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Objective Materials and Methods Results Conclusion To compare fully guided flapless implant surgery using a light‐cured surgical guide (FG group) with partially guided open flap surgery (PG group) in the posterior maxilla when performing simultaneous sinus floor elevation in terms of the accuracy, time requirements, and patient/clinician‐reported outcomes (PROMs and CROMs).In this study, 56 tissue‐level implants were placed with crestal sinus floor elevation in 56 patients at single‐tooth sites, with 28 implants allocated to the PG group and 28 to the FG group. The deviations of the placed implants from the virtually planned positions were measured at the implant platform and apex and for the angular deviation. The presurgical preparation time and the duration of surgery were measured. PROMs and CROMs were made by administering questionnaires at multiple time points.Horizontal deviations at the platform and apex and the angular deviation were significantly smaller in the FG group than the PG group (p < .05). Presurgical preparation and surgery times were significantly shorter in the FG group (p < .001). Patient satisfaction and willingness to receive repeat treatment were significantly better in the FG group than in the PG group (p < .005 and .025, respectively). Clinicians were more satisfied in the FG group than the PG group (p < .05).When placing an implant with sinus floor elevation, the flapless approach using a fully guided surgical system can be more accurate, faster, and increase the satisfaction of both the clinician and patient compared to the partially guided surgery. [ABSTRACT FROM AUTHOR]

Objective: The objective was to assess the one year implant treatment outcome and patient‐related outcome measures (PROMs) following maxillary sinus floor augmentation (MSFA) with autogenous bone graft (ABG) from the zygomatic buttress (control) compared with 1:1 mixture of ABG and anorganic porcine bone mineral (APBM) (Test I) or biphasic bone graft material (BBGM) (Test II). Materials and Methods: Sixty healthy patients (34 females, 26 males) were randomly allocated to either control or test groups. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of peri‐implant tissue, peri‐implant marginal bone loss, frequency of complications, and PROMs using Oral Health Impact Profile‐14 combined with questionnaire assessing patient perception of peri‐implant soft tissue, prosthetic solution, implant function, and implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was.05. Results: All suprastructures and implants were well‐functioning after one year of functional implant loading. There was no significant difference between control and test groups in any of the applied outcome measures. The implant stability significantly increased from implant placement to abutment connection within all groups (p <.001). High patient satisfaction and significant improvement in oral health‐related quality of life was also reported within all groups. Conclusion: This study demonstrates that MSFA with composite grafts containing minimal amounts of ABG reveals comparable implant treatment outcomes as compared with ABG alone, after one year of functional implant loading. Extensive ABG harvesting in conjunction with MSFA therefore seems not to be needed. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of reconstructive peri‐implantitis treatment. Materials and Methods: Forty participants, with peri‐implantitis and a contained intraosseous defect, were randomized to access flap (control) or access flap with xenograft and collagen membrane (test). All received systemic antimicrobials. Blinded examiners recorded probing depths (PD), bleeding and suppuration on probing (BOP & SOP), soft tissue levels, and marginal bone levels (MBL) at baseline and 12 months. Patient reported outcomes were recorded. The primary outcome was PD change. Results: All 40 participants (40 implants) completed the 12‐month study. The mean (standard deviation) PD reduction (deepest site) was 4.2 (1.8) mm in the control and 3.7 (1.9) mm in the test group. MBL gain (deepest site) was 1.7 (1.6) mm in the control and 2.4 (1.4) mm in the test group. Absence of BOP & SOP was observed at 60% of both control and test implants. Buccal recession was 0.9 (1.6) mm in the control and 0.4 (1.1) mm in the test group. A successful outcome (absence of PD ≥ 5 mm with BOP, absence of SOP and absence of progressive bone loss) was achieved for 90% of the control and 85% of test group implants. No statistically significant differences in clinical or radiographic parameters were found between treatment groups. 30% of participants experienced mild gastro‐intestinal disturbances. Reporting followed CONSORT guidelines. Conclusion: Similar clinical and radiographic improvements at 12 months were observed with high levels of patient satisfaction for both the access flap and xenograft covered by collagen membrane groups. Registered clinical trials.gov. ID:NCT03163602 (23/05/2017). [ABSTRACT FROM AUTHOR]

