Needs for implant therapy in cancer patients; a retrospective study

After cancer treatment in the head and neck area, mastication and speech are often affected. Some of the problems encountered can be solved by adequate dental rehabilitation. However, dental rehabilitation is often compromised, for various reasons. The change in anatomy due to surgery often results in lack of denture bearing mucosa. The effects of radiotherapy of the salivary glands and the mucosa result in dry oral tissues and diminished retention of removable dentures. Osseointegrated implants can help to solve these problems. Implant treatment has, so far, not been widely used in cancer patients. An analysis was made of 95 consecutive patients with a tumor in the head and neck area. The indication for treatment with osseointegrated implants was reviewed and the need for implants as experienced bij patients was evaluated. Results show that 45% did not need specific prosthetic rehabilitation, and approximately 25% of the patients could benefit from osseointegrated implants. Due to general and local contra-indications and patients' refusal, only 3% actually have been treated. For complete oral rehabilitation of this group of patients the use of osseointegrated implants should be considered at an early stage, before the initial tumor treatment.     

Complete denture prosthodontics for the radiation patient

The increased use of radiation therapy for the control of oral cancer necessitates that all dentists concerned with the rehabilitation of oral cancer patients be familiar with this treatment modality. Radiologic equipment, the rationale for their use, and the sequelae to oral treatment are discussed.Misconceptions have developed concerning the advisability of prescribing complete dentures following radiation therapy. However, clinical experience in the Maxillofacial Unit at the University of California. San Francisco, indicates that most radiation patients can wear complete dentures. The need to follow sound prosthodontic techniques is advocated, along with a few modifications related specifically to the radiation patient. Patient cooperation and meticulous care during and following the placement of dentures are stressed to minimize the risk of tissue necrosis and to preserve the well-being of the patient.     

Oral rehabilitation with dental implants after cancer treatment

Background: Patients who undergo surgical management of oral cancer may greatly benefit from an implant‐supported prosthesis. This study reports on the clinical experience of dental implant placement in patients following resection of oral cancer over a 15‐year period. Controversies including the use of dental implants in irradiated tissues, and hyperbaric oxygen treatment will also be discussed. Methods: Thirty‐one patients who had dental implants placed as part of their oral rehabilitation between 1992 and 2007 were investigated. Demographic data and factors including implant survival, type of prosthesis provided, radiotherapy and the hyperbaric oxygen therapy were analysed. Results: In this retrospective study, there was a retention rate of 110 implants from a total of 115 implants placed. A high rate of implant retention was found, with 5 implant failures from a total of 115 implants placed. The 5 failed implants occurred in free flap bone that had been irradiated. Conclusions: Dental implants provide an important role in the oral rehabilitation of oral cancer patients. There may be an increased risk of implant failure in free flap bone that has been irradiated.     

Managing complications of radiation therapy in head and neck cancer patients: Part III. Provision of dentures

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Pretreatment dental assessment should be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally and, as a result, they succumb to complicated oral adverse effects after radiation therapy. The management of radiation-induced caries, a sequelae of xerostomia has been reviewed in Part II of this series. In this article, the management of difficulty with dentures, another sequelae of xerostomia following radiation therapy is reviewed.     

Survival analysis and clinical evaluation of implant-retained prostheses in oral cancer resection patients over a mean follow-up period of 10 years

