Comprehensive approach to functional palatomaxillary reconstruction using regional and free tissue transfer: Report of reconstructive and prosthodontic outcomes of 140 patients

Retention of implant retained obturator using two implant placement configurations for maxillectomy cases: in-vitro study

BACKGROUND

Implant-retained obturators for maxillectomy cases have several advantages over traditional obturators but prosthetic design for specific conditions after maxillary resection has several challenges and the appropriate implant placement configuration is essential for improving retention and the stability of the implant-retained obturator.

OBJECTIVES

The present study aimed to assess the retention force of using linear and nonlinear implant placement configurations using ball and socket attachment in implant-retained obturators at the initial retention and after simulation of six months of use.

MATERIALS AND METHODS

Two identical epoxy resin maxillary models of a completely edentulous unilateral maxillary defect (Brown's class IIb) were used for implant placement, in the first model three implants were arranged with linear placement configuration, and in the second model three implants were arranged in nonlinear placement configuration. For proper sample sizing, 26 models and obturator were used. Two equal groups of obturators (13 for each group) were constructed, each with a different implant placement configuration. Both groups used the same attachment design (a non-splinted ball attachment). Using a cyclic loading machine that served as a dental insertion and removal simulator, each study group was subjected to 500 tension-compression cycles simulating 6 months of use. Using the universal testing machine, each obturator was removed at a speed of 50 mm/min for the crosshead. peak load to dislodgement was measured at the initial retention and after the simulations of six months of use. Data were analyzed using independent and paired t-tests while percent change was analyzed using the Mann Whitney U test.

RESULTS

There were a statistically significant differences in retention between the nonlinear implant placement configuration for Brown's class IIb maxillectomy and the linear implant placement configuration at initial retention evaluation with p-value of < 0.0001 and after simulation of six months of usage with p-value of < 0.0001 Also, after simulation of 6 months of use group I lose - 24.87 (10.16) % of its retention while group II lose - 17.49 (7.78) %.

CONCLUSIONS

Non-linear implant placement is more retentive at the initial retention and after simulation of six months of use than linear and loses less retention after usage.

Modern Oncologic Maxillary Reconstruction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: (1) Have a broad understanding of the oncological principles relating to cancers involving the maxilla. (2) Define anatomically the various types of maxillectomy defects and their associated morbidity. (3) Understand the goals and principles of maxillary reconstruction. (4) Demonstrate an understanding of the strengths, limitations, and alternative reconstructive options for the various types of maxillectomy defects.

SUMMARY

Reconstruction of the maxilla following cancer resection has evolved over the past decade. Underpinned by advances in virtual surgery technology and an increased focus on dental rehabilitation, more sophisticated workflows using free bone flaps have become more commonplace. There are few reconstructions anywhere in the body that require the restoration of similarly intricate bone and soft-tissue relations with implications for both form and function, like the maxilla. Success demands careful anatomical definition of the defect, an understanding of the goals and principles of reconstruction, and the understanding of relative strengths and limitations of the various reconstructive options. Equally, as no one technique is without shortcomings and maxillary surgery can be associated with a significant complication profile, it is just as important to match the patient and oncologic context to the reconstruction. This article is intended to provide the reader with a broad overview of these core factors.

Retrospective study of the deep circumflex iliac artery flap and the vascularized fibula free flap for maxillary defect repair

OBJECTIVES

The deep circumflex iliac artery flap (DCIA) and vascularized fibular free flap (FFF) are mainstay flaps for maxillary defect reconstruction. This study compared the functional outcomes and success rates of these flaps to provide midface reconstruction strategies.

MATERIALS AND METHODS

Maxillary defects reconstructed with DCIA or FFF at the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology between May 2016 and May 2023 were retrospectively analyzed. The length, width, and height of the grafted bone segments; intermaxillary distance; buttress reconstruction rate (BRR); dental arch reconstruction rate (DAR); success rate; and dental implantation rate were compared.

