Effect of amount of biomaterial used for maxillary sinus lift on volume maintenance of grafts

Radiological Study on the Evolution of the Biomaterial's Image (Shape, Density, Vertical Dimensions) after the Lateral Sinus Lift

The aim of this study is to evaluate the long-term changes of sinus lift material. Materials and methods: We included a total number of 35 patients (20 men and 15 women), between 32 and 80 years old, evaluated on a timeframe of up to 11.6 years. Diverse biomaterials were used (allograft, xenograft, alloplastic, combinations of them), with autologous bone in some cases. Results: The appearance of the top plane of the bone over time took a large dome shape (36% of cases), a linear shape (32% of cases), an irregular shape (23% of cases), or had micro domes above the implants (7%). No significant differences were found between the groups regarding age. The radiological density of the biomaterial tended to equalize that of the native bone. The final vertical dimensions seemed to be independent of the initial native bone height but seemed to be correlated with the amount of applied biomaterial. For the study group, the biomaterial contracted on average by 10% for the maximum height (H max) and 20% for the minimum height (H min), which can explain the tendency of the upper border of the biomaterial to curve. The annual H max contraction ranged from -0.09 to +0.18 with a mean value of 2.67% (SD = 0.04, CI: [0.011, 0.041]). The median value was 1.8%. The annual H min contraction ranged from -0.24 to +0.24, with a mean value of 4.33% (SD = 0.07, CI: [0.021, 0.065]). The median value was 3.59%. There were no statistically significant gender differences (Mann-Whitney U, p = 0.483, p = 0.642). The additional application of biomaterial together with the implants seemed to have a beneficial effect on the final vertical dimension of the bio-transformed material.

Application Effect of External and Internal Elevation of Maxillary Sinus in Implant Restoration of Posterior Maxilla

Objective

To explore and analyze the application effect of external and internal elevation of the maxillary sinus in implant restoration of the posterior maxilla.

Methods

A total of 84 patients undergoing implant restoration of the posterior maxilla in the hospital were enrolled between January 2019 and March 2021. According to the random number table method, they were divided into the observation group (n = 42) and the control group (n = 42). The control group underwent external elevation of the maxillary sinus, while the observation group underwent internal elevation of the maxillary sinus. At 6 h, 12 h, and 24 h after surgery, the pain degree between the two groups was compared. All were followed up at 6 months after surgery. The osseointegration (bone resorption around implants, elevation height of maxillary sinus floor, average healing time) and soft tissues (bleeding index, plaque index, probing depth) in both groups were observed. The occurrence of postoperative complications was recorded.

Results

At 6 h, 12 h, and 24 h after surgery, VAS scores in the observation group were significantly lower than those in the control group (P < 0.05). At 6 months after surgery, bone resorption and elevation height of the maxillary sinus floor in the observation group were significantly higher than those i.0.0n the control group, and the average healing time was significantly shorter than that in the control group (P < 0.05). The bleeding index, plaque index, and probing depth in the observation group were significantly lower than those in the control group (P < 0.05). There was no significant difference in the incidence of postoperative complications between the observation group and the control group (9.52% vs. 19.05%) (P > 0.05).

Conclusion

The application effect of internal elevation of the maxillary sinus is good in implant restoration of the posterior maxilla, which can relieve pain and swelling and improve implant effect.

Histomorphometric Evaluation of Bone-Guided Regeneration in Maxillary Sinus Floor Augmentation Using Nano-Hydroxyapatite/Beta-Tricalcium Phosphate Composite Biomaterial: A Case Report

Background

The development of techniques in biomaterials design and production added to advanced surgical procedures which enabled better and more predictable clinical outcomes. Maxillary sinus floor augmentation (MSFA) is among the more studied bone-guided regeneration procedure in the literature. The MSFA could be considered the gold standard procedure for bone-guided regeneration as it provides suitable functional and aesthetic solutions to alveolar ridge atrophy due to tooth loss.

Purpose

This study aimed to conduct a detailed histomorphometric evaluation of collagen production in SFAs bone-guided regeneration, using nano-hydroxyapatite/ß-tricalcium phosphate (nano-HA/ß-TCP) composite.

Patients and Methods

A 52-year-old female had the left upper second premolar condemned due to periodontal disease, then a tooth implant replacement was planned. Due to maxillary sinus pneumatization, the MSFA had to be done before implant placement. Nano-HA/ß-TCP composite (2g) was used in the MSFA procedure. After nine months of the healing process, during the Cone Morse implant installation process, bone samples were collected for histologic analysis (sirius red, hematoxylin/eosin, polarized microscopy). Six months after implant installation, a ceramic crown was installed according to the patient’s request.

Results

Proper masticatory function and aesthetics were re-established. The histomorphometric evaluation indicated that nano-HA/ß-TCP composite did not show any area devoid of cellular activity in sirius red or hematoxylin/eosin staining and the percentage (%) of new bone collagen fibers was achieved using polarization technique evaluation.

Conclusion

According to these results, nano-HA/ß-TCP composite presented clinical and histomorphometric properties suit to be used as bone-guided regeneration biomaterial in MSFA. Furthermore, nano-HA/β-TCP composite provided a favorable nano-environment to bone cells, enhancing bone matrix production.