Inflammatory Impact on Tissues Surrounding the Dental Implant of Singular Abutments Bonded onto Titanium Base – A Randomized Controlled Trial

ABSTRACT

Introduction:

In dental implants, the biochemical connection between titanium (ti) and bony tissue has been well established. The properties of dental implants such as osseointegration and stability depend upon composition, design of the implant, connection, and design of the abutment, and additional removal of abutments. Recently, laser-generated micro-grooved surface (LSS) and TI abutments are the main focus of preventing peri-implant inflammation.

Objectives:

To assess the inflammatory impact of singular abutments bonded onto titanium bases on tissues surrounding the dental implant.

Methods:

Twenty subjects were enrolled. Only those subjects were enrolled who were scheduled to undergo prosthetic rehabilitation of missing teeth. Random division of subjects was done. Group A: Test abutment group and Group B: Control abutment group. The test abutments comprised Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) titanium abutments bonded onto titanium abutments. However, control abutments were customized and only one-piece CAD/CAM titanium abutments were enrolled.On 6 months and 12 months of follow-up, the clinical and radiographic examination was done. Assessment of the bone level changes, clinical variables, and IL-1b levels was assessed.

Results:

Mean IL-1b levels in Group A subjects at baseline, 6 months, and 12 months were 1.52 pg/mL, 1.69 pg/mL, and 1.55 pg/mL, respectively. Mean IL-1b levels among the patients of group B at baseline, 6 months, and 12 months were 1.56 pg/mL, 1.71 pg/mL, and 1.54 pg/mL, respectively.

Conclusion:

Within the limitation of the study, it can be concluded that the impact on the inflammatory condition of surrounding tissues of dental implant does not vary significantly between single abutments bonded onto Titanium bases and singular abutments.

INTRODUCTION

In dental implants, the biochemical connection between titanium (Ti) and bony tissue has been well established.[1] Numerous types of research have shown the link between Ti abutments and the tissue health of peri-implants.[2] There has been a smaller number of studies on the border formed between Ti and periosteum, musculoskeletal system, or layers of dura mater. Although, a deep study of the connection is more commonly acceptable to the surgical departments. In the maxillofacial surgery department, there is an advanced use of titanium. Ti alloys are not only for endosteal implants for replacing a missing tooth but also for bone grafts during facial contouring, prosthetic surgery, and subperiosteal oral reconstruction. Ti-based implants also present as transcutaneous implants.[3] Because of improvements in Ti 3-dimensional printing procedures, the applications of Ti in reconstructive procedures are expanding.[4]

The use of endosteal implants is for replacing lost teeth and also to support complete or partial dentures.[5] The properties of dental implants such as osseointegration and stability depend upon composition, design of the implant, connection and design of the abutment, and additional removal of abutments.[6,7] Role of soft-tissue attachment in peri-implant is to protect from contamination and thus prevent tissue infections.[8] Peri-implantitis are presenting with bone loss, bleeding on probing, and resulting in the loosening of the implant.[9] Recently, laser-generated micro-grooved surface (LMS) and Ti abutments are the main focus of preventing peri-implant inflammation. The connective tissue strongly adheres which leads to less inflammation and results in a decrease in marginal bone loss.[10,11]

Cytotoxicity in cultures of osteoblast cells which are exposed to metallic debris. Ti particles in implants act like foreign bodies and may lead to inflammation which results in bone resorption.[12] Research on the loosening of implants states that the secretion of preosteoclasts causes osteolysis, named “aseptic osteolysis.” This loosening of the implant imposes a severe threat to the health of peri-implant tissue.[13]

The objective of our study is to assess the inflammatory impact of singular abutments bonded onto titanium bases on tissues surrounding the dental implant. And the need for our study is to prevent peri-implantitis on tissues surrounding the dental implant.

MATERIALS AND METHODS

The current research aimed for assessing inflammatory effects on peri-implant tissue health as an abutment bonded onto a titanium base. Twenty subjects were enrolled. Only those subjects were enrolled who were scheduled to undergo prosthetic rehabilitation of missing teeth.

Inclusion criteria for the study were the presence of missing teeth to undergo prosthetic rehabilitation and Exclusion criteria included pregnant and lactation females and medically compromised patients.

Random division of subjects was done. Group A: Test abutment group and Group B: Control abutment group. The test abutments comprised CAD/CAM Ti abutments bonded onto Ti abutments. However, control abutments were customized and only one-piece CAD/CAM Ti abutments were enrolled. On 6 months and 12 months of follow-up, the clinical and radiographic examination was done. Assessment of the bone level changes, clinical variables, and IL-1β levels was assessed.

The following clinical parameters were available: (a) bleeding on probing (BoP) as measured within 60 s after probing and (b) probing depth (PD) as measured in mm from the mucosal margin to the bottom of the probable pocket. BoP and PD were assessed in six aspects around the implant: mesiobuccal, mid-buccal, distobuccal, mesio-oral, mid-oral, disto-oral.

