Accepted Manuscript Segmental orthognathic surgery for Bolton discrepancy correction Rafael Correia Cavalcante, Paola Fernanda Cotait de Lucas Corso, Guilherme dos Santos Trento, Fernando Antonini, Nelson Luis Barbosa Rebellato, Delson João da Costa, Rafaela Scariot, Leandro Eduardo Klüppel PII:
S2214-5419(18)30062-2
DOI:
10.1016/j.omsc.2018.05.001
Reference:
OMSC 63
To appear in:
Oral and Maxillofacial Surgery Cases
Please cite this article as: Cavalcante RC, de Lucas Corso PFC, Trento GdS, Antonini F, Rebellato NLB, da Costa DJ, Scariot R, Klüppel LE, Segmental orthognathic surgery for Bolton discrepancy correction, Oral and Maxillofacial Surgery Cases (2018), doi: 10.1016/j.omsc.2018.05.001. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT SEGMENTAL ORTHOGNATHIC SURGERY FOR BOLTON DISCREPANCY CORRECTION Rafael Correia CAVALCANTE1, Paola Fernanda Cotait de Lucas CORSO1, Guilherme dos Santos TRENTO1, Fernando ANTONINI2, Nelson Luis Barbosa REBELLATO3, Delson João da COSTA3 , Rafaela SCARIOT4 , Leandro Eduardo KLÜPPEL3 . Resident in Oral and Maxillo-Facial Surgery at Federal University of Parana, Curitiba, Brazil 2 PhD Student in Oral and Maxillo-Facial Surgery at Pontific Catholic University of Rio Grande do Sul, Porto Alegre, Brazil 3 Professor of Oral and Maxillo-Facial Surgery Department of Federal University of Paraná, Curitiba, Brazil 4 Professor of Oral and Maxillo-Facial Surgery Department of Positivo University, Curitiba, Paraná, Brazil
AC C
EP
M AN U
TE
D
Corresponding author Rafael Correia Cavalcante 623th Mayor Lothario Meissner Curitiba – Paraná – Brazil Phone: +55 41 3360-4020 e-mail:
[email protected]
SC
RI PT
1
ACCEPTED MANUSCRIPT SEGMENTAL ORTHOGNATHIC SURGERY FOR BOLTON DISCREPANCY CORRECTION
M AN U
SC
RI PT
Abstract: In association with orthodontic treatment, orthognathic surgery can solve different types of malocclusion amongst dentofacial deformities. Bolton analysis is frequently used to measure the mesiodistal relationship between maxillary and mandibular teeth. When Bolton discrepancy is caused by excessive anteroinferior dental volume, it can be corrected in different ways: selective interproximal dental stripping, changes in buccolingual or mesiodistal angulation of anterior teeth, mandibular incisor extraction or by creating space in the upper jaw between laterals and canines. In more severe Bolton discrepancy cases, however, such corrective maneuvers may not be sufficient to achieve adequate occlusion, turning surgery a suitable treatment choice. The main purpose of this paper is to report a case of a segmental orthognatic surgery to correct Bolton Discrepancy. Mandibular incisor extraction (41) associated with mandibular osteotomy to arch constriction was planned to consequently achieve adequate occlusion and facial harmony. Mandibular fragments were mobilized followed by bilateral sagittal split osteotomy. Constriction was conducted accordingly with bone removed from symphysis and segments were fixed with titanium plates and screws (system 2.0). Dental and skeletal transversal pre-existing discrepancy was corrected suggesting that a meticulous surgical planning associated with adequate dental and skeletal mensuration are mandatory to diagnose and treat Bolton discrepancy. Patients’ follow-up showed suitable maxillo-mandibular relationship as well as occlusion stability. Keywords: Orthognathic Surgery, Mandibular Osteotomy, Malloclusion, Dental Arch. Introduction:
AC C
EP
TE
D
One of the goals for success in ortho-surgical treatment is harmonization of upper and lower jaws as well as dental arches. It is suggested that specific mesio-distal relationship should exist between upper and lower jaw teeth to ensure a proper occlusal relationship. Situations where discrepancies occur between arches or teeth sizes, aesthetic and restorative conservative interventions as well as surgical procedures might be planned in order to establish a positive and stable occlusion. When Bolton discrepancy is caused by excessive anteroinferior dental volume, it can be corrected in different ways: selective interproximal dental stripping, changes in buccolingual or mesiodistal angulation of anterior teeth, mandibular incisor extraction or by creating space in the upper jaw between laterals and canines. In more severe Bolton discrepancy cases, however, such corrective maneuvers may not be sufficient to achieve adequate occlusion, turning surgery a suitable treatment choice. It is important to analyze the amount and location of the discrepancy, as well as if it is skeletal or dental- related before establish orthodontic treatment 1,2,3. Bolton discrepancy is the most common discrepancy regarding mesiodistal crown diameters