c-myc oncoprotein expression in oral precancerous and early cancerous lesions.

Squamous cell carcinoma of the oral cavity is often preceded by clinically evident precancerous lesions. These lesions exhibit progressive cytomorphologic changes connoting cellular transformation to malignant neoplasia. Molecular events underlie the microscopically identifiable cytological changes that herald transformation.

The effects of streptomycin/lidocaine block on trigeminal neuralgia: a double blind crossover placebo controlled study.

This study investigated the long term effect of a peripheral sensory block using streptomycin sulphate on trigeminal neuralgia. A total of twenty subjects, thirteen with idiopathic trigeminal neuralgia (ITN) and seven with traumatic trigeminal neuralgia (TTN) were studied. A double-blind placebo controlled randomized design was used.

In vitro antimicrobial activity of the human neutrophil cytosolic S-100 protein complex, calprotectin, against Capnocytophaga sputigena.

Calprotectin is a complex of two anionic proteins found in abundance in the cytosol of neutrophils, certain macrophages, and oral epithelial keratinocytes. Bacteria of the genus Capnocytophaga are pathogens of periodontal origin which can cause systemic infection in neutropenic subjects. Recently, it has been observed that Capnocytophaga may be internalized by neutrophils within the cytosol rather than within a membrane-delimited phagosome.

Thermographic characterization of the asymptomatic temporomandibular joint.

This study used electronic thermography, an alternative diagnostic imaging modality, to assess the thermal image characteristics of the normal TMJ in 30 asymptomatic subjects. Assessments made included: thermal pattern recognition and symmetry, absolute temperature measurements and differences in absolute temperature measurements, and mean temperature measurements and differences in five anatomic zones. Results indicated the presence of a common thermal TMJ pattern in two thirds of patients, with variations from this pattern in the remaining patients.

The degree to which attrition characterizes differentiated patient groups of temporomandibular disorders.

Dental attrition severity as the cumulative record of parafunctional and functional wear was graded from study cast analysis using established methodology. Attrition severity was compared in anterior, posterior mediotrusive, and posterior laterotrusive segments. Attrition scores in 48 female and 100 male totally asymptomatic controls were compared to 239 female and 31 male patients differentiated into five patient groups of temporomandibular disorders: (1) disc displacement with reduction, (2) disc displacement without reduction, (3) osteoarthrosis with a history of prior derangement, (4) osteoarthrosis without a history of prior derangement, and (5) myalgia only.

Evaluation of a clinical recovery score after general anesthesia.

A clinical recovery score (CRS) assessing recovery after general anesthesia was compared with the Digit-Symbol Substitution Test (DSST), Trieger Test (TT), a patient-completed visual analogue scale for alertness (VAS), and an independent observer's evaluation of recovery. The CRS included ratings of the following parameters: activity, respiration, circulation, consciousness, ambulation, color, and nausea and vomiting. Forty patients requiring the removal of three or four third molars participated in the study.

Shape changes due to functional appliances.

Functional appliances are now routinely used in orthodontic treatment to correct anteroposterior skeletal discrepancies, based on the assumption that existing functional patterns can be modified to yield a new morphological pattern. However, the mechanisms by which this correction occurs remain in dispute as current measurement procedures, primarily mathematical, do not adequately describe shape changes. This paper introduces a new measurement method, Fourier descriptors, to clinical dentistry.

Human neutrophil azurocidin synergizes with leukocyte elastase and cathepsin G in the killing of Capnocytophaga sputigena.

Azurocidin was purified in the presence of phenylmethylsulfonyl fluoride. Electrophoresis revealed at least seven species which exhibited N-terminal sequences consistent with azurocidin. Azurocidin exhibited no bactericidal activity against Capnocytophaga sputigena or other oral bacteria but synergized the bactericidal activity of enzymatically active elastase.

Sequential combined tumorigenic effect of HPV-16 and chemical carcinogens.

We immortalized oral keratinocytes by transfection with recombinant human papillomavirus type 16 (HPV-16) DNA and established two cell lines, human oral keratinocytes-16A (HOK-16A) and -16B (HOK-16B). These cell lines were morphologically different from the normal counterpart, contained HPV-16 DNA as integrated form and expressed numerous viral genes. However, these cells proliferated only in culture medium containing low calcium (0.

Patch-clamp study of postnatal development of CA1 neurons in rat hippocampal slices: membrane excitability and K+ currents.

1. The postnatal development of membrane properties and outward K+ currents in CA1 neurons in rat hippocampal slices was studied with the use of whole-cell patch-clamp techniques. 2.

Biomechanical validation of the solitary lag screw technique for reducing mandibular angle fractures.

The purpose of this study was to determine whether the solitary lag screw technique meets the biomechanical demands of angle fractures. Simulated angle fractures in four cadaveric mandibles were reduced using solitary lag screws and the load-displacement relationships determined under functional loading of the individual mandibles. Subsequently, an angle fracture in a photoelastic mandible analog was fixed with a lag screw and subjected to similar loading.

Orthognathic diagnosis and treatment planning: a cephalometric approach.

Cephalometric analyses have long been important diagnostic tools for the orthodontic specialist. Such analyses, as they pertain to adult skeletal problems and their consequent therapy, should also be a valuable adjunct for various dental specialties, e.g.

Differential killing of Actinobacillus actinomycetemcomitans and Capnocytophaga spp. by human neutrophil granule components.

The purpose of this study was to determine whether granule fractions of human neutrophils differentially kill Actinobacillus actinomycetemcomitans and Capnocytophaga spp. Granule extracts were subjected to gel filtration, and seven fractions (designated A through G) were obtained. Under aerobic conditions at pH 7.

