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Background: A study was made of the dimensional changes in free epithelialized gingival/mucosal grafts (FEGs) used to augment keratinized tissue (KT) at tooth and implant sites, and of the confounders influencing the dynamic changes over 6 months of follow-up.Methods: A prospective cohort interventional study was made of implant and tooth sites needing KT augmentation by means of an apically positioned flap and FEG. Six intraoperative variables were recorded at baseline (T0). In addition, graft width (GW), graft length (GL), and graft dimension (GD) were assessed at 3 weeks (T1), 3 months (T2), and 6 months of follow-up (T3). Univariate and multivariate analyses were performed to explore associations between the demographic and intraoperative variables and the outcomes over the study period.Results: Based upon an a priori power sample size calculation, a total of 56 consecutive patients were recruited, of which 52 were available for assessment. A total of 73 graft units were included in 122 sites. At T3, the mean change in GD in FEG was 40.21%. In particular, the mean changes in GL and GW were 12.13% and 33.06%, respectively. Statistically significant changes in GD were recorded from T0 to T1 (P < 0.0005) and from T1 to T2 (P < 0.0005), but not from T2 to T3 (P = 0.13). The change in GD at T3 was 33.26% at tooth and 43.11% at implant site level (P = 0.01). Age and GW assessed at T0 proved to be related to the changes in GD and GW in the univariate and multivariate analyses. The univariate analysis showed the avascular area (AA) to be related to the changes in GD and GW at the implant sites, whereas graft thickness (GT) was associated to changes in GD and GW at the tooth sites in the univariate and multivariate analyses.Conclusion: Free epithelialized grafts are exposed to dimensional changes that result in a reduction of approximately 40% of the original graft dimension-the changes being approximately 10% greater at the implant sites than at the tooth sites (NCT04410614). [ABSTRACT FROM AUTHOR]

This investigation was designed and implemented as a single-center, prospective study to evaluate the clinical response to the Laser-Assisted New Attachment Procedure (LANAP). Eight patients with advanced periodontitis were enrolled and treated with full-mouth LANAP therapy and monitored for 9 months. Fullmouth clinical measurements, including clinical attachment level (CAL), probing depth (PD), and recession, were provided at baseline and after 9 months of healing by a single calibrated examiner, including a total of 930 sites and 444 sites with initial PD equal to or greater than 5 mm. Clinical results for the 930 sites measured pre- and postoperatively revealed that mean PD was reduced from 4.62 ± 2.29 mm to 3.14 ± 1.48 mm after 9 months (P < .05). CAL decreased from 5.58 ± 2.76 mm to 4.66 ± 2.10 mm (P < .05) and recession increased from 0.86 ± 1.31 mm to 1.52 ± 1.62 after 9 months (P < .05). For the subset of 444 sites with initial PD greater than or equal to 5 mm, the PD decreased from 6.50 ± 2.07 mm to 3.92 ± 1.54 mm (P < .05) and CAL decreased from 7.42 ± 2.70 mm to 5.78 ± 2.06 mm (P < .05). As demonstrated by the clinical evaluation, the majority of treated sites demonstrated clinical improvement. LANAP therapy should be further investigated with long-term clinical trials to compare the stability of clinical results with conventional therapy. [ABSTRACT FROM AUTHOR]