of the upper and lower teeth. Bolton analysis was firstly described in 1958 suggesting that for optimal occlusion, the sum of mesiodistal distance of upper and lower teeth crowns must match 4. This analysis is done directly on study casts, and rotations or other malpositions are not taken into account. Values obtained are used to calculate the Bolton index - percentage obtained by the sum of mesiodistal widths of 12 mandibular teeth (1st molar to 1st molar) divided by the sum of mesiodistal widths of 12 maxillary teeth multiplied by 100. For evaluation of the 12 antagonists teeth (1st molar to 1st molar), the term “overall ratio” is used, and for the two sets of six anterior teeth (canine to canine), “anterior ratio” is used. This analysis is suggested to provide average rates of 91.3 +- 1.91 to overall ratio and 77.2 +- 1.65
ACCEPTED MANUSCRIPT to anterior ratio 4,5. When these ratios are inadequate or when space required to alignment and to a positive occlusion is insufficient, orthodontic treatment plan will count on teeth extraction, interproximal stripping, tilt incisors changes or cosmetic procedures 6,7. Bolton discrepancy correction in association with segmental orthognathic surgery has not been described in literature.
SC
RI PT
Osteotomies in the anterior region of mandible are usually conducted in association with other mandibular osteotomies. Because they are considered supplemental to more complex procedures in the body and/or ramus of mandible, their mention in literature is minimal, however Trauner has described it since 1849 by Hullihan and again in 1952. Segmental osteotomies of the mandibular alveolus are rarely needed when patients are treated with a combination between surgery and orthodontics. Reasons why mandibular osteotomies are avoided are mainly difficulties in maintaining blood supply, periodontal problems and obtaining good bone alignment without grafting 16.
D
M AN U
3-D virtual orthodontic setup, in which the orthodontist predicts the final position and axial inclination of each individual tooth is crucial to surgery planning due to the fact that the surgeon correct skeletal bases according to the patients best occlusion. The ideal interdental site to conduct osteotomies is usually chosen based on arch shape correction objectives as well as the amount of interdental space for a safe osteotomy. Pre-operative periodontal evaluation consisted of a complete periodontal charting. Comprehensive imaging evaluation of the local anatomy with panoramic, postero-anterior cephalometric radiographic, CBCT as well as the use of piezoelectric microsaw should be considered in order to minimize periodontal risks. When surgery is virtually planned, CAD/CAM (computer aided-design and computer aided manufacturing) generates intermediate and final splints to guide safe interdental and mandibular osteotomies.
AC C
EP
TE
Blood supply is suggested to be the most difficult obstacle when segmental alveolar osteotomies are performed, once most alveolar blood supply comes through muscle attachments on the lingual region. Blood supply through bone and through periosteum is limited, which requires the osteotomy segment to be designed in a way that sufficient muscle and overlying soft tissue are maintained on the lingual aspect to ensure bone and teeth viability 16. The aim of this paper is to report an alternative treatment in a dento-facial deformity in which Bolton discrepancy was detected and not amenable to correction with conventional orthodontic treatment. Case Report:
Patient, P.S.T., 42, female, referenced to the Oral and Maxillo-Facial Surgery department of the Federal University of Parana to dental evaluation. Patient was in orthodontic treatment for 4 years and had difficulty in obtaining a satisfactory occlusion. Facial analysis showed a harmonious and symmetrical facial profile, without the need of major surgical intervention to improve aesthetics. Intra-oral assessment, however, showed a class III Angle relationship between molars and canines, and mandibular midline deviation in relation to the facial midline. Imaging and plaster models were evaluated. Proper alignment and dental arches leveling were observed. To determine mesiodistal crown diameter of teeth it was used a needle-pointed orthodontic divider. Interarch teeth measurements confirmed presence of discrepancy associated with front teeth, with anterior ratio of 86.2.
ACCEPTED MANUSCRIPT Surgical set-up through maxillary bone segmentation was conducted but did not improve occlusal relationship. Other treatment modalities, from orthodontic set-ups to interproximal wear and / or teeth extractions were also thought in order to find the best treatment plan.
