Author (year), country of origin, funding(Y/N/?)-Conflict of interest(Y/N/?)|
|Research question or objectives||Primary outcome(s)||Number and designs of included studies (number of patients and implants)||Control group||SR/SR and M||Databases searched (search date)||Follow-up||Quality assessment tools||Implant loading (immediate/late)||Type of edentulism (total/partial)||Main findings||Main conclusion|
|Wang et al. (2015) , China and Spain, (Y-N) [Q1; 1,96]||To assess the predictability of oral rehabilitation by four zygomatic implants with no anterior support in regard to implant survival, technical and biologic complications||The survival rate of the zygomatic implants||3 human clinical trials (2 prospective and 1 retrospective) (49 patients, 196 ZIs)||None||SR and M||(from September 2000 to November 2013)||30–363 (mo)||None||Immediate loading||Fully edentulous||
- Zygomatic implant survival rate weighted mean (WM) was 96.7% (range, 95.8 to 99.9%), with a 95% confidence interval (CI) of 92.5 to 98.5%.|
- Limited number of surgical complications and prosthetic complications
|Maxillary rehabilitation by four zygomatic implants with no anterior support is a reliable approach|
|Tuminelli et al. (2017) , USA, (NR-NR) [2.39]||To systematically review the outcome of immediate loaded zygomatic implants||Immediate load survival, complications||38 articles||None||SR||PubMed (from 1990 until June 2016)||At least 12 months follow-up (according to text follow-ups ranged between 1 and 10 (y))||None||Immediate loading||Both totally or partially edentulous maxilla||
- The success of implants and prostheses ranged from 96 to 100%.|
- The complication rates are relatively few, rarely catastrophic, and easily managed
|Immediately loading zygomatic implants for the restoration of the severely atrophic maxilla presents a viable alternative for treatment of the atrophic maxilla and is recommended for the restoration of the severely atrophic maxilla with or without anterior conventional implants|
|Molinero-Mourel et al. (2016) , Spain, (NR-N) [1.07]||To analyze and describe the most frequent surgical complications associated with the use of zygomatic implants||Complications||13 articles (1 SR, 5 pros, 5 retros, 1 pros and retros, 1 cohort) (3240 ZIs)||None||SR||PubMed (up to December 2015)||1–12 (y)||None||All studies were immediate loading||Both totally or partially edentulous maxilla||- Out of the most frequent surgical complications, sinusitis (3.9%) and failure in osseointegration (2.44%) are highlighted||Rehabilitation using zygomatic implants is a consolidated therapeutic option although it does not lack in possible complications; therefore, it should be reserved only to professional clinicians with vast surgical experience|
|Goiato et al. (2014) , Brazil (N-N) [1.52]||To evaluate clinical studies on the follow-up survival of implants inserted in the zygomatic bone for maxillary rehabilitation.||Survival of implants||25 articles (design NR) (748 ZIs)||None||SR||PubMed/MEDLINE, Embase, and Cochrane Library databases (from 2000 to July 2012)||Mean follow-up: 42.2 (mo) (range 0–144)||None||Fifteen studies conducted late loading (prosthesis insertion at 4–6 months after initial implant loading), whereas 10 studies reported immediate loading||Both totally or partially edentulous maxilla||
- These studies reported the insertion of a total of 1541 zygomatic implants and 33 implant failures|
-After a 36-month follow-up, the survival rate was 97.86%
- The survival of osseointegrated implants may also be related to the use of suitable presurgical examinations and the parameters used during the surgical procedures|
- Zygomatic implants appear to be an effective alternative for the treatment of an atrophic maxilla.
|Chrcanovic et al. (2013) , Sweden (NR,N) [1.66]||“What is the survival rate of zygomatic implants (ZIs)?” and “What are the most common complications related to surgery of zygomatic implants?”||Survival rate, complication||42 article, 1145 patients and 2402 ZIs||None||SR||PubMed (Up to March 2012)||Range: 6–120 (mo)||None||Between 42 studies, 12 evaluated the use of ZIs applied with immediate function protocols||Both totally or partially edentulous maxilla||
- 12 evaluated the use of ZIs applied immediate protocol and 3 after maxillary resections for tumor ablations (showed lower success.).|
- Of 2402 ZIs, 56 ZIs were reported as failures
- The CSR over a 12-year period was 96.7%.
- ZI placement needs very experienced surgeons since delicate anatomic structures such as the orbita and brain may be involved|
- Despite the high survival rate observed, there is an impending need for further investigations
|Chrcanovic et al. (2016) , Sweden (NR-N) [1.66]||To assess the survival rate of zygomatic implants (ZIs) and the prevalence of complications based on previously published studies||Complications||Sixty-eight studies were included one randomized clinical trial,16 prospective studies, and 51 retrospective analyses, comprising 4556 ZIs in 2161||Conventional implants||SR||PubMed/Medline, Web of Science, and the Cochrane Oral Health Group Trials Register (up to December 2015)||Range: 1–144 (mo)||None||26 studies immediate loading and studies 34 studies evaluating delayed loading protocols||Both totally or partially edentulous maxilla||
Immediate loading showed a statistically lower ZI failure rate than other studies (P = .003).|
- Studies evaluating ZIs for the rehabilitation of patients after maxillary resections presented lower survival rates.
- Postoperative complications: sinusitis, 2.4% soft tissue infection, 2.0%, paresthesia, 1.0% and oroantral fistulas, 0.4%
- ZIs present a high 12-year CSR, with most failures occurring at the early stages postoperatively.|
- Main complication was sinusitis, which can appear several years after placement
|Aboul-Hosn Centenero et al. (2018) , Spain (Y-N) [1.15]||To compare the survival rates (SRs) of oral rehabilitations performed with 2 zygomatic implants (ZIs) combined with regular implants (RIs) versus 4 ZIs||Survival rates||
6 articles (4 prospective and 2 retrospective case series)|
A total of 130 ZIs and 186 conventional implants were placed in 64 patients.
|4 ZIs (case) versus2 ZIs combined with regular implants RIs (control)||SR and M||
MEDLINE/PubMed, Cochrane Central register of Controlled trials|
Cochrane Oral Health group Trials Register, and EMBASE between 2007, and June 30, 2015
|Range: 12–82 (mo)||The criteria were modified according to the PRISMA 2009 checklist statement ||Immediate loading||Fully edentulous||
- ZIs SR weighted mean was 98.0%, CI [96.7 to 99.8%]. For the control group (2 ZIs + 2 RIs) and the test group (4 ZIs), the implant SR was 98.6% and 97.4%, respectively|
- No statistically significant differences in terms of SRs were obtained between both groups, P = 0.286.
- No statistical differences in 2 groups in terms of survival and failure rates. The reduction on treatment time and morbidity related to regenerative approaches may be its main advantage.|
- The zygoma quad seems to be the treatment of choice for the severely atrophic maxilla.