International Journal of Periodontics & Restorative Dentistry, 03/2017

This study presents a novel technique based on guided bone regeneration and onlay grafts for three-dimensional bone augmentation. This two-stage technique uses an autogenous cortical bone plate and collagen membranes to form a barrier containing a mixture of deproteinized bovine bone matrix, autologous blood, and bone grafted from intraoral sites. Five patients were treated. At 6 months postsurgery, a mean increase in bone volume of 1,062 mm3 was shown. Mean maximum linear augmentation was 3.65 mm. Histologic analysis of the regenerated areas revealed the presence of compact newly formed bone with no sign of inflammation. A total of 13 implants were placed. The patients were satisfied, and complications were not observed.

The purpose of the current study was to determine the survival rates and to measure marginal bone changes and peri-implant conditions 8.5 years after placement of one-piece implants with an anodically oxidized surface (AOS). A total of 52 subjects who received a one-piece implant with an AOS using a flapless or flap protocol and completed a previous randomized clinical trial were contacted for a recall visit 8.5 years after implant placement (T8.5). Implant success and survival rates, probing pocket depth (PPD), presence of bleeding on probing (BoP), papilla level, and incidence of complications and peri-implant disease were assessed by a single, blinded examiner. A second blinded examiner evaluated marginal bone level changes. Results for 8.5 years were compared to those at the time of implant placement, implant loading (0.5 year), and 1 and 1.5 years follow-up. The results based on 28 patients who attended the follow-up visit (half had flapless and half a flap protocol) showed a 100% implant survival rate and a 96.4% implant success rate 8.5 years after implant placement using one-piece implants, with no difference in survival and success rates between the flapless and the flap protocol. During the same follow-up period, a significant increase in crestal bone height from 1.5 to 8.5 years was observed. Analysis suggested decreasing mean levels of bone loss with time (P .001). Moreover, there was 0.8 to 1.0 mm of bone loss through year 1.5, which decreased to 0.3 mm at 8.5 years (P .05). There was no statistically significant difference in PPD or BOP over time. Similar mean levels of PPD were found in flap and flapless groups (mean [SD] = 2.4 [0.3] and 2.2 [0.4] mm, respectively [P = .18]), as well as similar rates of BOP (22.8% vs 17.9%, respectively). Papilla levels increased during the first year after implant loading. However, there was little additional change between 1.5 and 8.5 years. A total of eight fractured porcelain crowns and three crown loosenings were reported. One-piece implants with an AOS showed high survival rates and stable marginal bone and periimplant soft tissue levels regardless of whether a flapless or flap protocol was used.

Three patients with multiple Miller Class III recession defects with substantial bone loss were treated with hard tissue augmentation with the goal to prevent future recessions. The surgery involved a full-thickness mucoperiosteal coronally advanced flap, bone grafting, and primary flap closure. Freeze-dried bone allograft (FDBA) in combination with plasma rich in growth factors (PRGF) was grafted during the procedure. After more than 6 months, the treated sites showed soft tissue maturation and esthetic tissue blending. Clinically, an increase in convexity of alveolar ridge and soft tissue was observed, as well as a marked reduction in recession depth and gain in width of keratinized mucosa. Cone beam computed tomography showed a gain in buccal bone thickness. The use of FDBA in combination with PRGF appears to have potential for the treatment of Miller Class III defects by providing improved hard and soft tissue profiles.

Mandibular ridge augmentation via guided bone regeneration in the atrophic mandible is considered one of the most challenging scenarios for implantsupported oral rehabilitation. Uneventful wound healing has clearly demonstrated its impact on the final regenerative outcome. Soft tissue management must be precise and adequate to attain flap-free wound closure. Accordingly, it demands exhaustive insight and expertise to avoid damaging the neighboring structures. The cadaver study described herein discusses the mandibular morphologic landmarks (ie, musculature, vascularization, innervation, and salivary glands) necessary to safely perform regenerative procedures in the atrophic mandibular ridge, such as vertical ridge augmentation and dental implant surgery. The potential intraoperative complications are presented, as well as clinical implications of which the clinician must be aware to prevent adverse surgical events during regenerative surgery and implant placement in this anatomical region.

Bone deficiencies in the jaws of edentulous patients limit the possibility of successful placement and osseointegration of endosseous implants. Bone resorption is defined as a vertical and horizontal loss of quality and quantity in the residual bone ridges; lack of bone structure requires bone grafting procedures to enable implant placement and to improve the function, predictability, and longevity of implants. The objective of this case study was to demonstrate the feasibility of a novel cell therapy treatment for localized jaw bone defects with tissue repair cells composed of a mixture of bone marrow-derived cells, including CD90+ mesenchymal stem cells and CD105+ monocytes/macrophages, and xenograft blocks, in what would be a safe and efficacious approach to the regeneration of localized craniofacial bone defects. The use of stem cells represents an alternative that could offer improved results, better quality histologically, and greater quantity in millimeters of tissue in bone regeneration.