SC
RI PT
41 extraction associated with segmental orthognathic surgery was elected as the best treatment plan by both orthodontist and surgeon due to the fact that the discrepancy was not evaluated initially by the patients previous orthodontist leading to an unfinished orthodontic treatment that lasted 4 years. If Bolton discrepancy had been evaluated initially, treatment plan would be different and would have involved dental stripping or tooth extraction. In accordance with patients’ needs, orthodontist and surgeon judged as the most reasonable treatment plan to combine orthognatic surgery to correct anteroposterior mandibular excess associated with 41 extraction to correct Bolton discrepancy at the same surgical time. This would facilitate orthodontic mechanics and accelerate orthodontic treatment as well.
M AN U
Both surgeon and orthodontist were concerned about bad periodontal outcomes due to alveolar segmental osteotomies. Regarding this the following parameters were recorded at baseline: plaque index, probing pocket depth (PPD), gingival recession, bleeding on probing, and clinical attachment level (CAL). PPD was measured from the gingival margin with a CP-11 periodontal probe. Gingival recession was measured from the cement-enamel junction to the gingival margin. CAL was calculated by adding the values of gingival recession and PPD. All measurements were made at six sites per tooth (42, 41, 31 and 32) two weeks before surgery: mesio-vestibular, central-vestibular, distovestibular, mesiolingual, central-lingual and distolingual. No alterations in periodontal health was observed.
D
Treatment Plan:
EP
TE
Lower jaw segmentation and concomitant element mandibular incisor (41) tooth extraction, associated with mandibular setback and forward genioplasty was established as treatment plan. The goal of surgical treatment was to promote arc length reduction, aiming to offset the discrepancy. Under general anesthesia, mandibular sagittal split osteotomy was performed bilaterally using reciprocating saw without separating fragments.
AC C
Following, tooth extraction (41) and two vertical osteotomies were performed in mandibular symphysis with parallel orientation to median sagittal plane from mandibular incisor alveolar process until the genioplasty osteotomy line. Piezoelectric microsaw was used to reduce possibilities of periodontal complications. Chin basilar horizontal osteotomy and mobilization of segments were then performed. With all mandibular separated fragments, lower jaw was repositioned with constriction according to the amount of bone removed from vertical osteotomies, thereby correcting the dental transverse discrepancy and pre-existing skeletal (Fig. 2). Segments in both sagittal split ramus osteotomies were fixed with bicortical screws Constricted mandibular segments and mentoplasty were fixed with monocortical titanium plates and screws system 2.0 mm. Tipping of the distal segments were observed, however, it had no clinical repercussion. This inclination generated a maladaptation of proximal segments leading an osseous gap in the midline osteotomy that was filled with autogenous bone graft with bone removed from sagittal osteotomies. Periodontal tissues presented no modifications in immediate post-operatory. After 8 months, patient completed her orthodontic treatment with stable and satisfactory occlusion (Fig. 3).
M AN U
SC
RI PT
ACCEPTED MANUSCRIPT
AC C
EP
TE
D
Figure 1: pre-operative photographs. A) Frontal, oblique and profile photographs were captured in order to evaluate patients facial features before surgical procedure. It is possible to observe chin retraction and lower third of the face shortened. B) Intra-oral assessment showed a Class III Angle Relationship between molars and canines, and mandibular midline deviation in relation to the facial midline. Imaging and models studies were evaluated, revealing proper alignment and dental arches leveling. Mesiodistal measurements were performed and confirmed presence of mismatch associated with front teeth.
Table 1: Demonstrative scheme to measure Bolton discrepancy between superior and inferior dental arches. Mesiodistal mensuration of the six anterior teeth must be conducted in both maxillary and mandibular dental arches using a needle-pointed orthodontic divider. Sum of the mesiodistal distancies of mandibular arch was then divided by the maxillary mesiodistal distancies. As a result, we found an inferior arch discrepancy of 86.2.
M AN U
SC
RI PT
ACCEPTED MANUSCRIPT
AC C
EP
TE
D
Figure 2: Lower jaw segmentation and concomitant element 41 tooth extraction, associated with mandibular setback and forward genioplasty was established. The goal of surgical treatment was to promote arc length reduction, aiming to offset the discrepancy. A and B) Mandibular sagittal osteotomy was performed bilaterally using reciprocating saw without separating fragments. C) Tooth extraction of central right lower incisor (41) was conducted as planned. D) Osteotomy regions marked. E) Two osteotomies were performed in mandibular symphysis with parallel orientation to median sagittal plane from 41 alveolar process until genioplasty region. F) Segments were then fixed with titanium plates and screws system 2.0 mm.