Objective: The aims of this clinical trial were to evaluate the radiographic dimensional changes in alveolar ridge and patient‐reported outcomes following tooth extraction and alveolar ridge preservation (ARP) using either deproteinized bovine bone mineral (DBBM) with EMD or DBBM alone. Methods: Participants requiring at least one posterior tooth extraction and ARP were randomly allocated into two treatment groups: ARP using either DBBM with EMD or DBBM alone. Cone‐beam computed tomography (CBCT) images were recorded immediately prior to extraction and at 6 months. Changes in alveolar ridge height (ARH) and alveolar ridge width (ARW) at 1, 3, and 5 mm were recorded. Results: A total of 18 participants with 25 preserved sites were evaluated. ARH and ARW changed significantly from baseline to 6 months for both treatment groups but the difference between the groups was not statistically significant over the 6‐month follow‐up period (ARH: DBBM/EMD 1.26 ± 1.53 mm vs. DBBM 2.26 ± 1.60 mm; ARW‐1 DBBM/EMD 1.98 ± 1.80 mm vs. DBBM 2.34 ± 1.89 mm). A significant difference, favoring DBBM with EMD group, was observed in percentage of sites that had less than 1 mm loss in ARH (54.5% sites in DBBM/EMD group vs. 14.3% sites in DBBM alone group). The participants' perception of bruising, bleeding, and pain in the first two postoperative days was significantly in favor of DBBM alone group. Conclusions: There were no significant differences in radiographic mean measurements of ARH and ARW following ARB with DBBM and EMD or DBBM alone. [ABSTRACT FROM AUTHOR]

Objectives: To compare erythritol air polishing with implant surface cleansing using saline during the surgical treatment of peri‐implantitis. Material and Methods: During a resective surgical intervention, implant surfaces were randomly treated with either air polishing (test group n = 26 patients/53 implants) or saline‐soaked cotton gauzes (control group n = 31 patients/ 40 implants). Primary outcome was change in mean bleeding on probing (BoP) from baseline to 12 months follow‐up. Secondary outcomes were changes in mean suppuration on probing (SoP), plaque score (Plq), probing pocket depth (PPD), marginal bone loss (MBL), periodontal full‐mouth scores (PFMS), and levels of 8 classical periodontal pathogens. Clinical and radiographical parameters were analyzed using multilevel regression analyses. Microbiological outcomes were analyzed using the Mann–Whitney U test. Results: No differences between the test and control group were found for BoP over 12 months of follow‐up, nor for the secondary parameters Plq, PPD, and MBL. Between both groups, a significant difference was found for the levels of SoP (p = 0.035). No significant effect on microbiological levels was found. A total number of 6 implants were lost in the test group and 10 in the control group. At 1‐year follow‐up, a successful treatment outcome (PPD<5 mm, max 1 out of 6 sites BoP, no suppuration and no progressive bone loss >0.5 mm) was achieved for a total of 18 implants (19.2%). Conclusions: Erythritol air polishing as implant surface cleansing method was not more effective than saline during resective surgical treatment of peri‐implantitis in terms of clinical, radiographical, and microbiological parameters. Both therapies resulted in low treatment success. Trial registry: https://www.trialregister.nl/ Identifier: NL8621. [ABSTRACT FROM AUTHOR]

