|Year : 2021 | Volume
| Issue : 1 | Page : 3-10
Survival rates of axial and tilted implants in the rehabilitation of edentulous jaws using the All-on-four™ concept: A systematic review
Sneha Harishchandra Gaonkar, Meena Ajay Aras, Vidya Chitre, Kennedy Mascarenhas, Bhavya Amin, Praveen Rajagopal
Department of Prosthodontics, Goa Dental College and Hospital, Bambolim, Goa, India
|Date of Submission||10-Mar-2020|
|Date of Decision||15-May-2020|
|Date of Acceptance||20-Sep-2020|
|Date of Web Publication||29-Jan-2021|
Dr. Sneha Harishchandra Gaonkar
Department of Prosthodontics, Goa Dental College and Hospital, Bambolim, Goa
Source of Support: None, Conflict of Interest: None
Aim: The aim of this review was to evaluate the survival rate of axial and tilted implants in rehabilitation of edentulous jaws using all on four concept.
Setting and Design: Systematic Review.
Materials and Methods: A literature review was performed in MEDLINE, PubMed Central (PMC), Google scholar, Embase, Cochrane Central Register of Controlled Trials. Hand searches were conducted of the bibliographic of related journals and systematic reviews. A total of 380 articles were obtained from the intial screening process. Of these articles, 25 articles fulfilled the inclusion criteria. The authors performed evaluation of articles independently as well as data extraction and quality assessment.
Statistical Analysis Used: Qualitative analysis.
Results: The major prosthetic complication was the fracture of the acrylic prosthesis. The mean cumulative survival rate of implants (72-132 months) were 94% to 98%. The prosthesis survival rate (12 months) was between 99% to 100%. The averaged bone loss was 1.3 ±0.4 mm (12-60 months). No Significant difference was found between survival rates of axial and tilted implants nor between maxilla and mandible.
Conclusion: All on four concept can be employed successfully in the edentulous patients with resorbed ridges while improving their quality of life and reducing morbidity. However,randomized clinical trials with large sampling size and long term follow up should be incorporated.
Keywords: All-on-four™, axial implants, mandible, maxilla, tilted implants
|How to cite this article:|
Gaonkar SH, Aras MA, Chitre V, Mascarenhas K, Amin B, Rajagopal P. Survival rates of axial and tilted implants in the rehabilitation of edentulous jaws using the All-on-four™ concept: A systematic review. J Indian Prosthodont Soc 2021;21:3-10
|How to cite this URL:|
Gaonkar SH, Aras MA, Chitre V, Mascarenhas K, Amin B, Rajagopal P. Survival rates of axial and tilted implants in the rehabilitation of edentulous jaws using the All-on-four™ concept: A systematic review. J Indian Prosthodont Soc [serial online] 2021 [cited 2021 Oct 23];21:3-10. Available from: https://www.j-ips.org/text.asp?2021/21/1/3/308184
| Introduction|| |
The occurrence of edentulism among elderly patients has been shown to have a negative impact on their quality of life. It is a debilitating and irreversible condition leading to functional impairment and physical, psychological, and social disability. The treatment options available for these patients are complete dentures and removable or fixed implant-supported prosthesis.
Prosthetic rehabilitation of completely edentulous patients with implants is a reliable mode of treatment, but its success depends on the availability of good quality and quantity of bone. Patients with severe resorption of the alveolar bone require prior surgical intervention such as bone augmentation and sinus lift procedures for a successful outcome.,, These techniques increase patient morbidity and treatment fees and can have associated complications. To overcome these disadvantages, the concept of “All-on-four™” was introduced by Paulo Malo in 2003. This concept demonstrates placing two anterior implants in an axial position and two posterior implants with a tilt of up to 45° to support a full-arch fixed restoration. Bone grafting is avoided by tilting the posterior implants, thus utilizing the available bone. Advantages of tilting implants are that it eliminates the need for invasive procedures such as sinus floor augmentation and bone augmentation, preserves anatomical structures such as sinus floor in the maxilla and inferior alveolar nerve in the mandible, allows for placement of longer implants with good cortical anchorage, and increases interimplant space, thus reducing cantilever length in jaws and helping in better force distribution, thus reducing load on the implants.,,,,,,,,, Disadvantages of tilting implants include the technical sensitivity of the procedure and the need of computer-guided surgical stent for implant to be placed in an optimal position.,,, The purpose of this review article is to evaluate the survival rate (SR) of axial and tilted implants to rehabilitate completely edentulous maxilla and mandible.
