Prosthodontic rehabilitation of oral function in head-neck cancer patients with dental implants placed simultaneously during ablative tumour surgery: an assessment of treatment outcomes and quality of life

Osseointegrated dental implants that will undergo radiotherapy. Does risk of osteoradionecrosis exist? A scoping review

OBJECTIVE

Given the absence of a standardized action protocol for treating patients with dental implants (DIs) who are subjected to radiotherapy (RT), we have conducted an extensive review and analysis of published literature on this subject. Our objective is to gain a comprehensive understanding of the impact of RT on the bone surrounding osseointegrated implants during and after treatment.

STUDY DESIGN

We conducted a literature review using PubMed (MEDLINE) to identify studies describing the effects of RT on preexisting osseointegrated and/or loaded DIs. Articles published between January 1963 and December 2023 were considered for inclusion.

RESULTS

A total of 1,126 articles were retrieved, 64 full articles were reviewed, and only 13 articles were included in this review upon meeting the criteria. A total of 667 patients and 2,409 implants were included. Osteoradionecrosis (ORN) was observed in approximately 19 implants following antineoplastic treatment.

CONCLUSIONS

The interaction between DIs and RT is a complex and multifaceted issue that requires further research and clinical guidance. Although certain studies indicate a possible connection between DIs, radiation, and ORN risk, the precise relationship remains unclear. Factors such as radiation dosage, implant characteristics, material, and timing of placement significantly influence this association.

One-stage prosthodontically driven jaw reconstruction in patients with benign and malignant pathologies: A 7- to 11-year cohort study

OBJECTIVES

One stage functional jaw reconstruction is defined as the resection and reconstruction of segmental defects in conjunction with the placement of dental implants in an ideal prosthetic position and loaded with a provisional restoration, during one surgical procedure. The aim of the study is to describe clinical outcomes of patients who underwent one stage functional jaw reconstruction.

METHODS

Patients who underwent one-stage functional jaw reconstruction, from January 2013 to March 2016 were recalled in 2022 and 2023. Planning and execution for the reconstruction utilized either analogue or digital techniques. Outcome parameters recorded were treatment-related outcomes at patient level, implant-related outcomes and patient-reported outcome measures.

RESULTS

Eighteen patients underwent one-stage jaw reconstruction with a total of 57 implants. Four patients had maxillary and 14 had mandibular reconstructions. Ten patients underwent postoperative radiotherapy. Ten patients were planned using analogue and eight by digital planning. Three patients had partial flap necrosis, three patients had plate fractures, implant loss was seen in one patient and four patients died during the period. A functional prosthesis was provided in 16 out of the 18 patients.

CONCLUSION

One-stage functional jaw reconstruction is a predictable method for providing rehabilitation with successful outcomes at 7-11 years. However, caution should be exercised when the treatment modality is carried out in patients with malignant pathologies who have undergone radiotherapy.

Long-Term Survival of Dental Implants in Irradiated Patients

The surgical ablation of head and neck cancer followed by radiotherapy often leads to unfavorable functional and aesthetic outcomes. Studies have demonstrated that these outcomes can significantly impact quality of life. Dental implants play a crucial role in rehabilitation by facilitating the use of suprastructures and obturators. However, the long-term survival of dental implants in patients who have undergone radiotherapy remains uncertain, raising several questions. These include determining the optimal timing for dental implantation (before or after radiotherapy), identifying the radiotherapy threshold for implant loss, and considering the role of hyperbaric oxygen therapy. These and other related concerns will be addressed in the following article.

Free flap jaw reconstruction with dental implantation: A single-institution experience

BACKGROUND

We sought to review our institution's experience with dental implant placement in free flap jaw reconstruction to determine factors impacting restoration of dental occlusion.

METHODS

Exactly 48 patients underwent free flap jaw reconstruction with or without dental restoration from 2017 to 2022. Primary outcome was achievement of restored dental occlusion after jaw free flap reconstruction.

RESULTS

A total of 48 patients with a mean age of 59.8 ± 16.4 years underwent jaw reconstruction from 2017 to 2022. Ten patients (20.8%) received osteointegrated dental implants. Two patients received a temporary dental prosthesis, 12 ± 4 months after initial reconstruction. Three patients received a final prosthesis, with a mean time to final prosthesis of 17.7 ± 12.4 months. Five patients did not receive any prosthesis despite placement of implants.

CONCLUSION

A minority of patients received dental implant placement with free flap jaw reconstruction and only a small subset of these received a definitive dental prosthesis.

Prosthetic rehabilitation in patients with jaw reconstruction by fibula free flap: A systematic review

This systematic review aimed to evaluate the dental prosthetic rehabilitation (DPR) in patients after jaw reconstruction with fibula free flap. Four databases were searched from January 2000 to January 2023. Of the 2507 studies identified, 36 observational studies were included. Cancer was the most common surgical indications for jawbone resection with 58.3 % of cases followed by benign tumours which representing 24 %. The DPR rate was estimated at 51.6 % across the studies (ranging from 38 % to 55 % depending on the benign or malignant nature of the tumors). Implant-supported prostheses represented 58.9 % of cases of which 66.9 % were fixed and 33.1 % were implant-stabilized overdentures. Virtual surgical planning (VSP) was used in 20 % of studies and aimed to improve the position of the grafted fibula, quality, and aesthetics of DPR and to decrease ischemia and the operating time. One in two authors performed DPR 12 months after jaw reconstruction. If implant survival rate reached 93 % in non-irradiated fibula, it fell to 38 %, 55 %, and 77 % if implantation occurred in the 12, 17, and 24 months after radiotherapy, respectively. Various parameters should be better investigated in further studies including the typology of the prostheses (implant-supported vs removable), the use of VSP, and the optimal time for DPR taking into account the characteristics of the tumor, the size of bone defect, and the need for external irradiation therapy.

Implant-supported prostheses in patients with special needs: A systematic literature review of protocols and outcomes

STATEMENT OF PROBLEM

Implant-supported prostheses for individuals with special needs have been considered high-risk because of the prevalence of poor oral hygiene and parafunction in this population; however, systematic evidence on protocols and outcomes is scarce.