Objective: The objective was to assess patient's perception of recovery after maxillary sinus membrane elevation (MSME) and blood coagulum (test) compared with maxillary sinus floor augmentation (MSFA) and 1:1 mixture of autogenous bone graft from the buccal antrostomy and deproteinized porcine bone mineral (DPBM) (control). Materials and methods: Forty healthy patients were randomly allocated to test or control. Oral health‐related quality of life (OHRQoL) was evaluated by Oral Health Impact Profile‐14 (OHIP‐14) at enrollment and 1 week postsurgical. Recovery was estimated by questionnaires and visual analog scale assessing pain, social and working isolation, physical appearance, eating and speaking ability, diet variations, sleep impairment, and discomfort after 1 week and 1 month. Mean differences were expressed with 95% confidence interval (CI). Association between OHRQoL and recovery was estimated. p‐value below.05 was considered statistically significant. Results: Maxillary sinus membrane elevation revealed 2.1 less days of pain (p =.03, 95% CI: 0.2–4.1) and 1.2 days of sick leave (p =.01, 95% CI: 0.3–2.1) compared with MSFA. No significant difference was observed in eating and speaking ability, physical appearance, work performance, and sleep impairment. No significant association between impaired OHRQoL and recovery was observed. Females reported 4.77 higher OHIP‐14 score compared with males (p =.01, 95% CI: 1.60–7.94), while association between age and OHIP‐14 was −0.10 (p =.28, 95% CI: −0.28 to 0.08). Conclusion: Maxillary sinus membrane elevation revealed significantly less days of pain and sick leave compared with MSFA. Harvesting of autogenous bone graft seems, therefore, to have a significant impact on perception of recovery. [ABSTRACT FROM AUTHOR]

Objective: To compare fully guided with conventionally guided implant surgery performed by dental students in terms of deviation of actual implant position from an ideal implant position. Materials and methods: Twenty‐five patients in need of 26 straightforward implant‐supported single crowns were randomly allocated to a fully guided (FG, n = 14) or a conventionally guided (CG, n = 12) implant surgery. In the preoperative CBCTs, 3 experienced investigators placed a virtual implant in the ideal position, twice, allowing deviational analysis in the facio‐lingual (coronal) and mesio‐distal (sagittal) planes for 7 parameters. Facio‐lingual crestal deviation, facio‐lingual apical deviation, facio‐lingual angular deviation, mesio‐distal crestal deviation, mesio‐distal apical deviation, mesio‐distal angular deviation, and vertical deviation between the ideal, virtually placed position and actual implant position for the FG and CG groups were compared statistically (p <.05). Results: Statistically significant differences between ideal and actual implant position were only seen for the facio‐lingual apical deviation (p =.047) and for the facio‐lingual angular deviation (p =.019), where the CG group deviated more from the ideal position than the FG group. The 5 other examined variables did not show any significant differences, and none of the implants in the FG group and CG group were placed in conflict with the clinical guidelines. Conclusions: The present study reported no difference in 5 out of 7 deviational parameters concerning actual implant position in relation to ideal implant position between a FG and CG implant placement protocol performed by dental students. Facio‐lingual angular deviation and apical deviation were lower, when a FG protocol was followed. All implants were positioned according to clinical guidelines. [ABSTRACT FROM AUTHOR]

Objectives: To compare erythritol air polishing with piezoelectric ultrasonic scaling in the non‐surgical treatment of peri‐implantitis. Material and methods: Eighty patients (n = 139 implants) with peri‐implantitis (probing pocket depth (PPD) ≥5 mm, marginal bone loss (MBL) ≥2 mm as compared to bone level at implant placement, bleeding, and/or suppuration on probing (BoP/SoP)) were randomly allocated to air polishing or ultrasonic treatment. The primary outcome was mean BoP (%) at 3 months after therapy (T3). Secondary outcomes were mean SoP (%), plaque score (Plq) (%), PPD (mm), MBL (mm), full mouth periodontal scores (FMPS) (%), levels of 8 classical periodontal pathogens, and treatment pain/discomfort (Visual Analog Scale, VAS). Patients who were considered successful at T3 were additionally assessed at 6, 9, and 12 months. Differences between both groups were analyzed using multilevel statistics. Results: Three months after therapy, no significant difference in mean BoP (%) between the air polishing and ultrasonic therapy was found (crude analysis β (95% CI) −0.037 (−0.147; 0.073), p =.380). Neither secondary outcomes SoP (%), Plq (%), PPD (mm), MBL (mm), FMPS (%), and periodontal pathogens showed significant differences. Treatment pain/discomfort was low in both groups (VAS score airpolishing group 2.1 (±1.9), ultrasonic 2.6 (±1.9); p =.222). All successfully treated patients at T3 (18.4%) were still considered successful at 12‐month follow‐up. Conclusions: Erythritol air polishing seems as effective as piezoelectric ultrasonic scaling in the non‐surgical treatment of peri‐implantitis, in terms of clinical, radiographical, and microbiological parameters. However, neither of the proposed therapies effectively resolved peri‐implantitis. Hence, the majority of patients required further surgical treatment. [ABSTRACT FROM AUTHOR]

