International Journal of Periodontics & Restorative Dentistry, 01/2014

This multicenter case series introduces an innovative ultrasonic implant site preparation (UISP) technique as an alternative to the use of traditional rotary instruments. A total of 3,579 implants were inserted in 1,885 subjects, and the sites were prepared using a specific ultrasonic device with a 1- to 3-year follow-up. No surgical complications related to the UISP protocol were reported for any of the implant sites. Seventy-eight implants (59 maxillary, 19 mandibular) failed within 5 months of insertion, for an overall osseointegration percentage of 97.82% (97.14% maxilla, 98.75% mandible). Three maxillary implants failed after 3 years of loading, with an overall implant survival rate of 97.74% (96.99% maxilla, 98.75% mandible). (Int J Periodontics Restorative Dent 2014;34:11-18. doi: 10.11607/prd.1860)

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. (Int J Periodontics Restorative Dent 2014;34:21-27. doi: 10.11607/prd.1848)

The aim of this study was to test whether veneering of the submucosal part of zirconia abutments using pink veneering ceramic positively influences the color of the peri-implant mucosa. Single-tooth implants were restored with either white zirconia abutments (control group) or pink-veneered zirconia abutments and allceramic crowns. Esthetic outcome measurements included a spectrophotometric evaluation of the peri-implant mucosal color. Test and control groups induced a visible discoloration of the peri-implant mucosa after the insertion of the abutments and following cementation of the crowns compared to natural teeth. The calculated color differences were above the clinically visible threshold value and were more favorable for the control group, although not statistically significant. It is concluded that veneering of zirconia abutments with pink veneering ceramic failed to positively influence the esthetic outcome, mostly due to a decrease of the brightness compared with the control group. (Int J Periodontics Restorative Dent 2014;34:29-37. doi: 10.11607/prd.1870)

This investigation was designed to evaluate the histologic healing pattern of two Miller Class III recession defects associated with noncarious cervical lesions (NCCLs) treated with a connective tissue graft (CTG) and coronally advance flap (CAF). One patient presenting with two teeth predetermined to be surgically extracted was enrolled and consented to treatment. One month after phase I treatment, a full-thickness flap was reflected and the NCCLs treated with a compomer restoration; at the same time, a CTG was harvested from the palate and positioned over the compomer restoration. The flap was then coronally repositioned. After 4 months of healing, an en bloc biopsy extraction of the two teeth was executed. The teeth were analyzed histologically to assess the periodontal wound healing. A long junctional epithelial attachment was noted throughout the major portion of the restored surface. Only minimal signs of connective adhesion and new bone formation could be seen in the apical portion of the restored area, without signs of root resorption or ankylosis. This report provides evidence that the presence of a compomer restoration allowed the formation of a long juctional epithelium after CTG and CAF treatment. (Int J Periodontics Restorative Dent 2014;34:39-45. doi: 10.11607/prd.1921)

Twelve implants with peri-implantitis underwent reentry flap surgery in five patients 6 to 96 months postregenerative surgery. This was necessary for additional treatment or new treatment of adjacent or other implants in close proximity to the original implant. Clinical measurements of the original depth of bone lesions ranged from 3 to 12 mm. Bone fill occurred around all implants and ranged from 2 to 9 mm, representing 40% to 100% of the original defect depth. These direct bony measurements support radiographic and sounding data in a previous report that recorded a mean of over 3 mm of bone fill in the defects treated with the specific regenerative approach used in this study. The results of this clinical series are encouraging; however, histologic research is necessary to determine if reosseointegration occurred, with direct visual evidence suggesting new bone formation, and more multicenter studies are needed to verify the results. (Int J Periodontics Restorative Dent 2014;34:47-59. doi: 10.11607/prd.1904)

