Key points

Minimally invasive (MI) surgery has been described by Hunter as “a discipline that involves operative procedures in ‘a novel way’ to diminish the sequelae of standard surgical care.” A systematic review of the literature reveals evidence that patients undergoing orthognathic surgery using small incisions and minimal dissection have less morbidity and make a faster postsurgical recovery. This evidence has been shown regarding Le Fort I surgical transversal expansion, Le Fort I, ^{, ,} sagittal split, and chin osteotomies in the literature. The purpose of this article is to present a novel surgical algorithm to increase surgical efficiency and minimize patient morbidity by introducing surgical codes for each instrument and dedicated surgical sequences that identify each procedure. “Step-by-step” MI surgical techniques are presented for the 5 main surgical orthognathic procedures, based on their individual surgical sequences and codes.

Minimally invasive standardized surgical orthognathic techniques using surgical codes and sequences

To allow standardization, sequence templates were developed that indicate the systematic order of the coded instruments in regard to the surgical orthognathic procedure (L1 MI Orthognathics; KLS Martin, Tuttlingen, Germany) ( Fig. 1 ). The different surgical sequences based on the surgical codes are outlined in Box 1 for the following 5 main orthognathic surgical procedures:

• 1.

  MI Le Fort I osteotomy ( Figs. 2–4 )

  

  Minimally invasive (MI) Le Fort I surgical procedure: step 1 to step 5.

  

  MI Le Fort I surgical procedure: step 6 to step 9.

  

  MI Le Fort I surgical procedure: step 9 (continued) to step 10.

• 2.

  MI sagittal split osteotomy ( Figs. 5 and 6 )

  

  MI sagittal split osteotomy procedure: step 1 to step 6.

  

  MI sagittal split osteotomy surgical procedure: step 7 to step 10.

• 3.

  MI chin osteotomy ( Figs. 7 and 8 )

  

  MI chin osteotomy surgical procedure: step 1 to step 5.

  

  MI chin osteotomy surgical procedure: step 6 to step 10.

• 4.

  MI maxillary expansion ( Figs. 9–12 )

  

  MI Le Fort I expansion surgical procedure: step 1 to step 2.

  

  MI Le Fort I expansion surgical procedure: step 2 to step 3.

  

  MI Le Fort I expansion surgical procedure: step 4 to step 6.

  

  MI Le Fort I expansion surgical procedure: step 7 to step 10. f: (Rapid Palatal Expander (RPE), KLS Martin, Tuttlingen, Germany).

• 5.

  MI mandible constriction/expansion ( Fig. 13 )

  

  MI mandible constriction/expansion surgical procedure: step 1 to step 5.

Surgical instruments to perform a minimally invasive (MI) Le Fort I and bilateral sagittal split osteotomy are placed in a standardized and systemized manner on the operating table using surgical codes and sequence templates that determine the surgical sequence of the orthognathic surgical procedure (L1® MI Orthognathics, KLS Martin, Tuttlingen, Germany.)

The operating surgeon is positioned in front of the head of the patient while 2 surgical assistants are positioned at each side to perform an MI Le Fort I, MI chin, MI maxillary expansion, and MI mandible narrowing or expansion procedure. In the case of an MI sagittal split osteotomy, the operating surgeon is positioned at the right (or left) side of the head of the patient while 1 surgical assistant is positioned at the side and the other at the patient’s head.

The MI Le Fort I, MI sagittal split, and MI chin orthognathic surgical procedures are illustrated on an edentulous human cadaver with an upper and lower jaw prosthesis (see Figs. 2–8 ), and the MI maxillary expansion and MI mandible narrowing/expansion orthognathic procedures are shown on another human cadaver (see Figs. 9–13 ).

Minimally invasive Le Fort I osteotomy

A 10-step surgical technique is used to perform an MI Le Fort I osteotomy (nonsegmental or segmental). The surgical codes and sequence for the MI Le Fort I osteotomy are outlined in Box 1 and illustrated by cadaver surgical photos in Figs. 2–4 .