Objectives of the study
The objectives of the study are to evaluate the survival rates of tilted and axial implants placed in human either in the maxilla or mandible using All-on-four treatment concept, bone level changes around these implants, and survival rates of fixed dental prostheses on these implants.
| Materials and Methods|| |
Search method and identification of studies
A literature review was performed in MEDLINE, PubMed Central, Google Scholar, Embase, and Cochrane Central Register of Controlled Trials.
Keywords such as “All on 4,” “All-on-four,” “tilted implant,” “angled implant,” “upright implant,” “axial implant,” “four implants,” “edentulous patient,” “edentulous mandible,” and “edentulous maxilla” were used alone or in combination.
Types of studies
Clinical trials reporting on the survival rates of axial and tilted implants, survival rates of full-arch fixed prosthesis, and changes in the bone levels around implants with a minimum follow-up period of 1 year were considered.
The following articles were excluded:
- Systematic reviews
- Case reports
- Biomechanical trials
- Finite-element analyses and
- Trials including more than four implants, zygomatic implants, and pterygoid implants.
Types of participants
Studies involving only human subjects were included.
Types of outcome measurements and data collection
For each study, the following data were collected: name of the authors, type of study design, number of jaws investigated, total number of implants, number of implants in the maxilla and mandible, implant survival rates, prosthesis survival rates, and marginal bone loss.
| Results|| |
The electronic search yielded a total of 380 articles. The search results were combined, and articles including the words “case report,” “literature review,” and “finite element analysis” in the title were excluded and seventy papers were considered. Of these, 45 trials were excluded after reading full texts for the initial screening process [Table 1],[Table 2],[Table 3], and 25 articles fulfilled the inclusion criteria. Fourteen studies reported were prospective studies and 11 studies reported were retrospective studies [Table 2] and [Table 4].
Outcomes of the studies
During the follow-up period, it was seen that the majority of implant failures were seen within 12 months of surgical placement. The reasons for failure were reported to be lack of osseointegration and infections.
There was no significant difference in the outcome of tilted versus axial implants in the maxilla and the mandible. In addition, no significant difference was found between tilted and axial implants in their respective jaws [Table 4].
The most common prosthesis-related problem reported was fracture of the provisional acrylic prosthesis. Other problems reported were wear patterns in the opposing dentition and prosthetic screw loosening in the cases of bruxers.
In all the studies, bone-level changes were evaluated based on the measurements of the distance between the implant neck and the first sign of bone-to-implant contact radiographically. Marginal bone loss level was reported separately for both tilted and axial implants in 15 trials. It was found that there was no significant difference for bone loss values for both tilted and axial implants and also for maxillary and mandibular implants.
| Discussion|| |
The “All-on-4” concept to support fixed full-arch prostheses has been gaining popularity because it offers a predictable treatment option to rehabilitate edentulous patients while eliminating regenerative procedures and complications inherent to these procedures. The patient is benefitted by the provision of a fixed full-arch prosthesis on the day of the surgery, a shorter treatment time due to elimination of time-consuming bone-grafting procedures, and the low cost of the treatment compared to conventional implant treatment modalities.
Out of 380 publications, only 25 papers provided substantial information about the all-on-4 concept to evaluate the SR of axial and tilted implants, fixed prostheses, and marginal bone-level changes.
Most of the studies reported were of retrospective or prospective. None of the studies were designed as a randomized controlled trial (RCT).
Malo et al. reported the results of implant SR up to 132 months (cumulative survival rate [CSR] 94.8%) and a SR up to 72 months (CSR 98%). In this review, no statistically significant difference was observed in the SR of axial and tilted implants. Due to the absence of RCT, the efficacy of immediate rehabilitation supported by axial and tilted implants cannot be evaluated definitely, However, based on the included studies in the review, it is seen that prognosis of the implant is excellent.,,,,,,,,,,,,,,,,,,,,,,,
Regarding marginal bone level changes, no significant difference was found between axial and tilted implants. Most of the included studies reported limited marginal bone loss on an average of <1.5 mm for axial and tilted implants for a follow-up period of 12 months.,,,,,,,,,,,,,,,,,,, The studies by Maló et al. and Krennmair et al. reported limited marginal bone loss of 1.74 mm and 1.17 mm for axial implants and 1.76 mm and 1.24 mm for tilted implants, respectively, for a follow-up period of 5 years. Only one study defined success criterion for bone loss as no more than 1.5 mm by the end of the 1st year of functional loading or 0.2 mm/year in the subsequent years.
