Frequency, location, and direction of the lateral, secondary, and accessory canals

Observation of 1,140 transparent teeth of adult humans was made to verify the frequency, location, and direction of the accessory, secondary, and lateral canals located at the radicular-apical area, at the body of the root, and in the base of the root. In 27.4% of the teeth studied, some type of ramification was observed; these ramifications were usually located in the apical area of the root. The premolars and molars showed the greatest variety of ramifications.     

Variability of the nasion-subnasal, subnasalgnathion, and bizygomatic distances of individuals of 6, 7, 11, and 15 years of age and their importance in the determination of the vertical dimension

A study of the cephalometric points which represent the height and width of the face was undertaken in the city of Piracicaba on 576 boys and girls aged 6, 7, 11, and 15 years. Analysis of the data shows that the measurements increased progressively and proportionately with age and the importance of the cephalometric points in the determination of the vertical dimension in occlusion.     

Attrition, eruption, and the periodontium

Features of natural masticatory function, of physiological attrition, both occlusal and approximal, and of continuing tooth eruption in adult life need to be borne in mind in considering how the chronic inflammatory periodontal diseases and dental caries have become so widespread. Evidence is reviewed showing that teeth continue to erupt in adulthood, that natural masticatory function prevented plaque accumulation at the approximal risk site of onset of both CIPDs and caries, that epithelial attachment to cementum may be physiological, and that periodontal attachment studies must be age-related.     

Instrumentation and techniques for examination of the ear, nose, throat, and sinus

Optimal and accurate management of any patient depends on a detailed history and thorough physical examination. The information garnered dictates the definitive management of the patient. Adequate examination of the head and neck, particularly the upper aerodigestive tract, presents a unique challenge because much of the area to be examined is not easily accessible to direct visualization. However, advances in medical technology have prompted the evolution of the instrumentation and the techniques used to examine this anatomic region. This evolution allows for a more informative assessment of the patient and a more comfortable experience.     

Correlation Between Tooth width,width of the Head,Length of the Head,and Stature

The present summary and the following papers (I-VIII) are submitted in partial fulfillment of the requirements for the degree of Doctor Philosophiae at the University of Oslo.

I. Composition of dental resin and composite materials. Acta Odontol. Scand. 1981, 39, 133–146

Co-author: I.J. Sjøvik

II. Remaining methacrylate groups in composite restorative materials. Acta Odontol. Scand. 1978, 36, 75–87

Co-author: S.A. Svendsen

III. Conversion in different depths of ultraviolet and visible light activated composite materials. Acta Odontol. Scand. 1982. 40, 179–192 Co-author: H. øysæd

IV. Compressive creep of light cured resin based restorative materials. Acta Odontol. Scand. 1982. 40, 319–324

Co-author: H. øysæd

V. Flexural properties of denture base polymers. J. Prosthet. Dent. 1980, 43. 95–104

Co-author: S.A. Svendsen

VI. Compressive creep of denture base polymers. Acta Odontol. Scand. 1980, 38, 169–177

Co-author: S. Espevik

VII. Conversion in denture base polymers. J. Biomed Mater. Res. In press Co-author: H. øysæd

VIII. Release of formaldehyde from denture base polymers. Acta Odontol. Scand. 1980, 38, 17–27

In this summary these papers will be referred to as Papers I-VIII. Other literature cited will be referred to in the conventional manner.     

Derangement, osteoarthritis, and rheumatoid arthritis of the temporomandibular joint: implications, diagnosis, and management

Temporomandibular joint (TMJ) dysfunction is often believed to bea young person's malady. However, geriatric patients also present with clinical findings of TMJ clicking, locking, crepitation, limited opening, and pain. With our aging population and the high prevalence of rheumatic and musculoskeletal diseases in the elderly, it is important to understand the etiopathogenesis, clinical presentation, and management of derangement, rheumatoid arthritis, and osteoarthritis of the TMJ. Although arthritis of the TMJ usually causes only mild-to-moderate dysfunction in older patients, they present challenges related to medication use and comorbidity. This article presents the most recent understanding and therapeutic protocols for patient diagnosis and management.     

