Comparison between flapless and open-flap implant placement: a systematic review and meta-analysis

No consensus has been reached regarding the influence of the flapless and open-flap surgical techniques on the placement of dental implants. This systematic review compared the effects of flapless implant placement and implant placement with elevation of the mucoperiosteal flap in terms of marginal bone loss, implant survival rate and complications rates. This review followed PRISMA guidelines and was registered in PROSPERO with the registration number CRD42017071475. Two independent reviewers performed a comprehensive search of the PubMed/MEDLINE, Scopus, and Cochrane Library databases for studies published until December 2017. The search identified 559 references. After a detailed review, 24 studies were assessed for eligibility. A total of 1025 patients who had received a total of 1873 dental implants were included. There were no significant differences between the flapless and open-flap surgical techniques in terms of implant survival rates (P = 0.34; risk ratio (RR): 1.36; confidence interval (CI): 0.72–2.56), marginal bone loss (P = 0.23; MD: −0.20; CI: −0.52–0.13), or complication rates (P = 0.67; RR: 1.10; CI: 0.70–1.73). The current meta-analysis showed that the implant survival rate, marginal bone levels, and complications of flapless surgery were similar to those of open-flap surgery over a mean follow-up period of 21.62 months.     

Narrow-diameter implants versus regular-diameter implants for rehabilitation of the anterior region: a systematic review and meta-analysis

The aim of this systematic review and meta-analysis was to evaluate studies comparing implant survival rates, marginal bone loss (MBL), and mechanical and biological complication rates between narrow-diameter implants (NDIs) and regular-diameter implants (RDIs) used for oral rehabilitation in the anterior region. The review was conducted according to the PRISMA checklist. Two independent reviewers performed a comprehensive search of the PubMed/MEDLINE, Embase, Scopus, and Cochrane Library databases for studies published until May 2020. A total of 843 implants (484 NDIs and 359 RDIs) were included. No significant difference in implant survival rate (risk difference (RD) 0.01, 95% confidence interval (CI) ?0.01 to 0.03; P = 0.34), MBL (standardised mean difference ?0.51 mm, 95% CI ?1.29 to 0.26 mm; P = 0.19), mechanical complications (RD 0.01, 95% CI ?0.02 to 0.04; P = 0.40), or biological complications (RD 0.01, 95% CI ?0.09 to 0.11; P = 0.85) was found between the implant groups. Within the limitations of this study, it is concluded that NDIs are an effective alternative to RDIs due to similar survival rates, MBL, and mechanical and biological complication rates. However, future studies are highly encouraged due to the small number of interventional studies on this topic.     

Dental implants in patients with osteoporosis: a systematic review with meta-analysis

There is currently no consensus regarding the survival rate of osseointegrated implants in patients with osteoporosis. A systematic review with meta-analysis was performed to evaluate the survival rate of implants in such patients. The PubMed/MEDLINE, Web of Science, Cochrane Library, and SciELO databases were used to identify articles published up to September 2016. The systematic review was performed in accordance with PRISMA/PICO requirements and the risk of bias was assessed (Australian National Health and Medical Research Council scale). The relative risk (RR) of implant failure and mean marginal bone loss were analyzed within a 95% confidence interval (CI). Fifteen studies involving 8859 patients and 29,798 implants were included. The main outcome of the meta-analysis indicated that there was no difference in implant survival rate between patients with and without osteoporosis, either at the implant level (RR 1.39, 95% CI 0.93–2.08; P = 0.11) or at the patient level (RR 0.98, 95% CI 0.50–1.89; P = 0.94). However, the meta-analysis for the secondary outcome revealed a significant difference in marginal bone loss around implants between patients with and without osteoporosis (0.18 mm, 95% CI 0.05–0.30, P = 0.005). Data heterogeneity was low. An increase in peri-implant bone loss was observed in the osteoporosis group. Randomized and controlled clinical studies should be conducted to analyze possible biases.     

