Evaluation with a Coordinate-Measuring Machine of Dimensional Accuracy of the Abutment Duplication Technique in Cement- Retained Implant Restoration.

PURPOSE: To evaluate the effectiveness and accuracy of a proposed duplication technique in terms of one- and three-dimensional discrepancies between an original abutment and polyurethane duplicates obtained through a conventional workflow in single-implant rehabilitation. MATERIALS AND METHODS: A titanium, shoulderless abutment was chosen for a single-implant cemented rehabilitation. The master cast was made using a plastic-based die system, and the implant portion was separated. The implant section was consecutively duplicated eight times using a manual technique with polyvinyl siloxane and unfilled polyurethane resin as impression and die materials. The duplicates were analyzed with a coordinate-measuring machine (SmartScope Flash 200, Optical Gaging Products): one- and three- dimensional discrepancies were determined for each duplicate on 20 analysis points (A to T) located on the abutment surface. Changes in the abutment radius were also calculated to estimate the effects on cement thicknesses. RESULTS: One-dimensional discrepancies were -0.5 Å} 61.2 µm, -6.6 Å} 39.7 µm, and -19.4 Å} 47.8 µm on the X, Y, and Z axes, respectively; three-dimensional variation was -66.4 Å} 60.1 µm. Friedman test showed no significant difference between duplicates' one-dimensional variations on X (P = .059), Y (P = .156), or Z (P = .223) axes; a significant difference was found regarding three-dimensional changes (P < .001). Dunn test showed higher discrepancies on the X axis and on the abutment head. Mean variation of the abutment radius was -12.09 µm. CONCLUSIONS: The abutment duplication technique was shown to be an accurate and repeatable procedure for single cementable restorations.

Analysis of ultra-short implants with different angulations: a retrospective case-control study with 2 to 9 years of follow-up.

OBJECTIVES: Does the angulation of ultrashort implants influence the stability of the peri-implant bone? The present study aimed to evaluate the effectiveness of non-axial ultrashort implants after 2 to 9 years of follow-up in resorbed alveolar ridges. MATERIALS AND METHODS: All partially edentulous patients with ultrashort implants (< 6 mm) used in the posterior region of an atrophic mandible or maxilla, to support partial dentures in conjunction with standard implants, were included in this study. Peri-implant bone loss, success and survival rates, crestal bone levels, crown-to-implant ratio and implant angulation were measured for each implant. Implants were divided into two groups: straight implants with angulation < 17° (control group) and tilted implants with angulation > 17° (test group). Statistical analysis was used to find any significant differences between the two study groups and to investigate significant linear correlations among all the variables (p = 0.05). RESULTS: A total of 42 ultrashort implants with a mean of 4 years of follow-up were included: 20 ultrashort axially loaded implants and 22 tilted implants. Mean crestal bone levels from baseline loading to maximum follow-up did not reveal statistical differences in regard to PBL; mean success and survival rates were 100% in all groups. CONCLUSIONS: PBL, success and survival rates of axial ultrashort implants and tilted ultrashort implants are comparable to those of conventional implants. CLINICAL RELEVANCE: This retrospective study revealed that ultrashort implants, even when placed with an angulation > 17°, can safely be used to support partial fixed prostheses. Further prospective clinical studies with larger samples and prospective design are needed to confirm these findings.

Evaluation with a coordinate measuring machine of dimensional accuracy of the Abutment Duplication Technique in cement-retained implant restoration.

PURPOSE: To evaluate the effectiveness and accuracy of a proposed duplication technique in terms of one- and three-dimensional discrepancies between an original abutment and polyurethane duplicates obtained through a conventional workflow in single-implant rehabilitation. MATERIALS AND METHODS: A titanium shoulder-less abutment was chosen for a single-implant cemented rehabilitation. The master cast was made using a plastic-based die system, and the implant portion was separated. The implant section was consecutively duplicated eight times using a manual technique with polyvinyl siloxane and unfilled polyurethane resin as impression and die materials. The duplicates were analyzed with a coordinate-measuring machine (SmartScope Flash200, OGP): one- and three- dimensional discrepancies were determined for each duplicate on 20 analysis points (A-T) located on the abutment surface. Changes in the abutment radius were also calculated to estimate effects on cement thicknesses. RESULTS: One-dimensional discrepancies were -0.5 µm ± 61.2µm, ¬-6.6 ± 39.7 µm, and -19.4 ± 47.8 µm on X, Y, and Z axes, respectively; three-dimensional variation was -66.4 ± 60.1 µm. The Friedman test showed no significant difference between duplicates' one-dimensional variations on X (p = 0.059), Y (p = 0.156), or Z (p = 0.223) axes; a significant difference was found regarding three-dimensional changes (p < 0.001). The Dunn test showed higher discrepancies on the X axis and on the abutment head. Mean variation of the abutment radius was -12.09 µm. CONCLUSION: The abutment duplication technique was shown to be an accurate and repeatable procedure for single cementable restorations.

