Transcript Soft Tissue Changes Associated with Orthognathic Surgery

Soft Tissue Changes Associated with
Orthognathic Surgery
By David R. Telles
Diplomate of the American Board of Oral and
Maxillofacial Surgery
Introduction
 Overview
 Orthodontic considerations
 Movement of dentition
 Maxillary Movements
 Mandibular Movements
 Surgical Techniques
Introduction
 Necessary to include a component of soft tissue changes in
the surgical treatment plan while working to achieve a stable,
functional dentoskeletal unit
 the surgical procedures -- to control the soft tissue changes
will be presented and evaluated
 help the surgeon understand, control, and maximize the
beneficial aspects of the facial soft tissue response to surgery.
Historically
 Orthognatic surgery -- used to correct skeletofacial deformities
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and the resultant functional problems, often at the expense of the
facial soft tissue esthetics
Early studies produced average ratios – which related hard/soft
tissue landmarks
Individual variability noted to be significant
Facial soft tissue response to orthodontics and Sx was
MultiFactorial
Prediction equations developed to help preop evaluation for
surgical planning and post-op assessment
Recent development of surgical procedures to control soft tissue
response to Sx: alar cinch suture and VY closure
Orthodontic Considerations
 Tooth position and alveolar morphology result from the sum
of applied forces during their development
 Skeletal imbalances are accompanied by soft tissue
imblanaces – result = dental compensation for skeletal
malocclusions
 Corrections initially result in worsening of the malocclusion
preoperatively + jaw-jaw discrepency to appear more severe
 Pre-op records to be taken as close to Sx to determine softtissue outcome
Cephalometric Considerations
 Must allow for visualization of the complete soft tissue
profile
 Instruct pt to keep lips in repose for cephs
 Superimpose landmarks that remain unchanged
 Presence of ortho hardware changes the lip profile
Cephalometric Landmarks
Soft Tissue Considerations
 To predict soft/hard tissue changes is critical to Tx planning for
orthognathic Sx
 Changes depending on
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surgical procedure
method of wound closure
the new spatial arrangement of the skeletal/dental elements
adaptive qualities of soft tissues
Growth
orthodontic vectors o ftooth movement
lip thickness. tonus, area, contact (competence), strength
interlabial gap
amount of overjet
amount offatty tissue
Musculature
postoperative edema.
Soft Tissue Considerations
 Stabilize in approx 6 months – some studies suggest 12 months
 Surgical Approach
 Incision type may play a role – horizontal incision for the Le Fort I
osteotomy may cause shortening of the lip
 With loss of vermillion
 Decrease in lip thickness
 Vertical approach with tunneling and palatal flap shows minimal
post-op lip changes
 Betts et. Al. – investigated soft tissue response to Max Sx – found
soft tissue changes may be more related to type/position of
incision and method of closure than surgically induced hard tissue
change
Soft Tissue Considerations
 Will mirror changes in the bony foundation should relapse
occur
 Thin lips move more predictably than thick lips
 “dead space” under the lip may absorb the first portion of a bony
advancement before soft tissue affected
 Horizontal Changes – in soft tissue more predictable than
vertical changes
 Related to the stability of the hard tissue movements (less stable
in vertical dimension)
Soft tissue – assoc. Orthodontic tooth
movement
Maxillary surgical procedures
 Most are soft tissue changes manifested in:
 Nasal
 Labial
Maxillary surgical procedures – Nasal
 Affects lower aspect of the nasal dorsum
 Widening of the alar base regardless of vector of movement
 Shortening of the columellar/alar height
 shortening of the nasal tip projection
 Nasolabial angle decreases or remains constant
Maxillary surgical procedures – Nasal
 Superior movement
 Elevation of the nasal tip
 Widening of the alar base
 Decreased nasolabial angle
 Inferior repositioning
 Loss of nasal tip support
 Downward movement of columella and alar bases
 Thinning of the lip
 Increase in NL angle
Maxillary surgical procedures – Nasal
 Anterior
 Advancement in the
 upper lip
 Subnasale
 Pronasale
 Thinning of the lip
 Widening of the Alar base
 Increase in Supratip break if ANS in tact
 ***Nasal tip advances approx ½ the distance of the
subnasale*******
 Counter clockwise rotation – raises the nasal tip