Outcomes of osseointegrated implants in patients with benign and malignant pathologies of the head and neck: a 10-year single-centre study

The surgical management of head and neck pathologies involving the maxilla and mandible results in significant functional and aesthetic deficits, and ultimately reduced quality of life. Composite free flaps used for reconstruction address many of these deficits and create a foundation for the use of osseointegrated implants to support prosthetic replacement of the dentition. There are few comparative studies examining outcomes of implants in native and reconstructed bone in head and neck cancer patients. The aim of this retrospective cohort study was to compare survival rates and the effects of risk factors between implants placed in native and reconstructed bone. The Kaplan–Meier method estimated cumulative 1- and 5-year implant survival rates of 99.5% and 95% for native bone and 96% and 88% for reconstructed bone. Multivariate Cox regression found an increased risk of implant failure in reconstructed bone (hazard ratio (HR) 9.9, 95% confidence interval (CI) 3.4–29.7, P < 0.001). Subgroup analysis of the cohorts found an increased risk of failure in the reconstructed group associated with radiotherapy (HR 6.4, 95% CI 1.8–22.3, P = 0.004), current smoking (HR 23.2, 95% CI 2.7–198.6, P = 0.004), and previous smoking (HR 9.0, 95% CI 1.1–71.9, P = 0.038). There was no effect in the native bone group. Implants placed into reconstructed bone had higher rates of failure, and smoking status and radiotherapy increased the risk of implant failure.     

Vertical bone augmentation and regular implants versus short implants in the vertically deficient posterior mandible: a systematic review and meta-analysis of randomized studies

The aim of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the outcomes of short dental implants (≤7 mm) versus vertical bone augmentation followed by regular dental implants (>7 mm) in the deficient posterior mandible. In total, eight RCTs (six using interpositional sandwich grafting and two using a guided bone regeneration technique) were reported in 17 articles at different time points. In the meta-analysis of the sandwich group, the relative risk (RR) for implant loss at 1 year was in favour of short implants (RR 0.41, P = 0.02), while no significant difference was found at 3 years (RR 0.65, P = 0.43), 5 years (RR 1.08, P = 0.86), or 8 years (RR 1.53, P = 0.52). The risk of complications was in favour of short implants (RR 0.34, P = 0.0002), as was the mean difference in marginal bone resorption after 1 year (−0.09 mm, P = 0.17), 3 years (−0.32 mm, P < 0.00001), 5 years (−0.65 mm, P < 0.00001), and 8 years (−0.88, P < 0.00001). The mean residual osseointegration length of the implants was between 2.94 mm and 4.44 mm in the short implants group and between 7.97 mm and 8.62 mm in the regular implants group after 5 years. In conclusion, in the deficient atrophic posterior mandible, short implants and regular implants demonstrate comparable outcomes within the first 5 years. Patients who are fit for surgery should be informed about the risks and benefits of both options.     

Dental implant placement in alveolar cleft patients: a retrospective comparative study on clinical and aesthetic outcomes

The aim of this retrospective study was to assess the clinical and aesthetic outcomes, and patient satisfaction, following dental implant therapy in cleft patients. Implant survival, changes in marginal bone level, pocket probing depths, plaque and bleeding indices, aesthetics, and patient satisfaction were assessed in 17 alveolar cleft patients and 17 matched controls. At follow-up (mean 72.4 ± 46.4 months), one implant had been lost in the cleft group. Mean marginal bone loss at follow-up was −0.4 ± 0.4 mm in cleft patients and −0.2 ± 0.4 mm in controls. Aesthetics of the peri-implant soft tissues (pink aesthetic score) were less favourable (P = 0.025) in cleft patients (5.0 ± 1.9) than in controls (6.5 ± 1.7), while peri-implant parameters were comparable in the two groups. Overall patient satisfaction was 8.6 ± 0.9 in cleft patients and 8.9 ± 1.1 in controls (P = 0.331). In cleft patients, no difference in aesthetics was observed between patients who received additional bone augmentation at 3 months prior to implant placement and those who did not (P = 0.092). Dental implant therapy in cleft patients is associated with high implant survival, minor marginal bone loss, healthy peri-implant soft tissues, and high patient satisfaction. Only the aesthetics of the soft tissues was worse in cleft patients compared to augmented non-cleft patients.     

