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The aim of study was to determine the most informative morphological criteria of maxillary dental arch for mathematical prediction of orthodontic treatment need for complete unilateral cleft lip and palate patients. Study was based on examination of 40 patients (mean age 6.4±0.4 years) with congenital non-syndromic complete unilateral cleft lip and palate according to elaborated study plan. Measurements of maxillary diagnostic models of the studied subjects were performed in 3D computerized images. The three-dimensional scanner based on the laser triangulation method was used for scanning dental casts. Analysis of diagnostic models included assessment of length, width of dental arches and their relationship anteroposteriorly and transversally, height of palate and the shape of maxillary dental arch. Dental arch relationship anteroposteriorly was assessed according to 5 Year-Old Index for complete unilateral cleft lip and palate patients. The analysis of occlusion and the form of maxillary dental arch was performed by assessment of the degree 112 of posterior and anterior crossbite. Discriminant analysis was performed by using statistical analysis software SPSS 16. The length of maxillary dental arch altitude proved to be the most credible morphological criterion for evaluation of occlusion anteroposteriorly (77.1 percent prognostic value) in children with complete unilateral cleft lip and palate in order to predict orthodontic treatment need during the period of early mixed dentition. The width of maxillary dental arch in the area of second primary molars proved to be the most credible morphological criterion for evaluation of occlusion transversally (77.8 percent prognostic value) in children with complete unilateral cleft lip and palate in order to predict orthodontic treatment need during the period of mixed dentition. Long-term follow up is required in order to confirm effectiveness of cleft care. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy of cleaning protocols for the decontamination of organic compounds from polished zirconium oxide samples., Materials and Methods: A total of 24 rectangular plate specimens were sintered from zirconium oxide. All samples were polished with commercially available polishers (coarse, fine, and superfine) and polishing paste. During the first step of the protocol, all specimens were cleaned with steam. Samples were then randomly assigned to one of three groups (n = 8 each): A, B, or C. In group A, no additional cleaning was performed, while specimens in group B underwent ultrasonic cleaning in distilled water. Group C specimens were cleaned in an ultrasonic bath with a special detergent solution. After washing, samples were subjected to energy-dispersive x-ray spectroscopy (EDX) and scanning electron microscopy (SEM) examination. In order to detect organic materials, the level of carbon atoms was measured., Results: EDX analysis revealed that samples in group A had the highest percent of carbon atoms (9.57 ± 3.67) on the surface compared to other cleaning protocols. Following the Group B cleaning protocol resulted in lower carbon levels (4.73 ± 3.56), but this difference was not significant compared to group A (P = .439). None of the specimens in group C had detectable carbon atoms (0), which implies that all wax molecules were removed (P < .05)., Conclusion: Total decontamination of organic compounds from a polished zirconium surface can be expected only following the C cleaning protocol; therefore, it is advised to employ an ultrasonic bath with detergent solution for cleaning procedures of zirconium abutments before delivery. Int J Prosthodont 2023;36:588-594.

Purpose: This is a randomized clinical trial to compare the clinical and immunological performance of ultrasmooth versus conventionally-smooth zirconia abutments placed subgingivally after a period of 1 year., Materials and Methods: Sixty-two bone level platform-switched implants (NobelParallel CC) were placed epicrestally in the mandibular molar or premolar region in 62 patients. After osseointegration, implants were restored with auto polymerizing acrylic resin crowns and subsequently randomly allocated to two groups according to the type of screw-retained zirconia crown prescribed. The control group received custom zirconia restoration with the subgingival zirconia part conventionally polished, whereas the test group implants were restored with ultra-polished zirconia abutments. Periodontal parameters (PD, PI, and BOP) and marginal bone level changes (MBLC) were recorded for each implant 2 months after insertion (T0), 1 month after final delivery of the crown (T2), and at the 1-year follow-up (T3). Immunological mediators from gingival crevicular fluid (IL-1α, IL-1ra, and TNF-α) were inspected at 1 month after provisional (T1) and accordingly at T2 and T3. Data was analyzed statistically, and significance level was set to α = 0.05., Results: After 1 year, there were no significant changes in PD control-2.18 ± 0.89 mm and test-2.5 ± 0.72 mm (p = 0.073). PD between T2 and T3 dropped significantly in the test group (p = 0.037) and remained stable in the control group. PI was not different in both groups at T0 (p = 0.518) and T2 (p = 0.817). At T3, the test group (0.9 ± 1.01) had a significantly lower PI than the control group (1.55 ± 1.23) (p = 0.035). There was no difference in BOP positive cases between groups after 1 year (control-61.3%, test-51.7%, and p = 0.455). The amount of IL-1ra decreased significantly in the test group (41.75 ± 57.58) (p = 0.001) but not in the control group (59.59 ± 70.43) (p = 0.177). MBLC for the control and test groups after 1 year were 0.68 ± 0.7 and 0.94 ± 0.65 mm (p = 0.061)., Conclusions: PD dynamics, PI, BOP, and IL-1ra revealed better outcomes around ultra-polished zirconia abutments than around conventionally polished zirconia abutments., (© 2023 by the American College of Prosthodontists.)