Peri-implant crevicular fluid (PICF) was collected at the 6th month and 12th month postoperatively. A standardized volume of 3 μl PICF from the implant site in each patient was collected using calibrated, volumetric microcapillary pipettes positioned extracrevicularly on the margin of the gingiva and immediately transferred to an Eppendorf tube containing phosphate buffered solution and frozen at −70°C. Samples visibly contaminated with blood and saliva were discarded. The assay was then performed using an IL-1β ELISA test kit according to the manufacturer’s guidelines.

RESULTS

The mean age of subjects of group A and group B was 35.6 years and 37.1 years, respectively. The majority proportion of subjects of both study groups were males. Mean IL-1β levels among the patients of group A at baseline, 6 months, and 12 months were 1.52 pg/mL, 1.69 pg/mL, and 1.55 pg/mL, respectively. Significant results were obtained while comparing the mean IL-1β levels within group A at different time intervals. Mean IL-1β levels among the patients of group B at baseline, 6 months, and 12 months were 1.56 pg/mL, 1.71 pg/mL, and 1.54 pg/mL, respectively. Significant results were obtained while comparing the mean IL-1β levels within group B at different time intervals [Graph 1]. While comparing the crystal bone changes between the study group and the control group, nonsignificant results were obtained [Table 1].

Graph 1.

Comparison of mean IL-1β levels

Table 1.

Comparison of crestal bone levels changes

Crestal bone levels changes	Group A	Group B	Group C
Baseline to 6 months	0.87 mm	0.82 mm	0.4455
6 Months to 12 months	0.75 mm	0.78 mm	0.1485
Baseline to 12 months	1.62 mm	1.60 mm	0.2698

DISCUSSION

For the last 50 years, Ti has been known as a progressive implant material in dentistry. This is because of its biocompatible nature and static behavior. Nowadays, the Ti particles in mucosa have been revealed by various studies.[14] The salivary pH influences the corrosion rate of the Ti. Derks and Tomasi showed that the mean prevalence of peri-implantitis is 22% which is based on various types of research and large changes in the prevalence of the disease. They studied a large population and a random selection of samples with an assessment of radiographs of bone loss in the implants.[15-17]

Mean IL-1β levels among the patients of group A at baseline, 6 months, and 12 months were 1.52 pg/mL, 1.69 pg/mL, and 1.55 pg/mL, respectively. Mean IL-1β levels among the patients of group B at baseline, 6 months, and 12 months were 1.56 pg/mL, 1.71 pg/mL, and 1.54 pg/mL, respectively. A study by Rathe F et al.[18] showed the effects of Ti bases on which abutments were bonded. There was no significant difference in the bone level or clinical characteristics between test and control abutments. In both the groups, Il-1β levels were increased at 6 and 12 months on comparing to borderline.

While comparing the crestal bone changes between the study group and the control group, nonsignificant results were obtained. Another study by Linkevicius T et al.[19] studied the effect on the soft tissue of zirconia or Ti as abutment material. One of the studies depicted an increased pink esthetic score. All the research shows that there are no pros of Ti over Zr abutments or vice-versa. There is a superior esthetic outcome measured by the pink esthetic score for zirconia. Olmedo and co-workers[20] studied and detected Ti in soft tissues by EDX analysis. Paknejad and co-workers[21] studied biopsies of 96 subjects implants by EDX. They reported the existence of a correlation between the Ti ions and inflammation of the soft tissues. Many research articles concluded that titanium was present in soft tissues and they did not prove any link between Ti and inflammation.[22,23]

Pamato et al. also conducted where 52 implants were placed in 21 patients and restored by single crowns a study to evaluate the peri-implant soft tissue inflammatory parameters and crestal bone loss around titanium base abutments. They observed that the mean difference of peri-implant MBL from implant installation to 12 months in function was 1.15 ± 0.82 mm for the cement-retained group, and 1.23 ± 0.79 mm for the titanium base group. Similar to our study they also concluded that titanium base abutments present no negative effect on peri-implant soft tissue and MBL.[24]

There is a need to further evaluate the association of additional factors like necrosis of bone compression, bio-corrosion, and other multiple local factors in the future.

CONCLUSION

Significant results were obtained while comparing the mean IL-1β levels within groups at different time intervals. While comparing the crestal bone changes between the study group and the control group, non-significant results were obtained.

Within the limitation of the study, it can be concluded that the impact on the inflammatory condition of surrounding tissues of dental implant does not vary significantly between single abutments bonded onto Titanium bases and singular abutments.

Financial support and sponsorship

Department of Periodontology. Saraswati Dental College & Hospital. 233, Tiwariganj, Faizabad Road, P.O. Juggour (Via Chinhat) Lucknow - 227105 (U.P).

Conflicts of interest

There are no conflicts of interest.