Randomized controlled multi-centre study comparing shorter dental implants (6 mm) to longer dental implants (11-15 mm) in combination with sinus floor elevation procedures: 10-year data.

AIM: To compare implant survival and complication rates between shorter and standard-length implants with sinus augmentation and restored with single crowns, at 10 years of loading. MATERIALS AND METHODS: One-hundred and one patients (137 implants) with a ridge height of 5-7 mm in the posterior maxilla were randomly assigned to two treatment modalities: shorter implants (6 mm) (group short [GS]) or standard-length implants (11-15 mm) with sinus grafting (group graft [GG]). Following the insertion of final restorations, patients were regularly recalled for up to 10 years. Assessed outcomes encompassed implant survival, marginal bone levels (MBLs), biological and technical parameters and patient-reported outcome measures (OHIP-49 = Oral Health Impact Profile). Non-parametric statistical analysis was used to analyse the data. RESULTS: For the 5- to 10-year follow-up period, 77 patients with 105 implants (GS: 36 patients/48 implants; GG: 41/57) were available for re-examination (drop-out rate 21%). Implant survival rates at the patient level were 96.0% (GS; 2 failures) and 100% (GG) (inter-group p = .24). Median MBLs amounted to 0.00 mm (min 0.00; max 3.25; GS) and 0.00 mm (min 0.00; max 4.55; GG) (inter-group p = .73). Technical complications predominantly occurred within the first 5 years (inter-group p > .05). Peri-implantitis rates were 4.2% (GS) and 13.3% (GG) (intergroup p = .37). Median OHIP-49 scores were 7.00 (0.00; 39.00; GS) and 9.00 (0.00; 196; GG) (inter-group p = .61) at 10 years. CONCLUSIONS: Based on similar 10-year implant survival rates, reduced patient morbidity and lower costs, the use of shorter dental implants might well serve as an alternative treatment concept to longer implants placed in conjunction with sinus grafting for patients with a limited ridge height in the posterior maxilla. Study register: https://clinicaltrials.gov/ct2/show/NCT01030523.

Single immediate implant placement in the maxillary aesthetic zone with and without connective tissue grafting: Results of a 5-year randomized controlled trial.

AIM: To assess the 5-year effects of grafting connective tissue while undertaking single immediate implant placement and provisionalization at the mid-buccal mucosa level (MBML). Secondary outcomes were buccal bone wall thickness (BBT), marginal bone level (MBL) and patient satisfaction. MATERIALS AND METHODS: Sixty patients with a single failing tooth in the maxillary anterior region were provided with an immediately placed and provisionalized implant. At implant placement, the patients randomly received either a connective tissue graft from the maxillary tuberosity (n = 30, test group) or no graft (n = 30, control group). The alveolar socket classification was mainly Type 2A. Data were collected before removing the failing tooth (T0 ), and at 1 (T1 ), 12 (T12 ) and 60 (T60 ) months after final crown placement. The primary outcome was the change in MBML compared with the pre-operative situation. Additionally, the change in BBT, MBL, aesthetics (using the Pink Aesthetic Score-White Aesthetic Score), soft-tissue peri-implant parameters and patient satisfaction were assessed. RESULTS: At the 5-year follow-up, 27 patients could be analysed from each group. In each group, one implant was lost during the osseointegration period, within 3 months of placement, resulting in an implant survival rate of 96.7% in both groups. MBML change at T60 was -0.6 (-1.1 to -0.1) mm in the control group and 0.1 (-0.4 to 0.5) mm in the test group (p = .008). BBT and MBL, aesthetics, soft-tissue peri-implant parameters and patient satisfaction showed stable results and satisfied patients, without clinically relevant differences between the groups. CONCLUSIONS: This 5-year follow-up study shows that grafting connective tissue when replacing a single failing tooth with immediately placed and provisionalized implant results in favourable peri-implant tissues and fewer MBML changes.

Immediate implant placement with immediate or delayed provisionalization in the maxillary aesthetic zone: A 10-year randomized trial.

