International Journal of Oral Implantology, 02/2012

Purpose: To evaluate the medium-term effectiveness of 6.5 mm-long flapless-placed single implants immediately or early loaded at 6 weeks. Materials and methods: Thirty patients received two single NanoTite external hex Biomet 3i implants each, which were then randomly allocated to be immediately or early loaded according to a splitmouth design. Implants had to be inserted with a minimum torque of >40 Ncm. Provisional crowns were put in slight occlusal contact and replaced by definitive crowns 3 months after loading. Patients were followed for 4 years after loading. Outcome measures were implant failures, biological and biomechanical complications, peri-implant marginal bone level changes, and patient preference. Results: Twenty-nine implants were immediately loaded and 31 early loaded. Four years after loading, no drop-outs occurred. One implant failed in each group within 2 months after loading. Seven patients experienced complications at immediately loaded implants and 6 at early loaded implants. There were no statistically significant differences between groups for implant losses, complications, mean marginal bone level changes and patient preference. Conclusions: Flapless-placed 6.5 mm-long single implants can be immediately loaded and remain successful up to 4 years after loading. Even longer follow-ups are still needed to evaluate the longterm prognosis of short implants. Keywords: dental implants, early loading, flapless, immediate loading, short implants

Objectives: This randomised, controlled multicentre trial aimed at comparing two versions of a variable-thread dental implant design to a standard tapered dental implant design in cases of immediate functional loading for 36 months after loading. Materials and methods: 177 patients (325 implants) were included at 12 study centres and randomly allocated into one of three treatment groups: NAI (variable-thread design, NobelActive internal connection), NAE (variable-thread design, NobelActive external connection) and, as control, NR (standard tapered design, NobelReplace tapered groovy). Inclusion criteria concerned healed bony implant sites and feasibility for immediate loading. Clinical and radiographic examinations were performed at implant placement and after 3, 6, 12, 24 and 36 months. The outcome measures were marginal bone remodelling (primary outcome), implant survival and success, papilla score, plaque accumulation, and bleeding on probing. Results: 127 patients (NAI: 45, NAE: 41, NR: 41) were followed-up and evaluated after 36 months. No significant differences in cumulative survival rates were seen for the groups (NAI: 95.7%; NAE: 96.3%; NR: 96.6%). In all groups, bone remodelling occurred during the first 3 months, with stable or even increasing bone levels after the initial remodelling period. The bone remodelling from insertion to 36 months for the NAI group (-0.89 ± 1.65 mm) was comparable (P = 0.98) to that of the NR group (-0.85 ± 1.32 mm). The NAE group showed comparable bone remodelling during the first year, with an increase in following years resulting in significantly less overall bone loss (-0.16 ± 1.06 mm) (P = 0.041). Overall improvement in papilla size was observed in all treatment groups. Conclusions: Over 36 months, the results show stable or improving bone levels for all treatment groups after the initial bone remodelling seen during the first 3 months after placement. The variable- thread implants showed results comparable to those of standard tapered implants in cases of immediate function, and therefore can be considered as a treatment option for immediate loading. Keywords: dental implant, peri-implant bone remodelling, soft tissue evaluation, variablethread design

Aims: The objective of this randomised controlled trial was to compare the efficacy of two techniques for increasing the amount of keratinised mucosa around implants: free gingival grafts versus classic vestibuloplasty. Materials and methods: Sixty-four patients with 64 implants presenting keratinised mucosa 1.5 mm and showing signs of peri-implant mucositis were randomly assigned to two groups. Thirty-two implants received free gingival grafts (FGG group) while 32 implants were treated via vestibuloplasty (VP group). Plaque Index (PI), Gingival Index (GI), probing depth (PD) and the width of attached mucosa (WAM) were measured at baseline and 1, 3, 6 and 12 months following surgery. Results: WAM in the FGG group was significantly greater than the VP group at 3, 6 and 12 months (P = 0.000). In the FGG group, the final gain in WAM was greater (2.36 mm in FGG group, 1.15 mm in VP group) (P = 0.000) and the postoperative relapse was smaller (2.00 mm in FGG group, 3.06 mm in VP group) (P = 0.000). The VP group had higher PD values at 3, 6 and 12 months (P = 0.02, P = 0.024, P = 0.000, respectively). Conclusions: The application of FGG is a more predictable method for enhancing the width of attached mucosa in the vicinity of implants compared with classic vestibuloplasty. Keywords: attached mucosa, free gingival graft, keratinised mucosa, peri-implant health

