Art-7-Zhou

Generated from PDF: /home/opencode/cpanel/stomaeduj_hacked/uploads/Art-7-Zhou.pdf
ORAL REHABILITATION                                                                                                                                           www.stomaeduj.com




A MULTIDISCIPLINARY APPROACH FOR THE REHABILITATION




                                                                                                                                                             Case Report
OF A PATIENT WITH CHONDROSARCOMA:
PROSTHETICALLY-DRIVEN DIGITAL WORKFLOW FOR
MAXILLARY RECONSTRUCTION AND IMPLANT TREATMENT
Yanjun Ge1a , Danni Guo1b             , Xiaofeng Shan2c        , Lei Zhang2d      , Ruifang Lu3e      , Pan Shaoxia1f       , Yongsheng Zhou1g*
1
  Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical
Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key
Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health & NMPA
Key Laboratory for Dental Materials, Beijing 100081, China
2
  Department of Oral-Maxillofacial Surgery, Peking University School and Hospital of Stomatology & National Center of Stomatology &
National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology,
Beijing 100081, China
3
  Department of Periodontology, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical
Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key
Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health & NMPA
Key Laboratory for Dental Materials, Beijing 100081, China

a
  DDS, PhD; e-mail: yanjun_ge@163.com; ORCIDiD: https://orcid.org/0000-0003-2853-8657
b
  DDS ; e-mail: gdnsunshine@163.com; ORCIDiD: https://orcid.org/0000-0001-8190-0972
c
  DDS, PhD; e-mail: kqsxf@263.net; ORCIDiD: https://orcid.org/0000-0002-2126-8052
d
  DDS, PhD ; e-mail: zhlei_doctor@sina.com; ORCIDiD: https://orcid.org/0000-0001-8251-6032
e
  DDS, PhD; e-mail: kqrflu@bjmu.edu.cn; ORCIDiD: https://orcid.org/0000-0002-9581-508X
f
  DDS, PhD; e-mail: panshaoxia@vip.163.com; ORCID: https://orcid.org/0000-0002-3808-9499
g
  DDS, PhD, Professor and Head; e-mail: kqzhouysh@hsc.pku.edu.cn; ORCID: https://orcid.org/0000-0002-4332-0878
                                                                                       https://doi.org/10.25241/stomaeduj.2021.8(3).art.7
ABSTRACT
Aim To describe a comprehensive digital therapy oriented towards the final restoration for treating an oral
maxillofacial defect caused by maxillary chondrosarcoma.
Summary The prosthetically-driven multidisciplinary approach was applied to achieve perfectly functional-
aesthetic reconstruction for a male patient with maxillary chondrosarcoma. The complete tumor resection
was ensured by the design of virtual osteotomy and surgical guide plate. A reverse engineering technique
was used to reconstruct the bone defect in the maxillary aesthetic area, which offered reference for a three-
dimensional printing guide plate to shape and fix the free vascularized iliac bone flap. On the solid basis of
previous treatment, the implant placement was performed under the guidance of the prosthetic-driven
implant plate. Vestibular extension and tissue graft were performed to increase keratinized gingiva width to
improve implant-supported fixed prosthesis effect.
Key learning points 1. A multidisciplinary approach including maxillofacial surgery, prosthodontic and
periodontal treatment can provide better esthetic and functional results for complex rehabilitation of a patient
with oral maxillofacial defect. 2. Predictability of maxillary reconstruction and implant restoration can be
increased with prosthetic-driven treatment plan. 3. Applying preoperative virtual design and personalized guide
plate is beneficial to achieve an ideal outline of reconstructed upper jaw. 4. Obtaining comprehensive aesthetic
parameters of the expected restoration is one of the key principles of upper anterior teeth rehabilitation. 5.
Digital technology provides an opportunity for consistency between the primary treatment design and the
final restoration outcome.

