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REVIEW ARTICLE |
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Year : 2021 | Volume
: 13
| Issue : 6 | Page : 947-951 |
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Autorotation of the mandible as sequelae to maxillary intrusion: A systematic review
S Ganesh Kumar Reddy1, Hisham M Ibrahim2, Shweta Bhardwaj3, Suraj Potdar4, Akshay Kumar5, Ashish Uppal6, Heena Tiwari7
1 Department of Oral and Maxillofacial Surgery, C.K.S. Teja Institute of Dental Sciences, Tirupati, Andhra Pradesh, India 2 Department of Oral and Maxillofacial Surgery, Al Azhar Dental College, Thodupuzha, Kerala, India 3 BDS, MPH, University of Saskatchewan, Saskatoon, Canada 4 Department of Orthodontics and Dentofacial Orthopedics, Vasantdada Patil Dental College and Hospital, Kavalapur, Maharashtra, India 5 Department of Oral and Maxillofacial Surgery, Sardar Patel Post Graduate Institute of Dental and Medical Sciences, Uttar Pradesh, India 6 Department of OMFS, College of Dental Sciences, Babu Banarasi Das University, Lucknow, Uttar Pradesh, India 7 BDS, MPH Final Year Student, Parul University, Vadodara, Gujarat, India
Date of Submission | 15-May-2021 |
Date of Decision | 23-May-2021 |
Date of Acceptance | 28-May-2021 |
Date of Web Publication | 10-Nov-2021 |
Correspondence Address: Heena Tiwari Parul University, Limda, Waghodia, Vadodara, Gujarat India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jpbs.jpbs_389_21
Abstract | | |
Background: Autorotation of the mandible is a normally anticipated phenomenon following a surgical superior repositioning of the maxilla in clinical situations where patients have an excessive gummy smile. Prediction of the surgical treatment outcome following a presurgical orthodontic treatment is a critical element in the surgical treatment planning. Materials and Methods: The relevant articles were selected by hand search and electronic media (Google Scholar, PubMed, Science Direct, Medline, Embase, and Cochrane) from 1982 to 2020. All the relevant articles were properly screened, and findings were extracted from the articles. Results: It was observed that, following maxillary intrusion, mandible would eventually autorotate to take a new occlusion. Mandibular autorotation as a result of maxillary intrusion would lead to minimal shortening of the lower lip in the vertical plane. It was observed that the amount of mandibular autorotation correlates with the extent of maxillary impaction. Studies have shown that there is a passive soft-tissue response which may be attributed to the fact that no muscular detachment had been affected in the lower lip and soft-tissue chin region during the maxillary surgery. Conclusion: It is observed that there is a definite influence on the mandibular and chin positions as a result of maxillary intrusion and autorotation of the mandible. Every 1 mm of maxillary superior impaction, the chin moved 0.6 mm vertically and 0.2 mm horizontally. There is an appreciable shortening of the lower lip length.
Keywords: Autorotation, gummy smile, maxillary intrusion, vertical maxillary excess
How to cite this article: Reddy S G, Ibrahim HM, Bhardwaj S, Potdar S, Kumar A, Uppal A, Tiwari H. Autorotation of the mandible as sequelae to maxillary intrusion: A systematic review. J Pharm Bioall Sci 2021;13, Suppl S2:947-51 |
How to cite this URL: Reddy S G, Ibrahim HM, Bhardwaj S, Potdar S, Kumar A, Uppal A, Tiwari H. Autorotation of the mandible as sequelae to maxillary intrusion: A systematic review. J Pharm Bioall Sci [serial online] 2021 [cited 2022 Jun 28];13, Suppl S2:947-51. Available from: https://www.jpbsonline.org/text.asp?2021/13/6/947/330122 |
Introduction | |  |
Facial esthetics is considered to be a critical factor in human interactions.[1] Vertical maxillary excess (VME) is a clinical scenario that results due to overgrowth of the maxilla. It manifests clinically with excess exposure of the upper incisors even at rest coupled with a gummy smile.[2] The vertical excess growth of the maxilla results in a consequent rotation of the mandible in a clockwise manner. This subsequently results in the mandible being positioned retrognathically.[2] The surgical correction of the VME is usually done by the superior repositioning of the maxilla through a LeFort 1 osteotomy. This subsequently results in the rotation of the mandible anteriorly and superiorly thereby enhancing the facial profile still further.[2]
Literature reveals that surgical impaction of the maxilla aids in the correction of long-face syndrome, anterior open bite, and in obtaining a competent lip seal in addition to the correction of VME.[3],[4] The autorotation of the mandible associated with the maxillary impaction was initially advocated by Schendel et al., Bell et al., and Fish et al.[5],[6],[7] It is advocated that mandibular autorotation following a maxillary intrusion is associated with the projection of skeletal and soft tissues in the profile view and vertical shortening of the lower face in the frontal view.[3]
Materials and Methods | |  |
Literature search
The systematic literature search (displayed as a flow diagram in [Figure 1]) was initiated with Google Search the references of the DOI used in Sci-Hub. This service allowed the authors to use PubMed Central, ProQuest Dissertations and Theses, Science Citation Index Elsevier Science Direct Complete, Highwire Press, Springer Standard Collection, DOAJ Directory of Open Access Journals, Free E-Journals, Ovid Lippincott Williams and Wilkins Total Access Collection, Wiley Online Library Journals, and Cochrane Plus databases.