Aim To test whether an equine bone substitute block used for guided bone regeneration ( GBR) of peri-implant defects renders different results from bovine block or particulated bone substitutes regarding the dimensions of the augmented ridge and the amount of new bone. Material and methods Mandibular premolars and molars were extracted in eight dogs. After 4 months, four semi-saddle bone defects were created in each mandible and one titanium implant was inserted into every site. Bone augmentation by GBR was attempted using the following randomly assigned modalities: (i) particulated deproteinized bovine bone mineral ( DBBM) + a collagen membrane ( CM), (ii) block DBBM + CM, (iii) equine bone substitute block + CM, and (iv) empty controls. After 4 months, one central and two lateral sections of each site were prepared. Descriptive histological and histomorphometrical assessments were performed evaluating the augmented area ( AA) within the former bone defect, the area of mineralized tissue ( MT), non-mineralized tissue ( NMT), and residual bone substitute ( BS) within AA, the horizontal thicknesses of the augmented region ( HTaugm) and of the mucosa ( HTmucosa). Results At the central sections, AA measured 11.2 ± 3.3 mm2 for the equine block, 9.5 ± 2.6 mm2 for DBBM block, 7.9 ± 4.8 mm2 for particulated DBBM, and 2.4 ± 2.1 mm2 for the empty control. All GBR groups rendered significantly higher values of AA in comparison with control ( P ≤ 0.05). The differences in AA between GBR groups did not reach statistical significance ( P > 0.05). The equine block rendered the highest values in HTaugm, although only the differences between equine block and control as well as equine block and DBBM block were statistically significant ( P ≤ 0.05). With respect to HTmucosa, all GBR groups reached significantly higher values compared to control ( P ≤ 0.05). The equine block revealed the most pronounced signs of graft degradation. Conclusions Guided bone regeneration lead to higher ridge dimensions and thicker covering mucosa than empty controls. The equine block with CM resulted in the most favorable outcomes regarding the maintenance of ridge contour. There were no significant differences regarding amount of new bone between GBR treatments. [ABSTRACT FROM AUTHOR]

Objective To evaluate the volumetric changes occurring from prosthesis insertion to the 1-year follow-up (FU) using one- and two-piece dental implants. Methods Sixty patients were randomly assigned to receive one-piece or two-piece implants. Casts were obtained at baseline (insertion of final reconstruction) and at 1 year of loading. Finally, 33 pairs of casts ( BRA = 18, STM = 15) were deemed appropriate for volumetric analysis of the peri-implant tissues. If the patients had more than one implant, one was randomly selected for analysis. Casts were scanned to obtain stereolithography ( STL) files. Baseline and 1-year FU digital models were superimposed with an image analysis program. Linear and volumetric measurements were performed including (i) crown height changes (CHCs), (ii) volumetric changes, and (iii) changes in tissue thickness at three levels below the mucosal margin on the buccal side of the implants (at 1,3, and 5 mm). The Mann-Whitney U-test and the paired t-test were used to analyze the data between the two groups using the patient as the unit of analysis. Results No significant baseline differences were observed between the one- and two-piece groups for the linear measurements. The mean CHCs in the two-piece group amounted to 0.02 mm ( SD ± 0.32), whereas the one-piece group exhibited a change of −0.17 mm (±0.57). The mean volume changes (VCs) were −0.12 mm (±0.27) (two-piece group) and −0.03 mm (±0.29) (one-piece group). With regard to the changes in tissue thickness, the two-piece group presented a change of −0.15 mm (±0.20) at 1 mm, −0.06 mm (±0.20) at 3 mm, and −0.2 mm (±0.51) at 5 mm. The respective values for the one-piece group were −0.03 mm (±0.35), 0.01 mm (±0.28), and −0.01 mm (±0.51) at the three levels. None of the differences in linear measurements between baseline and the 1-year FU reached significance. Positive correlations were seen for tissue thickness changes at 1 and 3 mm for both groups ( P < 0.05). Significant positive correlations were found for VCs and tissue thickness at 1 mm for the two-piece group and for VCs and tissue thickness at 1,3, and 5 mm for the one-piece group ( P < 0.05). Conclusion Within the first year of loading, minimal changes occur with regard to tissue thickness, crown height, and facial volume for both implant types. [ABSTRACT FROM AUTHOR]

