[Table/Fig-1]:

Reviewed papers purpose and final considerations

Authors	Purpose	Conclusions
Mendonça et al., [1]	To report on a clinical situation involving a patient restored with a mandibular overdenture that presented a fractured implant 2 years after placement.	The probable cause of the implant fracture was due to biomechanical overload caused by parafunctional habits. The implant head was flattened to make it smooth, retapping the internal screw, installing a new abutment (longer), and fabricating part of the overdenture bar.
Al Quran et al., [2]	To report on a case of implant fracture, its possible causes, and how the case was managed.	The combined effect of the heavy occlusal loading and the type of opposing tooth contacts may have resulted in load concentration over the implant-supported fixed partial denture in both centric and excentric occlusion.
Eckert et al., [3]	To determine the incidence of implant fracture in completely edentulous and partially edentulous arches and to determine what factors may predispose an implant to a higher fracture risk.	Implants fracture at similar rates in the maxilla as in the mandible, implant fractures occur more frequently in partially edentulous restorations, all observed fractures occurred with commercially pure 3.75-mm-diameter threaded implants, and prosthetic or abutment screw loosening preceded implant fracture for the majority of the implants.
Gealh et al., [4]	To investigate the literature to identify causative factors that may lead to fracture of dental implants and to discuss available procedures.	The fracture of osseointegrated dental implants is a late complication that, despite presenting low incidence, is highly frustrating. The causes attributed to the fracture of dental implants are multifactorial. The treatment consists of the removal of the fractured fragment, the installation of another implant and the manufacturing of another prosthesis.
Brägger et al., [5]	To compare the frequency of biological and technical complications with fixedpartialdentures (FPDs) on implants, teeth and as mixed tooth-implant supported FPDs over 4 to 5 years of function.	Favourable clinical conditions were found at tooth and implant abutments after 4-5 years of function. Loss of FPD over 4-5 years occurred at a similar rate with mixed, implant or tooth supported reconstructions. Significantly more porcelain fractures were found in FPDs on implants. Impaired general health status was not significantly associated with more biologicalfailures but bruxism as well as extensions were associated with more technicalfailures.
Berglundh et al., [6]	To systematically review the incidence of biological and technicalcomplications in implant therapy reported in prospectivelongitudinalstudies of at least 5 years.	Implant loss was most frequently described (reported in about 100% of studies), while biologicalcomplications were considered in only 40-60% and technicalcomplications in only 60-80% of the studies. This observation indicates that data on the incidence of biological and technicalcomplications may be underestimated and should be interpreted with caution.
GargalloAlbiol et al., [7]	To evaluate 21 fractured implants, with an analysis of patient age and sex, the type, length and diameter of the implant, positioning in the dental arch, the type of prosthetic rehabilitation involved, the number of abutments and pontics, the presence or absence of distal extensions or cantilevers, and loading time to fracture.	Implant fracture was more common in males than in females, and the mean patient age was 56.9 years. Nineteen cases corresponded to implant-supported fixed prostheses. The great majority of fractured implants were located in the molar and premolar regions, and most fractured within 3-4 years after loading. It is important to know and apply the measures required to prevent implant fracture, and to seek the best individualized solution for each case - though complete implant removal is usually the treatment of choice.
Sánchez-Pérez et al., [8]	To describe the management options and discusses the possible causal mechanisms underlying such failures, as well as the factors believed to contribute to implant fracture.	Implant fracture is often preceded by other mechanical problems that can be interpreted as indicators of implant overload. It is important to avoid mechanical problems and excessive bone reabsorption. Attention should focus on the number, diameter and distribution of the implants, as well as on the design of the prosthesis supported by them. When implant fracture occurs, the best management option is to remove the fragment remaining in the maxilla or mandible. The new implant replacing it should be as wide as possible, with due checking and adjustment of the occlusal forces in order to avoid overload.
Jemt & Lekholm [9]	To report on aImplanttreatment in edentulousmaxillae.	Five-year cumulative implant failure rates varied from 7.9% for patients considered to have enough bone to be provided with fixed prostheses immediately after second-stage surgery to 28.8% for those with severely resorbed jaws receiving an overdenture. Failure of implanttreatment correlated significantly with bone quality and ratio of 7-mm implants.