The heading sequence ([”Maxillary” OR “Le Fort I”] AND [”mandibular autorotation”] AND [”Advancement” OR “Retrusion” OR “Setback” OR “Impaction” OR “Intrusion” OR “Superior Repositioning” OR “Down grafting” OR “Inferior Repositioning” OR “Expansion” OR “Widening”]) was selected. Our initial search showed 2418 published articles. Since our inclusion criteria delegated only academic publications and the number of articles selected was decreased to 852. No articles were excluded by means of their language. Articles discussing nonhuman research were excluded, and 163 potential articles were found. Articles pertaining to syndromic cases, osteodistraction, or bimaxillary surgery were excluded such that only 51 articles remained. Among them, only 11 fulfilled inclusion criteria and exclusion criteria (see selection criteria). To finish the search, the authors also reviewed the references for each selected publication. Due to this, an additional 15 articles were found. However, only four of these could fulfill the inclusion and exclusion criteria. Eventually, this systematic review included a total of 15 articles.
Selection criteria
This study comprised the following inclusion criteria to hand-pick the probable articles from the existing literature. These include: (1) Only human patients; (2) a set of patients in whom only single jaw surgery was undertaken and that was maxillary intrusion; (3) the number of patients was mentioned; and (4) at least one parameter of soft-to-hard tissue ratio was measured from the data included in that paper. This study comprised the following inclusion criteria to hand-pick the probable articles from the existing literature. These include (1) nonsyndromic patients in the form of cleft lip and palate, Pierre Robin syndrome; (2) unrelated disease (i.e., oncologic or traumatic cases); (3) systematic reviews or meta-analyses; and (4) the use of distraction.
Data extraction
The following data were taken out from the full-text articles: (a) demographic data (i.e., the number of patients, age, gender, and race); (b) type of the study (i.e., follow-up period [months/years], course of analysis [prospective vs. retrospective], randomization, level of evidence, and method of analysis [i.e., lateral radiographs, cone beam]); and (c) type of surgical intervention (i.e., the type of surgery used for a certain bony movement, added orthognathic and/or facial procedures, use of bone graft, use of implants, amount of movement in mm [mm], removal of anterior nasal spine, use of an alar cinch suture, the use of VeY lip closure, subspinal osteotomy, and type of osteosynthesis).
Results | |  |
The results of the literature search reveal that maxillary intrusion which is generally known as maxillary impaction or superior repositioning of the maxilla was performed initially by Converse (1952) by posterior intrusion for the management of patients with open bite. However, it can also be performed anteriorly in clinical situations such as the long face syndrome with excessive prominence of the maxilla presenting with a gummy smile. All studies we found were mainly retrospective.
It was observed that, if an isolated maxillary intrusion was performed, the mandible would eventually autorotate to take a new occlusion. This ultimately would lead to the soft tissues to follow the hard tissues according to certain ratios. Previous studies have revealed that mandibular autorotation as a result of maxillary intrusion would lead to minimal shortening of the lower lip in the vertical plane.[8] However, few studies revealed that the lower lip actually lengthens following a mandibular autorotation as a result of maxillary intrusion.[9] Few studies have demonstrated that the amount of mandibular autorotation correlates with the extent of maxillary impaction.[10] Studies have shown that there is a passive soft-tissue response which may be attributed to the fact that no muscular detachment had been effected in the lower lip and soft-tissue chin region during the maxillary surgery [Table 1].
