Survival Rate of Ultrawide Diameter Implants Placed into Molar Postextraction Sockets and in Function for Up to 144 Months

Abstract

Innovations in macroimplant design, specifically ultrawide implants 7.0 mm or greater in diameter, have allowed immediate molar replacement. This is a retrospective study assessing the survival rates of ultrawide diameter implants (7.0, 8.0, 9.0 mm) immediately placed into molar extraction sockets. Implants were followed up to 144 months postplacement. Materials and methods: A retrospective study was conducted of all patients treated in a private surgical practice between January 1, 2008 and December 31, 2020, who received ultrawide dental implants (7.0, 8,0, 9.0 mm.) placed immediately into molar extraction sockets. Wide diameter healing abutments were placed on all implants at the time of surgery. Abutments and crown restorations were fabricated after at least 4 months of unloaded healing. Patient age, sex, implant location and implant diameters were examined for survival. Insertion torque values at the time of placement and time in function were also evaluated. Biometric statistics were computed with p-values (<0.05. Descriptive and bivariate statistics were computed; p-values were set at 0.05. Results: Five hundred forty-four patients (225 males; 319 females) average age 62.5 years (range 27 to 95) had 563 implants placed. Five hundred thirty-five of five hundred sixty-three (535/563) implants survived; 28 failed [clinical survival rate (CSR) 95.03%]. Number and time in function were: 0 to 12 years 100%; 0 to 9 years 85%; 0 to 6 years 69%; 0 to 3 years 35% or 10 to 12 years 16%; 7 to 9 years 16%; 4 to 6 years 34%; 0 to 3 years 35%. No significant differences were found between sex and implant failures (p = 0.22). Maxillary (266/285; 93.3%) and mandibular (269/278; 96.8%) implant CSRs were not significantly different. Three implant diameters were used: 7.0 mm (206/563) [36.6%]; 8.0 mm (267/563) [47.4%]; 9.0 mm (90/563) [15.9%]. Clinical survival rates were: 7.0 mm (201/206) [97.6%]; 8.0 mm (252/267) [94.4%]; 9.0 mm (82/90) [91.1%]. Mean age for patients with failed implants did not show any significant differences (p = 0.1398). Fifteen of the 28 failed implants failed within 120 days of surgical placement (prior to definitive restoration; [53.6%]; 4 implants failed between 4 and 12 months [14.3%]; 9 implants failed at least 1-year postloading [32.1%]. Conclusions:The results of this long-term retrospective study regarding ultrawide diameter implants suggested that these implants were viable treatment options for immediate molar replacement following tooth extraction in either jaw with an unloaded healing protocol. High clinical survival rates were reported over a 144-month (12-year) timeframe.

Guidance and rationale for the immediate implant placement in the maxillary molar

“…For the type III socket and re-installation case, we highly suggest a wide-or ultra-wide-diameter implant. The high survival rate of such implants (diameter greater than 6 mm) placed immediately has been reported in several studies, with the longest follow-up period of up to 12 years [38][39][40] . In our case, the type III socket benefited from the ability of an ultra-wide-diameter implant to engage the bony walls of the extraction socket.…”

“…In our case, the type III socket benefited from the ability of an ultra-wide-diameter implant to engage the bony walls of the extraction socket. Other benefits offered by the ultra-wide diameter are preservation of bone and soft tissue, reduced buccal bone resorption, and better suitability in cases of sinus pneumatization 38 . As a wide-diameter implant is appropriate for posterior regions with poor bone quality, it also has been suggested for replacing previously failed implants, such as in our re-installation case 2 , 38 .…”

Effectiveness of ultra-wide implants in the mandibular and maxillary posterior areas: a 5-year retrospective clinical study

“…However, if the bone width is insufficient, bony dehiscence may occur frequently due to the excessive pressure applied to the buccal bone with resulting gingival recession 5 . According to Will and Drago 6 , the 120 year survival rate of implants with diameters of 7 mm is 97.6%. Similarly, according to Wadhwa et al 7 , the 6-year survival rate of implants with a diameter of 6 mm or more is 97.29%, higher than the standard diameter.…”