Purpose: To determine the effect of 0.7- and 2.4-mm transmucosal abutment height titanium bases on the crestal bone stability and peri-implant soft tissue condition of bone-level implants with platform switching in patients with vertically thick soft tissues., Materials and Methods: Sixty bone-level platform-switched implants were placed in the molar and premolar regions of both arches in 60 patients. All epicrestally inserted nonsubmerged implants had a 4.1-mm diameter and, after osteointegration, were randomly allocated into two groups: (1) the short group, with a titanium base of 0.7-mm transmucosal abutment height, and (2) the high group with a 2.4-mm height. Monolithic zirconia restorations were fabricated for all implants. Parallel intraoral radiographs were obtained after the delivery of restorations (T1) and after 1 year (T2). Crestal bone levels and peri-implant soft tissue conditions were calculated for each implant. The significance level was set at α = .05., Results: After 1 year, 55 patients were evaluated, with a mean bone loss of 0.6 ± 0.51 mm (median: 0.71, range: 0 to 2.09 mm) in the short group (23 patients) and 0.45 ± 0.59 mm (median: 0.65, range: 0 to 2.12 mm) in the high group (22 patients), showing no significant difference between groups (P = .168). A significant increase in marginal bone height was noted between the T1 and T2 time points in the short and high (P = .029 and .001, respectively) groups. The peri-implant soft tissue health parameters did not show statistically significant differences., Conclusion: Crestal bone stability after 1 year of follow-up around epicrestally placed platform-switched implants is not influenced by transmucosal abutment height, if the vertical soft tissue thickness is ≥ 3 mm.

Background: The relation between implant abutment disconnection (AD) and increased crestal bone loss is still debated., Purpose: To compare bone changes below implant-abutment junction of subcrestally placed implants between: (1) implant level restorations, that underwent four ADs and (2) implants with immediate tissue level abutment with no AD, 1 month (T2) and 1-year (T3) after final restoration delivery., Materials and Methods: Sixty-four patients received 64 bone level implants with platform-switching and conical connection in edentulous sites of posterior mandible and maxilla. All implants were placed 1.5 mm subcrestally and distributed among: (1) control group, that received a regular healing abutment and (2) test group with immediate tissue level (ITL) abutment, which was torqued to implants during surgery, transforming bone level implant to tissue level type. After 2-3 months of healing and a 1-month temporization, final zirconia-based screw-retained crowns were delivered to both groups. Crestal bone levels were calculated after final crown delivery (T2); after 1-year follow-up (T3) and compared using Mann-Whitney U test (p ≤ .05)., Results: Early bone loss of the test and control groups was 0.14 ± 0.27 mm and 0.64 ± 0.64 mm, respectively; the 0.5 mm difference was statistically significant (p = .0001). Late bone loss was 0.06 ± 0.16 mm and 0.21 ± 0.56 mm for the test and control group, respectively; the 0.15 mm difference between the groups was no more statistically significant (p = .22). Both groups displayed bone gain, 0.08 and 0.43 mm, respectively, and the overall crestal bone loss was reduced., Conclusions: Immediate tissue level abutments can significantly reduce early bone loss when measured 1 month after final prosthesis delivery, however, after 1-year follow-up, difference between the groups was no more statistically significant., (© 2021 Wiley Periodicals LLC.)

Purpose: Aims of the study were: (a) to register crestal bone loss around 1.5 mm subcrestally placed implants and epicrestally placed implants with soft tissue tenting technique, (b) to record bone remodeling in subcrestal group, and (c) to determine the increase of vertical soft tissues after tenting., Materials and Methods: Thirty-two patients with vertically thin tissues of 2 mm or less received 40 submerged bone level platform-switched implants, divided into two groups-(a) 1.5 mm subcrestally placed implants and (b) epicrestally placed implants with soft tissue tenting over 2 mm healing abutments. At the second stage surgery, implants received 4 mm healing abutments, soft tissue thickness was measured in epicrestal group, and later implants were restored with zirconia-based screw-retained single restorations. Radiological images were taken at the second stage surgery, restoration delivery and after 2 years of follow-up. Bone loss was calculated as a distance between implant neck and first radiographically visible bone-to-implant contact. Bone remodeling was calculated as a distance between the bone crest and implant neck. Mann-Whitney U test was used for statistical analysis, significance set to 0.05., Results: After 2 years of follow-up, Group 1 (subcrestal) had 0.18 ± 0.32 mm of bone loss, Group 2 (epicrestal with 2 mm healing abutment) had 0.51 ± 0.4 mm of bone loss, with statistically significant difference (P = .001). Bone remodeling in Group 1 (subcrestal) was 1.17 ± 0.51 mm. Vertical tissue thickness in epicrestal group before the intervention was 1.85 ± 0.26 and 3.65 ± 0.41 mm after the use of 2 mm healing abutment, with a statistical difference (P = .005)., Conclusion: Subcrestal implant placement can significantly reduce crestal bone loss, compared to vertical soft tissue thickening by tenting of epicrestally placed implants, although soft tissue tenting can significantly increase soft tissue thickness., (© 2020 Wiley Periodicals LLC.)

