We have observed a revival of the original Surgery First approach in orthognathic surgery. Fully digital planning and simulation of the surgery has improved the predictability of Surgery First procedures. The orthodontist plays a crucial role in the successful management of Surgery First and Surgery Early cases. Surgery First and Surgery Early procedures have made the correction of a dentofacial deformity and dysgnathia a clear and transparent procedure. The decision of the treatment protocol is based on a thorough consideration and discussion between the surgeon, the orthodontist, and the patient for a successful outcome.
Key points
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Surgery First approach or Surgery Early approach should be included in the consideration of orthognathic surgery planning with the input from both the surgeon and the orthodontist.
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Surgery First approach allows an immediate correction of the skeletal discrepancies of the patients and shortens the overall treatment time.
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Surgery Early approach may help to eliminate some unfavorable factors of Surgery First approach, such as postoperative instability or occlusal disharmony (eg, insufficient overbite, such as compromised inter-canine width).
Historical background
At the beginning of orthognathic surgery in the 1960s, surgeons, independent of their background, whether plastic or oral maxillofacial surgeons, were forced to do the Surgery First approach when they wanted to correct a skeletal deformity because there was no efficient orthodontic treatment available at that time. The goal of the treatment plan was mainly driven by correcting the skeletal deformity, harmonizing the skeleton, and achieving the best possible jaw relation, but accepting minor discrepancies of the Angle classes, misalignments, or crossbites of the dental arches. The consequence was a deficit of perfect functional rehabilitation and in the long term, a lack of predictability and stability of the achieved surgical results.
It was in the 1980s with William Bell , that a paradigm shift in orthognathic surgery was introduced. With the rapid development of orthodontic appliances and improvement of techniques, it became obvious that any preoperative removal of dental obstacles in the occlusion was advantageous for the surgeon in two ways. A stable interdigitation was created in the preoperative setup, according to the aligned dental arches, which signaled stability of the postoperative results, and the final occlusion became the center of imagination and the face was built around by osteotomizing the jaws. In fact, this is a perfect concept for the surgeon, the orthodontist, and the patient.
Introduction
The concept of preoperative orthodontics followed by surgery, called the Orthodontics First approach, was the state-of-the-art for nearly half a century and still is routinely done, especially in the Anglo-American and the Western world.
As described by J.W. Choi in his book titled, The Surgery–First Orthognathic Approach in 2002, a new treatment protocol was published by a Korean study group in the Korean Journal of Clinical Orthodontics on a new treatment concept called “Functional Orthognathic Surgery.” There are some controversies on the founders of the Surgery First approach because of different definitions of the approach, and mode of concomitant orthodontic treatment pre-op or primarily post-op. The new concept of orthognathic surgery was well and fast taken and put in place especially in Korea, Japan and, Taiwan with minor individualizations.
Societies change, and lifestyles and expectations of our patients change, too. Esthetic improvements have moved to the foreground and visible results are expected within a short time. Especially in the Asian world, this was strongly boosted by the mass media but because we are living in a global environment with online connections, this trend was quickly picked up internationally. And action provokes a reaction, especially in the western hemisphere any preoperative orthodontic treatment was expanded up to two years which created an unacceptable and unfavorable overall long treatment time for the patients.
Any Surgery First or Surgery Early treatment approach includes the advantage of reduced treatment time. We know from the previous publications that in the conventional Orthodontics First approach, the preoperative treatment time is prolonged and that the overall treatment period in bimaxillary cases can last about 18–28 months. In contrast, in the Surgery First approach, the overall treatment time is reduced to about 38 weeks on average as published by Hernández-Alfaro and colleagues, which corresponds with our own observation. The difference between the two treatment options is the number of appointments with the orthodontists. In the Surgery First approach cases that require extractions combined with maxillary segmentations, the postoperative orthodontic treatment times may be slightly prolonged when compared to single-piece nonextraction cases.
The advantage of surgery first
There is an additional reason why the Surgery First protocol was well taken in the Asian region. The predominant skeletal deformity in the Asian region is skeletal Class III, with protrusive mandible and retrusive maxilla. Baik and colleagues reported the percentage of Korean patients whose Class III relationship was primarily a result of mandibular prognathism (48%), which is more than twice as high as the corresponding number for American Class III surgical patients (19%), somewhat higher than in Chinese (39%), and similar to the percentage of Japanese patients (50%). In the traditional Orthodontics First concept, the orthodontist decompensates the lower incisors of the patients with Class III deformities, which is a procedure that has to be done slowly and cautiously to avoid buccal recessions. The aim of the dental alignment was to allow the surgeon to create a correct overbite/overjet by the time of the surgery. For the patient, however, especially in Skeletal Class III patients ( Fig. 1 ), this period of decompensation is extremely unfavorable functionally and esthetically, which aggravates the unpleasant profile. Surgery First approach allows immediate correction of the deformity and is executed by creating a Class II relationship with an increased overjet intraoperatively for later proclination of the incisors ( Fig. 2 ). Besides, there are observations that these exaggerated protrusive movements of the lower incisors during decompensation are prone to relapse because of the mild muscular relapse of the surgical setback of the protrusive mandible.