The complete absence of keratinized attached gingiva on the buccal surface of a tooth can make the area more susceptible to gingival recession. The modified apically repositioned flap (MARF) technique is an effective procedure to increase the dimensions of attached gingiva in areas that present with some existing keratinized tissue. The objective of this case report is to present long-term clinical and histologic evidence that the MARF technique can be used to create attached gingiva in areas that lack keratinized tissue.

The aim of this study was to evaluate the accuracy of bone sounding (BS) in assessing the facial osseous-gingival tissue relationship (FOGTR) of failing maxillary anterior teeth. Dental records of patients who received immediate implant placement (IIP) at the maxillary anterior area were screened. Mid- FOGTR prior to extraction (BS), and immediately after flapless extraction (direct bone level [DBL] measurement) were analyzed. A total of 160 patients with 190 maxillary anterior teeth were included. The mean FOGTR obtained from BS and DBL were 3.19 ± 0.71 mm and 3.47 ± 1.29 mm, respectively (P = .004). The two measurements were identical 83.2% of the time, within 1-mm discrepancy 4.7% of the time, and > ± 1 mm discrepancy 12.1% of the time. When discrepancy was observed, BS underestimated DBL 14.2% of the time and overestimated 2.6% of the time. Though statistically significant, the correlation was weak (Pearson correlation coefficient r = .238, P = .0018). BS is an acceptably accurate and minimally invasive diagnostic tool for measuring FOGTR. However, while the mean difference between BS and DBL measurement is small (0.28 mm), the large range of difference can be alarming. Therefore, clinicians should always prepare alternative treatment options for IIP prior to extraction.

Part 1 of this series introduced the partial extraction therapies as a group of techniques for ridge preservation at immediate implant placement and beneath pontic sites. The concept proposes a paradigm shift away from extract and augment toward partly retaining the tooth root to preserve the ridge and prevent buccopalatal collapse. The revolutionary socket-shield technique was introduced in 2010; however, there has been no follow-up literature to guide the clinician in terms of procedural steps. While root submergence is well established, the socket-shield and pontic shield are still in their clinical infancy and require longterm clinical data before they can be proposed as routine in everyday implant dentistry. Yet without sound knowledge on how to carry out the partial extraction therapies, a global dental community cannot participate in their application or contribute to the growing knowledge base. In this, the second part of the series, the procedures for root submergence, socket-shield, and pontic shield are addressed, step by step, supplemented with applicable guidelines as the first such publication guiding the clinician to apply these root- and ridge-preservation techniques. Technical aspects and complication management are also addressed.

The impact of the laser tip on implant temperature when irradiating implants with lasers to treat peri-implantitis has received little attention. The present study was designed to assess the influence of two laser tips (sapphire chisel [MC3] and radial firing perio [RFP]) on temperature change of an implant irradiated with an Er,Cr:YSGG laser in vitro under various operational conditions. The results suggest that Er,Cr:YSGG irradiation using either tip with supplemental cooling can be a thermally safe approach to implant decontamination. However, use of the RFP tip consistently resulted in a greater temperature rise. The MC3 tip thus may be preferable to the RFP tip for open-flap implant debridement.

This multicenter prospective case series study aimed to evaluate the outcome of periodontal regenerative therapy using a deproteinized bovine bone mineral (DBBM) in combination with a collagen barrier (CB) in the treatment of intrabony defects. A total of 36 nonsmoking patients with chronic periodontitis were recruited in five centers in Japan. All patients had at least one intrabony defect of ≥ 3 mm. The surgical procedures included access for debridement using a papilla preservation technique. Defects were filled with DBBM and covered with CB. Clinical evidence after 6 months supported the effectiveness of the combination therapy in the treatment of intrabony defects.

The objective of this study was to quantitatively determine ridge contour changes after different alveolar ridge preservation techniques. An initial total of 40 patients provided a final total of 35 single-gap extraction sites. After tooth removal, the socket was subjected to one of four treatment modalities: placement of a deproteinized bovine bone mineral (DBBM; Endobon) covered with a soft tissue punch from the palate (Tx1); placement of DBBM without soft tissue punch (Tx2); placement of an adsorbable collagen membrane (Osseoguard) covering the DBBM (Tx3); and no additional treatment (control). Silicone impressions were obtained before and 6 months after tooth extraction for quantitative-volumetric evaluation on stone cast models. Bone quality and need for further bone augmentation were also noted. Tx1 and Tx3 resulted in significantly less bucco-oral tissue loss when compared to Tx2 and the control group. Premolar teeth and teeth extracted for traumatic reasons revealed significantly less tissue loss. Using barrier membranes or soft tissue punches in addition to placement of DBBM seems to be advantageous to limit bucco-oral tissue atrophy. The clinical benefit, however, is still questionable.