 Clockwise rotation – decreases superior movement of the nasal tip
Maxillary surgical procedures – Nasal
Maxillary surgical procedures – Labial
 Upper lip is attached to the nose – prevents 1:1 soft tissue
change
 Widens and lengthens at the philtral
columns after Max Sx
 w/o VY closure – can cause shortening
of the upper lip with loss of exposed
vermillion
Maxillary Advancement
 Greatest effect on the nose/upper lip
 Ppts adv of upperlip, subnasale and nose
 Shortening of upper lip
 Thinning of upper lip (approx. 2 mm)
 Widening of Alar base
 Deepening of supratip depression if ANS left intact
 Progressive increase in horizontal soft tissue displacement
seen from tip of nose to free end of upper lip
 Decrease in NL angle
Maxillary Advancement
 Carlotti et. al. – determined that the ratio of horizontal
change of upper incision to vermillion border of the upper
lip with use of the alar cinch suture and the VY closure
 The ratio reduces with larger advancements due to soft tissue
stretching: 0.6:1 vs. 0.9:1
 Maxillary Advancement
Maxillary Impaction – superior
 Elevation of nasal tip
 Widening of alar base (2-4 mm)
 Decrease in NL angle
 Nasal changes occur w/o changes in angulation of upper lip
 Lip follows superiorly approx 40% of the vertical maxillary
plane
 Lip shortening accentuated with combined anterior/superior
max movements
 If no VY – amnt of vertical soft tissue change increases
progressively from nasal lip to stomion with loss of
vermillion
 Maxillary Impaction
Maxillary inferior repositioning
 Loss of nasal tip support
 Downward repositioning of the columella and alar bases
 Thinning of the lip
 Increase NL angle
Maxillary posterior repositioning
 Loss of nasal tip support
- due to movement of ANS
- movement of bony area around piriform aperture
 Lip rotation
 Posterior and superiorly about SubNasale
 Increased NL angle
 Maxillary Setback
Multi-direction Maxillary movements
Mandibular surgical procedures
 Generally soft tissues follow hard tissues closely
 Exception is lower lip
 Types of movements
 Anterior
 Posterior
 Anterior segmental
 Autorotation
 Genial Segmental procedures
Mandibular surgical procedures anterior
 Mandibular Advancement
 Limited to the structures below the superior labial sulcus
 Little change in the upper lip and none above the ANS
 Lower lip advancement is variable and lip often lengthens
 Lower labial sulcus and chin adhere to the bony structure and
follow underlying osseous structures
 Leads to opening of labio-mental fold
Mandibular surgical procedures anterior
 Mandibular Advancement
 Facial Height
 In high angle II cases – results in large increase in FH
 Lower lip position
 Affected by upper, lower incision and its contact with the upper lip
 In class II – lower lip may touch the upper lip/incisor and fold forward –
correction of this is necessary to approximate true post-op position
 Mandibular
advancement
Mandibular surgical procedures Posterior
 Mandibular Setback
 No net effects on subnasale or tissues superior to it
 Soft tissues follow mandible posteiorly
 Chin most closely
 Lower lip
 Shortens
 More protrusive and curls out
 Labiomental fold deepens + becomes more acute
Mandibular Setback
Mandibular surgical procedures
 Anterior Segmental Osteotomy
Mandibular Surgical Procedures -autorotation
 Soft tissues follow the osseous landmarks approx 1:1
 Except lower lip – falls slightly lingual to the arc of rotation
Mandibular Surgical Procedures -Genioplasty
 Anterior
Mandibular Surgical Procedures -Genioplasty
 Posterior -- setback
Mandibular Surgical procedures –
Vertical Augmentation/reduction Genio
 Soft tissues follow hard tissues very closely in augmentation
genio compared to reduction
Controlling Soft Tissue
 Poor Surgical Results
 Surgical Techniques
 VY closure
 Cinch Suturing
 Figure 8 technique
 Dual alar cinch suture
 Contouring ANS
 Double VY closure
 Bilateral alar base wedge resection
 Septoplasty
 Advancement genioplasty / liposuction – excess submental
adipose tissue and/or short cervicomental distance
Controlling Soft Tissue
Controlling Soft Tissue
Controlling Soft Tissue
 VY closure
Controlling Soft Tissue
 Cinch Suture – figure 8
Controlling Soft Tissue
 Dual Alar cinch Suture
Controlling Soft Tissue
 Contouring of ANS
Controlling Soft Tissue
 Double VY
Controlling Soft Tissue
 Bilateral Alar Base wedge
resection
Controlling Soft Tissue
 Septoplasty
 Cartilagenous septum – should be reduced during maxillary
impactions of > 3 mm to prevent post-op deviation
 Avoid over reduction – as it can cause saddle nose deformity or
poly-beak deformity