The use of immediate placement and loading protocols in implant dentistry has increased during the past several years. However, limited information related to the response of the osseous architecture has been reported. The purpose of this study was to evaluate the fate of the buccal alveolar plate with cone beam computed tomography (CBCT) following lingualized placement of implants into fresh extraction sockets using a flapless surgical approach and immediate nonocclusal loading. A total of 14 patients who required extraction of a single maxillary incisor were selected for this study. CBCT was performed preextraction, at the time of implant placement, and 6 months following implant surgery. The results of this study indicate that resorption of the buccal alveolar plate was not significant. It was therefore concluded that with strict patient selection and appropriate technique, predictable healing can be achieved with lingualized implant placement into fresh extraction sockets and immediate loading. (Int J Periodontics Restorative Dent 2014;34:61-68. doi: 10.11607/prd.1807)

This study aimed to examine the combination of mineral trioxide aggregate (MTA) and subepithelial connective tissue grafts to treat esthetic deficiencies caused by iatrogenic tooth perforations. Three patients were treated, and clinical and histologic documentation was obtained. Connective tissue grafts were performed following standard techniques after application of MTA to seal the root perforations. Complete root coverage was obtained, significantly improving the esthetic outcomes. Histologic analysis showed the long junctional epithelium in intimate contact with the root surface. It appeared to form coronal to the perforation and extended apical to the MTA. Based on the limitations of this clinical and histologic observation, it can be concluded that MTA in conjunction with connective tissue grafts could be considered for treatment of esthetic deficiencies associated with iatrogenic tooth perforations. (Int J Periodontics Restorative Dent 2014;34:71-77. doi: 10.11607/prd.1674)

The purpose of this study was to evaluate the influence of a Laser-Lok microtexturing surface on clinical attachment level and crestal bone remodeling around immediately functionally loaded implants in single-tooth replacement. Seventy-seven patients were included in a prospective, randomized study and divided into two groups. Group 1 (control) consisted of non-Laser-Lok type implants (n = 39), while in group 2 (test), Laser-Lok type implants were used (n = 39). Crestal bone loss (CBL) and clinical parameters including clinical attachment level (CAL), Plaque Index (PI), and bleeding on probing were recorded at baseline examinations and at 6, 12, and 24 months after loading with the final restoration. One implant was lost in the control group and one in the test group, giving a total survival rate of 96.1% after 2 years. PI and BOP outcomes were similar for both implant types without statistical differences. A mean CAL loss of 1.10 ± 0.51 mm was observed during the first 2 years in group 1, while the mean CAL loss observed in group 2 was 0.56 ± 0.33 mm. Radiographically, group 1 implants showed a mean crestal bone loss of 1.07 ± 0.30 mm compared with 0.49 ± 0.34 mm for group 2. The type of implant did not influence the survival rate, whereas Laser-Lok implants resulted in greater CAL and in shallower radiographic peri-implant CBL than non-Laser-Lok implants. (Int J Periodontics Restorative Dent 2014;34:79-89. doi: 10.11607/prd.1747)

During host interaction against oral biofilm, matrix metalloproteinase-8 (MMP-8) is activated, leading to collagenolytic destruction of host tissues. In periimplantitis patients, the active form of MMP-8 is elevated in peri-implant sulcus fluid (PISF). In this study, MMP-8 in PISF from titanium abutments and those coated with zirconium nitride (ZrN) was compared in vivo in a split-mouth design in 60 patients at 6 weeks, 6 months, and 12 months after prosthetic restoration. At each time point, MMP-8 values in PISF differed significantly between titanium and ZrN abutment surfaces. For example, mean MMP-8 values reached 10 to 12 ng/mL in titanium and only 6.6 to 7.5 ng/mL with ZrN. Similarly, the 75th percentile MMP-8 concentrations were 12 to 15 ng/mL and 8 to 9 ng/mL for titanium and ZrN, respectively. Based on this finding, ZrN-coated abutments seem to exert a beneficial effect regarding collagenolytic tissue destruction driven by MMP-8 in situ. (Int J Periodontics Restorative Dent 2014;34:91-95. doi: 10.11607/prd.1504)

