Skin Cancer Epidemiology and Sun Protection Behaviors Among Native Americans.

We read, with interest, Maarouf et al's study, Skin cancer epidemiology and sun protection behaviors among Native Americans (J Drugs Dermatol. 2019; 18(5):420- 423), which provided insight regarding sun protective behaviors among American Indians (AIs).1 At the University of New Mexico (UNM) School of Medicine Department of Dermatology we are particularly invested in using such data to address the healthcare disparities we observe regarding New Mexican AI access to care.

A ZPR1 mutation is associated with a novel syndrome of growth restriction, distinct craniofacial features, alopecia, and hypoplastic kidneys.

A novel autosomal recessive disorder characterized by pre- and postnatal growth restriction with microcephaly, distinctive craniofacial features, congenital alopecia, hypoplastic kidneys with renal insufficiency, global developmental delay, severe congenital sensorineural hearing loss, early mortality, hydrocephalus, and genital hypoplasia was observed in 4 children from 3 families of New Mexican Hispanic heritage. Three of the children died before 3 years of age from uremia and/or sepsis. Exome sequencing of the surviving individual identified a homozygous c.587T>C (p.Ile196Thr) mutation in ZPR1 Zinc Finger (ZPR1) that segregated appropriately in her family. In a second family, the identical variant was shown to be heterozygous in the affected individual's parents and not homozygous in any of her unaffected siblings. ZPR1 is a ubiquitously expressed, highly conserved protein postulated to transmit proliferative signals from the cell membrane to the nucleus. Structural modeling reveals that p.Ile196Thr disrupts the hydrophobic core of ZPR1. Patient fibroblast cells showed no detectable levels of ZPR1 and the cells showed a defect in cell cycle progression where a significant number of cells remained arrested in the G1 phase. We provide genetic and molecular evidence that a homozygous missense mutation in ZPR1 is associated with a rare and recognizable multisystem syndrome.

[Biocompatibility of composites--literature review].

Composites are a large family of materials composed of polymer matrices imbedded with different types of fillers. The specific properties achievable with diverse chemical combinations provide for a wide range of implications in many industrial fields. Materials designed for medical use must not only efficiently serve the purpose of their use, but also be biocompatible to the tissues they contact and the body as a whole. Dental composites and their components have been studied intensely to assess their potential local and systemic side effects, to establish biocompatibility, in order to receive the proper conformation allowing their safe clinical use. The purpose of the following paper is to summarize several aspects of research focused on determining cytotoxicity, genotoxicity, carcinogenicity, hypersensitivity, and microbial effects of composite components, in order to ascertain in fact how biocompatible dental composite materials are. Research shows that several chemical components may be released from different types of composites, and are able to cause toxic, allergic, mutagenic and other biological effects. However, because of the small amounts applied and the unique conditions in the oral cavity, the clinical relevance of these findings is questionable. Nevertheless, caution should be taken when using these materials, to avoid possible negative outcomes. Future studies should focus on targeting most toxic components and finding biocompatible alternatives and development of materials with high polymerization efficiency in order to reduce the amount of leachable components.

[A tooth or an implant--literature based decision making].

The common use of dental implants in the daily practice led to a profound change in the available treatment strategies. The option of replacing a diagnosed doubtful tooth with an implant has become widely accepted and often used. The prognosis systems in use today are based on the three major disciplines: endodontics, periodontics and prosthodontics. Combining these three may impair and bias the decision making process and increase the tendency to base it on subjective clinical experience and personal preference. Reading and reviewing the relevant literature gives no clear tool for use. Root canal treatment is considered a highly predictable treatment procedure and a treated tooth is affected mainly by the quality and type of the fabricated restoration and the risk of caries. Periodontal treatment followed by a suitable maintenance regimen will likely allow long term tooth survival. When comparing the success rates of natural teeth rehabilitation versus implant supported restorations, it appears that with implants an additional treatment is demanded along the years. This coincides with the fact that to date there is no consensus regarding the extent of perimplantitis and perimucositis that is to be expected around a restored implant. In addition, a peri implant tissue problem or a failure of a dental implant may prove to be more challenging than a failure of a tooth. It is important to remember that a dental implant is made to substitute a missing tooth and it is a treatment modality with known and clear indications for rehabilitation of an edentulous space. The aim of this paper is to review and discuss the various aspects of whether to maintain a compromised or a doubtful tooth or to prefer a treatment modality using dental implants. In conclusion it is advised here, to incorporate the discussed issues in the decision making process towards the most suitable treatment plan.

[Retention or adhesion?].

One of the reasons for immediate or late failure of restorations is the detachment of the restoration from the tooth. Retention for the restoration could be achieved from axial walls (macromechanical retention) or from adhesion of the restoration to the remaining tooth structure. Adhesion relies on bonding of resin cement to enamel or dentin on one side and to the restorative material on the other side. Bonding to enamel is predictable. Good bonding to dentin is more of a challenge especially with indirect restorations. In those cases the restoration is delivered usually a few days after the tooth was prepared during this time the exposed dentin might be contaminated or damaged. The question is whether you can rely on adhesion when cementing indirect restorations? In order to achieve the maximal bonding strength to dentin, the hybrid layer on the dentin must be built immediately after tooth preparation. This procedure is called Immediate Dentin Sealing. In vitro and clinical studies have shown better performance of restorations cemented following the IDS procedure. The article discusses the rational and the protocol of this procedure. A clinical case is presented as an example for the possibilities following this philosophy.

