Prosthodontic complications during implant-based oral rehabilitation of patients with head and neck cancer.

STATEMENT OF PROBLEM: Implant-retained prosthodontic rehabilitation of patients with head and neck cancer is complex. However, the extent of prosthodontic complications has been sparsely reported within the literature. PURPOSE: The purpose of this retrospective study was to describe the range of complications and issues that affected the oral rehabilitation treatment of patients with head and neck cancer who had completed implant-retained prosthodontic rehabilitation in a tertiary treatment center. MATERIAL AND METHODS: A retrospective analysis of complications and their consequences in patients treated in a regional unit from 2012 to 2017 was performed. Descriptive analysis was carried out on the type and frequency of complications and their consequences for the patients' treatment. Complications were grouped into the following complication types: local and systemic, implant, peri-implant soft tissue, and clinical prosthodontic complications. Implant success and implant survival were also reported. RESULTS: The sample was composed of 163 patients with head and neck cancer who had completed implant-retained prosthodontic rehabilitation. Local and systemic complications affected 8.6% of patients, and peri-implant soft-tissue complications affected 9.8% of patients. Clinical prosthodontic complications leading to repeated clinical or laboratory stages occurred on 48 occasions in 45 patients (27.6% of patients). A total of 763 implants were placed. Implant survival was 95.8% and implant success 94.5%, with a mean follow-up of 42.1 months. CONCLUSIONS: This retrospective evaluation indicated that complications arising during the process of implant-retained prosthetic rehabilitation in this patient group were variable and common. Such complications can delay the process of treatment and lead to repeating or restarting clinical and laboratory stages of treatment.

Survival rate and complication-free survival rate of implant-retained prostheses in the oral rehabilitation of patients with head and neck cancer: A retrospective evaluation of a cohort from a regional service.

STATEMENT OF PROBLEM: Literature reporting on the prosthetic survival and complications of implant-retained prostheses in patients with head and neck cancer is sparse. PURPOSE: The purpose of this retrospective study was to present the survival rates and complication-free survival rates of both fixed and removable implant-retained oral prostheses in patients with head and neck cancer while also reporting on the frequency and causes of failure and complications for each prosthesis type. MATERIAL AND METHODS: A retrospective analysis of the prosthetic survival rates and complication-free survival rates of implant-retained oral prostheses and the frequency and causes of failure and complications in patients with head and neck cancer treated in a regional unit from 2012 to 2017 was performed. Differences in categorical and continuous data were assessed for statistical significance by using the Pearson chi-square test, Fisher exact test, t test, and analysis of variance as appropriate. Cox proportional hazard regression models were fitted to evaluate the association between prostheses type, clinical and medical factors, and the outcomes of survival and complication-free survival. Descriptive statistics were used to analyze the frequency and type of prosthetic complications. RESULTS: The sample was composed of 153 patients diagnosed with head and neck cancer who had completed implant-retained prosthodontic rehabilitation and had been provided with 221 prostheses. The 5-year survival rate was 87% for maxillary fixed prostheses, 79% for mandibular fixed, 66% for maxillary removable, and 50% for mandibular removable. Hazard ratios were calculated showing that the 5-year survival rate of a mandibular removable prosthesis (HR=5.1; 95% CI 1.60-16.25) (P=.006) was greater than that of a maxillary fixed prosthesis (HR=1.0). The 5-year complication-free survival rate was highest for mandibular fixed prostheses (62%), followed by maxillary fixed (58%), maxillary removable (36%), and mandibular removable prostheses (29%). Hazard ratios showed that the 5-year survival rate of maxillary removable (HR=1.91; 95% CI 1.01-3.66) (P=.048) and mandibular removable prosthesis (HR=2.29; 95% CI 1.23-4.25) (P=.009) was greater than that of a maxillary fixed prosthesis (HR=1.0). Variables of radiotherapy, grafting, age, and sex and their influence on the survival rate and complication-free survival rate were assessed but were not statistically significant. CONCLUSIONS: This evaluation indicated that fixed implant-retained prostheses had a higher 5-year survival rate and 5-year complication-free survival rate than removable implant-retained prostheses in patients with head and neck cancer.

Outcomes of implant-based oral rehabilitation in head and neck oncology patients-a retrospective evaluation of a large, single regional service cohort.

BACKGROUND: The study reports on implant survival outcomes in head and neck cancer patients who received implant-based oral rehabilitation in a regional service centre. METHODS: A retrospective analysis of implant survival outcomes in patients treated in a regional service from 2012 to 2017 was performed. The primary outcome measure was implant survival. The secondary outcome measure was to assess the effect of covariates associated with implant failure including bone type, radiotherapy, chemotherapy, gender and surgical implant complications. Kaplan-Meier survival curves were applied to compare differences in the survival rates of groups of variables. Cox proportional hazards models were applied to identify covariates associated with implant failure. p value was set at 0.05. RESULTS: The sample was composed of 167 head and neck cancer patients who had 779 dental implants placed. Implant survival estimates were calculated: 3 years, 95.7% [95%CI 94.3-97.2%] and 5 years, 95.5% [95%CI 93.9-97.0%], with a median follow-up of 38 months. Gender (p = 0.09), radiotherapy (p = 0.16) and chemotherapy (p = 0.17) did not significantly influence implant survival, whereas implant failure was higher in transported (reconstructed) bone sites in comparison with native bone (p < 0.01). CONCLUSION: The result of this study suggests that overall implant survival as part of the routine oral rehabilitation is high in this patient cohort; however, implant failure was found to be statistically higher for implant placed into transported bone in comparison to native bone.

An investigation into the effects of metal primer and surface topography on the tensile bond strength between cobalt chromium alloy and composite resin.

This study examined the influence of surface preparation and metal primer on the tensile bond strength between cobalt chromium alloy and composite resin. The bond strength between 168 cobalt chromium alloy dumb-bells with one of three test surfaces (beaded, machined or sandblasted) to composite resin were tested. Half of each group were treated with metal primer. The weakest bond strength was produced by the unprimed machined surface, many specimens failing before testing. The metal primer increased the bond strengths of all groups tested. The greatest bond strengths were achieved with the primed beaded and sandblasted surfaces. Within the limits of the study it has been shown that the surface preparation of the cobalt-chromium alloy did influence tensile bond strengths with composite resin and Metal Primer II increased the tensile bond strengths for all groups tested. The sandblasted surface treated with Metal Primer II is recommended for the bonding of composite resin to cobalt chromium alloy.

Medicinal erosion: a case report.

Patients, healthcare professionals, and health product manufacturers focus on the benefits that the use of a medicine or health product will bring rather than the potential side effects. A case of erosive tooth surface loss caused by the repeated and prolonged use of an acidic mouthrinse is reported. The adverse effects of health care products on the dentition and methods to minimise potential damage are discussed.