PURPOSE

The purpose of this systematic review was to summarize implant procedures and outcomes for the special needs population.

MATERIAL AND METHODS

A systematic literature review was conducted using PubMed, Embase, and Scopus databases in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodological framework. Data collected included patient information, location and number of implants, surgical and prosthetic procedures, behavior support techniques, postoperative follow-up, complications, and criteria for outcome assessment. Survival rates were pooled for quantitative analysis, and a separate analysis pooling data from groups of special needs patients that present similar risks was undertaken.

RESULTS

The qualitative analysis included 79 studies involving 759 patients and 2269 implants. The quantitative analysis included 65 studies concerning 666 patients with special needs and 1886 implants. The overall weighted implant survival rate was 95.4%, with a mean follow-up duration of 40.7 ±29.5 months.

CONCLUSIONS

In individuals with special needs considered suitable for implant-supported prostheses by their clinician, implant survival rates were similar to those reported in the general population. (J Prosthet Dent xxxx;xxx:xxx-xxx).

Dental implants in patients with head and neck cancer-A systematic review and meta-analysis of the influence of radiotherapy on implant survival

PURPOSE

The purpose of this meta-analysis was to compare implant survival in irradiated and non-irradiated bone and to investigate potential risk factors for implant therapy in oral cancer patients.

MATERIAL AND METHODS

An extensive search in the electronic databases of the National Library of Medicine was performed. Systematic review and meta-analysis were conducted according to PRISMA statement. The meta-analysis was performed for studies with a mean follow-up of at least three and five years, respectively.

RESULTS

The systematic review resulted in a mean overall implant survival of 87.8% (34%-100%). The meta-analysis revealed a significantly higher rate of implant failure in irradiated bone compared to non-irradiated bone (p < .00001, OR 1.97, CI [1.63, 2.37]). The studies also showed that implants placed into irradiated grafted bone were more likely to fail than those in irradiated native bone (p < .0001, OR 2.26, CI [1.50, 3.40]).

CONCLUSION

Even though overall implant survival was high, radiotherapy proves to be a significant risk factor for implant loss. Augmentation procedures may also increase the risk of an adverse outcome, especially in combination with radiotherapy.

CLINICAL RELEVANCE

The treatment of patients receiving radiotherapy of any form requires precise individual planning and a close aftercare. Implants should be placed in local bone rather than in bone grafts, if possible.

A Simplified Approach to Jaw-in-a-Day Using a Preassembled Prosthesis: Lowering the Barrier to Entry

Fibula flap reconstruction with primary dental implant placement has been established as a successful procedure for composite mandibular defects. When using virtual surgical planning, these techniques typically require additional personnel and materials preoperatively and intraoperatively to fabricate occlusal-based guidance and prosthesis. The authors present a technique utilizing a custom-made implant-supported prosthesis completed before surgery that greatly reduces lead time and needed resources. The authors follow the established workflow of segmental mandibulectomy and fibula flap reconstruction using premanufactured cutting guides and placement of dental implants. Cylindrical holes along the implant axes are included in the printed surgical model provided by the guide manufacturer. Acrylic resin and abutments are added to the model to a positioning stent for use during surgery that does not require intraoperative modification before fibula inset. This ensures optimal position for facial esthetics and fixed dental rehabilitation. The presented technique uses printed models already provided by the guide manufacturer, reducing preparation time and requiring fewer personnel and materials intraoperatively. This is an approach to the jaw-in-a-day procedure with a lower barrier to entry that may be used by new craniofacial teams.

Health-related quality of life in maxillectomy patients undergoing dentoalveolar rehabilitation

OBJECTIVES

Surgical resection of the maxilla impairs aesthetics, speech, swallowing, and mastication. Maxillary reconstruction is increasingly performed with virtual surgical planning (VSP) to enhance functional dental rehabilitation with a conventional denture or osseointegrated implants. The aim of this study was to determine whether dental status and VSP is associated with health-related quality of life (HRQOL) and function in patients who have undergone maxillectomy.

MATERIALS AND METHODS

A cross-sectional study was conducted among patients who underwent free flap reconstruction or obturation of the maxilla between July 2009 and December 2020. The FACE-Q Head and Neck Cancer (FACE-Q) module, M.D. Anderson Dysphagia Inventory (MDADI), and Speech Handicap Index (SHI) were used to evaluate HRQOL.

RESULTS

Forty-three patients (response rate 59%) completed questionnaires and 48% underwent dental rehabilitation. In Okay Class II and III defects, adjusting for the effect of radiotherapy and time from surgery, there was a positive association between denture status and FACE-Q smiling (p = 0.020), eating (p = 0.012), smiling (p = 0.015), and MDADI global (p = 0.015), emotional (p = 0.027), functional (p = 0.028), and composite (p = 0.029) scores. VSP was associated with FACE-Q swallowing (p = 0.005), drooling (p = 0.030), eating (p = 0.008), smiling (p = 0.021), MDADI global (p = 0.017), emotional (p = 0.041), functional (p = 0.040), composite (p = 0.038), and SHI total scores (p = 0.042).

CONCLUSIONS

Dentoalveolar rehabilitation and VSP were associated with higher HRQOL scores relating to eating and drinking, smiling, and speaking.