Effect of Herpes simplex virus infection on the trigeminal jaw-opening reflex in guinea pigs.

Herpes simplex virus (HSV) infection induces numerous electrophysiological and microscopic changes in neurons in vitro. To investigate the effect of HSV infection on in vivo neuronal activity, we induced an acute, latent and reactivated HSV infection of the trigeminal ganglia of guinea pigs through orofacial HSV inoculation and studied its effect on the trigeminal jaw-opening reflex of anesthetized guinea pigs. During the acute viral infection period both the threshold for elicitation of the reflex, and the latency to the onset of the reflex response were increased.

Immortalization of normal human oral keratinocytes with type 16 human papillomavirus.

Primary human oral keratinocytes were transformed by transfection with recombinant human papillomavirus type 16 (HPV-16) DNA, and two transformed cell lines named human oral keratinocytes-16A and -16B (HOK-16A and HOK-16B) were established. While normal cells and cells transfected with vector only exhibited a limited lifespan, the HOK-16A and HOK-16B lines demonstrated immortality and altered morphology from their normal counterpart. The HOK-16A and HOK-16B lines contained approximately 40 and approximately 25 copies of intact HPV-16 DNA as integrated form per cell respectively, and both cell lines expressed several viral specific poly(A+) RNAs.

Healing and repair of osseous defects.

This article has discussed most of the modalities currently in use for the filling of bony defects. No one modality or combination of methods or materials has yet surfaced as the definitive means of treatment for filling these defects.

Electronic thermography in the assessment of internal derangement of the temporomandibular joint. A pilot study.

Current diagnostic imaging methods to evaluate internal derangement of the temporomandibular joint (TMJ) include arthrotomography, arthroscopy, computed tomography, and magnetic resonance imaging. Most of these techniques either require ionizing radiation or are invasive, and all are expensive. Electronic thermography (ET) is an alternative diagnostic imaging modality that is inexpensive, nonionizing, and noninvasive.

Synergism of herpes simplex virus and tobacco-specific N'-nitrosamines in cell transformation.

Previous studies indicate that herpes simplex virus (HSV) enhances the carcinogenic activity of smokeless tobacco and tobacco-related chemical carcinogens in animals. Since tobacco-specific N'-nitrosamines (TSNAs) such as N'-nitrosonornicotine (NNN) and 4-(N-methyl-N'-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) are major chemical carcinogens of smokeless tobacco and are known to be responsible for the development of oral cancers in smokeless tobacco users, the combined effects of TSNAs and HSV in cell transformation were investigated. Exposure of cells to NNN or NNK followed by virus infection resulted in a significant enhancement of transformation frequency when compared with that observed with chemical carcinogens or virus alone.

Anchorage-independent growth and the expression of cellular proto-oncogenes in normal human epidermal keratinocytes and in human squamous cell carcinoma cell lines.

The expression of multiple cellular proto-oncogenes and the in vitro anchorage-independent growth of normal human epidermal keratinocytes and several human squamous cell carcinoma cell lines were studied and correlated. Squamous cell carcinoma cell lines KB, Si Ha, HEp-2, and Fa Du showed high anchorage independency, and MS 751 and A-253 cell lines had minimum independency. However, the normal keratinocytes and the A-431 cell line did not show anchorage-independent growth.

An esthetic titanium abutment: report of a technique.

New esthetic two-piece titanium abutment cylinders have recently been introduced for the Brånemark implant system. The conical design allows for the fabrication of fixed partial dentures with improved esthetics compared to the conventional abutment design. The improved feature provides for the ability to begin the restoration closer to the implant while still maintaining a titanium/soft-tissue interface.

In vitro sensitivity of oral, gram-negative, facultative bacteria to the bactericidal activity of human neutrophil defensins.

Neutrophils play a major role in defending the periodontium against infection by oral, gram-negative, facultative bacteria, such as Actinobacillus actinomycetemcomitans, Eikenella corrodens, and Capnocytophaga spp. We examined the sensitivity of these bacteria to a mixture of low-molecular-weight peptides and highly purified individual defensin peptides (HNP-1, HNP-2, and HNP-3) isolated from human neutrophils. Whereas the Capnocytophaga spp.

Development of the Geriatric Oral Health Assessment Index.

The development of measures for assessing oral health status is essential to the evolution and maturation of a scientific knowledge base in geriatric dentistry. The literature suggests a high prevalence of dental diseases in older adults, yet valid and reliable instruments to assess the impact of oral diseases on older individuals or populations are lacking. This paper describes the rationale for and the development of the Geriatric Oral Health Assessment Index (GOHAI), a self-reported measure designed to assess the oral health problems of older adults.

Preferential adsorption of human neutrophil myeloperoxidase isoform III by oral bacteria.

Neutrophil myeloperoxidase (MPO) adsorbs to bacteria as a pre-requisite for killing by the MPO/hydrogen-peroxide/chloride system. Three chromatographically distinct isoforms of MPO (MPO I, MPO II, and MPO III) have been isolated from human neutrophils. The purpose of this study was to determine whether oral bacteria--including Actinobacillus actinomycetemcomitans, Capnocytophaga sputigena, Haemophilus aphrophilus, and Eikenella corrodens--differentially adsorb the three major isoforms of MPO from a mixture of MPO I, II, and III, and to assess the effect of pH and normal human serum (NHS) on MPO adsorption.

Physical medicine procedures affect temporomandibular disorders: a review.

This article reviews the literature on the effectiveness of physical medicine procedures for treatment of temporomandibular disorders (TMD). Brief descriptions of some commonly used dental appliances, and pharmacological and surgical treatment methods are provided.