RESULTS

The DCIA and FFF groups had 33 and 27 patients, respectively. Success rate in the DCIA group was 93.94 % and 100 % in the FFF group. The DCIA length was less than that of FFF; however, the width and height were significantly larger. 87.10 % of cases in the DCIA group were classified as Brown class b and c, 51.85 % of cases in the FFF group were classified as Brown class d. The average BRR in the DCIA group was 69.89 % ± 16.05 %, which was significantly higher than that in the FFF group. A total of 38.7 % and 11.1 % patients in the DCIA and FFF groups, respectively, had completed implantation.

CONCLUSION

DCIA has a greater width and height, and is more suitable for repairing Brown class b and c defects, providing sufficient bone for implantation, while the FFF is longer and more suitable for Brown class d defect reconstruction.

Single-stage computer-assisted approach for tumour resection and functional restoration of Brown class III maxillary defects-titanium mesh and zygomatic implants combined with vascularized anterolateral thigh flap

The functional restoration of Brown class III maxillary defects is a challenging endeavour in oral and maxillofacial surgery. Conventional reconstruction techniques with osseous free flaps have certain limitations, such as the need for multiple operations and greater patient morbidity. This study introduces a single-stage computer-assisted approach for tumour resection and functional restoration of these defects using titanium mesh, zygomatic implants, and a vascularized anterolateral thigh flap (ALTF). Virtual surgical planning was used to simulate tumour resection, titanium mesh placement, and zygomatic implant insertion. Surgery was performed under the guidance of mixed reality and surgical navigation. The tumour was resected by total hemimaxillectomy, and the reconstruction was performed using a pre-bent patient-specific titanium mesh for the orbital floor and two zygomatic implants placed and exposed through tunnels in an ALTF. The ALTF survived without any perioperative complications. A fixed prosthesis with built-in titanium frame was delivered 4 months postoperatively. At the 1-year follow-up, there was no tumour recurrence, the implants were osseointegrated, and aesthetics and masticatory function were satisfactory. An occlusal force of 155 N was attained on the reconstructed side, compared to 127 N on the non-surgical side.

Advances in Microvascular Reconstruction of the Orbit and Beyond: Considerations and a Checklist for Decision-Making

This paper aims to discuss the microvascular reconstruction of the orbit and adjacent regions and to propose a checklist to aid the reconstructive surgeon in this challenging undertaking. The discussion is based on a literature review that includes 32 retrospective case series, 5 case reports published in the last 34 years in PubMed, and 3 textbook chapters. Additionally, it relies on the senior author's expertise, described in a case series, and two case reports published elsewhere. Classifications and treatment algorithms on microvascular orbit reconstruction generally disregard patient-related factors. A more holistic approach can be advantageous: patient-related factors, such as age, comorbidities, prognosis, previous interventions, radiotherapy, and the wish for maximal dental rehabilitation and a prosthetic eye, have the same importance as defect-related considerations and can inform the choice of a reconstructive option. In this manuscript, we examine defect- and patient-related factors and new technologies, provide a checklist, and examine future directions. The checklist is intended as a tool to aid in the decision-making process when reconstructing the orbital region with microvascular flaps.

The Implant-borne Articulation Splint in Fibula Free Flap Mandibular Reconstruction: A Technical Note

Computer-aided design and computer-aided manufacturing and digitally simulated surgeries have revolutionized maxillomandibular reconstruction. In particular, this technology has increased the accuracy and facilitated the process of dental implantation in fibula free flaps. Despite the efficacy of virtual planning, there is a minor degree of translational difference between digital and intraoperative measurements, which may affect the precision of implant and fibula orientations. This is especially concerning during the last stage of fibula insetting, where the graft segments have the potential to roll, yaw, or pitch. The objective of this study is to describe an advanced prosthodontic technique that ensures the fibula grafts and implants remain in a restorable position during final insetting. We describe the technique and workflow of the implant-borne articulation splint through a case presentation and demonstrate results at 4 months postoperative and postradiotherapy. Given the degree of investment placed in virtual planning, free flap reconstruction, and endosteal implants, a technique that ensures optimal restorability of each implant is pivotal. Larger studies are still required to fully elucidate the cost-effectiveness and long-term results of the implant-borne articulation splint.