Figure 3: One-year post-operative photographs. A) Extra-oral examination shows a favorable profile as well as patient overall satisfaction. B) intra-oral examination shows satisfactory occlusion. Black-spaces between lower incisors were unexpected side effects of surgical procedure.
AC C
EP
TE
D
M AN U
SC
RI PT
ACCEPTED MANUSCRIPT
Figure 4: panoramic and PA radiographs. A) pre-operative panoramic and PA cefh radiographs and B) immediate post-operative panoramic and PA ceph radiographs.
ACCEPTED MANUSCRIPT
SC
RI PT
Table 2: Safe Interdental Osteotomies.
Discussion
TE
D
M AN U
It is generally accepted that inter-arch mesiodistal crown diameters should match in order a balanced occlusion be achieved. Significant higher overall ratios can be explained by larger mandibular or smaller maxillary arch segments, therefore, a possible association between teeth size and malocclusion may exist. Approximately 91% of orthodontists use Bolton analysis to quantify dental size discrepancies between maxilla and mandible. When orthodontists do not detect those teeth size discrepancies, however, diagnosis would be insufficient and thus harder to obtain a proper occlusion. This mismatch diagnosis may delay treatment completion or may lead to a future retreatment, especially when dental extractions are involved 6. A large percentage of orthodontic patients have significant teeth size discrepancy. If no other discrepancy exists, extraction of one or more teeth could be a reasonable treatment plan, in order to obtain correct interdigitation, overjet, overbite, and tooth alignment 7,8,9.
AC C
EP
When Bolton evaluated plaster models and set a measurement standard, only Class I malocclusion patients were taken into account. Some studies showed, however, that clinical application in patients with other malocclusions types had different values from standards recommended. Studies comparing anterior and total averages from Bolton index to different malocclusion types exhibited higher average, especially in malocclusion Class III patients in agreement with our study (previous excess of 86.2%). Furthermore, authors state that due to frequent previous excess, ideal occlusion Class III patients cannot be obtained, reaffirming the need to a proper diagnosis prior to treatment 10,11,3. Some authors have described Bolton analysis applied to different populations and countries and reported that it is possible to identify different mesiodistal measurements patterns 1, 12. Clinical and dental casts evaluation taking into account the disharmony degree of each case is the gold standard to Bolton discrepancy analysis. Orthodontic and surgical set-ups are crucial to simulate planned results, and decide whether goes for the ortho-surgical treatment or orthodontic treatment only 2,3,7. To determine mesiodistal crown diameter of teeth it was used a needle-pointed orthodontic divider. Over the past years, new techniques and devices have been developed in order to achieve more accurate and reliable teeth measurements, such as electronic needlepointed orthodontic dividers as well as digital calipers 14.
ACCEPTED MANUSCRIPT
RI PT
Defining a treatment plan to a Bolton discrepancy class III patient with or without aesthetic complaints through surgery is a decision that should be taken after untiring analysis and in close collaboration with the orthodontist. Sum values closer to the normal range values could be achieved with less invasive procedures such as selective dental stripping, changes in buccolingual or mesiodistal angulation of anterior teeth, mandibular incisor extraction or by creating space in the upper jaw between laterals and canines 14. Large discrepancies, as reported in this case, however, require less conservative treatments. In this study, due to an extended and misdiagnosed orthodontic treatment, lower incisor extraction associated with mandibular constriction and segmental orthognathic surgery was elected as the best treatment option to correct anteroinferior excess.
M AN U
SC
Literature reports that the most frequent complications of segmental maxillary and mandibular osteotomies are: necrosis of the repositioned maxillary segment, broadening of the alar base, nose tip rotation, and tooth devitalization 16. Other complications to consider are differences in the dentoalveolar region between anterior and posterior segments, bone loss and gingival margin degeneration 17. Sher et al. sent out 135 questionnaires to oral and maxillofacial surgeons in the United States and Canada. The total number of segments osteotomies was 6,195. Complication rate was 0.32%, and the highest prevalence of complications was tooth mobility, injury and teeth lost. The author of the paper suggested that to avoid complications, orthodontics mechanics should be encouraged at the expense of segmentations; avoid interdental osteotomies, if the space between roots is insufficient; and use osteotomes instead of saws 18.