Purpose: To evaluate the surface roughness values of zirconium oxide samples that were gradually polished using a commercially available polishing system and polishing paste., Materials and Methods: A total of 50 rectangular specimens of predetermined size (10 × 10 × 3 mm) were sintered from zirconium oxide. Samples were randomly assigned to one of five groups (n = 10 each): control, coarse (Co), fine (F), super fine (SF), or polishing paste (PP). In the control group, no polishing was done; in the Co group, a coarse polisher was used; and the specimens in the remaining three groups underwent additional processing with a fine rubber abrasive. For SF and PP samples, subsequent treatment with a super fine polisher was applied. Finally, for the PP group, a goat-hair brush with diamond polishing paste was used. An optical profilometer was used to evaluate roughness average (Ra) in micrometers (μm). ANOVA and Games-Howell post hoc tests were utilized to detect differences between groups. The significance level was set to α = .05., Results: Surface roughness gradually decreased with further polishing throughout the groups: control Ra = 0.525 ± 0.099 μm; Co Ra = 0.252 ± 0.038 μm; F Ra = 0.196 ± 0.035 μm; SF Ra = 0.114 ± 0.031 μm; and PP Ra = 0.054 ± 0.020 μm. Statistically significant differences were detected among all groups (P < .05)., Conclusion: A surface roughness of 0.054 μm can be achieved if a full zirconia polishing protocol is used. Zirconium oxide can be polished to various surface roughnesses using commercially available polishing products.

Statement of Problem: How cement type and the surface treatment of a titanium base affect the retention of zirconia copings on titanium bases is unclear., Purpose: The purpose of this in vitro study was to evaluate the dislodging forces of zirconium oxide copings cemented on implant-supported titanium bases with different luting agents and to examine the influence of airborne-particle abrasion on titanium surfaces., Material and Methods: Thirty implant laboratory analogs (BioHorizons) were fixed in metal blocks, and 30 prosthetic titanium bases (BioHorizons) were tightened with 35 Ncm of torque. Zirconium oxide copings with a luting-gap size of 30 μm were produced by using the Lava (3M ESPE) technology. The specimens were bonded to the titanium bases with 3 different resin cements (G-CEM LinkAce, RelyX U200, and Ceka Site). The specimens were kept in artificial saliva at 37°C for 24 hours and then subjected to a dynamic loading of 5000 cycles with a mastication simulator (SD Mechatronic) with thermocycling between 5°C and 55°C. The tensile force was measured by using a universal testing machine (Zwick/Roell) at a crosshead speed of 5 mm/min. After the measurement, the cement was cleaned from the titanium bases and zirconia copings. The titanium bases were airborne-particle abraded with 50-μm aluminum oxide (Al 2 O 3 ) particles, and the bonding process was repeated. The statistical analysis included descriptive analysis, 2-way ANOVA, the Tukey post hoc, and simple main effect tests (α=.05)., Results: Bond strengths were significantly different according to the cement type used and before and after airborne-particle abrasion (P<.05). The cement retentiveness before airborne-particle abrasion was as follows: G-CEM LinkAce (1338 ±69 N)>RelyX U200 (665 ±36 N)>Ceka Site (469 ±22 N). The differences among all the cement types before airborne-particle abrasion were statistically significant (P<.05). After airborne-particle abrasion, retention decreased in all the groups, and the ranking of the cements' retentiveness remained the same: G-CEM LinkAce (662 ±65 N)>RelyX U200 (352 ±21 N)>Ceka Site (122 ±17 N). After airborne-particle abrasion, the differences among all the cements remained statistically significant (P<.05). The comparison within the groups before and after airborne-particle abrasion revealed that abrading the titanium bases with 50-μm Al 2 O 3 decreased the bond strength for all the tested cements., Conclusions: The cement type had a significant influence on the retention of the zirconia copings, and abrading the titanium bases with 50-μm Al 2 O 3 significantly decreased the dislodging force of the coping from the titanium base., (Copyright © 2018 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objectives: To evaluate and compare the enamel microcracks (EMCs) characteristics (qualitative and quantitative) in the form of tooth damage before and after debonding from human teeth of in vitro studies., Eligibility Criteria: Laboratorial studies evaluating EMCs characteristics before and after debonding metal and ceramic brackets from human teeth with intact buccal enamel., Information Sources: An electronic search of four databases (all databases of the Cochrane Library, CA Web of Science, MEDLINE via PubMed, and Google Scholar) and additional manual searches were carried out, without language restrictions. Studies published between 2000 and 2017 years were selected. Reference lists of the included articles were screened, and authors were contacted when necessary., Risk of Bias: The following six parameters were analyzed: blinding of examiner and outcome assessment, incomplete outcome data before bonding and after debonding, selective outcome reporting, and incomplete reporting of EMCs assessment., Included Studies: Out of 430 potentially eligible studies, 259 were screened by title and abstract, 180 were selected for full-text analysis, 14 were included in the systematic review. Seven studies were selected for the meta-analysis., Synthesis of Results: The results for EMCs characteristics were expressed as mean differences (MDs) with their 95 per cent confidence intervals (CIs), and calculated from random-effects meta-analyses. Debonding was associated with the increase in number (three studies, MD = 3.50, 95% CI, 2.13 to 4.87, P < 0.00001), length (seven studies, MD = 3.09 mm, 95% CI, 0.75-5.43, P < 0.00001), and width (three studies, MD = 0.39 µm, 95% CI, -0.01 to 0.79, P = 0.06) of EMCs. Considerable statistical heterogeneity was found for two forest plots evaluating the changes of number and length characteristics during debonding., Conclusions: There is weak evidence indicating length and width of EMCs increase following bracket removal and the scientific evidence concerning quantitative evaluation of the number parameter before and after debonding is insufficient. However, there is a strong evidence that after debonding the number of EMCs is likely to increase., Registration: No registration was performed.

