total of 70 critical size defects were set in the frontal bone of 14 domestic pigs (5 each) and filled randomly with either BCP alone (BCP), BCP in combination with nano-hydroxyapatite (BCP + NHA), BCP embedded in native porcine type I/III collagen blocks (BCP + C), autologous bone (AB), or were left empty (ED). Specimens were harvested after 4 and 8 weeks and were evaluated histologically as well as histomorphometrically.

RESULTS

Significantly lowest rate of new bone formation was found in ED (p = < 0.001) and BCP + NHA groups (p = 0.05). After 8 weeks, the highest percentage of new bone formation was observed in the BCP + C group. Fibrous matrix was detected highest in BCP alone. The lowest residual bone substitute material was found in BCP + C after 8 weeks.

CONCLUSIONS

BCP-induced bone regeneration is indeed affected by different carrier types. Surface morphology and bioactive characteristics influence osseointegration and new bone formation in vivo. The combination of type I/III collagen seems most suitable for qualitative and quantitative bone regeneration.

CLINICAL RELEVANCE

Stabilization of granular bone substitutes using type I/III collagen might be an alternative to granulates alone, indicating excellent volume stability, satisfactory plasticity, and easy application.

In vitro degradation, biocompatibility and antibacterial properties of pure zinc: assessing the potential of Zn as a guided bone regeneration membrane

Membrane exposure is a common complication after the guided bone regeneration (GBR) procedure and has a detrimental influence on the bone regeneration outcomes, while the commercially available GBR membranes show limited exposure tolerance. Recently, zinc (Zn) has been suggested as a promising material to be used as a barrier membrane in GBR therapy for bone augmentation. In this study, the degradation behavior in artificial saliva solution, cytotoxicity and antibacterial activity of pure Zn were investigated to explore its degradation and associated biocompatibility in the case of premature membrane exposure. The results indicated that the degradation rate of Zn in artificial saliva solution was about 31.42 μm year-1 after 28 days of immersion. The corrosion products on the Zn surface were mainly composed of Zn3(PO4)2, Ca3(PO4)2, CaHPO4, Zn5(CO3)2(OH)6 and ZnO. Besides, Zn presented an acceptable in vitro HGF cytocompatibility and a high antibacterial activity against Porphyromonas gingivalis. The preliminary results demonstrate that pure Zn exhibits appropriate degradation behavior, adequate cell compatibility and favorable antibacterial properties in the oral environment and is thus believed to sustain profitable function when membrane exposure occurs. The results provided new insights for understanding the exposure tolerance of Zn based membranes and are beneficial to their clinical applications.

Implant survival and risk factor analysis in regenerated bone: results from a 5-year retrospective study

Purpose

The aims of this study were to evaluate the 5-year cumulative survival rate (CSR) of implants placed with guided bone regeneration (GBR) compared to implants placed in native bone, and to identify factors contributing to implant failure in regenerated bone.

Methods

This retrospective cohort study included 240 patients who had implant placement either with a GBR procedure (regenerated bone group) or with pristine bone (native bone group). Data on demographic features (age, sex, smoking, and medical history), location of the implant, implant-specific features, and grafting procedures and materials were collected. The 5-year CSRs in both groups were estimated using Kaplan-Meier analysis. Risk factors for implant failure were analyzed with a Cox proportional hazards model.

Results

In total, 264 implants in the native bone group and 133 implants in the regenerated bone group were analyzed. The 5-year CSRs were 96.4% in the regenerated bone group and 97.5% in the native bone group, which was not a significant difference. The multivariable analysis confirmed that bone status was not an independent risk factor for implant failure. However, smoking significantly increased the failure rate (hazard ratio, 10.7; P=0.002).

Conclusions

The 5-year CSR of implants placed in regenerated bone using GBR was comparable to that of implants placed in native bone. Smoking significantly increased the risk of implant failure in both groups.

Accuracy of virtual planning in orthognathic surgery: a systematic review

BACKGROUND

The elaboration of a precise pre-surgical plan is essential during surgical treatment of dentofacial deformities. The aim of this study was to evaluate the accuracy of computer-aided simulation compared with the actual surgical outcome, following orthognathic surgery reported in clinical trials.

METHODS

Our search was performed in PubMed, EMBASE, Cochrane Library and SciELO for articles published in the last decade. A total of 392 articles identified were assessed independently and in a blinded manner using eligibility criteria, out of which only twelve articles were selected for inclusion in our research. Data were presented using intra-class correlation coefficient, and linear and angular differences in three planes.