AIM: To compare the marginal bone level of immediately placed implants, with either immediate or delayed provisionalization (IP or DP), in the maxillary aesthetic zone after 10 years of function. MATERIALS AND METHODS: Participants with a failing tooth in the maxillary aesthetic zone were randomly assigned to immediate implant placement with either IP (n = 20) or DP (n = 20) after primary wound closure with a free gingival graft. The final restoration was placed 3 months after provisionalization. The primary outcome was change in marginal bone level. In addition, implant survival, restoration survival and success, peri-implant tissue health, mucosa levels, aesthetic indices, buccal bone thickness and patient satisfaction were evaluated. RESULTS: After 10 years, the mean mesial and distal changes in marginal bone level were -0.47 ± 0.45 mm and -0.49 ± 0.52 mm in the IP group and -0.58 ± 0.76 mm and -0.41 ± 0.72 mm in the DP group (p = .61; p = .71). The survival rate was 100% for the implants; for the restorations, it was 88.9% in the IP group and 87.5% in the DP group. Restoration success, according to modified USPHS criteria, was 77.8% in the IP group and 75.0% in the DP group. The prevalence of peri-implant mucositis was 38.9% and 35.7% and of peri-implantitis 0.0% and 6.3%, respectively, in the IP group and DP group (p = 1.0; p = .40). The Pink Esthetic Score and White Esthetic Score was 15.28 ± 2.32 in the IP group and 14.64 ± 2.74 in the DP group, both clinically acceptable (p = .48). The buccal bone thickness was lower in the DP group. Patient satisfaction was similar in both groups (p = .75). CONCLUSIONS: The mean marginal bone level changes after immediate implant placement with IP were similar to those after immediate placement with DP. CLINICAL TRIAL REGISTRATION: Registered in the National Trial Register (NL9340).

Clinical outcomes and risk factor analysis of dental implants inserted with lateral maxillary sinus floor augmentation: A 3- to 8-year retrospective study.

AIM: To evaluate the 3- to 8-year outcomes of dental implants placed with lateral sinus floor augmentation (LSFA) and to identify factors affecting implant survival. MATERIALS AND METHODS: This retrospective study was performed by screening all implants placed with LSFA procedures, which were conducted between January 2012 and December 2016. Subantral bone gain (SABG) and apical bone height (ABH) were assessed using panoramic radiographs. The cumulative survival rate of implants was analysed using life-table analysis and Kaplan-Meier survival curves. The influential risk factors affecting survival were assessed using univariate log-rank tests and multivariable mixture cure rate model. Implant complications were recorded. RESULTS: Based on the established criteria, a total of 449 patients (760 implants) were included in this study. In the 3- to 8-year follow-up (mean ± SD, 5.81 ± 1.33 years), 15 implants in 14 patients failed, with a CRS of 96.81% on an implant basis and 95.07% on a patient basis. A history of periodontitis and poor compliance with supportive periodontal treatment was associated with a significantly higher risk of implant failure at both implant and patient levels. Significant decreases in ABH occurred during each yearly interval except for 3 years. A similar trend has been observed for SABG at 1, 2, 6 and 8 years. The total complication rate was 31.84% on implant basis, with peri-implant mucositis (21.58%) being the most frequent biologic complication and porcelain cracking (5.00%) being the most common technical complication. CONCLUSIONS: Implant with LSFA is a reliable treatment option in atrophic maxilla. A history of periodontitis without regular supportive periodontal treatment was identified as a predictor for implant failure. Slight but significant shrinkage of vertically augmented bone can be observed after implant placement.

A Randomized Controlled Trial on the Timing of Soft-Tissue Augmentation in Immediate Implant Placement: Hard-Tissue Changes and Clinical Outcome.

