Difference In Crestal Bone Loss Research Articles

Influence of Platform-Switched Restoration on Bone Resorption in Patients Treated with Wide-Diameter, External-Hex-Connection Dental Implants: A 10-Year Follow-up Study.

Purpose: To investigate and assess the differences in crestal bone loss (CBL) between wide-diameter, external-hexagon-connection implants restored with platform-switching (PS) and platform-matching (PM) restorations with a follow-up of 10 years. Materials and Methods: This study retrospectively analyzed the updated and enlarged dataset of a 5-year prospective clinical study at 10-year follow-up. The data concerns 182 healthy adult subjects treated in a private dental practice who received a single wide-diameter implant with an external hexagon connection in the molar area, restored with either a PS restoration (test) or PM restoration (control). The amount of CBL was radiographically measured at each annual follow-up, as well as after 5 and 10 years of implant loading. In evaluating the association between the two types of abutments and bone loss (including change over time), a linear mixed effects model was run for longitudinal data. Results: Implants connected with PS restorations exhibited significantly lower reduction (0.25 mm) in CBL than those joined to PM restorations (P < .001; 95% CI from 0.22 to 0.29). However, both groups presented a higher increase in bone loss during the first year (0.58 mm in PS and 0.83 mm in PM) and a linear increment thereafter until the 10-year follow-up (0.046 mm/year; P < .001; 95% CI from .042 to .049). Conclusion: Notwithstanding the limitations of this study, it can be concluded that after 10 years of follow-up, the implant with a wide diameter and external-hexagon connection restored with a PS abutment seems to be more effective in reducing bone loss compared with the PM abutment.

A Split-Mouth Study to Assess the Effect of Implant Surface Roughness on Implant Treatment Outcome After 5 Years.

The aim of current split-mouth study was to compare the implant treatment outcomes of hybrid-surface implants (minimally rough implant collar and moderately rough body) with moderately rough implants after 5 years in patients with a bar-supported mandibular overdenture. Fully edentulous patients were enrolled, and each patient received two implants: one moderately rough and one hybrid-surface implant. A total of 18 patients with 36 implants attended the 5-year recall, and the implant survival rate was 100%. The 5-year evaluation showed no significant difference in crestal bone loss or peri-implant health between the hybrid and moderately rough implants.

New approach to expedite the delivery of the final crowns for teeth requiring crown lengthening surgery: a pilot study

BackgroundThe healing period from crown lengthening procedures (CLPs) often delays the final crown delivery. This study aimed to explore the feasibility of a new approach expediting the delivery of the final crowns for teeth requiring CLPs.MethodsTeeth requiring CLPs and single-crown restorations between the canine and the second molar were included. After the initial tooth preparation, a CLP was performed. In the experimental group, the final tooth preparation and final impression were made during the CLP; the final crown was then delivered at the suture-removal appointment. In the control group, the final impression was made 8 weeks after the CLP. The level of gingival margin (GM), pocket depth (PD), and crestal bone levels (CBLs) were compared between the two groups before CLPs (T0), at delivery of the crowns (T1), and at 12 months in function (T2).ResultsTwenty-one lithium-disilicate crowns were delivered to 20 subjects and followed up. The mean interval between the CLPs and the delivery of crowns was 2.5 weeks for the experimental group and 12 weeks for the control group. No significant differences were observed between the two groups in the level of GM, PD, and CBLs at each time point. No significant treatment difference in crestal bone loss was observed between the two groups at T2 (Experimental = -0.11 mm, Control = -0.03 mm; p = 0.67).ConclusionMaking the final tooth preparation and the final impression at the CLP significantly reduced the time between the CLP and the delivery of the final crown and showed comparable clinical outcomes.

Clinical evaluation of narrow-diameter implants versus standard-diameter implants with lateral bone augmentation in posterior jaws: Three-year results of a randomized controlled trial.

