Objectives: The objective of this 3-year split-mouth randomized controlled clinical study was to compare narrow-diameter implants (NDIs) to regular-diameter implants (RDIs) in the posterior region of the jaws (premolars and molars) in regards to (i) the marginal bone level (MBL) and (ii) implant and prosthesis survival and success rates. Material and Methods:A total of 22 patients were included in the study. Each patient received at least one implant of each diameter (Ø3.3 and Ø4.1 mm), placed either in the maxilla or mandible to support single crowns. A total 44 implants (22 NDIs and 22 RDIs) were placed and included in the study. Twenty-one implants were placed in the premolar, whereas 23 were placed in molar areas. Radiographic evaluations to access the MBL were performed immediately after implant placement, 1 and 3 years after implant loading. Peri-implant clinical variables including probing pocket depth (PPD) and bleeding on probing (BoP) were obtained after crown delivery, 1 and 3 years after loading. Furthermore, the survival and success rates of the implants and prosthesis were also evaluated.Results: Twenty patients were able to complete the study. There was no statistically significant difference regarding MBL between groups at implant placement (p = .084), 1-year (p = .794) and 3-year (p = .598) time intervals. The mean peri-implant bone loss at 3-year follow-up was −0.58 ± 0.39 mm (95% CI: −0.751 to −0.409) and −0.53 ± 0.46 mm (95% CI: −0.731 to −0.329) for NDIs and RDIs, respectively. BoP was present at 15% and 10% of NDIs and RDIs, respectively, at 3-year follow-up. PPD >5 mm was observed in 5% and 0% of the implants of NDIs and RDIs, respectively, at 3-year follow-up. At the 3-year examination, the implant success rates were in the NDIs and RDIs sites, respectively, 95% and 100%. The corresponding values for prosthesis success rates were 90% for NDIs and 95% for RDIs. Conclusion:The present study demonstrated that NDIs placed to support single crowns in the posterior region did not differ to RDIs in regards to MBL, implant survival, and success rates. K E Y W O R D Sbone resorption, dental implants, narrow diameter, radiography

Narrow diameter implants installed immediately after split-crest procedure may successfully support prosthetic rehabilitations after long-time intervals.

The present study suggests that, in a short-term follow-up, narrow diameter implants made of either titanium-zirconium alloy or commercially pure titanium may be used to support single crowns in the posterior portions of the jaws.

TiZr and cpTi NDIs presented similar outcomes after 1 year in function in the molar region of the mandible. The results suggest that TiZr and cpTi NDIs may be equally used to support single crowns in the posterior area of the mouth. However, further studies with longer follow-up periods are necessary to confirm these findings.

Anesthesia of the soft and hard tissues of the maxilla may require up to 5 injections. Thus, the aim of this study was to evaluate the anesthetic efficacy of the anterior middle superior alveolar (AMSA) and supraperiosteal injection techniques during subgingival scaling and root planing (SRP). Thirty individuals with periodontitis were scheduled for SRP on the buccal aspect of teeth in the anterior maxilla. Before SRP, on a randomly chosen side of the maxilla, the supraperiosteal injection was performed in 1 session, while the AMSA injection was conducted in the contralateral side of the same patient in another session. Immediately after each SRP session, patients rated their pain perception during the procedure with a visual analog scale. No statistically significant differences in mean pain ratings during SRP were found after both anesthetic techniques (P > .05). This preliminary study demonstrated that the AMSA and supraperiosteal injection techniques provided similar anesthetic comfort during SRP. The AMSA injection could be an alternative to anesthetize the buccal aspect of maxilla, without the undesirable effects on facial structures such as the upper lip, nostrils, and lower eyelids. However, further randomized clinical trials with larger samples are necessary to confirm such results.