Maxillary Sinus Floor Augmentation With Autogenous Bone Graft From the Ascending Mandibular Ramus

Maxillary sinus floor augmentation using sponge- and cotton-like graft materials in a rabbit model

OBJECTIVES

Bone graft materials commonly used for maxillary sinus floor augmentation (MSFA), including hydroxyapatite (HAp) and β-tricalcium phosphate (β-TCP), are mostly granular and have poor handleability. HAp/collagen composite material (HAp/Col) and β-tricalcium phosphate (β-TCP)/poly(L-lactide-co-glycolide) (PLGA) have shown promise but their application in MSFA as bone graft materials remains unclear. Here, we investigated the bone-forming behavior of HAp/Col and β-TCP/PLGA in an MSFA rabbit model.

METHODS

Male Japanese white rabbits were used. HAP/Col or β-TCP/PLGA was randomly applied to the MSFA model. The specimens were harvested at 4 weeks (W), 8W, 16W, and 24W after surgery, and the augmented regions were evaluated using micro-computed tomography and histological analyses.

RESULTS

The graft materials were retained up to 16W in the HAp/Col group and 24W in the β-TCP/PLGA group. The augmented volume detected in the HAp/Col group at 4W was substantially reduced at subsequent time points. However, in the β-TCP/PLGA group, the volume observed at 4W was maintained up to 24W. In the HAp/Col group, the bone mineral content (BMC) at 4W was significantly lower than that at 8W (p = 0.03716), and this elevated BMC was significantly decreased at 16W (p = 0.00185) and 24W (p = 0.00236). In the β-TCP/PLGA group, the BMC tended to increase from 4W to 16W and then decreased.

CONCLUSIONS

Both HAp/Col and β-TCP/PLGA are useful for MSFA because of their ability to form new bone and good handleability. The appropriate graft material should be selected depending on the application needs while understanding the properties of the newly formed bone.

APCs in sinus floor augmentation

After tooth loss in the posterior area of the maxilla, sinus floor elevation is often required to compensate the vertical bone loss due to sinus pneumatization. This narrative review reports on the potential benefits of autologous platelet concentrates (APCs) during this procedure. As for transcrestal approach, APCs have been used as "sole" substitute/graft. However, because of the low number of clinical trials available with PRGF, and even none for PRP, no definitive conclusions can be made regarding their efficacy. The number of studies on the use of L-PRF were outnumbered indicating good feasibility for vertical bone gain, with a high implant survival rate and a low degree of complications. PRP and PRGF have not been studied as a "single/sole" substitute for a one-stage lateral window approach, probably because of the weak physical characteristics of the membranes. L-PRF alone appears to be a predictable grafting material for lateral maxillary sinus grafting and a reduced RBH should not be considered as a risk factor. Compared to a "standard" bone substitute L-PRF shows slightly less vertical bone gain (consider enough membrane application and use of bony window as new sinus floor roof over the implant apices), enhanced early resorption (first 6 months after application), but a similar stable bone gain afterward. For a two-stage lateral window approach, APCs "alone" cannot be recommended, due to their weak withstand to the sinus pneumatization forces. APCs combined with bone substitutes seem to accelerate bone formation, without any additional benefits on the long-term new bone gain. The use of L-PRF membranes for the treatment of perforations appears to be an effective treatment option, but further clinical studies are needed to confirm this. Even though the abovementioned statements are based on large numbers of studies, additional RCTs comparing APCs with different types of grafting procedures for sinus elevation are needed.

Maxillary sinus floor augmentation with autogenous bone graft compared with composite grafts: A one-year single-blinded randomized controlled trial

OBJECTIVE

The objective was to assess the one year implant treatment outcome and patient-related outcome measures (PROMs) following maxillary sinus floor augmentation (MSFA) with autogenous bone graft (ABG) from the zygomatic buttress (control) compared with 1:1 mixture of ABG and anorganic porcine bone mineral (APBM) (Test I) or biphasic bone graft material (BBGM) (Test II).