KEYWORDS
Digital; Surgical guide; Implant supported restoration; Oral-maxillofacial defect; Multidisciplinary approach

              OPEN ACCESS This is an Open Access article under the CC BY-NC 4.0 license.
              Peer-Reviewed Article
    Citation: Ge Y, Guo D, Shan X, Zhang L, Lu R, Shaoxia P, Zhou Y. A multidisciplinary approach for the rehabilitation of a patient with chondrosarcoma:
    prosthetically-driven digital workflow for maxillary reconstruction and implant treatment. Stoma Edu J. 2021;8(3): 207-215
    Received: September 25, 2021; Revised: September 27, 2021; Accepted: September 29, 2021; Published: September 30, 2021
    *Corresponding author: Prof. Yongsheng Zhou, DDS, PhD, Head; Department of Prosthodontics, Peking University School and Hospital of Stomatology,
    No. 22 Zhongguancun South Avenue, Haidian District, Beijing 100081, P.R. China;
    Tel.: +8610- 82195370; Fax: +8610-62173402; e-mail: kqzhouysh@hsc.pku.edu.cn
    Copyright: © 2020 the Editorial Council for the Stomatology Edu Journal.




Stoma Edu J. 2021;8(3): 207-215                                                                        pISSN 2360-2406; eISSN 2502-0285                       207
                    A multidisciplinary approach for oral rehabilitation
www.stomaeduj.com



                    1. INTRODUCTION                                                         In this article, a maxillary chondrosarcoma case is
Case Reports                                                                                reported to propose a multidisciplinary approach
                    Tumors, trauma or congenital factors mostly lead to an                  and prosthetically-driven digital workflow for the
                    oral-maxillofacial defect. The maxillary defect, especially             oral-maxillofacial rehabilitation.
                    in the anterior teeth area, has a serious impact on
                    patients from both physiological and psychological                      2. CASE PRESENTATION
                    aspects, including bite, pronunciation and aesthetic
                    functions [1,2]. Therefore, as a complex functional                     A 46-year-old male patient required examination
                    and aesthetic reconstruction, the multidisciplinary                     and treatment with the chief complaint of a mass
                    approach is urgently needed to make a comprehensive                     on the front of the maxillary and accompanied by
                    diagnosis and optimal treatment plan, which may                         loose upper anterior teeth for several months, and
                    consist in periodontal, prosthodontic, maxillofacial                    he had no relevant medical history. The general
                    and implant treatment [3].                                              examination showed no abnormalities. The patient
                    Conventional rehabilitation workflow for patients                       visited the Department of Prosthodontics, Peking
                    with oral cancer completes the following steps in                       University School and Hospital of Stomatology in
                    sequence [4]. Surgery is performed to remove the                        February 2018.
                    affected area. The bone defect is reconstructed                         There was a tough mass with a diameter of about
                    with a bone flap or prosthesis. When feasible, the                      3 cm and smooth surface on the labial side of the
                    implant and fixed restoration are used to improve                       maxilla central and lateral incisors (Fig. 1). The
                    the effect. Obviously, there are disadvantages                          vestibular sulcus was swollen without bleeding
                    of the conventional workflow to be optimized.                           and tenderness. Intraoral examination revealed
                    Discontinuous procedures are difficult to ensure                        tooth space among upper anterior teeth, which
                    the treatment consistency. The diagnosis and                            were I degree loose and drifted towards the mesial
                    treatment standards of different specialties are                        direction. Deep overjet and overbite were shown
                    diversified and rely heavily on their experience. In                    on anterior teeth. The first and second right maxilla
                    summary, the complex treatment process reduces                          premolars were missing. The relative position of the
                    the predictability of the rehabilitation [5].                           upper and lower jaws was basically normal. This
                    The development of digital technology provides a                        patient had lots of dental calculus and poor oral
                    variety of means for the optimization of the oral-                      hygiene. The contour of the nasal base and upper
                    maxillofacial defect treatment, such as virtual                         lip was obviously raised, the skin color of the lesion
                    surgery, personalized model made by rapid                               looking normal. There were no abnormalities in the
                    prototyping technique, static plate or dynamic                          region of the neurological lymph nodes and bilateral
                    navigation-guided surgery [6]. The application of                       temporomandibular joint.
                    the novel digital technology can achieve higher                         Cone beam computed tomography (CBCT) showed
                    time efficiency and better quality of outcomes                          one circular area in the maxilla with reduced bone
                    for prosthetic treatment [7]. The implant guide                         density and unclear boundaries closely adhering
                    plate significantly reduces the error of implant                        to the anterior teeth. The range of this lesion was
                    surgery [8]. Precious registration of multi-source                      about 5cmX4cmX3cm, in which spot and flake-
                    data can realize virtual aesthetic design before                        like calcification were visible. The radiographic film
                    surgery. Most of the current scientific evidence of                     revealed neither root canal treatment nor peri-apical
                    applying digital technique for oral-maxillofacial                       resorption of upper anterior teeth (Fig. 2).
                    rehabilitation focuses on mandible reconstruction                       According to the clinical and radiographic
                    and shaping of vascularized fibular flap [5,9-12].                      examination, multidisciplinary experts consulted
                    Literature on maxillary reconstruction in aesthetic                     and gave a comprehensive diagnosis and sequential
                    high-risk area rehabilitated with a free vascularized                   treatment plan. Firstly, the systematic periodontal
                    iliac bone flap assisted by digital technique was rare.                 treatment was performed by the periodontist.