• •

  (Step 1) MI soft-tissue approach to the Le Fort I osteotomy

• •

  (Step 2) MI subperiosteal dissection of the medial pillar of the maxilla

• •

  (Step 3) Marking landmarks for vertical repositioning of the maxilla

• •

  (Step 4) Degloving of the nasal floor and septum release

• •

  (Step 5) MI exposure of the maxilla by subperiosteal tunneling

• •

  (Step 6) MI Le Fort I corticotomy

• •

  (Step 7) MI osteotomy of the medial and lateral maxillary pillars

• •

  (Step 8) MI downfracture and pterygomaxillary (PTM) dysjunction followed by mobilization of the osteotomized maxilla

• •

  (Step 9) Remodeling of the nasal floor and nasal septum, and removal of potential premature bone contacts

• •

  (Step 10) MI repositioning and fixation of the maxilla in its 3-dimensional (3D) virtual planned position

The MI approach toward a Le Fort I osteotomy starts (step 1) by gently placing a soft-tissue double hook (HK1) by the operating surgeon in the midline of the mucosa of the upper lip close to its border (see Fig. 2 A). Two small curved soft-tissue retractors (RT1 ×2) are placed simultaneously by the two surgical assistants to retract the soft tissues of the upper lip (see Fig. 2 A). A mucosal incision is made from lateral incisor to lateral incisor using a #15 scalpel or a Colorado needle followed by an incision of the deep layers through the periosteum at the Le Fort I level, allowing a good muscle bulk for paranasal cross-suturing of the nasolabial muscles. Strict subperiosteal degloving is performed (step 2) using the large part of the double-sided sharp raspatorium (MI1) along the right lateral nasal wall. Consecutively, the inner part of the lateral nasal wall is degloved initially using the small part of the double-sided sharp raspatorium (MI1) and then with its larger part (see Fig. 2 B). The same procedure is subsequently performed on the left side. The soft tissues are protected by the surgical assistants using a blunt double-sided elevator (MI2) and a double retractor (Mx1), while the operating surgeon marks landmarks (step 3) bilaterally at the medial pillar of the maxilla using a caliper (BI1) and a thin (1 mm) fissure burr (see Fig. 2 C). Strict subperiosteal degloving of the nasal floor (step 4) is performed using the large part of the double-sided sharp raspatorium (MI1) by the surgeon followed by the septum release under finger control at the posterior palate using a septum osteotome (OS1) and a mallet (BI-TAP) (see Fig. 2 D). A subperiosteal tunnel is made (step 5) using a sharp raspatorium (MI1) in the direction of the infrazygomatic crest (see Fig. 2 E), where a curved soft-tissue retractor for the right side (Mx2R) is placed by the surgeon (see Fig. 2 F). A thin malleable soft-tissue retractor (Mx3) is placed subsequently on the inner side of the lateral nasal wall to protect the soft tissues (see Fig. 2 F). An additional small soft-tissue retractor (RT1) is positioned at the lateral nasal wall and held by a surgical assistant (see Fig. 2 F). The surgeon performs the Le Fort I corticotomy (step 6) in the subperiosteal tunnel on the right (or left) side with an oscillating