RESULTS

The comparison of the accuracy analyses of the examined method has shown an average translation (< 2 mm) in the maxilla and also in the mandible (in three planes). The accuracy values for pitch, yaw, and roll (°) were (< 2.75, < 1.7 and < 1.1) for the maxilla, respectively, and (< 2.75, < 1.8, < 1.1) for the mandible. Cone-beam computed tomography (CBCT) with intra-oral scans of the dental casts is the most used imaging protocols for virtual orthognathic planning. Furthermore, calculation of the linear and angular differences between the virtual plan and postoperative outcomes was the most frequented method used for accuracy assessment (10 out of 12 studies) and a difference less than 2 mm/° was considered acceptable and accurate. When comparing this technique with the classical planning, virtual planning appears to be more accurate, especially in terms of frontal symmetry.

CONCLUSION

Virtual planning seems to be an accurate and reproducible method for orthognathic treatment planning. However, more clinical trials are needed to clearly determine the accuracy and validation of the virtual planning in orthognathic surgery.

A New Polycaprolactone-Based Biomembrane Functionalized with BMP-2 and Stem Cells Improves Maxillary Bone Regeneration

Oral diseases have an impact on the general condition and quality of life of patients. After a dento-alveolar trauma, a tooth extraction, or, in the case of some genetic skeletal diseases, a maxillary bone defect, can be observed, leading to the impossibility of placing a dental implant for the restoration of masticatory function. Recently, bone neoformation was demonstrated after in vivo implantation of polycaprolactone (PCL) biomembranes functionalized with bone morphogenic protein 2 (BMP-2) and ibuprofen in a mouse maxillary bone lesion. In the present study, human bone marrow derived mesenchymal stem cells (hBM-MSCs) were added on BMP-2 functionalized PCL biomembranes and implanted in a maxillary bone lesion. Viability of hBM-MSCs on the biomembranes has been observed using the "LIVE/DEAD" viability test and scanning electron microscopy (SEM). Maxillary bone regeneration was observed for periods ranging from 90 to 150 days after implantation. Various imaging methods (histology, micro-CT) have demonstrated bone remodeling and filling of the lesion by neoformed bone tissue. The presence of mesenchymal stem cells and BMP-2 allows the acceleration of the bone remodeling process. These results are encouraging for the effectiveness and the clinical use of this new technology combining growth factors and mesenchymal stem cells derived from bone marrow in a bioresorbable membrane.

Coating doxycycline on titanium-based implants: Two in vivo studies

Regardless of the substantial progress in designing titanium-based dental implants and aseptic techniques, infection remains as the most common complication after implantation surgeries. Although, having a weakened immune system or systematic diseases is not seen as contraindicated for dental implants anymore, controlling the immune system is required to avoid surgical site infections after implantation. These patients have to control the surgical site infections by taking a high daily dose of oral antibiotics after dental implantation. The antibiotics oral administration has many side effects such as gastrointestinal symptoms, skin rashes and thrush. Coating antibiotics on the biomaterials surface could be a promising solution to reduce these disadvantages through locally releasing antibiotics in a controlled manner. The aim of this study was to investigate the effects of doxycycline coating layer on titanium-zirconium alloy surfaces in vitro and in vivo. In our previous studies, we demonstrated the chemical presence of doxycycline layer in vitro. In this study, we examined its physical presence using field emission scanning electron microscope and confocal microscope. We also analyzed its controlled released manner using Nano-Drop UV Vis spectrometer. After in vitro characterization of the coating layer, we evaluated its effects on the implant osseointegration in dogs and rabbits. The histological and histomorphometrical results exhibited no significant difference between doxycycline coated and uncoated groups regarding the implants osseointegration and biocompatibility for dental applications. Therefore, coating a doxycycline layer on TiZr implants could be favorable for reducing or removing the antibiotics oral administration after the implantation surgery.

Long-term clinical and radiographic results after treatment or no treatment of small buccal bone dehiscences at posterior dental implants: A randomized, controlled clinical trial

AIM

To test whether or not buccal vertical bone dehiscences (≤5 mm) around posterior implants left for spontaneous healing (SH) result in the same clinical and radiologic outcome as dehiscences treated with guided bone regeneration (GBR) at 7.5 years after implant placement (IMPL).