STATEMENT OF PROBLEM: Dental implants have been increasingly used for prosthodontic rehabilitation of patients following oral tumor resection and postsurgical radiotherapy. However, only a few long-term studies have examined the implant survival rate and other factors related to prosthodontic treatment in oral tumor resection patients. PURPOSE: The purpose of this study was to evaluate the long-term survival of dental implants and implant-retained prostheses in oral cancer resection patients. MATERIAL AND METHODS: Ninety-three patients (63 men, 30 women) with a mean age of 59 years (range of 26-89 years) received 435 implants after the resection of a head and neck tumor. Twenty-nine patients received postsurgical radiotherapy prior to implant placement. The factors related to implant survival or failure were monitored over a mean observation period of 10.3 years (range of 5 to 161 months). Prosthodontic rehabilitation was evaluated with respect to the rates of technical failures and complications. Data were analyzed using a Kaplan-Meier curve and comparisons were made with the log-rank test or the Wilcoxon test (a=.05). RESULTS: Of the 435 implants, 43 implants were lost; the cumulative survival rate was 92%, 84%, and 69% after 3.5, 8.5, and 13 years, respectively. Twenty-eight implants in 6 patients were counted as lost since the patients had died. Twenty-nine irradiated patients received 124 implants, of which 6 implants were lost prior to prosthodontic rehabilitation. In 68 patients with 78 rigid bar-retained dentures, only minor technical complications were identified. However, all 25 fixed implant-supported restorations had no technical component failures and did not require technical maintenance. CONCLUSIONS: This study demonstrates that implant-retained and -supported prostheses in oral cancer resection patients, irrespective of the cancer treatment procedure, show lower long-term survival rates than those in patients without prior cancer surgery. Rigid fixation of the implant-supported prosthesis appears to minimize the complication rates. The poor implant survival rate was due to the higher mortality rate among these patients, and not to a lack of osseointegration.     

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

The aim of this prospective study was to assess treatment outcome and impact on quality of life of prosthodontic rehabilitation with implant-retained prostheses in head-neck cancer patients. Fifty patients were evaluated by standardized questionnaires and clinical assessment. All received the implants during ablative tumour surgery in native bone in the interforaminal area. About two-thirds of the patients (n=31) needed radiotherapy post-surgery. Both in irradiated and non-irradiated bone two implants were lost 18-24 months after installation. Peri-implant tissues had a healthy appearance. No cases of osteoradionecrosis occurred. In 15 patients no functional implant-retained lower dentures could be made for various reasons. The other 35 patients all functioned well, with an improvement in quality of life. Major improvement was observed in the non-irradiated patients. In the irradiated patients, less improvement in many functional items was observed, while items related to the oral sequelae of radiotherapy did not improve. Similar to the quality-of-life assessments, denture satisfaction was improved and tended to be higher in non-irradiated than irradiated patients. Implant-retained lower dentures can substantially improve the quality of life related to oral functioning and denture satisfaction in head-neck cancer patients. This effect is greater in non-irradiated than irradiated cancer patients.     

Period between Completion of Radiation Therapy and Prosthetic Rehabilitation in Edentulous Patients: A Retrospective Study

PURPOSE: The primary purposes of this study were: (1) to describe the number and types of complications patients had before and after insertion of a removable prosthesis (i.e., denture) following radiation therapy to the head and neck and (2) to investigate whether the time between radiation therapy and denture insertion might contribute to those complications. MATERIALS AND METHODS: This research evaluated edentulous patients and those who were rendered edentulous as a result of their cancer treatment. After obtaining institutional approval following HIPAA regulations, a total of 349 charts were identified: 152 patients from Houston Veterans Administration Medical Center (HVAMC) and 197 patients from M. D. Anderson Cancer Center (MDACC). A total of 190 patients met the inclusion criteria with data available for review. RESULTS: No significant differences were found in any of the comparisons made, except when comparing complications that occurred after the dentures were inserted and the amount of time it took for prosthetic rehabilitation. The majority of patients had no complications. The patients who received their dentures in 180 days or less had the same number of complications when compared with those patients who received their dentures in 181 to 365 days and those who had to wait longer than a year for prosthetic rehabilitation. Patients with more pre-insertion complications tended to have delayed prosthetic rehabilitation. Those patients who had complications both before and after denture insertion tended to have bilateral dosing of their radiation treatment. Patients who had received radiation therapy were 1.7 times more likely to have post-prosthesis insertion complications. The majority of patients who experienced complications before and after denture insertion had greater than 5000 cGy. CONCLUSIONS: The numbers of complications reviewed in this retrospective analysis were considerably fewer than the number expected. There appears to be no difference in the number of pre- and post-insertion complications as a function of the time delay from oral surgical procedure to start of radiation treatment (10 to 21 days vs. 22 days or more).     