Nonsurgical Rhinoplasty With the Novel Hyaluronic Acid Filler VYC-25L: Results Using a Nasal Grid Approach.

BACKGROUND: Nonsurgical aesthetic treatment of the nose is becoming increasingly popular. VYC-25L is a novel hyaluronic acid product with the high G' and cohesivity required of a nasal filler. OBJECTIVES: The authors sought to assess the safety and efficacy of VYC-25L for treatment of the nose utilizing a previously published, grid-based protocol. METHODS: This was a retrospective, single-center analysis of data from adult patients undergoing treatment of the nose with VYC-25L between February and April 2019 utilizing the grid system as the reference for injection quantity and sequencing. Specific procedures included correction of inadequate projection, deep glabella treatment, correction of a nasal hump, and adjustment of the nasolabial angle and columella. Patients were followed-up for 6 to 9 months. RESULTS: A total of 61 patients were included in the analysis (mean age, 32 ±â€…3 years; n = 45 females [74%]). At 2 weeks posttreatment, a high degree of defect correction was confirmed based on independent evaluation, with all patients scoring 9 or 10 on a 10-point visual analog scale. Fifty-nine of 61 patients (97%) self-assessed the degree of correction as "adequate." Results were stable at 3- and 6-month follow-up visits. Complications recorded were bruising (n = 15, 25%), asymmetry (n = 2, 3%), and hematoma (n = 1, 2%). All resolved rapidly. There were no cases of infection, bumps, or skin necrosis. CONCLUSIONS: VYC-25L is safe and efficacious for treatment of the nose, with high levels of patient satisfaction. It has potential to be a valuable tool in nonsurgical rhinoplasty.

Influence of crown-implant ratio on implant success rate of ultra-short dental implants: results of a 8- to 10-year retrospective study.

OBJECTIVES: The use of short implants has been suggested in recent years as an option for facilitating prosthetic restoration in resorbed jawbones. The aim of the present study was to determine how implant success rate is affected in the long term when ultra-short implants are rehabilitated with fixed restorations, resulting in a crown to implant (C/I) ratio of more than 3:1. MATERIALS AND METHODS: The study was conducted as an analysis on all patients operated from December 2005 to November 2007 with ultra-short dental implants. All implants were sintered porous-surfaced (SPS) with a length of 5 mm and a diameter of 5 mm (5 × 5 mm) and were restored with a single crown or a fixed dental prosthesis (FDP). Data collected included implant positioning site, crestal bone levels (CBL), and clinical and anatomical C/I ratios, and pre-established success criteria were used to evaluate the success rate of the implants. Statistical analysis was used to determine any significant differences or correlations (p = 0.05). RESULTS: Forty-one patients completed the follow-up and were eligible for this retrospective study on a total of 50 ultra-short SPS implants. The mean follow-up was 9.5 years (range 8.3 to 10.2 years). Three of the 50 implants failed because they were lost due to peri-implantitis, while all the other 47 met the pre-established success criteria giving an overall implant success rate of 94%. During the follow-up period, the mean peri-implant bone loss (PBL) was 0.41 + 0.36 mm. CONCLUSIONS: This study shows that ultra-short SPS implants can prove a reliable solution for prosthetic restoration in patients with severe alveolar bone atrophy. In selected patients with a sufficient bone width, ultra-short implants with a resulting C/I ratio of more than 3:1 presented no contraindications. CLINICAL RELEVANCE: In selected cases, ultra-short implants may represent an alternative to bone augmentation procedures and a long-term predictable solution.

Clinical and Esthetical Evaluation of 79 Lithium Disilicate Multilayered Anterior Veneers with a Medium Follow-Up of 3 Years.