saw while the soft tissues and infraorbital nerves are protected with soft-tissue retractors (Mx2R or Mx2L, RT1, and Mx3) (see Fig. 3 A). The medial and lateral walls of the maxilla are osteotomized (step 7) to the level of the pterygoid plate with a straight osteotome (OS2) on the medial wall (see Fig. 3 B) and an angled osteotome (OS3) on the lateral wall (see Fig. 3 C). The soft tissues are meanwhile protected by the surgical assistant with soft-tissue retractors (Mx2R or Mx2L and Mx3). The same procedure is performed on the left (or right) side. The osteotomized maxilla is anteriorly mobilized (step 8) using a sharp 8-mm osteotome (OS6) on the left (or right) nasal wall while a short thin bone spreader (Mx4S) is inserted at the level of the Le Fort I corticotomy on the right (or left) nasal wall (see Fig. 3 D). It is crucial to downfracture the maxilla anteriorly only for approximately 8 mm to avoid a transverse fracture in the posterior maxilla. The PTM dysjunction is performed by inserting a long thin bone spreader (Mx4L) at the level of the Le Fort I corticotomy on the ipsilateral infrazygomatic crest (see Fig. 3 E). A vertical movement is performed to open the bone spreader (Mx4L) to dysjunct the PTM suture followed by a clockwise rotation of the spreader to mobilize the osteotomized maxilla. The same procedure is now performed at the contralateral side. After mobilization, the osteotomized maxilla is gently pulled downward with a blunt hook (HK2) by the surgical assistant (see Fig. 3 F). The bony septum is removed (step 9) using septum scissors (Mx5) while the soft tissues are protected by the surgical assistant using the double retractor (Mx1) (see Fig. 3 F). The septum scissors (Mx5) can also be used if further reduction of the cartilage septum is required. Additional removal of premature bone contacts and remodeling of the nasal floor can be performed with a burr (see Fig. 4 A) while the soft tissues are protected by the surgical assistant using the double retractor (Mx1) and a blunt double-sided elevator (MI2). Segmentation of the maxilla can now be carried out if required. The maxilla is repositioned and fixed (step 10) in its 3D virtual planned position with two L-plates on the lateral nasal wall (see Fig. 4 B–D) or a patient-specific implant (MI-PSI) in the case of splintless transfer with an MI surgical guide. During osteosynthesis fixation, vertical repositioning of the osteotomized maxilla can be controlled by a caliper (BI1) (see Fig. 4 C) or control instrument (BI2). After gentle placement of a curved soft-tissue retractor (Mx2R/Mx2L) and a small curved soft-tissue retractor (RT1), additional straight plates with a tap can be placed by the operating surgeon using a clamp (BI3) at the lateral pillar (see Fig. 4 E, F). Finally, double-layer closure with paranasal cross-suturing of the nasolabial muscles using Vicryl 3.0 (Ethicon, Johnson and Johnson, Somerville, NJ, USA) and mucosa using Vicryl 4.0 Rapide (Ethicon) is performed while the soft tissues are gently held by the surgical assistants with 2 small curved soft-tissue retractors (RT1 ×2) and two single soft-tissue hooks (HK3 ×2).