                                                                                             Figure 2. Pre-operative panoramic radiograph indicating the maxilla
                                                                                            with reduced bone density and unclear boundaries lesion close to the
                     Figure 1. A maxillary tumor with a diameter of about 3 cm and smooth   anterior teeth. Neither root canal treatment nor peri-apical resorption
                    surface on the labial side of the upper anterior teeth.                 of upper anterior teeth were noted.




 208                Stoma Edu J. 2021;8(3):207-215                                                             pISSN 2360-2406; eISSN 2502-0285
Ge Y, et al.
                                                                                                                                 www.stomaeduj.com



The oral and maxillofacial surgeons would remove




                                                                                                                                Case Reports
the maxillary tumor and reconstruct the maxilla
for implant restoration. Free gingival grafts would
be performed where required. Subsequently,
implant-supported fixed partial denture would be
accomplished.
The current condition, treatment plan, cost and
prognosis were communicated in detail to the
patient. Signed informed consent, with the aid
of digital technique, virtual surgical planning
(VSP) and rapid prototyping technology (RP) were
applied for maxillary chondrosarcoma resection and
reconstruction. The free vascularized iliac bone graft
                                                           Figure 3. (a)
surgery was performed. The CT dataset of maxillofacial
and iliac were used to simulate the osteotomy
operation and construct a three-dimensional
maxillary defect model through reverse engineering
software. Based on digital design, surgical guide
plates and personalized models were made to assist
in the osteotomy operation and flap fixation (Fig. 3).
A full-thickness flap was raised through intraoral
incision under general anesthesia. The tooth-
supported maxillary surgical guide was completed
in place. According to the preoperative design,
the maxillary lesion was excised (Fig. 4). Taking
pathology analysis and examination together, the
results confirmed the diagnosis of well-differentiated
chondrosarcoma. According to the pathological
                                                          Figure 3. (b)
results of frozen sections, there wereas no tumor
cells at the margin. The free vascularized iliac bone
flap was prepared and shaped under the guidance
of the personalized plate and maxillary model. The
bone flap was adequately positioned at the maxillary
defect area and firmly fixed by titanium nails and
plate. A vascular anastomosis was completed under
the microscope for the successful reconstruction
(Fig. 5). One week, three months and twelve months
after surgery, a clinical examination was performed at
each follow-up visit. Panoramic radiograph and CBCT
showed no recurrence (Fig. 6).
After healing, plaster models were made from primary
                                                           Figure 3. (c)
impressions. A characteristic occlusal rim was made
to record the maxillo-mandibular relationship and
key aesthetic parameters with radiopaque material.
The Digital Imaging and Communications in Medicine
(DICOM) data from CBCT and model scanning data
were registered accurately. Based on the aesthetic
principle, the expected restoration and implant
treatment were virtually designed (Fig. 7). An implant
surgical guide supported by natural teeth and lateral
retention nails was made through the RP technique.
A full-thickness flap was raised under local anesthesia
(Primacaine adrenaline 1:100,000, Dentaires Pierre
Rolland), and four implants(15,13 NobelActive® RP,        Figure 3. (d)
11,21 NobelActive® NP, Institut Nobel Biocare AG) were      Figure 3. Virtual surgical planning (VSP) and rapid prototyping
inserted with the guidance of the template (Fig. 8).      technology (RP) applying for maxillary chondrosarcoma resection
Before suturing, the healing screws were connected        and reconstruction. (a) Virtual osteotomy operation was performed
                                                          using digital technique. (b) 3D printed surgical plate for radical
to the implant. Ten days after surgery, the sutures       resection of maxillary chondrosarcoma. (c) The iliac CT data were
were removed. The examination revealed a favorable        used to simulate maxillary defect reconstruction. (d) A guide plate
healing process of the implant and soft tissue.           for free vascularized iliac bone graft surgery.