Discussion | |  |
Literature search reveals that a clinician evaluating the esthetics particularly on a profile photograph of an individual who underwent an orthognathic surgery emphasizes more on the lips and chin, followed by the nose.[11] This implies that an ideal anatomical positioning of lips and chin is of boundless importance.
Influence of maxillary intrusion on mandible
It is noteworthy that, in patients who have a mandibular deficiency in addition to a gummy smile, the sagittal advancement accomplished by the mandibular autorotation following a maxillary intrusion is more appreciable as it will eventually result in enhanced sagittal relationship of both the jaws.[12] A previous study revealed that an average of 5 mm maxillary impaction would lead to a 2 mm horizontal advancement and 1.2 mm vertical shortening of the chin in the postoperative phase when using the radiographic condylar center of the mandible as the rotation center of mandibular autorotation in the presurgical predictions.[13]
It is a well-known fact that the vertical dimensions of the lower face would change when the maxilla is impacted and the mandible autorotates. There exist numerous reports in the literature on the degree of decrease in lower facial height following a maxillary impaction. Numerous researchers have dealt with the query of the impact of maxillary impaction on mandibular autorotation a long way back and suggested a replication of the esthetic outcome on the lateral cephalogram. They advocated a 1:1 ratio between lower-face shortening following maxillary impaction and mandibular autorotation.[13],[14]
Maxillary impaction is generally performed to reduce the lower anterior facial height with concomitant advantages of mandibular autorotation to get the chin movement. A previous study found that the rotation center of the mandible revealed huge variations. The rotation center in this study was found lower than the radiographic condylar center.[15] It was concluded from the result of few studies that the mandible will eventually follow any changes in occlusion that arises as a result of maxillary impaction. It can be advocated that the esthetic changes in the mandibular and chin position would be little inconsistent and little predictable following maxillary intrusion.[16]
Influence of maxillary intrusion on temporomandibular joint
Literature reveals that clicks in the temporomandibular joint are more likely to be resolved following a prognathic reduction and maxillary impaction surgery than after mandibular advancement or combination maxillary and mandibular surgery.[12] It was observed that movements that would force the condylar head in a posterior or superior direction would eventually lead to an internal derangement of the joint. A previous study of condylar pathway tracing advocated a higher incidence of hypomobility following a mandibular advancement surgery but an enhanced function following a LeFort I osteotomy and mandibular reduction osteotomy.[17],[18]
It was noted that the soft-tissue changes associated with a maxillary intrusion were prominent on the nasal tip with an increase in alar base width, shortening of lip length, and concurrent with horizontal movements of the maxilla.[8] Previous studies have revealed that autorotation of the mandible results in shortening of the elevator muscles. As a result of this, neither an active or passive distracting forces can be exerted on the intruded maxilla by the mandibular musculature. Hence, it is considered that superior repositioning of the maxilla with the aid of a LeFort osteotomy is perhaps the utmost stable orthognathic surgical intervention.[19] In addition to this, the biomechanics of the jaw can be changed due to the autorotation of the mandible.
