Tải bản đầy đủ - 0 (trang)
12 Case 4 (Severe Labial Bone Loss with Moderate Gingival Recession)

12 Case 4 (Severe Labial Bone Loss with Moderate Gingival Recession)

Tải bản đầy đủ - 0trang

116



P. R. Klokkevold



a



b



c



Fig. 5.15  Case presentation of an immediate implant placement with immediate (prefabricated) provisional restoration to replace an endodontically failing maxillary left central incisor, #9. (a)

Preoperative clinical photo of maxillary anterior teeth. Notice the maxillary left central incisor area has

drifted coronal and facial. There is a diastema between the right maxillary lateral and central incisor

with flattened interproximal tissue. (b) Preoperative sequential series of clinical photos demonstrating

the treatment steps including extraction, flap reflection, implant placement in palatal position utilizing

a computer-generated surgical guide, bone grafting labial dehiscence defect with particulate bone

allograft, placement of prefabricated provisional restoration, and placement of several layers of L-PRF

membrane. (c) Clinical photograph 1 year later after delivery of final restorations, including crown #8,

implant crown #9, and veneer #10 (Courtesy of Dr. Thomas Han and Dr. Todd Schoenbaum)



5  Soft Tissue Management for Implants in the Aesthetic Zone



117



Conclusions



Aesthetic failures frequently begin with an inadequate examination of the existing soft and hard tissues, which leads to an incorrect diagnosis and ultimately to

an inappropriate treatment plan. The wrong treatment plan combined with selection of inappropriate surgical approaches or techniques can result in poor aesthetic outcomes.

The clinical science in dentistry has evolved to where placement of dental

implants and restoring them requires sufficient knowledge in several disciplines

of dentistry. In addition to mastering surgical objectives and techniques, clinicians must be able to evaluate and accurately diagnose the existing periodontal

condition. Furthermore, proper restorative management of soft tissues is critical

to achieving and maintaining aesthetics. Hence, there are multiple aspects of

diagnosis that are essential for the development of an appropriate treatment plan

necessary for a successful outcome in aesthetic implant dentistry.

The soft tissue management and minimally invasive surgical approach to aesthetics presented in this chapter are based on sound biological principles and

offer a predictable way to preserve and enhance aesthetics of anterior partially

edentulous cases.



References

1.Gargiulo AW, Wentz FM, Orban B. Dimensions and relations of the dentogingival junction in

humans. J Periodontol. 1961;32:261–7.

2.Kan JY, Rungcharassaeng K, Umezu K, Kois JC.  Dimensions of peri-implant mucosa: an

evaluation of maxillary anterior single implants in humans. J Periodontol. 2003;74:557–62.

3. Vacek JS, Gher ME, Assad DA, Richardson AC, Giambarresi LI. The dimensions of the human

dentogingival junction. Int J Periodontics Restorative Dent. 1994;14:154–65.

4.Tarnow DP, Magner AW, Fletcher P. The effect of the distance from the contact point to the

crest of bone on the presence or absence of the interproximal dental papilla. J Periodontol.

1992;63:995–6.

5. Martegani P, Silvestri M, Mascarello F, Scipioni T, Ghezzi C, Rota C, Cattaneo V. Morphometric

study of the interproximal unit in the esthetic region to correlate anatomic variables affecting

the aspect of soft tissue embrasure space. J Periodontol. 2007;78:2260–5.

6.Cho HS, Jang HS, Kim DK, Park JC, Kim HJ, Choi SH, Kim CK, Kim BO. The effects of

interproximal distance between roots on the existence of interdental papillae according to the

distance from the contact point to the alveolar crest. J Periodontol. 2006;77:1651–7.

7. Schoenbaum TR, Klokkevold PR, Chang YY. Immediate implant-supported provisional restoration with a root-form pontic for the replacement of two adjacent anterior maxillary teeth: a

clinical report. J Prosthet Dent. 2013;109:277–82.

8. Buser D, Bornstein MM, Weber HP, Grutter L, Schmid B, Belser UC. Early implant placement

with simultaneous guided bone regeneration following single-tooth extraction in the esthetic

zone: a cross-sectional, retrospective study in 45 subjects with a 2- to 4-year follow-up. J

Periodontol. 2008;79:1773–81.