[Dentinal hypersensitivity].

Dentinal hypersensitivity is defined as short and transient painful response of exposed dentin, usually cervical, to different stimuli, such as thermal, mechanical osmotic or chemical. The etiology of dentinal hypersensitivity is open tubules (because of enamel loss or gingival recession), allowing painful stimulus to reach the pulp. The hydrodynamic theory explains the mechanism through which pain is aroused. When treating dentinal hypersensitivity, dentists always have to rule out other pathologies, such as carries, leakage, postoperative sensitivity, cracked tooth etc., and only then assess pain intensity and treat the tooth. Treatment always starts with prevention of both stimulus and exposure of dentin, and reducing predisposing factors. The treatment options include OTC products, such as fluoride and/or potassium enriched mouth washes and dentifrices, or in-office treatments, such as high content fluoride varnishes and gels, potassium oxalate chelating agents, Glutaraldehyde containing tissue fixating agents, bonding materials, low viscosity glass ionomers and even non-conservative treatments such as root canal therapy or mucogingival surgical interventions.

[Wear and different restorative materials--a review].

Wear of materials is a complex and unpredictable phenomenon. The variables affecting the mechanism of wear include the properties of the two contacting materials and the surrounding and interfacial media. This paper reviews the dental wear of different restorative materials and their counter effect on the tooth structure. It presents the updated classifications for tooth surface lesions termed dental wear, and discusses the wear behavior of various restorative materials. Some guidelines for restorative material selection are given. Clinical wear bears a multifactorial etiology, understanding the mechanism of action is an important step in an appropriate restoration material selection. Each material selected should meet the individual wear behavior and needs. Individual factors may enhance the wear rates: aggressive tooth brushing, parafunctions, diet, acidic/aqueous environment, surface geometry, and diminished tooth support. Supportive treatment following restoration is important to monitor wear rates.

[Techniques for immediate restoration of teeth following root canal therapy].

It is incumbent upon the dentist to restore the form and function of endodontically treated teeth. Different approaches and materials are described in the literature for restoring the missing tooth structure, either with a cast post and core or immediately with a chair-side post and core system. This article briefly reviews the available data regarding the microbiological, prosthetic, mechanical, and periodontal aspects while emphasizing the immediate approach using amalgam, composite and glass ionomer materials. The factors affecting retention of the post are presented to guide the clinician in selecting a suitable post and core system in preserving optimal root structure to prevent root fracture. Two clinical cases are presented in which tooth structure was restored using two techniques: in one, a provisional acrylic resin shell was used to house a dowel coronal-radicular amalgam core material, the other used a copper band for a composite post and core system. Both cases emphasize the ease of production and the short chair-time in the stages of crown fabrication.

Amylopectin aggregation as a function of starch phosphate content studied by size exclusion chromatography and on-line refractive index and light scattering.

Starches with a natural 65-fold span in covalently bound phosphate content were prepared from five different crops including sorghum, cassava, three potato varieties and an exotic ginger plant, Curcuma zedoaria, with extreme starch phosphate content. These starches were subjected to size exclusion chromatography with refractive index detection (SEC/RI). A simple and rapid method for starch solubilisation was used. The conditions during solubilisation (2 M NaOH) and separation (10 mM NaOH, 50 degrees C) were such as enabling > 94% recovery of the starch without detectable degradation. The aggregation properties of the starch was investigated using on line refractive index/multi angle laser light scattering (RI/MALLS) detection. Three major regions in the SEC profile were identified, consisting of large amylopectin aggregates, amylopectin particles with radius of gyration (Rg) of approx 200 nm (400 nm blocklets) and amylose. A procedure for correction of light scattering signals spread over the SEC profile as a result of aggregate tailing was developed. The significance of the relative amounts of these three molecular species on standard starch pasting parameters, as measured by a Rapid Visco Analyzer (RVA), was investigated. Starches with a high amount of amylopectin aggregates showed high peak viscosities. Moreover, very high amounts of starch bound phosphate or amylose appears to suppress the content of large aggregates resulting in low viscosity.

[Diagnostic image (4)(Bronchoalveolar lavage fluid)]. / Diagnose in beeld (4).

Two apparently healthy male volunteers, 28 and 32 years old, were examined before participation in a drug trial. Bronchial fluid was obtained. The lavage fluid from the second volunteer who had smoked 20 cigarettes a day for the past 16 years showed marked brownish discolouration, as compared to the transparent fluid of the non smoking first volunteer.

The distribution of covalently bound phosphate in the starch granule in relation to starch crystallinity.