OBJECTIVES: Primary aim of this study was to evaluate survival rate of lithium disilicate veneers in upper and lower anterior teeth. Secondary aims were to evaluate changing in proportions of teeth before and after restorations and to assess mean thickness of the veneers. MATERIALS AND METHODS: Seventy-nine upper and lower lithium disilicate veneers were made in 13 patients with worn teeth. Mean follow-up was 3 years. To perform anterior definitive rehabilitations, malocclusions and loss of vertical dimension were treated by full mouth rehabilitations to obtain proper occlusal conditions. Veneers were made of lithium disilicate core and fluorapatite-based ceramic stratification. Survival rate was calculated by Kaplan-Meier analysis. Changing in teeth proportion before and after restorations was analyzed by a paired t-test. Descriptive statistics of thickness values were also performed. RESULTS: One case of detachment was observed with a 98.7% survival rate. Teeth's proportions were preserved although the first upper right incisor and canine changed in dimension. CONCLUSIONS: Lithium disilicate veneers in esthetical rehabilitations of worn teeth proved to be an effective way of treatment in a medium follow-up of 3 years. Proportions seemed to be maintained with a minimum dental removal.

Apps for oral hygiene in children 4 to 7 years: Fun and effectiveness.

BACKGROUND: Nowadays apps in preschool age are largely used in learning improvement. The aim of this work was to test effectiveness of apps in improving oral hygiene in children patients aged from 4 to 7 years and evaluating correlation between parents educational attainment and children oral hygiene. MATERIAL AND METHODS: 100 patients aged from 4 to 7 years were randomly assigned by an external office in the study group (SG: 32 females, 18 males) and in the control group (CG: 28 females and 22 males). Plaque index (PI) and carious lesions localisation were detected. At baseline all patients and one of the parents were instructed at chair-side about the proper oral hygiene techniques. SG patients were also given app as an aid in oral hygiene practice. Follow-up was 12 months. Measurements were made every three months at chair-side visits. Information about children compliance in oral hygiene and educational level of parents were obtained by questionnaires at t0 and after 12 months. RESULTS: SG patients showed stronger oral hygiene and PI lower than those in CG. Questionnaire showed higher compliance of SG patients and parents educational level seemed to affect children oral hygiene. CONCLUSIONS: Apps in children allowed achieving encouraging results with improvement of oral hygiene and health. Key words:Apps, oral hygiene compliance, children oral hygiene, motivation, educational attainment.

Evaluation of Crestal Bone Loss Around Straight and Tilted Implants in Patients Rehabilitated by Immediate-Loaded Full-Arch All-on-4 or All-on-6: A Prospective Study.

The aim of this prospective study was to compare implant success rate and crestal bone loss around tilted and straight implants supporting immediate-loading full-arch rehabilitations. Twenty consecutive patients with edentulous jaws treated between June 2013 and July 2015 who satisfied all inclusion and exclusion criteria were included in the study. All patients were rehabilitated through a full-arch restoration supported by 4 or 6 immediately loaded implants. Clinical and radiographic examinations were scheduled every 12 months to evaluate implant success rates and crestal bone levels. Significant differences in crestal bone levels and success rates between straight and tilted implants were investigated by means of independent statistical analysis; differences were regarded as significant if P < .05. Seventy straight and 50 tilted implants were placed to rehabilitate 14 mandibles and 12 maxillae in 20 patients. After a follow-up of 12 to 36 months, survival rate was 97.1% for straight implants and 96.0% for tilted implants; while success rates were 94.3% and 94.0%, respectively. Success and survival rates were not significantly different (P > .05). Change in crestal bone level was 0.5 ± 0.4 mm for straight implants and 0.6 ± 0.4 mm for tilted implants (P > .05). Straight and tilted implants seemed to have similar behavior after immediate loading rehabilitations. After functional loading, straight and tilted implants did not differ significantly in clinical outcome.

Relationship Between Crestal Bone Levels and Crown-to-Implant Ratio of Ultra-Short Implants With a Microrough Surface: A Prospective Study With 48 Months of Follow-Up.