Objective: The aim of this multicenter, randomized controlled trial was to compare the clinical and radiographic outcomes of 6‐mm or 11‐mm implants, placed in the posterior maxilla and mandible, during a 5‐year follow‐up period. Materials and methods: Ninety‐five patients with adequate bone height for 11‐mm implants, were randomly allocated to a 6‐mm group (test group with short implants) or an 11‐mm group (control group with standard‐length implants). Two or three implants of the same length were placed in each patient and after 6 weeks loaded with a splinted provisional restoration. This was followed by definitive splinted restoration 6 months after implant placement. Clinical and radiographic parameters, including the occurrence of complications were recorded. Results: A total of 49 patients were enrolled to receive 6‐mm implants (n = 108) and 46 patients to receive 11‐mm implants (n = 101). Three implants (two of 6 mm and one of 11 mm in length) were lost before loading and one 6‐mm implant after 15 months of function, and one 11‐mm implant was lost during the first year of function. The 5‐year survival rates were 96.0% and 98.9% in the 6‐mm and 11‐mm group, respectively. The mean marginal bone level changes 5 years post‐loading were 0.01 ± 0.45 mm (bone gain) in the 6‐mm group and −0.12 ± 0.93 mm (bone loss) in the 11‐mm group (p =.7670). Clinical parameters, including plaque, bleeding on probing and pocket probing depth were not significantly different between the groups, and also technical complications were low. Conclusion: The clinical and radiographic outcomes of 6‐mm short and 11‐mm standard‐length implants were not different during a 5‐year evaluation period. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this randomized, controlled, parallel‐arm study was to evaluate the (a) radiographic bone dimensional changes, (b) postoperative discomfort, and (c) early soft tissue wound healing outcomes, following extraction of maxillary anterior teeth (central and lateral incisors) and treatment with alveolar ridge preservation (ARP) with and without the adjunctive use of enamel matrix derivative (EMD). Methods: Thirty extraction sockets were randomly assigned to two groups: deproteinized bovine bone mineral with 10% collagen covered with collagen membrane with the adjunctive use of EMD (test group) and without EMD (control group). Bone dimensional changes were measured using cone beam computed tomography at 3 and 5 months after ARP. The severity and duration of pain and swelling were evaluated using self‐reported questionnaires, and soft tissue wound healing outcomes were assessed clinically. Chi‐square tests and t tests were conducted to compare differences between the two groups. Results: Radiographic and clinical analyses showed no significant differences in horizontal and vertical bone dimensional changes and soft tissue wound healing outcomes (including spontaneous bleeding, persistent swelling, and ulceration) between the two groups. There were no significant differences in the severity of pain and swelling between the two groups, but the durations of pain (difference [df] = 1.20, 95% CI = 0.33–2.06; p =.008) and swelling (df = 1.06, 95% CI = 0.11–2.01; p =.029) were significantly reduced in the test group. Conclusion: Alveolar ridge preservation with the adjunctive use of EMD reduced the durations of postoperative pain and swelling following maxillary anterior teeth extraction. [ABSTRACT FROM AUTHOR]