The aim of this study was to compare the 3-year clinical outcomes of narrow-diameter implants (NDI) with standard-diameter implants (SDI) in conjunction with lateral bone augmentation in atrophic posterior jaws. Fifty patients were included and randomly assigned into two groups: Patients in Group 1 received NDI (Ø3.5 mm); patients in Group 2 received SDI (Ø4.3 mm) with simultaneous lateral bone augmentation. Implant survival rates, complications, crestal bone loss, peri-implant conditions, treatment cost, and patient satisfaction were compared. Three patients dropped out the follow-up. No implant loss was observed. The difference in technical complication rates between the two groups was 3.8% (95% CI: -13.7% to 21.3%). No significant differences in crestal bone loss were found between two groups at 3-year follow-up (0.55 ± 0.76 vs 0.41 ± 0.41 mm, p=.429). A total of 20.8% (5/24) of NDI were diagnosed with mucositis and 8.3% (2/24) with peri-implantitis. A total of 17.4% (4/23) of SDI showed mucositis and (1/23) 4.3% showed peri-implantitis. The total cumulative cost of treatment per patient in Group 1 (2849.6 USD, 95% CI: 2726.8-2972.4) was significantly lower than that in Group 2 (3581.4 USD, 95% CI, 3460.9-3701.9) over the 3-year follow-up (p < .01). The patient satisfaction rating of operation was significantly higher in Group 1 (85.42 ± 7.41 vs 80.48 ± 7.95, p=.033). NDI yielded favorable implant survival, acceptable technical and biological complications, and high patient satisfaction supporting single crowns in the atrophic posterior region after 3-year follow-up. NDI might be a reasonable alternative in horizontally deficient posterior jaws. Clinicaltrials.gov identifier: ChiCTR1800020426.

Efficacy of adjunct subgingival minocycline delivery for treatment of peri-implantitis in moderate cigarette smokers.

Localized subgingival minocycline hydrochloride (MH) delivery as an adjuvant to with non-surgical mechanical debridement (NSMD) is useful for the treatment of periodontitis; however, there are no trials that have assessed the efficacy of subgingival MH delivery with NSMD for the treatment of peri-implantitis in cigarette-smokers and non-smokers. This randomized controlled trial assessed the efficacy of subgingival MH delivery with NSMD for the treatment of peri-implantitis in cigarette-smokers. Self-reported current cigarette-smokers and non-smokers with peri-implantitis were encompassed. These individuals were subdivided into 2-subgroups. Patients in test- and control groups received NSMD with and without a single delivery of subgingival MH. Modified-gingival-index (mGI), modified-plaque-index (mPI), probing-depth (PD) and crestal-bone-loss (CBL) were measured at baseline and at 6-months' follow-up. Demographic-data was also collected. Level of significance was set at p<0.01. Twenty-four cigarette-smokers and 24 non-smokers with peri-implantitis were included. There was a significant reduction in mPI (p<0.01), mGI (p<0.01), PD (p<0.01) at 6-months among patients with and without type-2 DM in test- and control-groups. There was no significant difference in peri-implant mPI, PD and mGI, patients with and without type-2 diabetes in test- and control-groups at 6-months of follow-up. There was no significant difference in CBL in all patients at 6-months of follow-up. A single application of subgingival MH delivery is as effective as NSMD alone for the treatment of peri-implantitis in cigarette-smokers and non-smokers.

In vivo Comparison of Crestal Bone Heights Following Implant Placement with "Flapless" and "Flap" Techniques in the Sites of Early Loaded Implants.

Purpose:The purpose was to evaluate the difference in crestal bone loss (CBL) around implants with flap and flapless methods followed by early loading.Materials and Methods:Twenty implants were placed in twenty patients – ten using flap and ten using flapless techniques. The difference in CBL was measured on standardized digital periapical radiograph taken at 0 week, 6 weeks, 12 weeks, and 6 months.Results:The present study showed the mean CBL on proximal surfaces when evaluated at intervals of 0 week, 6 weeks, 12 weeks, and 6 months for flapless method was significantly lower than with flap method the values of which were +0.07 mm against +0.26 mm on mesial side and +0.15 mm against +0.33 mm on distal side at 6 months.Conclusion:The flapless approach is a predictable procedure when patient selection and surgical technique are appropriate, and results in lesser CBL.