MATERIALS AND METHODS

Twenty-two patients receiving 28 posterior implants with a small non-contained buccal bone dehiscence (≤5 mm) were randomly assigned to the SH or the GBR group. Implants were loaded at 6 months. Clinical parameters (probing depths, sulcus bleeding index, plaque index) and approximal marginal radiographic bone levels were assessed regularly up to at least 6.8 years. The vertical extension of the dehiscences was measured clinically at IMPL and abutment connection and radiographically on cone beam computed tomographys at a mean follow-up time of 7.5 years.

RESULTS

Twenty patients with a total of 26 implants were recalled at 7.5 years (9.1% dropout). The implant/crown survival rates were 100% in both groups. Stable peri-implant tissues were observed in both groups showing only minimal signs of inflammation. During the entire study period (IMPL-7.5-year follow-up), the median buccal vertical bone gain measured 1.61 mm for the GBR group and 0.62 for the SH group showing no significant difference between the groups. Also, at 7.5 years, the median approximal marginal bone levels (GBR: 0.53; SH: 0.68) were not significantly different between the two groups (p = .61) while the remaining median buccal vertical dehiscences were larger in the SH group (2.51 mm) compared to the GBR group (1.66 mm; p = .02).

CONCLUSIONS

Implants with small non-contained buccal bone dehiscences exhibited high implant survival rates and healthy peri-implant tissues at 7.5 years. In the GBR group, the buccal vertical bone levels were higher compared to the SH group but remained stable over the entire study period for both treatments.

Changes of radiopacity around implants of different lengths: Five-year follow-up data of a randomized clinical trial

OBJECTIVE

To follow-up the radiographic changes in peri-implant bone of short (6 mm, test group) and long (10 mm, control group) single-unit implants five years after loading.

MATERIALS AND METHODS

Forty-three implants of the test and 44 implants of the control group could be reassessed from 96 originally included implants. Standardized areas of interest (AOI) were defined in the peri-implant bone at pre-defined locations at mid-length on both sides of the implants, and at the apex. An arbitrary mean grey scale value (GSV) was calculated for the AOI after brightness calibration of the radiographs. Changes for GSV were calculated and tested for possible inter- and intra-group differences using the Mann-Whitney and Wilcoxon tests.

RESULTS

The calculated intra-group differences between baseline and 5 years in the test group accounted for 2.4 ± 19.6 (i.e. slight brightening) and -6.2 ± 20.2 for the control group (i.e. slight shading), which resulted in a statistically significant difference in GSV change (p < .05). Crown-to-implant ratio was the only parameter showing an effect on GSV change (p = .001).

CONCLUSIONS

Assessing conventional radiographs, longer implants showed a slightly stronger change of radiopacity of the peri-implant bone (slight loss of density) than short ones (slightly enhanced density) after five years of loading.

Effects of argon plasma treatment on the osteoconductivity of bone grafting materials

BACKGROUND

The osteoconductive properties of bone grafting materials represent one area of research for the management of bony defects found in the fields of periodontology and oral surgery. From a physico-chemical aspect, the wettability of the graft has been demonstrated to be one of the most important factors for new bone formation. It is also well-known that argon plasma treatment (PAT) and ultraviolet irradiation (UV) may increase the surface wettability and, consequently, improve the regenerative potential of the bone grafts. Therefore, the aim of the present in vitro study was to evaluate the effect of PAT and UV treatment on the osteoconductive potential of various bone grafts.

MATERIALS AND METHODS

The following four frequently used bone grafts were selected for this study: synthetic hydroxyapatite (Mg-HA), biphasic calcium phosphate (BCP), cancellous and cortical xenogenic bone matrices (CaBM, CoBM). Sixty-six serially numbered disks 10 mm in diameter were used for each graft material and randomly assigned to the following three groups: test 1 (PAT), test 2 (UV), and control (no treatment). Six samples underwent topographic analysis using SEM pre- and post-treatments to evaluate changes in surface topography/characteristics. Additionally, cell adhesion and cell proliferation were evaluated at 2 and 72 h respectively following incubation in a three-dimensional culture system utilizing a bioreactor. Furthermore, the effects of PAT and UV on immune cells were assessed by measuring the viability of human macrophages at 24 h.