Objective: To evaluate how vertical mucosal tissue thickness affects crestal bone stability around triangular-shaped bone-level implants, restored with low profile titanium bases and monolithic lithium disilicate restorations., Material and Methods: Fifty-five bone-level implants of 4.3 mm diameter were evaluated in 55 patients (22 males and 34 females, mean age 48.3 ± 3.4 years) in prospective cohort study. According to vertical mucosal thickness, patients were assigned into three groups: 1 (thin, 2 mm or less), 2 (medium, 2.5 mm) and 3 (thick, 3 mm and more). Implants were placed in posterior mandible and maxilla in one-stage approach and, after integration, were restored with single screw-retained monolithic lithium disilicate crowns, using low gingival profile titanium bases. Radiographic examination was performed after implant placement and after 1-year follow-up. Crestal bone loss was registered mesially and distally, and mean value was calculated. One-way ANOVA and Tukey's HSD tests were applied; significance was set to 0.05., Results: Mean vertical tissue thickness in 1 group was 1.76 ± 0.26 mm, 2 group-2.5 mm and 3.91 ± 0.59 mm in group 3, with statistically significant difference between all groups (p < 0.001). After 1-year follow-up, implants in group 1 (thin) had 1.25 ± 0.8 mm bone loss. Implants in group 2 (medium) had 0.98 ± 0.06, while implants in group 3 (thick) lost 0.43 ± 0.37 mm of crestal bone. Tukey's HSD test showed that differences between 1/3 and 2/3 were statistically significant (p < 0.001 and p = 0.0014, respectively), while between 1 and 2 was not significant (p = 0.310)., Conclusions: Significantly less bone loss occurs around triangular-shaped bone-level implants in thick mucosal tissues (≥3 mm), compared to medium or thin tissue biotype. Crestal bone loss did not differ between medium and thin tissues., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The study aimed at introducing current available techniques for enamel microcracks (EMCs) detection, and presenting a method for direct quantitative analysis of an individual EMC. Measurements of the detailed EMCs characteristics (location, length, and width) were taken from the reconstructed images of the buccal tooth surface (teeth extracted from two age groups of patients) employing a scanning electron microscopy (SEM) and our derived formulas before and after ceramic brackets removal. Measured parameters of EMCs for younger age group were 2.41 µm (width), 3.68 mm (length) before and 2.73 µm, 3.90 mm after debonding; for older -4.03 µm, 4.35 mm before and 4.80 µm, 4.37 mm after brackets removal. Following debonding EMCs increased for both groups, however the changes in width and length were statistically insignificant. Regardless of the age group, proposed method enabled precise detection of the same EMC before and after debonding, and quantitative examination of its characteristics.