Minimally invasive sagittal split osteotomy

A 10-step surgical technique is routinely used clinically to perform an MI sagittal split osteotomy. The surgical codes and sequence regarding the MI sagittal split osteotomy are outlined in Box 1 and illustrated by cadaver surgical photos in Figs. 5 and 6 .

• •

  (Step 1) MI soft-tissue approach to the sagittal split osteotomy of the mandible

• •

  (Step 2) MI access toward the buccal corticotomy of the horizontal mandibular ramus

• •

  (Step 3) MI buccal corticotomy of the horizontal mandibular ramus

• •

  (Step 4) MI retromolar degloving

• •

  (Step 5) MI access toward the lingual corticotomy of the vertical mandibular ramus

• •

  (Step 6) MI lingual corticotomy of the vertical mandibular ramus

• •

  (Step 7) MI completion of the sagittal split osteotomy

• •

  (Step 8) MI mobilization of the mandibular segments after sagittal split osteotomy

• •

  (Step 9) “Trivector seating” of the mandibular proximal segment

• •

  (Step 10) MI rigid fixation of the sagittal split osteotomy

The MI approach toward a sagittal split osteotomy starts (step 1) by gently placing small (RT1) and large (RT2) soft-tissue retractors by the surgical assistants to retract the soft tissues of the lower jaw (see Fig. 5 A). Using a #15 scalpel, the surgeon starts the mucosal incision at approximately 1 cm behind the second molar. The incision then continues perpendicular on the bone until the distal level of the first lower molar. Using a sharp raspatorium (MI1), a subperiosteal tunnel is created (step 2) by a sliding movement toward the antegonial notch (see Fig. 5 B). The surgeon retracts the soft tissues with a blunt elevator (MI2) and inserts a small-channel retractor (Md1) following a strict subperiosteal path toward the antegonial notch (see Fig. 5 C). A buccal corticotomy is subsequently performed with a Lindemann burr or a saw (step 3). Using a V-shaped elevator (MI4), the soft tissues are elevated (step 4) on the vertical mandibular ramus until the insertion of the temporalis muscle (see Fig. 5 D). After retromolar degloving, a ramus hook (Md2) is placed by the surgical assistant. While gently retracting the soft tissues lingually using a blunt elevator (MI2), the surgeon creates a subperiosteal tunnel (step 5) by a sliding movement using a sharp raspatorium (MI1) above the lingula (see Fig. 5 E). A second small-channel retractor (Md1) is now inserted just above the lingula following a strict subperiosteal path to protect the inferior alveolar nerve. Following this, a lingual corticotomy is performed (step 6) with a Lindemann burr or saw behind the lingula or to the posterior border of the vertical mandibular ramus (see Fig. 5 F). The surgeon now connects (step 7) the lingual and buccal corticotomy along the buccal cortex with a short Lindemann burr (see Fig. 6 A) or saw. Using a thin osteotome (OS4), the lingual osteotomy is initiated behind the lingula (see Fig. 6 B) followed by completion of the sagittal split osteotomy with a wedge osteotome (OS5) and a mallet (BI-TAP), while the mandibular lower border is supported by the surgical assistant using a small-channel retractor (Md1) and the hand (see Fig. 6 C). The proximal mandibular segment is now further released and mobilized (step 8) using a wedge osteotome (OS5) in combination with an 8-mm sharp osteotome (OS6) (see Fig. 6 D). The proximal segment is seated using the “trivector seating” technique (see below) (step 9) in centric relation using a V-shaped elevator (MI4) and a bone-holding forceps (Md3) (see Fig. 6 E). To avoid torque on the condyle, an appropriate MI spacer (Md4-9) can be placed in between the proximal and distal mandibular fragments if needed (see Fig. 6 E). The proximal and distal mandibular fragments are then fixed (step 10) in their planned position using bicortical screws (see Fig. 6 F), mini-plate osteosynthesis, or a combination. Finally, one-layer closure of the wound is performed with Vicryl 3.0 (Ethicon) and fibrin glue (Tisseel; Baxter, Deerfield, IL, USA) is applied in the wound.

Minimally invasive chin osteotomy

A 10-step surgical technique is used to perform an MI chin osteotomy. The surgical codes and sequence for the MI chin osteotomy are outlined in Box 1 and illustrated by cadaver surgical photos in Figs. 7 and 8 .

• •

  (Step 1) MI soft-tissue approach to the chin

• •

  (Step 2) MI access to the bony chin

• •

  (Step 3) MI exposure of the bony chin

• •

  (Step 4) Marking the skeletal chin midline toward the lower dental midline

• •

  (Step 5) Marking a horizontal reference line in the midline

• •

  (Step 6) MI exposure of the unilateral bony chin by subperiosteal tunneling

• •

  (Step 7) MI chin osteotomy

• •

  (Step 8) Completion of the MI chin osteotomy

• •

  (Step 9) MI mobilization of the bony chin after osteotomy

• •

  (Step 10) MI repositioning and rigid fixation of the chin in its 3D virtual planned position

