Assessment of Alveolar Ridge Dimensions and Bone Quality

Assessment of Alveolar Ridge Dimensions and Bone Quality

Introduction

Alveolar bone is called the bone of the jaw containing coated basins or alveoli, which are retained in the roots of the teeth. It is a thin, compact bone with multiple small pores containing vessels through which pass the blood flow is facilitated; moreover, it also contains several nerves and lymphatics. Alveolar bone either from the maxilla or mandible is linked with the roots of teeth. Within the bone there are small craters that mark the place where the teeth are inserted. These spaces are known as the alveoli and its walls are called alveolar processes. The walls of the alveoli, in contact with the periodontal ligament, are coated with compact bone structures, while the area between the alveoli is occupied by cancellous bone (trabecular). The alveolar bone is constantly renewed in response to functional needs: thus, when a tooth is lost, or to be more precise when the root of the tooth is lost, the alveolar bone no longer performs its function of support. The purpose of this paper is to enlighten and explore diverse assessment methods of alveolar ridge dimensions and bone quality. This paper aims to explore different approaches ranging from traditional to contemporary methods of alveolar assessment in order to explain the optimal approach that must be selected in the process.

Conventional (Radiographic) Imaging

There are several important application areas where the only practical way to acquire two-dimensional or three-dimensional images of an object is by using a set of image projections. For example, image reconstruction is an important requirement in medical imaging, geophysical exploration, underwater exploration, and radio astronomy. Image processing methods can be classified in two groups: spatial domain approaches and transform (or frequency) domain approaches. The spatial domain techniques work directly on the two-dimensional digital images [1]. The spatial domain approaches have intuitive appeal and are relatively easy to develop and implement. The transform domain techniques require an image to be transformed into another domain, using transformations derived from mathematical models. Characteristics of these transformed images are analyzed to accomplish a specific image processing task. Linear systems theory had allowed treatment of one-dimensional signals in both the time and frequency domains. Typically, results of the spatial domain analysis are easier to interpret than those of the frequency domain.

Invasive Measurement Technique

The invasive measurement technique consist different methods that are based on the principle of the attenuation of X-rays or gamma ray photons to pass through the bone tissues. Such assessment technique is related to the thickness and composition of the tissues through which the essential thickness of the bone and contained mineral can be assessed [2]. The attenuation values can be expressed in equivalent thickness of the alveolar ridge in order to compare them with curves based on the normal standard of assessment. The result through invasive measurement technique is expressed as standard deviations of normality curves. However, the value obtained through invasive measurement is a combined measurement of bone tissue, bone marrow ...