For the edentulous mandible, the literature supports immediate loading of 4 to 6 implants with a moderately rough surface along with a fixed dental prostheses. There is sufficient evidence that posterior implants can be placed in a tilted inclination where the bone ridge height does not allow for a straight implant to be placed.
Daniel Wismeijer, Wiebe Derksen, Ali Tahmaseb, Nicola Zitzmann. February 2016. For the edentulous maxilla, there is preliminary evidence that supports, in association with strictly defined conditions, immediate loading of 4 to 6 moderately rough surface implants with a fixed prostheses. While alveolar ridge resorption is frequently advanced in the anterior region, in the posterior region the lack of bone volume is often the result of increased pneumatization of the maxillary sinus. This situation requires either short implant lengths or a sinus lift elevation using a crestal or lateral approach. This can be carried out either simultaneously, if 4-6 mm residual bone height is present, or in a staged approach where less than 4 mm alveolar ridge height is available. However, one must take into account that the evidence supporting immediate loading does not apply one to one where shorter implants and/or simultaneous bone augmentations are used. Alternatively, to avoid bone augmentation and to shorten the length of a distal cantilever, posterior implants may be placed in a tilted position along the anterior wall of the maxillary sinus.
Scientific evidence suggests that there is no increased risk of implant loss for posterior tilted implants in the mandible and maxilla, but cleaning access may be limited. This statement is made with the understanding that the treatment is challenging. When bone height is limited, a treatment protocol with at least 2 anterior straight and 2 tilted implants in the premolar region can be considered a valid option as long as the clinician has the appropriate education, experience, and skills. Patient’s requests and complaints, general health, potential limitations and treatment history must be analyzed and the patient must be informed about alternative treatment options.
Literature/References (selected publications)
- Support for the underlying treatment concept; fully edentulous dental arches (maxilla and mandibles), restored by the use of 4 dental implants. Two implants in the interforaminal region in a straight position, the axis of two posterior implants will be placed tilted distally. The correction of the axis of the posterior tilted implants is reached by the use of special angulated abutments. The prosthetic reconstruction is done immediately after the implants are placed (Malo et a, 2012; Malo et al., 2011; Malo et al., 2013; Patzelt et al., 2014; Tallarico er al., 2015)
- Successful osseointegration of Straumann® Roxolid® SLActive® Implants in the edentulous jaw (Akoglu et al., 2011; Al-Nawas et al., 2012; Calvo Guirado et al., 2014; Chiapasco et al., 2012; Cordaro et al., 2013; Karabuda et al., 2011; Quirynen et al., 2014)
- Treatment of the edentulous jaw with 4 to 6 straight positioned Straumann® implants (Calvo Guirado et al., 2014; Kinsel and Liss, 2007)
- Angulation of Straumann® implants (Piano et , 2015; ten Bruggenkate et al., 1991; Wismeijer et al., 2010)
- Immediate function with Straumann® SLA/SLActive® implants (Ganeles et a, 2001; Nicolau et al., 2011; Piano et al., 2015; Stoker and Wismeijer, 2011)
- Successful use of short implants (Slotte et al., 2012; ten Bruggenkate et al., 1998; Cannizzaro et al., 2015)
- Successful mid- and long-term follow-up of edentulous patients with Straumann® implants (Buser et al., 2012; Fischer and Stenberg, 2011; Quirynen et , 2014; van Velzen et al., 2014)
Akoglu B, Ucankale M, Ozkan Y, Kulak-Ozkan Y (2011). Five-year treatment outcomes with three brands of implants supporting mandibular overdentures. Int J Oral Maxillofac Implants 26(1):188-194.
Al-Nawas B, Bragger U, Meijer HJ, Naert I, Persson R, Perucchi A et al. (2012). A Double-Blind Randomized Controlled Trial (RCT) of Titanium-13Zirconium versus Titanium Grade IV Small- Diameter Bone Level Implants in Edentulous Mandibles – Results from a 1-Year Observation Period. Clin Implant Dent Relat Res 14(6):896-904.
Buser D, Janner SF, Wittneben JG, Bragger U, Ramseier CA, Salvi GE (2012). 10-Year Survival and Success Rates of 511 Titanium Implants with a Sandblasted and Acid-Etched Surface: A Retrospective Study in 303 Partially Edentulous Patients. Clin Implant Dent Relat Res 14(6):839-851.
Calvo Guirado JL, Mallaun M, Dard M., Lopez Torres JA (2014). Evaluation of 4 mm implants in mandibular edentulous patients with reduced bone height. Surgical preliminary results. Osseointegration 6(2):43-45.
Chiapasco M, Casentini P, Zaniboni M, Corsi E, Anello T (2012). Titanium-zirconium alloy narrow-diameter implants (Straumann Roxolid®) for the rehabilitation of horizontally deficient edentulous ridges: prospective study on 18 consecutive patients. Clin Oral Implants Res 23(10):1136-1141.
Cordaro L, Torsello F, Mirisola DT, V, Baricevic M (2013). Rehabilitation of an edentulous atrophic maxilla with four unsplinted narrow diameter titanium-zirconium implants supporting an overdenture. Quintessence Int 44(1):37-43.