Five selected starches with a 60-fold span in their content of monoesterified starch phosphate were investigated with respect to distribution of glucose 6-phosphate and glucose 3-phosphate residues, amylopectin chain length distributions and gelatinisation properties. The distribution of starch phosphate in the starch granules was determined by preparation of Nägeli dextrins followed by quantitative 31P-nuclear magnetic resonance spectroscopy. Total starch phosphate content was positively correlated to the unit chain lengths of the amylopectin as well as to the chain lengths of the corresponding Nägeli dextrins. The major part (68-92%) of the total starch phosphate content was partitioned to the hydrolysed (amorphous) parts. Starch-bound glucose 6-phosphate per milligram of starch was 2-fold enriched in the amorphous parts, whereas phosphate groups bound at the 3-position were more evenly distributed. The gelatinisation temperatures of the native starches as determined by differential scanning calorimetry were positively correlated (R(2)=0.75) to starch phosphate content, while crystallinity (gelatinisation enthalpy) and crystal heterogeneity (endotherm peak width) showed no correlations to starch phosphate content. The relations between starch molecular structure, architecture and functional properties are discussed.

A combination porcelain/fiber-reinforced composite bridge: a case report.

In the search for an optimal treatment to restore the aesthetically prominent maxillary anterior dentition, new materials are continually introduced. The attention of the patients has shifted from function to aesthetics, biocompatibility of the materials utilized, and conservative preparation of teeth to be restored. To fulfill patient expectations, an advanced treatment modality has recently been developed. It combines porcelain with composite resin, thereby integrating the strength and resilience of composite resin with the aesthetic advantages of porcelain. To achieve this combination, bundles of fibers are impregnated with resin in the fabrication phase of the material. The learning objective of this article is to briefly review the past methods of fabricating a 3-unit prosthesis in the maxillary anterior region and describe the recently introduced treatment alternative.

Condylar asymmetry and age in patients with an Angle's Class II division 2 malocclusion.

The relationship of age to condylar asymmetry varies for different groups of patients with temporomandibular disorders. Those with a problem of myogenous origin show a parabolic curve, while those with an arthrogenous problem show a linear relation. A group of control subjects with no signs or symptoms of temporomandibular disorders showed no correlation between age and asymmetry index. A group of 17 patients with no signs or symptoms of temporomandibular disorders but with Angle's Class II Division 2 malocclusions and deep overbite, was studied for an age-condylar asymmetry relationship. Only patients with a maximum of one missing tooth, other than third molars, were included. As a control, a group of 22 individuals with an Angle's Class I occlusion was considered. The same exclusion criteria as above was applied to this group. Age-asymmetry indicies were plotted for both groups. No correlation between age and asymmetry index was found in either group (coefficients of determination 0.054 and 0.002, respectively). This may support the conclusion that Angle's Class II Division 2 malocclusion with deep overbite is not a major factor in the aetiology of these disorders.

Sequential manifestation of different forms of early-onset periodontitis. A case report.

Pathogenic bacteria constitute the primary extrinsic agent in the etiology of early onset periodontitis. However, the risk of developing periodontal disease is not equal for all individuals, suggesting host factors are involved in determining an individual's disease susceptibility. In this report, a case of an otherwise healthy female, who exhibited prepubertal periodontitis (PPP) at age 10, juvenile periodontitis (JP) at age 13, and rapidly progressive periodontitis (RPP) at age 29 years, is presented. Microbial, immunological, and genetic features of the case are presented. PPP, JP, and RPP are considered distinct disease entities, albeit with similar pathology and pathogenesis, yet all were manifest sequentially in the same individual. This report presents the idea that certain individuals are predisposed to early-onset periodontal diseases and the early identification of risk factors is important in the management of these individuals.

Iatrogenic exfoliation of a tooth following abuse of a rubber dam: a case report.

This report presents a case in which tooth exfoliation followed rubber dam abuse. A 40-year-old patient was referred to the prosthodontic clinic with complaints of mobility and discomfort in tooth 44, which had received an amalgam restoration. While this tooth was scaled, a piece of rubber dam appeared in the buccal sulcus. Removal of the rubber piece was followed by thorough scaling and tooth splinting. Tooth deterioration continued, and concern for the adjacent teeth necessitated extraction of tooth 44. To avoid such undesirable consequences, the integrity of the dam should be verified on its removal.

[ A case of avian tuberculosis with exudative characteristics in a horse (author's transl)]. / Een geval van aviaire tuberculose met exsudatieve kenmerken bij een paard

A case of avian tuberculosis in a horse, with fatal course, is reported. The animal was imported from Poland and became ill after some weeks, in the beginning showing non-specific symptoms which became more severe until death supervened. Post-mortem examination showed a generalised form of tuberculosis. The most important lesions were seen in the lungs, liver, kidneys, spleen, intestinal tract, bones, bone marrow, and the internal lymph nodes. Beside chronic proliferative tuberculosis of the organs, many exudative foci were found with remarkably abundant acid fast bacilli. Mixed lesions were seen, too. Mycobacterium avium was isolated in microbiological examination. The pathogenesis of the infection, the predisposing factors leading to this generalised and open form of tuberculosis and the increasing importance of avian tuberculosis for animals and man are discussed.