Computer-Assisted Dental Implant Placement Following Free Flap Reconstruction: Virtual Planning, CAD/CAM Templates, Dynamic Navigation and Augmented Reality

Image-guided surgery, prosthetic-based virtual planning, 3D printing, and CAD/CAM technology are changing head and neck ablative and reconstructive surgical oncology. Due to quality-of-life improvement, dental implant rehabilitation could be considered in every patient treated with curative intent. Accurate implant placement is mandatory for prosthesis long-term stability and success in oncologic patients. We present a prospective study, with a novel workflow, comprising 11 patients reconstructed with free flaps and 56 osseointegrated implants placed in bone flaps or remnant jaws (iliac crest, fibula, radial forearm, anterolateral thigh). Starting from CT data and jaw plaster model scanning, virtual dental prosthesis was designed. Then prosthetically driven dental implacement was also virtually planned and transferred to the patient by means of intraoperative infrared optical navigation (first four patients), and a combination of conventional static teeth supported 3D-printed acrylic guide stent, intraoperative dynamic navigation, and augmented reality for final intraoperative verification (last 7 patients). Coronal, apical, and angular deviation between virtual surgical planning and final guided intraoperative position was measured on each implant. There is a clear learning curve for surgeons when applying guided methods. Initial only-navigated cases achieved low accuracy but were comparable to non-guided freehand positioning due to jig registration instability. Subsequent dynamic navigation cases combining highly stable acrylic static guides as reference and registration markers result in the highest accuracy with a 1–1.5-mm deviation at the insertion point. Smartphone-based augmented reality visualization is a valuable tool for intraoperative visualization and final verification, although it is still a difficult technique for guiding surgery. A fixed screw-retained ideal dental prosthesis was achieved in every case as virtually planned. Implant placement, the final step in free flap oncological reconstruction, could be accurately planned and placed with image-guided surgery, 3D printing, and CAD/CAM technology. The learning curve could be overcome with preclinical laboratory training, but virtually designed and 3D-printed tracer registration stability is crucial for accurate and predictable results. Applying these concepts to our difficult oncologic patient subgroup with deep anatomic alterations ended in comparable results as those reported in non-oncologic patients.

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.

Survival of dental implants and occurrence of osteoradionecrosis in irradiated head and neck cancer patients: a systematic review and meta-analysis

OBJECTIVES

This systematic review assesses dental implant survival, calculates the incidence rate of osteoradionecrosis, and evaluates risk factors in irradiated head and neck cancer patients.

MATERIALS AND METHODS

Various databases (e.g., Medline/Embase using Ovid) and gray literature platforms were searched using a combination of keywords and subject headings. When appropriate, meta-analysis was carried out using a random effects model. Otherwise, pooled analysis was applied.

RESULTS

A total of 425 of the 660 included patients received radiotherapy. In total, 2602 dental implants were placed, and 1637 were placed in irradiated patients. Implant survival after an average follow-up of 37.7 months was 97% (5% confidence interval, CI 95.2%, 95% CI 98.3%) in nonirradiated patients and 91.9% (5% CI 87.7%, 95% CI: 95.3%) after an average follow-up of 39.8 months in irradiated patients. Osteoradionecrosis occurred in 11 cases, leading to an incidence of 3% (5% CI 1.6%, 95% CI 4.9%). The main factors impacting implant survival were radiation and grafting status, while factors influencing osteoradionecrosis could not be determined using meta-analysis.

CONCLUSION

Our data show that implant survival in irradiated patients is lower than in nonirradiated patients, and osteoradionecrosis is-while rare-a serious complication that any OMF surgeon should be prepared for. The key to success could be a standardized patient selection and therapy to improve the standard of care, reduce risks and shorten treatment time.

CLINICAL RELEVANCE

Our analysis provides further evidence that implant placement is a feasible treatment option in irradiated head and neck cancer patients with diminished oral function and good long-term cancer prognosis.

Health-Related Quality of Life in Oral Cancer Patients: Scoping Review and Critical Appraisal of Investigated Determinants

Simple Summary

Oral cancer may strongly impair patients’ quality of life. Huge efforts have been made during recent decades in trying to improve the treatment outcomes in terms of patients’ survival, self-perception, and satisfaction. Consequently, the investigation into health-related quality of life (HRQOL) became an established and worldwide practice. Hundreds of studies tried to clarify which could be the most important variables that impact HRQOL in head and neck cancer patients. However, such a complex topic may be influenced by a multitude of interconnected aspects and several controversies were reported. In this study the current literature was reviewed to identify all those possible sources of bias that may be encountered in trying to correlate HRQOL to patient-specific or disease/treatment-specific aspects. As a result, a list of recommendations was reported to enhance the evidence of future studies.

Abstract

Background: health-related quality of life (HRQOL) represents a secondary endpoint of medical interventions in oncological patients. Our aim was to highlight potential sources of bias that could be encountered when evaluating HRQOL in oral cancer patients. Methods: this review followed PRISMA-ScR recommendations. Participants: patients treated for oral cancer. Concept: HRQOL assessed by EORTC QLQ-C30 and QLQ-H&N35/QLQ-H&N43. A critical appraisal of included studies was performed to evaluate the accuracy of data stratification with respect to HRQOL determinants. Results: overall, 30 studies met the inclusion criteria, totaling 1833 patients. In total, 8 sociodemographic (SDG) and 15 disease/treatment-specific (DT) HRQOL determinants (independent variables) were identified. The mean number of the independent variables was 6.1 (SD, 4.3)—5.0 (SD, 4.0) DT-related and 1.1 (SD, 1.8) SDG-related variables per article. None of the included papers considered all the identified determinants simultaneously. Conclusions: a substantial lack of evidence regarding HRQOL determinants was demonstrated. This strongly weakens the reliability of the reported findings due to the challenging presence of baseline confounding, selection, and omitted variable biases. The proposed approach recommends the use of further evaluation tools that gather more variables in a single score together with a selection of more homogeneous, reproducible, and comparable cohorts based on the identified baseline confounding.

Clinical long-term and patient-reported outcomes of dental implants in oral cancer patients

BACKGROUND AND PURPOSE

The aim of this clinical study was to investigate the clinical long-term and patient-reported outcome of dental implants in patients with oral cancer. In addition, analysis of the influence of radiation therapy, timing of implant insertion, and augmentation procedures on implant survival was performed.

MATERIAL AND METHODS

This retrospective study investigated the clinical outcome of 711 dental implants in 164 oral cancer patients, inserted by experienced surgeons of the Department of Oral and Maxillofacial Surgery, University Medical Center Mainz, Germany. Oral health-related quality of life (OHRQoL) was evaluated.