AIM: To assess the impact of the timing of soft-tissue augmentation (STA) on mean buccal bone changes following immediate implant placement (IPP) in the anterior maxilla. MATERIALS AND METHODS: Patients with a failing tooth and intact buccal bone wall in the anterior maxilla (15-25) were enrolled in this randomized controlled trial. Following single IIP and socket grafting, they were randomly allocated to the control group (immediate STA performed during the same surgical procedure) or the test group (delayed STA performed 3 months later). Implants were placed with a surgical guide and immediately restored with an implant-supported provisional crown. Changes in bone dimensions were assessed using superimposed CBCT images taken prior to surgery and at 1-year follow-up. Clinical outcomes were registered at 1-year follow-up. RESULTS: Twenty patients were randomized to each group (control: 16 females, 4 males, mean age 57.6; test: 9 females, 11 males, mean age 54.2). Ten patients in the control group and 13 patients in the test group had a thick bone wall phenotype. Estimated marginal mean horizontal buccal bone loss at 1 mm below the implant shoulder was -0.553 and -0.898 mm for the control and test group, respectively. The estimated mean difference of 0.344 mm in favour of the control group was not significant (95% CI: -0.415 to 1.104; p = 0.363). Also at all other horizontal and vertical levels, no significant differences could be observed between the groups. The combination of socket grafting and STA enabled counteraction of any buccal soft-tissue loss (≥ 0 mm) at 1 mm below the implant shoulder in 82% of the patients in the control group and in 75% of the patients in the test group (p = 1.000). The clinical outcome was favourable in both groups, yet implants in the control group demonstrated slightly less marginal bone loss (median difference 0.20 mm; 95% CI: 0.00-0.44; p = 0.028). CONCLUSION: In patients with an intact and mainly thick buccal bone wall in the anterior maxilla, the timing of STA following IIP had no significant impact on mean buccal bone loss. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05537545.

Single crowns in the posterior maxilla supported by either 11-mm long implants with sinus floor augmentation or by 6-mm long implants: A 10-year randomized controlled trial.

OBJECTIVES: To compare the clinical performance of single crowns in the posterior maxilla supported by either 11-mm long implants combined with maxillary sinus floor augmentation (MSFA) surgery or by 6-mm long implants during a 10-year follow-up period. MATERIALS AND METHODS: Subjects were randomly allocated to receive one 11-mm long implant in combination MFSA or to receive one 6-mm long implant without any grafting. Twenty-one implants in 20 patients were placed in the 6-mm group and 20 implants in 18 patients were placed in the 11-mm group. Both groups were followed by clinical and radiographic examinations up to 10 years. Patients' satisfaction was also scored before treatment. RESULTS: Two patients died and eight patients moved during the follow-up. Two patients lost an implant in the 6-mm group and one implant was lost in the 11-mm group (implant survival 89.5% and 90.9%, respectively). From loading to 10 years' follow-up, mean ± SE marginal bone loss in the 6-mm group and 11-mm group was 0.18 ± 0.10 mm and 0.26 ± 0.12 mm, respectively, without a significant difference between the groups at 10 years (p = .650). In both groups, indices scores for plaque, calculus, gingiva and bleeding were low as well as mean pocket probing depth. Patients' satisfaction at 10 years was high in both groups; mean overall satisfaction in the 6-mm group and 11-mm group was 9.6 ± 0.6 and 9.2 ± 0.8, respectively (p = .168). CONCLUSIONS: Placement of 6-mm implants or 11-mm implants combined MFSA are equally successful during a 10-year follow-up period when applied for supporting a single restoration.

Effect of intraoral administration of parathyroid hormone on osseous and soft tissue healing around implants in ovariectomized rat maxillae.

OBJECTIVES: Intermittent administration of parathyroid hormone (PTH) increases systemic bone mass. However, the effect of PTH on osseous and soft tissue healing around implants in osteoporosis patients remains unclear. This study aimed to investigate the effects of PTH on tissue healing around implants in ovariectomized rats and to compare systemic and intraoral administration routes. MATERIAL AND METHODS: Implants were placed at the healed sites of ovariectomized rats 3 weeks after maxillary first molar extraction. Rats were randomly divided into two groups that received either daily systemic subcutaneous or local intraoral PTH administration. Maxillae were dissected to examine bone architectures with micro-computed tomography images. Histomorphometric and immunohistochemical analyses were performed to evaluate osseous and soft tissue healing around the implants. RESULTS: Regardless of the administration route, PTH significantly increased bone area and the numbers of osteoblasts, osteoclasts, and osteocytes in the first and second inside and outside areas of implant threads, in addition to decreasing the number of sclerostin+ osteocytes. However, the intraoral PTH administration route was superior to the systemic route by significantly improving bone quality and promoting collagen production in the connective tissue around implants. CONCLUSIONS: Parathyroid hormone administration promoted both osseous and soft tissue healing around implants, irrespective of administration route. Interestingly, intraoral administration improved the evaluated parameters more than systemic administration. Thus, the intraoral route could become a useful treatment strategy for implant treatment in osteoporosis patients.