Objectives: To compare the clinical treatment outcomes of maxillary four‐implant retained overdentures with either splinted (bar) attachments or non‐splinted (ball) attachments. Material and Methods: Forty participants who were dissatisfied with their existing conventional maxillary complete dentures were included in this randomized controlled trial. Six months after implant placement, a definitive prosthesis was inserted. Implant success, condition of peri‐implant tissue, prosthodontic maintenance and complications, and patient satisfaction were assessed. Outcomes were recorded at baseline, prosthesis delivery, and at 3 and 12 months following prosthesis delivery, and a statistical analysis was performed. Results: Thirty‐two of the forty patients completed the 1‐year follow‐up and had their treatment outcomes evaluated. The mean marginal bone loss after 1 year of loading was 0.34 ± 0.88 mm, and there were no significant differences between the two groups. Plaque index, gingival index and bleeding on probing were significantly higher in the bar group (p<.001), and the implant success rate of the bar group was significantly lower than that of the ball group (p=.028). The most frequent prosthodontic maintenance and complication issue was the need to change the bar clip or O‐ring as a result of retention loss. Patient satisfaction did not differ between the two groups except for aesthetics at 3 months. Conclusions: Within the limitations of this study, the maxillary 4‐implant retained overdenture exhibited predictable results regardless of the attachment systems (ball or bar) in the 1‐year follow‐up period. The bar group was more vulnerable than the ball group with respect to maintaining peri‐implant tissue health. [ABSTRACT FROM AUTHOR]

Objectives: To test whether block bone substitute used for guided bone regeneration (GBR) of peri‐implant defects leads to different thickness of the augmented hard tissue than particulate bone substitute. Material and methods: In 24 patients, 24 two‐piece dental implants were placed >4 months after tooth extraction. Following random allocation, 12 peri‐implant bone dehiscences were grafted with an individually shaped block of deproteinized bovine‐derived bone mineral (DBBM) and 12 bone dehiscences with particulate DBBM. All the sites were covered with a collagen membrane stabilized with resorbable pins. Immediately after wound closure and after 6 months, the horizontal thickness (HT) of the augmented hard tissue was measured at the level of implant shoulder using ‐computed tomography. Results: After wound closure, the median HT measured 3.35 mm (mean: 3.38) in the block group and 2.85 mm (mean: 2.73) in the particulate group. At 6 months, the median HT decreased to 2.90 mm (mean: 2.71) in the block group and to 0.2 mm (mean: 0.52) in the particulate group. This difference was statistically significant (p < .001). Conclusions: Block bone substitute used for GBR of peri‐implant defects was superior to particulate bone substitute regarding the dimension of the augmented hard tissue after 6 months of healing. [ABSTRACT FROM AUTHOR]

Objectives: To follow‐up the radiographic bone level changes and the clinical outcomes of immediately provisionalized and conventionally restored implants with a hydrophilic surface following 5 years of function. Materials and methods: This was a 5‐year follow‐up of a prospective, randomized, single‐blind controlled study involving 16 of the 24 originally recruited patients in need of a single‐tooth replacement in the esthetic area. Implants were either immediately provisionalized with a non‐occluding temporary crown (test group, n = 7), or left without a crown (control group, n = 9). In both groups, the definitive restoration was placed 16 weeks after implant placement. Radiographic and clinical parameters were evaluated at 36, 48, and 60 months post‐implant placement, together with implant survival and success rates. The esthetic outcomes were measured with the Papilla Fill Index (PFI) and the Pink Esthetic Score (PES). Results: At 60 months, similar peri‐implant bone loss was observed in the test (−0.42 mm ±0.17 mm) and in the control (−0.37 mm ±0.35 mm) groups. A tendency for an improved esthetic outcome from implant loading to the subsequent follow‐ups was noticed in both groups. Both groups presented with high levels of long‐term implant survival and success. Conclusions: This study supports non‐functional immediate provisionalization as a viable long‐term option for the management of single‐tooth implants in the esthetic area. However, the small sample size does not allow statistical inference at 60 months of follow‐up and future adequately powered studies are warranted. [ABSTRACT FROM AUTHOR]