Introduction: Our aim was to assess the possible changes in sensitivity of teeth with and without visible enamel microcracks (EMCs) up to 1 week after the removal of metal brackets., Methods: After debonding, 15 patients possessing teeth with visible EMCs and 15 subjects whose teeth were free of EMCs were enrolled in the study. For each experimental group, a control group was formed. The assessments of tooth sensitivity elicited by compressed air and cold testing were performed 5 times: just before debonding, immediately after debonding, and at 1, 3, and 7 days after debonding. Tooth sensitivity was recorded on a 100-mm visual analog scale., Results: For the patients without visible EMCs, discomfort peaked immediately after debonding and started to decrease on day 1; at 1 week after debonding, the visual analog scale scores were lower than just before debonding and immediately after debonding. For the subjects possessing teeth with visible EMCs, the pattern of sensitivity dynamic was inherently the same. However, the patients with visible EMCs showed higher visual analog scale values at each time interval., Conclusions: Debonding leads to a short-term increase in tooth sensitivity. EMCs, a form of enamel damage, do not predispose to greater sensitivity perception in relation to bracket removal., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To find a correlation between the severity of enamel microcracks (EMCs) and their increase during debonding and residual adhesive removal (RAR)., Materials and Methods: Following their examination with scanning electron microscopy (SEM), 90 extracted human premolars were divided into three groups of 30: group 1, teeth having pronounced EMCs (visible with the naked eye under normal room illumination); group 2, teeth showing weak EMCs (not apparent under normal room illumination but visible by SEM); and group 3, a control group. EMCs have been classified into weak and pronounced, based on their visibility. Metal brackets (MB) and ceramic brackets (CB), 15 of each type, were bonded to all the teeth from groups 1 and 2. Debonding was performed with pliers, followed by RAR. The location, length, and width of the longest EMCs were measured using SEM before and after debonding., Results: The mean overall width (Woverall) was higher for pronounced EMCs before and after debonding CB (P < .05), and after the removal of MB. Pronounced EMCs showed greater length values using both types of brackets. After debonding, the increase in Woverall of pronounced EMCs was 0.57 µm with MB (P < .05) and 0.30 µm with CB; for weak EMCs, - 0.32 µm with MB and 0.30 µm with CB., Conclusions: Although the teeth having pronounced EMCs showed higher width and length values, this did not predispose to greater EMCs increase after debonding MB and CB followed by RAR.

Background: Numerous studies have shown the superiority of platform-switched implants in preserving crestal bone as compared with platform-matched implants. However, the influence of initial soft tissue thickness on development of crestal bone loss has not been addressed in previous studies; thus, further research is needed., Purpose: To evaluate crestal bone levels around platform-switched implants placed in thin and thick mucosal tissue., Materials and Methods: Eighty patients (38 male and 42 female, mean age 44 ± 3.34 years) received 80 bone-level implants of 4.1 mm in diameter with platform switching (Institut Straumann AG, Basel, Switzerland). Tissue thickness was measured, and cases were distributed to Group 1, with thin soft tissue (2 mm or less, n = 40), and Group 2, with thick tissue (more than 2 mm, n = 40). Implants were placed with a one-stage approach and restored with screw-retained restorations. Radiographic examination was performed after implant placement, 2 months after healing, after restoration, and at 1-year follow-up post-reconstruction. Crestal bone loss was calculated. The Mann-Whitney U-test was applied, and significance was set to p ≤ .05., Results: Implants in Group 1 (thin tissue) showed 0.79 mm of bone loss after 2 months. After 1-year follow-up, bone loss was 1.17 mm. Implants in Group 2 (thick tissue) showed bone loss of 0.17 mm after 2 months of implant placement and 0.21 mm after 1-year follow-up. The differences between groups were significant (p < .001) at both time points., Conclusions: It can be concluded that platform switching does not prevent crestal bone loss if, at the time of implant placement, mucosal tissue is thin. In thick soft tissue, use of platform-switched implants maintained crestal bone level with minimal remodeling., (© 2014 Wiley Periodicals, Inc.)

Background: The depth of the cementation margin has an influence on the amount of cement remnants around implants. However, the role of other clinical factors is still not clarified., Purpose: The aim of the study was to evaluate the correlation between undetected cement and (i) location of the implant, (ii) implant diameter, and (iii) undercut., Materials and Methods: Sixty-five patients were treated with single metal-ceramic restorations on implants. The undercut between the restoration and the tissue was measured. After cementation, the restoration-abutment unit was unscrewed. All quadrants of the specimens were photographed and analyzed. The ratio between total restoration area/peri-implant tissue area and area of cement remnants was calculated in pixels. Significance was set to 0.05., Results: Sixty-five metal-ceramic restorations were placed on 65 implants (39 molars, 22 premolars, 4 anteriors; 21 implants had a diameter of 3.5 mm, 34 of 4.0 mm, 10 of 5.0 mm). An undercut of 1 mm was found in 118 sites, 2 mm in 96 sites, and 3 mm in 46. The percentages of soft tissue and restoration, respectively, covered by cement were as follows: molars 4% and 7%; premolars 3.8% and 7.3%; anteriors 3% and 3.4%; 3.5 mm diameter 3.3% and 7.4%; 4.0 mm 7.7% and 7.7%; 5.0 mm 3.9% and 2.1%; 1-mm undercut 3.5% and 5.4%; 2-mm 4% and 8.1%; 3-mm 4.8% and 8.4%. The relationship between amount of cement remnants and implant location was insignificant (p > 0.05) for both soft tissue and the specimen, but significant relationships with amount of cement remnants were found for diameter (p = 0.026 for soft tissue, p = 0.600 for specimen) and undercut (p = 0.004 for soft tissue, p = 0.046 for specimen)., Conclusion: If cemented crown restoration is desired, undercuts should be reduced to a minimum for better removal of cement excess, irrespective of the diameter and location of the implants in the mouth., (© 2013 Wiley Periodicals, Inc.)

