Original title: Possible applications for a biodegradable magnesium membrane in alveolar ridge augmentation – retrospective case report with two years of follow-up
Palkovics D, Rider R, Rogge S, Kačarević Ž, Windisch P. Medicina. 2023; 59(10):1698. Published 2023 Sep 22. doi: 10.3390/medicina59101698
https://www.mdpi.com/2491342

This case report demonstrates the application of the NOVAMag® membrane for horizontal and horizonto-vertical alveolar ridge augmentations using two different surgical approaches. Short-term volumetric and linear hard tissue gain as well as long-term radiographic outcomes were evaluated.  

INITIAL SITUATION

Case #1: A 38-year-old patient lost her lower right central incisor (tooth 41) due to advanced periodontal bone loss. The neighboring tooth (tooth 31) presented a Miller Class III gingival recession. The defect was classified as a medium horizontal alveolar ridge defect according to the horizontal-vertical-combination (HVC) classification system; therefore, a staged horizontal alveolar ridge augmentation and implant placement were scheduled.

Case #2: A 56-year-old patient had an edentulous area in the position of teeth 45 and 46. The defect was classified as a medium combination defect and the patient was scheduled for staged alveolar ridge augmentation.

TREATMENT APPROACH

Case #1: Guided bone regeneration (GBR) was performed with a bilayer tunnel flap approach. NOVAMag® membrane was placed through remote vertical incisions and fixed subperiosteally with titanium pins. The space between the NOVAMag® membrane and the bone surface was filled with 1:1 mixture of autogenous chips and bovine xenogeneic granules (cerabone®). A collagen matrix (mucoderm®) was then placed underneath the mucosa to achieve an ideal soft tissue contour. Implant placement was planned six months post-augmentation.

Case #2: Guided bone regeneration (GBR) was performed with a conventional split-thickness flap design. NOVAMag® membrane was fixed with titanium pins on the lingual aspect, after which the defect area was filled with 1:1 mixture of autogenous chips and bovine xenogeneic granules (cerabone®). Subsequently, the NOVAMag® membrane was folded over the grafted area and secured on the buccal aspect of the defect with titanium pins. Implant placement was planned six months post-augmentation.

OUTCOME

Case #1: Radiographic three-dimensional evaluation of the defect site at baseline and 6 months after the augmentation showed a volumetric hard tissue gain of 0.12 cm³. Linear vertical hard tissue gain of 0.79 mm was measured from the deepest point of the defect. Hard tissue gains in the horizontal direction were measured as 0.93 mm, 1.23 mm, and 1.38 mm at 1, 2, and 3 mm-s apical to the top of the alveolar crest, respectively. The dehiscence at tooth 32 was reduced from 4.51 mm to 2.68 mm. Following a 6-month healing period, the implant was placed without any further augmentation. The final intraoral radiograph obtained two years after the delivery of the final restoration showed a stable situation with no marginal bone loss.

Case #2: Radiographic three-dimensional evaluation of the defect site at baseline and 6 months after the augmentation showed a volumetric hard tissue gain of 0.36 cm³. Linear vertical hard tissue gain of 2.77 mm was measured from the deepest point of the defect. Hard tissue gains in the horizontal direction were measured as 4.37 mm, 4.33 mm, and 3.37 mm at 1, 2, and 3 mm-s apical to the top of the alveolar crest, respectively. Following a 6-month healing period, two implants were placed without any further augmentation. The Intraoral radiograph obtained at the two-year follow-up showed a stable marginal bone level with no signs of peri-implant bone loss.

CONCLUSION

Excellent results were achieved with the resorbable metal NOVAMag® membrane in the reconstruction of a predominantly horizontal defect using a tunnel approach as well as in the reconstruction of a defect with a horizontal and vertical component using a split-thickness flap design. The versatility of the NOVAMag® membrane for GBR applications was demonstrated in this study. Over the follow-up period of two years, a stable peri-implant hard and soft tissue was established, and no marginal bone loss or signs of inflammatory processes were reported.
Due to its ability to maintain space for graft osteogenesis while being gradually resorbed by the human body, the NOVAMag® membrane overcomes the limitations of conventional collagen membranes.