Page 10 - GP Spring 2022

Bone Augmentation and Implant Restoration in a
Compromised Aesthetic Zone: A Case Report

By Omid Termechi, DDS and Sleiman N. Razzouk, DDS, MS, PhD

Abstract GBR grafting is one solution for such prob- Allograft
lems and can be broken into two forms: Allografts are bone grafts obtained from the
Purpose: This case report describes four block and particulate onlay grafting. The same species but are genetically dissimilar
routine treatment modalities for single im- latter can further be divided into two cat- from the host. These materials go through
plant placement in the aesthetic zone. The egories: tunnel and direct particulate onlay an intense preparation process, including
protocol can be standardized to achieve grafting. In this clinical case, we performed freeze-drying, to prevent the transmission
the same result on similar cases in daily onlay particulate GBR grafting. of diseases. Mineralized allograft (MA)
practice. This paper presents the staging provides stability, space maintenance, and
of the treatment plan for any patient with Technique osteoconductive scaffolding to increase
deficient hard and soft tissues to achieve a GBR procedures can either be staged or volume enhancement in the GBR site for
beautiful result. simultaneous with implant placement. The successful implant placement. MA is com-
host area is fully exposed with a full-thick- posed of cortical and cancellous bone. The
Keywords: Guided Bone Regeneration ness flap to visualize the defect. It is imper- cortical portion has a slower resorption rate
(GBR), Guided Tissue Regeneration ative to create a tension-free soft tissue flap than the cancellous component; therefore,
(GTR), polytetrafluorethylene (e-PTFE), by using releasing incisions on both sides in a case where the clinician requires the
aesthetic zone, implant, periodontal de- of the flap to increase site visibility and en- material to stay longer without resorption
fect, bone defect, membrane, onlay graft, sure a tension-free flap closure. to act as a scaffold, they can increase the
allograft, xenograft. percentage of the cortical component in
GBR Considerations the bone mixture. MA can be mixed with
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Materials and methods: Single case study The essential purpose of the GBR is to ex- DBB material in order to slow the process
patient, treated by the same clinician, sur- clude the epithelial cells, which have a high of resorption down even further.
gically and restoratively, who had large turnover rate, and to allow the migration
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bone and soft tissue defects in the aesthetic of the osteoblastic cells to the site. This The other important part of the GBR tech-
zone. These treatment modalities included: includes using a biological membrane to nique is the membrane. The membrane
1) Guided bone regeneration (GBR) with isolate the two compartments: soft tissue isolates the bone graft material from soft
e-PTFE and platelet-rich fibrin (PRF), 2) and bone particles. The main bone grafting tissue invasion. There are two types of
Guided Tissue Regeneration (GTR), 3) substitutes include autogenous bone, xeno- membranes available: resorbable and
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Implant placement and interim provisional graft, allograft, and alloplast. The ideal non-resorbable. The membrane needs to
restorations after the implant was fully os- bone material will create a balance between provide a barrier, be biocompatible and be
seointegrated, and 4) Final screw-retained resorption and formation of new osteogenic easy to use. They also need to have bio-
restoration. cells in the area of the GBR. In addition, active properties in order to promote and
space is required by the material in order for enhance tissue regeneration. Synthetic
Introduction: Implant placement has be- healing to occur. Autogenous bone is the polymers are used to manufacture non-bio-
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come the preferred treatment method for gold standard due to its osteogenesis, oste- degradable membrane materials, both with
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the anterior maxillary area when a tooth oinduction, and osteoconduction abilities. and without a metal component. The metal
is missing due to its high success rate and component may be added to increase the
ability to restore the region without involv- Xenograft or Deproteinized Bovine Bone integrity and to enhance the membrane’s
ing the neighboring teeth. Osseointegration (DBB) space maintaining ability. The first non-re-
has become less of an issue with the latest Xenograft bone materials come from cows, sorbable membrane that was introduced
generations of dental implants. However, horses, or species other than humans. to the market was made from expanded
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the aesthetic zone is still a big challenge to Xenografts are frequently used in GBR polytetrafluoroethylene (e-PTFE). The
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the practitioner. Success in this region with procedures today. These materials are os- second type of membrane is a biodegrad-
implant therapy is heavily dependent upon teoconductive and have an interconnect- able membrane, made from natural and
the positive appearance and correct harmo- ing pore system that serves as a scaffold synthetic polymers. Collagen is one of the
ny with the remaining dentition. Therefore, for the migration of the osteogenic cells. most commonly used materials in these
different parameters need careful consider- The advantage of the DBB graft is that it membranes and is made by cross-linking.
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ation, such as the soft tissue condition, vol- has close molecular similarities to human New materials such as aliphatic polyesters
ume, color, contour, and the surrounding natural cortical bone. DBB particles are and other copolymers have recently been
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zeniths. Various conditions cause periodon- incorporated into the living bone over time introduced into GBR procedures. In addi-
tal tissue defects, and the goal is to reestab- and have a low turnover or substitution tion, inorganic materials such as calcium
lish the original environment with surgical rate. Therefore, it provides long-term space phosphate and bioactive glass are being
procedures such as GBR and GTR. maintenance which is an essential part of researched to help the membrane’s regen-
any successful bone graft. It has been erative abilities and strength. The main
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GBR and GTR can be performed simulta- shown that DBB graft particles remain advantage of the resorbable membranes is
neously with implant placement depending present even ten years after placement. to eliminate a second surgical procedure
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on the amount of bone loss and the volume One should be aware that it can be detri- to remove the membrane, which would
of soft tissue present. This volume defi- mental to the future of the implant if there reduce the morbidity of the procedure and
ciency of bone and soft tissue can be either is excessive DBB contact with the implant lower the rate of complications. However,
anatomic or pathologic. instead of the patient’s own vital bone.
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