Radiotherapy and the survival of dental implants: a systematic review

For patients with head and neck cancer, the effects of treatment with adjuvant radiotherapy can be devastating. Frequently there is loss of function due to tooth loss, pain and discomfort from xerostomia and mucositis, and a significant psychosocial impact. Dental implants provide an effective means of rehabilitation for many, but irradiation poses a unique set of challenges that can affect the outcome of treatment. The aims of this review were to find out whether radiotherapy in these patients affects the survival of dental implants, and to discuss details of pertinent influencing factors. An electronic search of the Medline, Web of Science, and CENTRAL databases was done to identify studies on the survival of implants in irradiated patients within specified inclusion and exclusion criteria. No restriction was placed on the year of publication. The primary outcome measure was implant survival. Seven studies involving 441 participants and 1502 implants placed into irradiated bone were included. Meta-analysis indicated that survival was significantly higher in the mandible compared with the maxilla (p = 0.04), and in non-irradiated cases compared with irradiated cases (p < 0.001). Other factors that showed a strong association with survival were radiation dose and timing of surgery. Implant-based rehabilitation is a viable option for head and neck cancer patients who have undergone radiotherapy. Whilst the short to medium-term implant survival in these cases is high, multiple factors require careful consideration for a favourable outcome. Further high-quality research and randomised controlled trials are required in this field.     

Survival of dental implants in irradiated head and neck cancer patients: a retrospective analysis

Purpose: To study the long‐term survival of dental implants placed in irradiated bone in subjects who received radiation for head and neck cancer. Materials and Method: A retrospective chart review was conducted for all patients who received dental implants following radiation treatment for head and neck cancer between May 1, 1987 through July 1, 2008. Only patients irradiated with a radiation dose of 50 Gy or greater and those who received dental implants in the irradiated field after head and neck radiation were included in the study. The associations between implant survival and patient/implant characteristics were estimated by fitting univariate marginal Cox proportional hazards models. Results: A total of 48 patients who had prior head and neck radiation had 271 dental implants placed during May 1987 to July 2008. The estimated survival at 1, 5, and 10 years was 98.9%, 89.9%, and 72.3%, respectively. Implants placed in the maxilla were more likely to fail than implants placed in the mandible (p = .002).There was also a tendency for implants placed in the posterior region to fail compared with those placed in the anterior region (p = .051). Conclusion: Dental implants placed in irradiated bone have a greater risk for failure. Survival is significantly influenced by the location of the implant (maxilla or mandible, anterior or posterior).     

Histologic evidence of osseointegration in the irradiated and reconstructed mandible: a case report

Osseointegrated implants are widely used in dental rehabilitation. They are particularly valuable if the structures supporting a denture had to be removed because of oral cancer. Additionally, many of these patients undergo radiotherapy, but cancer and radiotherapy are seen as relative contraindications for implant therapy. In the literature, there are few clinical studies documenting successful oral rehabilitation using implants in such patients. The authors report a clinical case in which histologic evidence of osseointegration can be demonstrated in an irradiated and reconstructed mandible. This observation should encourage the extended application of implants in rehabilitation following oral cancer surgery.     

Maxillofacial restoration after head and neck tumor therapy

Oral and pharyngeal cancers are among the leading cancer sites. Surgery, radiation, chemotherapy, or combination therapies are common treatment modalities. Radiotherapy and chemotherapy cause significant morbidity and long-term irreversible sequelae in the oral cavity. Surgical resection can be mutilating, disfiguring, and deeply affect self-image. Orofacial defects have unique limitations and challenges for both the surgeon and the maxillofacial prosthodontist. Microvascular surgical techniques and the use of osseointegrated implants improve the rehabilitation potential of the various head and neck defects. This article reviews current treatment modalities of tumor therapy, their consequences, and the restoration of maxillofacial defects.     