RESULTS

Cumulative 5-year and 10-year implant survival rates for all included implants were 87.3% and 80.0%. Implants placed straight after ablative surgery (primary implant placement) and implants placed after completing the oncologic treatment (secondary implant placement) showed a comparable implant survival (92.5% vs. 89.5%; p = 0.635). Irradiation therapy had no significant influence on implant survival of secondary placed implants (p = 0.929). However, regarding implant site (native bone vs. augmented bone) and radiation therapy (non-irradiated bone vs. irradiated bone), implants inserted in irradiated bone that received augmentation procedures showed a statistically significant lower implant survival (p < 0.001). Patients reported a distinct improvement in OHRQoL.

CONCLUSIONS

Promising long-term survival rates of dental implants in patients after treatment of oral cancer were seen. In addition, patients benefit in form of an improved OHRQoL. However, bone augmentation procedures in irradiated bone may result in an impaired implants' prognosis.

Immediate dental implant placement and restoration in the edentulous mandible in head and neck cancer patients: a systematic review and meta-analysis

PURPOSE OF REVIEW

Oral rehabilitation with dental implants in head and neck cancer (HNC) patients is challenging. After tooth removal prior to radiotherapy, immediate placement of dental implants during panendoscopy or surgery is thought to reduce the oral rehabilitation time improving patients' quality of life.

RECENT FINDINGS

There is lack of consensus on the timing of dental implant placement and loading protocols. The aim of this study was to perform a systematic review of the literature regarding the performance and survival rate of immediately inserted dental implants placed prior to radiotherapy. Of 1003 articles, 10 were finally included comparing immediate vs. delayed placement of implants and comparing the effect of radiotherapy on immediately placed implants. Meta-analysis demonstrated a slightly higher survival of immediately placed implants compared with postponed placed implants [risk ratio: 0.92, 95% confidence interval (95% CI): 0.48-1.78, P = 0.81, I2 = 0%]. The other meta-analysis comparing radiotherapy vs. nonradiotherapy showed a clearly better survival of immediately placed implants not having received radiotherapy (risk ratio: 5.02, 95% CI: 0.92-27.38, P = 0.10, I2  = 56%).

SUMMARY

Guidelines are recommended for immediate dental implant placement in the edentulous mandible in HNC patients prior to radiotherapy to allow homogeneity regarding the treatment protocols and thus comparison of treatment outcomes.

Outcomes of osseointegrated implants in patients with benign and malignant pathologies of the head and neck: a 10-year single-centre study

The surgical management of head and neck pathologies involving the maxilla and mandible results in significant functional and aesthetic deficits, and ultimately reduced quality of life. Composite free flaps used for reconstruction address many of these deficits and create a foundation for the use of osseointegrated implants to support prosthetic replacement of the dentition. There are few comparative studies examining outcomes of implants in native and reconstructed bone in head and neck cancer patients. The aim of this retrospective cohort study was to compare survival rates and the effects of risk factors between implants placed in native and reconstructed bone. The Kaplan-Meier method estimated cumulative 1- and 5-year implant survival rates of 99.5% and 95% for native bone and 96% and 88% for reconstructed bone. Multivariate Cox regression found an increased risk of implant failure in reconstructed bone (hazard ratio (HR) 9.9, 95% confidence interval (CI) 3.4-29.7, P<0.001). Subgroup analysis of the cohorts found an increased risk of failure in the reconstructed group associated with radiotherapy (HR 6.4, 95% CI 1.8-22.3, P=0.004), current smoking (HR 23.2, 95% CI 2.7-198.6, P=0.004), and previous smoking (HR 9.0, 95% CI 1.1-71.9, P=0.038). There was no effect in the native bone group. Implants placed into reconstructed bone had higher rates of failure, and smoking status and radiotherapy increased the risk of implant failure.

Immediate implant placement in edentulous oral cancer patients: a long-term retrospective analysis of 207 patients

Although the functional benefits of implants in the rehabilitation of edentulous cancer patients are well-known, most studies report on postponed implant placement. The outcome of immediate implant placement regarding successful rehabilitation, implant loading and survival is unclear. Two hundred and seven edentulous oral cancer patients that received implants during ablative surgery at the Radboud University Medical Centre between 2000 and 2011 were included. Data regarding the oncological treatment, implant placement, follow-up and prosthodontic rehabilitation were recorded retrospectively with a follow-up period of 5-17 years. Functioning implant-retained dentures were made in 73.9% of the patients. Of the surviving patients, 81.9% had functioning dentures after 2 years and 86.3% after 10 years. Patients with ASA score 1 and younger patients were rehabilitated more frequently. The median time of functioning denture placement was 336 days after surgery, with a negative influence of postoperative radiotherapy. Implant survival was 90.7%, and was lower when the implant was placed in a jaw involved in the tumour. Immediate implant placement during oral cancer surgery led to a high number of edentulous patients rehabilitated with implant-retained dentures, which are placed at an early time.

Systematic review of postoperative therapy for resected squamous cell carcinoma of the head and neck: Executive summary of the American Radium Society appropriate use criteria

BACKGROUND

The aims of this systematic review are to (a) evaluate the current literature on the impact of postoperative therapy for resected squamous cell carcinoma of the head and neck (SCCHN) on oncologic and non-oncologic outcomes and (b) identify the optimal evidence-based postoperative therapy recommendations for commonly encountered clinical scenarios.

METHODS

An analysis of the medical literature from peer-reviewed journals was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. Prospective studies and methodology-based systematic reviews and meta-analyses of postoperative therapy for SCCHN were identified by searching Medline (OVID) and EMBASE (Elsevier) using controlled vocabulary terms (ie, National Library of Medicine Medical Subject Headings [MeSH], EMTREE). Study screening and selection was performed with Covidence software and full-text review. The RAND/UCLA appropriateness method was used by the expert panel to rate the appropriate use of postoperative therapy, and the modified Delphi method was used to come to consensus.