Questionnaire studies explored the patient’s perception of the combined orthognathic/orthodontic treatment and showed that the period of the orthodontic treatment was the most uncomfortable of the whole treatment. Therefore, shortening of orthodontics time is welcomed.
Rapid acceleratory phenomenon (RAP) is one of the explanations why the postsurgical orthodontic treatment is more effective and faster. The accelerated orthodontic movement after surgery was not new, which was demonstrated after corticotomies as described by Kole. Wilcko and colleagues also demonstrated the effect by performing corticotomies in combination with alveolar buccal augmentation in the lower frontal incisors. In a literature review, Frost further explained the RAP and the bone healing process. Le Fort I osteotomy or the sagittal split osteotomy alone can act as a booster of the RAP, which is also confirmed in an animal study by Yuan and colleagues. The increased tooth mobility and highly effective orthodontic treatment are mirrored in the increased levels of serum alkaline phosphatase and the C-terminal telopeptide of type I collagen, corresponding to the altered and stimulated bone metabolism due to surgery. By measuring the serum levels of these two predictors, the time frame of the advantage of the RAP can be estimated. This window of accelerated tooth movement is observed up to 3–4 months after surgery and therefore early postoperative start of orthodontic treatment is mandatory to take advantage of the biomechanics of bone healing. Corticotomies in the buccal area of the lower incisors can be seen not only as an attempt to stimulate the RAP, but also to ease the additional mechanical tooth movement to align the dental arches.
Attention is also brought to the permanent soft tissue resistance of lip pressure or tongue thrust and dysfunction, especially in Class III skeletal deformity and open bite cases during the preoperative orthodontic period in Orthodontics First approach. A rapid skeletal correction and harmonization of the dysfunctional situations ease any postoperative orthodontic treatment by overcoming the muscle tensions.
The Selection of Patients for Surgery First Treatment Protocol
A successful outcome of orthognathic surgery based on a Surgery First concept depends primarily on the selection of the appropriate patient as well as a suitable orthodontist partner ( Fig. 3 ). The orthodontist has to be familiar with the Surgery First concept, who is willing to take over after surgery, and capable to correct the postsurgical occlusion to finish the case. Therefore, it is of uttermost importance that the surgical treatment plan is discussed and agreed upon with the orthodontist. In general, the orthodontist comes up with a piggyback occlusal setup that is used for orientation in the surgical concept ( Fig. 4 ). There are several considerations for postoperative occlusion. First of all, it is important to consider if a stable occlusion is achievable intraoperatively without preoperative orthodontics ( Fig. 5 ). Sharma and colleagues suggested the ideal case for the Surgery First approach is a patient with well-aligned dental arches and minimal crowding. This requires no segmentation of the osteotomies, due to no transversal discrepancies and no need for extractions to flatten any exaggerated Curves of Spee. Many of these cases are patients who already had orthodontic treatment in their teens when no regard was taken for any forthcoming skeletal deformity at the time of adulthood. When they grow up, the genetically determined skeletal deformity appears and makes an additional correction of the malocclusion necessary. It is understandable that these patients who already had orthodontic therapy for years in their adolescence are not willing to start orthodontics again for the orthognathic surgery preparation at the end of growth. Many would prefer an accelerated, efficient treatment path as seen in the Surgery First approach. From a surgeon’s perspective, the surgical procedures per se are of no difference to that of a conventional Orthodontics First approach. These patients are excellent candidates as a starting point for the surgeon and the orthodontist who are inexperienced in the Surgery First approach. Another challenge of the Surgery First approach is the decision between bimaxillary and single jaw procedures. In contrast to the conventional Orthodontic First approach, Surgery First approach lacks the chance to reassess the treatment plan for a second time and has to make a correct decision at the beginning of the orthognathic treatment planning. Falter and colleagues reported a 13.5% chance that the executed treatment protocol will differ from the originally designed one, therefore any surgical planning in the Surgery First approach must be well weighted to avoid any unnecessary secondary procedures. The third group, as presented in Fig. 3 , is a cohort with extended dental and skeletal deformities, patients with severe crowding, exaggerated Curves of Spee, and/or transversal discrepancies ( Fig. 6 ). Treating these patients requires a lot more considerations in the surgical planning, with a need for more surgical expertise and experience that segmental osteotomies combined with extractions may be required because the complex surgery is needed to take over any orthodontic preoperative alignment ( Fig. 7 ). Besides, it is obligatory that the patient is fully informed about the strategy of the Surgery First approach in comparison to the prolonged and more conservative procedure of the Orthodontics First approach. A signed consent form of the patient is required, highlighting that the patient was informed about different treatment options. The explanation also has to include that the Surgery First approach is combined with the expected compliance of the patient for the postoperative frequent orthodontic appointments. Short control intervals with the surgeon and the orthodontist are essential postoperatively because teeth movements are accelerated because of the RAP ( Fig. 8 ).