Long-term outcomes of implant-based dental rehabilitation in head and neck cancer patients after reconstruction with the free vascularized fibula flap

The study aimed at evaluating, comprehensively, implant-based dental rehabilitation in head and neck cancer patients after maxillofacial reconstruction with a vascularized free fibula flap (FFF).Data were obtained by retrospectively reviewing the medical records of patients treated in Amsterdam UMC-VU Medical Center. Dental implant survival and implant success according to the Albrektsson criteria were analyzed. Additionally, prosthetic-related outcomes were studied, with a focus on functional dental rehabilitation.In total, 161 implants were placed in FFFs, with a mean follow-up of 4.9 years (range 0.2–23.4). Implant survival was 55.3% in irradiated FFFs and 96% in non-irradiated FFFs. Significant predictors for implant failure were tobacco use and irradiation of the FFF. Implant success was 40.4% in irradiated FFFs and 61.4% in non-irradiated FFFs, mainly due to implant failure and non-functional implants. Implant-based dental rehabilitation was started 45 times in 42 patients, out of 161 FFF reconstructions (27.9%). Thirty-seven patients completed the dental rehabilitation, 29 of whom achieved functional rehabilitation. Irradiation of the FFF negatively influenced attainment of functional rehabilitation. For patients with functional rehabilitation, the body mass index varied at different timepoints: FFF reconstruction, 24.6; dental implantation 23.5; and after placing dental prosthesis, 23.9.Functional implant-based dental rehabilitation, if started, can be achieved in the majority of head and neck cancer patients after FFF reconstruction. Actively smoking patients with an irradiated FFF should be clearly informed about the increased risk for implant and prosthetic treatment failure.     

Oral adverse effects of head and neck radiotherapy: literature review and suggestion of a clinical oral care guideline for irradiated patients

Radiotherapy, alone or associated with surgery or chemotherapy, produces a significant increase in cure rates for many malignancies of the head and neck region. However, high doses of radiation in large areas, including the oral mucosa, may result in several undesired reactions that manifest during or after the completion of therapy. The multidisciplinary management is the best alternative to minimize or even prevent such reactions, and the dentist has a fundamental role in this context. This paper reviews the literature related to the main oral sequelae from head and neck radiotherapy and establishes clinical oral management protocol for these irradiated patients.     

Long‐Term Results of Endosteal Implants Following Radical Oral Cancer Surgery with and without Adjuvant Radiation Therapy

Purpose: The aim of this study was to analyze the long‐term survival of implants and implant‐retained prostheses in patients after ablative surgery of oral cancer with or without adjunctive radiation therapy. Materials and Methods: Between 1997 and 2008, 66 patients who had undergone ablative tumor surgery in the oral cavity were treated with dental implants (n = 262). Thirty‐four patients received radiation therapy in daily fractions of 2 Gy administered on 18 to 30 days. Implants were inserted in the maxilla (49; 18.7%) or mandible (213; 81.3%), in non‐irradiated residual (65; 24.8%) or grafted bone (44; 16.8%) and in irradiated residual (15.6%) or grafted bone (39; 14.9%). Seventeen fixed protheses and 53 removable dentures (34 bar attachments, 9 telescopic and 10 ball retained dentures) were inserted. Results: Mean follow‐up after implant insertion was 47.99 (±34.31) months (range 12–140 months). The overall 1‐, 5‐, and 10‐year survival rates of all implants were 96.6%, 96.6%, and 86.9%, respectively. Fourteen implants were lost in nine patients (5.3% of all implants); eight implants were primary losses, and five secondary losses because of an operation of tumor recurrence. There was no significantly lower implant survival for implants inserted into irradiated bone (p = .302), bone and/or soft‐tissue grafts (p = .436), and maxilla or mandible (p = .563). All prosthetic restorations in patients without tumor recurrence could be maintained during the observation period. Conclusions: Implant survival is not significantly influenced by radiation therapy, grafts (bone and/or soft tissue), or location (maxilla or mandible). However, implants placed in irradiated bone exhibit a higher failure rate during the healing period than those placed in non‐irradiated bone. No superstructure was particularly favorable. Osseointegrated implants can be used successfully in patients with prior history of ablative surgery with and without additional radiation therapy.     

