A pilot study of masticatory function after maxillectomy comparing rehabilitation with an obturator prosthesis and reconstruction with a digitally planned, prefabricated, free, vascularized fibula flap

Asymmetry of the alveolar ridge in Class II maxillary defects reconstructed by an osseo-myocutaneous flap: A CBCT evaluation

STATEMENT OF PROBLEM

Alveolar ridge asymmetry remains in patients with Class II maxillary defects reconstructed by osseo-myocutaneous flaps, leading to esthetic and functional issues. Implant-supported fixed dental prostheses (IFDPs) might have the potential to improve facial appearance related to this asymmetry, but studies on this topic are lacking.

PURPOSE

The purpose of this clinical study was to determine whether IFDPs effectively improve facial appearance related to alveolar ridge asymmetry after maxillary reconstruction by using cone beam computed tomography (CBCT) based on treating the patients with IFDPs for comparable dentition defects as control.

MATERIAL AND METHODS

Sixteen patients with Class II maxillary defects who underwent reconstruction were the study group, while 16 patients with IFDPs for comparable dentition defects were the control group. CBCT images were used to obtain 3-dimensional coordinates of landmarks and the nasolabial angle. Reference planes were established and 3 anatomic landmarks related to the alveolar ridge were defined by using a constructed coordinate plane system. Asymmetry indices of the landmarks were then calculated to assess the asymmetry of reconstructed alveolar ridge. The Welch t and Mann-Whitney tests were performed to compare the differences in 3-dimensional vectors of each landmark between the groups. Additionally, both the independent samples t and chi-squared tests were used to compare the nasolabial angle between the groups (α=.05 for all tests).

RESULTS

Compared with patients with IFDPs for comparable dentition defects, the alveolar ridge asymmetry of reconstructed patients becomes increasingly pronounced from the anterior to the posterior zone. Quantitative analysis revealed this asymmetry was mainly because of vertical discrepancies at middle point (MP) (Δdy=3.72±4.44 mm, P=.003) and posterior point (ZB) (Δdz=4.05±7.20 mm, P=.010; Δdy=3.11±4.43 mm, P=.032). However, there was no significant difference in nasolabial angle between the 2 groups (P=.219).

CONCLUSIONS

Alveolar ridges reconstructed with osseo-myocutaneous flaps in Class II defects displayed acceptable asymmetry in the anterior zone. Bony reconstruction of anterior maxilla can support soft tissue lateral profile with the aid of IFDPs. Although posterior alveolar ridge showed mesial yawing, upward shifting, and less distal extension, IFDPs still could effectively improve the facial profile.

Maxillary Reconstruction with Free Vascularized Fibula: 15-Year Experience

BACKGROUND

Reconstruction of the midface after maxillectomy is extremely challenging because of the need to reestablish the contour of the midface, maintain oronasal separation, support the orbit, and to restore the dentition. In this study, the authors present their specific technique, surgical and functional outcomes, and pitfalls to avoid for reconstruction of the midface with the fibula osteocutaneous free flap.

METHODS

A retrospective review of patients who underwent maxillary reconstruction with a fibula osteocutaneous free flap was performed.

RESULTS

Eighty-five flaps were performed in 73 patients (61 patients received a fibula flap only; 12 patients received an additional soft-tissue free flap). Reconstructions were performed for Cordeiro type 2 (82.2%) and Cordeiro type 3a (18.8%) defects. Osseointegrated dental implants were placed in 95.9% of patients, 13.7% of whom underwent immediate implant placement. Concurrent orbital floor reconstruction was performed in 16.2% of patients. The rate of operative take-back was 18.9%, and total flap loss occurred in 2.7%. Hardware exposure occurred in 11.0% at a mean of 4.4 years postoperatively and palatal fistulas occurred in 5.5%, usually within the first 3 weeks following reconstruction. Functionally, 79.5% demonstrated excellent speech and 80.9% had unrestricted diet postoperatively. The mean follow-up period was 3.4 years.