Background: It has been shown that thin mucosal tissues may be an important factor in crestal bone loss etiology. Thus, it is possible that mucosal tissue thickening with allogenic membrane might reduce crestal bone loss., Purpose: The purpose of this study was to evaluate how implants with traditional connection maintain crestal bone level after soft tissue thickening with allogenic membrane., Materials and Methods: One hundred three patients received 103 internal hex implants of 4.6 mm diameter with regular connection. According to gingiva thickness, patients were assigned into A (thin tissues, n = 34), B (thin, thickened with allogenic membrane, n = 35), and C group (thick tissues, n = 34). Groups A and C had one-stage approach, and in group B, implants were placed in two stages. Radiographic examination was performed after implant placement, 2 months after healing, after restoration, and after 1-year follow-up. Crestal bone loss was calculated medially and distally. Significance was set to 0.05., Results: After 1-year follow-up, implants in group A had 1.65 ± 0.08-mm bone loss mesially and 1.81 ± 0.06 mm distally. Group B had 0.31 ± 0.05 mm mesially and 0.34 ± 0.05 mm distally. C group implants experienced bone loss of 0.44 ± 0.06 mm mesially and 0.47 ± 0.07 mm distally. Differences between A and B, and A and C were significant (p = .000) both mesially and distally, whereas differences between B and C were not significant mesially (p = .166) and distally (p = .255)., Conclusions: It can be concluded that thin mucosal tissues may cause early crestal bone loss, but their thickening with allogenic membrane may significantly reduce bone resorption. Implants in naturally thick soft tissues experienced minor bone remodeling., (© 2013 Wiley Periodicals, Inc.)

Objective: To compare how laser-microtextured implants and implants with platform switching maintain crestal bone stability in thin peri-implant tissues., Material and Methods: Thirty laser-microtextured implants of 4.6 mm diameter (Tapered Internal Laser-Lok, BioHorizons, Birmingham, AL, USA; Group 1) and 30 implants with platform switching of 5/4 mm diameter (Certain Prevail; Biomet/3i, Palm Beach Gardens, FL, USA; Group 2) were placed in 30 patients (12 males and 18 females, mean age 42.3 ± 2.4) with thin mucosal tissues (≤2 mm). Implants were placed in posterior mandible in one-stage approach and after integration were restored with screw-retained metal-ceramic restorations. Radiographic examination was performed after implant placement, 2 months after healing, at prosthetic restoration delivery and after 1-year follow-up. Mean crestal bone loss was calculated, Mann-Whitney U-test was applied, and significance was set to 0.05., Results: After 2 months of healing, the crestal bone loss was 0.71 ± 0.25 mm SD (range, 0.25-1.6 mm) and 1.02 ± 0.25 mm SD (range, 0.6-1.55 mm) in groups 1 and 2, respectively (P = 0.001). At restorations' delivery, the crestal bone loss was 1.10 ± 0.30 mm SD (range, 0.65-1.85 mm) and 1.37 ± 0.27 mm SD (range, 0.90-1.80 mm) in groups 1 and 2, respectively (P = 0.001). After 1-year follow-up, the crestal bone loss was 1.41 ± 0.42 mm SD (range, +0.1-2.30 mm) and 1.43 ± 0.23 mm SD (range, 1-1.80 mm) in groups 1 and 2, respectively (P = 0.976)., Conclusions: Laser-microtexturing of implant collar or platform-switched implant/abutment connection did not eliminate crestal bone loss, if at the time of implant placement vertical soft tissue thickness was ≤2 mm. However, laser-microtextured implants may present less proximal bone loss than platform-switching implants in the period before implant loading., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The objective of this in vitro study was to evaluate the effect of the enamel cracks on the tooth damage during the debonding. Measurements of the cracks characteristics (visibility, direction, length, and location) were performed utilizing a scanning electron microscopy (SEM) technique and mathematically derived formulas (x=h/30, l=n*x) before and following the removal of mechanically retained metal and ceramic brackets. The likelihood of having greater extent enamel defects was higher for the teeth with pronounced cracks (odds vatios, OR=3.728), increased when the crack was located in more than one zone of the tooth (OR=1.998), and the inclination did not exceed 30-45° (OR=0.505). Using ceramic brackets the risk of greater amount tooth structure defects raised 1.45 times (OR=1.450). Enamel crack showing all these characteristics at the beginning of the orthodontic treatment and the use of ceramic brackets might predispose to higher risk of greater extent tooth surface damage after the debonding by 20.4%.