Clinical comparison of a xenogeneic collagen matrix versus subepithelial autogenous connective tissue graft for augmentation of soft tissue around implants

Dental implant placement is a predictable therapy for replacing teeth. Nevertheless, mechanical, biological, and aesthetic complications frequently occur. The aim of this study was to compare the clinical outcomes of a xenogeneic collagen matrix (XCM) used at the time of implant placement as an alternative to a subepithelial connective tissue graft (SCTG), for soft tissue augmentation. This was a prospective clinical trial with 12 months of follow-up. In the control group, soft tissue augmentation at the time of implant placement was performed with a SCTG, while in the test group, a XCM was employed. At 12 months postoperative, all xenografts showed no postoperative complications. In both groups, a significantly greater thickness was observed on the buccal and occlusal sides from preoperative to 3 months postoperative (P < 0.05). No statistically significant difference in pink aesthetic score (P = 0.379, 6 months postoperative) or marginal bone loss (P = 0.449 at 3 months postoperative, P = 0.778 at 6 months postoperative) was observed between the groups. Statistically significant differences in pain perceived by the patients (P < 0.0001) and the time to complete the surgical procedure (P = 0.0008) were detected. At 12 months after surgery, XCM provided similar clinical results in terms of soft tissue augmentation on the buccal and occlusal sides as compared with the SCTG.     

Clinical viability of single implant-retained mandibular overdentures: a systematic review and meta-analysis

The aim of this meta-analysis was to verify the clinical viability of single implant-retained mandibular overdentures (SIMO). An electronic search of the PubMed and Cochrane databases was performed (end date July 2017); this was supplemented by a manual search of the literature. Only prospective clinical trials and randomized controlled trials (RCTs) that evaluated SIMO with a minimum follow-up of 12 months were included. The meta-analysis was based on the Mantel–Haenszel method. Dental implant and prosthetic failure were the dichotomous outcome measures; these were evaluated through the risk ratio (RR) and odds ratio (OR), with corresponding 95% confidence intervals (CI). Of 499 articles identified, nine fulfilled the inclusion criteria. A total of 205 implants were placed in patients with a mean age of 64.1 years; the cumulative survival rate was 96.6% over a mean follow-up period of 37.3 months. The procedure used (SIMO vs. two implant-retained mandibular overdenture) did not affect dental implant failure (P = 0.45) or prosthetic failure (P = 0.65): RR 1.06 (95% CI 0.91–1.23) and RR 0.88 (95% CI 0.51–1.51), respectively; OR 2.56 (95% CI 0.27–24.39; P = 0.41) and OR 0.44 (95% CI 0.15–1.26; P = 0.13), respectively. Within the limitations of this systematic review and meta-analysis, SIMO with a complete denture as the opposing arch may be considered an alternative treatment for completely edentulous patients. However, this study also confirmed the need for more RCTs on this topic.     