RESULTS

The topographic analysis showed different initial morphologies of the commercial biomaterials (e.g., Mg-HA and BCP showed flat morphology; BM samples were extremely porous with high roughness). The surface analysis following experimental treatments did not demonstrate topographical difference when compared with controls. Investigation of cells demonstrated that PAT treatment significantly increased cell adhesion of all 4 evaluated bone substitutes, whereas UV failed to show any statistically significant differences. The viability test revealed no differences in terms of macrophage adhesion on any of the tested surfaces.

CONCLUSION

Within their limitations, the present results suggest that treatment of various bone grafting materials with PAT appears to enhance the osteoconductivity of bone substitutes in the early stage by improving osteoblast adhesion without concomitantly affecting macrophage viability.

CLINICAL RELEVANCE

Treatment of bone grafts with PAT appears to result in faster osseointegration of the bone grafting materials and may thus favorably influence bone regeneration.

Cell-Based Therapies for Alveolar Bone and Periodontal Regeneration: Concise Review

Current regenerative strategies for alveolar bone and periodontal tissues are effective and well adopted. These are mainly based on the use of a combination of synthetic/natural scaffolds and bioactive agents, obviating the incorporation of cells. However, there are some inherent limitations associated with traditional techniques, and we hypothesized that the use of cell-based therapies as part of comprehensive regenerative protocols may help overcome these hurdles to enhance clinical outcomes. We conducted a systematic review of human controlled clinical trials investigating the clinical and/or histological effect of the use of cell-based therapies for alveolar bone and periodontal regeneration and explored the translational potential of the different cell-based strategies identified in the included trials. A total of 16 studies (11 randomized controlled trials, 5 controlled clinical trials) were included for data synthesis and qualitative analysis with meta-analyses performed when appropriate. The results suggest a clinical benefit from the use of cell therapy. Improved outcomes were shown for alveolar ridge preservation, lateral ridge augmentation, and periodontal regeneration. However, there was insufficient evidence to identify best-performing treatment modalities amongst the different cell-based techniques. In light of the clinical and histological outcomes, we identify extraction socket and challenging lateral and vertical bone defects requiring bone block grafts as strong candidates for the adjuvant application of mesenchymal stem cells. Given the complexity, invasiveness, and costs associated with techniques that include "substantial manipulation" of tissues and cells, their additional clinical benefit when compared with "minimal manipulation" must be elucidated in future trials. Stem Cells Translational Medicine 2019;8:1286&1295.

Horizontal Ridge Augmentation and Contextual Implant Placement with a Resorbable Membrane and Particulated Anorganic Bovine Bone-Derived Mineral

Alveolar ridge deficiency is considered a major limitation for successful implant placement. Various approaches have been developed to horizontal augmentation of bone volume. This case report presents the medium-term results of one-stage guided bone augmentation using an anorganic bovine bone (70%) and autologous bone (30%), placed in layers, in association with resorbable collagen membrane for a subsequent implant placement. The patient presented with a localized horizontal ridge defect in the posterior zone of the jaw. The clinical and radiographic presentations, as well as relevant literature, are presented.

Supplemental periodontal regeneration by vertical ridge augmentation around dental implants. A preclinical in vivo experimental study

OBJECTIVES

To evaluate the supplemental periodontal regeneration on adjacent teeth by vertical ridge augmentation around dental implants.

MATERIAL AND METHODS

The second premolar and the fourth premolar were extracted from both sides of the mandible in four beagle dogs. After 2 months, defects of 3 mm and 5 mm deep were formed. In the test group, vertical ridge augmentation was performed around a dental implant, and in the control group, vertical ridge augmentation was performed without implant placement. The animals were euthanized 3 months after the procedure, and radiographic and histomorphometric analyses were performed.

RESULTS

Overall, the test group showed better results than the control group. The presence of new cementum in the histological examination of the test group confirmed that vertical ridge augmentation with proper space maintaining could contribute to periodontal regeneration of adjacent teeth. Statistically significant difference in new bone height (%) was found in group I (5-mm defect depth and implant placement, GBR) when compared with group III (5-mm defect depth, GBR) and IV (3-mm defect depth, GBR). New bone area (%) was statistically different between groups I and IV.

CONCLUSIONS

In conclusion, within the limitation of this study using mandibular residual ridges after extraction of a single tooth in dogs, grafted space was maintained by dental implants better in the deep defect (5-mm depth) than the shallow defect (3-mm depth). Vertical ridge augmentation around dental implants also promoted neighboring periodontal regeneration.

