Short versus standard implants at sinus augmented sites: a systematic review and meta-analysis

Clinical Oral Investigations - Short implants are proposed as a less invasive alternative with fewer complications than standard implants in combination with sinus lift. The aim of this systematic...     

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.     

Quality assessment of systematic reviews regarding immediate placement of dental implants into infected sites: An overview

Statement of problem

With the increased number of published systematic reviews and in view of their wide clinical applicability, these studies must be carefully assessed before professionals begin to use their recommendations in daily practice, and above all, the methodological quality of this study design must be considered. In implant dentistry, one topic that has been arousing particular interest is the immediate placement of dental implants into infected sites.

Clinical performance of one‐piece zirconia dental implants: A systematic review

The aim of the present review was to evaluate the clinical and radiographic performance of one‐piece zirconia implants (O‐PZI). This review followed the PRISMA (Preferred Reporting Items for Systematic Review and Meta‐Analysis) guidelines that addressed the following focused question: What is the overall clinical and radiographic performance of O‐PZI? The MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register databases were searched. Six clinical studies were included. For studies evaluating O‐PZI compared with one‐piece titanium implants, zirconia implants showed higher crestal bone loss (CBL) in both the studies. However, one study demonstrated a high failure rate compared to titanium dental implants, while one study demonstrated comparable survival rates between zirconia and titanium dental implants. For studies evaluating O‐PZI for the restoration of single crown and fixed dental prostheses, O‐PZI showed comparable bone loss and survival rates for single crowns and fixed dental prostheses. Two studies were included that compared O‐PZI with two‐piece zirconia (T‐PZI). One study showed a higher CBL and low survival rate for O‐PZI compared to T‐PZI, whereas the other study demonstrated comparable CBL and survival rates between O‐PZI and T‐PZI. It is still debatable whether O‐PZI demonstrate better clinical performance when compared with titanium implants or two‐piece design.     

Alveolar ridge preservation: an overview of systematic reviews

The aim of this overview was to assess the methodological quality of systematic reviews of randomized clinical trials on alveolar ridge preservation after a tooth extraction. During March 2020, two independent reviewers performed an electronic search of the PubMed (MEDLINE), Scopus, Web of Science, and Cochrane Library databases to identify all relevant systematic reviews including randomized clinical trials on alveolar ridge preservation. A manual search of articles in renowned journals was also conducted. The methodological quality of the included reviews was determined using the AMSTAR-2 tool. From the 53 initially retrieved studies, 11 were finally included: three systematic reviews and eight systematic reviews with meta-analyses. The methodological quality of the included reviews was low or critically low. Higher quality clinical studies should be conducted prior to performing further reviews and these should meet the methodological requirements that are fundamental to this type of research.     

Longevity of dental implants in type IV bone: a systematic review

Bone quality and quantity are important factors with regard to the survival rate of dental implants. The aim of this study was to conduct a systematic review of dental implants inserted in low-density bone and to determine the survival rate of dental implants with surface treatments over time. A systematic review of the literature was undertaken by two independent individuals; the Medline/PubMed database was searched for the period July 1975 to March 2013. Relevant reports on bone quality and osseointegration of dental implants were selected. The search retrieved 1018 references, and after inclusion and exclusion criteria were applied, 19 studies were selected for review. A total of 3937 patients, who had received a total of 12,465 dental implants, were analyzed. The survival rates of dental implants according to the bone density were: type I, 97.6%; type II, 96.2%; type III, 96.5%; and type IV, 88.8%. The survival rate of treated surface implants inserted in low-density bone was higher (97.1%) than that of machined surface implants (91.6%). Surface-treated dental implants inserted in low-density bone have a high survival rate and may be indicated for oral rehabilitation. However, more randomized studies are required to better evaluate this issue.     