Long-term survival of implant-based oral rehabilitation following maxillofacial reconstruction with vascularized bone flap

Aim

The aim of the study was to assess the 5-year cumulative survival rate of implant-based dental rehabilitation following maxillofacial reconstruction with a vascularized bone flap and to investigate the potential risk factors which might influence the survival rate.

Materials and methods

A retrospective cohort study was designed. Inclusion criteria involved 18 years old or above patients with the availability of clinical and radiological data and a minimum follow-up 1 year following implant placement. The cumulative survival rate was analyzed by Kaplan–Meier curves and the influential risk factors were assessed using univariate log-rank tests and multivariable Cox-regression analysis.

Results

151 implants were assessed in 40 patients with a mean age of 56.43 ± 15.28 years at the time of implantation. The mean number of implants placed per patient was 3.8 ± 1.3 with a follow-up period of 50.0 ± 32.0 months. The cumulative survival at 1-, 2- and 5-years was 96%, 87%, and 81%. Patients with systemic diseases (HR = 3.75, 95% CI 1.65–8.52; p = 0.002), irradiated flap (HR = 2.27, 95% CI 1.00–5.17; p = 0.05) and poor oral hygiene (HR = 11.67; 95% CI 4.56–29.88; p < 0.0001) were at a significantly higher risk of implant failure.

Conclusion

The cumulative implant survival rate was highest at 1st year followed by 2nd and 5th year, indicating that the risk of implant failure increased over time. Risk indicators that seem to be detrimental to long-term survival include poor oral hygiene, irradiated flap and systemic diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40729-022-00413-7.

Implant-based dental rehabilitation in head and neck cancer patients after maxillofacial reconstruction with a free vascularized fibula flap: the effect on health-related quality of life

PURPOSE

To evaluate the effect of implant-based dental rehabilitation (IDR) on health-related quality of life (HRQoL) in head and neck cancer (HNC) patients after reconstruction with a free vascularized fibula flap (FFF).

METHODS

Eligible patients were identified by retrospectively reviewing the medical records of patients treated in Amsterdam UMC-VUmc. HRQoL data were used from OncoQuest, a hospital-based system to collect patient-reported outcome measures in routine care. Data were used of the EORTC QLQ-C30 and QLQ-H&N 35 before FFF reconstruction (T₀) and after completing IDR (T₁). Data were statistically analysed with the chi-square test, independent samples t test and linear mixed models.

RESULTS

Out of 96 patients with maxillofacial FFF reconstruction between January 2006 and October 2017, 57 patients (19 with and 38 without IDR) had HRQoL data at T₀ and T₁. In the cross-sectional analysis, patients with IDR scored significantly better at T₀ and T₁ on several EORTC domains compared to the patients without IDR. Weight loss was significantly different in the within-subject analysis between T₀ and T₁ for patients with IDR (p = 0.011). However, there were no significant differences in the mean changes of all the EORTC QLQ-C30 and EORTC QLQ-H&N35 scores between the defined timepoints for patients with IDR compared to those without.

CONCLUSIONS

In this study, no differences were found in the course of HRQoL in HNC patients who had undergone IDR after maxillofacial FFF reconstruction, compared to those who had not. Patients should be preoperatively informed to have realistic expectations regarding the outcome of IDR.

Maxillary Sinus Floor Infiltration: Results From a Series of 118 Maxillary Sinus Cancers

OBJECTIVES/HYPOTHESIS

Maxillary cancers are rare and aggressive tumors, which can spread beyond the sinus bony walls. Preoperative assessment of infiltration of maxillary sinus floor (MSF) is paramount for surgical planning, as palatomaxillary demolition significantly impacts patients' quality of life. This study investigates the challenges involved in the preoperative and intraoperative evaluation of MSF infiltration and analyzes its prognostic relevance.

