Single implant placement in the esthetic zone of non-preserved versus preserved alveolar ridges

15408 ORAL COMMUNICATION CLINICAL RESEARCH – SURGERY

Background

Local augmentation of a deficient buccal bone wall was demonstrated to effectively increase the soft tissue contour. Therefore, augmentation of the extraction socket was suggested to limit dimensional changes of the buccal bone wall. Additionally, connective tissue grafting of the buccal peri-implant soft tissue has been presumed to increase the soft tissue volume and to limit recession. Sealing the socket with connective tissue may potentially be even more beneficial for volume preservation.

Aim/Hypothesis

To assess the effect of single implant placement in preserved alveolar ridges (PAR) compared to non-preserved alveolar ridges accompanied with connective tissue grafting at implant placement (non-PAR) on the change in mid-buccal mucosal level (MBML), marginal bone level (MBL) and esthetics.

Material and Methods

In 20 patients with a single failing tooth, the extraction socket was augmented with anorganic and autologous bone because of a buccal bone wall defect >5 mm and sealed with a tuberosity mucosa graft. Four months later, all patients received a single implant in a preserved alveolar ridge (PAR). The PAR patients were compared with 20 patients with an already missing single tooth. The extraction socket had healed unassisted for at least 3 months (non-PAR) before the implant was placed. In both PAR and non-PAR patients, the buccal bone wall thickness was, when needed, augmented to achieve ≥2 mm with anorganic and autologous bone. Non-PAR patients additionally received a connective tissue graft from the palate in a buccal flap. Changes in MBML were assessed from intra-oral pictures and MBL changes from intra-oral radiographs after final crown placement (one month (T1), twelve (T12) months). The esthetics were determined by the Pink Esthetic Score-White Esthetic Score (PES WES) at T12.

Results

The study population consisted of 7 men and 13 women in the PAR group and 4 men and 16 women in the non-PAR group. There were no postoperative complications. All patients were available for analysis. Mean age was 42.0 ± 15.7 years and 35.1 ± 16.2 years in PAR and non-PAR patients, respectively. At T12, mean change in MBML was −0.15 ± 0.23 mm and 0.07 ± 0.29 mm (P = 0.01) for PAR and non-PAR patients, respectively. Changes in MBL in PAR patients were 0.03 ± 0.4 mm mesially and 0.13 ± 0.5 mm distally between T1 and T12. Changes in MBL in non-PAR patients were 0.06 ± 0.5 mm mesially and −0.01 ± 0.4 mm distally. No significant changes were observed for MBL (P = 0.55 for mesial implant side; P = 0.62 for distal implant side) as well as that esthetics were comparable between the groups. The need for a buccal augmentation at implant placement to achieve a ≥2 mm buccal bone wall thickness was significantly different between the groups, since the buccal bone wall had to be augmented in 9 PAR and 18 non-PAR patients.

Conclusion and clinical implications

Rehabilitation of a single failing tooth with a single implant placed in a preserved alveolar rigde or a non-preserved alveolar ridge accompanied with CTG results in non-relevant clinical changes in MBML and good esthetic and clinical outcomes. An alveolar ridge preserving augmentation procedure at the time of extraction of a failing tooth is preferred when aiming for a reduction of treatment time.