01 June 2021

---

Preserve the alveolar ridge after a dental extraction

Lara Figini

---

The extraction of a dental element, in addition to having a direct impact on the quality of life, initiates a cascade of biological events resulting from alterations in the homeostasis and structural configuration of existing periodontal tissues, leading to progressive alveolar ridge atrophy, as demonstrated in the clinical studies by Chappuis et al. 2015; and Disciples et al. 2013. This physiological phenomenon was mainly attributed to the local inflammatory response following a surgical trauma, which involves a transient upregulation of osteoclastogenesis, combined with a complete deprivation of the biomechanical stimulation of the alveolar bone. Volume deficiencies of the alveolar ridge can interfere with subsequent tooth replacement therapy using fixed dental prostheses, or with implant-supported restorations.

Materials and methods
In a recent randomized controlled study, published in the Journal or Dental Research of April 2020, the authors evaluated the efficacy of ARP alveolar ridge preservation therapy with respect to unassisted healing of the post-extraction socket. A secondary objective was to evaluate the local phenotypic effect and the factors that play an important role in the volumetric reduction of the alveolar bone. A total of 53 subjects completed the study. Subjects were randomly assigned to either the control group, which involved only tooth extraction (EXT n = 27), or the experimental group, which performed tooth extraction using ridge-preserving therapy. ARP alveolar, with a technique that involves the combination of a graft with a particular particle bone filler and sealing with a non-absorbable membrane (dPTFE) (ARP Group n = 26) in the post-extraction alveolus. A range of clinical, linear, volumetric, and patient-reported outcomes were evaluated over the subsequent 14-week healing period.

Results
All linear bone assessments (horizontal, mesio-buccal and mesio-lingual reduction) were better in the ARP group than in the EXT group. Volumetric bone resorption was also significantly higher in the control group (mean ± SD: EXT = -, 8.83% ± 4.48%, ARP = -8.36% ± 3.81%, P <0, 0001). Linear regression analyzes revealed that vestibular bone thickness at baseline time is a strong predictor of alveolar bone resorption in both groups. No significant differences were observed in terms of soft tissue contour alteration in either group. An additional bone augmentation was deemed necessary to facilitate implant placement in a prosthetically acceptable position in 48.1% of the post-extraction sites in the EXT group and only in 11.5% of the post-extraction sites in the ARP group. The evaluation of the postoperative discomfort perceived by the patients at each follow-up visit revealed a progressive decrease over time of the same, comparable between the groups.

Conclusions
From the data emerging from this randomized study, which must be confirmed in other similar studies, it can be concluded that ARP therapy ensures more effective maintenance of alveolar bone after tooth extraction, reducing the estimated need for further bone augmentation at the time of implant placement.

For additional information: Efficacy of Alveolar Ridge Preservation: A Randomized Controlled Trial