MATERIALS AND METHODS

Sixty healthy patients (34 females, 26 males) were randomly allocated to either control or test groups. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of peri-implant tissue, peri-implant marginal bone loss, frequency of complications, and PROMs using Oral Health Impact Profile-14 combined with questionnaire assessing patient perception of peri-implant soft tissue, prosthetic solution, implant function, and implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was .05.

RESULTS

All suprastructures and implants were well-functioning after one year of functional implant loading. There was no significant difference between control and test groups in any of the applied outcome measures. The implant stability significantly increased from implant placement to abutment connection within all groups (p < .001). High patient satisfaction and significant improvement in oral health-related quality of life was also reported within all groups.

CONCLUSION

This study demonstrates that MSFA with composite grafts containing minimal amounts of ABG reveals comparable implant treatment outcomes as compared with ABG alone, after one year of functional implant loading. Extensive ABG harvesting in conjunction with MSFA therefore seems not to be needed.

The peri-implant mucosa color: A systematic appraisal of methods for its assessment and clinical significance

BACKGROUND

Peri-implant mucosa color (PMC) seems to be one of the main parameters affecting the esthetic outcome of implant therapy. However, more emphasis should be given to its assessment and reporting.

PURPOSE

To describe the available evidence on methods to assess and report the color of the peri-implant mucosa (PMC) and the respective clinical relevance.

MATERIAL AND METHODS

A comprehensive electronic and manual search was performed to identify clinical studies reporting on PMC.

RESULTS

A total of 121 studies were included. PMC was evaluated at the time of the follow-up visit (chairside) in 45.5% studies. PMC assessment was performed qualitatively, by comparing PMC with adjacent and/or contralateral gingiva (78.6%) or quantitatively, using spectrophotometry (20.7%) or a software on clinical photographs (0.8%). The most performed method to assess PMC was through esthetic indices (76.9%), either at the time of the follow-up visit (chairside) or at later time point using photographs. Quantitative reporting of PMC included averages of points from esthetic indices or color differences to natural gingiva expressed with the CIELAB color system. PMC assessment allowed describing color discrepancies compared to natural gingiva, evaluating color changes over time, and comparing the outcomes of different treatment modalities. PMC assessment through spectrophotometry was additionally utilized to assess the role of mucosal thickness (MT) on PMC.

CONCLUSIONS

Various methods for PMC assessment and reporting were described, including visual assessment, mainly through esthetic indices, and spectrophotometry. PMC evaluation has allowed to demonstrate the factors affecting the color of the peri-implant soft tissue, such as the type of abutment/restoration, MT, and soft tissue augmentation.

Patient's perception of recovery after sinus membrane elevation and blood coagulum compared with 1:1 mixture of autogenous bone graft and deproteinized porcine bone mineral. Secondary outcomes from a single-blinded randomized controlled trial

OBJECTIVE

The objective was to assess patient's perception of recovery after maxillary sinus membrane elevation (MSME) and blood coagulum (test) compared with maxillary sinus floor augmentation (MSFA) and 1:1 mixture of autogenous bone graft from the buccal antrostomy and deproteinized porcine bone mineral (DPBM) (control).

MATERIALS AND METHODS

Forty healthy patients were randomly allocated to test or control. Oral health-related quality of life (OHRQoL) was evaluated by Oral Health Impact Profile-14 (OHIP-14) at enrollment and 1 week postsurgical. Recovery was estimated by questionnaires and visual analog scale assessing pain, social and working isolation, physical appearance, eating and speaking ability, diet variations, sleep impairment, and discomfort after 1 week and 1 month. Mean differences were expressed with 95% confidence interval (CI). Association between OHRQoL and recovery was estimated. p-value below .05 was considered statistically significant.