CONCLUSIONS

The present study shows that maxillary reconstruction with free fibula flap provides reliable reconstruction that restores dental, orbital, and midfacial support. Modifications and nuances to the reconstructive technique learned over time to avoid complications and improve outcomes are described herein.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Rehabilitation of patients with maxillary defects: A network meta-analysis

STATEMENT OF PROBLEM

Different treatments for maxillary defects have been described, but a meta-analysis of these treatments to provide clinical guidance is lacking.

PURPOSE

The purpose of this systematic review and network meta-analysis was to evaluate the effect of tissue-supported obturator prostheses and other rehabilitation treatments for patients with maxillary defects on patient-reported outcome measures (PROMs) assessed through quality of life (QoL) questionnaires.

MATERIAL AND METHODS

Inclusion criteria were parallel-arm randomized controlled trials (RCTs) and nonrandomized studies of intervention (NRSIs) with a tissue-supported obturator as one of the treatments. Nine databases and nonpeer-reviewed literature were searched. Independent reviewers selected studies, extracted data, and assessed the risk of bias. Seven outcomes were analyzed separately for RCTs and NRSIs: appearance, mastication, pain, social contact, speech, swallowing, and QoL. A Bayesian random-effect network meta-analysis (NMA) calculated mean differences (MD) and 95% credible interval (Crl) for each treatment comparison. Data interpretation followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach and the magnitude of the effect was calculated as the minimal important difference (MID) - the minimal clinical benefit for the patient - for each outcome.

RESULTS

The review included 4 RCTs and 9 NRSIs. Most studies had a high and critical risk of bias. There were 7 treatments: no reconstructive or rehabilitative treatment, surgical obturator, interim obturator, tissue-supported obturator, implant-supported obturator, magnet obturator, and flap, totaling 120 treatment comparisons (56 among RCTs and 64 among NRSIs). Some treatments reached the minimum clinical benefit (MID). However, the 95%Crl crossed the null effect line for all treatment comparisons, indicating that any treatment can be efficient. The certainty of the evidence was very low for all comparisons, mainly because of the risk of bias, indirectness, intransitivity, and imprecision.

CONCLUSIONS

No treatment was better than another for any outcome. More RCTs comparing treatments for the rehabilitation of maxillary defects are encouraged to improve the evidence.

A generalizable procedure for Brown's class Ⅱ and Ⅲ defects reconstruction with deep circumflex iliac artery flap using computer-assisted technique

OBJECTIVE

This study summarizes and analyzes the characteristics of deep circumflex iliac artery (DCIA) flap reconstruction for maxillary defects and proposes a generalized protocol under the guidance of computer-assisted technique to enhance surgical efficiency and success rate.

MATERIALS AND METHODS

We retrospectively reviewed 10 cases of maxillary defects reconstructed using DCIA flaps under the application of computer-assisted technique, collecting clinical data for statistical analysis.

RESULTS

These cases included 2 cystic lesions, 2 mucinous tumors, 2 ameloblastomas, 1 mucoepidermoid carcinoma, 1 odontogenic fibroma, 1 bone defect following squamous cell carcinoma (SCC) surgery, and 1 ossifying fibroma. According to Brown's classification system, there were 7 Type IIb defects, 1 Type IId defect, 1 Type IIIb defect, and 1 Type IIId defect. The length of the iliac bone harvested ranged from 42 mm to 100 mm, and the width from 20 mm to 51 mm. In 7 patients, chimeric iliac myofascial flaps were used; in 2 patients, deep circumflex iliac artery perforator (DCIAP) flaps were utilized; and in 1 patient, a vascularized iliac crest was employed. The recipient vessels were the facial artery and vein in all cases. Intraoral anastomoses were performed in 4 cases, and submandibular anastomoses in 6 cases. The donor site was chosen from the ipsilateral ilium in 8 patients and from the contralateral ilium in 2 patients. The mean operative time was 8.74 hours. Postoperatively, 9 patients recovered well without any complications, while 1 patient experienced necrosis of the bone flap on the first day after surgery and underwent secondary reconstruction using a vascularized fibula flap. The average postoperative hospital stay was 8.6 days.

CONCLUSION

The combination of DCIA flaps with computer-assisted technique provides a reliable method for the reconstruction of maxillary defects and functional restoration. Establishing generalized procedures could facilitate its broader application.