Twenty-four teeth were extracted en bloc with the marginal periodontal structures and processed for histologic purposes. Measurements were taken from the top of the gingival margin to the apical limit of the junctional epithelium (GM-JE), from the apical limit of the junctional epithelium to the top of the alveolar bone crest (JE-AB), and from the top of the gingival margin to the top of the alveolar bone crest (GM-AB). Data were histometrically analyzed. This first clinical human study demonstrated mean measurements of 1.58 ± 0.41 mm for GM-JE, 1.18 ± 0.42 mm for JE-AB, and 2.75 ± 0.59 mm for GM-AB. (Int J Periodontics Restorative Dent 2014;34:97-102. doi: 10.11607/prd.1353)

This study reports the incidence of complications and sinus membrane perforations when using sonic instruments to prepare the lateral window osteotomy for maxillary sinus augmentation. The charts of 33 consecutive patients (40 sinuses) were reviewed. Sinus membrane perforations were reported in 7 cases (17.5% of procedures), with 3 perforations occurring during preparation of the osteotomy window (7.5% of procedures). Postoperatively, 2 cases of sinus infection (5%) and 2 cases of flap dehiscence (5%) were recorded. This study demonstrates that elevation of the sinus floor with a combination of hand and sonic instruments is feasible and safe, with a limited incidence of complications. (Int J Periodontics Restorative Dent 2014;34:105-112. doi: 10.11607/prd.1387)

The aims of this study were to measure the thickness of the palatal masticatory mucosa and determine its histologic characteristics with reference to autogenous grafting. Thirty-two fully dentate, cadaver hemimaxillae were examined (from 13 men and 3 women; mean age, 57.1 years). The thickness of the palatal masticatory mucosa was assessed at 24 standard measurement points on the sectioned specimens after decalcification, and then the specimens were processed for embedding in paraffin, sectioned, and stained with hematoxylin and eosin. The thickness of the palatal masticatory mucosa varied by tooth site as follows: 3.55 ± 1.09 mm (mean ± SD; distal canine), 3.51 ± 0.99 mm (distal first premolar), 3.28 ± 1.07 mm (distal second premolar), 2.83 ± 1.00 mm (midline first molar), 2.92 ± 1.03 mm (distal first molar), and 3.15 ± 1.66 mm (distal second molar). The thickness also varied according to distance from the cementoenamel junction (CEJ): 2.35 ± 0.79 mm at 3 mm below the CEJ, 2.65 ± 0.77 mm at 6 mm, 3.52 ± 0.94 mm at 9 mm, and 4.29 ± 1.14 mm at 12 mm. Histologic analysis showed that the thickness of the lamina propria decreased toward the posterior palatal area and midpalatal suture, while that of the submucosa increased. These results suggest that the most appropriate donor site for gingival autogenous grafting is the region 3 to 9 mm below the CEJ between the distal surface of the canine and the midline surface of the first molar. (Int J Periodontics Restorative Dent 2014;34:115-121. doi: 10.11607/prd.1530)

In clinical situations where the presence of severe horizontal ridge deficiencies precludes simultaneous implant placement and bone augmentation, a staged approach may be desirable to allow optimal implant placement. Numerous therapeutic options are available for the treatment of the horizontally deficient ridge. With advances in tissue engineering, the use of growth factors can significantly improve wound healing with more rapid bone formation and maturation. These case reports demonstrate a technique that enhances the predictability of horizontal bone gain with reduced surgical trauma and postoperative complications. Recombinant human platelet-derived growth factor BB (rhPDGF-BB) in combination with particulate allograft is used to stimulate the proliferation and migration of osteogenic cells. A ridge split technique with vertical bone incisions allows expansion and mobilization of the buccal plate, creating a space that will contain the particulate graft material. Decortication of the mobilized buccal plate will create pathways to allow cellular and vascular access for enhanced maturation. Additional graft material is placed lateral to the mobilized buccal plate to increase apical ridge width. The use of piezoelectric surgery enables a precise crestal bony incision in severely deficient ridge widths and aids in faster wound healing. This study discusses the technique and the recommended therapeutic considerations to ensure predictable regeneration of adequate bone for optimal implant placement in horizontally deficient ridges. (Int J Periodontics Restorative Dent 2014;34:123-130. doi: 10.11607/prd.1633)

