Ridge Preservation in Asian and Caucasian patients
“These patients will lose much alveolar bone if we do nothing.” Interview conducted by Verena Vermeulen
Thin vs thick biotypes, tooth-root angulation – what are the differences between socket anatomy in Asian and Caucasian patients? And what do these differences mean for implant placement? We talked with three experts from two continents about small differences with big impacts. Dr. Araújo, you are one of the first investigators of the sequence of biological events after tooth extraction. In brief, what happens? Dr. Araújo: The healing process is divided into three phases: inflammatory, proliferative and modeling/remodeling. In the last phase, the osteoclast activity promotes extensive bone resorption that reduces the alveolar ridge dimension. Facial bony walls are frequently thinner than 1 mm, and these thin walls are almost exclusively bundle bone.1 Because it is a completely tooth-dependent structure, the bundle bone is resorbed after tooth extraction.
“In the esthetic zone, 30 % of the volume of the alveolar ridge is lost.” Dr. Mauricio G. Araújo
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GEISTLICH NEWS 2-2021
How much volume is lost on average? There are so many studies, site-specific factors, measurement points and methods… do you have an easy answer? Dr. Araújo: On average, in the esthetic zone, about 50 % of the width and 30 % of the volume of the alveolar ridge is lost.2 This amount is very significant.
Is the process of bone resorption similar in all patients and sites? Dr. Araújo: The process is the same in all patients, but the clinical outcome is different. A thin buccal bone wall, a narrow alveolar socket and a socket outside the bone envelope may significantly increase the volume loss.
Dr. Yeo, you investigated one of these conditions that affect bone resorption after tooth extraction in more detail: tooth-alveolus angulation. What does this term mean? Dr. Yeo: Tooth-alveolus angulation is the angle measured where the axial planes of tooth-root and the alveolus converge (Fig. 1). A small angle suggests that the entire tooth-root is expected to be positioned within the alveolar housing. In case of a large angle, the root will be positioned very close to the buccal bone wall or even out of the buccal aspect of the alveolar housing.
How frequent is this condition? Dr. Yeo: To the best of my knowledge, we have many reports of angulation issues