There exists a controversy pertaining to the site for center of rotation of the mandible, following superior repositioning of the maxilla. Few authors advocated the condyle to be the center for the autorotation of the mandible, while few authors advocated that mastoid process as the center of rotation.[5],[13] Wang et al. demonstrated that this center is located 2.5 mm behind and 19.6 mm below the radiographic condylar center of the mandible.[15] Another study proposed that the mandibular autorotation occurs at a point following maxillary intrusion that was similar to that occurred at preoperative mouth opening.[20]
A recent study observed that the occlusal plane angle in the mandibular autorotation group was steeper when compared to the nonautorotation group.[2] Another study advocated that the movement of maxilla in the superior direction has an effect on the repositioning of the chin in the anterior and cranial directions.[21]
Conclusion | |  |
The results of this study reveal that there is a definite influence on the mandibular and chin positions as a result of maxillary intrusion and autorotation of the mandible. It is noteworthy that every 1 mm of maxillary superior impaction, the chin moved 0.6 mm vertically and 0.2 mm horizontally. There is an appreciable shortening of the lower lip length.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | Uppada UK, Sinha R, Reddy DS, Paul D. Soft tissue changes and its stability as a sequlae to mandibular advancement. Ann Maxillofac Surg 2014;4:132-7. [Full text] |
2. | Peleg O, Mijiritsky E, Manor Y, Inchingolo F, Blinder D, Mortellaro C, et al. Predictability of mandibular autorotation after le fort I maxillary impaction in case of vertical maxillary excess. J Craniofac Surg 2019;30:1102-4. |
3. | Steinhäuser S, Richter U, Richter F, Bill J, Rudzki-Janson I. Profile changes following maxillary impaction and autorotation of the mandible. J Orofac Orthop 2008;69:31-41. |
4. | Schendel AS, Eisenfeld JH, Bell WH, Epker BN. The long face syndrome: Vertical maxillary excess. Am J Orthod 1976;70:398-408. |
5. | Schendel SA, Eisenfeld JH, Bell WH, Epker BN. Superior repositioning of the maxilla: Stability and soft tissue osseous relations. Am J Orthod 1976;70:663-74. |
6. | Bell WH, Creekmore TD, Alexander RG. Surgical Correction of the long face syndrome. Am J Orthod 1977;71:40-66. |
7. | Fish LC, Wolford LM, Epker BN. Surgical-orthodontic correction of vertical maxillary excess. Am J Orthod 1978;73:241-57. |
8. | Mansour S, Burstone C, Legan H. An evaluation of soft-tissue changes resulting from Le Fort I maxillary surgery. Am J Orthod 1983;84:37-47. |
9. | Ksiezycki-Ostoya B, McCollum AG, Becker PJ. Sagittal soft-tissue changes of the lower lip and chin associated with surgical maxillary impaction and consequent mandibular autorotation. Semin Orthod 2009;15:185-95. |
10. | Steinhauser S, Richter U, Richter F, Bill J, Rudzki-Janson I. Profilveranderungen nach € maxillarer impaktion und autorotation des Unterkiefers. J Orofac Orthop 2008;69:31-41. |
11. | Burcal RG, Laskin DM, Sperry TP. Recognition of profile change after simulated orthognathic surgery. J Oral Maxillofac Surg 1987;45:666-70. |
12. | Mote N, Malandkar A, Toshniwal NG, Mani S, Dhanjani V. Effects of LeFort I maxillary impaction surgery on surrounding structures in vertical maxillary excess patients- A review article. IOSR J Dent Med Sci 2019;18:59-65. |
13. | Nattestad A, Vedtofte P. Mandibular autorotation in orthognathic surgery: A new method of locating the centre of mandibular rotation and determining its consequence in orthognathic surgery. J Craniomaxillofac Surg 1992;20:163-70. |
14. | Fish LC, Epker BN. Surgical-orthodontic cephalometric prediction tracing. J Clin Orthod 1980;14:36-52. |
15. | Wang YC, Ko EW, Huang CS, Chen YR. The inter-relationship between mandibular autorotation and maxillary LeFort I impaction osteotomies. J Craniofac Surg 2006;17:898-904. |
16. | Abuzinada S, Alsulaimani F. Mandibular changes associated with maxillary impaction and molar intrusion. Open J Stomatol 2013;3:515-9. |
17. | Harper RP. Analysis of temporomandibular joint function after orthognathic surgery using condylar path tracings. Am J Orthod Dentofacial Orthop 1990;97:480-8. |
18. | Te Veldhuis EC, Te Veldhuis AH, Bramer WM, Wolvius EB, Koudstaal MJ. The effect of orthognathic surgery on the temporomandibular joint and oral function: A systematic review. Int J Oral Maxillofac Surg 2017;46:554-63. |
19. | Proffit WR, Phillips C, Turvey TA. Stability following superior repositioning of the maxilla by LeFort I osteotomy. Am J Orthod Dentofacial Orthop 1987;92:151-61. |
20. | Nadjami N, Mommaerts MY, Abeloos JV, De Clercq CA. Prediction of mandibular autorotation. J Oral Maxillofacial Surg 1998;56:1241-7. |
21. | Jayakumar J, Jayakumar N, John B, Antony PG. Quantitative prediction of change in chin position in le fort I impaction. J Maxillofac Oral Surg 2020;19:438-42. |
[Figure 1]
[Table 1]
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