Objectives: The purpose of this study was to determine the relationship between patients with a history of periodontitis and development of cement-related peri-implant disease., Materials and Methods: Seventy-seven patients with 129 implants for this retrospective analysis were selected from completed implant cases that were scheduled for regular maintenance or had experienced mechanical or biological complications between years 2006 and 2011 in private practice. Implants with extracoronal residual cement and implants without cement remnants were analyzed. The selected cases were further divided into two groups--implants in patients with history of periodontitis (1) and implants in periodontitis-free individuals (2). The selection of these groups was made on the basis of treatment history and orthopantomograph. As a control group, a set of 238 screw-retained implant restorations, delivered to 66 patients during the same period of time was examined. The incidence of peri-implant disease among implants in all groups was calculated., Results: Peri-implant disease was evident in 62 of 73 implants with cement remnants (85%). All implants in group 1 developed peri-implantitis--4 early and 35 delayed disease cases. In the periodontally healthy group, 20 of 31 implants were diagnosed with peri-implant mucositis, 3 implants had early peri-implantitis, and 11 implants with cement remnants did not develop biological complications. In the group of implants without cement remnants, peri-implant disease was diagnosed in 17 of 56 cases (30%). In contrast, only two occurrences of peri-implant disease were registered in the control group of screw-retained restorations (1.08%)., Conclusions: Implants with cement remnants in patients with history of periodontitis may be more likely to develop peri-implantitis, compared with patients without history of periodontal infection., (© 2012 John Wiley & Sons A/S.)

The purpose of this study was to evaluate and compare enamel micro-crack characteristics of adult patients before and after removal of metal brackets. After the examination with scanning electron microscopy (SEM), 45 extracted human teeth were divided into three groups of equal size: group 1, the teeth having enamel micro-cracks, group 2, the teeth without initial enamel micro-cracks, and group 3, control group to study the effect of dehydration on existing micro-cracks or formation of new ones. For all the teeth in groups 1 and 2, the same bonding and debonding procedures of metal brackets were conducted. The length and width of the longest enamel micro-crack were measured for all the teeth before and after removal of metal brackets. The changes in the location of the micro-cracks were also evaluated. In group 3, teeth were subjected to the same analysis but not bonded. The mean overall width of micro-cracks after removal of metal brackets was 3.82 μm greater than before bonding procedure (P < 0.05). Also, a significant difference was noticed between the width of micro-cracks in first zone (cervical third) and third zone (occlusal third) after debonding procedure (P < 0.05). New enamel micro-cracks were found in 6 of 15 (40 per cent) examined teeth. Greatest changes in the width of enamel micro-cracks after debonding procedure appear in the cervical third of the tooth. On the basis of this result, the dentist must pay extra care and attention to this specific area of enamel during removal of metal brackets in adult patients.

Objective: To evaluate the amount of undetected cement after cementation and cleaning of implant-supported restorations., Materials and Methods: Fifty three patients were treated with 53 single implant-supported metal-ceramic restorations. The subgingival location of the margin of each implant was measured with a periodontal probe mesially, distally, buccaly, and lingually(,) resulting in 212 measurements. The data were divided into four groups: equally with tissue level (14 samples), 1 mm subgingivally (56), 2 mm (74), and 3 mm (68) below tissues contour. Metal-ceramic restorations were fabricated with occlusal openings and cemented on standard abutments with resin-reinforced glass-ionomer. After cleaning, a radiograph was taken to assess if all cement had been removed. Then the abutment/crown unit was unscrewed for evaluation. All quadrants of the specimens and peri-implant tissues were photographed and analyzed with Adobe Photoshop. Two proportions were calculated: (1) the relation between the cement remnants area and the total area of the abutment/restoration and (2) the relation between the cement remnants and the total area of implant soft tissue contour. Significance set to 0.05., Results: Excess on the crown groups: 1 (0.002 ± 0.001); 2 (0.024 ± 0.005); 3 (0.036 ± 0.004); 4 (0.055 ± 0.007). Undetected excess increased when the margin was located deeper subgingivally (P = 0.000), significant difference was found among all groups (P ≤ 0.05). Remnants in the soft tissue groups: 1 (0.014 ± 0.006); 2 (0.052 ± 0.011); 3 (0.057 ± 0.009); 4 (0.071 ± 0.012). The increase of the remnants was statistically reliable (P = 0.0045), significant difference was found between group 1 and 2 (P ≤ 0.05). Radiographic evaluation showed that cement remnants mesially were visible in four cases of 53 or 7.5%, and in six cases of 53 distally (11.3%)., Conclusions: The deeper the position of the margin, the greater amount of undetected cement was discovered. Dental radiographs should not be considered as a reliable method for cement excess evaluation., (© 2012 John Wiley & Sons A/S.)

Statement of Problem: Subgingival positioning of a single dental implant may result in a less stable impression coping in a polymerized impression material., Purpose: The purpose of this study was to evaluate the influence of a single dental implant placement depth and different impression materials on the stability of an open tray impression coping., Material and Methods: Six polyvinyl chloride-based plastic models with single embedded internal hexagon implant analogs were fabricated. The implant analogs were placed equally with their surface 0, 1, 2, 3, 4, or 5 mm below the simulated gingival margin. Open tray impression copings were connected to the embedded implant analogs, and impressions were made with different vinyl polysiloxane (VPS) impression materials, polyethers, and an addition silicone-based occlusal registration material. The laboratory analogs were connected to the impression copings and the plastic trays were placed in a locking device. A measuring device, consisting of a compression force gauge connected to a platform moving at a speed of 3.2 mm/s, was fabricated. The impression trays were fixed so that the pole of the force gauge would touch the surface of the implant analog in the same place and push it 1.0 mm. Measurements of each specimen were made 5 times. Statistical analysis was performed with a 1-way ANOVA, the Tukey test, and the Pearson correlation coefficient (α=.05)., Results: There was a significant negative correlation between the dental implant placement depth and the force needed to move the impression coping (P<.05). In all depth groups, the impression coping was significantly more stable when the impressions were made with the occlusal registration material (P<.05)., Conclusions: As the dental implant placement depth increased, the force needed to move the impression coping decreased. The coping was significantly more stable when an occlusal registration material was used to make the impression., (Copyright © 2012 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.)