Factors influencing speech improvement following maxillary complete-arch implant-supported restorations: A retrospective study.

OBJECTIVE: This study explored factors affecting speech improvement in patients with an edentulous maxilla after the delivery of a complete-arch implant-supported fixed dental prosthesis (IFDP). MATERIALS AND METHODS: Patients who had received IFDP for edentulous maxilla were enrolled, and various potential speech improvement-related factors were considered, including patient demographics, anterior residual bone volume, preoperative facial features, preoperative acoustic parameters, and adaptation time. Acoustic analysis and perceptual ratings were used to assess three fricatives [s], [f], and [ɕ]. Correlation and regression analyses were conducted to assess the association between changes in fricatives and potential factors (α = .05). RESULTS: The study included 50 patients (18 females and 32 males, aged 50.62 ± 15.71 years, range 19-76). Significant correlations were found among the change in the center of gravity (ΔCoG) of [s] and anterior residual bone volume, zygomatic implants number and proportion (p < .05). These correlations were largely mirrored in the perceptual score (ΔPS) changes. After controlling for age, sex, preoperative acoustic parameters, and adaptation time, the ΔCoG and ΔPS of fricatives were mainly correlated with the anterior residual bone volume, preoperative acoustic parameters, and adaptation time. CONCLUSION: Speech improvements post-IFDP delivery are mainly related to preoperative speech characteristics, anterior residual bone volume, and adaptation time. The residual bone volume's impact on consonants varies with specific articulatory gestures. This study provides insights into forecasting speech outcomes following IFDP restoration and provides recommendations and methods for data collection in developing future prediction models.

Single-piece zirconia versus single-piece titanium, narrow-diameter dental implants in the anterior maxilla: 5-year post-loading results of a randomized clinical trial.

OBJECTIVES: The aim of this study was to evaluate esthetic parameters in the anterior maxillary region by comparing single-piece zirconia versus titanium narrow-diameter implants. Additionally, clinical, radiological and patient-reported outcome measures (PROMs) were analyzed. MATERIALS AND METHODS: Thirty implants (tissue level implant) were placed in 30 patients in the maxillary esthetic sector. Depending on randomization, a zirconia (test) or titanium implant (control) was placed. Esthetic, clinical, and radiological parameters, including the implant crown esthetic index (ICAI), pink esthetic score (PES), probing pocket depth, bleeding on probing, plaque index, and marginal bone levels, were evaluated at 12, 36 and 60 months after loading. RESULTS: Sixty months after crown placement, no significant differences were found between groups. The ICAI values were 5.25 ± 4.21 and 4.50 ± 2.98 for the test and control groups, respectively. The corresponding PES values were 7.44 ± 1.93 and 7.43 ± 1.74 for the test and control groups, respectively. There were no significant intergroup differences for the rest of the parameters evaluated. CONCLUSION: It can be suggested that monotype zirconia implants may serve as a potential alternative to titanium implants in selected clinical scenarios. While the results demonstrated comparable esthetic, clinical, and radiological aspects for zirconia implants as compared to titanium implants after a 5-year follow-up period, further research with larger sample sizes and longer-term follow-up is recommended.

Effects of hard- and/or soft-tissue grafting with early implant placement: Histomorphometric outcomes of an exploratory study in canines.

OBJECTIVE: To histomorphometrically determine the effects of hard- and/or soft-tissue augmentation by applying the early implant placement protocol. MATERIALS AND METHODS: The distal roots of the maxillary second and third premolars were extracted in 10 mongrel dogs. After 1 month, early implant placement was performed in the distal roots, resulting in buccal dehiscence defects. Four treatments were then randomly applied: (1) guided bone regeneration (GBR), (2) connective tissue grafting (CTG), (3) simultaneous GBR and CTG (GBR + CTG) and (4) no further treatment (control). Healing abutments were connected to all implants to allow non-submerged healing. At 4 and 16 weeks, tissue sections were harvested and histomorphometric analyses were performed. RESULTS: Group GBR presented the largest total tissue thickness at 4 weeks, but underwent a greater remodelling compared with the other groups between 4 and 16 weeks. At 16 weeks, the overall tissue thickness was largest in group GBR + CTG. This group was also the most favourable in terms of the level of the margo mucosae and the presence of mineralized tissue at the coronal level. Group CTG demonstrated a stable tissue thickness over time, with a larger thickness at 16 weeks compared with group GBR. CONCLUSION: Simultaneous CTG and GBR resulted in the most-favourable tissue thickness when applying the early implant placement protocol.