The aim of this cohort study was to investigate the relationship between crestal bone levels and crown-to-implant ratio of ultra-short implants, after functional loading. Sixty patients with single or partial edentulism and alveolar bone atrophy were enrolled and treated between December 2009 and January 2016. Without using bone-grafting procedures, patients were rehabilitated with ultra-short implants characterized by a microrough surface and a 6-mm length. Clinical and anatomical crown-to-implant (C/I) ratios and crestal bone levels (CBL) were measured after a follow-up period ranging from 12 to 72 months; all peri-implant and prosthetic parameters were recorded. The data collected were statistically analyzed ( P = .05). A total of 47 patients with 66 ultra-short implants were completely followed up according to described protocol. The mean follow-up was 48.5 ± 19.1 months. The mean anatomical C/I ratio was 2.2, while the mean clinical C/I ratio was 2.6 ± 0.6 at baseline and 2.8 ± 0.6 at the last follow-up appointment. Mean CBL as calculated at the baseline was 0.7 ± 0.5 mm, while at the last appointment it measured 1.0 ± 0.5 mm. The overall implant-based success rate was 96.9%, and the mean peri-implant bone loss (PBL) was 0.3 ± 0.3 mm. No statistically significant relationship was found between anatomical or clinical C/I ratio and PBL. Ultra-short implants appear to offer a predictable solution for implant-prosthetic rehabilitation in patients with edentulism and bone atrophy. A high percentage of implants were successful, with minimal crestal bone loss. The high C/I ratio did not appear to influence either peri-implant bone loss or prosthetic complication rates.

Injectable profiloplasty: Forehead, nose, lips, and chin filler treatment.

INTRODUCTION: We propose a medical filler treatment algorithm of the profile which includes forehead, nose, and chin and to evaluate profilometric results and complications. MATERIALS AND METHODS: 83 case reviews of associated liquid forehead, nose, and chin plasty performed consecutively from 2014 to 2016. We monitored the horizontal and vertical sagittal stability into two age group: <40 y.o. and >40 y.o. using profilometric Arnett analysis measurements on the F, Gb, Na, Nd, Nt, Sn, ULA, LLA, B, Pg, and Gn soft-tissue points. RESULTS: The results at both 3 and 6 months were consistent with the normal ranges indicated by Arnett, with a 0.8 mm maximum of defect/excess. Forehead treatment was performed in 51 (61.4%) patient. Patients >40 y.o. always needed a global correction of the forehead profile. We performed nasal treatment in 83 (100%) patient, acute nasolabial angles was the more frequent nasal defect. The lips were injected in 59 patients (71.1) more frequently >40 y.o. In 83 (100%) patients we perform a chin augmentation. The average advancement of the chin was 3 mm. CONCLUSIONS: The correction of the projection of the forehead, of the profile and shape of the nose, of the lips and chin as well as an overall improvement in face aesthetics and harmony gives a good solution in patients avoiding the need for a surgical intervention, scars and cost of general anesthesia, thus providing the optimum in patient satisfaction.

Osteotomy in Genioplasty by Piezosurgery.

BACKGROUND: The chin is the most prominent and median sector of the lower third of the face giving harmony to nose and lips. The authors present the application of piezoelectric scalpel for the correction of different chin deformities. The distinctive characteristics of this device allow the authors to avoid or reduce the immediate genioplasty complications. METHODS: Fifty-five patients of defective chin have been treated from January 2006 to April 2008. Intraoral genioplasty was performed during the correction of dentofacial dysmorphisms or associated with nasal surgery. The authors used a piezoelectric cutting device to perform different osteotomies and if necessary, interpositional graft was used to stabilize bony segments. RESULTS: Piezosurgery has been associated with a fewer number of postoperative complications, especially as regard intraoperative bleeding, nerve injuries (immediate and late), hematomas and seromas, asymmetry (immediate and early). The mean time for completing the complete procedure of genioplasty with piezosurgery was almost the same compared with the saw and drill. CONCLUSION: Genioplasty represents one of the most common ancillary procedures and may be associated with corrective surgery of dentofacial dysmorphisms. Mental nerve injuries, asymmetries, intraoperative bleeding are the main immediate complications of genioplasty. Distinctive characteristics of ultrasonic piezoelectric osteotomy are selective cut of mineralized structure with less risk of vascular and nervous damage (microvibrations), intraoperative precision (thin cutting scalpel and no macrovibrations), blood free site (cavitation effect). In the authors' experience, piezoelectric scalpel, compared with saw and drill, enables them to reduce or avoid immediate complications of chin surgery, helping the surgeon to reach patients' satisfaction.