Comparative analysis of surgical and prosthetic rehabilitation in maxillectomy: A systematic review and meta-analysis on quality-of-life scores and objective speech and masticatory measurements

STATEMENT OF PROBLEM

Patients with oro-antral communication, whether from trauma, disease, or congenital anomalies, have options for surgical reconstruction or prosthetic obturation, but guiding interdisciplinary protocols are lacking.

PURPOSE

The purpose of this systematic review and meta-analysis was to compare surgical reconstruction and prosthetic obturation, identifying correlations with baseline characteristics to determine the most effective approach for specific patients.

MATERIAL AND METHODS

A systematic search was conducted in 4 databases. Searching, screening, data extraction, and risk of bias assessment were performed by 2 reviewers. Eligible studies focused on patients with palatomaxillary defects from cancer-related maxilla surgeries. Traumatic or congenital defects were excluded. The study compared prosthetic restoration (either with surgical or definitive obturators) to surgical reconstruction using flaps or grafts. Patients with surgical restoration after tooth extraction were excluded. Both subjective and objective outcomes were used for comparison.

RESULTS

Thirteen articles were included in the qualitative synthesis and 9 in the meta-analysis. Patient scores on quality-of-life questionnaires, objective speech, and masticatory ability evaluations were compared. The number of patients who underwent surgical reconstruction was 206, whereas 260 patients received prosthetic obturators. Results showed no significant differences. In the "activity" domain of the University of Washington QoL questionnaire, however, the 1.92 (0.45, 3.40) score difference was not clinically relevant. However, the heterogeneity of trials, the transient nature of subjective evaluations, the low number of participants, and major confounding biases did not allow a solid conclusion to be drawn.

CONCLUSIONS

The growing number of maxillectomy patients demands firm evidence on which rehabilitation to choose and when it should be done. The result suggests that obturator devices and surgical reconstruction have similar effects on quality of life and health outcomes. A multicentric registry in which patient strata could be analyzed separately by age, adjuvant therapies, defect sizes, and remaining dentition is advocated.

Digital workflow feasibility for the fabrication of intraoral maxillofacial prosthetics after surgical resection: a systematic literature review

OBJECTIVES

To evaluate the current evidence of digital workflow feasibility based on the data acquisition methods and the software tools used to fabricate intraoral prostheses for patients with partial or total maxillary and mandibular defects.

MATERIALS AND METHODS

An electronic search was performed in PubMed, SCOPUS, and Web of Science using a combination of relevant keywords: digital workflow, digital designing, computer-assisted design-computer aided manufacturing, 3D printing, maxillectomy, and mandibulectomy. The Joanna Briggs Institute Critical Appraisal Tool was used to assess the quality of evidence in the studies reviewed.

RESULTS

From a total of 542 references, 33 articles were selected, including 25 on maxillary prostheses and 8 on mandibular prostheses. The use of digital workflows was limited to one or two steps of the fabrication of the prostheses, and only four studies described a complete digital workflow. The most preferred method for data acquisition was intraoral scanning with or without a cone beam computed tomography combination.

CONCLUSION

Currently, the fabrication process of maxillofacial prostheses requires combining digital and conventional methods. Simplifying the data acquisition methods and providing user-friendly and affordable software may encourage clinicians to use the digital workflow more frequently for patients requiring maxillofacial prostheses.

A fully digital workflow for the design and manufacture of a class of metal orthodontic appliances

Background

Traditional working procedures requires a lot of clinical processes and processing time.

Methods

The orthodontic metal appliances were made by applying oral scanners, digital images, computer-aided design and computer-aided manufacturing (CAD-CAM) printers.

Results

The computer digital technology simplified the manufacturing process for dental appliances and shorten the duration for clinical operation and technical processing.

Conclusions

The technique described in this paper can guarantee the accuracy of orthodontic appliances and bring revolution the field.

Clinical significance

The CAD-CAM technology provides a fully digital workflow for manufacturing metal orthodontic appliances, which saves a considerable amount of labor and material costs, and significantly reduces heavy metal pollution in the working environment of dental technicians.