A randomized clinical trial on zirconia versus titanium implants in maxillary single tooth replacement.

OBJECTIVES: This RCT aimed to compare zirconia and titanium dental implants in the maxillary premolar region. The comparison was based on marginal bone level (MBL) changes, clinical parameters, aesthetic outcomes, and patient related outcome measures (PROMs) 1 year after prosthetic loading. MATERIALS AND METHODS: Fifty patients were randomly assigned to receive either a zirconia (ZrO2, n = 25) implant or a titanium (Ti, n = 25) bone-level implant. Implants were provided with a lithium disilicate crown 3 months after placement. Follow-up was at 1 month and after 1 year. The primary outcome pertained to changes in MBL. Reported secondary outcomes consisted of implant survival, peri-implant tissue health, aesthetics, and PROMs. RESULTS: Mean MBL change after 1 year was 0.01 mm (SD = 0.45; min = 0.72, max = 0.86) for ZrO2 and -0.09 mm (SD = 0.34; min = 0.53, max = -1.06) for Ti (p = .439). Scores for the other clinical outcome parameters and PROMs were generally favorable, with no significant differences. However, significant differences were found for the aesthetic outcomes regarding two criteria: (a) level of facial mucosa (p = .022), in favor of Ti, and (b) root convexity/soft tissue color and texture (p = .005) in favor of ZrO2. CONCLUSION AND CLINICAL IMPLICATIONS: The ZrO2 and Ti implant types used in this study, replacing a single missing maxillary premolar, show a comparable outcome in terms of MBL change after 1 year. Clinical and aesthetic parameters, as well as PROMs, are favorable and similar between both implant types after 1 year of prosthetic loading. These short-term study results suggest that both are suitable for clinical use.

Maxillary bone augmentation with calvarial bone graft for immediate full-arch rehabilitation: Insights from a 10-year proof-of-concept retrospective analysis.

OBJECTIVE: Evaluate the long-term outcomes of full-arch rehabilitation using immediate dental implant placement and continuous functional loading with full-fixed dental prostheses (FFDPs). MATERIALS AND METHODS: Fifty-six patients received temporary implants (n = 327) at maxillary augmentation with calvarial bone. A provisional acrylic FFDP was immediately loaded onto these implants. After 6 months, the temporary implants were replaced with definitive implants (n = 326) and immediately loaded with a second provisional FFDP (N = 55). Subsequently, a baseline radiograph was taken following a 6-month healing period. The second bridge was then substituted with a definitive FFDP. Primary outcomes included peri-implant marginal bone level (MBL) and definitive implant survival. Secondary outcomes evaluated provisional implant and prostheses survival, complications, and patient satisfaction. RESULTS: The provisional implants had a survival rate of 97.9%. One patient was excluded from further analysis due to loss of temporary implants and first FFDP. The definitive implant survival rate after 10 years was 92.2%, with a moderate but significant decrease in MBL between baseline radiography and 10 years later (-0.08 ± 0.18 vs. -0.24 ± 0.44). However, large individual variations were observed, with 65.8% of implants showing no bone loss and 9.2% showing loss ≥0.5 mm. Sinusitis was experienced by 14.3% of patients upon surgery. Patient satisfaction was high or reported no issues after protocol completion (80%). One patient lost all six definitive implants and definitive FFDP 8.2 years after implant placement. CONCLUSIONS: The described protocol can be regarded as a long-term, highly successful method for full-arch rehabilitation of atrophied maxillae while enabling continuous masticatory and speaking functionality.

Hard and soft tissue alterations using dual-zone concept versus connective tissue graft at maxillary immediate implant placement: A 1-year randomized clinical and volumetric trial.

