Immunolocalization of PTCH protein in odontogenic cysts and tumors

The human patched gene (PTCH) functions in both embryologic development and tumor suppression. PTCH mutations have been found in odontogenic keratocysts. However, the expression and localization of the protein product of the gene have not been determined in odontogenic tumors and cysts. We investigated 68 odontogenic lesions by immunohistochemistry, and compared their PTCH expression with that in basal cell carcinomas. All odontogenic lesions, including two keratocysts with truncating mutations, were positive for PTCH. Different types of lesions had different amounts of staining. Lack of staining was noted in the majority of basal cell carcinomas. Taken together, these data suggest that odontogenic keratocysts arise with heterozygous mutations of the PTCH gene.     

Playing wind instruments as a potential aetiologic cofactor in external cervical resorption: two case reports

AIM: To present two cases of external cervical resorption (ECR) on maxillary incisors, in which the primary aetiologic factor is suggested to be pressure trauma by frequently playing wind instruments. SUMMARY: The exact aetiological spectrum of ECR is still poorly understood. For resorption to occur, a defect in the cementum layer (trigger) is a likely prerequisite. Whilst the mechanism for continuation (stimulus) is still unclear, knowledge of potential predisposing factors is important in assessing patients at risk. Pressure generated by playing wind instruments could present an aetiological factor in ECR because it affects the cervical region of the root surface. The cases that are presented may confirm this hypothesis and the extent of resorption defects is shown by cone-beam computer tomography (CT) and micro-focus CT imaging techniques.     

Direction of the mental canal in human mandibles

The direction of the mental canal was calculated in the horizontal and vertical planes with a view to aiding anaesthetic techniques. Based on our data, it is advisable to give the following approximate inclinations to the needle when penetrating the mental canal in anaesthetic procedures: 55 degrees postero-anteriorly in relation to a horizontal plane and 40 degrees latero-medially in relation to a horizontal line tangent to the body of the mandible at the level of the mental foramen.     

Reimpianto dentale in soggetto affetto da paralisi cerebrale infantile: problemi di valutazione medico-legale del danno

Objectives

Analysis of the parameters used for the medicolegal assessment of damages in a case of tooth avulsion and replantation in a child with cerebral palsy.

Materials and methods

The authors report a case of traumatic tooth avulsion in a child with cerebral palsy. During recess at school, the girl fell out of her wheelchair, which was being pushed by her schoolmates, and suffered maxillofacial trauma associated with superior incisor avulsion. The tooth was replanted within 60 minutes, but it fell out 6 years later. Because the traumatic event leading to the avulsion had occurred at school, the parents filed a claim for damages with the school's insurance company.

Discussion

The authors review the procedure for arriving at a fair assessment of the damage, based on the child's condition before the trauma and data in the literature on life expectancy in subjects with cerebral palsy and factors affecting the duration of the tooth replants.     

The number of implants required to support a maxillary overdenture: a systematic review and meta-analysis

Purpose

The number of implants needed to support a maxillary overdenture is still a controversial issue. The aim of this systematic review was to investigate the number of implants required to support a maxillary overdenture in order to obtain optimal treatment outcomes in terms of implant survival, overdenture longevity and patient satisfaction.

Capnocytophaga in the dental plaque of immunocompromised children with cancer

OBJECTIVES: (i) To compare the prevalence and levels of Capnocytophaga, a known systemic pathogen in immunocompromised patients, in the dental plaque of healthy children and children with cancer, and (ii) to determine the susceptibility of strains isolated from cancer patients to a range of antibiotics. PATIENTS AND METHODS: Thirty-one children with cancer undergoing a first course of immunosuppressive chemotherapy and 30 healthy control children were included in the study. Samples were collected on days 0, 7, 14, and 21 of the cure (and equivalent dates in controls). Susceptibility to antibiotics was tested using an agar dilution method and galleries with predefined concentrations of selected antibiotics. RESULTS: There was a significant drop in the total anaerobic cultivable flora on day 14 and in the prevalence of Capnocytophaga on days 14 and 21 in the children with cancer. The proportion of Capnocytophaga in the anaerobic flora, however, was high in certain cancer patients. Beta-lactam/beta-lactamase inhibitor combinations, imipenem, clindamycin, and tetracycline were the most effective against Capnocytophaga. CONCLUSION: This study showed that Capnocytophaga decreased in prevalence and proportion in the dental plaque of cancer patients during chemotherapy but became predominant in some cases. It is recommended that imipenem or beta-lactam/beta-lactamase inhibitor combinations be used to treat Capnocytophaga bacteraemia.     

Radiation-induced mandibular adult spindle cell rhabdomyosarcoma

Spindle cell rhabdomyosarcoma (RMS), a variant of embryonal RMS, is a rare tumour, especially in adults. Imaging techniques are used to evaluate the extent of the tumour whereas a biopsy is required to make the final diagnosis. In this article we describe a case of mandibular Spindle cell RMS in a previously irradiated field in a 56-year-old male, and discuss the clinicopathologic and imaging findings. Although the aetiology is still unclear, this case suggests that previous radiation therapy can be a causal factor.