Microvascular Free Flap Outcomes in Maxillectomy Defects from Invasive Fungal Sinusitis

OBJECTIVES

Microvascular free tissue transfer is routinely used for reconstructing midface defects in patients with malignancy, however, studies regarding reconstructive outcomes in invasive fungal sinusitis (IFS) are lacking. We aim to describe outcomes of free flap reconstruction for IFS defects, determine the optimal time to perform reconstruction, and if anti-fungal medications or other risk factors of an immunocompromised patient population affect reconstructive outcomes.

METHODS

Retrospective review of reconstruction for IFS (2010-2022). Age, BMI, hemoglobin A1c, number of surgical debridements, and interval from the last debridement to reconstruction were compared between patients with delayed wound healing versus those without. Predictor variables for delayed wound healing and the effect of time on free flap reconstruction were analyzed.

RESULTS

Twenty-seven patients underwent free flap reconstruction for IFS. Three patients were immunocompromised from leukemia and 21 had diabetes mellitus (DM). Patients underwent an average of four surgical debridements for treatment of IFS. The interval from the last IFS debridement to flap reconstruction was 5.58 months (±5.5). Seven flaps (25.9%) had delayed wound healing. A shorter interval of less than 2 months between the last debridement for IFS and reconstructive free flap procedure was associated with delayed wound healing (Fisher Exact Test p = 0.0062). Other factors including DM, BMI, HgA1c, and bone reconstruction were not associated with delayed wound healing.

CONCLUSION

Patients with maxillectomy defects from IFS can undergo microvascular-free flap reconstruction with good outcomes while on anti-fungal medication. Early reconstruction in the first 2 months after the last IFS debridement is associated with delayed wound healing.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1642-1647, 2024.

Oral Rehabilitation of Marginal Maxillectomy Patient After Local Flap Reconstruction

The treatment of oral cancer can lead to various oral complications, including oral defects, tissue deformation, and trismus in patients who have undergone oral cancer surgery with resection of any part of the maxillary. Restoring the ability to chew, swallow, and maintain esthetics is essential and a significant challenge. The aim of this study was to report a successful clinical case of preprosthetic surgery and prosthetic rehabilitation of a 65-year-old man who had undergone marginal maxillectomy, resulting in tissue scarring and a significant reduction in maximal mouth opening. The oral rehabilitation was achieved using a conventional removable prosthesis. This case demonstrates that preprosthetic surgery combined with conventional removable prosthesis is an effective strategy for complex rehabilitations providing functional and esthetic improvement in the affected area for patients with marginal maxillectomies resulting from oral cancer.

Development and validation of a novel craniofacial statistical shape model for the virtual reconstruction of bilateral maxillary defects

Bilateral maxillary defects are a challenge for fibula free flap reconstruction (FFFR) surgery due to limitations in virtual surgical planning (VSP) workflows. While meshes of unilateral defects can be mirrored to virtually reconstruct missing anatomy, Brown class c and d defects lack a contralateral reference and associated anatomical landmarks. This often results in poor placement of osteotomized fibula segments. This study was performed to improve the VSP workflow for FFFR using statistical shape modeling (SSM) - a form of unsupervised machine learning - to virtually reconstruct premorbid anatomy in an automated, reproducible, and patient-specific manner. A training set of 112 computed tomography scans was sourced from an imaging database by stratified random sampling. The craniofacial skeletons were segmented, aligned, and processed via principal component analysis. Reconstruction performance was validated on a set of 45 unseen skulls containing various digitally generated defects (Brown class IIa-d). Validation metrics demonstrated promising accuracy: mean 95th percentile Hausdorff distance of 5.47 ± 2.39 mm, mean volumetric Dice coefficient of 48.8 ± 14.5%, compactness of 7.28 × 105 mm2, specificity of 1.18 mm, and generality of 8.12 × 10-6 mm. SSM-guided VSP will allow surgeons to create patient-centric treatment plans, increasing FFFR accuracy, reducing complications, and improving postoperative outcomes.