Aim To present 10-year cone beam CT ( CBCT) data on the fate of buccal bone at single-tooth implants placed early, delayed, or late after tooth extraction. Material and methods Sixty-three of 72 patients, originally randomly allocated to three equal-size groups, received a single-tooth implant on average 10 days (Ea; N = 22), 3 months (De; N = 22), or 1.5 years (La; N = 19) after tooth extraction. Healing abutments were mounted after a 3-month period of submerged healing and metalceramic crowns were cemented after one additional month. At the second stage surgery, presence of buccal bone defects (dehiscences or intrabony) and their dimensions were registered. CBCT scans recorded with a Scanora® 3D unit and standardized periapical ( PA) radiographs of the implants were obtained at the 10-year control. Interproximal bone levels (i.e., the distance from the implant platform to the first bone-to-implant contact; BIC) measured in CBCT image sections and PA were compared, and the buccal bone level was determined in the CBCT images. Results Two Ea and one De implants failed to osseointegrate. Forty-nine patients attended the 10-year control and due to poor quality of 5 CBCT scans, useful CBCT images were available from 44 patients (Ea:12, De:17, La:15). No significant differences between CBCT and PA images in measurements of the interproximal bone levels were observed. Ten years after implant placement, BIC at the buccal aspect was located on average 2 mm apically to the implant platform (2.39 ± 1.06 mm [median = 2.36] for Ea, 2.22 ± 0.99 mm [median = 2.16] for De, and 1.85 ± 0.65 mm [median = 1.95] for La implants) with no significant difference among the groups ( P = 0.20). Mean buccal bone level ( bBL) for implants with an intrabony or a dehiscence defect at second stage surgery was 2.51 ± 1.12 mm [median = 2.70] and 2.84 ± 0.70 mm [median = 2.79], respectively, while 1.78 ± 0.74 mm [median = 1.93] for the implants with no defect. The difference in bBL between the implants without a defect and those with a dehiscence was significant at 10 years ( P = 0.0005). Conclusion Time of placement of single-tooth implants after tooth extraction did not significantly influence the peri-implant buccal bone level, while presence of a buccal bone dehiscence at second stage surgery resulted in significantly more apically located BIC buccally at 10 years. [ABSTRACT FROM AUTHOR]