9.Chen ST, Darby IB, Reynolds EC, Clement JG. Immediate implant placement postextraction

without flap elevation. J Periodontol. 2009;80:163–72.

10.Kan JY, Rungcharassaeng K, Lozada J.  Immediate placement and provisionalization of



maxillary anterior single implants: 1-year prospective study. Int J Oral Maxillofac Implants.

2003;18:31–9.

11.Klokkevold PR, Han TJ, Camargo PM. Aesthetic management of extractions for implant site

development: delayed versus staged implant placement. Pract Periodontics Aesthet Dent.

1999;11:603–10. quiz 612.



118



P. R. Klokkevold



12.Azzi R, Takei HH, Etienne D, Carranza FA.  Root coverage and papilla reconstruction



using autogenous osseous and connective tissue grafts. Int J Periodontics Restorative Dent.

2001;21:141–7.

13.Han TJ, Takei HH. Progress in gingival papilla reconstruction. Periodontol. 1996;11:65–8.

14.Takei HH, Han TJ, Carranza FA Jr, Kenney EB, Lekovic V. Flap technique for periodontal

bone implants. Papilla preservation technique. J Periodontol. 1985;56:204–10.

15.Lekovic V, Kenney EB, Weinlaender M, Han T, Klokkevold P, Nedic M, Orsini M. A bone

regenerative approach to alveolar ridge maintenance following tooth extraction. Report of 10

cases. J Periodontol. 1997;68:563–70.

16.Araujo MG, Lindhe J. Dimensional ridge alterations following tooth extraction. An experimental study in the dog. J Clin Periodontol. 2005;32:212–8.

17.Araujo MG, Wennstrom JL, Lindhe J. Modeling of the buccal and lingual bone walls of fresh

extraction sites following implant installation. Clin Oral Implants Res. 2006;17:606–14.

18.Hammerle CH, Araujo MG, Simion M, Osteology Consensus G. Evidence-based knowledge

on the biology and treatment of extraction sockets. Clin Oral Implants Res. 2012;23(Suppl

5):80–2.

19.Tarnow D, Elian N, Fletcher P, Froum S, Magner A, Cho SC, Salama M, Salama H, Garber

DA. Vertical distance from the crest of bone to the height of the interproximal papilla between

adjacent implants. J Periodontol. 2003;74:1785–8.

20. Kois JC. Predictable single-tooth peri-implant esthetics: five diagnostic keys. Compend Contin

Educ Dent. 2004;25:895–6. 898, 900 passim; quiz 906–897.

21.Benic GI, Mokti M, Chen CJ, Weber HP, Hammerle CH, Gallucci GO. Dimensions of buccal bone and mucosa at immediately placed implants after 7 years: a clinical and cone beam

computed tomography study. Clin Oral Implants Res. 2012;23:560–6.

22. Miron RJ, Dard M, Weinreb M. Enamel matrix derivative, inflammation and soft tissue wound

healing. J Periodontal Res. 2015;50:555–69.

23.Rasperini G, Roccuzzo M, Francetti L, Acunzo R, Consonni D, Silvestri M.  Subepithelial

connective tissue graft for treatment of gingival recessions with and without enamel matrix

derivative: a multicenter, randomized controlled clinical trial. Int J Periodontics Restorative

Dent. 2011;31:133–9.

24. Hehn J, Schwenk T, Striegel M, Schlee M. The effect of PRF (platelet-rich fibrin) inserted with

a split-flap technique on soft tissue thickening and initial marginal bone loss around implants:

results of a randomized, controlled clinical trial. Int J Implant Dent. 2016;2:13.

25.Han TJ, Jeong CW. Bone and crescent shaped free gingival grafting for anterior immediate

implant placement: technique and case report. J Implant Adv Clin Dent. 2009;1:23–33.

26.Araujo MG, Sukekava F, Wennstrom JL, Lindhe J.  Ridge alterations following implant

placement in fresh extraction sockets: an experimental study in the dog. J Clin Periodontol.

2005;32:645–52.

27.Nevins M, Camelo M, De Paoli S, Friedland B, Schenk RK, Parma-Benfenati S, Simion M,

Tinti C, Wagenberg B. A study of the fate of the buccal wall of extraction sockets of teeth with

prominent roots. Int J Periodontics Restorative Dent. 2006;26:19–29.

