Clinical and radiographic assessment of the efficiency of the application of autologous dentin graft in cases of surgical extraction of impacted lower third molars

Abstract

Summary. Nowadays, the question of bone defects healing optimization after surgical removal of impacted third molars remains extremely relevant. The technology of manufacturing and clinical application of autologous dentin graft (ADG), proposed recently by foreign specialists, allows a new approach to solving the above-mentioned problem.

The aim of the study – to conduct biometric and densitometric assessment of autologous dentin graft used to replace residual bone cavities after surgical removal of impacted lower third molars.

Materials and methods. Clinical assesment and surgical treatment of 16 patients (10 women and 6 men aged 25.2±7.0 years) with impaction of lower third molars, as well as complications of caries and pericoronaritis of the lower third molars was conducted. The patients were divided into two groups: The main group (9 patients who underwent augmentation of post-extraction defects using ADG) and the control group (7 patients whose post-extraction defects were to be healed under a blood clot). Preparation of ADG from extracted teeth in patients of the main group took place in the operating room during the operation using the Smart Dentin Grinder (KometaBio, USA) device, followed by sterilization with an alcohol solution and neutralization with a phosphate buffer solution according to the recommended protocol. It is important to notice that only extracted teeth that were not endodontically treated underwent processing. In none of the cases were factory-made resorbable or non-resorbable membranes used for isolation of substitution material. Follow-up clinical assesments were scheduled for days 1, 3, 8–10 after surgery. In the postoperative period, all patients were prescribed the same anti-inflammatory and symptomatic medication and the following assesments were conducted: establishing the terms of complete epithelization of the wound and removal of sutures; measurement of the depth of the periodontal defect behind the second molar – the distance between the occlusal plane and the top of the alveolar crest at the level of the middle of the crown using a graduated periodontal probe, radiological methods of research (radiography, cone-beam computed tomography in order to determine the level of bone tissue loss horizontally by measuring the distance between the vestibular and lingual cortical plates at the level of the middle of the defect ("Veraviewepocs 3D R100" (J. Morita Manufacturing Corporation, Japan))), determination of the mineral density of bone tissue in the area of the defect using the i-Dixel 2.1 CT viewing software ( 3, 6 month follow-up).

Results and Discussion. The terms of complete epithelization of the wound and removal of sutures were faster in patients of the main group (8.56±0.72 days) compared to patients in the control group (10.13±0.5 days) (p<0.05), which may indicate mediated effect of growth factors contained in ADG on the healing of soft tissues. The depth of the periodontal pocket behind the second molar was significantly less (p<0.05) in patients of the main group both on the 3rd (3.6±1.09mm; 3.7±1.15mm) and on the 6th (2.54±0.73mm; 2.68±1.03mm) month postoperatively, compared to patients of the control group (4.02±1.28mm; 3.81±1.22mm and 3.76±1.55mm; 3.24±1.71mm, respectively). The level of horizontal bone tissue loss, measured on CBCT scans, was significantly different (р<0.05) among patients of the main and control groups, both on the 3rd (10.80±0.65mm vs. 8.13±0.40mm respectively) and on the 6th month after surgery (10.42±0.71mm vs. 6.98±0.84mm respectively). As of the 3rd month after surgery, significant statistical differences were found in bone density indicators in the area of post-extraction defects in patients of the treatment group (661.34±44.90 HU) and control (372.57±67.28 HU) (p<0.001) . At the 6th month of follow-up, the above-mentioned trend was maintained: the bone density indicators were fixed at the level of 914.5±58.35 HU in patients of the treatment group, which corresponded to the level of the adjacent corticalized areas, while in patients of the control group, this indicator was half as low (581.38±74.22 HU). A clinical case of a 22-year-old patient with horizontal impaction of tooth 38, partial resorption of bone tissue behind the distal root of tooth 37, whose post-extraction defect was replaced with ADG, was presented.

Conclusions. The use of patient’s own extracted impacted teeth in the form of dentine granulate in order to replace post-extraction defects helps minimize bone and tissue loss in the area of the operation, prevents formation of periodontal pockets behind the second molar, and accelerates the process of bone tissue formation with optimal mineral density in the area of the bone defect.