OBJECTIVES: To evaluate the esthetic outcome, as well as clinical, radiographic, and volumetric tissue alterations 1 year after immediate implant placement (IIP) with connective tissue grafting (CTG) versus dual-zone concept (DZ) at sites with thin labial bone in the esthetic zone. MATERIALS AND METHODS: This randomized clinical trial included 30 patients treated with IIP simultaneous with either CTG or DZ (n = 15 each). Pink esthetic score (PES) was assessed 6 months after crown placement as the primary outcome. Amount of bone labial to the implant, labio-palatal ridge reduction, and crestal bone changes were measured via CBCT after 1 year. Volumetric analysis of linear labial soft tissue contour, interdental, and mid-facial soft tissue level changes, and total volume loss (mm3) were measured after 1 year. RESULTS: Similar PES was observed in the CTG (12.53 ± 1.13) and DZ (12.13 ± 1.55) groups, with no significant difference (p = 0.42). Likewise, there were no statistically significant differences found between the two groups in labio-palatal bone reduction (mm&%), interdental papillae, and mid-facial gingival levels (p > 0.05). However, the mean vertical crestal bone changes in the CTG and DZ groups were -1.1 ± 0.6 mm and 0.2 ± 1.0 mm, respectively, with a statistically significant difference (p = 0.0002). Moreover, CTG revealed less linear and total volume (mm3) loss in the labial soft tissue which was statistically significant compared to DZ (p = 0.007). CONCLUSION: Both groups demonstrated the same PES, nevertheless, volumetric analysis revealed twice total labial volume loss in DZ compared to CTG. It might be concluded that the use of CTG with IIP caused less horizontal reduction in the supra-implant complex compared to the DZ.

Histological and radiological outcome after horizontal guided bone regeneration with bovine bone mineral alone or in combination with bone in edentulous atrophic maxilla: A randomized controlled trial.

OBJECTIVE: To assess the radiological and histological outcome after horizontal guided bone regeneration (GBR) with deproteinized bovine bone mineral (DBBM) alone or in combination with particulate autogenous bone (PAB). MATERIALS AND METHODS: Eighteen edentulous patients with an alveolar ridge of ≤4 mm were included in this split-mouth randomized controlled trial. Horizontal GBR with a graft composition of 100% DBBM (100:0) on one side and 90% DBBM and 10% PAB (90:10) on the other side were conducted in all patients. Cone beam computed tomography (CBCT) was obtained preoperatively, immediately postoperative, and after 10 months of healing. Width and volumetric changes in the alveolar process were measured on CBCT. Implants were placed after 10 months of graft healing where biopsies were obtained for histomorphometrical evaluation. RESULTS: The gained widths were 4.9 (±2.4) mm (100:0) and 4.5 (±2.0) mm (90:10) at 3 mm from the top of the crest, and 5.6 (±1.3) mm (100:0) and 4.6 (±2.1) mm (90:10) at 6 mm from the top of the crest. The mean volumetric reductions were 32.8% (±23.8) (100:0) and 38.2% (±23.2) (90:10). Histomorphometry revealed that mean percentages of bone were 50.8% (±10.7) (100:0) and 46.4% (±11.3) (90:10), DBBM were 31.6% (±12.6) (100:0) and 35.4% (±14.8) (90:10), and non-mineralized tissue were 17.6% (±11.7; 100:0) and 18.2% (±18.2) (90:10). No significant differences were evident between in any evaluated parameters. CONCLUSIONS: There were no additional effects of adding PAB to DBBM regarding bone formation, width changes, or volumetric changes after 10 months of graft healing.

Accuracy of open-sleeved vs. closed-sleeved static computer-assisted implant systems in immediate maxillary molar implant placement: An in vitro study.