The aim of this study was to estimate the average disintegration temperature of three dental cements used for the cementation of the implant-supported prostheses. One hundred and twenty metal frameworks were fabricated and cemented on the prosthetic abutments with different dental cements. After heat treatment in the dental furnace, the samples were set for the separation to test the integration of the cement. Results have shown that resin-modified glass-ionomer cement (RGIC) exhibited the lowest disintegration temperature (p<0.05), but there was no difference between zinc phosphate cement (ZPC) and dual cure resin cement (RC) (p>0.05). Average separation temperatures: RGIC - 306 ± 23 °C, RC - 363 ± 71 °C, it could not be calculated for the ZPC due to the eight unseparated specimens. Within the limitations of the study, it could be concluded that RGIC cement disintegrates at the lowest temperature and ZPC is not prone to break down after exposure to temperature.

Unlabelled: The objective of the present study was to assess the public accessibility of orthodontic care in Lithuania., Material and Methods: In 2008, a request for the information about various aspects of public orthodontic care during 2000-2007 in Lithuania was submitted to the State Patients' Fund at the Ministry of Health. The data on the demographic distribution of orthodontists in Lithuania were received from the Lithuanian Dental Chamber. The authors of the paper also analyzed the national legislation regulating the State Patients' Fund expenditure on orthodontic care and treatment., Results: In 2007, there were 73 orthodontists-practitioners in Lithuania, most of them highly concentrated in major cities and towns: most of them were practicing in Vilnius (22) and Kaunas (20), while there were only 5 orthodontists in Klaipeda, 4 in Siauliai, 3 in each of Panevezys and Marijampole. The public orthodontic treatment is rendered only to patients suffering from most severe pathologies. With the constantly increasing expenditure of the State Patients' Fund, the national public orthodontic care system definitely undergoes significant development: the number of patients who received the treatment with removable and with fixed orthodontic appliances was gradually increasing during 2002-2007, with however, a very small number of new facilities for ambulatory treatment facilities of orthodontists (consultations included). The number of patients who received treatment with removable orthodontic appliances was specifically higher in Siauliai and Telsiai, Panevezys and Utena districts, with fixed orthodontic appliances - in Vilnius and Alytus, Kaunas and Marijampole, Panevezys and Utena regions. The analysis of the availability of public orthodontic treatment showed a marked increase in the number highly-specialized ambulatory facilities in Vilnius and Alytus district in 2002-2007., Conclusions: Specialists providing orthodontic treatment in the country are highly concentrated, while in general public orthodontic treatment undergoes development at the moment. The accessibility of orthodontic treatment in Lithuania, especially in the regions distant from Vilnius and Kaunas, remains inadequate.

Unlabelled: This study evaluates dental occlusion and dental arch parameters of 5-6 year old children with unilateral cleft lip and palate (UCLP) treated and untreated orthodonticly before lip plastic with noncleft children. The aim of the study was to verify whether early orthodontic treatment improves deciduous dental arch relationship of children with unilateral cleft lip and palate.135 casts of 5-6 year old children from Riga and Vilnius were evaluated. 90 casts from children with UCLP (45 - got early orthodontic treatment, 45 - without early orthodontic treatment) and 45 casts from noncleft children. All patients with UCLP had surgically closed lip and palate; five-Year-Olds, Index was used to assess dental arch relationship of UCLP patients. Measurements of dental arch length, canine and molar arch width was taken similar to Bland and Altman method., Statistical Analysis: the difference of the mean values was tested using t-test between and within groups: UCLP-1 (without early orthodontics), UCLP-2 (treated orthodonticaly before lip plastic) and control group - noncleft children). Measurements were performed by two calibrated orthodontists, mean error was calculated according to the Dalberg method. Measurement error was less than 1 mm. Measurements showed that the occlusion parameters and transverse distance between deciduous molars of UCLP-1 group differed from the occlusion of UCLP-2. Children who had got early orthodontics showed better growth of the maxillae. More cases with positive overjet and meziodistal or distal deciduous molar relationship had treated with early orthodontics. Maxillary width between deciduous molars was statistically significant wider in children with UCLP who had early orthodontic treatment comparing with untreated children. Growth of mandible was not inhibited and did not differ treated and untreated children with UCLP and control group.