Outcomes of implants placed with three different flapless surgical procedures: A systematic review

The aim of this systematic review was to evaluate the outcomes of flapless surgery for implants placed using either free-hand or guided (with or without 3D navigation) surgical methods. Literature searches were conducted to collect information on survival rate, marginal bone loss, and complications of implants placed with such surgeries. Twenty-three clinical studies with a minimum of 1 year follow-up time were finally selected and reviewed. Free-hand flapless surgery demonstrated survival rates between 98.3% and 100% and mean marginal bone loss between 0.09 and 1.40 mm at 1–4 years after implant insertion. Flapless guided surgery without 3D navigation showed survival rates between 91% and 100% and mean marginal bone loss of 0.89 mm after an observation period of 2–10 years. The survival rates and mean marginal bone loss for implants placed with 3D guided flapless surgery were 89–100% and 0.55–2.6 mm, respectively, at 1–5 years after implant insertion. In 17 studies, surgical and technical complications such as bone perforation, fracture of the surgical guide, and fracture of the provisional prosthesis were reported. However, none of the identified methods has demonstrated advantages over the others. Further studies are needed to confirm the predictability and effectiveness of 3D navigation techniques.     

Short implants (5‐8 mm) vs long implants (≥10 mm) with augmentation in atrophic posterior jaws: A meta‐analysis of randomised controlled trials

The aim of this systematic review was to compare the survival rate, marginal bone loss changes and complications between short implants (5‐8 mm) and long implants (≥10 mm) with a bone‐augmented procedure in the posterior jaw. An electronic search of the MEDLINE (PubMed), Embase and Cochrane Library databases through September 2018 was done to identify randomised controlled trials (RCT) assessing short implants and long implants with at least a 1‐year follow‐up period after loading. A quantitative meta‐analysis was conducted on the survival rate, marginal bone loss changes and complications. Ten RCTs met the inclusion criteria. There were no significant differences in the survival rate (RR: 1.01; 95% CI: [0.99, 1.03]; P = .32) and complications (RR: 0.48; 95% CI: [0.20, 1.17]; P = .11) between the two groups. Compared with the long implant group, the short implant group had a lower marginal bone loss change, and the effect measure was significant (mean difference: ?0.13; 95% CI: [?0.20, ?0.06]; P < .05). This systematic review showed no difference between the survival rates and complications of short implants (5‐8 mm) and long implants (≥10 mm). The marginal bone loss changes in short implants are lower than those in long implants.     

Efficacy of the autogenous dentin graft for implant placement: a systematic review and meta-analysis of randomized controlled trials

The aim of this study was to determine whether the autogenous dentin graft (ADG) shows comparable results and similar clinical performance to other graft materials when utilized for implant placement. Four databases were searched, and controlled human studies that applied autogenous dentin for implant surgery, comparing it with other bone grafts, were included. Nine articles met the inclusion criteria, five of which were randomized controlled trials and were included in the meta-analysis. ADG showed equivalent primary and secondary implant stability when compared to Bio-Oss (primary: mean difference −0.74, 95% confidence interval (CI) − 3.36 to 1.88, P = 0.58; secondary: mean difference − 1.29, 95% CI − 5.69 to 3.11, P = 0.57). The standardized mean difference (SMD) of marginal bone loss at 6 months and at the final follow-up (18 months) showed the two grafts to be similar (6 months: SMD −0.26, 95% CI −0.64 to 0.12, P = 0.18; final follow-up: SMD −0.12, 95% CI −0.50 to 0.26, P = 0.53), and survival after immediate implant placement was the same in the two groups: 97.37% and 97.30%, respectively. Incidences of complications with the autogenous dentin particles or blocks were in line with those of Bio-Oss or autogenous bone blocks, respectively. This meta-analysis indicates that the autogenous dentin graft is an effective option for bone augmentation around dental implants, with acceptable implant stability, marginal bone loss, and incidences of complications and failure.     

