Normal anatomy on tomograms for dental implants.

Some dentists may be unfamiliar with reading conventional tomograms made of dental implant sites. The purpose of this article is to aid dentists in identifying normal anatomical landmarks on cross-sectional slices and to correlate them to sagittal slices.

Evaluation of hard tissue replacement composite graft material as a ridge preservation/augmentation material in conjunction with immediate hydroxyapatite-coated dental implants.

Background: Immediate placement of dental implants (DI) in fresh extraction sockets is associated with remaining voids around the DI and often a partial dehiscence or thin facial alveolar plate. Bone replacement grafts are often used to correct these problems. This study evaluated the use of a layered composite of PMMA (poly-methyl-methacrylate), PHEMA (poly-hydroxyl-ethyl-methacrylate), and calcium hydroxide grafts (HTR) as a ridge preservation/ augmentation material used in conjunction with an immediate DI placement technique.

An illustrative study of the role of tomograms for the placement of dental implants.

Before dental implants are placed, an evaluation of a presurgical bone site with tomograms will reveal information not available from panoramic or periapical radiographs. This article illustrates the importance of making tomograms before the placement of dental implants to determine the actual height, width, inclination, and undercut of alveolar bone; the shape, cortication, and irregularities of crestal alveolar bone; the density of alveolar bone; the relative location of anatomical landmarks, such as mandibular canal, maxillary sinus, nasal fossa, incisive canal, submandibular gland fossa, etc.; the bucco-lingual view of dental pathosis; the bucco-lingual evaluation of sinus graft following sinus-lift surgery; and the evaluation of surgically placed dental implants.

Effect of over- and underexposure on the sharpness of the image of a marker in computer-assisted dental implant tomography.

In dental implant tomography, a clinician typically makes several tomograms of cross-sectional and sagittal slices at and near the intended implantation site. The slice with the sharpest image of the metal marker is deemed to be the correct implantation site; the other slices with blurred images of the marker are those made either mesially or distally to the marker. However, if the images were over- or underexposed, the marker will be blurred on all the slices and a dentist may be wrongly accused of having placed a dental implant at an improper site with possible medico-legal ramifications.

Interrelationship between cross-sectional and sagittal imaging in computer-assisted dental implant tomography.

Objective: To determine what changes may occur in computer-assisted dental tomography to cross-sectional and sagittal slices when the positions of one or both slices are adjusted.

Methods: A human skull with a ball bearing attached to the mandibular first molar was positioned off-centre in a CommCAT (Imaging Sciences International, Hatfield, PA, USA) tomographic machine. An occlusal projection of the mandibular dental arch was scanned into the computer.

Differential diagnosis of pericoronal radiolucencies with and without radiopacities.

Pericoronal radiolucencies, by definition, surround the crown of a tooth. They are encountered not only in pediatric patients but also in adults of all ages. It is likely that all clinicians, at some time or another, will be confronted with a radiograph showing a pericoronal radiolucent lesion.

Everything you wanted to know about radiographic duplication.

If dental radiographs are not duplicated correctly, the resulting duplicates will be of inferior quality. This article discusses the characteristics of a duplicating film, the principle of radiographic duplication, a description of dental duplicators, the selection of optimum duplicating time, a technique of duplicating radiographs, an alternate technique of duplicating radiographs, errors in duplication and their correction, and the maintenance of duplicators.

Radiographic/surgical template incorporating metal telescopic tubes for accurate implant placement.

The dental literature is replete with information on various implant surgical template designs and imaging techniques for presurgical assessment of dental implant sites. Seldom are these two aspects combined in a practical and effective manner to fabricate a guide for precise implant placement. Unless detailed, three-dimensional images of the underlying bone are obtained, the use of a template is ineffective.

Diseases of the maxillary sinus.

Dentists often encounter patients whose signs and symptoms are not related to any dental disease, but rather originate in the maxillary sinuses. To distinguish when dental care is appropriate, dentists must be familiar with the anatomic, physiologic, clinical, and radiographic aspects of the maxillary sinuses.

Bone maintenance 5 to 10 years after sinus grafting.

Purpose: This radiographic study determined the amount of bone around hydroxyapatite (HA)-coated dental implants that were placed into bone-grafted maxillary sinuses.

Patients And Methods: Postoperative complex motion tomograms using the Grossman technique were taken on 16 patients who had 27 maxillary sinus grafts performed using particulate autogenous iliac bone with and without demineralized bone, autogenous iliac corticocancellous block with and without demineralized bone, and autogenous jaw bone with demineralized bone. Bone levels were measured from the new floor of the grafted sinus to the apex of the implant and to the alveolar crest.

Film-screen systems: sensitometric comparison of Kodak Ektavision system to Kodak T-Mat/RA system.

Background: In 1995, Eastman Kodak Company (Rochester, N.Y.) marketed the Ektavision Extraoral Imaging Film and Screen System.

Effects of tomographic motion, slice thickness, and object thickness on film density.

The experiment used the computer-aided CommCat model IS 2000 tomographic machine (Imaging Sciences International, Roebling, N.J.).

Effects of developer exhaustion on Kodak EKTASPEED Plus, Ektaspeed, and Ultra-speed dental films.

In 1994, Eastman Kodak Co. (Rochester, N.Y.

Sensitometric comparison of Kodak EKTASPEED Plus, Ektaspeed, and Ultra-speed Dental Films.

In 1994, Eastman Kodak Co. (Rochester, N.Y.

Sensitometric and archival evaluation of Kodak RA films in dental automatic processing.

The Kodak Rapid Access System is an extension of the T-grain technology (T-Mat film). Unlike the T-Mat film, the T-Mat/Rapid Access film is forehardened by the addition of more hardener to the film emulsion. It can thus be processed rapidly in a Kodak Rapid Access medical processor in only 45 seconds dry-to-dry cycle by using the Kodak X-Omat RA/30 developer that does not contain a hardener.

Sensitometric comparison of direct- and indirect-exposure films used in intraoral radiography.

In Japan, some dentists use indirect-exposure (screen) films for intraoral radiography, without the use of intensifying screens. The purpose of the present investigation was to determine whether film speed, inherent contrast, and latitude of Japanese indirect-exposure films used without intensifying screens were comparable to those of direct-exposure (non-screen) films used for intraoral radiography. The characteristic curves of Kodak Ektaspeed ("E" speed) and Ultra-speed ("D" speed) films were used as standards for comparison.

Automatic processing: effects of temperature and time changes on the sensitometric properties of light-sensitive films.

The effects of changes in the processing temperature and time of automatic processors were studied with three light-sensitive Kodak films: (1) blue-sensitive X-Omat RP film, (2) green-sensitive T-Mat G film, and (3) ultraviolet-sensitive X-Omat duplicating film. Speed and inherent contrast were derived for each of the three films from sensitometric curves at six different temperatures and at five different processing times. The T-Mat G film (T-grain technology) was comparatively less sensitive than conventional films (X-Omat RP) to increases in processing temperature or time.

Automatic processing: effects of temperature and time changes on sensitometric properties of ULTRA-SPEED and EKTASPEED films.

The effects of changes in the processing temperature and time of automatic processors were studied with Kodak ULTRA-SPEED and EKTASPEED dental x-ray films. Speeds and inherent contrasts were derived for the two films from sensitometric curves at seven different temperatures and at five different processing times. As opposed to manual processing, only a slight change in film fog was observed with increases in automatic processing temperature or time.