Soft tissue

ridge

augmentation

Darshanaa A

III yr PG

Contents

– Definition

– Classification

– Indications

– Contraindications

– Materials used

– Soft tissue and esthetic considerations before ridge augmentation procedure

– Techniques

– Techniques used during 1st and 2nd stage implant therapy

Definition

– Ridge augmentation is a periodontal procedure used to repair the deficient

edentulous ridge

It can be corrected by

– Hard tissue only

– Soft tissue only

– Soft and hard tissues

Classification

Sieberts classification (1983)

– Class 1 – buccolingual loss of tissue with normal ridge height in the apicocoronal direction

– Class 2 - apicocoronal loss of tissue with normal width in the buccolingual direction

– Class 3 – combination buccolingual and apicocoronal loss of tissue, resulting in loss of normal height and width

Allens classification

– Mild - less than 3 mm reduction

– Morderate - between 3 to 6 mm reduction

– Severe - more than 6 mm reduction

Indications

– Deficiency in alveolar ridge due to periodontal disease, loss of teeth, trauma,

neoplasm

– Pronounced concavity and loss of emergence profile in single tooth implant

Contraindications

– Systemic conditions – applicable to all surgeries

– Collagen disorders – eg. Lichen planus, pemphigoid. Due to its pathologic

healing mechanism

– Smokers – success of a graft thrives on vascularity. Smoking hampers with the

vascularity of graft due to the vasoconstrictive effect of nicotine

Materials used

– Autogenous graft

• Free gingival graft

• Connective tissue graft

– Allograft

– Xenografts

Free gingival graft

– First used graft

– Reliable and efficacious

– High and predictable success rate

– Used to increase amount of keratinized tissue (rocuzzo M et al., 2007)

– Gold standard procedure when keratinisation is needed

– Mostly taken from palatal area

– Used as rescue procedures, in place of high smile line, when there is a need for extensive soft tissue augmentation and where there is no esthetic concern

Disadvantages

– “Patch like appearance” – colour doesn’t blend with the adjacent tissues. Kills the purpose of esthetics

– High morbidity

– Less amount of tissue available

Connective tissue graft

– Overcomes the esthetic drawback of FGG. Good colour match

– Gold standard when it comes to recession coverage procedures in esthetic areas (Imberman M et al., 2007)

– Good vascularity

– Controversy over attachment with implant surface

Drawbacks

– High morbidity

– Lack of adequate tissue in the case of a large defect

Allografts

– Commonly used allografts

• Acellular dermal matrix

• Human fibroblast derived dermal derivative

– Low morbidity

– Results in good amount of KT (Hamerle CH et al., 2002)

Disadvantages

– Taken from cadaver specimens – ethical issues

– High risk of disease transmission

xenografts

– Commonly used – collagen membrane of porcine origin (Tradename : MUCOGRAFT™)

– Overcomes the drawbacks of allografts

– Low risk of disease transmission and low morbidity (Jung RE et al., 2011)

– Esthetic results

– Good amount of tissue availability

– Clinical results comparable to gold standard CTG (Barone R et al., 1998)

– Mechanism of action – forms a scaffold into which fibroblasts, blood vessels and surrounding epithelial cells migrate and transform into KT

Soft tissue expanders

– Soft tissue expansion is a technique used by plastic surgeons to cause a body to

grow additional bones, tissues, or skin.

– 2 types

• Silicon balloons

• Osmotic tissue expanders

Silicone baloons

– It is costume made according ti the area and expansion needed

– Made of medical grade silicone

– The liquid is injected externally through a liquid processing unit

– Placed under the tissue

– After the volume is achieved it is substituted by graft materials

– Technique sensitive

– Decreased swelling and less discomfort

Osmotic tissue expanders

– Self filling

– Made of polymers methyl methacrylate enclosed in a silicone sheathe

– Perforations can be made according to how much expansion is needed

– Absorbs tissue fluid through osmosis and expands

– Requires refining of surgical technique

– Easy augmentation

– High tissue gain

– Need for external filling eliminated

– Minimal complications

Soft tissue and esthetic considerations

before ridge augmentation procedures

Rationale

– Transmucosal seal

– Esthetic appearance

– Good emergence profile

– Convexity to simulate root prominence

– To withstand prosthetic mechanical challenge

– Good contour

– Self cleansing

– Withstand recession

Biology

periimplant and periodontal mucosa are mostly similar

– contain an epithelial component and connective tissue component

– Contains junctional epithelium

– Collagen type 1 is the predominant fibre in the supracrestal region

– Similar distribution of collagen type 1 3 4 7 and fibronectin (Chavrier CA et al., 1999)

– Less vascular area close to implant analogous to cicatricial fluid (Berglundh T et al., 1996)

– Periimplant tissue similar to scar tissue

Dissimilarities

– Length of junctional epithelium is longer in periimplant mucosa

– Collagen type 5 found to be higher in periimplant tissue (Chavrier CA et al., 1999)