Locking versus non-locking plate fixation in the management of mandibular fractures: a meta-analysis

The aim of the present study was to test whether there is a significant difference in the clinical outcomes between locking and non-locking plate fixation in the management of mandibular fractures. An electronic search without time or language restrictions was undertaken in December 2013. Eligible studies were clinical human studies, either randomized or not. The search strategy identified 10 publications. The I² statistic was used to express the percentage of the total variation across studies due to heterogeneity. The inverse variance method was used for the random-effects model in the case of heterogeneity being detected, or the fixed-effects model in the case of heterogeneity not being detected. The estimates of an intervention were expressed as the risk ratio (RR) with 95% confidence interval. Eight studies were judged to be at high risk of bias, whereas two studies were considered at moderate risk of bias. There was no statistically significant effect on the outcome of postoperative infection (P = 0.17), malocclusion (P = 0.15), hardware failure (P = 0.77), hardware removal (P = 0.95), wound dehiscence (P = 0.98), or paraesthesia (P = 0.20) in favour of locking plate fixation. The test for overall effect showed that the difference between the procedures did not significantly affect the incidence of postoperative complications (P = 0.21), with RR 0.79 (95% CI 0.54–1.14).     

Incidence of bleeding after minor oral surgery in patients on dual antiplatelet therapy: a systematic review and meta-analysis

Bleeding is a feared complication of minor oral surgery in patients on treatment with antiplatelet agents and there is no agreed strategy regarding the cessation or not of antiplatelet treatment. The aim of this systematic review was to evaluate bleeding with minor oral surgery in patients on dual antiplatelet therapy (DAPT), single antiplatelet therapy (SAPT), or no antiplatelet therapy (no APT). The PubMed, Embase, Web of Science, and Cochrane Library databases were screened. Sixteen studies were included. DAPT was continued in all studies. The perioperative bleeding risk was significantly higher for DAPT than for SAPT (risk ratio (RR) 10.16, P =  0.010; risk difference (RD) 0.35, P =  0.269), but not higher compared to no APT (RR 6.50, P =  0.057; RD 0.19, P =  0.060). The postoperative bleeding risk was significantly elevated for DAPT compared to SAPT (RR 2.61, P =  0.010) and no APT (RR 3.63, P =  0.035), but only by 1% (RD 0.01, P =  0.103) and 1% (RD 0.01, P =  0.421), respectively. Clinically, this may be considered quite similar. Additionally, local haemostatic measures could control all reported bleeding and no lethal events occurred. Therefore, DAPT interruption is not advised before minor oral surgery.     

Clinical outcome and bone healing of implants placed with high insertion torque: 12-month results from a multicenter controlled cohort study

This study evaluated the clinical outcome and the crestal bone resorption of implants placed with high insertion torque (up to 80 N cm). 102 patients were treated with 156 tapered implants. 42 implants (control group) presented insertion torque between 30 and 45 N cm (mean = 37.4 SD 8.2). 114 implants (experimental group) were placed with insertion torque between 50 and 80 N cm (mean = 74.8 SD 7.9). All implants were early loaded after 2 months. Peri-implant marginal bone levels were assessed immediately after surgery, and at 6- and 12-month follow up examinations. At the 12-month follow up all implants were clinically stable. After 12 months, patients in the experimental group lost an average of 0.41 mm (CI 95% 0.522; 0.263) of crestal bone compared with 0.45 mm (CI 95% 0.561; 0.286) for those in the control group. There were no significant differences between the two groups. No direct or inverse relationship was observed between the insertion torque values and crestal bone resorption. The results show that the use of high insertion torque (up to 80 N cm) did not prevent osseointegration and did not increase bone resorption around tapered implants early loaded up to 1 year after implant placement.     

Effect of platelet-rich fibrin on the control of alveolar osteitis,pain, trismus,soft tissue healing,and swelling following mandibular third molar surgery: an updated systematic review and meta-analysis