In addition, when comparing either the maxilla and mandible, no statistically significant differences were found in the SR of implants.
The above-mentioned studies suggest that the placement of implant in the jaws (maxilla/mandible) or angulation of implant using the “All-on-4” concept does not affect the bone levels.
The prostheses were incorporated within 48 h after the surgery in all the included studies. The most common complication reported was the fracture of the acrylic prosthesis. This was mainly seen in bruxers due to progressive wear of the resin material. Therefore, it is recommended to reinforce definitive prostheses with cast metal frameworks.
This review is based only on prospective and retrospective studies which gave limited information on the prognosis of the All-on-4 technique for a short term. To determine the efficacy of this, RCTs with large sample size and long-term follow-up should be incorporated.
| Conclusion|| |
The All-on-four treatment concept seems to be an approach for edentulous jaws according to the common demand of a cost-effective treatment concept, decreased treatment times, and higher patient quality of life compared to extended surgical approaches. The results obtained from the studies indicate an implant SR of 98% to 94.8% for a follow-up period of 72–132 months. The marginal bone loss of 1.5 mm to 1.7 mm for axial and tilted implants was reported for a follow-up period of 12–60 months. The prosthesis SR was reported between 99% and 100% for the follow-up period of 12 months. Proper patient selection, thorough evaluation of patients, and good surgical skills of the operator are important to establish predictable treatment outcomes.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Agliardi E, Clerico M, Ciancio P, Massironi D. Immediate loading of full-arch fixed prostheses supported by axial and tilted implants for the treatment of edentulous atrophic mandibles. Quintessence Int 2010;41:285-93.
Agliardi E, Panigatti S, Clerico M, Villa C, Malo P. Immediate rehabilitation of the edentulous jaws with full fixed prostheses supported by four implants: Interim results of a single cohort prospective study. Clin Oral Implants Res 2010;21:459-65.
Babbush CA, Kutsko GT, Brokloff J. The All-on-four immediate function treatment concept with NobelActive implants: A retrospective study. J Oral Implantol 2011;37:431-45.
Butura CC, Galindo DF, Jensen OT. Mandibular All-on-four therapy using angled implants: A three-year clinical study of 857 implants in 219 jaws. Oral Maxillofac Surg Clin North Am 2011;23:289-300, vi.
Capelli M, Zuffetti F, Del Fabbro M, Testori T. Immediate rehabilitation of the completely edentulous jaw with fixed prostheses supported by either upright or tilted implants: A multicenter clinical study. Int J Oral Maxillofac Implants 2007;22:639-44.
Crespi R, Vinci R, Capparé P, Romanos GE, Gherlone E. A clinical study of edentulous patients rehabilitated according to the “All-on-four” immediate function protocol. Int J Oral Maxillofac Implants 2012;27:428-34.
Francetti L, Agliardi E, Testori T, Romeo D, Taschieri S, Del Fabbro M. Immediate rehabilitation of the mandible with fixed full prosthesis supported by axial and tilted implants: Interim results of a single cohort prospective study. Clin Implant Dent Relat Res 2008;10:255-63.
Francetti L, Romeo D, Corbella S, Taschieri S, Del Fabbro M. Bone level changes around axial and tilted implants in full-arch fixed immediate restorations. Interim results of a prospective study. Clin Implant Dent Relat Res 2012;14:646-54.
Hinze M, Thalmair T, Bolz W, Wachtel H. Immediate loading of fixed provisional prostheses using four implants for the rehabilitation of the edentulous arch: A prospective clinical study. Int J Oral Maxillofac Implants 2010;25:1011-8.
Landázuri-Del Barrio RA, Cosyn J, De Paula WN, De Bruyn H, Marcantonio E Jr. A prospective study on implants installed with flapless-guided surgery using the All-on-four concept in the mandible. Clin Oral Implants Res 2013;24:428-33.
Maló P, de Araujo Nobre M, Lopes A. The use of computer-guided flapless implant surgery and four implants placed in immediate function to support a fixed denture: Preliminary results after a mean follow-up period of thirteen months. J Prosthet Dent 2007;97:S26-34.
Weinstein R, Agliardi E, Fabbro MD, Romeo D, Francetti L. Immediate rehabilitation of the extremely atrophic mandible with fixed full-prosthesis supported by four implants. Clin Implant Dent Relat Res 2012;14:434-41.