Stoma Edu J. 2021;8(3): 207-215                                             pISSN 2360-2406; eISSN 2502-0285                     209
                    A multidisciplinary approach for oral rehabilitation
www.stomaeduj.com

Case Reports


                                                                                                Figure 4. (b)



                    Figure 4. (a)

                      Figure 4. Resection of maxillary chondrosarcoma with the
                    guidance of tooth-supported surgical guide. (a) The surgical
                    guide plate was in place. (b) The maxillary lesion was excised as
                    pre-operative design. (c) The maxillary defect after maxillofacial
                    surgery.



                      Figure 5. Maxillary reconstruction with vascularized iliac bone
                    flap graft surgery. (a) Preparation of free vascularized iliac bone flap.
                    (b) Shaping and fixation of flap with the personalized 3D printed
                    model as reference. (c) The bone flap was adequately positioned at
                    the maxillary defect area and firmly fixed. (d) Completion of vascular
                    anastomosis.                                                                Figure 4. (c)




                     Figure 5. (a)                                                                   Figure 5. (b)




                     Figure 5. (c)                                                              Figure 5. (d)




 210                Stoma Edu J. 2021;8(3):207-215                                                                   pISSN 2360-2406; eISSN 2502-0285
Ge Y, et al.
                                                                                                                                              www.stomaeduj.com




                                                                                                                                            -Case Reports
  Figure 6. Panoramic radiograph showed adequate bone for
implant placement.
                                                                      Figure 8. (a)




                                                                     Figure 8. (b)

 Figure 7. (a)




                                                                      Figure 8. (c)




                                                                      Figure 8. (d)
 Figure 7. (b)                                                         Figure 8. A restoration-oriented digital workflow for implant
                                                                     surgery. (a) Implant treatment was virtually designed using precious
  Figure 7. A prosthetically-driven virtual design for implant       registered dataset. (b) Implant surgical guide was made by rapid
placement. (a) Registration of multi-source data. (b) Implant type   prototyping technology. (c) The implant guide plate was stabilized
and position were virtually designed according to the optimal        through transverse retention nails and residual teeth. (d) Optimal
restoration.                                                         implant placement under the guidance of the plate.



Stoma Edu J. 2021;8(3): 207-215                                                         pISSN 2360-2406; eISSN 2502-0285                     211
                    A multidisciplinary approach for oral rehabilitation
www.stomaeduj.com

Case Reports


                     Figure 9. (a)




                                                                                           Figure 11. Temporary resin restoration milled with a 5-axis CNC machine.