Long-term success of dental implants in patients with head and neck cancer after radiation therapy

The purpose of this study was to analyze the long-term success and factors potentially influencing the success of dental implants placed in patients with head and neck cancer who underwent radiation therapy with a minimum total dose of 50 Gy during the years 1995–2010. Thirty-five patients (169 dental implants) were included in this study. Data on demographic characteristics, tumour type, radiation therapy, implant sites, implant dimensions, and hyperbaric oxygen therapy (HBOT) were obtained from the medical records and analyzed. Implant survival was estimated using Kaplan–Meier survival curves. Seventy-nine dental implants were placed in the maxilla and 90 in the mandible. The mean follow-up after implant installation was 7.4 years (range 0.3–14.7 years). The overall 5-year survival rate for all implants was 92.9%. Sex (P < 0.001) and the mode of radiation therapy delivery (P = 0.005) had a statistically significant influence on implant survival. Age, time of implantation after irradiation, implant brand and dimensions, and HBOT had no statistically significant influence on implant survival. Osseointegrated dental implants can be used successfully in the oral rehabilitation of patients with head and neck cancer with a history of radiation therapy. Risk factors such as sex and the mode of radiation therapy delivery can affect implant survival.     

Managing complications of radiation therapy in head and neck cancer patients: Part V. Management of mucositis

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. The second last part of this series reviews and discusses the management of complication that commonly occur to the oral mucosa, i.e. mucositis.     

Managing complications of radiation therapy in head and neck cancer patients: Part I. Management of xerostomia

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they receive radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. Part I of this series reviews the management of xerostomia. The management of the effect of xerostomia to the dentition/oral cavity is discussed in Part II.     

Effect of low level laser therapy in the reduction of oral complications in patients with cancer of the head and neck submitted to radiotherapy

The aim of this study was to assess the effect of low level laser therapy on reducing the occurrence and severity of oral complications in patients with head and neck cancer undergoing radiotherapy. Sixty head and neck cancer outpatients from a cancer hospital receiving radiotherapy were selected and randomly assigned into two groups. The laser group was irradiated with an InGaAlP laser and the control received sham laser. The assessment of complications (oral mucositis, pain) was carried out one week after starting radiotherapy, and at the fifteenth and thirtieth sessions of radiotherapy. All patients from both groups showed some degree of oral mucositis. Better outcomes were observed in the laser group when compared with the control in the follow‐up sessions, indicating lower degrees of oral mucositis, pain and higher salivary flow (p < .05). These findings support the use of laser therapy as an adjuvant treatment for the control of oral complications.     

Prevention of oral and salivary gland impairment in irradiated adolescent patients with head and neck cancer: a suggested protocol.

Patients with head and neck cancer receive high doses of localized irradiation therapy, which results in destruction of salivary gland secretion ability. Pilocarpine hydrochloride was shown to have some beneficial effect on quality of life of these patients. Most studies concentrated on adult patients with head and neck cancer with no reference to adolescents. This case report demonstrates the long-term beneficial effect of pilocarpine hydrochloride in maintaining sufficient saliva, oral soft tissue integrity, and caries-free status in an adolescent cancer patient who received a total radiation dose of 6,000 cGy. A suggested protocol for management of irradiated adolescent patients with head and neck cancer is offered.     

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.