A Comparative Study of the Flap and Flapless Techniques of Ridge Preservation: A Clinical Double-Blinded Study

ABSTRACT

Introduction:

Extraction of the tooth often leads to crestal bone loss. It is difficult for clinicians to decide on the technique of extraction. Many studies on flap and flapless have led to confusion. Hence it becomes necessary to conduct this study to show the efficient ridge preservation technique.

Materials and Methods:

Twenty patients were selected for this study. It was divided into the flap and flapless groups. In group A, the flap was elevated, tooth extraction was undertaken, the socket was cleaned, a graft was placed, a barrier was placed, and a suture was placed. In group B all the procedures were the same but without flap elevation. After surgery, clinical and radiographical parameters were recorded.

Result:

Flapless technique showed a better result in bone preservation. There was a low vertical bone loss in the flapless technique.

Conclusion:

Both techniques showed bone loss. But the flapless technique gave better results.

INTRODUCTION

Alveolar ridge preservation (APR) is the technique to preserve the alveolar ridge post-extraction so that alveolar bone can be adequately preserved for the placement of implants. Various studies have shown horizontal bone loss post-extraction.[1,2] It is always considered that elevation of the mucoperiosteal flap often leads to the loss of crestal bone.[3] It is usually considered that the elevation of mucoperiosteal leads to a decrease in blood supply to the healthy alveolar bone and hence leads to bone resorption.[4] The composition of crestal bone is very thin in characteristics.[5] Hence, the blood capillaries are very delicate, making them prone to resorption on the slightest disruption in the blood supply. These factors often encourage clinicians to avoid the reflection of the flap.

However, various studies have reported a minimal difference in bone loss between the flap and flapless surgery.[6] Apart from human studies, few animal studies have shown similar results.[7] Various studies have also shown crestal bone loss post-flap elevation.[8,9] Hence it becomes important to determine whether the crestal and alveolar bone loss is significant among flap and flapless procedures.

Hence the goal of the study was to evaluate the amount of bone loss in the flap and flapless techniques. The hypothesis of the study is that by doing the flapless technique, we will be able to preserve the blood supply to the bone, thus preventing bone loss.

MATERIALS AND METHODS

This was a randomized, double-blinded study conducted at the outpatient department of Karnavati School of Dentistry. All the ethical approvals were taken by the review board of Karnavati University (KU/KSD/IRB/2022/013) and were carried out according to the declaration of Helsinki version 2013.

Twelve males and eight females were included in the study. Adult patients who required single tooth extraction with a view to future implant placement, free from any systemic diseases, and given written consent were included in the study. Subjects who were diabetic, allergic to any graft or medication, had undergone any radiation therapy, and/or were taking medication were excluded from the study. All the subjects were divided into two groups. Group A consisted of a flap procedure whereas Group B consisted of a flapless procedure. Patients were randomized by the coin toss method.

Surgical technique

In the flap group, a full periosteal flap was elevated to expose the alveolar ridge. The flap was reflected beyond the mucogingival junction. While elevation it was made sure that the flap reflection was done at least 6 mm beyond the alveolar ridge. The teeth were extracted neatly with help of peristomes, elevators, and forceps. The extraction socket was then curetted and irrigated with betadine solution. DFDBA (Tata Memorial, Mumbai, India) was mixed in blood and placed in the extraction socket to the level of the crest and then the calcium sulfate barrier was placed. A high-density suture was placed to prevent the dislodgement of the graft along with the barrier membrane. In the flapless group, all the procedures were kept the same except for the elevation of the flap.

Each patient received oral hygiene instructions, a post-surgical dose of antibiotics (Amoxicillin 500 mg thrice daily for 3 days), and analgesics (ketorolac tromethamine 10 mg twice daily for 3 days). Patients have also prescribed 0.12% chlorohexidine gluconate mouthwash daily. Patients were recalled after 6 months for the recording of all the clinical parameters. Clinical parameters included Plaque Index, Gingival Index, Bleeding on Probing index, and all the hard tissue recording. Hard tissue recording includes 1. Horizontal ridge recoding at the crest. 2. Horizontal ridge recording at 5 mm below the crest. 3. Vertical height in relation to the distal or mesial border of the adjacent tooth. All the measurements were recorded by CT Scan.

Data analysis

All the data were analyzed by using SPSS (v21 for windows, NY, USA) software. Data were analyzed by using paired t-test. In all the tests, the significance P value was set to 0.05.