The MI approach for a chin osteotomy (step 1) starts by gently placing a soft-tissue double hook (HK1) in the midline of the mucosa of the lower lip close to its border. Consecutively, 2 small curved soft-tissue retractors (RT1 ×2) are placed in a symmetric way by the 2 surgical assistants to retract the soft tissues of the lower lip (see Fig. 7 A). A mucosal incision is made using a #15 scalpel high in the mucosa of the lower lip (see Fig. 7 B) along its outer contour, followed by a gentle submucosal dissection of a vestibular mucosal flap while identifying the mentalis muscles (step 2). Consecutively, the deep layers are incised through the periosteum on the chin bone using a #15 scalpel, approximately 5 mm below the mucosal incision, allowing good muscle bulk for a double-layer closure of the wound. Strict subperiosteal degloving (step 3) is now performed in the chin midline using a sharp raspatorium (MI1) by the surgeon while supporting the chin with the other hand (see Fig. 7 C). Subperiosteal degloving is performed by a sliding movement toward the chin symphysis. A chin retractor (Ch1) is inserted at the mandibular symphyseal border by following a strict subperiosteal path (see Fig. 7 D). Using a 1-mm fissure burr, the skeletal chin midline is marked (step 4) toward the lower dental midline while the soft tissues are protected using a raspatorium (MI1) and 2 small soft-tissue retractors (RT2 ×2) by the surgical assistants placed in a symmetric way (see Fig. 7 E). The bony chin is meanwhile supported by the chin retractor (Ch1) held by one of the surgical assistants. Using a 1-mm fissure burr, the central horizontal part of the chin osteotomy (mostly slightly inclined) is marked (step 5) by the surgeon (see Fig. 7 F). One surgical assistant is meanwhile supporting the bony chin with the chin retractor (Ch1) and protecting the soft tissues on the right side with a small soft-tissue retractor (RT1), while the other surgical assistant is protecting the soft tissues at the left side using another small soft-tissue retractor (RT1). Once the surgeon has made a subperiosteal tunnel (step 6) with a raspatorium (MI1) below the right (or left) mental foramen, a twisted elevator (MI3) is placed in the subperiosteal tunnel at the mandibular border (see Fig. 8 A) and an ipsilateral chin corticotomy (see Fig. 8 B) is made using an oscillating saw (step 7) according to the 3D virtual plan, while protecting both the mental nerves and the soft tissues at the mandibular lower border with the twisted elevator (MI3). The surgical assistants are meanwhile supporting the chin with the chin retractor (Ch1) and protecting the soft tissues at the left (or right) side with a small soft-tissue retractor (RT1). The same steps are performed on the contralateral side. Using a wedge osteotome (OS5) and a mallet (BI-TAP), the chin osteotomy is now completed (step 8) by the operating surgeon while the chin is supported by the chin retractor (Ch1) held by one of the surgical assistants (see Fig. 8 C). The osteotomized chin can now be further mobilized (step 9) if necessary by using an 8-mm sharp osteotome (OS6) (see Fig. 8 D). The chin is consequently repositioned and fixed (step 10) in its 3D virtual planned position using a prebent osteosynthesis plate held by the surgeon using a clamp (BI3) (see Fig. 8 E, F). Finally, double-layer closure of the wound is performed by approaching the mentalis muscles using Vicryl 3.0 (Ethicon) and the mucosa using Vicryl 4.0 Rapide (Ethicon) while the soft tissues are gently held by the surgical assistants with 2 small curved soft-tissue retractors (RT1 ×2).

Minimally invasive Le Fort I expansion

A 10-step surgical technique is used to perform an MI Le Fort I transversal expansion. The surgical codes and sequence regarding MI Le Fort I Expansion are outlined in Box 1 and illustrated by cadaver surgical photos in Figs. 9–12 .

• •

  (Step 1) MI endonasal approach to the Le Fort I corticotomy

• •

  (Step 2) MI exposure of the hemimaxilla by subperiosteal tunneling

• •

  (Step 3) MI subperiosteal dissection of the inner part of the lateral nasal wall

• •

  (Step 4) MI Le Fort I corticotomy

• •

  (Step 5) MI osteotomy of the medial and lateral maxillary pillars

• •

  (Step 6) MI intraoral approach toward the midline Le Fort I osteotomy

• •

  (Step 7) Marking the skeletal maxillary midline toward the upper dental midline

• •

  (Step 8) MI maxillary midline osteotomy and mobilization

• •

  (Step 9) MI PTM disjunction/septum release if required

• •

  (Step 10) Placement and/or activation of a maxillary expansion apparatus (bone-borne, teeth-borne, or hybrid teeth-bone–borne)

