Sinus Floor Elevation Procedures

Hideaki Katsuyama, Simon Storgaard Jensen, Stephen Chen, Daniel Buser, Daniel Wismeijer, Stephen Chen, Daniel Buser, Daniel Wismeijer

• Editorial: Quintessence Publishing
• Año: 2019
• ISBN:
  9783868674965
• Edición: 1
• Categoría: Medicina
• Categoría: Odontotecnica

The fifth volume of the ITI Treatment Guide series presents the materials and techniques associated with sinus augmentation procedures.The volume opens with a review of the current literature and the relevant ITI Consensus Statements derived from the ITI Consensus Conference held in Stuttgart, Germany, in 2008. This is followed by a discussion of the preoperative assessment of the posterior maxilla, including a detailed description of the anatomy and radiologic examination.Different treatment options are then presented, along with guidelines for choosing the appropriate technique based on thorough risk evaluation and the relative complexity of each option. Various procedures are demonstrated with comprehensive patient case studies, and detailed illustrations serve to clarify potential ambiguities in protocol and technique. The text is completed with a section on intraoperative and postoperative complications to avert the most common pitfalls in clinical practice.

1	Introduction
	H. Katsuyama, S. S. Jensen

Continuous advances in the field of implant dentistry have provided clinicians with various treatment options to facilitate the placement of dental implants in patients with vertical bone deficits in the posterior maxilla. Today, one of the most common ways to compensate for inadequate vertical bone height is to elevate the sinus floor. Often employed in combination with bone grafts and bone substitutes, sinus floor elevation procedures are of moderate to high complexity, entailing a significant risk of complications.

In August of 2008, the ITI held the 4th ITI Consensus Conference to discuss a number of current issues in implant dentistry. One focus was on bone augmentation procedures in localized defects and on the clinical efficacy of the different protocols employed with the many grafting materials and techniques available today. The results of this conference were published in a supplement to the International Journal of Oral & Maxillofacial Implants in 2009.

The present fifth volume in the ITI Treatment Guide series summarizes the findings and consensus statements of the 4th ITI Consensus Conference and provides an up-to-date overview of the literature on sinus floor elevation published in the past four years. Reinforced by this scientific evidence, emphasis is placed on clinical recommendations and guidelines for evaluating possible patients for sinus floor elevation and for choosing the appropriate treatment approach and augmentation protocol. All clinical procedures are illustrated and supported by detailed case reports.

As with the preceding four volumes of the ITI Treatment Guide, the authors hope that this fifth volume will prove a valuable resource and reference for clinicians placing implants in patients requiring sinus floor elevation to minimize the risk of complications and to ensure predictable and stable long-term results.

2	Proceedings of the 4th ITI Consensus Conference and Literature Review: Sinus Floor Elevation Procedures

The International Team for Implantology (ITI) is an independent academic organization that brings together professionals from the various fields in implant dentistry and related tissue regeneration. The ITI regularly publishes treatment guidelines based on evidence-based clinical studies supported by long-term clinical results. The ITI Treatment Guides have proven to be an invaluable resource for the clinician active in the field of implant dentistry.

The ITI regularly organizes Consensus Conferences to review the current literature on oral implantology and to evaluate the scientific evidence supporting a wide range of clinical procedures, techniques, and biomaterials. The proceedings are published in peer-reviewed journals. The 4th ITI Consensus Conference was held in Stuttgart, Germany in August 2008. For this conference, the ITI Education Committee focused on four topics:

•Risk factors for implant therapy

•Emerging techniques and technologies in implant dentistry

•Implant loading protocols,

•Surgical techniques in implant dentistry

(Proceedings of the 4th ITI Consensus Conference, International Journal of Oral and Maxillofacial Implants 2009. Vol. 24, Supplement.)

A working group was elected for the exploration of each topic. Working Group 4, under the leadership of Stephen Chen, reviewed the literature on surgical techniques. Sinus floor elevation procedures were one of the topics in focus of this group.

The participants of Working Group 4 were:

Maurício Araújo

Jay Beagle

Daniel Buser

Paolo Casentini

Matteo Chiapasco

Ivan Darby

Javier Fábrega

Paul Fugazzotto

Timothy W. Head

Alessandro Lourenço Januário

Simon Storgård Jensen

Lars-Åke Johansson

John D. Jones

Dehua Li

Thomas Oates

Bjarni E. Pjetursson

Waldemar Daudt Polido

Paul Rousseau

Anthony Sclar

Hendrik Terheyden

Alex Yi-Min Tsai

Gerhard Wahl

Dieter Weingart

Gerrit Wyma

Alvin B. K. Yeo

The following section presents the consensus statements and recommended clinical procedures for sinus augmentation.