OBJECTIVES: The objective of this study is (1) to compare the accuracy of an open-sleeved static computer-assisted implant system (sCAIS) with a closed-sleeve sCAIS and free-hand approach in immediate implant placement (IIP) of maxillary molar sites and (2) to investigate the influence of socket morphology on these approaches. MATERIALS AND METHODS: Ninety partially edentulous duplicated maxillary models simulating three different molar sockets (type A, B, and C based on Smith and Tarnow's classification) were investigated. Three modalities, including sCAIS with open-sleeves, sCAIS with closed-sleeves, and free-hand approach, were applied separately to 30 models with 120 sockets. A customized Python script automatically measured the deviations between the virtual and actual implant positions for all 360 implants. RESULTS: The 3D deviations of sCAIS were significantly influenced by the socket and sleeve types. Both guided groups exhibited significantly less deviation than the free-hand approach. Type A and C sockets resulted in better implant positions than type B socket sites. In type B sockets, the open-sleeve group achieved significantly less deviation compared to the closed-sleeve group, with respect to apical global (1.34 ± 0.53 vs. 1.84 ± 0.59 mm), coronal horizontal (0.68 ± 0.36 vs. 0.93 ± 0.34 mm), apical horizontal (1.21 ± 0.59 vs. 1.74 ± 0.63 mm), and angular (3.30 ± 1.41 vs. 4.41 ± 1.96°) deviations. CONCLUSIONS: Guided implant surgery significantly reduces deviations during molar IIP compared to free-hand procedures. Furthermore, the use of open-sleeve sCAIS appears to be more effective in minimizing deviations in type B sockets when compared with the closed-sleeve guided system.

Maxillary and mandibular overdentures retained by two unsplinted narrow-diameter titanium-zirconium implants - A clinical pilot study.

OBJECTIVES: To evaluate the survival rates and marginal bone loss of narrow-diameter titanium-zirconium implants supporting complete maxillary and mandibular overdentures up to 3 years after loading. MATERIALS AND METHODS: Ten completely edentulous patients who were dissatisfied with their complete dentures were enrolled. Two narrow-diameter implants were placed in the canine region of the maxilla and mandible. After second-stage surgery, implant-supported overdentures (palatal-free) attached by parallel alignable stud-attachments were placed. Patients were followed periodically for up to 36 months. Standardized radiographs were taken at baseline, 12 and 36 months to analyze mean marginal bone level changes around the implants. RESULTS: The Kaplan-Meier survival rates were 100% for mandibular and 68.0% (SE ± 10.9%) for maxillary implants at 36 months (p = .008). Six maxillary implants failed after loading; no mandibular implants were lost. Five implants failed due to loss of osseointegration. One implant fractured. The mean marginal bone level changes around the analyzed implants (n = 28, 9 patients) were -0.71 ± 0.82 mm in the mandible and -2.08 ± 1.52 mm in the maxilla at the 36-month follow-up. The difference in marginal bone level changes between the maxilla and mandible was significant (p = .019) at the 12- and 36-month follow-ups. CONCLUSION: Two narrow-diameter titanium-zirconium implants with stud-attachments showed a highly satisfactory outcome in the mandible. The maxillary implants showed a high failure rate and significantly more bone loss over time than the mandibular implants. The minimal concept of two implants and an overdenture should be limited to the edentulous mandible.

The influence of bone block graft position on bone dimensional changes in staged onlay horizontal ridge augmentation: A 6-month retrospective cohort study.

OBJECTIVES: To analyze changes in bone dimensions and their modulating factor in bone dimensions 6 months after horizontal ridge augmentation using autogenous bone grafts. MATERIALS AND METHODS: Thirty-eight patients with horizontally atrophic alveolar ridges of a single edentulous tooth at the maxillary anterior site were divided into two groups based on the fixation position of the bone block during ridge augmentation surgery (H0, vertical distance from the upper edge of the bone block to the alveolar crest). Patients were classified into a crestal level (CL) group if H0 ≤ 1 mm and a sub-crestal level (SCL) group if H0 > 1 mm. The width and height of the alveolar ridge were recorded using CBCT both before and 6 months after the augmentation procedure. RESULTS: The CL group comprised 20 patients with 23 implants, whereas the SCL group comprised 18 patients with 22 implants. All the augmentation sites exhibited vertical bone resorption. Vertical bone resorption in the SCL group (1.94 ± 2.11 mm) was significantly higher than that of the CL group (0.61 ± 0.64 mm). The SCL group showed significantly lower horizontal bone gain than the CL group (SCL: 1.02 ± 2.30 mm; CL: 3.19 ± 3.17 mm) at the cervical level. Peri-implant marginal bone loss increased significantly in the SCL group (1.00 ± 2.71 mm) compared to the CL group (0.64 ± 0.40 mm). CONCLUSION: The bone height decreased after horizontal ridge augmentation using autogenous onlay grafting. The fixation position of the bone block was a modulating factor. The SCL group showed more vertical bone loss, less horizontal bone gain 6 months after surgery, and more marginal bone loss after restoration.