Antibiotic prophylaxis in orthognathic surgery: an overview of systematic reviews

The purpose of this overview was to assess different antibiotic regimens used in orthognathic surgery and to establish an evidence-based protocol so that beneficial and adverse effects can be determined. A comprehensive literature search for systematic reviews and/or meta-analyses was conducted in MEDLINE (PubMed), EMBASE, and the Cochrane Library until March 2020. Grey literature was investigated in Google Scholar, and a manual search was done of references lists. Two meta-analyses and four systematic reviews met the inclusion criteria. The AMSTAR-2-tool was used to ascertain the potential risk of bias in the included studies, which presented moderate to high methodological quality. Lower infection rates were associated with long-term therapies of penicillin, cefazolin-cephalexin, and amoxicillin-clavulanic-acid, with rates varying from 0% - 3.13%. Higher rates were reported in placebo groups (52.6%) and short-term penicillin therapy (60%). Side effects were reported with cefazolin, clindamycin, and penicillin therapies, including nausea, pain, swelling, headache, vomiting, and skin rash. Evidence suggests that long-term antibiotics can reduce the risk of a surgical site infection (SSI) in orthognathic surgery, but there is uncertainty regarding the effects of one dose of antibiotics preoperatively versus short-term antibiotics. In the same way, intravenous penicillin, cefazolin, clindamycin, and amoxicillin-clavulanic acid kept the infection rates associated with bimaxillary procedures under 3.5%.     

短种植体在后牙区种植修复的临床观察

目的： ITI短种植体在上下颌后牙区的临床观察及效果评价。方法：选择2005年10月至2013年10月间,在我院接受上下颌后牙区短种植体手术治疗的患者26例,共31枚种植体。随访4月-8年,观察指标包括X线片、临床检查,软组织（指标：牙槽骨吸收情况、牙龈指数、探针深度）等。结果：观察期间未发现短种植体出现松动、断裂,种植部位出现疼痛不适等情况,种植体愈合良好。修复后患者咀嚼功能恢复良好,种植体周围软组织健康,患者对短种植体的修复满意。结论：只要严格选择适应症,规范手术操作,短种植体在一定程度上能解决牙槽骨高度不足的问题,避免复杂的外科手术,减少创伤。     

Comparison of survival rate and crestal bone loss of narrow diameter dental implants versus regular dental implants: A systematic review and meta‐analysis

The aim of the present study was to establish survival rates, as well as crestal bone loss (CBL) of narrow diameter implants (NDI), compared to regular diameter implants (RDI). The current review followed the Enhancing the QUAlity and Transparency Of health Research guidelines and Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. We searched main databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register) for articles addressing the focused question up to and including May 2018. Meta‐analyses were conducted for CBL and survival rates. Qualitatively, three clinical studies showed comparable CBL and survival rates between NDI and RDI at follow up. Only one study showed increased CBL around NDI compared to RDI. The overall weighted mean difference (WMD) for CBL (WMD = .06, 95% confidence interval [CI] = ‐.38‐.51, P=.76) and risk difference for survival rate (risk difference = .88, 95% CI = .22‐3.50, P=.85) were not significant between the NDI and RDI groups at follow up. NDI and RDI showed comparable CBL and survival rates. However, the findings of the present study should be interpreted with caution due to significant heterogeneity and the low number of included studies. Further randomized, controlled trials should be performed in order to obtain strong conclusions.     

Effectiveness of glucocorticoids in orthognathic surgery: an overview of systematic reviews

For decades, short-term glucocorticoids have been advocated to reduce postoperative swelling, pain, trismus, and nausea and vomiting in patients experiencing maxillofacial surgeries. The purpose of this systematic overview was to identify and assess the best evidence regarding the efficacy of glucocorticoid administration in patients who undergo orthognathic surgery. Five databases (Medline, Embase, The Cochrane Library, Web of Science, and Epistemonikos) were searched from their inception to October 2020. The risk of bias assessment was performed using the ROBIS tool, and the quality of the evidence reported was rated using the GRADE approach. Six systematic reviews were identified, of which three were included in this overview (n=527). According to the rating of the overall risk of bias, one achieved a low score and two were rated as high. The quality of the evidence reported ranged from very low to moderate. Corticoids may reduce the incidence of moderate or severe postoperative nausea and vomiting in the early postoperative period (0-6 hours) compared to metoclopramide, but the evidence is very uncertain. Some significant therapeutic effects on neurosensory recovery have been reported, but there was inconsistency across the studies. Finally, based on a moderate quality of evidence, it is possible to establish that the administration of glucocorticoids is likely to reduce oedema in the early postoperative period (0-48 hours) in patients who undergo orthognathic surgery, and to have no significant adverse effects. Further quantitative syntheses based on well-designed and standardised clinical studies are suggested to determine direction and strength of the intervention on the other outcomes.     

