The surgical sites healed uneventfully. All animals presented appropriate healing during the first week following the surgical procedure. Post-surgical inspections for 2 weeks post-operatively indicated the absence of infection or inflammation. All implants presented osseointegration after the proposed period and were available for histological analysis.

Direct contact was observed between living bone, and all implants without the presence of soft tissues were observed in all groups. However, during the healing, the crestal areas were accompanied by decreases in the dimensions of the buccal as well as the lingual bone walls in different proportions for each group (Figs. 3 and 4). For all implants, keratinized oral epithelium was continuous with junctional epithelium facing the implants and the healing abutments. Subjacent connective tissue with a dense network of collagen fibers was observed.

After evaluating all measurements, the distance from the top of the implant collar (line A) to the first contact of the implant with the bone (line B) was measured for buccal and lingual aspect. Mean, median, standard deviation, and standard error for each group evaluated for lingual as well as buccal sites are summarized in Table 1 and showed in the Fig. 5. The buccal and lingual dimensions showed statistically significant differences at 12 weeks among the groups, which are showed in the Table 3 and the distribution data represented in the Fig. 7a. A-B distance evaluated in the group 3 was significantly lower in both buccal and lingual measured groups, whereas for group 2, A-B distance resulted higher than the other groups.

The overall mean of the tissue thickness from the top of the implant collar (line C) to the more external portion of the tissues (line D) was also calculated. Parameters such as mean, median, standard deviation, and standard error for each group evaluated for lingual as well as buccal sites are summarized in Table 2 and showed in the Fig. 6. Crestal bone height was higher for group 2 both at buccal and lingual sites. The statistical analysis also revealed differences among groups of the measured parameters, which are presented in the Table 3 and the distribution data represented in the Fig. 7b.