                                                                                           Four months after surgery, the implants showed
                                                                                           good osseointegration. Further intraoral examination
                                                                                           showed less keratinized gingiva on the buccal side of
                                                                                           the right upper jaw. Vestibular extension and tissue
                                                                                           graft were performed to increase keratinized gingiva
                                                                                           width. During the second-stage operation, the 4mm
                                                                                           buccal keratinized gingival was retained through
                                                                                           apically repositioned flap surgery (Fig. 9). The screws
                    Figure 9. (b)
                                                                                           were unscrewed, and the healing abutments were
                                                                                           connected to the implants (Fig. 10).
                                                                                           Communicating with the patient, the final restoration
                                                                                           was screw-retained zirconia base with labial porcelain
                                                                                           fixed bridge. For the upper jaw, an open-tray splint
                                                                                           implant impression was taken with a polyether material
                                                                                           (Impregum Penta, 3M ESPE GmbH). A conventional
                                                                                           impression of the opposing jaw was taken with
                                                                                           alginate material (Alginoplast, Heraeus Kulzer GmbH).
                                                                                           Temporary resin restoration was milled with a 5-axis CNC
                                                                                           machine. Trying in the temporary restoration, passive
                                                                                           fit and appropriate upper lip fullness were achieved
                                                                                           (Fig. 11). Referred to the pupil line and smile line, minus
                                                                                           adjustment of the denture was performed on the
                     Figure 9. (c)                                                         restoration to obtain coordinated midline and incisal
                                                                                           curve. After three months, the patient did not express
                      Figure 9. Tissue graft to increase width of the keratinized          discomfort. The maxillo-mandibular relationship was re-
                    gingiva. (a) A deficiency of the keratinized gingiva on the buccal
                    side of the right upper jaw. (b) Performance of vestibular extension
                                                                                           determined and transferred to the articulator by face-
                    and tissue graft. (c) The second-stage operation and apically          bow. The final zirconium restoration was made with the
                    repositioned flap surgery.                                             reference of the temporary restoration. At delivery, the
                                                                                           interproximal contact points were assessed for a strong
                                                                                           contact using dental floss. Occlusal contact points were
                                                                                           checked for light occlusal contacts without lateral
                                                                                           occlusal disturbance (Arti‐Fol shimstock foil, Dr. Jean
                                                                                           Bausch GmbH & Co.). With a small amount of modified
                                                                                           occlusal contact, the patient showed high satisfaction
                                                                                           for the effect and comfort (Fig. 12). The panoramic
                                                                                           radiograph showed good marginal adaptation of final
                                                                                           restoration (Fig. 13). Twelve months after delivery, the
                                                                                           follow-up examination revealed restoration in good
                                                                                           condition. Oral hygiene maintenance and regular
                     Figure 10. Panoramic radiograph after osseointegration of implants.   recheck were instructed (Fig. 14).


 212                Stoma Edu J. 2021;8(3): 207-215                                                           pISSN 2360-2406; eISSN 2502-0285
Ge Y, et al.
                                                                                                                                                           www.stomaeduj.com




                                                                                                                                                          Case Reports
                                                                            Figure 13. Panoramic radiograph after final restoration showed passive fit.




 Figure 12. (a)




                                                                             Figure 14. (a)

 Figure 12. (b)




 Figure 12. (c)


                                                                             Figure 14. (b)

                                                                             Figure 14. Twelve months after delivery. (a) Restoration in good
                                                                            condition (b) Well maintained oral hygiene.


                                                                            3. DISCUSSION

                                                                            In this case, the patient was diagnosed with maxillary
 Figure 12. (d)                                                             chondrosarcoma, which is a rare malignant neoplasm
                                                                            [13]. Chondrosarcoma(CHS) usually occurs in the pelvis,
                                                                            chest wall, and scapula. Maxillary chondrosarcoma is
                                                                            more common in men, average age range from 35
                                                                            to 45 years old [14]. Maxillary chondrosarcoma may
                                                                            originate from the embryonic cartilage precursors
                                                                            of turbinate and nasal septum. According to the
                                                                            characteristics of the cells under the microscope,
                                                                            this patient is pathologically diagnosed as highly
 Figure 12. (e)                                                             differentiated chondrosarcoma, classified as Grade I.
  Figure 12. Perfect functional-aesthetic reconstruction with final         The 5-year survival rate for patients with grade I is 89%,
implant supported fixed partial denture. (a) Occlusal view. (b) Centric
occlusion-right. (c) Centric occlusion-left. (d) The color and contour of   according to WHO data [13,15]. Therefore, it is necessary
the restoration are consistent with adjacent teeth. (e) The gingival end    to provide complete treatment and a rehabilitation
of the bridge is in harmony with the soft tissue.                           plan for this patient to improve his survival life quality.


Stoma Edu J. 2021;8(3): 207-215                                                                pISSN 2360-2406; eISSN 2502-0285                            213
                    A multidisciplinary approach for oral rehabilitation
www.stomaeduj.com