AC C
EP
TE
D
Regarding changes of the bone crest after segmental orthognathic surgery in mandible and maxilla, Dorfman and Turvey 19 documented that a minimum space of 3 mm would be safe for performing interdental osteotomies between two adjacent teeth. They also stated that interdental osteotomies success depends on maintaining an adequate blood supply to the osteotomized segments through planned incisions as well as minimal periosteal detachment in ostetomized segments. Interdental osteotomies must be designed in conjunction with preoperative orthodontics treatment to ensure sufficient space to perform osteotomies. This is an important factor since root divergence is critical to the success of segmental osteotomy 20. Performing interdental osteotomies in regions with restricted interdental radicular space is described as a risk factor for the development of marginal bone loss 21. Authors’ discussion about stability of fragments after mandibular segmental orthognathic surgery, however, has different point of views. This study shows a distal tipping of the fragments. However, it had no clinical implications 19,21,. Regarding surgical procedure, the oldest symphysis osteotomy reference was in 1952, described by Trauner, and modified in 1967 by Sowray et al. to report a case which orthognathic surgery was conducted associated with teeth extraction and constriction of mandibular arch. This procedure is suggested to be a complementary one to a more complex lower jaw procedure. Its mention in literature is minimal 23. Obwegeser in 1988, suggested that a good result can be achieved in a single surgical procedure by associating variations of the main surgical technique. Also suggested that genioplasty can be performed when necessary 15,22. By associating different mandibular movements in a single surgery, it is possible to achieve optimization of surgical time since you have proper planning, experience and professional judgment 24,25. Mentoplasty and mandibular recoiling conducted in the same surgical session of mandibular constriction and teeth
ACCEPTED MANUSCRIPT extraction, in this case proved to be fully applicable and favorable as well as patients’ satisfaction, even though post-operative recovery was required to be more careful 25.
RI PT
Although segmental orthognhatic surgery in the present study was planned due to an unfinished long-term orthodontic treatment, its stability and safety when the technique is performed correctly could extend its indication to other clinical cases to facilitate and save time in orthodontic maneuvers. After 8 months follow-up, patient completed her orthodontic treatment with stable and satisfactory occlusion. Conclusion
M AN U
SC
It is prudent to orthodontists to routinely include occlusion analysis as well as dental and skeletal measurements to identify discrepancies before dental arch final alignment. These measures are key to plan properly and judge the need of less invasive dental procedures or more invasive surgical procedures. A positive and multidisciplinary relationship between surgeon and orthodontist is required in order to achieve success in more complicated clinical cases. References
1 – Smith SS, Buschang PH, Watanabe E. Interarch tooth size relationships of 3 populations:“Does Bolton’s analysis apply?”. American Journal of Orthodontics and Dentofacial Orthopedics. 2000;117(2):169-174.
TE
D
2 - Wędrychowska-Szulc B, Janiszewska-Olszowska J, Stępien P. Overall and anterior Bolton ratio in Class I, II, and III orthodontic patients. Eur J Orthod. 2010;32(3):313–318. 3 – Muqbil I. Analysis of Bolton's tooth size discrepancy for a referred UK population. Thesis. University of Birmingham, 2010.
EP
4- - Bolton WA. Disharmony in tooth size and its relation to the analysis and treatment of malocclusion. Angle Orthodontist. 1958;28(3): 113 – 130
AC C
5- – Bolton WA. The clinical application of a tooth-size analysis. Am J Orthodontics. 1962;48(7):504-529 6- Ileri Z, Basciftci FA, Malkoc S, Ramoglu SI. Comparison of the outcomes of the lower incisor extraction, premolar extraction and non-extraction treatments. Eur J Orthod. 2012;34(6):681-685. 7- Sheridan JJ. The reader’s corner. J ClinOrthod. 2000;34:593-597. 8- Ileri Z, Basciftci FA, Malkoc S, Ramoglu SI. Comparison of the outcomes of the lower incisor extraction, premolar extraction and non-extraction treatments. Eur J Orthod. 2012;34(6):681685.
