Computer-Aided Surgery and Immediate Loading to Rehabilitate Complete Arch with Four Dental Implants and Fixed Screw-Retained Prosthesis Up to 4 Years in Function: A Retrospective Study.

PURPOSE: The aim of this study was to analyze retrospectively the clinical reliability of complete-arch rehabilitations with screw-retained fixed prostheses supported by four dental implants inserted with a fully guided surgical protocol. MATERIALS AND METHODS: All the implants were placed between December 1, 2015, and April 30, 2019. Digital implant surgical planning was performed for all the complete-arch rehabilitations, and then, fully guided surgery was performed. The fixed provisional prostheses were delivered the day of the surgery and replaced by definitive prostheses after the healing period. Patients were followed up to determine survival of the implants and success of the overall treatment. RESULTS: A total of 160 implants were positioned in 37 patients, with three patients receiving rehabilitations in both arches. A total of 40 complete-arch rehabilitations were performed, 26 in the maxilla and 14 in the mandible. Only five implants failed, resulting in an overall implant survival rate of 96.9%. No definitive prostheses failed, resulting in a 100% prosthetic success rate. The failed implants were successfully replaced before definitive prostheses were made, resulting in an overall treatment success of 100%. CONCLUSION: Within the limitations of this study, digital planning and guided surgery to perform complete-arch rehabilitations on four dental implants seems to be a valid treatment option. However, several prospective studies with longer follow-up are needed to achieve more predictable results.

Short Dental Implants (≤ 6 mm) to Rehabilitate Severe Mandibular Atrophy: A Systematic Review.

PURPOSE: This study aimed to assess the survival rate, marginal bone levels, and prosthetic success of short implants when placed in posterior areas of severely reabsorbed mandibles. MATERIALS AND METHODS: A systematic review was performed of all randomized controlled trials with at least 10 patients with a control group where bone augmentations were performed that were published between January 2015 and February 2020. From 77 pertinent studies, 14 full-text publications were studied, and 6 studies fulfilled the inclusion criteria. RESULTS: The implant survival rates of short dental implants ranged from 92% to 96.9% with a follow-up from 1 to 5 years, and the prosthetic success rate ranged from 90% to 100% during the same follow-up. The mean marginal bone level values of involved short implants ranged from -0.51 to -2.30 mm. CONCLUSION: The obtained data showed that short dental implants are a valid therapeutic choice to rehabilitate severe mandibular atrophy in the medium to long term.

Digital Workflow to Merge an Intraoral Scan and CBCT of Edentulous Maxilla: A Technical Report.

Rehabilitation of edentulous maxilla is a challenging procedure. This technical report describes a new method to superimpose intraoral optical scanning of edentulous maxilla and the CBCT scan using a modified radiographic template. Digital data obtained can be exported and merged into 3D computer guided surgery software. The described technique can increase the predictability and the precision of complete-arch rehabilitation planned by means of computer-assisted implant surgery.

Unusual Case of Osseointegrated Dental Implant Migration into Maxillary Sinus Removed 12 Years after Insertion.

Displacement of dental implants into the maxillary sinus is not an uncommon event in implant dentistry and may lead to serious complications, such as sinusitis. To avoid systemic problems, performing the removal of the foreign body as soon as possible is suggested. Despite the fact that early implants dislocation has been reported several times, late migration into maxillary sinus has been described by just a few studies. The purpose of this study was to report a rare case of dental implant migration into maxillary sinus after 12 years of function. A 61-year-old woman came to our attention in June 2015 after being visited by an otolaryngologist and being diagnosed with sinusitis and presence of a foreign body into the right maxillary sinus. A panoramic radiograph and a CT scan showed the migration of dental implant sited in 1.6 positions into the maxillary sinus. The implant was removed following a Caldwell-Luc procedure under local anesthesia. Postoperative course was uncomplicated and the patient reported no symptoms of sinusitis after 12 months of follow-up.

Dental implants placement in conjunction with osteotome sinus floor elevation: a 12-year life-table analysis from a prospective study on 588 ITI implants.

OBJECTIVES: The purpose of this prospective study was to evaluate the clinical success of placing ITI dental implants in the posterior maxilla using the osteotome technique. MATERIAL AND METHODS: All implants were placed following a one-stage protocol (elevating the sinus floor and placing the implant at the same time). Five hundred and eighty-eight implants were placed in 323 consecutive patients with a residual vertical height of bone under the sinus ranging from 6 to 9 mm. The mean observation follow-up period was 59.7 months (with a range of 12-144 months). This prospective study not only calculated the 12-year cumulative survival and success rates for 588 implants by life-table analysis but also the cumulative success rates for implant subgroups divided per implant length and the percentage of sinus membrane perforation were evaluated. RESULTS: The 12-year cumulative survival and success rates were 94.8% and 90.8%, respectively. The analysis of implant subgroups showed slightly more favourable cumulative success rates for 12 mm long implants (93.4%) compared with 10 and 8 mm long implants (90.5% and 88.9%, respectively). During the study period, only 13 perforations of the Schneiderian membrane were detected with a perforation rate of 2.2% (13 perforations/601 treated sites). Ten perforations out of 13 were caused during the first half of the study period and of these, seven were detected during the first 3 years of this prospective study. CONCLUSION: Based on the results and within the limits of the present study, it can be concluded that ITI implant placement in conjunction with osteotome sinus floor elevation represents a safe modality of treating the posterior maxilla in areas with reduced bone height subjacent to the sinus as survival and success rates were maintained above 90% for a mean observation period of approximately 60 months. Shorter implants (8 mm implants) did not significantly fail more than longer ones (10 and 12 mm implants): the differences were small compared with the number of events; hence, no statistical conclusion could be drawn. But, from the clinical point of view, the predictable use of short implants in conjunction with osteotome sinus floor elevation may reduce the indication for complex invasive procedures like sinus lift and bone grafting procedures.