– Fewer fibroblasts in periimplant mucosa than in gingival tissues

– Collagen fibres run parallelly in periimplant mucosa, but attach perpendicular to the cementum in

periodontal mucosa (Berglundh T et al., 1991)

– Periimplant mucosa resembles scar tissue without supracrestal fibres insertion into cementum

Biological width

– Bone requires a minimum of 1.5 connective tissue component and 2 mm

epithelial component (Berglundh T et al., 1991, 1994)

– The entire contact length between implant/ cementum, connective tissue and

implant constitute the biological width

– The minimum width is required, failing which the biological width is tried to be

reestablished by bone loss (Berglundh T et al, 1996)

– Same trait is found in loaded and unloaded conditions (Siar CH et al., 2003)

– Same trait is found in both one part and two part implants (Abrahamson I et al.,

1996)

Soft tissue health

– Soft tissue integrity is essential before any prosthetic replacement (Kan JY et al., 2003, Zigdon H et al., 2008)

Soft tissue health is affected by

– Thickness of tissues – different thickness respond differently to inflammation. Thin tissues are more prone to inflammation and recession (Maynard JG Jr et al., 1979, Kan JY et al., 2003)

– Amount of tissue surrounding bone – a minimum of 2 mm is required to avoid supra crestal bone loss

– Amount of bone surrounding an implant – 1.8 mm of bone is required to surround an implant (Spray JR et al., 2000)

– interimplant distance – 3 mm is required (Tarnow DP et al., 2000, 1992)

– Distance between contact area of clinical crown and crestal bone – if its is less than 5mm there will be 100 percent interdental coverage with papilla formation

– Full thickness flaps amount to an average of 1 mm crestal bone loss in height and width (CardoropoliG et al., 2006)

Keratinized tissue

– Adequate Keratinized tissue is a requirement for any prosthetic procedure

– KT is a dense, collagen rich tissue with keratinised with firm attachment of underlying lamina propria to the bone (Ten Cate AR AROral histology development structure and function)

– Alveolar Mucosa is less dense, with less collagen tissue with non keratinised epithelium with loose attachment to the musclesunderneath

– KT is required to resist recession, inflammation. Greater keratinised tissue around a prosthesis gives greater clinical parameters and better longterm prognosis and maintenance of the prosthesis (Adibrad M et al., 2009, Thoma DS et al., 2014)

– Lining mucosa is more prone to detachment, recession and inflammation. Reduced with of KT indicates shallow vestibule, thus leads to plaque accumulation and inflammation

– In patients with good oral hygiene, less than 2 mm width of attached gingiva caused lingual plaque accumulation, bleeding and soft tissue recession over a period of 5 years (Schrott AR et al., 2009)

– Adequately keratinized zone of masticatory mucosa for good oral heath is <2mm of masticatory gingiva and >1mm of attached gingiva in 5 years (Chung DM et al., 2006)

– KT should be created with mucogingival techniques prior to implant placement if not present in adequate amounts (Wennstrom JL et al., 2012)

– Importance of KT is controversial. (Karring T et al., 1971, Wenstrom J et al., 1983) It may not be crucial for maintenance of soft tissue health (Cairo F et al., 2007) and bone loss (Chung DM et al 2006)

Mucosal thickness

– A minimum of 3 mm mucosa. Otherwise bone loss occurs to compensate the biological width

– Linkeviscious et al., in his study found that bone loss was greater (1.45mm) in subjects with thin gingival biotype (<2.5mm) than in subjects with thick biotypes (>2.5mm).

– “Black triangle” causes difficulty in phonetics, food accumulation and unpleasant esthetic (Chow YC et al., 2010)

– Greater than 2.5 mm thickness of gingiva warranted better formation of soft tissue contour and papilla

– It also depended on interdental distance, distance from crest to contact area, tooth form and contour, mucosal thickness, amount of KT

Abutment material

– Titanium has always traditionally been used as the gold standard for its well

documented biocompatibility and mechanical properties

– Abbrahamson et al analysed the soft tissue healing and has shown that titanium

and ceramic promotes good soft tissue attachment whereas gold alloy and

porcelain failed to promote soft tissue attachment. But there was no difference

in terms of microbial sampling

Crest module and abutment

design/surface

– Crest module is the part of implant that receives crestal stress of implant after loading

– It was found that irrespective of its distance from the crest, the crestal bone loss reached till the first thread of implant (Jung YC et al., 1996)

– Hypothesis - The change from sheer force to compressive force by the crest module caused the bone loss to slow down at that area (Jung YC et al., 1996)

– In an animal study, Micro grooved design showed better soft tissue response and bone implant contact than micro textures and turned surface

– Pacora et al in a 3 year post operative result reported that Laser lock surface treatment reduces crestal bone loss by 0.59 mm

Pink/ White esthetic score

– Can be Used to measure the esthetic value of a prosthesis (Cosyn J et al., 2013)