Factors influencing the long-term prognosis of root tip resected teeth

Introduction: The aim of the study was to investigate possible predictive factors influencing the long-term success of root tip resection. Methods: The retrospective study included 216 patients (♂ 111, ♀ 106, median age 43.3 years). A total of 261 root tip resections were performed on these patients between 1989 and 2012. In addition to determining the success rates 5 and 10 years postoperatively, the factors gender, age, tooth type, use of bone replacement material and preoperative periodontal tooth status were examined with regard to their significance for the long-term prognosis of root tip resected teeth. Results: The evaluation showed an average success rate of 63.6% for all included teeth over the entire observation period (tooth at least one year postoperatively still in situ). The 5-year success rate was 78.2%, the 10-year success rate 63.1%. A dependence of the success rates on the tooth type could not be evaluated. However, the examination showed a clear dependence of the success on the age of the patients. Root tip resections in patients in the age group 60 years and older had significantly worse success rates compared to the age groups 20 to 39 years and 40 to 59 years. The prognosis was also significantly better for patients in the age group 20 to 39 years than for patients in the age group 40 to 59 years. Periodontally compromised teeth showed only a tendency for a poorer prognosis than periodontally healthy teeth. With regard to sex and intraoperative filling of the resection defect with bone replacement material, no differences in the success rates were found. Conclusions: A root tip resection is a good option, largely independent of the type of tooth, to preserve a tooth in the medium to long term after unsuccessful endodontic treatment. However, a revision of the endodontic treatment or even an extraction with subsequent implantation should always be considered as an alternative, especially with increasing age.

Enhanced osteogenesis and angiogenesis by PCL/chitosan/Sr-doped calcium phosphate electrospun nanocomposite membrane for guided bone regeneration

Membranes play pivotal role in guided bone regeneration (GBR) technique for reconstruction alveolar bone. GBR membrane that is able to stimulate both osteogenic and angiogenic differentiation of cells may be more effective in clinic practice. Herein, we fabricated the Sr-doped calcium phosphate/polycaprolactone/chitosan (Sr-CaP/PCL/CS) nanohybrid fibrous membrane by incorporating 20 wt% bioactive Sr-CaP nanoparticles into PCL/CS matrix via one-step electrospinning method, in order to endow the membrane with stimulation of osteogenesis and angiogenesis. The physicochemical properties, mechanical properties, Sr²⁺ release behavior, and the membrane stimulate bone mesenchymal stem cell (BMSCs) differentiation were evaluated in comparison with PCL/CS and CaP/PCL/CS membranes. The SEM images revealed that the nanocomposite membrane mimicked the extracellular matrix structure. The release curve presented a 28-day long continuous release of Sr²⁺ and concentration which was certified in an optimal range for positive biological effects at each timepoint. The in vitro cell culture experiments certified that the Sr-CaP/PCL/CS membrane enjoyed excellent biocompatibility and remarkably promoted rat bone mesenchymal stem cell (BMSCs) adhesion and proliferation. In terms of osteogenic differentiation, BMSCs seeded on the Sr-CaP/PCL/CS membrane showed a higher ALP activity level and a better matrix mineralization. What's more, the synergism of the Sr²⁺ and CaP from the Sr-CaP/PCL/CS membrane enhanced BMSCs angiogenic differentiation, herein resulting in the largest VEGF secretion amount. Consequently, the Sr-CaP/PCL/CS nanohybrid electrospun membrane has promising applications in GBR.

Effectiveness of Different Commercial Chlorhexidine-Based Mouthwashes After Periodontal and Implant Surgery: A Systematic Review

OBJECTIVES

The aim of the present study was to review the effectiveness, side effects, and patient acceptance of different concentrations and formulation of chlorhexidine-based mouthwashes used after periodontal and implant surgery.

MATERIALS AND METHODS

The PRISMA guideline was adopted in the search strategy using electronic databases PubMed and MEDLINE to identify randomized and case-control prospective studies on humans written in English language and published up to September 2017.

RESULTS

A total of 10 articles were selected for a total of 344 patients. Because of the significant heterogeneity of the outcome measures, meta-analysis was not performed, and the data were summarized in a table. A positive relationship between the use of chlorhexidine and reduction of plaque was found, demonstrating the effectiveness of the substance in terms of antisepsis and decrease of inflammation after periodontal and implant surgery.