Lateral augmentation of the sinus floor followed by regular implants versus short implants in the vertically deficient posterior maxilla: a systematic review and timewise meta-analysis of randomized studies

The aim of this study was to perform a timewise meta-analysis of randomized clinical trials (RCTs) comparing the outcomes of short implants (≤6 mm) versus lateral sinus floor augmentation followed by regular implants (≥10 mm) in the deficient posterior maxilla. Eleven RCTs with 1, 3, and 5 years of follow-up were reported in 21 articles. There was no significant difference in the implant loss rate at the patient level after 1 and 3 years between the two groups (risk ratio 0.50, P = 0.17; risk ratio 1.71, P = 0.51). After 5 years, the risk ratio was in favour of regular implants with augmentation and approached significance (3.28, P = 0.06). Excluding the results of two studies on ultrashort implants, the risk ratio for complications was in favour of short implants, but without significance (0.33, P = 0.08). Mean marginal bone loss was significantly lower at 1, 3, and 5 years for the short implants when compared to regular implants with augmentation. The residual osseointegration length of implants was between 3.4 mm and 5.9 mm in the short implants group and between 10.1 mm and 12.5 mm in the regular implants group after 5 years. In conclusion, short implants in the atrophic posterior maxilla demonstrate comparable outcomes to regular implants within the first 5 years. Patients who are fit for surgery should be informed about the risks and benefits of both options.     

Immediate versus delayed positioning of dental implants in guided bone regeneration or onlay graft regenerated areas: a systematic review

The aim of this study was to compare success rates in immediate and delayed dental implant placement following guided bone regeneration or onlay bone block ridge augmentation. A systematic review of all studies on this topic was performed. For inclusion, studies had to involve at least five patients, report specific success criteria, and have a minimum follow-up period of 6 months. Studies reporting only the survival rate of implants were excluded. From 287 studies identified, 79 were screened and 13 were included in the analysis. Six studies provided data on simultaneous (immediate) positioning of implants, five studies on delayed positioning, and two studies provided data on both of these approaches. Success rates for implants placed using a simultaneous approach ranged from 61.5% to 100%; success rates for implants placed using a staged approach ranged from 75% to 98%. Even though the current review revealed that there are not many studies reporting data relevant to the analyzed topic, the data obtained suggest that the delayed positioning of implants should be considered more predictable than the immediate positioning. Studies presenting a control group and adopting standardized success criteria are required, and data from this review must be considered indicative.     

下颌覆盖义齿短微型种植体与标准长度微型种植体效果比较

目的:比较下颌覆盖义齿短微型种植体(mini dental implant,MDI)与标准长度MDI修复牙槽嵴重度萎缩无牙颌患者的效果,为临床应用提供参考.方法:选择进行下颌覆盖义齿短MDI和标准长度MDI修复的无牙颌患者60例,分为短MDI组(30例)和标准MDI组(30例),比较2组基线、术后1周和1年种植体周围组...     

Survival of immediately loaded dental implants in deficient alveolar bone sites augmented with beta-tricalcium phosphate

PURPOSE: Dental implant placement in atrophic alveolar ridges often necessitates grafting procedures, followed by immediate or delayed implant placement. This study assessed the survival of immediately loaded dental implants placed in deficient alveolar bone sites at bone grafting. MATERIALS: From 1999 to May 2002, 1 operator (A.P.) inserted 1065 implants (607 in mandibles, 458 in maxillae) into 338 partially edentulous patients. Most implants were placed into compromised residual ridges or prepared tooth extraction sockets. Implants placed in augmented areas were splinted to implants in nonaugmented sites for stability. In all cases, beta-tricalcium phosphate was mixed with blood from the surgical site to augment the ridge level or fill spaces between the implant and socket wall. When indicated, the same materials were used for sinus floor augmentation. All implants were tapered screws with roughened surfaces, primarily (75%) from 1 manufacturer. One of the authors (Z.O.) prosthetically restored a total of 189 implants that were placed in 35 patients. In this group of patients, complete restorative data were available. All implants were monitored for 12-48 months (mean = 19.2; median = 24). RESULTS: A total of 1039 implants survived, and 26 failed, including 5 in the anterior mandible and 21 in the maxillae. In the restorative group, 186 implants survived, and 3 maxillary implants failed. All implant failures in this study occurred in the augmented sites. CONCLUSION: Within the limitations of this study, immediate loading of splinted implants in augmented sites is a predictable procedure.     