RESULTS

Twelve males and eight females of age group 28 to 42 were included in the study. Patients were randomly divided into two groups by coin toss method. Inter-group comparison of plaque and gingival index showed no difference at any stage of the study [Table 1].

Table 1.

Indices measurement for both groups

	Groups	Baseline	P	6 Months	P
Plaque Index	Flap	0.70±0.11	0.67*	0.44±0.27	0.78*
	Flapless	0.67±0.17		0.40±0.35
Gingival Index	Flap	1.48±0.21	0.55*	0.51±0.33	0.87*
	Flapless	1.52±0.33		0.49±0.22

*Non Significant

The crestal bone of group A at the baseline was 7.6 ± 1.3 mm and 6.5 ± 1.4 mm after 6 months. The bone loss from baseline to six months was statistically significant [P value 0.01, Table 2]. The crestal bone of group B at the baseline was 7.8 ± 1.7 mm and 7.1 ± 1.2 mm after 6 months. The bone loss from baseline to six months was statistically significant [P value 0.01, Table 2]. The crestal bone of group A at 6 mm from crest was 8.8 ± 1.2 mm and 8.3 ± 1.4 mm after 6 months. The bone loss from baseline to six months was not significant [P value 0.23, Table 2]. The crestal bone of group B at 6 mm from crest was 8.9 ± 1.4 mm and 9.1 ± 1.6 mm after 6 months. The bone loss from baseline to six months was not significant [P value 0.54, Table 2].

Table 2.

Intra-group comparison of the horizontal ridge at the crest and at 6 mm, for the flap and flapless (in mm)

	Position	Flap group	P	Flapless group	P
At crest	Baseline	7.6±1.3	0.01**	7.8±1.7	0.01**
	6 Month	6.5±1.4		7.1±1.2
At 6 mm from crest	Baseline	8.8±1.2	0.23*	8.9±1.4	0.54*
	6 Month	8.3±1.4		9.1±1.6

*Non Significant. **Significant

Intergroup comparison of all parameters was insignificant except crestal ridge comparison at 6 months time intervals [Table 3].

Table 3.

Intergroup comparison of the horizontal ridge at the crest and at 6 mm, for the flap and flapless (in mm)

Position	Groups	n	Baseline	P	6 months	P
At crest	Flap	10	7.6±1.3	0.23*	6.5±1.4	0.01**
	Flapless		7.8±1.7		7.1±1.2
At 6 mm from crest	Flap	10	8.8±1.2	0.38*	8.3±1.4	0.41*
	Flapless		8.9±1.4		9.1±1.6

*Non Significant. **Significant

After six months, group A showed a significant loss of bone height of 1.1 mm on the mesial side, whereas 1.2 mm on the distal side. On the other hand, group B showed significantly less bone loss of 0.6 mm on the mesial side and the same loss on the distal side [Table 4].

Table 4.

Vertical bone loss in both groups after six months

	Flap mean change	Flapless mean change
Mesial	−1.1±0.4	−0.6±0.7
Distal	−1.2±0.5	−0.6±0.6

DISCUSSION

The basis of this study is related to the reflection of the flap. It was a six-month ARP study undertaken from Jan 2022 to Dec 2022. This study was carried out among 20 patients with definitive exclusion and inclusion criteria with the help of a computer tomographic scanner. Although there are several studies comparing socket preservation among flapless and flap techniques,[10,11] there are only a few studies related to ridge preservation.[12] Although the DFDBA grafts treated both surgical sites, there was still a mild bone loss difference in both groups. This finding was in agreement with the study done by Mauricio G Araújo[13] Dariusz Filipek[14] in their study, stated that the bone loss was more in the flap group, but the loss was insignificant. The result of this study was very similar to ours.

Mohammed Jasim AL-Juboori[15] showed that the partial thickness flap reduced bone loss. In our study, too, flapless gave a little better results than the flap technique. This can be attributed to the abundant blood supply to the vital bone that the flapless technique provided. The flap group showed an increased loss of bone height compared to the flap group. This, again, can be attributed to the increased blood supply. Similar to our work, a study was done by Trever L Siu[16] showed a more significant bone loss in the flap technique.

Raising the flap may seem to be the predominant factor for bone loss, but we know that various factors may cause bone loss. The most common among them are facial bone thickness and tooth angulation. Regarding the technique of the surgery, it is yet to be decided which of the technique is better for preventing bone loss, but the flapless technique has some advantages over the flap technique.

CONCLUSION

Less crestal and vertical bone loss can be possible in the flapless technique when compared to the flap technique.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.