                    Prosthetic-driven multidisciplinary approach is                            Implant restoration can effectively improve the
Case Reports        an important concept for maxillofacial defect                              rehabilitation outcome of patients with maxillofacial
                    rehabilitation [5]. Radical resection of the affected                      defects. It is reported that the cumulative survival rate
                    area of maxillary chondrosarcoma is the sole way to                        of implants placed in bone flaps in jaw rehabilitation
                    achieve an optimal outcome. However, common hard                           can reach 93.2% [20]. It should be noted that the
                    and soft tissue defects after resection always make it                     long-term good prognosis of implant restoration is
                    too difficult to complete optical restoration. In this case,               closely related to the dentist’s treatment as well as
                    under the guidance of final implant supported fixed                        the patient’s maintenance. A reasonable preoperative
                    restoration, the key parameters were formulated to                         design ensures a good self-cleaning for the patient.
                    shape the iliac bone flap, and to restore the contour                      Hygiene maintenance and regular review effectively
                    and bone mass of the maxillary defect area. Based                          reduce complications. The limitation of this case report
                    on the solid foundation, ideal implant surgery can be                      is that the temporary denture does not use digital
                    performed as the established design with the aid of a                      preoperative design. The application of the fully digital
                    digital surgical guide plate. At the same time, a plan to                  workflow can further ensure the guiding role of the
                                                                                               final restoration. The conventional workflow used in
                    increase the width of keratinized gingiva with palatal
                                                                                               this case report is a time-saving and mature method.
                    mucosal transplantation is made when necessary
                                                                                               The long-term repair effect needs to be further tracked.
                    [19]. Prosthetic-driven treatment can improve the
                    predictability of rehabilitation effect, the consistency                   4. CONCLUSION
                    of multidisciplinary treatment standards and the
                    effectiveness of communication with patients.                              In this case, a new concept of multidisciplinary
                    The application of computer aided surgery (CAS) has                        diagnosis and treatment approach is used to complete
                    significantly improved the accuracy and safety of the                      the maxillary reconstruction and implant supported
                    jaw reconstruction. Based on different bone defects,                       fixed restoration for the maxillary chondrosarcoma
                    guided bone regeneration (GBR), onlay bone graft,                          patient. The prosthetic-driven workflow can achieve
                    distraction osteogenesis, or vascularized bone flap graft                  the consistency of complex treatment standards and
                    can be selected for reconstruction [17-19]. As agreed                      improve the predictability of the restoration. The
                    with the patient, the vascularized iliac bone flap was                     accuracy and efficiency of the treatment are improved
                    chosen to reconstruct his maxilla. Three common digital                    with digital technology.
                    techniques are navigation surgery, guide plate, and a                      CONFLICT OF INTEREST
                    combination of navigation and plate, which can be                          The authors declare no conflict of interest.
                    selected according to the purpose of the operation and                     ACKNOWLEDGMENTS
                    scope of the defect. In this case, using a static guide                    None
                    plate as appropriate auxiliary method to accurately                        AUTHOR CONTRIBUTIONS
                    guide osteotomy and fixation of the flap, consists three                   *Yanjun Ge and Danni Guo have equally contributed as first authors.
                                                                                               DG and YG collected data and wrote the original draft. YG, XS, LZ
                    key steps: obtaining registered data pre-operation,                        and RL performed the clinical treatment. SP and YZ lead the writing
                    virtual surgical planning, application of rapid prototype.                 and revised the manuscript.