Split crest technique for implant treatment of agenesis of the upper lateral incisors: results of a randomized pilot histological and clinical study at 24-month follow-up.

Agenesis of lateral incisors, besides the functional issues, represents a great esthetic drawback. The selection of an appropriate treatment is a complex decision, which should consider the stability of the clinical outcomes over time. The aim of the present study was a histological and clinical comparison of two-stage split crest technique (SCT), with bone chips alone or mixed with porcine bone in patients affected by unilateral and bilateral agenesis of the upper lateral incisors. Eleven patients were enrolled, and randomly assigned to receive a treatment with autologous bone chips (group 1) or autologous bone chips mixed 1:1 to porcine-derived xenogenic bone (group 2). After a 2-month healing period, implants were placed and biopsies harvested for histomorphometrical evaluation. Clinical assessment, according to ICOI PISA health scale, and radiographic marginal bone loss evaluation at 12- and 24-month follow-ups were conducted. The histomorphometry showed significantly greater new bone formation (p > 0.0229) in group 2. At 12- and 24-month follow-ups, all the evaluated implants, regardless of the group they were allocated, could be categorized as "success" in the ICOI Pisa Health Scale for Dental Implants, and did not show significant difference in crestal bone loss. To the best of our knowledge, these are the first histological and clinical outcomes indicating that the use of bone chips mixed 1:1 to porcine bone in SCT could be a promising technique for the rehabilitation of patients with agenesis of the upper lateral incisors, although studies with a larger number of patients and implants, and a longer follow up are needed.

Bone Loss in Implants Placed at Subcrestal and Crestal Level: A Systematic Review and Meta-Analysis.

Background: To assess differences in marginal bone loss in implants placed at subcrestal versus crestal level. Methods: An electronic and a manual research of articles written in English from Jaunary 2010 to January 2018 was performed by two independent reviewers. Clinical trials comparing bone loss for implants placed at crestal and subcrestal level were included. Pooled estimates from comparable studies were analyzed using a continuous random-effects model meta-analysis with the objective of assessing differences in crestal bone loss between the two vertical positions. Results: 16 studies were included; 10 studies did not encounter statistically significant differences between the two groups with respect to bone loss. Three articles found greater bone loss in subcrestal implants; while 3 found more bone loss in crestal implants. A meta-analysis for randomized control trial (RCT) studies reported an average and non-statistically different crestal bone loss of 0.028 mm. Conclusions: A high survival rate and a comparable bone loss was obtained both for crestal and subcrestal implants’ placement. Quantitative analysis considering a homogenous sample confirms that both vertical positions are equally valid in terms of perimplant bone loss. However, with respect to soft tissue; in presence of a thin tissue; a subcrestal placement of the implant should be preferred as it may reduce the probability for the implant to become exposed in the future and thus avoid the risk of suffering from peri-implant pathologies.

Impact of jaw location on clinical and radiological status of dental implants placed in cigarette-smokers and never-smokers: 5-year follow-up results.

The aim of this 60 months follow-up investigation was to investigate the impact of jaw location on clinical and radiological status of dental-implant therapy in cigarette-smokers and never-smokers. Twenty-nine self-reported cigarette-smokers and 27 nonsmokers were assessed. All implants were categorized into three regions with reference to their location in the maxilla or mandible: (a) Anterior zone: implants located in anterior teeth; (b) Middle zone: Implants located in the premolar region; and (c) posterior zone: implants located in the molar region. Peri-implant crestal bone loss (CBL), bleeding-on-probing (BOP) and probing-depth (PD) ≥ 4 mm and were assessed. Level of statistical significance was set at P < .05. Mean age of cigarette-smokers (n = 29) and never-smokers (n = 27) was 44.5 years (39-51 years) and 43.6 years (35-49 years), respectively. The average duration of cigarette-smoking was 20.3 years (17-26 years). The mean periimplant PD (P < .05) and CBL (P < .05) were significantly higher in cigarette-smokers in contrast to never-smokers in all zones. No statistically significant differences in CBL, PD, and BOP were observed in the three zones of implant location among cigarette-smokers and never-smokers. Smoking enhanced PD and CBL around dental implants and this relationship was independent of site of implant placement and jaw location.