The purpose of this study was to estimate the effect of platelet-rich fibrin (PRF) on the control of alveolar osteitis (AO), pain, trismus, soft tissue healing, and swelling following mandibular third molar surgery. A comprehensive search of the literature was conducted through PubMed, Embase, Web of Science, and Cochrane Library up to May 2019. Randomized controlled studies conforming to the inclusion criteria were included. The record screening and data extraction were conducted by two authors independently. The risk of bias assessment was performed according to the guidelines recommended by the Cochrane Collaboration. The quantitative analysis was performed using RevMan version 5.3. Nineteen studies were included in the systematic review and 17 studies were eligible for the meta-analysis. The use of PRF significantly reduced the incidence of AO and postoperative pain when compared to the controls (AO: relative risk 0.43, 95% confidence interval (CI) 0.28 to 0.65, Z = 3.90, P < 0.0001 (I² = 0%); pain: day 1, standardized mean difference (SMD) ?1.12, 95% CI ?1.87 to ?0.37, Z = 2.93, P = 0.003 (I² = 95%); day 3, SMD ?0.93, 95% CI ?1.48 to ?0.38, Z = 3.30, P = 0.001 (I² = 92%); day 7, SMD ?1.84, 95% CI ?2.98 to ?0.71, Z = 3.19, P = 0.001 (I² = 97%)). Additionally, the result showed a better soft tissue healing when PRF was used (mean difference ?0.63, 95% CI ?1.08 to ?0.18, Z = 2.76, P = 0.006 (I² = 90%)). The use of PRF reduced the incidence of AO and postoperative pain following third molar surgery. Furthermore, PRF may also improve the postoperative soft tissue healing.     

The impact of smoking on surgical complications after head and neck reconstructive surgery with a free vascularised tissue flap: a systematic review and meta-analysis

Reconstructive surgery with a free vascularised tissue flap is indicated in large defects in the head and neck region, which arise mostly because of head and neck cancer. Tobacco smoking is a major risk factor for head and neck cancer, and many patients undergoing reconstructive surgery in the head and neck have a history of smoking. The objective of this meta-analysis was to determine the impact of smoking on surgical complications after head and neck reconstructive surgery with a free vascularised tissue flap. A systematic review was undertaken for articles reporting and comparing the incidence of overall surgical complications after reconstructive surgery with a free vascularised tissue flap between smokers and nonsmokers. Relevant articles were searched using PubMed, Cochrane, and Embase databases, and screened for eligibility according to the PRISMA guidelines. The risk of bias analysis was conducted using the Newcastle-Ottawa quality assessment scale. A meta-analysis was performed to quantitatively compare the incidence rate of overall surgical complications, flap failure, surgical site infection, fistula, and haematoma between smokers and nonsmokers using OpenMetaAnalyst (open source) software. Only qualitative analysis was performed for wound dehiscence, bleeding, nerve injury, and impaired wound healing. Forty-six articles were screened for eligibility; 30 full texts were reviewed, and 19 studies were included in the quantitative meta-analysis. From the 19 studies, 18 were retrospective and 1 was a prospective study. In total, 2155 smokers and 3124 nonsmokers were included in the meta-analysis. Smoking was associated with a significantly increased risk of 19.12% for haematoma (95% Confidence Interval (CI): 4.75–33.49; p < 0.01), and of 4.57% for overall surgical complications (95% CI: 1.97–7.15; p < 0.01). No significant difference in risk was found for flap failure (95% CI: ?4.33–9.90; p = 0.44), surgical site infection (95% CI: ?0.88–2.60; p = 0.33) and fistula formation (95% CI: ?3.81–3.71; p = 0.98) between smokers and nonsmokers. Only for flap failure was a significant heterogeneity found (I² = 63.02%; p = 0.03). Smoking tobacco was significantly associated with an increased risk of overall surgical complications and haematoma, but did not seem to affect other postoperative complications. Encouraging smoking cessation in patients who need reconstructive head and neck surgery remains important, but delaying surgery to create a non-smoking interval is not needed to prevent the investigated complications. More high-quality retrospective or prospective studies with a standardised protocol are needed to allow for definitive conclusions.     