Maló P, de Araújo Nobre M, Lopes A, Francischone C, Rigolizzo M. “All-on-4” immediate-function concept for completely edentulous maxillae: A clinical report on the medium (3 years) and long-term (5 years) outcomes. Clin Implant Dent Relat Res 2012;14 Suppl 1:e139-50.
Galindo DF, Butura CC. Immediately loaded mandibular fixed implant prostheses using the All-on-four protocol: A report of 183 consecutively treated patients with 1 year of function in definitive prostheses. Int J Oral Maxillofac Implants 2012;27:628-33.
Maló P, Rangert B, Nobre M. All on 4 Immediate function concept with Branemark system Implants for completely edentulous edentulous maxilla: A 1 year retrospective clinical study. Clin Implant Dent Relat Res 2005;7 Suppl 1:S88-94.
Balshi TJ, Wolfinger GJ, Slauch RW, Balshi SF. A retrospective analysis of 800 Branemark system implants following the All-on-FourTM
Protocol. J Prosthodont 2014;23:83-8.
Di P, Lin Y, Li JH, Luo J, Qiu LX, Chen B, et al
. The All-on-Four implant therapy protocol in the management of edentulous Chinese patients. Int J Prosthodont 2013;26:509-16.
Malo P, de Araújo Nobre M, Lopes A, Moss SM, Molina GJ. A longitudinal study of the survival of All-on-4 implants in the mandible with up to 10 years of follow-up. J Am Dent Assoc 2011;142:310-20.
Agliardi EL, Pozzi A, Stappert CF, Benzi R, Romeo D, Gherlone E. Immediate fixed rehabilitation of the edentulous maxilla: A prospective clinical and radiological study after 3 years of loading. Clin Implant Dent Relat Res 2014;16:292-302.
Cavalli N, Barbaro B, Spasari D, Azzola F, Ciatti A, Francetti L. Tilted implants for full-arch rehabilitations in completely edentulous maxilla: A retrospective study. Int J Dent 2012;2012:180379.
Arvidson K, Bystedt H, Frykholm A, von Konow L, Lothigius E. A 3-year clinical study of Astra dental implants in the treatment of edentulous mandibles. Int J Oral Maxillofac Implants 1992;7:321-9.
Lopes A, Maló P, de Araújo Nobre M, Sanchez-Fernández E. The NobelGuide® All-on-4® treatment concept for rehabilitation of edentulous jaws: A prospective report on medium- and long-term outcomes. Clin Implant Dent Relat Res 2015;17 Suppl 2:e406-16.
Browaeys H, Dierens M, Ruyffelaert C, Matthijs C, De Bruyn H, Vandeweghe S. Ongoing crestal bone loss around implants subjected to computer-guided flapless surgery and immediate loading using the All-on-4® concept. Clin Implant Dent Relat Res 2015;17:831-43.
Arvidson K, Esselin O, Felle-Persson E, Jonsson G, Smedberg JI, Soderstrom U. Early loading of mandibular full-arch bridges screw retained after 1 week to four to five Monotype implants: 3-year results from a prospective multicentre study. Clin Oral Implants Res 2008;19:693-703.
Astrand P, Almfeldt I, Brunell G, Hamp SE, Hellem S, Karlsson U. Non-submerged implants in the treatment of the edentulous lower jar. A 2-year longitudinal study. Clin Oral Implants Res 1996;7:337-44.
Maló P, de Araújo Nobre M, Lopes A, Ferro A, Gravito I. All-on-4® treatment concept for the rehabilitation of the completely edentulous mandible: A 7-year clinical and 5-year radiographic retrospective case series with risk assessment for implant failure and marginal bone level. Clin Implant Dent Relat Res 2015;17 Suppl 2:e531-41.
Krennmair G, Seemann R, Weinländer M, Krennmair S, Piehslinger E. Clinical outcome and peri-implant findings of four-implant-supported distal cantilevered fixed mandibular prostheses: Five-year results. Int J Oral Maxillofac Implants 2013;28:831-40.
Agliardi EL, Francetti L, Romeo D, Del Fabbro M. Immediate rehabilitation of the edentulous maxilla: Preliminary results of a single-cohort prospective study. Int J Oral Maxillofac Implants 2009;24:887-95.
Ata-Ali J, Peñarrocha-Oltra D, Candel-Marti E, Peñarrocha-Diago M. Oral rehabilitation with tilted dental implants: A metaanalysis. Med Oral Patol Oral Cir Bucal 2012;17:e582-7.
Bedrossian E. Rescue implant concept: The expanded use of the zygoma implant in the graftless solutions. Oral Maxillofac Surg Clin North Am 2011;23:257-76, vi.