Fischer K, Stenberg T (2011). Prospective 10-Year Cohort Study Based on a Randomized Controlled Trial (RCT) on Implant-Supported Full-Arch Maxillary Prostheses. Part 1: Sandblasted and Acid-Etched Implants and Mucosal Tissue. Clin Implant Dent Relat Res. 2012 Dec;14(6):808-15.
Ganeles J, Rosenberg MM, Holt RL, Reichman LH (2001). Immediate loading of implants with fixed restorations in the completely edentulous mandible: report of 27 patients from a private practice. Int J Oral Maxillofac Implants 16(3):418-426.
Karabuda ZC, Abdel-Haq J, Arisan V (2011). Stability, marginal bone loss and survival of standard and modified sand-blasted, acid-etched implants in bilateral edentulous spaces: a prospective 15-month evaluation. Clin Oral Implants Res 22(8):840-849.
Kinsel RP, Liss M (2007). Retrospective analysis of 56 edentulous dental arches restored with 344 single-stage implants using an immediate loading fixed provisional protocol: statistical predictors of implant failure. Int J Oral Maxillofac Implants 22(5):823-830.
Malo P, de Araujo NM, Lopes A, Francischone C, Rigolizzo M (2012). “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 14 Suppl 1:e139-e150.
Malo P, de Araujo NM, Lopes A, Moss SM, Molina GJ (2011). 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 142(3):310-320.
Malo P, Nobre M, Lopes A (2013). Immediate loading of ‘All-on-4’ maxillary prostheses using trans-sinus tilted implants without sinus bone grafting: a retrospective study reporting the 3-year outcome. Eur J Oral Implantol 6(3):273-283.
Nicolau P, Korostoff J, Ganeles J, Jackowski J, Krafft T, Neves M et al. (2011). Immediate and Early Loading of Chemically Modified Implants in Posterior Jaws: 3-Year Results from a Prospective Randomized Multicenter Study. Clin Implant Dent Relat Res. 2013 Aug;15(4):600-12.
Patzelt SB, Bahat O, Reynolds MA, Strub JR (2014). The all-on-four treatment concept: a systematic review. Clin Implant Dent Relat Res 16(6):836-855.
Piano S, Romeo E, Sbricoli L, Pisoni G, Cea N, Lops D (2015). Simplified procedure for the immediate loading of a complete fixed prosthesis supported by four implants in the maxillary jaw: a 2-year prospective study. Clin Oral Implants Res. doi: 10.1111/clr.12580. [Epub ahead of print]
Quirynen M, Al-Nawas B, Meijer HJ, Razavi A, Reichert TE, Schimmel M et al. (2014). Small- diameter titanium Grade IV and titanium-zirconium implants in edentulous mandibles: three-year results from a double-blind, randomized controlled trial. Clin Oral Implants Res. 2015 Jul;26(7):831-40.
Slotte C, Gronningsaeter A, Halmoy AM, Ohrnell LO, Stroh G, Isaksson S et al. (2012). Four- millimeter implants supporting fixed partial dental prostheses in the severely resorbed posterior mandible: two-year results. Clin Implant Dent Relat Res 14 Suppl 1:e46-e58.
Stoker GT, Wismeijer D (2011). Immediate loading of two implants with a mandibular implant- retained overdenture: a new treatment protocol. Clin Implant Dent Relat Res 13(4):255-261.
ten Bruggenkate CM, Asikainen P, Foitzik C, Krekeler G, Sutter F (1998). Short (6-mm) nonsubmerged dental implants: results of a Multicenter clinical trial of 1 to 7 years. Int J Oral Maxillofac Implants 13(6):791-798.
ten Bruggenkate CM, Oosterbeek HS, Krekeler G, Asikainen PJ (1991). The placement of angled implants in the edentulous maxillae for the use of overdentures. J Prosthet Dent 66(6):807-809.
van Velzen FJ, Ofec R, Schulten EA, ten Bruggenkate CM (2014). 10-year survival rate and the incidence of peri-implant disease of 374 titanium dental implants with a SLA surface: a prospective cohort study in 177 fully and partially edentulous patients. Clin Oral Implants Res.
Wismeijer D, Casentini P, Gallucci GO, Chiapasco M (2010). ITI Treatment Guide; Loading Protocols in Implant Dentistry; Edentulous Patients. Berlin: Quintessence Publishing Co, Ltd.
Zitzmann NU, Schärer P. Sinus elevation procedures in the resorbed posterior maxilla. Comparison of the crestal and the lateral approach. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1998;85:8-17.
Tallarico M, Meloni SM, Canullo L, Caneva M, Polizzi G. Five-Year Results of a Randomized Controlled Trial Comparing Patients Rehabilitated with Immediately Loaded Maxillary Cross- Arch Fixed Dental Prosthesis Supported by Four or Six Implants Placed Using Guided Surgery. Clin Implant Dent Relat Res 2015 Oct 7. doi: 10.1111/cid.12380.
Cannizzaro G, Felice P, Buti J, Leone M, Ferri V, Esposito M. Immediate loading of fixed cross- arch prostheses supported by flapless-placed supershort or long implants: 1-year results from a randomised controlled trial. Eur J Oral Implantol 2015 Spring;8(1):27-36.