Aim To present the10-year esthetic outcome data for single-tooth implants placed early or delayed after tooth extraction. Material and Methods Forty-four patients randomly allocated to two equal size groups were treated with a single-tooth implant approximately 10 days ( Ea; N = 22), or 3 months ( De; N = 22) after tooth extraction. Healing abutments were mounted after 3 months of submerged healing, and metal-ceramic crowns cemented after one additional month. Presence of buccal bone defects was registered at the second-stage surgery. Patients attended control visits 1 week and 1-1.5 years after mounting of the crown and 5 and 10 years after implant placement. Marginal bone level at the implant and the adjacent teeth as well as the distance between the implant and the teeth were measured in standardized periapical radiographs. The papilla dimension and clinical crown height ( CCH) were assessed on clinical photographs by an experienced prosthodontist. Results Two Ea and one De implants failed to osseointegrate. Twenty-eight patients (13 Ea and 15 De) who attended all four control visits were included in the data analysis. Complete papilla fill interproximally was achieved in one-third of the cases and an appropriate clinical crown height in <60% after 10 years. Although not statistically significant, early-placed implants tended to be superior to delayed-placed implants regarding soft tissue appearance just after crown delivery and after 10 years. An improvement in papilla dimensions was seen during the follow-up period for both groups while the CCH was unchanged. The implant region (anterior vs. posterior) did not significantly influence the papilla or CCH scores while younger patients (<50 years of age) received significantly better papilla scores than older patients (≥50 years). An apically located bone level at the tooth neighboring the implant influenced negatively the papilla dimension. In contrast, the presence of a bone defect buccally to the implant at second-stage surgery did not have a negative impact on the CCH 10 years after implant placement. Conclusion Early placement of single-tooth implants after tooth extraction performed equally to delayed placement in regard to the esthetic outcome of the soft tissues after 10 years in function. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to present the 10-year clinical and radiographic data from a RCT on single-tooth implants placed early, delayed, or late after tooth extraction. Materials and Methods Sixty-three patients were randomly allocated to three groups and received an implant on average 10 days ( Ea), 3 months ( De), or 17 months ( La) after tooth extraction. Second-stage surgery was performed after 3 months of submerged healing; metal-ceramic crowns were cemented after one additional month. Standardized periapical radiographs were taken 1 week after implant placement ( TP), 1 week ( TC) and 1-1.5 year ( T1) after crown delivery, and 10 years after implant placement ( T10). Pocket depth ( PD) and bleeding on probing were registered during controls ( TC - T10). Results Two Ea and one De implants failed to osseointegrate. Seven patients (4 Ea, 1 De, and 2 La) were not available at T10. No significant differences were found among groups regarding implant survival or radiographic peri-implant marginal bone levels (Ea: 1.15 ± 0.77; De: 1.53 ± 1.06; La: 1.42 ± 1.07) at T10. Similarly, no differences were observed among groups in the number of implants with PD ≥5 mm (Ea: 29%; De: 35%; La: 44%) or the average depth of the sites with PD ≥5 mm (Ea: 5.4 ± 0.7; De: 6.1 ± 1.4; La: 5.4 ± 0.5) at T10. Peri-implant mucositis was found in 70% of the cases; peri-implantitis was diagnosed only in two implants (1 De, 1 La) corresponding to 4.3%. Conclusion Single-tooth implants placed early or delayed after tooth extraction show high survival rates and limited peri-implant marginal bone resorption or biological complications, similar to what is observed with implants placed according to the conventional (late) protocol. [ABSTRACT FROM AUTHOR]

Background and aim In cases with limited bone height, short implants could be a good alternative to augmentation procedures. The aim of this randomized controlled trial was to compare the clinical performance of implants of 6 mm or 11 mm in length in the posterior region. Materials and methods In this multicenter trial (six study sites), 95 subjects were included. Subjects were randomly allocated to receiving implants with lengths of either 6 or 11 mm both with a diameter of 4 mm ( Osseo Speed™ 4.0 S; Astra Tech AB; Mölndal, Sweden). In all cases, there had to be sufficient bone height to allow placement of an implant of at least 11 mm in length. Two or three implants were placed per subject using one-stage surgery with a 42-48 days' healing period before loading. They were restored with a screw-retained splinted fixed prosthesis. Clinical and radiographic examinations were performed preoperatively, postsurgery, at loading, and 6 and 12 months after prosthesis placement. Results A total of 208 implants were inserted in 49 subjects receiving 6-mm implants (test) and in 46 subjects receiving 11 mm implants (control). Two 6-mm implants failed before loading and one 6 and 11 mm implants failed before 1-year evaluation. From loading to the 12 months' follow-up, a mean marginal bone gain of 0.06 mm in the 6 mm group and 0.02 mm in the 11 mm group was found ( P = 0.478). Soft tissue behavior was equal in both groups (Bleeding and plaque [ P = 1.0] probing depth [ P = 0.91]). Conclusion One-year data indicate that treatment with the 6 mm implants is as reliable as treatment with the 11 mm implants. This provides a good treatment option in situations with limited bone height in the premolar and molar regions. Whether or not short implants provide a predictable treatment alternative to bone augmentation procedures remains to be investigated in the future randomized controlled clinical trials. [ABSTRACT FROM AUTHOR]