The efficacy of tranexamic acid for orthognathic surgery: a meta-analysis of randomized controlled trials

The efficacy of tranexamic acid in orthognathic surgery remains controversial. We conducted a systematic review and meta-analysis to explore the influence of tranexamic acid on blood loss for orthognathic surgery.We performed a search of PubMed, Embase, Web of science, EBSCO, and Cochrane library databases through October 2017 for randomized controlled trials (RCTs) assessing the effects of tranexamic acid versus placebo on orthognathic surgery. Meta-analysis was performed using the random-effects model.Six RCTs were included in the meta-analysis. Overall, compared with placebo in orthognathic surgery, tranexamic acid administration results in significantly decreased blood loss [mean difference (MD) = −159.73; 95% confidence interval (CI) = −236.42 to −83.03; P < 0.0001], and higher postoperative haemoglobin (MD = 0.71; 95% CI = 0.11 to 1.31; P = 0.02), but has no remarkable impact on postoperative haematocrit (MD = 1.23; 95% CI = −1.22 to 3.69; P = 0.33) and operation time (MD = −2.35; 95% CI = −18.05 to 13.36; P = 0.77). In addition, patients with orthognathic surgery need decreased amounts of irrigant fluid (MD = −229.23; 95% CI = −399.63 to −58.83; P = 0.008) after using tranexamic acid.We concluded that tranexamic acid promotes the bleeding control in orthognathic surgery.     

Resveratrol improves bone repair by modulation of bone morphogenetic proteins and osteopontin gene expression in rats

This study investigated the effect of resveratrol on bone healing and its influence on the gene expression of osteogenic markers. Two calvarial defects were created and one screw-shaped titanium implant was inserted in the tibia of rats that were assigned to daily administration of placebo (control group, n = 15) or 10 mg/kg of resveratrol (RESV group, n = 15) for 30 days. The animals were then sacrificed. One of the calvarial defects was processed for histomorphometric analysis and the tissue relative to the other was collected for mRNA quantification of bone morphogenetic protein (BMP)-2, BMP-7, osteopontin (OPN), bone sialoprotein (BSP), osteoprotegrin (OPG), and receptor activator of NF-κB ligand (RANKL). Implants were removed by applying a counter-torque force. Histomorphometric analysis revealed higher remaining defect in the calvarial defects of the control group than the RESV group (P = 0.026). Resveratrol increased the counter-torque values of implant removal when compared to control therapy (P = 0.031). Gene expression analysis showed a higher expression of BMP-2 (P = 0.011), BMP-7 (P = 0.049), and OPN (P = 0.002) genes in the RESV group than in the control group. In conclusion, resveratrol improved the repair of critical-sized bone defects and the biomechanical retention of implants. Indeed, this natural agent may up-regulate the gene expression of important osteogenic markers.     

Marginal bone loss one year after implantation: a systematic review of different loading protocols

The aim of this study was to analyse the influence of different loading protocols on marginal bone loss (MBL). The outcomes of different implant loading protocols were assessed at 1 year after implantation, with focus on MBL; protocols included immediate, immediate non-occlusal, early, and conventional loading. The search strategy resulted in 889 studies. Twenty-two of these studies fulfilled the inclusion criteria. Among the included studies, the lowest MBL was for immediately loaded implants (0.05 ± 0.67 mm) and the highest for immediate non-occlusally loaded implants (1.37 ± 0.5 mm). The results of the meta-analysis showed an estimated mean MBL of 0.457 mm (95% confidence interval (CI) 0.133–0.781) for immediate loading, 0.390 mm (95% CI 0.240–0.540) for immediate non-occlusal loading, 0.488 mm (95% CI 0.289–0.687) for early loading (>2 days to <3 months), and 0.852 mm (95% CI 0.429–1.275) for conventional loading (>3 months) implant protocols. The lowest decrease in 1-year implant survival per millimetre increase in MBL was observed for immediate loading and the highest for conventional loading. Conventional loading showed a significantly higher MBL than the other three loading protocols. This systematic review and meta-analysis indicates that the immediate loading protocol is a reasonable alternative to the conventional loading protocol.