Bedrossian E. Rescue implant concept: The expanded use of the zygoma implant in the graftless solutions. Dent Clin North Am 2011;55:745-77.
Butura CC, Galindo DF, Cottam J, Adams M, Jensen O. Hourglass mandibular anatomic variant incidence and treatment considerations for All-on-four implant therapy: Report of 10 cases. J Oral Maxillofac Surg 2011;69:2135-143.
Cannizzaro G, Felice P, Soardi E, Ferri V, Leone M, Esposito M. Immediate loading of 2 (all-on-2) versus 4 (allon-4) implants placed with a flapless technique supporting mandibular cross-arch fixed prostheses: Preliminary results from a pilot randomised controlled trial. Eur J Oral Implantol 2011;4:205-17.
Degidi M, Nardi D, Piattelli A. Immediate loading of the edentulous maxilla with a definitive restoration supported by an intraorally welded titanium bar and tilted implants. Int J Oral Maxillofac Implants 2010;25:1175-82.
Del Fabbro M, Bellini CM, Romeo D, Francetti L. Tilted implants for the rehabilitation of edentulous jaws: A systematic review. Clin Implant Dent Relat Res 2012;14:612-21.
Di P, Lin Y, Li JH, Qiu LX, Chen B, Cui HY. Clinical study of “All-on-4” implant immediate function in edentulous patients. Zhonghua Kou Qiang Yi Xue Za Zhi 2010;45:357-62.
Ekelund JA, Lindquist LW, Carlsson GE, Jemt T. Implant treatment in the edentulous mandible: A prospective study on Brånemark system implants over more than 20 years. Int J Prosthodont 2003;16:602-8.
Eccellente T, Piombino M, Piattelli A, D'Alimonte E, Perrotti V, Iezzi G. Immediate loading of dental implants in the edentulous maxilla. Quintessence Int 2011;42:281-9.
Friberg B, Jemt T. Rehabilitation of edentulous mandibles by means of four TiUnite implants after one-stage surgery: A 1-year retrospective study of 75 patients. Clin Implant Dent Relat Res 2010;12 Suppl 1:e56-62.
Ferreira EJ, Kuabara MR, Gulinelli JL. “All-on-four” concept and immediate loading for simultaneous rehabilitation of the atrophic maxilla and mandible with conventional and zygomatic implants. Br J Oral Maxillofac Surg 2010;48:218-20.
Graves S, Mahler BA, Javid B, Armellini D, Jensen OT. Maxillary All-on-four therapy using angled implants: A 16-month clinical study of 1110 implants in 276 jaws. Dent Clin North Am 2011;55:779-94.
Graves S, Mahler BA, Javid B, Armellini D, Jensen OT. Maxillary All-on-four therapy using angled implants: A 16-month clinical study of 1110 implants in 276 jaws. Oral Maxillofac Surg Clin North Am 2011;23:277-87.
Heschl A, Payer M, Platzer S, Wegscheider W, Pertl C, Lorenzoni M. Immediate rehabilitation of the edentulous mandible with screw type implants: Results after up to 10 years of clinical function. Clin Oral Implants Res 2012;23:1217-23.
Jensen O, Cottam J, Adams M, Adams S. Buccal to lingual transalveolar implant placement for All-on-four immediate function in posterior mandible: Report of 10 cases. J Oral Maxillofac Surg 2011;69:1919-22.
Jensen OT, Adams MW. All-on-4 treatment of highly atrophic mandible with mandibular V-4: Report of 2 cases. J Oral Maxillofac Surg 2009;67:1503-9.
Jensen OT, Adams MW, Cottam JR, Parel SM, Phillips WR 3rd
. The All-on-4 shelf: Maxilla. J Oral Maxillofac Surg 2010;68:2520-7.
Jensen OT, Adams MW, Cottam JR, Parel SM, Phillips WR 3rd
. The all on 4 shelf: Mandible. J Oral Maxillofac Surg 2011;69:175-81.
Jensen OT, Cottam J, Ringeman J, Adams M. Trans-sinus dental implants, bone morphogenetic protein 2, and immediate function for all-on-4 treatment of severe maxillary atrophy. J Oral Maxillofac Surg 2012;70:141-8.
Krekmanov L, Kahn M, Rangert B, Lindström H. Tilting of posterior mandibular and maxillary implants for improved prosthesis support. Int J Oral Maxillofac Implants 2000;15:405-14.