– The soft tissue color blend, contour, formation of interdental papilla, and

coverage of recession contributes to the esthetic value of a soft issue procedure

– Esthetic outcome is vital for clinical outcome (Cosyn J et al., 2013)

– CTG is required in 1/3rd patients undergoing prosthetic management to increase

PES score (Gu YX et al, 2015)

– Soft tissue augmentation in the second stage of the implant increases PES score

in short term follow up but reverts back when observed for 3 years (Dorfman HS

et al., 1982)

Soft tissue healing

– Graft uptake and healing requires 6 to 8 weeks

– The graft after healing and taking up post surgery mimics the gingival scar tissue

in composition, fiber orientation and vasculature

Techniques

– Full thickness soft tissue onlay graft (Meitzer 1979)

– Pouch procedure (Garber and Rosenberg 1981)

– Improved technique ( allens modification 1985)

– Subepithelial connective tissue graft (Langers method 1980)

– Interpositional graft (Siebert 1990)

– Interpositional onlay graft (Siebert 1992)

– Azzi modification 1991

– Pediculated connective tissue graft (Sclar 2003)

– Roll technique

– Modified papilla preserving roll procedure

– Meltzer 1979 published first clinical report

– To correct esthetic anterior vertical ridge defect

– Siebert 1983 published a series of classic articles that detail the technique and

applications

Full thickness soft tissue onlay

graft

Pouch procedure

– Garber and Roenberg 1981 developed this technique

– For treating ridges that had a horizontal loss o dimension

– Provides stabilisation of graft and ridge enhancement

– It is a refinement and advancement of the technique devised by langer and

abrams

Ridge augmentation - Improved

technique

– In 1985, allen and colleagues improved a surgical technique for localised ridge

augmentation that was similar to the technique by kahldahl and colleagues

1982 except that the graft material was HA graft

– It permits unlimited donor source

– Greater predictability of results

– Langer and calagna 1980 1982 designed a procedure that combined partial thickness flap anda connective tissue graft.

Advantages

– Versatility

– Primary closure

– Vascularity

– Combined with adjacent root coverage procedures

– Reduced trauma

Disadvantages

– Technically difficult

– Possible need for secondary mucogingival surgery owing to altered coronal position of mucogingival junction

Indication

– For correction of all types of ridge deformitues

Subepithelial connective tissue

graft

– Its is given by siebert 1992

– Almost identical to the pouch procedure

– except that a thick connective tissue graft or wedge is positioned between the

free edge of the pouch and the exposed portion of t he ridge

– Used for treatment of class 1 ridge defects

Interpositional graft

– Siebert and Louis 1995 96 developed this procedure

– For large class 3 ridge defects

– Meant to combine the best procedures of the interpositional graft and the onlay graft into one procedure

Advantages

– Increased revascularization of onlay graft

– smaller platal wound

– Less morbidity

– Increased ability to control direction of augmentation

• Apicocoronal

• Buccolingual

– No alteration in vestibular depth

Interpositional onlay graft

– Papillary reconstruction is unpredictable with minimum results

– Most reports are in the form of individual case reports (takkei 1996, azzi and

colleugues 1999 2001)

– Neurovsky 2001 presented a case series with consistent improvement

– All procedures are the modification of the takei 1996 procdure

Azzi modification

– It si a vascularised subepithelial connective tissue graft designed for esthetic reidge augmentation befire, during and after implant placement

– Will help prevent premature membrane exposure

– Provide sufficient additional vascularized tissue

– For vertical and buccal ridge augmentation

– Involves passive rotation of an interpositional periosteal retained connective tissue flap over the edentulous area into the buccal surface

Advantages

– Maintains intact vascular supply

– Allows large volume of soft tissue augmentation

– Excellent esthetic results

– Minimum post surgical shrinkage

– Primary wound closure

– Reduced morbidity

– Enhanced bone graft maturation

– Predicatble implant site development

Requirements

– Minimum pedicle width 10 mm

– Minimum buccal extension 4mm beyond ridge crest

– Adequate palatal vertical height

– Adequate palatal thickness

Pediculated connective tissue graft

Roll technique

Modified papilla preserving roll

procedure

Techniques used during implant

placement

– Improved technique

– Interpositional graft

– Pediculated connective tissue graft

Techniques used during second

stage implant therapy

– Roll technique

– Modified papilla preserving roll procedure

References

– Edward S Cohen : ATLAS OF COSMETIC AND RECONSTRUCTIVE PERIODONTAL

SURGERY

– Mamdouh Karima, Serge Dibart : PRACTICAL PERIODONTAL PLASTIC SURGERY

– Joann Paulin George et al., Soft tissue and esthetic considerations ., Journal of

the international clinical dental research organization (J Int Clin Dent Res Organ

2015;7:119-31)

– Andreas L Ioannou et al., Soft tissue surgical procedures for optimizing anterior

esthetics., International Journal of dentistry (Volume 2015, Article ID 740764, 9

pages)