Implant rehabilitation of the edentulous jaws: Does tilting of posterior implants at an angle greater than 45° affect bone resorption and implant success?: A retrospective study.

PURPOSE: This study aimed to (1) investigate the success of posterior implants tilted >45° when 4 immediately loaded implants were used to support full-arch prostheses, eliminating any distal cantilever and (2) examine the effect on marginal bone loss (MBL) of different combinations of anterior multi-unit abutment (MUA) angles and posterior implant tilting angles. MATERIALS AND METHODS: Records of patients rehabilitated according to the Columbus Bridge Protocol were analyzed. Peri-implant bone levels (PBLs) and MBL were measured for each implant. The influence of posterior implant tilting angle on PBL, MBL, and implant and prosthetic success rate was investigated. The impact on the same endpoints of different anterior MUA angles, and different combinations of anterior MUA and tilted posterior implant angles was also examined. RESULTS: Records of 41 patients were analyzed, for a total of 46 complete rehabilitations, and 142 implants (52 anterior, 63 posterior tilted ≤45° [group 1], and 27 posterior tilted >45° [group 2]). No implants were lost during the follow-up (25.9 months), and no prosthetic complications were reported. Success rate for posterior implants was 100% in group 1 and 96.3% in group 2. Mean MBL differed significantly between the 2 groups (0.45 mm in group 1, 0.66 in group 2 [P = .04]), but not when the analysis was limited to implants in the same jaw. Implant tilting angle did not correlate with MBL and the MUA angle had no effect on bone resorption around posterior implants, neither in the sample as a whole nor in individual patients. CONCLUSIONS: Posterior implants tilted >45° to eliminate distal cantilever may be as safe as those tilted less in severely atrophic jaws rehabilitated with immediately loaded, full-arch prostheses supported on 4 implants. Further prospective studies on larger samples of patients and implants and with longer follow-up are needed to confirm these findings.

The influence of implant-abutment connection to peri-implant bone loss: A systematic review and meta-analysis.

PURPOSE: Different implant-abutment connections are available and it has been claimed they could have an effect on marginal bone loss. The aim of this review is to establish if implant connection configuration influences peri-implant bone loss (PBL) after functional loading. METHODS: A specific question was formulated according to the Population, Intervention, Control, and Outcome (PICO): Does the type of implant-abutment connection (external, internal, or conical) have an influence on peri-implant bone loss? A PubMed/MEDLINE electronic search was conducted to identify English language publications published in international journals during the last decade (from 2006 to 2016). The search was conducted by using the Medical Subject Headings (MeSH) keywords "dental implants OR dental abutment AND external connection OR internal connection OR conical connection OR Morse Taper." Selected studies were randomized clinical trials and prospective studies; in vitro studies, case reports and retrospective studies were excluded. Titles and abstracts and, in the second phase, full texts, were evaluated autonomously and in duplicate by two reviewers. RESULTS: A total of 1649 articles were found, but only 14 studies met the pre-established inclusion criteria and were considered suitable for meta-analytic analysis. The network meta-analysis (NMA) suggested a significant difference between the external and the conical connections; this was less evident for the internal and conical ones. Platform-switching (PS) seemed to positively affect bone levels, non-regarding the implant-connection it was applied to. CONCLUSIONS: Within the limitations of this systematic review, it can be concluded that crestal bone levels are better maintained in the short-medium term when internal kinds of interface are adopted. In particular, conical connections seem to be more advantageous, showing lower peri-implant bone loss, but further studies are necessary to investigate the efficacy of implant-abutment connection on stability of crestal bone levels.

Evaluation of Ultrashort and Longer Implants with Microrough Surfaces: Results of a 24- to 36-Month Prospective Study.

PURPOSE: The aim of this prospective study was to establish if ultrashort implants are a reliable therapeutic solution by evaluating their effect on mean crestal bone loss and assessing their survival and success rates. MATERIALS AND METHODS: Patients were treated using 6-, 9-, and 11-mm-long implants with sandblasted and acid-etched surfaces and fitted with fixed partial prostheses. Clinical and radiographic examinations were scheduled yearly. Data collected included the implant positioning site, implant length and diameter, peri-implant bone loss (PBL), and clinical and anatomical C/I ratios. RESULTS: One hundred eleven implants (6-mm-long, 30.6%) were positioned; two implants were lost before loading. During the 36-month followup, no other implants were lost (98.2% survival rate, 100% from loading), but four implants did not meet the criteria for success, due to excessive crestal bone loss, resulting in a 94.6% success rate, 96.3% from loading. Success rates and peri-implant bone loss were not significantly different among implants with different lengths. No correlation was observed between implant length and bone resorption. CONCLUSION: Six-millimeter-long implants did not show different results in comparison with 9- and 11-mm-long implants. They can be considered a reliable solution for implant prosthetic rehabilitation and a dependable and minimally invasive therapeutic option in areas showing severe bone resorption.

