Early bone formation around immediately loaded implants with nanostructured calcium-incorporated and machined surface: a randomized, controlled histologic and histomorphometric study in the human posterior maxilla.
OBJECTIVE
The aim of this randomized, controlled histologic/histomorphometric study was to compare the early bone formation around immediately loaded implants with nanostructured calcium-incorporated (NCI) and machined (MA) surface, placed in the human posterior maxilla.


METHODS
Fifteen fully edentulous patients (six males; nine females; mean age 57.9 ± 6.7 years) were selected for this study. Each patient was installed with two temporary transmucosal implants, with different surfaces: one NCI (test) and one MA (control) implant. All temporary implants were placed in the posterior maxilla, according to a split-mouth design, to help to support an interim complete maxillary denture. After 8 weeks, all temporary transmucosal implants were retrieved for histologic/histomorphometric evaluation. The bone-to-implant contact (BIC%) and the bone density (BD%) were calculated. The Wilcoxon matched-pairs signed-rank test was used to evaluate differences (BIC%, BD%) between the surfaces. The level of significance was set at 0.05.


RESULTS
Eight weeks after placement, 24 clinically stable implants (12 test, 12 control) were subjected to histologic/histomorphometric evaluation. In the MA implants, the histomorphometric evaluation revealed a mean BIC(±SD)% and BD(±SD)% of 21.2(±4.9)% and 29.8(±7.8)%, respectively. In the NCI implants, the histomorphometric analysis revealed a mean BIC(±SD)% and BD(±SD)% of 39.7(±8.7)% and 34.6(±7.2)%, respectively. A statistically significant difference was found between the two surfaces with regard to BIC% (p < 0.001), while no significant difference was found with regard to BD% (p = 0.09).


CONCLUSIONS
The NCI surface seems to increase the peri-implant endosseous healing properties in the native bone of the posterior maxilla, under immediate loading conditions, when compared with the MA surface.


CONCLUSIONS
Under immediate loading conditions in the human posterior maxilla, the nanostructured calcium-incorporated surface has led to better histologic and histomorphometric results than the machined surface; therefore, the clinical use of implants with nanostructured calcium-incorporated surface may be beneficial in the posterior maxilla, under immediate loading protocol.
Department of Surgical and Morphological Science, Dental School, University of Varese, 21100, Varese, Italy. francescoguidomangano@gmail.com.|, Piazza Trento 4, 22015, Gravedona, Como, Italy. francescoguidomangano@gmail.com.
Francesco Guido
FG
Mangano
Department of Medical, Oral, and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy.
Giovanna
G
Iezzi
Department of Periodontology, Oral Implantology Clinic, Dental Research Division, Guarulhos University, Sao Paulo, Brazil.
Jamil Awad
JA
Shibli
Department of Periodontology, Oral Implantology Clinic, Dental Research Division, Guarulhos University, Sao Paulo, Brazil.
Jefferson Trabach
JT
Pires
Department of Oral and Maxillofacial Surgery, University of Naples, Naples, Italy.
Giuseppe
G
Luongo
Department of Medical, Oral, and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy.
Adriano
A
Piattelli
Department of Dental Sciences, University Vita Salute S. Raffaele, Milan, Italy.
Carlo
C
Mangano
D000368:Aged; D000069343:Bone-Implant Interface; D002118:Calcium / Q000737:chemistry*; D015921:Dental Implants; D005260:Female; D006801:Humans; D057893:Immediate Dental Implant Loading; D007575:Jaw, Edentulous / Q000534:rehabilitation*; D008297:Male; D008437:Maxilla / Q000601:surgery*; D008875:Middle Aged; D049329:Nanostructures; D016348:Osseointegration / Q000502:physiology*; D013499:Surface Properties
D015921:Dental Implants; D002118:Calcium
Early bone formation; Human histology; Immediate loading; Implant surface