A randomized controlled clinical trial assessing initial crestal bone remodeling of implants with a different surface roughness.

The aim of current split-mouth study is to compare crestal bone loss of hybrid with moderately rough implants in patients with a bar-supported mandibular overdenture. Fully edentulous patients were enrolled for treatment with implant-supported overdentures. Each patient received two implants of which one moderately rough (Sa: 1.3 μm) and one hybrid surface implant (moderately rough implant body [Sa: 1.3 μm] and a minimally rough implant neck [Sa: 0.9 μm]). Beside the difference in implant surface the two implants are identical. After 3 and 12 months, peri-apical radiographs were taken to assess crestal bone levels and a Wilcoxon signed-rank test was used for pairwise comparison. Forty-two implants were placed in 21 patients and no failures occurred after 1 year. An overall mean crestal bone loss of 0.40 mm (SD: 0.76; range: 0-3.93) and 0.35 mm (SD: 0.59; range: 0-2.56) was registered after a mean follow-up of 3.4 and 15.8 months. There was no statistical significant difference in crestal bone loss between the different implant surfaces or between the different time intervals. From this randomized controlled trial, it can be concluded that hybrid surface implants may be a viable alternative for implant treatment in the edentulous mandible.

A randomized controlled clinical trial to assess crestal bone remodeling of four different implant designs.

It is claimed that bone remodeling is limited when the implant neck has microthreads and an internal abutment connection. However, comparative studies, excluding confounding factors, are scarce. This RCT aims to assess whether a coronal microthreaded design and an internal abutment connection affects crestal bone loss, up to one year of function. Twenty-one maxillary edentulous patients were consecutively treated for a bar supported maxillary overdenture on four different implants with respectively: internal connection and microthreads on the implant neck (I MT); internal connection, no microthreads (I NMT), external connection, with microthreads (E MT), and external connection, without microthreads (E NMT). Other design features, s.a. width, surface topography, platform switch as well as surgical placement and prosthetic protocol were consistent. Implant survival and crestal bone loss in relation to the implant type were considered the main variables and a Friedman test for ordered alternatives was used to assess the difference in crestal bone loss between the different study implants. Twenty-one patients received 83 study implants. Three implants failed within three months and required replacement. The total survival rate was 96.39% after one year and based on 21 patients and 80 implants a mean crestal bone loss of 0.25 mm (SD: 0.38; range: 0-1.48) was measured. After a follow-up of 3, 6, 12, and 21 months no statistically significant differences in crestal bone loss between the different study implants or the different time intervals could be identified. From this RCT, it is concluded that the implant-abutment connection and a microthreaded external thread configuration have limited influence on crestal bone remodeling. The latter can be considered a multifactorial process and is more dependent on other factors such as biologic considerations than on implant design.

No clinically significant differences in crestal bone loss between immediate implant placement and implants placed in healed bone: A systematic review of articles published from 1966 through 2012

No clinically significant differences in crestal bone loss between immediate implant placement and implants placed in healed bone: A systematic review of articles published from 1966 through 2012

Crestal bone changes in macrogeometrically similar implants with the implant-abutment connection at the crestal bone level or 2.5mm above: a prospective randomized clinical trial.