Primary and Secondary Stability of Implants in Postextraction and Healed Sites: A Randomized Controlled Clinical Trial.

PURPOSE: This randomized clinical trial aimed to investigate the relationships between insertion torque, implant stability quotient (ISQ), and crestal bone loss (CBL) of implants placed in fresh or 12-week healed extraction sites. MATERIALS AND METHODS: Forty patients were randomly assigned to one of two groups and had one implant placed immediately (test group, n = 20) or 12 weeks after extraction (control group, n = 20) at premolar or molar sites. For all implants, insertion torque and ISQ scores at insertion and loading were recorded. Patients were followed for up to 12 months. RESULTS: Implant success was 100% in both groups. No differences were observed concerning both ISQ at insertion and ISQ at loading. A stronger correlation was detected between ISQ at insertion and insertion torque in the postextractive group (R = 0.83), than in the delayed group (R = 0.39), while ISQ at loading and insertion torque showed no correlation. CBL at 12 months was significantly different between test (0.68 ± 0.43 mm) and control (0.40 ± 0.26 mm, P = .02) groups. CONCLUSION: Implant placement timing (immediate or delayed) may affect correlation between insertion torque and ISQ at insertion with ISQ at loading. While insertion torque influences ISQ at insertion, it does not affect ISQ at loading because of successful osseointegration. Postextraction and delayed implants seem to have similar ISQ at insertion and at loading, but different CBL after 12 months of follow-up because of postextraction bone remodeling.

Anatomical Remodeling of Buccal Bone Plate in 35 Premaxillary Post-Extraction Immediately Restored Single TPS Implants: 10-Year Radiographic Investigation.

PURPOSE: The anatomical remodeling technique (ART) was proposed to place postextraction implants with the aid of specific osteotomes. This study is a clinical and radiographic evaluation with 10-year follow-up of anterior postextraction single implants placed with the ART and immediately restored. MATERIALS AND METHODS: Thirty-five patients, with a hopeless tooth in the anterior maxilla, were included in the study and 35 implants were inserted according to the ART. Clinical and radiographic evaluations were performed at baseline (T0), after 6 (T1) and 14 months (T2), 4 years after surgery (T3) and every other year up to the 10-year follow-up (T4, T5, and T6). Implant success, survival, and failure rates were evaluated according to the International Congress of Oral Implantologists Pisa Consensus Conference criteria. RESULTS: Twenty-nine patients and 29 implants were available for the 10-year data analysis. After 10 years, the accumulated mean marginal bone loss was 2.69 ± 0.42 mm. The cumulative survival rate of the implants was 100%. CONCLUSIONS: Immediately loaded postextractive implants, placed according to the ART, have been proved to be a predictable method to rehabilitate single tooth in the anterior maxilla.

Peri-implant conditions around sintered porous-surfaced (SPS) implants. A 36-month prospective cohort study.

OBJECTIVES: The specific aim of this study was to assess sintered porous-surfaced (SPS) implant system from a biological point of view, through a prospective study of the health status and the evolution of the peri-implant tissues over time and analysis of the changes observed in the various peri-implant parameters. MATERIAL AND METHODS: Hundred and fifty-one patients were treated consecutively from 2005 to 2007 using 280 SPS implants, which were restored with a single crown or a partial fixed denture. To accurately monitor the health and biological evolution of peri-implant soft and hard tissues, a number of clinical parameters were adopted, such as the modified Plaque Index (mPI), the modified sulcus Bleeding Index (mBI), Peri-implant Probing Depth (PPD), and Crestal Bone Level (CBL). Clinical and radiographic examinations were scheduled over a 36-month follow-up of functional loading according to a well-established protocol generally applied to determine implant success rates and Peri-implant Bone Loss (PBL). Statistical analysis was used to determine any significant differences or correlations (P = 0.05). RESULTS: A total of 259 SPS implants in 136 patients were followed up for 36 months. According to Buser's success criteria, the overall implant-based success rate was 98.1% and the mean PBL was 0.48 ± 0.29 mm. MBI and mPI mean values showed statistically significant differences between baseline and follow-up analyses (P < 0.001). No statistically significant differences in mean PPD values were found between baseline and control analyses (P = 0.060). CONCLUSION: This prospective cohort study revealed that the biological behavior of SPS implant system was characterized by high tissue stability during the observation period, both as regards soft and hard tissues. In particular, the crestal bone remodeling pattern was very similar to that reported in other studies, confirming that the bone loss around SPS implants, at least at 36 months, seems to be predictable.

