Factors Affecting Survival and Usefulness of Implants Placed in Vascularized Free Composite Grafts Used in Post–Head and Neck Cancer Reconstruction

Background: Bone‐containing vascularized grafts have been used successfully to reconstruct post‐cancer surgical defects. Dental implants can be placed in these bone‐containing grafts to allow implant‐supported prosthodontic reconstruction of these patients. Purpose: The aim of this study was to evaluate the survival of dental implants used in the rehabilitation of subjects treated with bone‐containing vascularized grafts to compare usability of implants placed at the time of reconstruction and after healing. Materials and Methods: A cross‐sectional study was undertaken to examine survival rates of implants placed in vascularized bone‐containing grafts either immediately at the time of surgical reconstruction or after 3 months healing. Other factors such as graft type, whether radiation therapy was given, and implant type were recorded. Results: A total of 41 patients had 145 implants placed in 47 vascularized bone‐containing flaps. Increased failure rate of implants was seen in immediately placed implants. There was also a significant increase in the number of osseointegrated implants that were prosthodontically unusable or sub‐optimally placed in the immediate placement group. Radiation therapy was associated with a significant increase in failure rate. Modern implant surfaces appeared to perform better than machined/turned surfaces. Graft donor site did not influence implant survival. Conclusion: This study demonstrated the difficulties encountered with immediate placement of dental implants at the time of post‐cancer reconstructive surgery.     

A clinicopathological study of serotonin of sigmoid colon mucosa in association with chronic symptoms in uncomplicated diverticulosis

Introduction

Neurotransmitter imbalance is hypothesised as a pathogenetic mechanism in several bowel conditions. We previously reported increased 5-HT in the sigmoid mucosa of colon resected for complicated diverticular disease (DD). We aimed to identify if abnormal 5-HT expression is associated with symptoms of uncomplicated DD.

Methods

This was a prospective, comparative study and follow-up survey of symptoms. We examined the differences in 5-HT between DD patients and controls, as well as the presence of bowel symptoms at time of endoscopy and also 2?years later. Sigmoid biopsies were collected at colonoscopy. Immunohistochemical staining for 5-HT cells was performed.

Results

Eighty-seven patients were recruited, 37 (42.5?%) DD and 50 (57.5?%) controls. No patients underwent surgery. There was no significant difference in total mean number of 5-HT-positive cells in DD compared to controls or between patients and controls with abdominal symptoms. Forty-one patients (47.1?%) responded to questionnaires at median 57.8?months from biopsy. Eighteen (43.9?%) were DD and 23(56.1?%) controls. 5-HT counts showed no significant association to symptom persistence.

Discussion

Although 5-HT expression has previously been found to be increased in complicated DD in whole bowel-resected specimens, the same is not confirmed on colonic mucosal biopsies. This raises the suggestion that 5-HT may be involved in the development of acute complications but may not be involved in the pathogenesis of chronic symptoms.     

Unvaccinated children in years of increasing coverage: how many and who are they? Evidence from 96 low‐ and middle‐income countries

Objective While childhood immunisation coverage levels have increased since the 70s, inequities in coverage between and within countries have been widely reported. Unvaccinated children remain undetected by routine monitoring systems and strikingly unreported. The objective of this study was to provide evidence on the magnitude of the problem and to describe predictors associated with non‐vaccination. Methods Two hundred and forty‐one nationally representative household surveys in 96 countries were analysed. Proportions and changes in time of ‘unvaccinated’ (children having not received a single dose of vaccine), ‘partially vaccinated’ and ‘fully vaccinated’ children were estimated. Predictors of non‐vaccination were explored. Results The percentage of unvaccinated children was 9.9% across all surveys. 66 countries had more than one survey: 38 showed statistically significant reductions in the proportion of unvaccinated children between the first and last survey, 10 countries showed increases and the rest showed no significant changes. However, while 18 of the 38 countries also improved in terms of partially and fully vaccinated, in the other 20 the proportion of fully vaccinated decreased. The predictors more strongly associated with being unvaccinated were education of the caregiver, education of caregiver’s partner, caregiver’s tetanus toxoid (TT) status, wealth index and type of family member participation in decision‐making when the child is ill. Multivariable logistic regression identified the TT status of the caregiver as the strongest predictors of unvaccinated children. Country‐specific summaries were produced and sent to countries. Conclusion The number of unvaccinated children is not negligible and their proportion and the predictors of non‐vaccination have to be drawn from specific surveys. Specific vaccine indicators cannot properly describe the performance of immunisation programmes in certain situations. National immunisation programmes and national and international immunisation stakeholders should also consider monitoring the proportion of unvaccinated children (i.e. those who have received no vaccines at all) and draw specific plans on the determinants of non‐vaccination.