Virtual Surgical Planning in Free Tissue Transfer for Orbito-Maxillary Reconstruction

Since its introduction, virtual surgical planning (VSP) has been rapidly adopted as a part of reconstructive surgeon's armamentarium. VSP allows reconstructive surgeons to simulate resection, plan osteotomies, and design custom plates. These unique advantages have been especially beneficial for head and neck reconstructive surgeons as there is small room for error and high technical demand in head and neck reconstruction. Despite its popularity, most surgeons have limited experience in using VSP for orbito-maxillary reconstruction as tumors that involve the midface are relatively rare compared with other head and neck oncologic defects. In our institution, we routinely use VSP for orbito-maxillary reconstruction using free fibula flap to provide support for orbit, to restore normal dental occlusion, and to restore midface projection. In this chapter, we will discuss the role of virtual surgical planning and our algorithmic approach of performing orbito-maxillary reconstruction using free tissue transfer.

Quality of life in patients with cancer-related Brown IIb maxillary defect: A comparison between conventional obturation rehabilitation and submental flap reconstruction

OBJECTIVES

The purpose of this retrospective study was to compare the differences in quality of life (QOL) outcomes between the conventional obturator prostheses (COP) and the pedicled submental artery island flap (SAIF) in the reconstruction of Brown IIb maxillary defects.

MATERIALS AND METHODS

The QOL of 116 eligible patients who had a lapse ≥ 12 months after the cancer-related maxilla ablation was evaluated by the University of Washington quality of life scale (UW-QOL), Performance Status Scale for Head and Neck (PSS-HN), and Obturator Functioning Scale (OFS).

RESULTS

Patients in the SAIF group reported statistically and clinically significant higher overall QOL scores but lower chewing scores in the UW-QOL scale when compared with those in the COP group (P < 0.05). Clinically significantly higher scores were also observed in the recreation and anxiety domains in the UW-QOL scale for the SAIF group, but there was no statistical significances. The COP group reported more complaints about the nasal leakage when swallowing and the shape of the upper lip, and had a stronger willingness to avoid family or social events in the OFS (P < 0.05).

CONCLUSIONS

For patients with Brown IIb defects, SAIF reconstruction can achieve reduced nasal leakage when swallowing, improved upper-lip contour, increased social activity, and superior overall QOL than COP. The inferior chewing function in the SAIF group indicated the need for dental rehabilitation with a conventional denture or osseointegrated implants.

Fully digital workflow for the design and manufacture of prostheses for maxillectomy defects

A fully digital workflow for the design and manufacture of prostheses for maxillectomy defects was described. Three-dimensional images from spiral computed tomography and intraoral scanning were used to generate a three-dimensional digital cast of a maxillectomy defect. The obturator prosthesis was then designed on the digital cast by combining dental computer-aided design and reverse engineering software programs. The prosthesis was subsequently milled from polyetheretherketone or three-dimensional-printed from polylactic acid.

Mastication in maxillectomy patients: A comparison between reconstructed maxillae and implant supported obturators: A cross-sectional study

OBJECTIVE

The aim of this study was to compare masticatory performance and patient reported eating ability of maxillectomy patients with implant-supported obturators and patients with surgically reconstructed maxillae.

METHODS

This cross-sectional study was conducted at the University of Alberta, Edmonton, Canada and at Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands. Eleven surgically reconstructed maxillectomy patients have been included at University of Alberta and nine implant-supported obturator patients at MUMC+. The mixing ability test (MAT) was used to measure masticatory performance. In addition, the oral health related quality of life (OHRQoL) was measured with shortened versions of the oral health impact profile (OHIP) questionnaire. Values of the implant-supported obturator group versus the surgical reconstruction group were compared with independent t-tests in case of normal distribution, otherwise the Mann-Whitney U test was applied.

RESULTS

Patients with reconstructed maxillae and patients with implant-supported obturator prostheses had similar mean mixing ability indices (18.20 ± 2.38 resp. 18.66 ± 1.37; P = .614). The seven OHRQoL questions also showed no differences in masticatory ability between the two groups.

CONCLUSION

With caution, the results of this study seem to confirm earlier results that implant-supported obturation is a good alternative to surgical reconstruction for all Class II maxillary defects. With both techniques, the masticatory performance is sufficiently restored, with careful planning being highly desirable.