STUDY DESIGN

Retrospective case series.

METHODS

A retrospective review of patients treated for sinonasal malignancies at a single Institution was performed. Patients receiving surgical-based treatment with curative intent for primary maxillary sinus cancers, between January 2000 and November 2019, were included.

RESULTS

A cohort of 118 patients was analyzed. By comparing intraoperative findings (endoscopic assessment and frozen sections) with preoperative radiological assessment, diagnostic changes with regard to MSF infiltration were found in 27.1% (32/118 cases). MSF infiltration negatively affected the prognosis in both univariate and multivariate analyses in the overall population. In the subgroup of pT1-T3 tumors, MSF infiltration was significantly associated with reduced overall (P = .012), disease-free (P = .011), and distant recurrence-free (P = .002) survival rates. Conversely, pT classification was not able to stratify patients according to prognosis, mainly because early-staged cancers (pT1-T2) with MSF infiltration showed reduced survival rates, similar to those observed in pT3 cancers.

CONCLUSIONS

Preoperative imaging should be integrated with intraoperative findings based on endoscopic inspection and frozen sections. Future studies are required to investigate the opportunity to incorporate MSF infiltration in the TNM staging system, considering its crucial role in defining the extent of surgery and its potential as prognosticator.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Immediate implant-retained prosthetic obturation after maxillectomy based on zygomatic implant placement by 3D-guided surgery: a cadaver study

Background

The aim of this study was to introduce a complete 3D workflow for immediate implant retained prosthetic rehabilitation following maxillectomy in cancer surgery. The workflow consists of a 3D virtual surgical planning for tumor resection, zygomatic implant placement, and for an implant-retained prosthetic-obturator to fit the planned outcome situation for immediate loading.

Materials and methods

In this study, 3D virtual surgical planning and resection of the maxilla, followed by guided placement of 10 zygomatic implants, using custom cutting and drill/placement-guides, was performed on 5 fresh frozen human cadavers. A preoperatively digitally designed and printed obturator prosthesis was placed and connected to the zygomatic implants. The accuracy of the implant positioning was obtained using 3D deviation analysis by merging the pre- and post-operative CT scan datasets.

Results

The preoperatively designed and manufactured obturator prostheses matched accurately the per-operative implant positions. All five obturators could be placed and fixated for immediate loading. The mean prosthetic point deviation on the cadavers was 1.03 ± 0.85 mm; the mean entry point deviation was 1.20 ± 0.62 mm; and the 3D angle deviation was 2.97 ± 1.44°.

Conclusions

It is possible to 3D plan and accurately execute the ablative surgery, placement of zygomatic implants, and immediate placement of an implant-retained obturator prosthesis with 3D virtual surgical planning.The next step is to apply the workflow in the operating room in patients planned for maxillectomy.

Maxillectomy defects: Virtually comparing fibular and scapular free flap reconstructions

BACKGROUND

This study virtually compares patient-specific fibular and scapular reconstructions for maxillectomies.

METHODS

Nine maxillectomy defects were created on 10 maxillas and virtually reconstructed with patient-specific fibulas and scapulas. Reconstructions were compared for restoring midface cephalometrics, dental implantability, and pedicle length.

RESULTS

Of 90 maxillectomy defects, the vertically oriented scapula provided improved orbital floor and maxillary height reconstructions (p < 0.001), albeit at the cost of dental implantability compared to the fibula (p < 0.001). In two defects crossing the midline, the fibula, allowing for more osteotomies, provided improved maxillary projection. In the remaining three defects crossing the midline, the horizontally oriented scapula was comparable to the fibula. Fibular and scapular reconstructions were amenable for dental implantation and had similar pedicle lengths, although favoring scapula in extensive defects.

