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Effective wildlife population management requires an understanding of the abundance of the target species. In the UK, the increase in numbers and range of the non-native invasive grey squirrel Sciurus carolinensis poses a substantial threat to the existence of the native red squirrel S. vulgaris, to tree health, and to the forestry industry. Reducing the number of grey squirrels, is crucial to mitigate their impacts. Camera traps are increasingly used to estimate animal abundance, and methods have been developed that do not require the identification of individual animals. Most of these methods have been focussed on medium to large mammal species with large range sizes and may be unsuitable for measuring local abundances of smaller mammals that have variable detection rates and hard to measure movement behaviour. The aim of this study was to develop a practical and cost-effective method, based on a camera trap index, that could be used by practitioners to estimate target densities of grey squirrels in woodlands to provide guidance on the numbers of traps or contraceptive feeders required for local grey squirrel control. Camera traps were deployed in ten independent woods of between 6 and 28 ha in size. An index, calculated from the number of grey squirrel photographs recorded per camera per day had a strong linear relationship (R2 = 0.90) with the densities of squirrels removed in trap and dispatch operations. From different time filters tested, a 5 minute filter was applied, where photographs of squirrels recorded on the same camera within 5 minutes of a previous photograph were not counted. There were no significant differences between the number of squirrel photographs per camera recorded by three different models of camera, increasing the method's practical application. This study demonstrated that a camera index could be used to inform the number of feeders or traps required for grey squirrel management through culling or contraception. Results could be obtained within six days without requiring expensive equipment or a high level of technical input. This method can easily be adapted to other rodent or small mammal species, making it widely applicable to other wildlife management interventions.

The most common complication during sinus graft surgery is tearing or perforation of the Schneiderian membrane. Perforations are most likely to occur if the sinus membrane is thin. Preoperative prediction of the antral membrane thickness may be of practical importance during maxillary sinus augmentation procedures. The purpose of this investigation was to analyze a possible association between gingival phenotypes and thickness of the healthy sinus mucosa.Twenty consecutive patients without preoperative anamnestic, clinical, or radiologic signs of maxillary sinus pathologies were enrolled in the study. During otorhinolaringologic surgical interventions, maxillary mucosal biopsy specimens were endoscopically obtained from the sinus floor, and gingival thickness was measured at the maxillary anterior teeth.Eleven out of 20 individuals had thick gingival tissues, and the remaining 9 presented with thin gingival phenotype. The average thickness of the Schneiderian membrane was 0.97 +/- 0.36 mm with a wide inter-individual variability. Thickness of the sinus mucosa amounted to 1.26 +/- 0.14 mm in individuals with thick gingival architecture and 0.61 +/- 0.15 mm in subjects with thin gingival tissues. The association between thickness of the antral mucosa and periodontal phenotypes was statistically significant (P.0001).Gingival thickness seems to represent a reliable parameter to predict sinus membrane thickness. Further investigations are needed to support these preliminary data.

The authors evaluated the health of the maxillary sinus in a group of 18 patients who had undergone sinus lift surgery for implantation purposes, using computed tomography and endoscopic imaging as a means of diagnosis. The study was performed after a mean interval of 31 months. All sinus lift operations were carried out using the lateral flap technique. The authors evaluated graft characteristics and intraoperative and postoperative complications and compared the results with computed tomography and endoscopic images. Endoscopy of a maxillary sinus that underwent microlaceration of the mucosa during sinus lifting showed a situation compatible with healthy conditions. In cases complicated by macrolaceration, the endoscopic picture was typical of sinusitis, even where clinical conditions of this type were not present. In the absence of intraoperative complications, the endoscopic appearance of sinus mucosa appears to improve when autologous graft material is used.