RESULTS

A total of 5660 studies were identified and screened using the title and abstract, leading to 201 studies assessed for relevance using full-text review. After limitation to the eligibility criteria, 101 studies from 1977 to 2020 were identified, including 77 with oncologic endpoints and 24 with function and quality of life endpoints. All studies reported staging prior to the implementation of American Joint Committee on Cancer (AJCC-8).

CONCLUSIONS

Prospective clinical studies and systematic reviews identified through the PRISMA systematic review provided good evidence for consensus statements regarding the appropriate use of postoperative therapy for resected SCCHN. Further research is needed in domains where consensus by the expert panel could not be achieved for the appropriateness of specific postoperative therapeutic interventions.

Influence of implant-specific radiation doses on peri-implant hard and soft tissue: An observational pilot study

OBJECTIVES

The aim of this study was to investigate the influence of real implant-bed-specific radiation doses on peri-implant tissue health in head and neck cancer (HNC) patients after radiotherapy.

MATERIAL AND METHODS

Specific radiation doses in the area of 81 implants, in 15 irradiated HNC patients, were analyzed by matching data from the radiotherapy planning system with those of three-dimensional follow-up scans after implantation. Peri-implant bone resorption was measured radiographically after 1 and 3 years, and peri-implant tissue health was evaluated clinically. Individual parameters, such as age, gender, and localization, regarding the implant-specific radiation dose distribution were analyzed statistically.

RESULTS

The mean implant-bed-specific radiation dose was high, with 45.95 Gy to the mandible and 29.02 Gy to the maxilla, but significantly lower than the mean total dose to the tumor bed. Peri-implant bone resorption correlated with local inflammation and plaque. After 1 year, women temporarily showed significantly more bone loss than men and implant-specific radiation dose had a significant impact on peri-implant bone loss after 3 years.

CONCLUSIONS

The presented method is a feasible option to define precise implant-bed-specific radiation doses for research or treatment planning purposes. Implant-based dental restoration after radiotherapy is a relatively safe procedure, but a negative radiation dose-dependent long-term effect on peri-implant bone resorption calls for interdisciplinary cooperation between surgeons and radio-oncologists to define high-risk areas.

Short-Term Outcomes following Virtual Surgery-Assisted Immediate Dental Implant Placement in Free Fibula Flaps for Oncologic Mandibular Reconstruction

BACKGROUND

Despite reports demonstrating feasibility of immediate dental implant placement in mandibular reconstruction with free fibula flaps for benign disease, this practice is not routinely used in the oncologic setting. The authors aim to demonstrate the safety of immediate dental implant placement for oncologic mandible reconstruction.

METHODS

In 2017, the authors' center began immediate dental implant placement in free fibula flaps for oncologic patients undergoing mandibulectomy reconstruction. Immediate dental implant placement patients were compared to a historical cohort also reconstructed with computer-aided design and manufacturing technology beginning in 2011 (n = 34) as a noninferiority study design. Primary outcomes of interest included 90-day complications, time to radiotherapy, and time to and number of patients achieving dental restoration.

RESULTS

Sixty-one patients underwent free fibula flaps following mandibulectomy using computer-aided design and manufacturing. Seventy-two dental implants were placed in the immediate dental implant placement cohort (n = 27). No differences were noted in major or minor 90-day complications between groups (p > 0.05). Radiotherapy was required in 55 percent in the immediate dental implant placement cohort versus 62 percent in the historical cohort, with no significant difference in time to radiotherapy (67.6 days versus 62.2 days, respectively). One dental implant was removed for nonosseointegration noted during vestibuloplasty. Fourteen (51.8 percent) immediate dental implant patients had complete dental restoration at 90 days compared with none in the historical cohort (p < 0.05).

CONCLUSIONS

Immediate dental implant placement is a safe procedure with an unchanged short-term complication profile and no delay in radiotherapy initiation. Patients undergoing immediate dental implant placement are more likely to complete full dental rehabilitation. Long-term and health-related quality-of-life outcomes remain to be determined.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Dental Implant Survival in Vascularized Bone Flaps: A Systematic Review and Meta-Analysis

BACKGROUND

Maxillofacial reconstruction with vascularized bone restores facial contour and provides structural support and a foundation for dental rehabilitation. Routine implant placement in such cases, however, remains uncommon. This study aims to determine dental implant survival in patients undergoing vascularized maxillary or mandibular reconstruction through a systematic review of the literature.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the literature was queried for implant placement in reconstructed jaws using Medical Subject Headings terms on PubMed, Embase, and Cochrane platforms. Weighted implant survivals were calculated for the entire cohort and subcohorts stratified by radiotherapy. Meta-analyses were performed to estimate effect of radiation on implant osseointegration.

RESULTS

Of 3965 publications identified, 42 were reviewed, including 1084 patients with 3636 dental implants. Weighted implant survival was 92.2 percent at a median follow-up of 36 months. Survival was 97.0 percent in 269 implants placed immediately in 60 patients versus 89.9 percent in 1897 delayed implants placed in 597 patients, with follow-up of 14 and 40 months, respectively. Dental implants without radiotherapy exposure had better survival than those exposed to radiation (95.3 versus 84.6 percent; p < 0.01) at a median follow-up of 36 months. Meta-analyses showed that radiation significantly increased the risk of implant failure (risk ratio, 4.74; p < 0.01) and suggested that implants placed before radiotherapy trended toward better survival (88.9 percent versus 83.4 percent, p = 0.07; risk ratio, 0.52; p = 0.14).

CONCLUSIONS

Overall implant survival was 92.2 percent; however, radiotherapy adversely impacted outcomes. Implants placed before radiotherapy may demonstrate superior survival than implants placed after.

Mandibular dental implant placement immediately after teeth removal in head and neck cancer patients

BACKGROUND

Little is known about immediate implant placement in head and neck cancer patients. We studied implant survival and functional outcomes of overdentures fabricated on implants placed immediately after removal of the lower dentition during ablative surgery or preceding primary radiotherapy (RT).