CONCLUSION

Fibular and scapular reconstructions of maxillectomy defects provide unique strengths. This virtual analysis can guide a goal-oriented reconstruction based on defect type and patient-specific goals.

Postoperative Imaging Appearance of Iliac Crest Free Flaps Used for Palatomaxillary Reconstructions

The osteomyocutaneous iliac crest free flap is a reconstructive option for segmental mandibular or complex palatomaxillary defects. Familiarity with the radiographic appearance of free flaps such as the iliac crest is necessary for the postoperative evaluation of patients after mandibular, maxillary, or palatal reconstructions because it allows radiologists to properly monitor and interpret the appearance of the flap over time. This study presents a retrospective review of 5 patients who underwent palatomaxillary reconstruction with an iliac crest free flap at our institution. The imaging appearances of the 5 patients were analyzed to determine the key radiographic characteristics of a healthy and successful iliac crest free flap. Radiographic fluency with the imaging appearance of the iliac crest free flap, as well as the new anatomy of the region in the postoperative period, will allow for better interpretation of the flap appearance on imaging and will prevent false identification of tumor recurrence.

Prosthodontic rehabilitation of head and neck cancer patients-Challenges and new developments

Head and neck cancer treatment can severely alter oral function and aesthetics, and reduce quality of life. The role of maxillofacial prosthodontists in multidisciplinary treatment of head and neck cancer patients is essential when it comes to oral rehabilitation and its planning. This role should preferably start on the day of first intake. Maxillofacial prosthodontists should be involved in the care pathway to shape and outline the prosthetic and dental rehabilitation in line with the reconstructive surgical options. With the progress of three‐dimensional technology, the pretreatment insight in overall prognosis and possibilities of surgical and/or prosthetic rehabilitation has tremendously increased. This increased insight has helped to improve quality of cancer care. This expert review addresses the involvement of maxillofacial prosthodontists in treatment planning, highlighting prosthodontic rehabilitation of head and neck cancer patients from start to finish.

Palatomaxillary Reconstruction: Fibula or Scapula

Palatomaxillary reconstruction presents a unique challenge for the reconstructive surgeon. The maxillofacial skeleton preserves critical aerodigestive functions-it provides a stable hard palate to support mastication and separate the nasal and oral cavities, and buttress support to provide adequate midface contour. Free tissue transfer has become a routine part of the reconstructive ladder in managing palatomaxillary defects. While there is a wide variety of options for bony reconstruction within the head and neck, the fibula and the scapula, and their variations, have become two of the most commonly used options for midface reconstruction. This review will discuss the advantages and disadvantages of both in specific regard to reconstruction of the palatomaxillary area.

Reconstructive and prosthodontic outcomes after multiple palatomaxillary reconstructions

OBJECTIVE

A subset of patients who undergo major palatomaxillary reconstruction do not initially achieve their intended oncologic and/or reconstructive goals and require additional surgery. We aim to detail the unique management considerations in this patient population.

METHODS

We performed a retrospective review of patients who underwent palatomaxillary reconstruction by the senior author (m.l.u.) between 1998 and 2016.

RESULTS

Twenty-one patients required multiple reconstructions. The median time to second reconstruction was 17 months. The most common reason for a second reconstruction was for recurrent disease (10 of 21), followed by functional/aesthetic reasons (7 of 21) and osteoradionecrosis (4 of 21). Four patients went on to have a third reconstruction, and two underwent a fourth. A total of 27 reconstructions were performed, consisting of 20 soft tissue free flaps, four vascularized bone free flaps, and three locoregional flaps.

CONCLUSION

This patient cohort represents unique oncologic and reconstructive challenges. With long-term follow-up, multiple reconstructions may be required to optimize oncologic and functional/aesthetic outcomes. This is the first series of its kind that details the reasons for, as well as the outcomes of, patients who required multiple reconstructive procedures following initial palatomaxillary reconstruction.

LEVEL OF EVIDENCE

2B Laryngoscope, 130:2349-2353, 2020.