Histomorphometric analysis of maxillary sinus augmentation with calcium phosphate nanocrystal-coated xenograft

The bone lid technique in lateral sinus lift: a systematic review and meta-analysis

Objective

This systematic review aimed at assessing the effect of the repositioned bone lid on bone augmentation in lateral sinus lift in pre-clinical in vivo and clinical studies. Secondary aims were to report on the healing of the bone window and to assess the implant survival rate.

Material and methods

Animal and human studies comparing lateral maxillary sinus floor elevation in combination or not with the repositioned bone lid were retrieved from MEDLINE (PubMed), Web of Science and Cochrane online library. Studies published in English up to April 2022 and reporting on histological and/or radiographic outcomes were considered. Case reports, case series and reviews were excluded. A hand search was also conducted. Risk of bias was assessed and meta-analysis performed to investigate the effect of the bone lid on new bone formation.

Results

After screening, 5 animal studies (4 in rabbits, 1 in sheep) and 2 clinical studies (1 RCT, 1 case–control) were included. Meta-analysis confirmed a higher new bone formation in rabbits at 2 and 8 weeks using the bone lid. The two clinical studies investigated lateral sinus lift with concomitant implant placement and reported similar results and high short-term implant success rate in both test and control groups.

Conclusions

The meta-analysis provided moderate evidence that the repositioned bone lid favored the formation of new bone to a higher extent as compared to resorbable membranes in animal studies. Implant success seems not to be influenced by the technique in the short term.

Histological evaluation of two different anorganic bovine bone matrixes in lateral wall sinus elevation procedure: A retrospective study

Introduction:

Grafting in oral implantology involves bone augmentation procedures with various bone graft materials. Success of such procedures is evaluated through the amount of bone volume and bone formed at the grafted site. The primary aim of this prospective study was to histomorphometrically evaluate and compare the new bone formation with Bio Oss or Cerabone in the lateral approach sinus augmentation procedure.

Materials and Methods:

The research targeted 22 patients who were either partially or completely edentulous posterior maxilla with residual alveolar height 3 mm at the site of implantation and underwent a two staged surgical protocol, with a lateral approach sinus grafting with either Bio Oss or Cerabone. Bone trephine biopsies for histological analysis were harvested 6 months after augmentation while preparing the osteotomies for implant placement trephine. The histologic evaluation was performed comparing the newly formed bone, marrow spaces, biomaterial particles remnants, and presence of osteocytes embedded in both trabecular bone and bone tissue near the anorganic bovine bone.

Results:

The present study showed that neither of the graft material showed any active osteoclasts and host inflammatory reaction. From sites grafted with Cerabone, an ample amount of mature lamellated bone formation was seen, also host inflammatory response was indicative of minimal reactive inflammatory response suggestive of good acceptability of the graft material by the host. No significant differences between the groups could be detected with regard to new bone formation and residual bone substitute.

Conclusion:

The results of the study illustrates that both the bone substitute materials allow predictable new bone formation in sinus augmentation procedures.

Membrane perforation rate in lateral maxillary sinus floor augmentation using conventional rotating instruments and piezoelectric device-a meta-analysis

Objectives

Maxillary sinus augmentation (MSA) is a successful and predictable intervention with low complication rates. Perforations of the Schneiderian membrane may occur impairing the general success. The aim of this study was to compare the incidence of membrane perforations between conventional rotating instruments and piezoelectric devices in a meta-analysis.

Material and methods

An electronic research on MEDLINE and PubMed database was performed evaluating the literature from 1980 till 2016. Meta-analysis was performed with the studies matching the inclusion criteria. The incidence of perforations between conventional and piezo during the lateral maxillary sinus floor elevation was determined, and forest plots and a t test for significance analysis were performed.

Results

The search provided 377 articles of which 69 could be included. Selected non-randomised and non-controlled prospective and retrospective studies were incorporated. Conventional rotary instruments were associated with a perforation rate of 24%, the piezoelectric devices with 8% with statistically significant difference between both modalities (p < 0.05).

Conclusion

Membrane perforations in MSA may be significantly reduced applying piezoelectrical devices for MSA.

SEM-EDX Study of the Degradation Process of Two Xenograft Materials Used in Sinus Lift Procedures

Some studies have demonstrated that in vivo degradation processes are influenced by the material’s physico-chemical properties. The present study compares two hydroxyapatites manufactured on an industrial scale, deproteinized at low and high temperatures, and how physico-chemical properties can influence the mineral degradation process of material performance in bone biopsies retrieved six months after maxillary sinus augmentation. Residual biomaterial particles were examined by field scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) to determine the composition and degree of degradation of the bone graft substitute material. According to the EDX analysis, the Ca/P ratio significantly lowered in the residual biomaterial (1.08 ± 0.32) compared to the initial composition (2.22 ± 0.08) for the low-temperature sintered group, which also presented high porosity, low crystallinity, low density, a large surface area, poor stability, and a high resorption rate compared to the high-temperature sintered material. This demonstrates that variations in the physico-chemical properties of bone substitute material clearly influence the degradation process. Further studies are needed to determine whether the resorption of deproteinized bone particles proceeds slowly enough to allow sufficient time for bone maturation to occur.