Background: Dental implants have become the standard for replacing missing teeth. However, patients’ demands for shorter treatment times and the desire for aesthetics in their results can complicate the rehabilitation process, particularly when poor-quality bone is involved. In order to address these challenges, new methods of treating implant surfaces have been introduced. These methods aim to make the implants superhydrophilic and bioactive, enhancing their functionality and interactions with the surrounding tissues. Aim: The aim of the study was to retrospectively examine the efficacy of a superhydrophilic and bioactive implant for treatment of the edentulous maxillary anterior area. The study also aimed to evaluate whether this improved implant surface, by enhancing the osseointegration processes, could serve as a factor in speeding up the loading protocols. Materials and Methods: For this retrospective study, a total of 13 implants were included: 6 delayed restored implants and 7 immediately loaded implants placed in the anterior maxillary area. Clinical, radiographic, and esthetic outcomes were assessed. Baseline measurements of the insertion torque value (ITV) and stability implant quotient (ISQ) were recorded for all implants. In the early-loaded group, these measurements were also taken 30 days (t30) and 45 days (t45) after the placement of the implant to monitor their changes over time. Marginal bone loss (MBL) was calculated according to the changes in marginal bone level on intraoral X-rays taken at two different time points: at baseline and one year after loading. To evaluate the esthetic results, the pink esthetic score (PES) and the white esthetic score (WES) were assessed. For this evaluation, intraoral photographs were taken one year after implant loading. Results: A total of 7 implants were immediately restored, with a mean ITV of 32.29 ± 9.01 Ncm and a mean ISQ of 72.71 ± 2.81. These implants were placed in a bone environment with a mean density of 410.00 ± 194.42 HU. On the other hand, 6 implants with delayed loading had a mean ITV of 28.50 ± 3.27 Ncm, an ISQ of 67.92 ± 8.43, and a mean bone density of 607.50 ± 140.83 HU. The mean PES and WES after 1 year were, respectively, 8.71 ± 1.89 and 8.57 ± 0.79 for immediate and 8.33 ± 1.36 and 9.17 ± 1.33 for delayed-loaded implants. At 12 months after loading, the immediately loaded group had a MBL of 0.29 ± 0.29 mm, while the delayed-loaded group had a MBL of 0.33 ± 0.25. No statistically significant differences between the two treatment groups were found for any of the evaluated outcomes. Conclusions: Despite the limitations of this study, the obtained results may support the use of a superhydrophilic and bioactive implant surface for implant-prosthetic rehabilitation in critical loading protocols with satisfactory esthetic results.
Background: Due to the lack of data on bone-to-graft contact (BGC) over time in the various regions within the subantral space of the augmented sinus floor, the present study aimed to evaluate the osteoconductivity of deproteinized bovine bone mineral (DBBM) with granules of different sizes applied in maxillary sinus floor elevation. Methods: A maxillary sinus augmentation was performed bilaterally in 18 rabbits using DBBM with particle dimensions of either 0.125–1.0 mm or 1–2 mm. The antrostomy was covered using a collagen barrier. The animals were euthanized in groups of six after 2, 4, and 8 weeks of healing. MicroCT and histological analyses were performed. Results: After 2 weeks of healing, BGC was 10.9% and 11.9% for the small and large granule sites, respectively. After 8 weeks of healing, the BGC increased to 65% and 62% at the small and large granule sites, respectively. The highest values were located close to the bony walls and the bony window. New bone content developed between 2 and 8 weeks from 7.0% to 27.6% and from 6.1% to 27.6% at the small and large granule sites, respectively. Conclusions: Similar outcomes in osteoconductivity and bone formation were found at both small and large DBBM granule sites.