Objectives The aim was to test whether or not the marginal bone-level alterations of loaded zirconia implants are similar to the bone-level alterations of a grade 4 titanium one-piece dental implant. Materials and methods In six dogs, all premolars and the first molars were extracted in the mandible. Four months later, three zirconia implants ( BPI, VC, ZD) and a control titanium one-piece ( STM) implant were randomly placed in each hemimandible and left for transmucosal healing (baseline). Six months later, CAD/ CAM crowns were cemented. Sacrifice was scheduled at 6-month postloading. Digital X-rays were taken at implant placement, crowns insertion, and sacrifice. Marginal bone-level alterations were calculated, and intra- and intergroup comparisons performed adjusted by confounding factors. Results Implants were successfully placed. Until crown insertion, two implants were fractured (one VC, one ZD). At sacrifice, 5 more implants were (partly) fractured (one BPI, four ZD), and one lost osseointegration ( VC). No decementation of crowns occurred. All implant systems demonstrated a statistically significant (except VC) loss of marginal bone between baseline and crown insertion ranging from 0.29 mm ( VC; P = 0.116) to 0.80 mm ( ZD; P = 0.013). The estimated marginal bone loss between baseline and 6 months of loading ranged between 0.19 mm ( BPI) and 1.11 mm ( VC), being statistically significant for STM and VC only ( P < 0.05). The changes in marginal bone levels were statistically significantly different between zirconia implants and control implants ( STM vs. BPI P = 0.007; vs. VC P = 0.001; vs. ZD P = 0.011). Conclusions Zirconia implants were more prone to fracture prior to and after loading with implant-supported crowns compared to titanium implants. Individual differences and variability in the extent of the bone-level changes during the 12-month study period were found between the different implant types and materials. [ABSTRACT FROM AUTHOR]

Objective To compare the clinical and radiographic outcomes of implants and implant-supported reconstructions using a 1-piece ( STM) and a 2-piece ( BRA) dental implant system. Material and methods Sixty patients were randomly assigned to receive STM or BRA implants. The implants restored with fixed or removable prostheses. Baseline measurements (day of loading) and 1-year measurements included demographic and radiological parameters with details of the surgical procedures, type of prosthesis, survival of implants, and marginal bone-level changes. The Mann-Whitney U-test and the paired t-test were used to analyze the data between the two groups and within the groups within 1 year on an implant- and patient-based level. Results In all 60 patients, implants were placed and supported 65 final reconstructions (33 BRA, 32 STM). One implant was lost in the STM group at 9 months (98.5% survival rate), none were lost in the BRA group (100%). On the implant level, the median marginal bone levels were −1.02 mm (interquartile range ( IQR) 0.41 mm) at baseline and −1.08 mm (0.59 mm) 1 year later ( BRA) and −0.51 mm (0.93 mm) and −0.75 mm (1.14 mm) ( STM). The patient level values were −0.98 mm (0.47 mm) at baseline and −1.10 mm (0.71 mm) 1 year later ( BRA) and −0.43 mm (0.59 mm) and −0.71 mm (0.97 mm) ( STM). The differences between the two groups at both time-points were statistically significant in the patient-level analysis with higher bone levels for the STM group ( P < 0.05). The changes in mean marginal bone levels on the implant level amounted to −0.05 mm ( SD±0.32 mm) ( BRA) and to −0.27 mm (±0.52 mm) ( STM). Patient-level values were −0.06 mm (± 0.37 mm) ( BRA) and −0.25 mm (±0.35 mm) ( STM). These differences between the groups reached statistical significance on the patient level with less bone loss in the BRA group ( P < 0.05). Conclusions Within the first year of functional loading, high survival rates and minimal changes of marginal bone levels were found for both implant systems used. [ABSTRACT FROM AUTHOR]

Peri-implantitis is an infectious disease that leads to progressive bone loss. Surgical therapy has been advocated as a way of halting its progression and re-establishing peri-implant health. One of the most challenging but crucial tasks in the management of peri-implantitis is biofilm removal to achieve reosseointegration and promote the reduction of peri-implant pockets. A wide variety of strategies have been used for implant surface decontamination. Mechanical means have been demonstrated to be effective in eliminating calculus deposits and residual debris; however, the presence of undercuts and the grooves and porosities along the roughened implant surface make it difficult to achieve an aseptic surface. In conjunction with mechanical measures, use of chemical adjuncts has been advocated to dilute bacterial concentrations, destroy the bacteria's organic components and eliminate endotoxins. Pharmacological adjuncts have also been recommended to diminish the bacterial load. Other strategies, such as use of lasers, implantoplasty and electrolysis, have been suggested for implant surface decontamination to promote predictable clinical and radiographic outcomes.