Gotfredsen & Karlsson [10]	To evaluate whether there was a difference between machined and TiO(2)-blasted implants regarding survival rate and marginal bone loss during a 5-year observation period.	Good 5-year results with small ISFPP in the mandible, as well as in the maxilla were showed. No significant differences were found in failure rate and marginal bone loss around implants with a machined rather than a TiO(2)-blasted surface.
Alssadi et al., [11]	To assess the influence of systemic and local bone and intra-oralfactors on the occurrence of early implant failures, i.e. up to the abutmentconnection.	The indication for the use of oral implants should sometimes be reconsidered when alternative prosthetic treatments are available in the presence of possibly interfering systemic or localfactors.
Romeo et al., [12]	A systematic review was carried out to evaluate the success and survival rate of implants supporting cantilever prosthesis, as well as the incidence of technical and biological complications.	ICFDPS can be considered a r eliable treatment: the systematic review assessed that there is no increase in complication rate due to the presence of the cantilever.
Manor et al., [13]	To characterize and compare early and late implant failures.	Late failures were associated with moderate to severe bone loss, a larger number of failed implants per patient, a higher incidence in men, and mostly in posterior areas. Early failures were associated with minimal bone loss, occurred more in women, at a younger age, and in most cases the implants were intended to support single crowns.
Balshi [14]	To analyze fractured implants.	All fractures had associated marginal bone loss. The majority were supporting posterior prostheses. Parafunctional habits were diagnosed in all patients. Most patients presented with loosening or fracture of prosthetic gold screws or abutment screws prior to fracture. This study reports on the treatment of fractured implants accomplished by refacing the fractured titanium and adapting new abutments or replacing the entire implant with subsequent prosthesis refabrication.
Velásquez-Plata et al., [15]	To report on the fracture of a standard endosseous dental implant 11 years after placement.	Scanning electron microscopy revealed striations on the fracture surface, suggesting a fatigue-associated failure.
Piattelli et al., [16]	To present a light and scanningelectronmicroscopic study of fourfracturedimplants.	The scanningelectronmicroscopic study of the fractured surfaces of all fourimplants showed the presence of fatigue striations. Bending overload was probably created by a combination of parafunctional forces, boneresorption, posterior location of the implants, and implant diameter.
Gargallo-Albiol et al., [17]	To evaluate 21 fractured implants and their characteristics.	Implant fracture was more common in males, the mean patient age was 56.9 years, corresponded to implant-supported fixed prostheses, located in the molar and premolar regions, and most fractured within 3-4 years after loading.
DiPede et al., [18]	To evaluate the effect on the failure load of preparing a 0.5-mm chamfer finish line on an implant collar at apical depths.	The mean load required to fracture the abutment/implant assembly decreased significantly after various amounts of implant collar preparation.
Mangano et al., [19]	Evaluation of the peri-implantbone responses in implantsretrieved for fractureaftermore than 20 yearsloading.	Histology and histomorphometry showed that, even after many years of function, all implants presented more than adequate bone to implant contact and they appeared to be very well integrated in the peri-implantbone.
Mc Dermott et al., [20]	To identify the types, frequencies, and riskfactorsassociated with complications following placement of dentalimplants.	The overall frequency of implant complications was 13.9% (10.2% inflammatory, 2.7% prosthetic, 1.0% operative), of which 53% were minor Of the 3 factorsassociated with an increased risk for complications, tobacco use and implant staging may be modified by the clinician to enhance outcome.
Goodacre et al., [21]	To determine the types of complicationsthat have been reported in clinical dental implant studies and to provide data regarding their frequency.	Mechanical complications were screw loosening/fracture, implant ractures, framework, resin base and veneering material fractures, opposing prosthesis fractures, and overdenture mechanical retention problems. Some studies also presented phonetic and esthetic complications.
Flanagan [22]	To report on a case of external and occlusaltrauma to dentalimplants.	A traumatic force damaged the implant prosthetic crown, but not the bone encasing the implant or the integration of the implant.