Khatami AH, Smith CR. “All-on-Four” immediate function concept and clinical report of treatment of an edentulous mandible with a fixed complete denture and milled titanium framework. J Prosthodont 2008;17:47-51.
Li W, Chow J, Hui E, Lee PK, Chow R. Retrospective study on immediate functional loading of edentulous maxillas and mandibles with 690 implants, up to 71 months of follow-up. J Oral Maxillofac Surg 2009;67:2653-62.
Menini M, Signori A, Tealdo T, Bevilacqua M, Pera F, Ravera G, et al
. Tilted implants in the immediate loading rehabilitation of the maxilla: A systematic review. J Dent Res 2012;91:821-7.
Orentlicher G, Abboud M. Computed tomography-guided surgery and all on four. J Oral Maxillofac Surg 2011;69:2947.
Oyama K, Kan JY, Kleinman AS, Runcharassaeng K, Lozada JL, Goodacre CJ. Misfit of implant fixed complete denture following computer-guided surgery. Int J Oral Maxillofac Implants 2009;24:124-30.
Penarrocha M, Carrillo C, Boronat A. Maximum use of the anterior maxillary buttress in severe maxillary atrophy with tilted, palatally positioned implants: A preliminary study. Int J Oral Maxillofac Implants 2010;25:813-20.
Peñarrocha M, Viña JA, Carrillo C, Peñarrocha D, Peñarrocha M. Rehabilitation of reabsorbed maxillae with implants in buttresses in patients with combination syndrome. J Oral Maxillofac Surg 2012;70:e322-30.
Pomares C. A retrospective study of edentulous patients rehabilitated according to the “All-on-four” or the “all-on-six” immediate function concept using flapless computer-guided implant surgery. Eur J Oral Implantol 2010;3:155-63.
Penarrocha-Oltra D, Candel-Marti E, Ata-Ali J, Penarrocha M. Rehabilitation of the atrophic maxilla with tilted implants: Review of the literature. J Oral Implantol 2013;39:625-32.
Pomares C. A retrospective clinical study of edentulous patients rehabilitated according to the “All-on-four” or the “all-on-six” immediate function concept. Eur J Oral Implantol 2009;2:55-60.
Parel SM, Phillips WR. A risk assessment treatment planning protocol for the four implant immediately loaded maxilla: Preliminary findings. J Prosthet Dent 2011;106:359-66.
Osen A, Gynther G. Implant treatment without bone grafting in edentulous severely resorbed maxillas: A longterm follow-up study. J Oral Maxillofac Surg 2007;65:1010-16.
Romanos GE, May S, May D. Treatment concept of the edentulous mandible with prefabricated telescopic abutments and immediate functional loading. Int J Oral Maxillofac Implants 2011;26:593-7.
Wu YQ, Huang W, Zhang ZY, Wang XD, Wang F, Wang S. Tilted implants treatment without maxillary sinus grafting in severely resorbed posterior maxilla. Shanghai Kou Qiang Yi Xue 2011;20:506-11.
Christopher CK. Implant rehabilitation in the edentulous jaw: The “All-On-4” immediate function concept. Australasian Dent Practice 2012;138-48.
Babbush CA, Kanawati A, Brokloff J. A new approach to the All-on-Four treatment concept using narrow platform NobelActive implants. J Oral Implantol 2013;39:314-25.
Maló P, Araújo Nobre MD, Lopes A, Rodrigues R. Double full-arch versus single full-arch, four implant-supported rehabilitations: A retrospective, 5-year cohort study. J Prosthodont 2015;24:263-70.
Molina IC, Molina GC, Teixeira KN, Ribas de Andrade PC, Bianchini MA. Atrophic maxilla rehabilitation with use of All-On Four tilted implants. Revista Odontologica Mexicana 2014;18:249-54.
Niedermaier R, Stelzle F, Riemann M, Bolz W, Schuh P, Wachtel H. Implant-supported immediately loaded fixed full-arch dentures: Evaluation of implant survival rates in a case cohort of up to 7 years. Clin Implant Dent Relat Res 2017;19:4-19.
Sannino G, Barlattani A. Straight versus angulated abutments on tilted implants in immediate fixed rehabilitation of the edentulous mandible: A 3-year retrospective comparative study. Int J Prosthodont 2016;29:219-26.
Maló P, Rangert B, Nobre M. “All-on-Four” immediate-function concept with Brånemark System implants for completely edentulous mandibles: A retrospective clinical study. Clin Implant Dent Relat Res 2003;5 Suppl 1:2-9.
[Table 1], [Table 2], [Table 3], [Table 4]