The MI approach toward a Le Fort I expansion starts endonasally (step 1) by gently placing a short nasal speculum (NS) in the right nostril (see Fig. 9 A, B) as an access to the soft tissues on the medial pillar of the maxilla (see Fig. 9 C). A 5-mm incision is made using a #15 scalpel in the region of the lateral nasal wall through the mucosa and periosteum on the bone at the Le Fort I level parallel with the upper occlusal plane (see Fig. 9 D). Strictly subperiosteal degloving is now performed (step 2) initially using the small part (see Fig. 9 E) and consequently the large part (see Fig. 9 F) of the double-sided sharp raspatorium (MI1) along the lateral nasal wall. A subperiosteal tunnel is made using the large part of the double-sided raspatorium (MI1) in the direction of the infrazygomatic crest (see Fig. 10 A). The tunnel is then kept open by the surgeon with a curved blunt raspatorium (MI2) (see Fig. 10 B) to insert a curved soft-tissue retractor (Mx2R) (see Fig. 10 C). Following this, (step 3) a small soft-tissue retractor (RT3) is placed (see Fig. 10 D) by the surgical assistant at the medial side of the right nostril and the inner part of the right lateral nasal wall is degloved using the small part of the double-sided sharp raspatorium (MI1), while retracting the nasal soft tissues with a curved blunt raspatorium (MI2) (see Fig. 10 E). A thin malleable soft-tissue retractor (Mx3) is placed at the inner side of the lateral nasal wall to protect the soft tissues (see Fig. 10 F). The surgeon performs the Le Fort I corticotomy (step 4) in the subperiosteal tunnel on the right side with an oscillating saw while the soft tissues and infraorbital nerve are protected with soft-tissue retractors (Mx2R or Mx2L for the left side, and Mx3) (see Fig. 11 A, B). The medial and lateral walls of the maxilla are respectively ipsilaterally osteotomized (step 5) toward the pterygoid plate, with a straight osteotome (OS2) on the medial wall (see Fig. 11 C) and an angled osteotome (OS3) on the lateral wall (see Fig. 11 D). The same procedure is performed on the other side. The MI approach toward Le Fort I Expansion continues intraorally. Two small soft-tissue retractors (RT3 ×2) are placed by the 2 surgical assistants to retract the soft tissues in the midline in the upper vestibule. A small, vertical midline incision is made (step 6) using a #15 scalpel through the mucosa and periosteum (see Fig. 11 E) to have access to the maxillary midline (see Fig. 11 F). Strictly limited subperiosteal degloving is performed in the maxillary midline region using the small part of the double-sided sharp raspatorium (MI1) (see Fig. 12 A) by the surgeon. Two small soft-tissue retractors (RT3 ×2) are placed in the subperiosteal plane. In most of the cases, the skeletal maxillary midline (step 7) can easily be identified at the level of the midline maxillary suture by the small part of the double-sided sharp raspatorium (MI1), and no burrs or piezosurgery are necessary (see Fig. 12 B). Using a thin osteotome (OS4) (see Fig. 12 C) and a mallet (BI-TAP), the midline maxillary osteotomy (step 8) is anteriorly initiated under finger control by the operating surgeon and further completed posteriorly as a green-stick fracture. Mobilization of both hemimaxillae is performed and controlled using an 8-mm sharp osteotome (OS6) (see Fig. 12 D). Only when posterior maxillary widening is required, the PTM sutures are weakened transmucosally by the surgeon using a 10-mm curved osteotome (OS7) while the cheek soft tissues are retracted using a large soft-tissue retractor (RT2) by the surgical assistant (see Fig. 12 E). Septum release is performed when a unilateral expansion is required. Finally, the maxillary bony expansion apparatus is placed (see Fig. 12 F) and activated. When a tooth-borne distraction apparatus is used, it should be placed before the surgery by the orthodontist, and weakening of the pterygomaxillary sutures is always performed as already described. One-layer closure of the intraoral and endonasal mucosa is performed using Vicryl 5.0 Rapide (Ethicon) while the soft tissues are gently held by the surgical assistants using small soft-tissue retractors (RT3).

Minimally invasive mandible narrowing/expansion

A 5-step surgical technique is used to perform an MI mandibular midline osteotomy for narrowing or expansion. The surgical codes and sequence regarding the MI mandibular midline osteotomy are listed in Box 1 and illustrated by cadaver surgical photos in Fig. 13 .