Effects of SARPE and MISMARPE on correction of transverse maxillary deficiency: A preliminary comparative evaluation.

AIM: The present study was designed to compare, on cone-beam computed tomography imaging, the skeletal and dental effects of the SARPE (Surgically assisted rapid palatal expansion) and MISMARPE (Minimally Invasive Surgical and Miniscrew-Assisted Rapid Palatal Expansion) techniques. MATERIALS AND METHODS: The sample of adult patients with transverse maxillary deficiency (TMD) was divided into two groups, and scans were obtained preoperatively (T0) and immediately after completion of expansion (T1). The posterior and anterior linear transverse distances of the maxilla and the angulation of the maxillary first molars were evaluated. The data were entered into a generalized estimating equations model to verify the postoperative effects of the different techniques. RESULTS: None of the techniques caused any appreciable change in the angulation of the molars. The skeletal changes were similar, with significantly greater gains in the nasal fossa and intermaxillary distance when using the MISMARPE. CONCLUSION: The technique can be an effective and lower morbidity alternative to SARPE.

A comparison of maxillary posterior changes following facemask therapy: Skeletal anchorage versus tooth-borne anchorage.

OBJECTIVE: To compare changes in the maxillary posterior structure as seen in cone-beam computed tomography (CBCT) images resulting from facemask therapy using skeletal (miniplate/FM) anchorage versus tooth-borne anchorage (RME/FM). MATERIALS AND METHODS: A retrospective study was conducted on 20 patients divided into the miniplate/FM group (nine patients aged 9.5 ± 1.4 years) and the RME/FM group (11 patients aged 9.2 ± 1.4 years). CBCT images before and after facemask therapy were evaluated to assess changes in the maxillary posterior structure. RESULTS: The miniplate/FM group had greater advancement of the maxilla and midface compared to the RME/FM group (p < .05). Specifically, there was about three times more advancement of the pterygomaxillary suture in the miniplate/FM group than in the RME/FM group (p < .05). Moreover, the advancement of the pterygomaxillary suture was about half the advancement of A point in the miniplate/FM group, while only about 25% in the RME/FM group. Finally, the miniplate/FM group showed an increase in the transverse dimension of the posterior and superior parts of the maxilla (p < .05). CONCLUSION: There was greater forward movement of the pterygomaxillary suture with facemask therapy using the skeletal anchorage compared to tooth-borne anchorage, leading to a more significant advancement of the maxilla and midface.

A retrospective study of alveolar bone remodelling after anterior retraction in orthodontic tooth extraction cases with clear aligners and fixed appliances.

OBJECTIVES: To evaluate alveolar bone dimensions and its relationship with tooth movement (retraction, intrusion and torque) during orthodontic treatment with fixed appliance and clear aligners. METHODS: Thirty-two patients were included in this retrospective clinical study. Cone beam computed tomography (CBCT) was collected before and after treatment to measure the volume of dehiscence and fenestrations in the maxillary anterior region, anterior alveolar bone thickness and height and degree of tooth movement. Rank-sum tests were used to compare the differences in alveolar bone defect volumes between clear aligners and fixed appliance, multiple linear regression analysis was used for study evaluation, and kappa statistics were used to assess internal consistency and test-retest reliability. RESULTS: Post-operatively, most alveolar bone defects occurred on the labial side. The incidence of bone fenestration was 23.96% in the clear aligner group and 26.18% in the fixed appliance group, which was higher than the incidence of bone dehiscence (5.21%). The labial bone height decreased by 0.272 mm, and the palatal bone height increased by 0.617 mm for every 1 mm downward intrusion of the anterior tooth apex in the fixed appliance group. In the clear aligner group, there was no significant change in the labial bone height, and the palatal bone height decreased by 0.447 mm for every 1 mm of anterior tooth retraction coronally. CONCLUSIONS: In the fixed appliance group, anterior tooth intrusion and retraction may have led to alveolar bone resorption by its compression at the cervical level. This study provides a three-dimensional tooth movement evaluation method by using CBCT.