Inferior alveolar nerve transposition in conjunction with implant placement.

PURPOSE: The aim of this prospective study was to determine the incidence of neurosensory disturbance and the cumulative survival and success rates of ITI solid-screw implants placed in conjunction with an inferior alveolar nerve (IAN) transposition technique. MATERIALS AND METHODS: 46 ITI implants were placed in 15 patients following transposition of the IAN. In 4 patients nerve transpositioning was performed bilaterally, so a total of 19 IAN mobilization surgeries were performed. Neurosensory dysfunction was objectively evaluated by using light touch (LT), pain (PT), and 2-point discrimination (2-DT) tests. In addition, patients were asked to answer a short questionnaire to investigate individual feelings of discomfort and advantages related to this surgical technique. The mean follow-up period was 49.1 months (range, 12 to 78 months). RESULTS: The cumulative implant survival and success rates were 95.7% and 90.5%, respectively. Only 2 implants were lost. Neurosensory disturbance (ie, disturbance registered by the LT, PT, and 2-DT tests) was experienced in 4 of 19 cases. However, at the time of data analysis (12 to 78 months after surgery), all patients indicated that they would go through the surgery again. DISCUSSION: The IAN transposition technique, when used in the severely atrophied posterior mandible, allowed placement of implants with adequate length and good initial stabilization. All patients felt that they had received significant benefits from their new prostheses. CONCLUSION: Based on the results of the present study, it can be concluded that lateral nerve transposition can be used as a surgical procedure to enable ITI implant placement in the severely resorbed posterior mandible.

Surgical advantages with ITI TE implants placement in conjunction with split crest technique. 18-month results of an ongoing prospective study.

Implant rehabilitation of the edentulous maxilla may be somewhat problematic because of anatomic situations involving insufficient bone thickness. One approach in this situation is localized ridge augmentation with the split crest technique. This surgical approach allows the external cortical plate of the maxilla to be moved in a labial direction to gain an increase in width to introduce implants of appropriate diameter. This ongoing prospective study evaluated: (i) the surgical advantages that the new ITI TE implants have showed compared with the ITI standard solid-screw implants when placed in conjunction with the split crest technique and (ii) the implant success rate associated with 42 ITI TE implants and 40 ITI standard solid-screw implants placed in 40 patients in conjunction with the split crest technique. ITI TE implants have shown direct and indirect advantages in reducing the risk of fracture of the labial cortical plate during all the three fundamental surgical steps of this technique: (a) the ridge expansion with osteotomes; (b) implant site preparation with drills and (c) implant insertion. The overall success rates of ITI TE implants and standard screw implants were 100% and 95%, respectively. Based on the preliminary results of the present study, it can be concluded that ITI TE implants inserted in conjunction with split crest technique seem to be a promising surgical procedure to treat selected anatomic situations involving insufficient maxillary bone thickness.

A long-term follow-up study of non-submerged ITI implants in the treatment of totally edentulous jaws. Part I: Ten-year life table analysis of a prospective multicenter study with 1286 implants.

In this prospective multicenter study, non-submerged ITI implants were followed in order to evaluate their long-term prognosis in fully edentulous jaws. A total of 1286 implants were inserted in 233 consecutive patients and, after a healing period of three to six months, the successfully integrated implants were restored with 163 overdentures and 95 fixed full-arch bridges. This prospective study not only calculated the 10-year cumulative survival and success rates for the 1286 implants by life table analysis, but also evaluated the actual survival and success rates for 498 implants after at least five years of functional loading. In addition, cumulative success rates were calculated for implant subgroups according to implant length and location. Additional analyses were performed to evaluate the estimated and actual survival and success rates of the implants in relation to various prosthetic rehabilitation techniques. The 10-year cumulative survival and success rates were 95.9% and 92.7%, respectively. The actual 5-year survival and success rates of the first 498 implants that were inserted were 97.7% and 95.0%, respectively. The analysis of implant subgroups showed slightly more favourable cumulative success rates for 12 mm long implants (93%), in comparison to 10 mm and 8 mm long implants (91.6% and 89.6%, respectively). The cumulative success rate for mandibular implants (approximately 94%) was also more favourable than that for maxillary implants (approximately 91%). Patients who were loaded with both maxillary and mandibular prostheses maintained success rates well above 90%; while only implants that were inserted to support maxillary overdentures that were retained by Dolder bars showed a success rate below 90%.