                    REFERENCE
                    1. Warnakulasuriya S. Global epidemiology of oral and                      10.1016/j.bjoms.2019.10.310. Epub 2019 Nov 11. PMID: 31718915.
                    oropharyngeal cancer. Oral Oncol. 2009 Apr-May;45(4-5):309-316.            Full text links PubMed Google Scholar Scopus WoS
                    doi: 10.1016/j.oraloncology.2008.06.002. Epub 2008 Sep 18. PMID:           7. Pan S, Guo D, Zhou Y, et al. Time efficiency and quality of
                    18804401.                                                                  outcomes in a model-free digital workflow using digital impression
                    Full text links CrossRef PubMed Google Scholar Scopus WoS                  immediately after implant placement: a double-blind self-controlled
                    2. Brown JS, Shaw RJ. Reconstruction of the maxilla and midface:           clinical trial. Clin Oral Implants Res. 2019 Jul;30(7):617-626. doi:
                    introducing a new classification. Lancet Oncol. 2010 Oct;11(10):1001-      10.1111/clr.13447. Epub 2019 May 13. PMID: 31021451.
                    1008. doi: 10.1016/S1470-2045(10)70113-3. PMID: 20932492.                  Full text links CrossRef PubMed Google Scholar Scopus WoS
                    Full text links CrossRef PubMed Google Scholar Scopus WoS                  8. Liu X, Liu J, Feng H, Pan S. Accuracy of a milled digital implant
                    3. Zhang DS, Zheng JW, Zhang CP, et al. [Multidisciplinary team            surgical guide: an in vitro study. J Prosthet Dent. 2020 Dec 10:S0022-
                    model for patients with oral cancer and systemic diseases: an expert       3913(20)30654-5. doi: 10.1016/j.prosdent.2020.07.041. Epub ahead
                    consensus]. Hua Xi Kou Qiang Yi Xue Za Zhi. 2020 Dec 1;38(6):603-615.      of print. PMID: 33309294.
                    Chinese. doi: 10.7518/hxkq.2020.06.001. PMID: 33377335; PMCID:             Full text links PubMed Google Scholar Scopus
                    PMC7738912.                                                                9. Qiu SY, Kang YF, Ding MK, et al. Mandibular reconstruction with
                    Full text links PubMed Google Scholar Scopus WoS                           the iliac flap under the guidance of a series of digital surgical guides.
                    4. Levine JP, Bae JS, Soares M, et al. Jaw in a day: total maxillofacial   J Craniofac Surg. 2021 Jul-Aug 01;32(5):1777-1779. doi: 10.1097/
                    reconstruction using digital technology. Plast Reconstr Surg. 2013         SCS.0000000000007494. PMID: 33534315.
                    Jun;131(6):1386-1391. doi: 10.1097/PRS.0b013e31828bd8d0. PMID:             Full text links CrossRef PubMed Google Scholar Scopus WoS
                    23714799.                                                                  10. Harbison RA, Shan XF, Douglas Z, et al. Navigation guidance
                    Full text links PubMed Google Scholar Scopus WoS                           during free flap mandibular reconstruction: a cadaveric trial. JAMA
                    5. Tian T, Zhang T, Ma Q, et al. Reconstruction of mandible: a fully       Otolaryngol Head Neck Surg. 2017 Mar 1;143(3):226-233. doi: 10.1001/
                    digital workflow from visualized iliac bone grafting to implant            jamaoto.2016.3204. Erratum in: JAMA Otolaryngol Head Neck Surg.
                    restoration. J Oral Maxillofac Surg. 2017 Jul;75(7):1403.e1-1403.e10.      2017 Mar 1;143(3):318. PMID: 27893003; PMCID: PMC8025841.
                    doi: 10.1016/j.joms.2017.02.022. Epub 2017 Mar 7. PMID: 28359016.          Full text links PubMed Google Scholar Scopus WoS
                    Full text links CrossRef PubMed Google Scholar Scopus WoS                  11. Nguyen TTH, Eo MY, Myoung H, et al. Implant-supported fixed
                    6. Zhang HQ, Li QX, Wang YY, et al. Combination of biomechanical           and removable prostheses in the fibular mandible. Int J Implant
                    evaluation and accurate placement of dental implants: a new                Dent. 2020 Aug 11;6(1):44. doi: 10.1186/s40729-020-00241-7. PMID:
                    concept of virtual surgery in maxillary and mandibular functional          32778982; PMCID: PMC7417466.
                    reconstruction. Br J Oral Maxillofac Surg. 2020 Jan;58(1):62-68. doi:      Full text links CrossRef PubMed Google Scholar WoS




 214                Stoma Edu J. 2021;8(3): 207-215                                                                pISSN 2360-2406; eISSN 2502-0285
Ge Y, et al.
                                                                                                                                                  www.stomaeduj.com



12. Kataoka T, Akagi Y, Kagawa C, et al. A case of effective oral         17. Zhang WB, Peng X, Yu Y, et al. Expert consensus for the