Crestal bone loss around dental implants is a criterion for success as this could prevent loss of implant and superstructure. The macrogeometry of the implant could influence bone remodelling when the implant-abutment connection is placed at crestal bone level or above. The aim of this study was to evaluate crestal bone remodelling in a randomized clinical prospective trial in macrogeometrically similar implants with the prosthetic connection at the crestal bone level and 2.5mm above. The null hypothesis was that there was no difference in crestal bone loss after 1year of early loading. Patients were referred to Academic Centre of Dentistry Amsterdam for implant placement. Patients were subjected to inclusion and exclusion criteria and received a minimum of two implants: an implant with the prosthetic abutment connection at the crestal bone level (minimized collar [MC], bone level) and one with the prosthetic abutment connection 2.5mm supracrestal (long collar [LC], tissue level). The mesial or distal location of each implant type was blinded for the patient and randomized. The implants were loaded splinted after 3weeks of healing. The primary outcome was bone-level change assessed after 1year of loading. Thirty-three patients fulfilled the inclusion criteria. Thirty-nine Thommen SPI ELEMENT LC implants and 39 MC were placed, and each fixed dental prosthesis was supported by one LC and one MC implant. The intraclass correlation of measures performed by the first and second X-ray examiner was as follows: on the mesial side of the MC implant 0.990 (0.980-0.995; 95% confidence interval [CI]), 0.980 (0.962-0.990; 95% CI) on the distal side of the MC implant, 0.979 (0.959-0.989; 95% CI) and 0.988 (0.978-0.994; 95% CI) on the mesial and distal side of the LC implant, respectively. The mean bone loss of the MC implant was 0.4±0.4mm. The mean bone loss of the LC implant was 0.2±0.5mm. The paired samples t-test showed a statistically significant difference (P<0.05) between the MC and LC implants. Dental implants at bone level show statistically significantly (P<0.05) more crestal bone change after 1year of loading than a tissue-level implant.

Evaluation of Crestal Bone Loss Around Implants Placed at Equicrestal and Subcrestal Levels Before Loading: A Prospective Clinical Study.

Depth of placement of implant shoulder in relation to the crestal bone positively influence bone remodelling and preservation but the role of placement depth on bone loss before loading is not very clear. To assess the effect of placement depth alone on the crestal bone loss around implant placed at subcrestal and equicrestal level before prosthetic loading. Patients reporting to the Department of Prosthodontics with the complaint of missing teeth were enrolled in the study after analysing inclusion and exclusion criteria. A total of 24 implants were planned to be placed into two groups as Group E (n=12) and Group S (n=12). Follow up radiographs after implant placement and after six months were analysed for the amount of bone loss. On six months follow up crestal bone levels of Group E were apical to Group S. Bone loss comparison between groups after six months follow up, revealed almost same mean bone loss. The implants placed at subcrestal and equicrestal level did not show difference in crestal bone loss before prosthetic loading.

Narrow- versus mini-implants at crestal and subcrestal bone levels. Experimental study in beagle dogs at three months.

The objective of this study was to evaluate the osseointegration and crestal bone loss (CBL) in two implant designs with different diameters (Mini Sky® and Narrow Sky®) implants, placed at different vertical levels at healed canine ridges. The second, third, and fourth mandibular premolars of six Beagle dogs were extracted bilaterally. After 2 months healing, four implants divided into two groups according to their diameters (i.e., Narrow Sky® and Mini Sky®) were placed in each hemi-mandible at the level of the bone crest or 2 mm subcrestally. The animals were euthanized at 12 weeks and undecalcified samples were processed for histology. Histomorphometric analysis was carried out to compare bone-to-implant contacts (BIC) and crestal bone loss (CBL). There were not significant differences in CBL between groups when the implants were placed at subcrestal bone level (p > 0.05), meanwhile the CBL was significantly higher for both groups when the implants were inserted at crestal level (p < 0.05). All implants were osseointegrated presenting a minimum BIC percentage of 56%. The major percentages of BIC were found for both groups at subcrestal level (p < 0.05). Within the limitations of this experimental study may be concluded that the implant diameter does not affect the CBL. BIC values are affected by implant diameter and design been higher for narrow implants compared to mini-implants. Subcrestal insertion of both implants favors crestal bone preservation but crestal insertion of both designs is associated with crestal bone loss The study shows that narrow implants protect peri-implant crestal bone.