Clinical effectiveness of clear aligner treatment compared to fixed appliance treatment: an overview of systematic reviews

Clinical Oral Investigations - To evaluate the available evidence regarding clinical effectiveness of clear aligner treatment (CAT). A comprehensive literature search was conducted for systematic...     

Surface-conditioned dental implants: an animal study on bone formation

Aim: The aim of this study was to determine whether bone formation around surface-conditioned implants is enhanced compared with non-surface-conditioned sandblasted acid-etched titanium implants.
Materials and Methods: One hundred and forty-four implants were placed in the mandible of 18 minipigs. Before placement, implants were either surface conditioned in a solution containing hydroxide ions (conSF) or assigned to controls. Animals were euthanized after 2, 4 and 8 weeks of submerged healing, the 8-week group receiving polyfluorochrome labelling at week 2, 4, 6 and 8. One jaw quadrant per animal was selected for histological and histomorphometrical evaluation of mineralized bone–implant contact (mBIC), osteoid–implant contact (OIC) and bone volume (BV) analysis.
Results: Polyfluorochrome labelling showed no general differences in bone dynamics. mBIC showed the most pronounced differences after 2 weeks, reaching 65.5% for conSF compared with 48.1% for controls, p =0.270. Differences levelled out after 4 weeks (67.4% control, 65.7% conSF) and 8 weeks (64.0% control, 70.2% conSF). OIC levels were initially comparable, showing a slower decline for conSF after 4 weeks. BV was higher for conSF at all times. No significant differences could be found.
Conclusion: A tendency towards increased mBIC was shown for surface-conditioned implants after short-term healing.     

不可吸收膜联合去蛋白化无机牛骨行垂直性骨增量对种植体早期负重影响的非对照性前瞻性队列研究

目的：使用去蛋白化无机牛骨（Bio-Oss）及钛加强膜（Gore～Tex）在拟种植区先进行垂直性骨增量,对种植体植入后进行早期负重,评估种植体负重1年后的成功率。材料和方法：20名患者的25个位点采用Bio—Oss联合膨胀的聚四氟乙烯钛加强膜进行垂直性引导骨再生手术（GBR）．1年后．取出膜．植入64枚种植体（基线水平）．30d后负重。基线水平及1年后摄标准根尖片。由1名独立的观测者对X线片上组织再生量及种植体周围骨水平进行临床评估。检测指标包括：手术成功率、种植体存留率、并发症情况、垂直骨再生量、种植体周围骨量以及组织学观察。结果：无患者失访．25个部位中23处愈合良好,有2处显示早期膜暴露．再次进行外科手术,2个月后也获得良好愈合。临床检测显示：平均垂直骨丧失5．6mm（s=1．7mm）,行GBR术后,垂直骨量平均增加了5．2mm（s=1.5mm）。来自4名患者的5个组织学样本显示．异体骨及新生骨占骨总量的52．6％．散在的移植物颗粒被层状骨包绕。1年的功能负重后所有的种植体均处于稳定状态．种植体存留率为100％。在1年的随访期中,从X线片观察到种植体周骨丧失与基线水平相比有明显的统计学差异（0、95mm;S=0．21mm;95％可信区间0．85～1．05：P〈0．001）。结论：本前瞻性队列研究显示．通过使用去蛋白化无机牛骨及不可吸收加强钛膜．可获得满意的垂直骨量增加．种植体植入30d后即可负载,种植体功能负重1年后．再生的垂直骨组织显示良好的稳定性。