Objectives: Conventionally and digitally manufactured removable complete dentures with different dentition forms were examined for manufacturing accuracy (trueness, precision), fracture forces under torsional loading and subsequent repairability.
Methods: A total of 90 mandibular prostheses were manufactured. Ten were made using the injection molding technique and finished with prefabricated teeth.
A protocol for a completely digital manufacturing process for an obturator prosthesis is described. An intraoral scanner was used to capture the mandible and maxilla together with the sinus defect. The obturator base and the artificial teeth were created with a computer-aided design software program and manufactured by 3-dimensional printing.
View Article and Find Full Text PDFTitanium dental implants with sandblasted and/or acid-etched surfaces have shown clinical superiority in comparison to their smooth, machined counterparts, and are now state of the art. Sandblasting of finished, sintered zirconia implants, however, will damage the surface structure and affect the mechanical properties. To improve osseointegration of zirconia dental implants without impairing the original mechanical strength by crack initiation and partial phase transformation from tetragonal to monoclinic, roughening of the zirconia surface by sandblasting before the final sintering step was employed.
View Article and Find Full Text PDFBecause optimal reconstruction of maxillofacial defects requires functional rehabilitation, the current study demonstrates the successful secondary reconstruction of a large mandibular continuity defect using a fully digitally planned prefabricated free vascularized fibula with immediate implant-supported prosthodontic restoration. A 56-year-old man presented with a large mandibular continuity defect after resection of an enlarged squamous cell carcinoma arising from the floor of the mouth. For secondary reconstruction, the shape of the neomandible and implant position for support of the lower prosthesis were planned virtually.
View Article and Find Full Text PDFBerl Munch Tierarztl Wochenschr
March 2015
To identify typical trauma patterns or frequent radiological pitfalls that could help a radiologists in their daily routine, a retrospective study of Salter-Harris fractures in dogs and cats was performed. Radiographs obtained in the period 1991-2012 of 288 fractures in 245 patients with suspected injuries affecting growth plates in the appendicular skeleton were retrieved from the imaging archive. The femur was the bone most frequently affected (46.
View Article and Find Full Text PDFHydrophilicity of unset impression materials underlies changes occurring during working time. Hence, the clinical application time when impression materials contact oral tissues after mixing may play a critical role in successful impressions. The aim of this study was to analyze the clinical time course of impression taking applying the single-step/double-mix technique.
View Article and Find Full Text PDFIntrusion injuries are considered among the most severe forms of dental trauma, potentially leading to ankylosis as a late consequence. In 1991, a 7-year-old boy suffered a traumatic intrusion leading to an infraposition of tooth 21 along with its immobility. Based on the clinical findings, including bright-sounding percussion testing, disappearance of the periodontal space and a failed attempt at orthodontic movement, a diagnosis of ankylosis was made.
View Article and Find Full Text PDFIn the past years, tattoos have become very popular worldwide, and millions of people have tattoos with mainly black colours. Black tattoo inks are usually based on soot, are not regulated and may contain hazardous polycyclic aromatic hydrocarbons (PAHs). Part of PAHs possibly stay lifelong in skin, absorb UV radiation and generate singlet oxygen, which may affect skin integrity.
View Article and Find Full Text PDFMillions of people are tattooed with inks that contain azo pigments. The pigments contained in tattoo inks are manufactured for other uses with no established history of safe use in humans and are injected into the skin at high densities (2.5 mg/cm(2)).
View Article and Find Full Text PDFPurpose: To investigate the light-induced decomposition of indocyanine green (ICG) and to test the cytotoxicity of light-induced ICG decomposition products.
Methods: ICG in solution was irradiated with laser light, solar light, or surgical endolight. The light-induced decomposition of ICG was analyzed by high-performance liquid chromatography (HPLC) and mass spectrometry.
Contact Dermatitis
April 2008
Background: Modern tattoo colourants frequently consist of azo pigments that not only contain multiple impurities but also are originally produced for car paint and the dyeing of consumer goods.
Objective: In order to be able to assess the health risk of tattoos, it is important to determine the pigment concentration in human skin.
Methods: We tattooed excised pigskin and human skin with a common tattoo pigment (Pigment Red 22) under various conditions.
Basal cell carcinoma is the most common malignant neoplasm of the skin, whereas the localization at the nail unit is very rare. We report the case of a 58-year-old patient with a periungual basal cell carcinoma at the thumb. The specific feature of the reported case is the frequent exposure to fishing baits that the patient had stained with an unknown colorant.
View Article and Find Full Text PDFBackground: Millions of people have at least one tattoo. Complex and light absorbing molecules are implanted in the skin. When tattooed skin receives UV radiation or natural sunlight, photochemical cleavage of the pigments may occur.
View Article and Find Full Text PDFTattooing is a widespread process of puncturing pigments into skin, whereas the resulting concentration inside the skin remains unknown. Many tattoo colorants are organic pigments, such as azo pigments, manufactured for other uses. To remove tattoos from skin, laser pulses at very high intensities are applied to the skin to destroy the tattoo pigments.
View Article and Find Full Text PDFUVA light (320-400 nm) has been shown to produce deleterious biological effects in tissue due to the generation of singlet oxygen by substances like flavins or urocanic acid. Riboflavin, flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), beta-nicotinamide adenine dinucleotide (NAD), and beta-nicotinamide adenine dinucleotide phosphate (NADP), urocanic acid, or cholesterol in solution were excited at 355 nm. Singlet oxygen was directly detected by time-resolved measurement of its luminescence at 1270 nm.
View Article and Find Full Text PDFIn the dog, unlike most other domestic animal species, corpus luteum (CL) life span is not affected by hysterectomy. Only in pregnant dogs, during the immediate prepartum decline of progesterone, does PGF2alpha clearly seem to act as an endogenous luteolytic agent. Whether endogenous PGF2alpha plays a role in the slow regression of the corpora lutea of the nonpregnant cycle is not known.
View Article and Find Full Text PDFControl of luteal regression in the dog is still poorly understood. Unlike other domestic animal species, luteolysis is not prevented by hysterectomy. Indications that PGF(2alpha) may act as an endogenous luteolytic agent have been found only in pregnant animals during the prepartal decline of progesterone.
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