Effects of the natural compound,oxyresveratrol, on the growth of Streptococcus mutans,and on biofilm formation,acid production,and virulence gene expression

Streptococcus mutans is one of the major pathogens of dental caries. Oxyresveratrol, a natural compound found in plants, exerts inhibitory effects on many bacterial species but its effect on S. mutans is unknown. The objective of this study was to clarify the antibacterial effect of oxyresveratrol on S. mutans, including effects on basic viability, acidogenicity, acidurity, and extracellular polysaccharide synthesis. The expression of nine genes that encode virulence and protective factors in S. mutans was measured by qRT-PCR. Oxyresveratrol showed a dose-dependent inhibitory effect on survival of S. mutans. At 250 μg ml⁻¹, oxyresveratrol reduced the S. mutans survival rate, inhibited synthesis of water-insoluble glucans, compromised biofilm formation, and significantly down-regulated the expression of glucosyltransferase-I (gtfB) and glucosyltransferase-SI (gtfC). However, the enzymatic activity of lactate dehydrogenase protein was increased and the expression of lactate dehydrogenase (ldh) and ATP synthase subunit beta (atpD) genes were also up-regulated. Besides, glucosyltransferase S (gtfD) up-regulation indicated that water-soluble glucan synthesis was promoted. The vicR, liaR, and comDE genes, which exert a self-protective function in response to external stress, were also up-regulated. In conclusion, oxyresveratrol inhibited the growth of S. mutans and also reduced biofilm formation, acid production, and synthesis of water-insoluble glucans by this organism. In addition, oxyresveratrol also activated a series of S. mutans self-protection mechanisms.     

Tobacco cessation, the dental profession, and the role of dental education

This article describes the development of a comprehensive, interdisciplinary, tobacco cessation program based on twenty years of experience at the Indiana University (IU) School of Dentistry. It reviews the relationship between tobacco use and oral health, the nature of nicotine addiction and cessation approaches involving nicotine replacement therapy. In the early 1980s, tobacco control curriculum and cessation guidelines were introduced at the IU School of Dentistry and cooperative efforts initiated with other U.S. and Canadian dental schools. During the past decade, an interdisciplinary Nicotine Dependence Program has been developed to serve outpatients receiving treatment at all hospitals on the IU Medical Center campus. It is hoped that the models described here will be of value to other dental schools developing educational curricula and tobacco control and cessation programs.     

Immunohistochemical studies of the neurochemical markers, CGRP, enkephalin, galanin, gamma-MSH, NPY, PHI, proctolin, PTH, somatostatin, SP, VIP, tyrosine hydroxylase and neurofilament in nerves and cells of the human attached gingiva

Punch biopsies were obtained from the buccal gingiva of the lower third molars. Thin nerve fibres, immunoreactive for calcitonin gene-related peptide (CGRP) or substance P (SP), with possible sensory function, were found in the propria often close to the epithelium, sometimes even penetrating into the basal layers. gamma-Melanocyte stimulating hormone (gamma-MSH)-like immunoreactivity was found in sparsely distributed single cells (except in one specimen containing a dense infiltration), resembling neutrophilic granulocytes of the propria. gamma-MSH was present in several single smooth axons and in thick axon bundles of the propria. Surrounding the blood vessels, neuropeptide Y (NPY), tyrosine hydroxylase (TH), vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine amide (PHI) immunoreactive nerve fibres were observed. NPY and TH-positive fibres probably represent sympathetic nerve terminals and VIP/PHI-immunoreactive ones may have a parasympathetic function. Papillae of the propria contained VIP-positive fibres not obviously related to blood vessels. The distribution in papillae of PHI-like immunoreactivity was similar but the PHI-positive reaction was also present in a few cells of the propria, especially near blood vessels. Somatostatin (SOM)-positive reaction occurred in a few dendritic-type cells near or in the epithelium and single nerve fibres close to the epithelium. Several thick axon bundles of the propria contained neurofilament (NF)-immunoreactive material. Some thin NF-fibres were found in the papillae and some seemed to penetrate into the epithelium. No galanin, methionine-enkephalin, parathyroid hormone or proctolin immunoreactive material was found. The rather rich content of several neuropeptides in human attached gingiva, as well as other neurochemical markers, is probably associated with sensory and autonomic functions.     

Bioengineered tissues: the science, the technology, and the industry

Authors – Ahsan T, Nerem RM Objective – The bioengineering of tissues and organs, sometimes called tissue engineering and at other times regenerative medicine, is emerging as a science, as a technology, and as an industry. The goal is the repair, replacement, and/or the regeneration of tissues and organs. The objective of this paper is to identify and discuss the major issues that have become apparent. Results – One of the critical issues is that of cell source, i.e. what will be the source of the cells to be employed? Another critical issue is the development of approaches for the fabrication of substitute tissues/organs and/or vehicles for the delivery of biological active molecules for use in the repair/regeneration of tissues. A third critical issue, one very much related to cell source, is that of immune acceptance. In addition, there are technological hurdles; there are additional issues such as the scale‐up of manufacturing processes and the preservation of living‐cell products for off‐the‐shelf availability. Although the initial products have been superficially applied skin substitutes, as this fledgling industry continues to evolve, it is beginning to focus on a wider range of more invasive and complicated products. From a public health perspective, the real opportunity may be in addressing chronic diseases, as well as the transplantation crisis (i.e. the tremendous disparity between patient need for vital organs and donor availability) and, equally important is the challenge of neural repair. Conclusion – These are the grand challenges, and the scientific community, business/private sector, and federal government must mobilize itself together in this emerging area to translate the benchtop science to the patient bedside.     