A number of diagnostic and management challenges exist for achieving complete regeneration of large through-and-through periapical lesions. An unfavorable endodontic outcome may occur as a result of uncontrolled infection or unpredictable bone healing. This article presents a case with a 15 × 15-mm through-and-through periapical lesion and persistent gingival swelling. Endodontic microsurgery and guided tissue regeneration were performed using a resorbable membrane and osseous substitute. A 2-year postoperative radiograph revealed complete resolution of the periapical radiolucency. Seven-year clinical and radiographic follow-up showed that the tooth was asymptomatic and a long-term successful outcome had been maintained. (Int J Periodontics Restorative Dent 2014;34:e1-e8. doi: 10.11607/prd.1472)

Direct laser metal forming (DLMF) is a procedure in which a high-power laser beam is directed on a metal powder bed and programmed to fuse particles according to a computer-aided design file, thus generating a thin metal layer. With DLMF, it is now possible to fabricate dental implants with a superficial porous surface. The aim of the present study was to evaluate the peri-implant soft tissues around human-retrieved DLMF dental implants. Collagen fibers, in the form of bundles, were oriented perpendicularly to a distance of 100 μm from the surface, where they became parallel, running in several directions. In some portions, only a few collagen fiber bundles appeared to be oriented perpendicularly or obliquely to the plane of the section. Collagen fibers appeared to form a dense chaotic threedimensional network running in different, more or less parallel directions to the surface. Under scanning electron microscopy, an intimate contact of the fibrous matrix with the implant surface was evident, and some collagen bundles could be seen to bind directly to the metal surface. By changing the surface microtexture, it was possible to change the response of the peri-implant soft tissues. (Int J Periodontics Restorative Dent 2014;34:e9-e17. doi: 10.116047/prd.1213)

The objective of this study was to biomechanically and histologically assess the stability and integration of titanium implants that include hydroxyapatite based submicron-scale features. Thirty-four 3.4 mm × 6.5 mm implants, equally split between test (grit blasted, etched, and submicron scale deposition) and control (grit blasted and etched) groups, were placed in the tibiae of New Zealand White rabbits. At 3-weeks follow-up, the group with the submicron deposition showed significantly improved bone response compared with the control group. The test group required higher removal torque values, with its post-torque histology demonstrating both enhanced bone formation and an intact interface indicative of a robust bone-to-implant bond. (Int J Periodontics Restorative Dent 2013;33:e18-e25. doi: 10.11607/prd.1685)

This study evaluated the effect of prophylactic polishing pastes on the roughness and translucency of lithium disilicate ceramic. Sixty specimens were obtained from e.max CAD blocks. After ground finishing, each specimen was glazed and randomly divided into one of five groups, including one control group. They were then polished with one of four types of prophylactic paste. Group A: Nupro coarse, group B: Nupro medium, group C: Nupro fine, and group D: Cleanic. Specimens were polished with these pastes for 2 minutes with a prophy cup mounted on the handpiece under a constant load of 400 gr at 3,000 rpm. After polishing, the specimens were cleaned ultrasonically in distilled water and dried. The surface roughness (Ra, μm) was then measured using a surface profilometer. The translucency analysis was carried out on the glazed (control group) and polished specimens using a dental spectrophotometer. For each specimen, measurements were made once with a white and once with a black background. Group A showed significantly less surface roughness compared with the control group and groups B, C, and D. The control group showed significantly higher translucency compared with the other groups (P .05). Despite the good abrasion resistance of e.max CAD lithium disilicate ceramic, prophylactic pastes produced a reduction in translucency. Surface roughness varied depending on the paste used. Polishing procedures should be carried out with caution to not compromise the esthetics achieved with prosthetic restorations. (Int J Periodontics Restorative Dent 2014;34:e26-e29. doi: 10.11607/prd.1155)