METHODS

Inclusion criteria were primary head and neck cancer, dentate lower jaw, and indication for removal of remaining teeth. Two implants to support a mandibular overdenture were placed immediately after extraction of the dentition during ablative surgery, or prior to starting primary radiotherapy. Standardized questionnaires and clinical assessments were conducted (median follow-up 18.5 months, IQR 13.3).

RESULTS

Fifty-eight implants were placed in 29 patients. Four implants were lost (implant survival rate 93.1%). In 9 patients, no functional overdenture could be made. All patients were satisfied with their dentures.

CONCLUSIONS

Combining dental implant placement with removal of remaining teeth preceding head neck oncology treatment results in a favorable treatment outcome.

Postimplantation radiation therapy in head and neck cancer patients: Literature review

There is no recommendation regarding the timing for implant surgery in patients with head and neck cancer (HNC) who require postoperative radiation therapy (RT). This systematic review focused on the literature about the outcomes of implants placed during ablative surgery in patients with HNC who underwent postoperative RT. Implants placed after radiation therapy and implants placed in reconstructed jaws were excluded. Four comparative studies involving 755 native mandible primary implants were analyzed. The survival rate with postimplantation RT was 89.6% vs 98.6% in patients with no additional radiation. The overall success of implant-retained overdenture in patients with RT performed postimplantation was 67.4% vs 93.1% in patients with implant surgery that was carried out 1 year after the completion of radiation therapy. Only five cases of osteoradionecrosis (ORN) of the jaw were reported. The outcomes for implant survival rates appear to be positive for irradiated implants.

Maxillofacial Rehabilitation With Zygomatic Implants in an Oncologic Patient: A Case Report

Tumor ablation results in significant sequelae in the appearance, function, and esthetics of a patient with cancer, especially resection for head and neck cancer. Reconstruction with local and microvascular flaps is a workable option; however, the esthetic results will occasionally be unfulfilling and inadequate for the rehabilitation of lost structures. Prosthetic rehabilitation with conventional and zygomatic implants can provide favorable and predictable long-term results. We report the clinical case of a 53-year-old female patient with adenoid cystic carcinoma (ACC). The treatment protocol included radical surgery, radiotherapy, and maxillofacial rehabilitation with conventional and zygomatic implants. Management of an ACC case requires a timely, radical, and multidisciplinary approach. In our patient, rehabilitation of masticatory function was accomplished in the immediate postoperative period and before radiotherapy. The rehabilitation of masticatory function improved the patient's systemic and nutritional status and her speech, with coverage of the esthetic defect. These outcomes reduced the psychological and emotional effects of tumor ablation.

Effects of ionizing irradiation and interface backscatter on human mesenchymal stem cells cultured on titanium surfaces

Radiotherapy to the head and neck region negatively influences the osseointegration and survival of dental implants. The effects of cobalt 60 (⁶⁰ Co) ionizing radiation and the impact of backscatter rays were investigated on human mesenchymal stem cells cultured on titanium surfaces. Bone marrow-derived human mesenchymal stem cells were seeded on titanium (Ti), fluoride-modified titanium (TiF), and tissue culture plastic. Cells were exposed to ionizing γ-radiation in single doses of 2, 6, or 10 Gy using a ⁶⁰ Co source. Density and distribution of cells were evaluated using confocal laser-scanning microscopy, 21 d post-irradiation. Lactate dehydrogenase concentration and the levels of total protein and cytokines/chemokines were measured in the cell-culture medium on days 1, 3, 7, 14, and 21 post-irradiation. Unirradiated cells were used as the control. Irradiation had no effect on cell viability, collagen and actin expression, or cell distribution, but induced an initial increase in the secretion of interleukin (IL)-6, IL-8, monocyte chemotactic protein 1 (MCP-1), and vascular endothelial growth factor (VEGF), followed by a decrease in secretion after 3 or 7 d. Irradiation resulted in secretion of a lower amount of all analytes examined compared with controls on day 21, irrespective of radiation dose and growth surface. Backscattering from titanium did not influence the cell response significantly, suggesting a clinical potential for achieving successful osseointegration of dental implants placed before radiotherapy.

A Comparison of Immediate and Delayed Dental Implant Placement in Head and Neck Surgery Patients

PURPOSE

Implant-supported dental prostheses offer numerous benefits for patients after ablative procedures of the head and neck region, including restoration of function, improved self-esteem and body satisfaction, and overall quality of life. Increased experience is emerging with immediate placement of implants at the time of ablative surgery compared with the traditional delayed approach. The authors sought to identify variables affecting survival of osseointegrated dental implants in such patients and to assess the impact of timing of implant insertion (immediate vs delayed) on the time until final prosthesis insertion.

MATERIALS AND METHODS

Implant survival was assessed based on different factors: immediate versus delayed implants, benign versus malignant disease, postoperative radiotherapy, smoking status, alcohol status, age, 1- versus 2-stage surgery, hyperbaric oxygen therapy, and implant placement into native bone versus into osseous free flap reconstruction. Time to final prosthesis insertion was compared between immediate and delayed implant placement.

RESULTS

The study included 20 patients who received a total of 102 implants (39 immediate, 63 delayed). There were 7 failed implants (overall survival, 93.14%). There was no statistically relevant difference in implant survival between any of the groups assessed. However, there was a significant decrease in time to final prosthesis insertion for those patients receiving immediate implants compared with those who underwent delayed implant placement (321 days; standard error, 46.5 vs 726 days; standard error, 45 days; P < .0001).

CONCLUSIONS

Immediate implant placement is an effective approach to the prosthetic rehabilitation of patients undergoing ablative procedures of the jaws, which shortens time to final prosthesis placement without adversely affecting overall implant survival.

[CAD/CAM Revolution in Craniofacial Reconstruction]

CAD/CAM Revolution in Craniofacial Reconstruction Abstract. The face is an important part of the personality and at the same time fulfils a variety of tasks. Aesthetics and function form a unique unit. The formation of the field of oral and maxillofacial surgery began in the first decades of the last century. It includes the prevention, diagnosis, therapy and rehabilitation of diseases, injuries, malformations and changes of the complex structures of the face, oral cavity, jaw and teeth. In the meantime, oral and maxillofacial surgery has arrived in the 21st century. Today's oral and maxillofacial surgery is a link between medicine and dentistry and a protagonist in the implementation of digital workflows in clinical care. Individual solutions with patient-specific implants are the rule, computer-assisted techniques support the surgeon in the planning and performing of surgical procedures. This article intends to give you an insight into how our patients benefit from advanced technologies.