28.Chiapasco M, Consolo U, Bianchi A, Ronchi P. Alveolar distraction osteogenesis for the correction of vertically deficient edentulous ridges: a multicenter prospective study on humans.

Int J Oral Maxillofac Implants. 2004;19:399–407.

29. Covani U, Cornelini R, Barone A. Bucco-lingual bone remodeling around implants placed into

immediate extraction sockets: a case series. J Periodontol. 2003;74:268–73.

30.Schropp L, Kostopoulos L, Wenzel A.  Bone healing following immediate versus delayed

placement of titanium implants into extraction sockets: a prospective clinical study. Int J Oral

Maxillofac Implants. 2003;18:189–99.

31.Allen EP, Gainza CS, Farthing GG, Newbold DA.  Improved technique for localized ridge

augmentation. A report of 21 cases. J Periodontol. 1985;56:195–9.

32. Seibert JS. Treatment of moderate localized alveolar ridge defects. Preventive and reconstructive concepts in therapy. Dent Clin N Am. 1993;37:265–80.



5  Soft Tissue Management for Implants in the Aesthetic Zone



119



33.Kan JY, Rungcharassaeng K, Lozada JL. Bilaminar subepithelial connective tissue grafts for

immediate implant placement and provisionalization in the esthetic zone. J Calif Dent Assoc.

2005;33:865–71.

34. Khzam N, Arora H, Kim P, Fisher A, Mattheos N, Ivanovski S. Systematic review of soft tissue

alterations and esthetic outcomes following immediate implant placement and restoration of

single implants in the anterior maxilla. J Periodontol. 2015;86:1321–30.

35. Kan JY, Rungcharassaeng K. Site development for anterior single implant esthetics: the dentulous site. Compend Contin Educ Dent. 2001;22:221–6. 228, 230-221; quiz 232.

36. Bengazi F, Wennstrom JL, Lekholm U. Recession of the soft tissue margin at oral implants. A

2-year longitudinal prospective study. Clin Oral Implants Res. 1996;7:303–10.

37.Grunder U.  Stability of the mucosal topography around single-tooth implants and adjacent

teeth: 1-year results. Int J Periodontics Restorative Dent. 2000;20:11–7.

38.Nozawa T, Enomoto H, Tsurumaki S, Ito K. Biologic height-width ratio of the buccal supra-­

implant mucosa. Eur J Esthet Dent. 2006;1:208–14.

39.Kan JY, Rungcharassaeng K, Lozada JL, Zimmerman G. Facial gingival tissue stability following immediate placement and provisionalization of maxillary anterior single implants: a

2- to 8-year follow-up. Int J Oral Maxillofac Implants. 2011;26:179–87.



6



Growth Factors for Site Preparation:

Current Science, Indications,

and Practice

Tara Aghaloo and Rachel Lim



Abstract



Implant restoration of the dentition poses many challenges in cases of limited

bony foundation. Many patients suffer from loss of teeth and supporting bony

structures through mechanisms including trauma, congenital abnormalities, or

resorption secondary to tooth loss. In addition to classic alveolar ridge augmentation techniques and materials, growth factors are being studied to improve

patient outcomes, especially in cases of larger, more challenging defects, in previously failed graft sites, and in stringent aesthetic cases. In this chapter, we will

discuss three growth factors which are most commonly studied and US Food and

Drug Administration approved: bone morphogenetic protein-2 (BMP-2), platelet-derived growth factor (PDGF), and platelet-rich protein/platelet-rich fibrin

(PRP/PRF). Currently, growth factors are utilized in a wide variety of clinical

situations, including guided bone regeneration, peri-implant defects, sinus augmentation, and socket augmentation. Furthermore, we will explore the future of

growth factor usage, with new factors in various stages of investigation, combinations of materials, and viable cell therapy. Though much work has been done

in the last few decades to reveal the clinical relevance of growth factors, much

more research, both basic and clinical, must be performed to improve current

technologies, develop predictable protocols, and evaluate long-term results.