CONCLUSION

Chlorhexidine is recognized as the primary agent for plaque control and the gold standard in preventing infection, although the presence of largely known side effects would affect patient compliance. Future research should be directed at finding chlorhexidine formulation with negligible adverse effects, without compromising or even increasing its effectiveness as the antiseptics and antiplaque agent.

Barrier membranes: More than the barrier effect?

AIM

To review the knowledge on the mechanisms controlling membrane-host interactions in guided bone regeneration (GBR) and investigate the possible role of GBR membranes as bioactive compartments in addition to their established role as barriers.

MATERIALS AND METHODS

A narrative review was utilized based on in vitro, in vivo and available clinical studies on the cellular and molecular mechanisms underlying GBR and the possible bioactive role of membranes.

RESULTS

Emerging data demonstrate that the membrane contributes bioactively to the regeneration of underlying defects. The cellular and molecular activities in the membrane are intimately linked to the promoted bone regeneration in the underlying defect. Along with the native bioactivity of GBR membranes, incorporating growth factors and cells in membranes or with graft materials may augment the regenerative processes in underlying defects.

CONCLUSION

In parallel with its barrier function, the membrane plays an active role in hosting and modulating the molecular activities of the membrane-associated cells during GBR. The biological events in the membrane are linked to the bone regenerative and remodelling processes in the underlying defect. Furthermore, the bone-promoting environments in the two compartments can likely be boosted by strategies targeting both material aspects of the membrane and host tissue responses.

Implant fracture failure rate and potential associated risk indicators: An up to 12-year retrospective study of implants in 5,124 patients

OBJECTIVES

This study investigated fracture rates and risk indicators for fractures in internal connection dental implants.

MATERIAL AND METHODS

We performed a retrospective analysis of 19,006 internal connection implants used in fixed restoration in 5,124 patients (4,570 males, 554 females) at the Dental Hospital of Veterans Health Service Medical Center between 2006 and 2015. Patients were followed through June 2018 (0.03-12.39 years post-installation). Clinical factors (age, sex, implant diameter, implant length, placement site, bone graft, fixture material, cervical feature, abutment connection, microthread, and platform switching) were recorded. Kaplan-Meier survival analysis identified risk indicators associated with an implant fracture. Cox regression models elucidated potential fracture risks.

RESULTS

One hundred and seventy-four implants fractured in 135 patients, for an incidence rate of 0.92% after an average of 4.95 ± 2.14 years of use. Kaplan-Meier estimates showed that the 3-, 5-, and 10-year survival rates of implants were 99.8%, 99.2%, and 97.7%, respectively. In the multivariable Cox regression model, the diameter, location, history of bone graft, and microthread presence were significantly correlated with implant fractures. Wide-diameter implants had a reduced fracture risk within 90 months, after which the diameter did not correlate with fractures. Implants placed in the anterior mandible had a lower fracture risk within 90 months; mandibular premolar implants corresponded with a lower risk after 90 months. Implants without a history of bone graft or microthreads were more likely to fracture throughout the follow-up time.

CONCLUSIONS

These results elucidate risk indicators for implant fractures and facilitate their reduction in clinical practice.

Quality assessment of systematic reviews on vertical bone regeneration

The aim of this study was to evaluate and compare the quality of systematic reviews of vertical bone regeneration techniques, using two quality-assessment tools (AMSTAR and ROBIS). An electronic literature search was conducted to identify systematic reviews or meta-analyses that would evaluate at least one of the following outcomes: implant survival, success rates, complications or bone gain after vertical ridge augmentation. Methodological quality assessment was performed by two independent evaluators. Results were compared between reviewers, and reliability measures were calculated using the Holsti's method^® and Cohen's kappa. Seventeen systematic reviews were included, of which seven presented meta-analysis. Mean ±95% confidence interval AMSTAR score was 6.35 [4.74;7.97], with higher scores being correlated with a smaller risk of bias (Pearson's correlation coefficient=-0.84; P<0.01). Cohen's inter-examiner kappa showed substantial agreement for both checklists. From the available evidence, we ascertained that, regardless of the technique used, it is possible to obtain vertical bone gains. Implant success in regenerated areas was similar to implants placed in pristine bone with results equating between 61.5% and 100% with guided bone regeneration being considered the most predictable technique regarding bone stability, while distraction osteogenesis achieved the biggest bone gains with the highest risk of possible complications.