                                                                                                                                                 Case Reports
rehabilitation after mandibular resection. Clin Case Rep. 2019 Sep        treatment algorithm for navigation assisted reconstruction of
27;7(11):2143-2148. doi: 10.1002/ccr3.2459. PMID: 31788267; PMCID:        maxillofacial deformities. Chin J Dent Res. 2020;23(1):33-42. doi:
PMC6878091.                                                               10.3290/j.cjdr.a44334. PMID: 32232227.
Full text links CrossRef PubMed Google Scholar Scopus WoS                 Full text links PubMed Google Scholar Scopus
13. de Souza LL, Pontes FSC, Fonseca FP, et al. Chondrosarcoma of the
                                                                          18. Kang YF, Liang J, He Z, et al. Orbital floor symmetry after
jaw bones: a review of 224 cases reported to date and an analysis of
prognostic factors. Int J Oral Maxillofac Surg. 2019 Apr;48(4):452-460.   maxillectomy and orbital floor reconstruction with individual
doi: 10.1016/j.ijom.2018.11.006. Epub 2018 Dec 6. PMID: 30528199.         titanium mesh using computer-assisted navigation. J Plast
Full text links CrossRef PubMed Google Scholar Scopus WoS                 Reconstr Aesthet Surg. 2020 Feb;73(2):337-343. doi: 10.1016/j.
14. Karadwal A, Chatterjee S. Chondrosarcoma of maxilla. J Oral           bjps.2019.07.014. Epub 2019 Aug 7. PMID: 31477492.
Maxillofac Pathol. 2018 Jan;22(Suppl 1):S35-S38. doi: 10.4103/jomfp.      Full text links CrossRef PubMed Google Scholar Scopus WoS
JOMFP_169_15. PMID: 29491602; PMCID: PMC5824514.                          19. Li R, Meng Z, Zhang Y, et al. Soft tissue management: a
Full text links PubMed Google Scholar                                     critical part of implant rehabilitation after vascularized free-flap
15. Cuevas-Gonzalez JC, Reyes-Escalera JO, Gonzalez JL, et al. Primary    reconstruction. J Oral Maxillofac Surg. 2021 Mar;79(3):560-574.
maxillary chondrosarcoma: a case report. World J Clin Cases. 2020 Jan     doi: 10.1016/j.joms.2020.11.006. Epub 2020 Nov 14. PMID:
6;8(1):126-132. doi: 10.12998/wjcc.v8.i1.126. PMID: 31970178; PMCID:      33279473.
PMC6962084.
                                                                          Full text links PubMed Google Scholar Scopus WoS
Full text links PubMed Google Scholar Scopus WoS
16. De Cicco D, Colella G, Tartaro G, et al. Wide anterior maxillary      20. Zhang L, Ding Q, Liu C, et al. Survival, function, and
reconstruction with equine bone xenograft: a case report of               complications of oral implants placed in bone flaps in jaw
24-month follow-up. Case Rep Surg. 2020 Oct 21;2020:8890935. doi:         rehabilitation: a systematic review. Int J Prosthodont. 2016 Mar-
10.1155/2020/8890935. PMID: 33145117; PMCID: PMC7596435.                  Apr;29(2):115-25. doi: 10.11607/ijp.4402. PMID: 26929947.
Full text links CrossRef PubMed Google Scholar WoS                        Full text links CrossRef PubMed Google Scholar Scopus WoS



                                                                                                          Yanjun GE
                                                                                               DDS, PhD
         Department of Prosthodontics; Peking University School and Hospital of Stomatology National
        Center of Stomatology; National Clinical Research Center for Oral Diseases; National Engineering
        Laboratory for Digital and Material Technology of Stomatology; Beijing Key Laboratory of Digital
              Stomatology Research Center of Engineering and Technology for Computerized Dentistry
                     Ministry of Health; NMPA Key Laboratory for Dental Materials, Beijing 100081, China


CV
Dr. Ge, DDS, has been a prosthodontist and lecturer at Peking University School and Hospital of Stomatology since 2009. As an
ITI member, he carried out a large number of implant treatments using digital technology. He is good at and responsible for
treating prosthetic patients, especially complex case treated with the multidisciplinary approach.


Questions
1. What is the average age range of male patients with maxillary chondrosarcoma?
q a. 40 to 55;
q b. 35 to 45;
q c. 25 to 36;
q d. 65 to 75.

2. Which of the following options is not a method for maxillofacial surgery to reconstruct
the maxilla?
q a. Distraction osteogenesis;
q b. Vascularized bone flap graft;
q c. GBR;
q d. Obturator.

3. Which is the digital method commonly used in computer-assisted surgery?
q a. Navigation surgery;
q b. Surgical guide plate;
q c. Virtual surgical planning;
q d. All of the above.

4. What is the retention survival rate of implants on the bone flap (jaw reconstruction)?
q a. 78.5%;
q b. 93.2%;
q c. 96.8%;
q d. 89.7%.



Stoma Edu J. 2021;8(3): 207-215                                                              pISSN 2360-2406; eISSN 2502-0285                     215