Prospective study of tapered resorbable blasting media surface implant stability in the maxillary posterior area

The purpose of this study was to evaluate the stability of tapered resorbable blasting media surface implants in the posterior maxilla. From September 2008 through January 2010, 20 patients (9 men, 11 women) who were treated with tapered GS III implants at Seoul National University Bundang Hospital were identified. Thirty-eight implants (14 premolar and 24 mol/L) were placed in maxillary posterior areas. The patients' mean age was 52.1 years, and the mean follow-up period was 12.6 months after final prosthesis delivery. The implant length was 11.8 ± 1.4 mm with a diameter of 4.6 ± 0.5 mm. The 1-year survival rate was 97.4%, and the success rate was 94.7%. The implant stability quotient value at implant placement was 63.6 and 74.4 at the second surgery, which indicated a significant difference. There was no significant difference in crestal bone loss according to implant diameter or length or sinus bone graft. This study showed the favorable clinical outcome of tapered implants that were placed in the maxillary posterior area.

Immediate Loading in Mandible Full-Arch: Pilot Study in Patients With Osteoporosis in Bisphosphonate Therapy

Immediate Loading in Mandible Full-Arch: Pilot Study in Patients With Osteoporosis in Bisphosphonate Therapy

Comparative Analysis of Peri‐Implant Marginal Bone Loss Based on Microthread Location: A 1‐Year Prospective Study After Loading

The purpose of the present study was to investigate the short-term effects of microthread location on peri-implant marginal bone levels. Two types of implants, one with microthreads placed at the implant top (group A) and the other with microthreads placed 0.5 mm below the implant top (group B), were placed adjacent to each other in the partially edentulous areas of 20 patients. In total, 40 implants were placed. Bone loss around each implant was analyzed after 1 year of functional loading, and gingival parameters (modified plaque index and modified sulcus bleeding index) of the peri-implant soft tissue were evaluated. Bone losses after loading and gingival parameters were compared using the paired t test. The average bone loss was 0.16 (SD: 0.19) mm in group A and 0.30 (SD: 0.22) mm in group B after 1-year of functional loading. The paired t test revealed a significant difference in crestal bone loss between groups A and B in individual patients (P = 0.004). No significant differences were found between the two groups for the gingival parameters. Less peri-implant bone loss was observed around implants with microthreads placed at the implant top (group A) compared to those in which microthreads were placed below the top (group B). These results indicated that the microthreads acted to stabilize the peri-implant marginal bone, and their locations played an important role in the stabilization process.

Influence of Early Cover Screw Exposure on Crestal Bone Loss Around Implants: Intraindividual Comparison of Bone Level at Exposed and Non‐Exposed Implants

The objective of this study was to evaluate the influence of early exposure of the cover screw on crestal bone loss around implants. The study population consisted of 19 patients who were treated with dental implants placed using a two-stage surgical protocol and had early exposed and non-exposed implants (20 early exposed and 20 non-exposed implants). The crestal bone loss at exposed and non-exposed implants in each patient was evaluated with a periapical radiograph taken at the first surgery and at suprastructure insertion using a computerized image-analysis system. The bone loss was compared using the Wilcoxon signed-rank test. The mean crestal bone loss at exposed implants was 0.40 +/- 0.53 mm, and it was 0.18 +/- 0.26 mm at non-exposed implants. The Wilcoxon signed-rank test revealed a statistically significant difference in crestal bone loss between exposed and non-exposed implants in the same patient (P = 0.02). The early exposure of the cover screw that results in breakdown of the mucosal seal seems to accelerate early peri-implant crestal bone loss. Periodic follow-up after the first surgery may be critical for minimizing the influence of early exposure.