Abstract
Aim To evaluate the primary and secondary stability of implants in the posterior maxilla. Methods Patients were allocated into three groups: (A) native bone, (B) partially regenerated bone, and (C) nearly totally regenerated bone. Insertion torque (IT) and implant stability quotient (ISQ) were measured at placement, to evaluate whether satisfactory high primary stability (IT ≥ 45 N/cm; ISQ ≥ 60) was achieved; ISQ was measured 15, 30, 45, and 60 days after placement, to investigate the evolution to secondary stability. Results 133 implants (Anyridge®, Megagen) were installed in 59 patients: 55 fixtures were placed in Group A, 57 in Group B, and 21 in Group C. Fifty-two implants had satisfactory high primary stability (IT ≥ 45 N/cm; ISQ ≥ 60). A positive correlation was found between all variables (IT, ISQ at t = 0, t = 60), and statistically higher IT and ISQ values were found for implants with satisfactory high primary stability. Significant differences were found for IT and ISQ between the groups (A, B, and C); however, no drops were reported in the median ISQ values during the healing period. Conclusions The evaluation of the primary and secondary implant stability may contribute to higher implant survival/success rates in critical areas, such as the regenerated posterior maxilla. The present study is registered in the ISRCTN registry with ID ISRCTN33469250.
Highlights
The aforementioned drop was not observed and the implant stability quotient (ISQ) values stayed very stable in the first two months of the healing time. This result is the most important element emerging from the study, since the absence of drop in the implant stability during the first healing period may potentially contribute to higher implant survival/success rates in critical areas, such as the regenerated posterior maxilla. This excellent result certainly depends in the first place on the high primary stability obtained at implant placement: this study has shown that there is a linear correlation between the values of insertion torque (IT) and ISQ at insertion and ISQ during the healing period, for all the fixtures and for the fixtures with satisfactory high primary stability
133 implants were installed in 59 patients in the posterior areas of the maxilla of three different types of patients: patients with native bone (Group A, 55 implants), patients with partially regenerated bone (Group B, 57 implants), and patients with nearly totally regenerated bone (Group C, 21 implants)
The primary implant stability was measured at placement, by means of insertion torque (IT) and implant stability quotient (ISQ)
Summary
Dental implants are considered the best treatment option to replace nonrestorable or lost teeth: both professionals and patients are convinced of the validity of this treatment procedure that shows reliable long-term results [1, 2].In the posterior maxilla, the rehabilitation of patients with implant supported fixed partial prostheses or single crowns is a safe and effective procedure, as demonstrated by several clinical studies [3, 4].In cases of advanced or severe vertical and/or horizontal bone defects, regenerative surgical techniques are essential to correct the initial anatomical situation, to allow the proper placement of dental implants in the posterior maxilla [5].Among these regenerative techniques, maxillary sinus augmentation [3,4,5,6,7], guided bone regeneration (GBR) [8], and split-crest techniques [9] are the most commonly used procedures to restore the ideal anatomical bone conditions and to allow simultaneous and/or subsequent placement of dental implants.in recent years, it has been shown that the success of fixed rehabilitation with dental implants depends on the quantity (volume) of bone available for implant placement, and on the quality of this bone [10, 11].The assessment of the quality of the bone structure should be considered essential, prior to implant placement [11, 12]. In cases of advanced or severe vertical and/or horizontal bone defects, regenerative surgical techniques are essential to correct the initial anatomical situation, to allow the proper placement of dental implants in the posterior maxilla [5]. Among these regenerative techniques, maxillary sinus augmentation [3,4,5,6,7], guided bone regeneration (GBR) [8], and split-crest techniques [9] are the most commonly used procedures to restore the ideal anatomical bone conditions and to allow simultaneous and/or subsequent placement of dental implants. The achievement and maintenance of an adequate implant stability are fundamental prerequisites for the longterm positive outcomes of osseointegrated implants [13, 14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