2.1	Consensus Statements

Group 4 was asked to prepare evidence-based review papers on surgical techniques in implant dentistry. Two review papers contained information related to the techniques and biomaterials used in sinus floor elevation:

•Simon Storgård Jensen, Hendrik Terheyden: Bone augmentation procedures in localized defects in the alveolar ridge: clinical results with different bone grafts and bone substitute materials (Jensen and Terheyden 2009)

•Matteo Chiapasco, Paolo Casentini, Marco Zaniboni: Bone augmentation procedures in implant dentistry (Chiapasco et al. 2009)

Definition of terms

The following definitions were adopted from the Glossary of Oral and Maxillofacial Implants (Laney 2007):

•Maxillary sinus floor elevation: An augmentation procedure for the placement of implants in the posterior maxilla where pneumatization of the maxillary sinus and/or vertical loss of alveolar bone has occurred.

•Autograft (synonymous with autologous/autogenous graft): Tissue transferred from one location to another within the same individual.

•Allograft: A graft between genetically dissimilar members of the same species.

•Xenograft: A graft taken from a donor of another species.

•Alloplast: Inorganic, synthetic, or inert foreign material implanted into tissue.

Maxillary sinus floor elevation using the transcrestal technique

Maxillary sinus floor elevation using a transcrestal technique is a predictable procedure for augmenting the bone in the posterior maxilla. A variety of grafting materials can be employed safely and predictably, either alone or in combination. These grafting materials include autografts, allografts, xenografts, and alloplastic materials. At present, it is not clear whether the introduction of a grafting material improves the prognosis.

Maxillary sinus floor elevation using the lateral window technique

Maxillary sinus floor elevation using the lateral window technique is predictable for augmentation of bone in the posterior maxilla. A variety of grafting materials can be used safely and predictably, either alone or in combination. These materials include autografts, allografts, xenografts, and alloplastic materials. The use of autografts does not influence survival rates of rough-surfaced implants but may reduce healing times.

Bone quantity and density in the residual maxilla influence implant survival rates, independently of the type of grafting procedure used.

The survival rates for implants with rough surfaces placed in the augmented maxillary sinus are similar to those of implants inserted in native bone.

2.2	Proposed Clinical Approaches

Maxillary sinus floor elevation using the transcrestal technique

•Sinus floor elevation using the transcrestal technique can be recommended in sites where the alveolar crest is sufficiently wide, initial bone height is 5 mm or more, and the anatomy of the sinus floor is relatively flat.

The main disadvantage of this technique is a risk of sinus membrane perforation, which is difficult to manage. Transcrestal procedures should only be user by clinicians experienced in performing sinus floor elevation using the lateral window technique. Primary implant stability is a prerequisite for this technique.

Maxillary sinus floor elevation using the lateral window technique

•In sites where initial bone height is limited and does not allow implants of the desired length to be placed, sinus floor elevation using the lateral window technique can increase bone height.

•Atrophy of the maxilla occurs three-dimensionally. The edentulous posterior maxilla should not only be evaluated in terms of initial bone height below the maxillary sinus but also in terms of vertical and horizontal deficiencies of the ridge. If a relevant vertical or horizontal intermaxillary discrepancy is present, onlay bone augmentation may be considered to create sufficient bone volume and a proper intermaxillary relationship in order to optimize implant placement and related prosthetic restoration.

•Data related to the initial clinical situation should be reported and defects classified according to well-defined criteria.

•If the initial bone height allows primary implant stability, simultaneous implant placement (one-stage) can be recommended. Where primary stability cannot be achieved, the sinus floor should be elevated in a separate procedure, followed by delayed implant insertion (staged approach).

•Implants should have rough surfaces. Covering the access window with a membrane may be considered.

2.3	Literature Review
	Simon Storgård Jensen

Maxillary sinus floor elevation was comprehensively reviewed as a major topic at the 4th ITI Consensus Conference in August 2008. The following is a summary of the literature that was reviewed during that conference and of additional papers of significance published subsequently.

2.3.1Maxillary Sinus Floor Elevation – Lateral Window Technique

Note: To improve readability, extensive lists of references (referred to by superscript numbers in brackets) are presented separately in Chapter 8.1.

Implant survival

Maxillary sinus floor elevation using the lateral window technique is a well-documented and reliable procedure to increase bone height in the posterior maxilla to allow the placement of dental implants of optimal length. Follow-up data for one year or more after prosthetic loading were included in 85 studies. These studies reported on 4,807 patients with 14,944 implants inserted in augmented sinuses.[1]

Survival rates were 61.2% to 100% (mean: 94.2%; median: 95%) after 12 to 107 months (mean: 31.2 months; median: 29 months) of prosthetic loading. Survival rates of rough-surface implants (plasma-sprayed, acid-etched and/or sandblasted titanium, or HA-coated) were 88....