T. Aghaloo (*)

Section of Oral and Maxillofacial Surgery, UCLA School of Dentistry,

Los Angeles, CA, USA

e-mail: taghaloo@dentistry.ucla.edu

R. Lim

Department of Oral and Maxillofacial Surgery, University of Washington, Seattle,

WA, USA

© Springer International Publishing AG, part of Springer Nature 2019

Todd R. Schoenbaum (ed.), Implants in the Aesthetic Zone,

https://doi.org/10.1007/978-3-319-72601-4_6



121



122



6.1



T. Aghaloo and R. Lim



Introduction



Many patients suffer from significant loss of the periodontium and surrounding

bony structures through mechanisms including periodontal disease, trauma, congenital abnormalities, tumors, or resorption secondary to tooth loss. In these situations, achieving a stable site for reconstruction through implant placement can pose

clinical challenges and may require augmentation to optimize the supporting structures [1]. Furthermore, aesthetic zone sites require more stringent planning, with

factors such as gingival biotype and space limitations significantly affecting the

final result, and in which proper placement of the implant is paramount to an ideal

outcome [2]. In smaller bony defects, successful treatment with guided bone regeneration (GBR; see Chap. 4) using autografts, allografts, or xenografts has been well

documented [3]. However, larger or more challenging defects in previously failed

graft sites or implant sites in medically compromised patients will require more

complex therapy to achieve a successful outcome. In such cases, traditional techniques and materials may not achieve sufficient bone regeneration, compromising

the prosthetic rehabilitation and final outcome.

One of the main techniques that have been implemented since its development in

the 1980s is guided bone regeneration, which has resulted in predictable regeneration of contained defects through usage of grafting materials and/or barrier membranes [1, 3]. In cases requiring significant bone regeneration, secondary techniques

have been employed concurrently with GBR to overcome limitations of scaffold

material and to recruit the desired cell types for regeneration. Over the past decade,

molecular mediators, such as growth factors, have been extensively studied for their

potential to combat challenging clinical scenarios by accelerating the healing process and aid in regeneration of the missing maxillofacial tissues [4]. Growth factors

naturally occur in the body and are capable of stimulating growth, proliferation, and

differentiation of cells. Growth factors regulate many of the key cellular events that

are required for tissue repair and regeneration. The clinical application of these

biologic agents aims to provide faster healing, implant osseointegration, and expedited establishment of functionality. Currently, growth factors are utilized in a wide

variety of clinical situations including intrabony defects, barrier membranes for

GBR, peri-implant defects, sinus augmentation, and socket augmentation. In this

chapter, we will focus on US Food and Drug Administration (FDA)-approved

growth factors: bone morphogenetic protein (BMP-2), platelet-derived growth factor (PDGF), and platelet-rich plasma (PRP)/platelet-rich fibrin (PRF).

Bone forms through three distinct mechanisms, and bone grafting materials are

classified based on their ability to activate these mechanisms. Osteoconductive

materials possess the ability to passively act as a scaffold and allow substitution of

new bone. Osteoconduction requires good surrounding bone that can be resorbed

and replaced with new native bone from the host. Although osteoconductive materials are readily available and inexpensive, large and complex bone defects or medically compromised patients with poor healing potential generally cannot regenerate

bone from only scaffold grafting material. Osteoinductive materials can actively

recruit undifferentiated mesenchymal stem cells to the graft site and stimulate



6  Growth Factors for Site Preparation: Current Science, Indications, and Practice



123



osteoblastic differentiation. Bringing these cells to the site and driving bone formation is a huge advantage of inductive materials. However, most off the shelf bone

grafts do not contain these properties. Osteogenic materials transplant live bone

cells which can actively form new bone at the recipient site [5]. Osteogenesis is the

most powerful of the three mechanisms, but only autogenous bone possesses these

properties. Unfortunately, not all patients are candidates for autogenous bone harvesting since it often requires a second surgical site, increased morbidity, and longer

surgical time. When determining the appropriate growth factor for a specific patient,

evaluating the bone or soft tissue enhancing properties of the material is important.

Since no graft material can possess all the ideal properties—biocompatibility, biodegradability, promotion of vascularity, mechanical properties similar to bone,

selectivity for osteogenic cell adherence and survival, ease of manipulation, availability, and low cost—growth factors may improve or enhance our currently utilized

materials.



