TITLE (100 CHARACTERS):
A randomized clinical trial comparing 3 biomaterials for sinus augmentation: histologic outcomes.

AUTHORS
Giovanna Iezzi, Department of Oral, Medical and Biotechnological Sciences, University G. d’Annunzio of Chieti-Pescara, Italy. Address: via dei vestini 31, 66100 Chieti, Italy
Flavia Iaculli, Department of Oral, Medical and Biotechnological Sciences, University G. d’Annunzio of Chieti-Pescara, Italy. Address: via dei vestini 31, 66100 Chieti, Italy
Margherita Tumedei, Department of Oral, Medical and Biotechnological Sciences, University G. d’Annunzio of Chieti-Pescara, Italy. Address: via dei vestini 31, 66100 Chieti, Italy
Stefania Lepore, Department of Oral, Medical and Biotechnological Sciences, University G. d’Annunzio of Chieti-Pescara, Italy. Address: via dei vestini 31, 66100 Chieti, Italy
Alexandre Perez, Unit of oral Surgery and Implantology, University Hospital of Geneve, University of Geneve, Switzerland.  Address: rue Michel-Servet 1, 1211 Geneve 4, Switzerland
Nicola Alberto Valente, Unit of Oral Surgery and Implantology, University Hospital of Geneve, University of Geneve, Switzerland.  Address: rue Michel-Servet 1, 1211 Geneve 4, Switzerland
Antonio Barone, Unit of Oral Surgery and Implantology, University Hospital of Geneve, University of Geneve, Switzerland.  Address: rue Michel-Servet 1, 1211 Geneve 4, Switzerland

BACKGROUND (478 CHARACTERS):  
Crestal bone resorption after tooth extractions and pneumatization of the maxillary sinus could make challenging the implant-prosthetic rehabilitation of the posterior maxilla. The sinus floor augmentation is used in order to improve the height of residual crestal bone and to allow the implant placement in an adequate amount of bone. Several biomaterials have been used to perform this procedure without a clear indication on what biomaterial could be considered the best one.

AIM/HYPOTHESIS (300 CHARACTERS):  The aim of this randomized clinical trial was to evaluate and compare histopathological and histomorphometrical outcomes of 3 types of biomaterials, such as TCP/HA ratio 90/10%, TCP/HA ratio 90/10% plus hyaluronic acid and deproteinized bovine bone mineral (DBBM), used for maxillary sinus grafting. 

MATERIALS AND METHODS (1000 CHARACTERS): 
Twelve patients (ten females and five males, with a mean age of 51.73 ± 11.53) were enrolled in the study. The patients – each one received only one sinus lift included in the study- were randomly allocated in 3 groups: DBBM (control), TCP/HA (test1) and TCP/HA+hyaluronic acid (test2). The same surgical procedures were performed in all groups, and bone biopsies were harvested from the implant sites 9 months postoperatively for histological and histomorphometric evaluations as the primary outcome of the study. The secondary outcomes were post-surgical complication and radiological bone gain. The biopsies were fixed in 10% formalin and processed to obtain thin ground sections. The specimens were dehydrated and embedded in a glycolmethacrylate resin.  After polymerization the specimens were sectioned and stained with basic fuchsin and toluidine blue. Histomorphometric analysis was performed by evaluating the amount of newly formed bone, residual grafted material and marrow spaces.

RESULTS (1000 CHARACTERS)
Four patients for each group were treated and received dental implants. No complication was observed during sinus augmentation and at implant placement. The control group showed biomaterial particles connected by newly formed bone; at higher magnification, large osteocytic lacunae were observed close to the residual biomaterial particles. Histological and histomorphometrical analyses were very similar for the test1 and test2 groups: at low magnification both groups showed thin trabecular bone with large marrow spaces and a small amount of residual biomaterial; at higher magnification, residual biomaterial undergoing remodeling was observed. Many small blood vessels were observed in the marrow spaces. No groups showed any inflammatory infiltrate. The mean percentages of newly formed bone, soft tissues and residual biomaterial were respectively: 23.1%, 67.3% and 9.6% for test1; 22.8%, 67.1% and 10.1 % for test2; 25.5, 41.4%, and 33.1% for control group.

CONCLUSION AND CLINICAL IMPLICATIONS (500 CHARACTERS)
All the biomaterials tested in this study were effective for maxillary sinus augmentation; it turns out that different materials can be safely used, according to the needs and preferences of the clinicians. After 9 months of healing, the adjunct of hyaluronic acid neither improved the amount of regenerated bone nor reduced the amount of residual graft biomaterial. Nevertheless, the test groups showed a greater remodeling of the biomaterial than the control group.

A randomized clinical trial comparing 3 biomaterials for sinus augmentation- histologic outcomes.