Immediate function of partial fixed rehabilitation with axial and tilted implants having intrasinus insertion.

Implant-supported rehabilitation of the posterior maxilla could be challenging because hyperpneumatization of the maxillary sinus might reduce the bone height. In this study, the authors report preliminary results of a new treatment modality for the partial fixed rehabilitation of posterior maxilla with immediate function by using 1 anterior axial implant and 1 posterior tilted implant with intrasinus mesial insertion. From 2009 to 2011, 10 patients (6 women and 4 men) with missing upper premolars and molars were recruited and treated according to this protocol. Each patient received a partial fixed bridge supported by 1 axial anterior implant and 1 posterior implant placed with a 30-degree mesial inclination and intrasinus insertion. Autologous bone was positioned to fill the maxillary sinus cavity and to cover the exposed implant surface after elevation of the anterior sinus membrane. A prosthesis with immediate function was positioned within 3 hours, whereas a CAD/CAM final restoration was delivered 6 months later. Follow-ups at 6 and 12 months, and then annually, were scheduled. At each follow-up, plaque level and bleeding scores were assessed, and radiographic evaluation of marginal bone level change was performed at 1 year. The patients were followed up for a mean of 50 months (range, 42-57 mo). No implants were lost, and all prostheses were stable and functional, reporting 100% of implant and prosthetic success rates. After 1 year, bone loss had a mean (SD) of 1.0 (0.4) and 0.9 (0.5) mm for axial and tilted implants, respectively, with no statistically significant differences between them (P > 0.05). The preliminary results suggest that this approach could allow the rehabilitation of posterior maxilla with immediate function in case of reduced bone volume, representing an alternative technique to bone grafting, short implants, and zygomatic or pterygoid implants.

Influence of crown-implant ratio on implant success rates and crestal bone levels: a 36-month follow-up prospective study.

OBJECTIVES: The aim of this prospective study was to determine how the crown-implant ratio (C/I ratio) influences crestal bone loss and implant success rates after a 3-year follow-up, using implants with a sintered porous surface (SPS). MATERIALS AND METHODS: On the basis of preestablished inclusion and exclusion criteria, 151 of a cohort of 160 patients with single or partial edentulism were selected as eligible for the study. The 151 patients were treated consecutively from 2005 to 2007 using 280 SPS implants, which were restored with a single crown or a partial fixed denture. The data collection included both clinical and anatomical C/I ratios; other implant prosthetic factors were also recorded. Implants were divided into three groups according to the C/I ratio. Clinical and radiographic examinations were scheduled over a 36-month follow-up of functional loading according to a well-established protocol generally applied to determine implant success rates and crestal bone levels. Statistical analysis was used to determine any significant differences or correlations (P = 0.05). RESULTS: A total of 259 SPS implants in 136 patients were followed up for 36 months. According to the success criteria, the overall implant-based success rate was 98.1%, and the mean peri-implant bone loss (PBL) was 0.48 ± 0.29 mm. Statistical analysis revealed significant correlation between implant success rate and C/I ratio (P < 0.05) and between PBL and C/I ratio (P < 0.05). The critical threshold value of the anatomical and clinical C/I ratio for avoiding excessive bone loss or implant failure was 3.10 and 3.40. CONCLUSION: This prospective cohort study revealed that SPS implants offer a predictable solution for implant prosthetic rehabilitation in patients with edentulism characterized by different alveolar bone atrophy. From the biomechanical point of view, the C/I ratio would appear to be the main parameter capable of influencing implant success and crestal bone loss. Consequently, it is important not to exceed the threshold values in order to avoid excessive stress at the bone-implant interface capable of resulting in excessive crestal bone loss or implant failure.