Prosthetic rehabilitation for a patient treated for embryonal rhabdomyosarcoma

A female patient, now aged 17 years, was diagnosed with rhabdomyosarcoma (RMS) in the right pterygopalatine fossa when she was 3 years old. The RMS was successfully treated by excision, but the subsequent radiation and polychemotherapy resulted in the complete anesthesia of the distribution area of the right trigeminal nerve and loss of vision in the right eye. The patient also experienced pain in the mandibular joints and masticatory muscles. Panoramic radiographs displayed a multiple agenesia of the permanent teeth and underdeveloped apices. Treatment involved the fabrication of a complete maxillary denture. A removable device was fabricated to evaluate her response to an occlusal vertical dimension increase of 6 mm and provide a stable intercuspal position. After wearing the prosthesis for 6 months, the patient reported that she was completely free of symptoms.

Matched-pair analysis of survival in patients with poorly differentiated versus well-differentiated glottic squamous cell carcinoma

To compare survival outcomes between patients with poorly differentiated versus well-differentiated glottic squamous cell carcinoma (GSCC). Fifty-five patients with well-differentiated newly diagnosed GSCC were pair-matched to 55 patients with poorly differentiated GSCC according to age, sex, year of diagnosis, overall stage, treatment (surgery type, neck dissection, surgical margin, and chemoradiation), smoking, and alcohol use. Survival analysis was performed using Kaplan-Meier estimates, and matched-pair survival was estimated using the Cox proportional hazards regression model. Patients with well-differentiated GSCC had significantly better overall survival (OS) (P = 0.001), disease-specific survival (DSS) (P < 0.001), and disease-free survival (DFS) (P = 0.003) than patients with poorly differentiated GSCC. Moreover, matched-pair analysis indicated that increased differentiation was associated with a significantly reduced risk of overall death (HR, 0.18; 95% confidence interval [CI], 0.07–0.46), death owing to disease (HR, 0.16; 95% CI, 0.05–0.45), and disease recurrence (HR, 0.17; 95% CI, 0.07–0.41), and these risks were reduced approximately 4-fold, 3.7-fold, and 9-fold, respectively, after adjustment for cancer-associated variables. Survival differed significantly between the well-differentiated and poorly differentiated GSCC patients after adjustment for cancer prognosis-associated variables. Thus, identifying potential differences in the molecular characteristics between these two groups of patients would help to further stratify these patients and ensure appropriate individualized treatment decisions. Basing treatment strategies on the level of differentiation may improve survival.

Dental implant treatment in a young woman after marginal mandibulectomy for treatment of mandibular gingival carcinoma: a case report

Dental implants play an important role in postoperative rehabilitation after surgical treatment of oral cancer through the provision of prosthetic tooth replacement. Two major implant prosthesis designs are available: fixed implant-supported prostheses and implant-supported overdentures. We herein report a case of a 16-year-old female patient who underwent alveolar ridge resection for treatment of mandibular gingival carcinoma. Following surgery, oral rehabilitation was attempted using an implant-supported overdenture on a gold bar retainer splinting four implants. However, the patient was not satisfied with this prosthesis because of mucosal pain and discomfort, and she gradually ceased its use. Consequently, contact with the opposing teeth caused wear of the prosthetic screws. We elected to replace the implant-supported overdenture with an implant-fixed prosthesis approximately 16 years after insertion of the overdenture to prevent further wear of the prosthetic screws. The patient was highly satisfied with the improved stability of the implant-fixed prosthesis. This case report indicates that the clinician must occasionally re-evaluate and sometimes alter the direction of treatment, even after definitive therapy has been completed.

Characteristics and referral of head and neck cancer patients who report chewing and dental issues on the Patient Concerns Inventory

BACKGROUND

Patients experience considerable dental-related difficulties following head and neck cancer (HNC) treatment including problems with chewing, dry mouth, oral hygiene, appearance and self-esteem. These can go unrecognised in busy follow-up clinics. The Patient Concerns Inventory (PCI) is specifically for HNC patients, enabling them to select topics they wish to discuss and members of the multi-professional team they want to see.

AIM

The study aimed to identify the clinical characteristics of patients raising dental concerns on the PCI and to explore the outcome of onward referral. Assessments included the PCI and the University of Washington Quality of Life Questionnaire (UW-QOL) version 4, with clinic details collated from hospital and cancer databases.

METHOD

PCI data were obtained from 317 HNC patients between 2007 and 2011. Their mean age was 63 years and 60% were male. Most had oral squamous cell carcinoma and underwent surgery. The median (IQR) time from treatment to first PCI was 13 (4-42) months.

RESULTS

Three comparison groups were identified: patients with significant chewing problems, patients without significant chewing problems who wanted to discuss dental-related concerns and patients without significant chewing problems who did not want to discuss such concerns. Fifty-two percent reported either a significant chewing problem on the UW-QOL or a wish to discuss dental-related concerns. A quarter specifically asked to talk to a dental professional. Clinical characteristics significantly associated with dental issues were stage, primary treatment and free flap reconstruction. Clinic letters were copied to only 10% of general dental practitioners (GDPs).

CONCLUSION

Better communication with GDPs is essential.

The effect of radiotherapy on survival of dental implants in head and neck cancer patients

Objectives

To explore the current literature of the survival of dental implants in irradiated head and neck cancer patients considering the role of implant location, bone augmentation, dose of radiation and timing of implant placement.

Study Design

Pubmed search was conducted to identify articles published between January 2000 and December 2014 and presenting data of dental implant survival with radiotherapy in head and neck cancer patients. Studies on animal subjects and craniofacial implants were excluded.

