Immunocytochemical localization of growth hormone receptor in rat maxillary teeth.

To address the question of what role growth hormone may have in stimulating tooth formation, the distribution of its receptor/binding protein in developing rat incisors and molars was studied immunocytochemically using well-characterized monoclonal antibodies. Ten female 45-day-old Wistar rats were perfused with 4% paraformaldehyde. Five-microns paraffin sections of the growing end of maxillary incisors and molars were cut, deparaffinized and incubated with mouse anti-growth hormone receptor antibodies or control antibodies. A three-layer streptavidin peroxidase technique was used to detect bound antibody. Immunoreaction product was associated primarily with the cytoplasm of cells at certain stages of differentiation. Dividing cells, differentiating preameloblasts and preodontoblasts, secretory ameloblasts and odontoblasts showed immunoreactivity. Undifferentiated dental epithelium cells, stellate reticulum, external dental epithelial cells, mature odontoblasts, and most of cells in the dental papilla were non-reactive. However, at certain stages of tooth development, the stratum intermedium and the external dental epithelium also stained positively. The presence of growth hormone receptor/binding protein in tooth cells at different stages of their development indicates that growth hormone may influence cell proliferation, differentiation and differentiated functions of ameloblasts, odontoblasts and cementoblasts independent of a systemic mediator, and thus may be involved in stimulating odontogenesis directly.     

Commissure Burn Splints: Literature Review and Prefabrication Technique Using a Visible Light–Cured Resin

Commissure burn splints reduce or eliminate the need for reconstructive surgery after injury to the perioral tissues. The literature describes the injury, immediate care, and splint treatment modalities. A technique to construct a prefabricated commissure burn splint from visible light cure resin and orthodontic wire is presented. Passive or dynamic retraction may be obtained by varying the tension of circumcranial orthodontic headgear or adjusting Velcro placed on a Velfoam strap.     

Root substance removal by scaling and root planing.

The amount of root substance removed by scaling and root planing is largely unknown. The present study evaluated in vitro the root substance loss caused by a defined number of working strokes at known forces. Forty extracted teeth with loss of connective tissue attachment into the middle third of the roots were washed and embedded in plaster, leaving one entire corono-apical tooth aspect exposed. The teeth were reproducibly repositioned in a bench-vise, where a profilometer repeatedly measured root surface levels at the same location. In a standard area of the roots a total of 40 working strokes were applied. Low forces were used in 30 teeth and high forces in 10 teeth. The forces were recorded using a piezo-electric receiver built into the upper shank of the curet. Root substance loss was measured after 5, 10, 20, and 40 working strokes. The results showed that the mean low force used per working stroke across all 40 strokes was 3.04 Newtons for the low forces, and 8.48 Newtons for the high forces. Mean cumulative loss of root substance across 40 strokes was 148.7 microns at low forces, and 343.3 microns at high forces. The mean force per stroke increased slightly across the 40 strokes, while substance removal per stroke decreased. Substance removal per stroke during strokes 1 to 5 was 6.8 microns using low forces and 20.6 microns using high forces. During strokes 21 to 40 mean removal per stroke was 2.3 microns at low forces, and 5.6 microns at high forces. These results suggest that high forces remove more root substance, and loss per stroke becomes less with increasing numbers of strokes.     

Review of the literature and report of a case of a dermoid cyst.

This article presents a large dermoid cyst discovered in the floor of the mouth of a young male patient. The lesion was clinically detected by manual palpation and confirmed by the use of magnetic resonance imaging. Treatment of this case was by surgical removal of the dermoid cyst. The patient recovered without any complications or evidence of re-occurrence of the cyst.     

Colorimetric changes in composites resulting from visible-light-initiated polymerization

We evaluated three shades of nine light-cured composites to determine the colorimetric changes which occur as a result of the photo-polymerization reaction. A photo-electric tristimulus colorimeter was used to measure the color of a 0.5-mm-thick sample of composite on two different backgrounds before and after the polymerization process had been initiated. The results showed that each of the photo-initiated composites tested produced a visually significant change in color as a result of the polymerization reaction, regardless of the shade of the backing. In general, the light-cured composites produced a characteristic chromatic shift toward the blue region of color space, which resulted in a perceived decrease in yellow chroma. Therefore, direct shade selection of a resin composite which is more yellow or more chromatic than the tooth which is being restored is recommended to compensate for this characteristic immediate color shift.     

Sequencing LeFort fracture treatment (Organization of treatment for a panfacial fracture)

The types of midfacial fractures and their complexity were evaluated in admissions to the Maryland Institute of Emergency Medical Service Systems (MIEMSS) during the years of 1984 to 1988. Two hundred and sixty-eight LeFort fractures were treated and followed (3.2 percent of admissions). One half (50 percent) had skull fractures and 40 patients (15 percent) had LeFort, skull and mandibular fractures. Isolated nasoethmoidal fractures were observed in 176 patients and in 107 patients (39 percent) of patients with LeFort fractures. Isolated mandibular fractures were observed in 321 patients and in 104 patients with LeFort fractures (39 percent). Eleven percent of patients had midfacial, nasoethmoidal and frontal sinus fractures. Six percent of patients had midfacial, frontal bone, frontal sinus and nasoethmoidal fractures (Cranial Base Crush Syndrome). Twenty two percent of patients had LeFort and frontal sinus fractures. Reconstruction of multiple area injuries is simplified by a highly organized treatment sequence that conceptualizes the face in two groups of two units. Each unit is divided into sections, and each section is assembled in three dimensions. Sections are integrated into units and units into a single reconstruction. Conceptually, in each unit, facial width must first be controlled by orientation from cranial base landmarks. Projection is then (and often reciprocally with width) established. Finally, facial length is set both in individual units and in the upper and lower face. Soft tissue is considered the "fourth dimension" of facial reconstruction. Bone reconstruction should be completed as early as possible to minimize soft tissue shrinkage, stiffness and scarring of soft tissues in nonantomic positions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Type 2 diabetes mellitus and periodontal disease

The relationship between type 2 diabetes mellitus and periodontal disease was evaluated in 2,878 Pima Indians of the southwestern United States. Two independent measures of periodontal disease, probing attachment loss and radiographic bone loss, were used to compare prevalence and severity of periodontal disease in diabetic and nondiabetic subjects. In all age groups studied, subjects with diabetes had a higher prevalence of periodontal disease, indicating that diabetes may be a risk factor for periodontal disease.     

Evaluating and influencing periodontal diagnostic and treatment behaviors in general practice

Providers' periodontal diagnostic and treatment behaviors were assessed in 34 practices in two North Carolina counties. Regularly attending patients had a low prevalence of gingival pocketing on index teeth, moderate attachment loss, and fairly prevalent bleeding and calculus. Treatment frequency and patient knowledge were generally adequate, but the notation of periodontal status in the patient record was insufficient. A continuing education intervention resulted in substantial and significant improvement in notation rates. Changes in rates with which services were provided, and changes in patient periodontal status were smaller and mixed. The study shows that continuing education can be effective in helping some but not all providers adopt needed, appropriate behaviors.     

Osseo-integrated implant treatment of a patient with rapidly progressive periodontitis. A case report

The case report presented describes placement of osseointegrated fixtures in a patient with a probable history of rapidly progressive periodontitis. A 12-year history is presented. The post-operative sequelae of placing fixtures in a fully edentulous maxilla and partially edentulous mandible were the worst seen by the Implant Team at Emory University. The hypothesis presented is that patients with aggressive forms of periodontal disease should be subjected to appropriate mechanical and antimicrobial therapy to produce a healthy oral flora before any implants are placed.