Interrelationships between the width, depth, and perimeter of the dental arch

Recently, beta function has been shown to be an accurate mathematical model of the human dental arch. In this article a beta function-based nomograph is presented that shows interrelationships between arch width, arch depth, and arch perimeter. This nomograph can be especially useful in predicting the effect of orthognathic surgery on these 3 variables of a dental arch.     

Viral,bacterial, and fungal infections of the oral mucosa: Types,incidence, predisposing factors,diagnostic algorithms,and management

For millions of years, microbiota residing within us, including those in the oral cavity, coexisted in a harmonious symbiotic fashion that provided a quintessential foundation for human health. It is now clear that disruption of such a healthy relationship leading to microbial dysbiosis causes a wide array of infections, ranging from localized, mild, superficial infections to deep, disseminated life‐threatening diseases. With recent advances in research, diagnostics, and improved surveillance we are witnessing an array of emerging and re‐emerging oral infections and orofacial manifestations of systemic infections. Orofacial infections may cause significant discomfort to the patients and unnecessary economic burden. Thus, the early recognition of such infections is paramount for holistic patient management, and oral clinicians have a critical role in recognizing, diagnosing, managing, and preventing either new or old orofacial infections. This paper aims to provide an update on current understanding of well‐established and emerging viral, bacterial, and fungal infections manifesting in the human oral cavity.     

Activities of hexokinase, phosphofructokinase and pyruvate kinase in the gingival tissue of the rat, hamster, guinea pig and human

The activities of three important enzymes of the glycolytic pathway, namely, hexokinase, phosphofructokinase and pyruvate kinase in the gingival tissue of the rat, hamster, guinea pig and human were determined. The results obtained in the present investigation reveals that the specific activities for hexokinase and pyruvate kinase were highest for the mucosal gingiva of the rat, while guinea pig presented the greatest value for phosphofructokinase. The specific activities of these enzymes were about the same for both attached gingiva of guinea pig and human.     

母体营养状况与唇腭裂发生关系的研究

目的通过检测母体血清,了解其营养状况,分析唇腭裂发生与母体营养状况的关系,为降低唇腭裂的发生开辟新途径。方法收集唇腭裂患者母亲血液（Ⅰ组）和正常婴儿母亲（Ⅱ组）血液样本各78例,采用原子吸收光谱分光光度法测量血清中营养物质（锌、钙、镁、铜、铁、总蛋白、甘油三酯、胆固醇及血糖）的含量,比较分析两组营养物质含量有无差异。结果Ⅰ组血清锌的含量明显低于Ⅱ组,两组间比较P〈0.001,有统计学意义;而Ⅰ组血清铜、铁、镁、钙、总蛋白、胆固醇、血糖及甘油三酯的含量与Ⅱ组比较均见P〉0.05,无统计学意义;在Ⅰ组中,唇裂伴腭裂者与单纯唇裂者母体血清的各种营养物质含量比较均见P〉0.05,无统计学意义。结论唇腭裂的发生与孕期母体的营养状况有一定关系,其中锌含量的高低与后代唇腭裂的发生密切相关。     

Determining the epidemiologic,outcome, and prognostic factors of oral malignant melanoma by using the Surveillance,Epidemiology, and End Results database

Background

The authors conducted a retrospective analysis to determine the epidemiologic, outcome, and prognostic factors in patients with oral malignant melanoma (OMM).

Bisphosphonates, osteonecrosis of the jaw, and dental treatment recommendations

Millions of patients in the United States take bisphosphonates for management of malignant bone metastases, osteoporosis, osteitis deformans (Paget's disease), and osteogenesis imperfecta. Since 2003, over 200 cases of osteonecrosis of the jaws have been described, mostly in patients with multiple myeloma or breast cancer patients, and to a lesser extent in patients on oral medications.     

Full coverage, partial coverage, and the role of pins

The indications, advantages, and disadvantages of various types of restorations and retainers have been discussed. The proper use of pins makes it possible to use conservative partial coverage in many teeth. For badly broken down teeth, the proper use of full coverage is the only successful method of treatment.