Results

18 articles out of 27 were eligible for inclusion in this systematic review. 12 out of 18 studies reported favorable outcome of dental implants and radiotherapy with survival rates between 74.4% and 97%. Seven out of ten studies comparing the survival rates according to site of implant placement reported that implants were found to osseointegrate with greater success in the irradiated mandible than irradiated maxilla. 5 studies which compared implant survival in irradiated native bone versus irradiated grafted bone reported that irradiated grafted bone showed a significantly reduced dental implant survival rate in comparison to irradiated native bone. 6 out of 18studies in which radiation doses exceeded 70 Gy reported lower survival rates of dental implants in comparison to the studies in which radiation doses were ≤70Gy. Higher survival rates were reported in 2 studies in which implants placement was before radiotherapy in comparison to the remaining 16 studies in which implants placement was after radiotherapy.

Conclusions

Dental implants may be affected by radiotherapy especially when they are placed in maxilla, in grafted bone, or after radiation, however, they remain a functional option for rehabilitation of head and cancer patients. More Prospective cohort studies and randomized controlled trails are still needed to draw more evidence based conclusions.

Key words:Dental implants, implant survival, radiotherapy, head and neck cancer.

Structured review of papers reporting specific functions in patients with cancer of the head and neck: 2006 - 2013

Health-related quality of life (HRQoL) focuses on 4 core domains: physical and psychological function, social interaction, disease, and treatment-related symptoms, and is a key outcome in patients with cancer of the head and neck. We reviewed papers published between 2006 and 2013 that used validated questionnaires to report functional outcome in this group. A total of 572 papers were identified and 118 of them concerned function. Specific outcomes included anxiety, chewing, maxillectomy, mucositis, pain, shoulder function, and trismus. The specific functions most often identified were xerostomia, speech or voice, and swallowing or dysphagia. A considerable body of evidence has now accumulated on HRQoL and functional outomes although the precise role of HRQoL during the planning of treatment remains controversial. Over time, the emphasis of the studies included has tended to move away from the reporting of outcomes in general to more hypothesis-driven and group-specific work.

Long-term success of dental implant-supported dentures in postirradiated patients treated for neoplasms of the maxillofacial skeleton: a retrospective study

OBJECTIVES

The reconstruction of oral function in irradiated patients with craniofacial tumors is a significant challenge. The aim of this study was to detect long-term success of dental implant-supported dentures in postirradiated patients treated for neoplasms of the maxillofacial skeleton.

MATERIALS AND METHODS

From 2004 to 2011, 36 irradiated patients underwent oral function reconstruction using implant-supported prostheses. Bone augmentation was completed using vascularized bone grafts in 22 patients. Fourteen patients were treated by hyperbaric oxygen therapy (HBO). A total of 198 dental implants were used in jaw rehabilitation. After loading, implant success rates, biological and prosthetic complications, patient satisfaction, and psychological changes were recorded.

RESULTS

Bone augmentation of the jaw was successful and vascularized grafts provided an additional vascular supply in compromised irradiated tissue. Rehabilitation was successful in all of the patients after loading. Thirty-eight dental implants failed, and 35 implants were removed. The success rate of the implants was 93.6 % for 10 years after loading. It was not a significant difference in implant success rate between the HBO group and the other groups. The prosthodontic maintenance results and complication rates showed that patients required intervention 0.19 times per year. All patients were satisfied with the oral restoration results.

CONCLUSION

The restoration of oral function in radiotherapy patients with tumor resection using implant-supported prostheses is a viable treatment option.

CLINICAL RELEVANCE

Either alone or in combination with HBO, dental implant-supported prostheses can be used an effective therapeutic approach for irradiated patients with oral function reconstruction.

Among Patients Undergoing Ablative Treatment for Oral Cancer, Does the Provision of Oral Rehabilitation Improve the Quality of Life? A Review of the Current Literature

PURPOSE

The impact of oral cancer and its treatment is well documented; therefore, oral rehabilitation (OH; eg, with prosthetics, osseointegrated implants, etc) can be indicated to restore some level of form, function, and well-being. The purpose of this study was to review the current literature and evaluate the impact of OH on quality of life (QoL) after ablative surgery.

MATERIALS AND METHODS

A systematic literature search was conducted using EMBASE, MEDLINE, and PsychINFO. The study population was composed of all articles published from 2000 to 2015. To be included, studies had to use validated, specific head and neck QoL measurements (European Organization for Research and Treatment of Cancer QoL Head and Neck Module or University of Washington QoL Questionnaire). Only 8 articles met these inclusion criteria. In this review, OH was the primary predictor variable and QoL was the primary outcome variable.

RESULTS

The 8 articles reviewed used a range of designs, including 1 randomized controlled trial, 3 prospective cohort studies, 3 case series, and 1 single-measurement cross-sectional descriptive study. Sample sizes were small (n = 26 to 102), and there was limited randomization and control of intervention and comparator groups. The overall level of evidence was weak. All studies showed a link between OH and QoL, but the results varied in significance (P < .01 to P = .95).

CONCLUSION

Overall, there appears to be improvement in QoL to varying degrees after OH. However, a more systematic use of QoL measurements is needed before any definitive conclusions can be drawn.

Dental implants in irradiated versus nonirradiated patients: A meta-analysis

The purpose of the present meta-analysis was to test the null hypothesis of no difference in dental implant failure rates, postoperative infection, and marginal bone loss for patients being rehabilitated by dental implants and being previously irradiated in the head and neck region versus nonirradiated patients against the alternative hypothesis of a difference. The study suggests that irradiation negatively affects the survival of implants, as well as the difference in implant location (maxilla vs mandible), but there is no statistically significant difference in survival when implants are inserted before or after 12 months after radiotherapy. The study failed to support the effectiveness of hyperbaric oxygen therapy in irradiated patients. It was observed that there was a tendency of lower survival rates of implants inserted in the patients submitted to higher irradiation doses. The results should be interpreted with caution because of the presence of uncontrolled confounding factors in the included studies.