Linear and volumetric analysis on the effect of a customized healing abutment at maxillary immediate implant sites

Abstract

Introduction: The placement of immediate post-extraction implants is a frequent
treatment modality in clinical practice, and the processes that are involved in the
healing of the alveolar are being investigated, taking into account that the
inevitability of physiological remodeling phenomena after tooth extraction can
result in significant changes in alveolar bone. The aim of this study is to compare the clinical differences determined through tissue changes between two types of alveolar sealing after placement of an immediate implant in the maxillary arch over two years of treatment. Materials and Methods: The present study followed a methodology of prospective, controlled, randomized clinical study with parallelism of test groups. The treatment protocol was randomly divided according to the alveolus closure technique used. Thus, in group I, patients who had the post-extractional alveolus sealed with a reabsorbable matrix of collagen sutured through a simple suture interrupted with polyamide thread 6/0 to the adjacent alveolar mucosa were allocated; patients in group II received a customized healing abutment, without the need for sutures. All patients were rehabilitated prostheticly and provisionally, with Maryland crown
type. Ten days after the surgical procedure, the sutures of group I were removed
and scheduled the postoperative controls, which included visits to one (T1), four
(T2), twelve (T3) and twenty-four (T4) months after implant insertion. The digital
models of the arch in question corresponding to T1, T2, T3 and T4 were exported from the intraoral optical scanner software used in STL format and imported into the computer program, following the analysis protocol of already published models. The mean values were compared and the statistical significance was established at 0.05. Results: Thirty-four patients participated in this study, with a mean age of 53.38±11.46 years. No patient was diagnosed with periodontal disease during the 24-month follow-up period. In group I, most tissue changes occurred during the first (T0-T1), fourth (T0-T2) and twelfth month of observation (T0-T3) in comparison with twenty-four months (T0-T4). These results are not significant to a 1 year of follow-up in relation to variations in linear measurements and volumetric measurements. Regarding the variation in vestibular volume, the alterations occurred in the two years of follow-up (T0-T4) individuals in group I had an average loss of -8.53%±6.51 and individuals in group II of -12.00%±7.09, with significant differences between the two groups. Conclusion: The group of patients who received the collagen membrane had favorable results over the two years of treatment in the maintenance of peri-implant tissues in relation to the customized abutment.

Date of Award	23 Jul 2021
Original language	Portuguese
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Tiago Borges (Supervisor) & Bruno Almeida (Co-Supervisor)