6.2



Bone Morphogenetic Protein-2 (BMP-2)



Bone morphogenetic proteins (BMPs) are secreted glycoproteins that belong to the

transforming growth factor-beta (TGF-β) superfamily. These glycoproteins are classified as morphogens, with roles in dictating tissue patterning in embryonic development, and are potent regulators of bone and cartilage formation and repair. Many

studies have demonstrated that BMP’s can induce mesenchymal stem cell differentiation into bone and cartilage, making them promising molecules for tissue engineering and bone therapy [6]. In 1965, Urist first discovered BMP as a substance in

the extracellular bone matrix which was capable of inducing ectopic osteogenesis

when implanted in extraskeletal rabbit muscle pouches [7]. Since the classification

of BMP’s in the late 1980s, more than 20 members have been identified, though not

all are osteogenic [8, 9]. Specifically, BMP-2 is most commonly utilized for its

osteoinductive properties, which allows it to actively promote chemotaxis to the

graft site and stimulate osteoblastic differentiation and bone formation [10, 11].

BMP-2 has been extensively studied and increasingly applied in orthopedic surgery

to improve the results of bone therapy. In 2002, recombinant human BMP-2 and

BMP-7 (rhBMP-2 and rhBMP-7) were approved by the FDA for orthopedic applications including (1) promoting fusion of lower spine vertebrae, (2) acute tibia fractures, and (3) tibia nonunion [12]. As patients become more medically compromised

or when conventional grafting techniques fail, growth factors have been utilized for

new applications such as posttraumatic osteonecrosis of the femoral head [13].

In oral and maxillofacial reconstruction, BMP-2 has demonstrated ability to control bone formation, contour, and density through endochondral formation [1].

Randomized clinical trials demonstrate predictable bone formation in  localized

alveolar bone defects associated with tooth extraction and sinus augmentation when

placed on an absorbable collagen sponge (ACS) [14–16]. These successes led to

FDA approval for these dental indications in 2007 (Infuse, Medtronic, Nashville,

TN). Since its approval, clinicians and researchers continue to expand the off-label



124



T. Aghaloo and R. Lim



uses of rhBMP-2/ACS to include onlay grafting, lateral ridge augmentation, extensive maxillofacial reconstruction, and mandibular continuity defects (Fig. 6.1) [4,

17–25]. These more complicated defects generally require a more compressive

resistant scaffold (such as titanium mesh) [26, 27].

rhBMP-2/ACS is often combined with a xenograft or allograft for alveolar ridge

or sinus augmentation, resulting in further off-label utilization (Fig. 6.1) [27–32]. In

addition, improved soft tissue compression resistance can be obtained by combining

rhBMP-2/ACS with additional graft materials or titanium mesh. Specifically, combination with osteoconductive materials may decrease the BMP-2 dose needed to

regenerate bone defects. Clinically FDA-approved supraphysiologic BMP-2 doses

have been associated with many side effects including major swelling, inflammation, seromas, wound breakdown, heterotopic bone formation, cystic bone cavities,

immunogenicity, BMP antibody formation, osteolysis through osteoclast activation,

and bone cyst formation [33–39]. Currently, BMP-2 use for oral and maxillofacial

defects has not been optimized due to high costs, nonideal carriers, and suboptimal

bone formation, resulting in limited clinical use. However, in patients with

a



b



c



d



e



f



g



h



i



j



k



l



m



n



o



p



Fig. 6.1  rhBMP-2 for anterior maxillary ridge augmentation. (a) Buccal and (b) occlusal view of

resorbed alveolar ridge with temporary fixed partial denture. (c) Clinical and (d) radiographic

(CBCT cone-beam CT scan) preoperative alveolar ridge. (e) After flap reflection, (f) cortical bone

decortication is performed to release undifferentiated mesenchymal stem cells from the trabecular

bone that can respond to the rhBMP-2. (g) rhBMP-2/ACS is combined with autograft and alloplast

grafting materials and covered with a (h) BMP-2 sponge before (i) titanium mesh is applied to

resist soft tissue compression. (j) Wound healing after 7 months and (k) CBCT scan before implant

placement. (l) Titanium mesh is seen at the time of implant placement for removal and reveals (m)

an increased volume of bone for (n) implant placement. (o) Adequate ridge dimensions are seen,

and (p) soft tissue coverage is performed without difficulty



Tài liệu bạn tìm kiếm đã sẵn sàng tải về

12 Case 4 (Severe Labial Bone Loss with Moderate Gingival Recession)

Tải bản đầy đủ ngay(0 tr)

×