The purpose of the present study was to compare two different surgical procedures, connective tissue graft and guided bone regeneration, when applied in conjunction with implant placement. Probing pocket depth and the recession depth were recorded at the implant site after crown placement (T1) and at the 1-year follow-up (T2), while the keratinized tissue height and the buccal mucosa thickness were recorded at three different time points: at the time of implant surgery (T0), after crown placement, and at the 1-year followup. No statistically significant differences in peri-implant mucosa thickness, recession, or other periodontal parameters were recorded at adjacent teeth.

Well-coordinated interdisciplinary dental treatments provide the best esthetic, functional, and long-term results for patients. However, the length of such treatment, which may involve orthodontics, ridge augmentation, and dental implants, often deters patients from pursuing them. The two case reports presented here aim to present the advantage of simultaneous orthodontic molar uprighting and ridge augmentation procedures for future implant site development. Selective decortication of the alveolar bone, performed simultaneously with bone grafting, can accelerate the tooth uprighting process and synergistically reduce treatment duration. Two cases with bilaterally missing mandibular first molars were treated with this approach. In both patients, surgically accelerated uprighting of molars occurred 1.6 times faster than the contralateral site, where no surgery was performed. Additionally, ridge augmentation was successfully achieved with 2.5 to 5 mm of horizontal bone gain during the molar uprighting process.

Osseous resective surgery has been widely advocated in the treatment of periodontitis. The treatment traditionally has been done with rotary and manual instruments, but piezoelectric devices recently have also been used. A total of 20 adult patients diagnosed with moderate to severe chronic periodontitis were selected. A split-mouth study design was conducted such that one sextant was operated using piezoelectric bone surgery (test) and one with traditional instruments (control) in two separate sessions. Patients were asked to evaluate their perception of cold sensitivity, spontaneous pain, bleeding, swelling, and chewing discomfort. Piezoelectric bone surgery seems to be tolerated slightly better than conventional rotary instruments.

A 35-year-old woman was referred to the Department of Oral Medicine and Orofacial Surgery after several recurrences of an ossifying fibroma (OF) that affected the free and attached gingiva of the maxillary right central incisor. Surgery was performed with a complete excision of the lesion together with the surrounding healthy tissue up to the bone. To guide the healing of the anterior esthetic framework and the excised tissues, a porcine collagen matrix as an alternative to connective tissue graft was used. After an 18-month follow-up, the lesion had not recurred and keratinized gingiva had formed around the area.

The aim of this study was to establish the radiopacity of cements used in implantretained fixed partial dentures with respect to implant material, enamel, and dentin. A sample of 10 specimens of 13 different cements, implants, enamel, and dentin were prepared. Radiographs of the specimens and aluminum step wedges were acquired. Mean gray values of specimens were measured using digital imaging software. Kolmogorov-Smirnov and Shapiro-Wilk normality tests and independent t test were used (P = .05). Implantlink Semi, Premier, and Dentotemp had the lowest radiopacity values; GC FujiTemp LT, Multilink Implant, Poly-F Plus, Cavex-Temporary, and Panavia SA showed the highest. Within the limitations of the study, cements containing zinc oxide and ytterbium-trifluoride can be recommended for cementation of implant-retained restorations.

The purpose of this study was to develop a new method for a peri-implantitis model in beagle dogs in which a stainless steel ligature (SSL) was used independently. A total of 36 Straumann dental implants were placed in six beagle dogs 1 month after all mandibular premolars were extracted. After 3 months, SSLs were placed in a submarginal position on the implants to induce peri-implantitis and were not replaced during the 12-week tissue breakdown period. Inducing peri-implantitis in the beagles with an SSL is a rapid, effective, and simple method.

Implant-supported fixed complete dentures, often referred to as hybrid prostheses, have been associated with high implant survival rates but also with a high incidence of mechanical prosthetic complications. The most frequent of these complications have been fracture and wear of the veneering material. The proposed design concept incorporates the occlusal surfaces of the posterior teeth as part of a digital milled metal framework by designing the posterior first molars in full contour as part of the framework. The framework can be designed, scanned, and milled from a titanium blank using a milling machine. Acrylic resin teeth can then be placed on the framework by conventional protocol. The metal occlusal surfaces of the titanium-countered molars will be at centric occlusion. It is hypothesized that metal occlusal surfaces in the posterior region may reduce occlusal wear in these types of prostheses. When the proposed design protocol is followed, the connection between the metal frame and the cantilever part of the prosthesis is reinforced, which may lead to fewer fractures of the metal framework.

Immediate loading has proven to be a predictable modality for restorations with titanium dental implants. An increasing number of articles indicate that zirconia implants might osseointegrate to a similar extent in this context. This 5-year case report describes an outpatient maxillary restoration with eight immediately loaded zirconia implants. Implantation followed extensive bone augmentation. At the 5-year follow-up, all implants were still well osseointegrated clinically and radiologically. No major bone loss or periimplantitis had occurred in spite of temporary insufficient patient compliance. More research and studies are needed to confirm these results.