Background: The treatment of the surface of titanium implants with argon plasma improved its hydrophilicity and cell adhesion, resulting in higher bone apposition on implant and graft surfaces. The spontaneous perforation over time of the sinus mucosa after sinus augmentation has been documented in experimental studies at both implants and graft particles. The aim of the present study was to evaluate the influence of plasma argon treatment of the implant surface on bone apposition and on the rate of sinus mucosa perforations. Methods: A sinus lifting procedure was performed bilaterally in sixteen rabbits, and implants, either treated with argon plasma or left without treatment (control), were placed simultaneously without grafts. After 8 weeks, histological analyses were carried out. Results: A collapse of the sinus mucosa was observed at all implants. Twenty-four out of thirty-two implants presented sinus mucosa perforations at the apex. Several perforations were also found at the threads. Thinned mucosa sites (width < 40 µm) were found around almost all implants. About 2.6–2.9 mm of the apical regions of the implant did not present signs of osseointegration and about 1.3 mm were exposed to the sinus cavity. No statistically significant differences were found between plasma and control sites. Conclusions: In conclusion, the sinus mucosa was damaged and perforated by direct contact with treated and non-treated implant surfaces. The treatment of the implant surface with argon plasma did not affect the outcomes.
1 November 2021 in Journal of Stomatology Oral and Maxillofacial Surgery
Background: Experimental studies have shown a progressive thinning and perforations of the sinus mucosa associated with sharpened edges and the cutting projections of graft particles used simultaneously for maxillary sinus augmentation. Hence, the aim of the present study was to evaluate the damaging effects of two different bovine grafts on the sinus mucosa after sinus augmentation. Methods: Twenty New Zealand rabbits received a bilateral sinus lifting using, as fillers, two different types of deproteinized bovine bone in granules, one processed at low temperature (low-T group), and the other at high temperature (high-T group). Thinned mucosa sites (<40 µm) and perforations were evaluated in the sinus mucosa that were in contact with graft granules after 2 and 10 weeks, in ten animals per period. Results: After 2 weeks of healing, the number of thinned mucosa sites was 118 in the low-T group, and 149 in the high-T group (p = 0.191). At the 10-week assessment, the thinned sites increased to 237 and 195 sites, respectively. The numbers of sinus mucosa perforations after 2 weeks were eight and three in the low-T and high-T group, respectively. At the 10-week evaluation, the perforations increased to 19 in the low-T group, and to 14 in the high-T group. Conclusions: The contact with bovine xenografts yielded thinning and perforations of the sinus mucosa. Despite the differences in characteristics and dimensions, no differences were found between the two xenografts in the numbers of thinning mucosa sites and perforations. However, a trend of more events was found in the low-T compared to the high-T group.
Background: The Schneiderian membrane (SM) that is in contact with biomaterial granules may become thinner and eventually perforate. It has been shown that these events are related to the biomaterial used. Hence, the main aim of the present study was to compare the damaging effects of two xenografts with different resorbability rates on SM. The secondary aim was to evaluate the possible protection from damage offered by a collagen membrane placed adjacent to the SM and by inward displacement of the bone window with the SM during elevation. Methods: Thirty-six albino New Zealand rabbits underwent bilateral sinus elevation. One group of 18 animals received deproteinized bovine bone mineral (DBBM group) and the other received swine-collagenated corticocancellous bone (collagenated group). Moreover, in the DBBM group, the bone window was displaced inward during elevation in one sinus together with the SM. In the collagenated group, a collagen membrane was placed adjacent to the SM in one sinus. Six animals were assessed per period after 2, 4, and 8 weeks. Results: The mean pristine mucosa width ranged between 67 µm and 113 µm, and none had a width of <40 µm. In the 2-week group, the elevated mucosa of the DBBM group presented 59 thinned sites and five perforations, while in the collagenated group, 14 thinned sites and one perforation were observed. Damage to SM decreased in number in the 4-week treatment group. In the 8-week group, the number of thinned sites in the DBBM group increased to 124, and the perforations to 8. In the collagenated group, 7 thinned sites and 1 small perforation were observed. Conclusions: More damage to the Schneiderian membrane was observed in the DBBM group than in the collagenated group. The presence of the inward bone window offered protection from damage to the Schneiderian membrane.