Purpose: To evaluate whether 5 × 5 mm dental implants with a novel nanostructured calciumincorporated titanium surface could be an alternative to at least 5 × 10 mm-long implants placed in bone augmented with bone substitutes in posterior atrophic jaws. Materials and methods: Forty patients with atrophic posterior (premolar and molar areas) mandibles having 5 to 7 mm of bone height above the mandibular canal and 40 patients with atrophic maxillae having 4 to 6 mm below the maxillary sinus, were randomised according to a parallel group design to receive one to three 5 × 5 mm implants or one to three at least 5 × 10 mm-long implants in augmented bone at two centres. Mandibles were vertically augmented with interpositional bovine bone blocks and resorbable barriers and implants were placed after 4 months. Maxillary sinuses were augmented with particulated porcine bone via a lateral window covered with resorbable barriers and implants were placed simultaneously. All implants were submerged and loaded after 4 months with provisional prostheses. Four months later, definitive screw-retained or provisionally cemented metal-ceramic or zirconia prostheses were delivered. Outcome measures were prosthesis and implant failures as well as any complication. Results: Patients were followed to 4 months post-loading with the exception of one patient who underwent mandibular augmentation and had multiple complications at and after grafting, and subsequent graft failure, who did not want to go ahead with the treatment. This case was considered a complete failure. There were no statistically significant differences in prosthesis and implant failures. In mandibles, apart from the complete graft failure, one 5 × 10 mm implant failed at placement of the provisional prosthesis. In maxillae, one 5 × 5 mm implant failed with its provisional crown 3 months after loading. All complications occurred before loading. Significantly more intra- and postoperative complications occurred at both mandibular and maxillary grafted sites: 16 augmented patients were affected by complications versus 8 patients treated with short implants in the mandible (P = 0.022; difference in proportion = 0.40; CI 95% 0.12 to 0.68), and 5 sinus-lifted patients versus none treated with maxillary short implants (P = 0.047; difference in proportion = 0.25; CI 95% 0.06 to 0.44). Conclusions: Short-term data (4 months after loading) indicate that 5 × 5 mm implants achieved similar results compared to longer implants placed in augmented bone. Short implants might be a preferable choice to bone augmentation especially in posterior mandibles since the treatment is faster, cheaper and associated with less morbidity. However, 5 to 10 years of post-loading data are necessary before making reliable recommendations. Keywords: bone substitutes, inlay graft, short dental implants, sinus lift, vertical augmentation

Aim: To assess the efficacy of quick-release lornoxicam (LNX) on patient-reported acute pain after dental implant surgery. Materials and methods: The study included subjects in good general health, aged 18 to 65 and scheduled to receive a maximum of three implants in the same quadrant. Participants received either 8 mg LNX or placebo and were asked to use the medications in case of pain in the first 120 min after implant surgery. Assessment of efficacy was performed using self-assessment questionnaires for the evaluation of pain intensity and pain relief for 12 h post dosing. Patients were also asked to record the rescue analgesic number. Evaluation of patient satisfaction was assessed using a 7-point scale. Safety was evaluated by the incidence of adverse events. Results: A total of 83 (LNX/placebo, 42/41) patients who met the inclusion criteria and finished the evaluation period were included in the study. The proportion of patients experiencing postoperative pain was significantly lower in the LNX-treated group compared to the placebo group. Patients in the LNX group reported significantly higher pain relief scores than the placebo group. Twenty-nine patients in the placebo group and 6 patients in the LNX group used rescue analgesics. The number of used rescue analgesics was 1.024 ± 0.79 and 0.167 ± 0.43 in the placebo and LNX groups, respectively. The level of patient satisfaction was significantly higher in the LNX-treated patients (P = 0.007). No adverse events were reported during the study period. Conclusions: Quick-release LNX is effective in postoperative acute pain control and has a high safety profile following dental implant surgery. Keywords: dental implant, lornoxicam, NSAIDs, pain

Purpose: Our aim was to unveil the cortical neural correlates of osseoperception, i.e. the tactile sensation perceived when loading a bone-anchored implant, by taking oral implants as a model. This was performed in a cross-sectional observational study with 9 volunteering patients and 10 age-matched controls. For each patient, functional magnetic resonance imaging (fRMI) recordings were made during punctate mechanical stimulation of either teeth or osseointegrated implants in the maxillary incisor area. Materials and methods: During fMRI recordings, 1 Hz punctate tactile stimuli were applied either on a maxillary left central incisor, canine tooth or central incisor implant. A block design paradigm was used to stimulate, in 9 patients, maxillary left central incisor implants (I21-p) and maxillary left canines (T23-p). In 10 control subjects, maxillary left central incisors and canines (T21-c, T23-c) were stimulated. Random effect group analyses were performed for each stimulated site, and differences in cortical activity elicited when loading teeth or implants were examined using ANOVA. Results: As a group, patients activated somatosensory area S2 bilaterally for both I21 and T23, while controls activated S1 and S2 bilaterally for T21 and T23. At an individual level, S1 was activated by 4/9 implants, mainly on the ipsilateral side. The stimulated implants activated a larger bilateral cortical network outside the somatosensory areas: in parietal, frontal and insular lobes, the main clusters being located in the inferior frontal gyri. Stimulation of T23 in patients resulted in an activation pattern intermediate between that of the implants and that of natural teeth. Conclusion: This study demonstrates that punctate mechanical stimulation of oral implants activates both primary and secondary cortical somatosensory areas. It also suggests that brain plasticity occurs when extracted teeth are replaced by endosseous implants. This cortical activation may represent the underlying mechanism of osseoperception. Keywords: dental, fMRI, neuroplasticity, oral implant, osseoperception, periodontal, somatosensory cortex