RESULTS

Maxillary sinus membrane elevation revealed 2.1 less days of pain (p = .03, 95% CI: 0.2-4.1) and 1.2 days of sick leave (p = .01, 95% CI: 0.3-2.1) compared with MSFA. No significant difference was observed in eating and speaking ability, physical appearance, work performance, and sleep impairment. No significant association between impaired OHRQoL and recovery was observed. Females reported 4.77 higher OHIP-14 score compared with males (p = .01, 95% CI: 1.60-7.94), while association between age and OHIP-14 was -0.10 (p = .28, 95% CI: -0.28 to 0.08).

CONCLUSION

Maxillary sinus membrane elevation revealed significantly less days of pain and sick leave compared with MSFA. Harvesting of autogenous bone graft seems, therefore, to have a significant impact on perception of recovery.

Single-crown restorations supported by short implants (6 mm) compared with standard-length implants (13 mm) in conjunction with maxillary sinus floor augmentation: a randomized, controlled clinical trial

BACKGROUND

The purpose of the present study was to test the H0-hypothesis of no difference in the clinical and radiographical treatment outcome of single-crown restorations supported by short implants compared with standard length implants in conjunction with maxillary sinus floor augmentation (MSFA) after 1 year of functional implant loading. Forty patients with partial edentulism in the posterior part of the maxilla were randomly allocated to treatment involving single-crown restorations supported by short implants or standard length implants in conjunction with MSFA. Clinical and radiographical evaluation were used to assess survival of suprastructures and implants, peri-implant marginal bone loss (PIMBL), biological, and mechanical complications.

RESULTS

Both treatment modalities were characterized by 100% survival of suprastructures and implants after 1 year. Mean PIMBL was 0.60 mm with short implants compared with 0.51 mm with standard length implants after 1 year of functional loading. There were no statistically significant differences in survival of suprastructure and implants, PIMBL, and mechanical complications between the two treatment modalities. However, a higher incidence of biological complications was associated with standard length implants in conjunction with MSFA.

CONCLUSION

Within the limitations of the present study, it can be concluded that single-crown restorations supported by short implants seems to be comparable with standard length implants in conjunction with MSFA. However, long-term studies are needed before final conclusions can be provided about the two treatment modalities.

TRIAL REGISTRATION

Clinicaltrials.Gov ID: NCT04518020 . Date of registration: August 14, 2020, retrospectively registered.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Alone Compared with Alternate Grafting Materials: a Systematic Review and Meta-Analysis Focusing on Histomorphometric Outcome

Objectives

The objective of present systematic review was to test the hypothesis of no difference in histomorphometric outcome after maxillary sinus floor augmentation with autogenous bone graft alone compared with alternate grafting materials applying the lateral window technique.

Material and Methods

MEDLINE (PubMed), Embase and Cochrane library search in combination with hand-search of relevant journals were conducted. Human studies published in English until the 25^th of March, 2020 were included. Histomorphometric outcomes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval (CI).

Results

Electronic search and hand-searching resulted in 1902 entries. Sixteen randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. Descriptive statistics showed comparable or improved histomorphometric outcomes with autogenous bone graft. Meta-analysis revealed a mean difference of -7.1% (CI = -11.0 to -3.2) indicating a significant higher amount of bone after maxillary sinus floor augmentation with autogenous bone graft compared with alternate grafting materials. Subgroup analysis demonstrated a non-significantly differences of -3.7% (CI = -10.9 to 3.4), -11.5% (CI = -25.9 to 2.8), 2.2% (CI = -16.9 to 21.3), and -4.6% (CI = -14.4 to 5.2), when autogenous bone graft was compared with allogeneic bone graft, xenograft, composite grafting materials involving xenograft or synthetic biomaterial mixed with autogenous bone graft, respectively.

Conclusions

Maxillary sinus floor augmentation with autogenous bone graft seems to facilitate improved histomorphometric outcomes compared with alternate grafting materials. However, the included studies were characterised by an unclear risk of bias and various methodological confounding factors. Hence, the conclusions drawn from the results of present study should be interpreted with caution.