ACCEPTED MANUSCRIPT 9- Pujol A, Bardinet E, Bazert C, Darque KEA. Extraction of a mandibular incisor. Rev Orthop Dento Faciale. 2001;35(2):185-196. 10 -Færøvig E, Zachrisson BU. Effects of mandibular incisor extraction on anterior occlusion in adults with Class III malocclusion and reduced overbite. Am J Orthod Dentofacial Orthop. 1999;115(2):113-24
RI PT
11- Wędrychowska-Szulc B, Janiszewska-Olszowska J, Stępien P. Overall and anterior Bolton ratio in Class I, II, and III orthodontic patients. Eur J Orthod. 2010;32(3):313–318. 12- Oktay H, Ulukaya E. Intermaxillary tooth size discrepancies among different malocclusion groups. Eur J Orthod. 2010;32(3):307–312
SC
13- Uysal T, Bascificti FA, Goyenc Y. New regression equations for mixed-dentitionarch analysis in a Turkish sample withno Bolton tooth-size discrepancy. Am J Orthod Dentofacial Orthop. 2009;135(3):343-348
M AN U
14- Trauner R. Enlargement and diminution of the chin. Fortschr Keiferorthop 1952;13(2):80-90 15- Eggleston DJ. Correction of unilateral mandibular prognathism by ostectomy of the mandibular symphysis combined with anterior alveolar surgery. Br J Plast Surg. 1976;29(1):3840
D
16- Park JU, Hwang YS. Evaluation of the soft and hard tissue changes after anterior segmental osteotomy on the maxilla and mandible. J Oral Maxillofac Surg. 2008 Jan; 66(1):98103
TE
17- Pingarrón Martín L, Arias Gallo LJ, López-Arcas JM, Chamorro Pons M, Cebrián Carretero JL, Burgueño García M. Fibroscopic findings in patients following maxillary osteotomies in orthognathic surgery. J Craniomaxillofac Surg. 2011 Dec;39(8):588-92
EP
18- Sher MR. A survey of complications in segmental orthognathic surgical procedures. Oral Surg Oral Med Oral Pathol. 1984 Nov; 58(5):537-9
AC C
19- Dorfman HS, Turvey TA. Alterations in osseous crestal height following interdental osteotomies. Oral Surg Oral Med Oral Pathol. 1979 Aug;48(2):120-5 20- Wolford LM, Rieche-Fischel O, Mehra P. Soft tissue healing after parasagittal palatal incisions in segmental maxillary surgery: a review of 311 patients. J Oral Maxillofac Surg. 2002 Jan;60(1):20-5; discussion 26 21- Kwon HJ, Pihlstrom B, Waite DE. Effects on the periodontium of vertical bone cutting for segmental osteotomy. J Oral Maxillofac Surg. 1985 Dec;43(12):952-5. 22- Bloomquist DS. Anterior Segmental Mandibular Osteotomiesfor the Correction of Facial– Skeletal Deformities. Oral Maxillofac Surg Clin North. 2007;19(3):369–379 23- Obwergeser HL. Variations of a Standard Approach for Correction of the Bird-Face Deformity. J Craniomaxfac Surg. 1988;16(6):247-265
ACCEPTED MANUSCRIPT 24- Crosby DR, Alexander CG. The occurrence of tooth sizediscrepancies among different malocclusion groups. Am J Orthodont Dentofac. 1989;95:457-461
AC C
EP
TE
D
M AN U
SC
RI PT
25- Freeman JE, Maskeroni AJ, Lorton L, Meade GG. Frequency of Bolton tooth-size discrepancies among orthodontic patients. Am J Orthodont Dentofacial Orthop. 1996;110(1):24-27
ACCEPTED MANUSCRIPT
TABLE 1
Safe Interdental Osteotomies
AC C
EP
TE D
M AN U
SC
RI PT
1- Adequate space between the roots of laterals and canines (3mm), that is preferably achieved by preoperative orthodontics; 2- Blood supply maintenance (not to detach the segmented periosteum); 3- Burs and ultrasonic tips; 4- Carefully performed or atraumatic surgery; 5- Spatula osteotomies instead of saws.
ACCEPTED MANUSCRIPT
AC C
EP
TE D
M AN U
SC
RI PT
FIGURE 1
ACCEPTED MANUSCRIPT
AC C
EP
TE D
M AN U
SC
RI PT
FIGURE 2
ACCEPTED MANUSCRIPT
AC C
EP
TE D
M AN U
SC
RI PT
FIGURE 2
ACCEPTED MANUSCRIPT
AC C
EP
TE D
M AN U
SC
RI PT
FIGURE 3
ACCEPTED MANUSCRIPT
AC C
EP
TE D
M AN U
SC
RI PT
FIGURE 4