• •

  (step 1) MI soft-tissue approach to the chin

• •

  (step 2) MI access and exposure of the bony chin

• •

  (step 3) Marking the skeletal chin midline toward the lower dental midline

• •

  (step 4) MI chin midline osteotomy and mobilization

• •

  (step 5) MI repositioning and rigid fixation of the chin in its 3D virtual planned position or placement of a mandibular transverse expansion device (teeth-borne, bone-borne, or hybrid teeth-bone–borne).

The MI approach for a mandibular midline osteotomy (step 1) for mandibular midline narrowing or expansion starts by gently placing a soft-tissue double hook (HK1) by the surgeon in the midline of the mucosa of the lower lip close to its border. Following this, 2 small curved soft-tissue retractors (RT1 2×) are placed by the 2 surgical assistants to retract the soft tissues of the lower lip. A small vertical midline incision is made (step 2) using a #15 scalpel through the mucosa and the deep layers to access the bony chin (see Fig. 13 A). Strictly limited subperiosteal degloving is now performed in the chin midline region using a sharp raspatorium (MI1) by the operating surgeon while supporting the chin with the other hand. Two small soft-tissue retractors (RT3 ×2) are placed by the 2 surgical assistants to retract the soft tissues (see Fig. 13 B). Using a 1-mm fissure burr (or piezosurgery), the skeletal chin midline is marked (step 3) toward the lower dental midline (see Fig. 13 C, D). Using a thin osteotome (OS4) and a mallet (BI-TAP), the chin midline osteotomy is now initiated, completed, and further mobilized using an 8-mm sharp osteotome (OS6) (step 4) by the surgeon (see Fig. 13 E). As an alternative, the midline chin osteotomy can be performed by piezosurgery. After removal of bony interference, the chin is repositioned and fixed (step 5) in its 3D virtual planned position using an osteosynthesis plate in the case of mandibular narrowing (see Fig. 13 F), or a mandibular transverse expansion device is placed. Finally, double-layer closure of the wound is performed using Vicryl 4.0 and Vicryl 5.0 Rapide (Ethicon) while the soft tissues are gently held by the surgical assistants with 2 small curved soft-tissue retractors (RT1 ×2).

The clinical relevance of introducing surgical codes and sequences in orthognathic surgery

In 2014, the author published a “10 step-by-step” protocol toward integrating computer-aided 3D virtual planning of orthognathic surgery in daily clinical routine in a user-friendly way. Its further optimization significantly decreased overall virtual treatment planning time in the author’s daily clinical orthognathic practice. In decreasing surgical morbidity of patients, one of the main parameters is the duration of the operating time, besides other factors such as hypotensive anesthesia, medication and dietary management, manual lymph drainage, and application of cooling masks. Computer-aided 3D virtual treatment planning allows one not only to decrease the operating time but also to perform MI orthognathic surgical procedures through smaller incisions with less degloving because virtual surgery is already performed before the actual surgical intervention. Additional devices such as endoscopy and piezosurgery can also be helpful for the latter goal.

According to Hunter’s philosophy, standard orthognathic surgical procedures are presented in this article in a novel way by introducing surgical codes and sequences in an attempt to further decrease the operating time. The use of coded instruments and surgical sequence templates has the potential to optimize overall surgical efficiency: (1) it allows the scrub nurse to organize the surgical instruments in a more systemized manner and to better anticipate the surgeon especially in settings whereby orthognathic surgery is not a daily clinical routine; (2) it also allows inexperienced surgical assistants to become more efficient because of the “step-by-step” systematization of each aspect of the orthognathic surgical procedure; and (3) the coding of surgical instruments allows standardized storage, which facilitates sterilization and better guarantees protection against potential loss or absence of any instrument in the surgical set. Last but not least, standardization by surgical codes and sequences can be cost-efficient through decreasing overall operating time and improving logistics.

Summary

Standardizing each individual step of orthognathic surgical procedures with the use of surgical codes and sequences has the potential to increase overall surgical efficiency of the orthognathic team and to decrease patients’ surgical morbidity and costs.