Healing Abutment Distortion in Implant Prostheses: An In Vitro Study

Abstract

Little has been studied regarding the repeated usage of healing abutments and their effects on the distortion of dental implant-healing abutment hex surfaces. Additionally, implant manufacturers do not provide specific guidelines on how many times a healing abutment can be used before discarding. Therefore, we evaluated the effect of repeated screwing-unscrewing of implant-healing abutment on the healing abutment hex surface and screw head. A total of 12 Biomate implants with 4 mm diameter and 13 mm length were inserted into a synthetic bone block. The standard healing abutments of 3 mm diameter and 4 mm length were screwed onto each implant using a torque ratchet at a final torque of 30 Ncm. Immediately, the abutments were unscrewed at 30 Ncm. Then, screwing-unscrewing was repeated for 4, 8, 16, 24, 32, 40, 80, 160, 320, and 400 times and the healing abutments were scanned under the scanning electron microscope for any distortion. Distortion was graded as 0, 1, 2, and 3. Data were analyzed using SPSS 24.0. Descriptive statistics were calculated. One-way ANOVA with post hoc using Tukey’s HSD test was performed to analyze the difference in distortion at different screwing-unscrewing times. A significant level was selected at p-value = 0.05. It was found that distortion healing abutments screws were seen after 32 times screwing and unscrewing. There was a significant difference in the distortion (p-value < 0.05) after 24 times of repeated usage of healing abutment and at 160, 320, and 400 times. No surface distortions were observed at the healing abutment screw head at 4, 8, 16, 24, 32, 40, 80, 160, 320, and 400 cycles of screwing-unscrewing. It can be concluded that repeated screwing and unscrewing of the implant-healing abutments causes damage to the healing abutment hex surface. The distortion of healing abutments screws was seen after 32 times screwing and unscrewing. No surface distortions were observed on the healing abutment screw head until 400 times of screwing and unscrewing. Hence, the clinician should be cautious while using the healing abutments repeatedly.

Evaluation of Prosthetic Marginal Fit and Implant Survival Rates for Conventional and Digital Workflows in Full-Arch Immediate Loading Rehabilitations: A Retrospective Clinical Study

“…However, screw-retention is considered the best option by the authors for full-arch implant-supported restorations, since it facilitates the detection and management of possible complications, prosthesis relining and avoids the risk of cement-induced periimplantitis [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. It is relevant to notice that the prosthetic framework is connected to the abutments, which are screwed onto the implants at the time of surgery; therefore, the possibility of complication and/or deformation of the internal connection of the implants, as described by Pandey C. in 2022, is not relevant when this technique is used [24]. Some limits of the present research must be acknowledged.…”

A novel technique to retrieve a cold welded gingival former- A Technical note

“…This incidence of cold welding of the gingival former can be prevented by taking certain precautions such as application of petroleum jelly or antibiotic ointment on contacting surfaces, thorough irrigation to avoid blood contamination and bone debris wedged between threads and application of chlorhexidine gel inside implant. [6][7][8][9][10]…”