International Journal of Periodontics & Restorative Dentistry, 03/2018

This multicenter retrospective clinical study was aimed at comparing the effects of an increase in vertical dimension of occlusion (VDO) in patients with fixed rehabilitations. Expert clinicians retrospectively evaluated 100 patients treated with an increase of the VDO and fixed dental prostheses (FDPs) supported by teeth, implants, or both. The patients were divided into three study groups according to the type of support of restorations in posterior areas, as follows: partially edentulous patients with posterior teeth-supported rehabilitations and no implants in posterior segments (group A), partially edentulous patients with posterior mixed rehabilitations and at least one osseointegrated implant in posterior segments (group B), and completely edentulous patients with posterior implant-supported rehabilitations (group C). The new VDO was tested with mock-ups, temporary restorations, or removable appliances. The patients were followed up for at least 1 year after the delivery of final restorations. Clinical variables were collected retrospectively, such as presence of referred self-reported bruxism and temporomandibular joint or muscle symptoms before treatment, extension of the dental arches, increase in VDO, restorative materials, and functional complications. Descriptive statistics were analyzed; the three experimental groups were compared with one-way analysis of variance (ANOVA) followed by Tukey post hoc test for the quantitative variables and with logistic regression using the likelihood ratio test for the qualitative variables. Statistically significant differences were reported among the experimental groups for functional complications. Functional and prosthetic complications after the VDO increase were not frequent. Functional complications were mainly noticed in group C but usually were no longer evident after 2 weeks. No significant differences were found between groups in terms of prosthetic complications and self-reported bruxism.

Recent systematic reviews point to the scarcity of single implants followed up longer than 5 years, and the incidence of biologic/technical complications is underreported. This prospective follow-up study documents 8- to 10-year clinical outcomes of immediately restored single implants in extraction sockets (immediate implant treatment [IIT]) and healed bone (conventional implant treatment [CIT]). Patients received a single, chemically modified, moderately rough titanium implant and a provisional crown on the day of surgery in the anterior maxilla (second premolar to second premolar). Provisional crowns were replaced by permanent crowns after 10 weeks. Implant survival, complications, crestal bone changes, plaque score, probing depth, and bleeding on probing were regularly recorded up to 10 years of followup. Of 16 patients who underwent IIT, 11 could be evaluated after 8 years. Of the 23 patients who received an implant in healed bone, 18 were finally evaluated. One implant failed in the IIT group at 12 weeks; all implants survived in the CIT group; 38% of the patients experienced at least one complication; 10% had one or more biologic complications, whereas 31% experienced one or more technical complications. There were no significant changes in crestal bone level from 1 to ≥ 8 years of follow-up for either group or between IIT and CIT at any time point (P ≥ .129). Only 6.9% (2 of 29) implants demonstrated progressive bone loss > 2 mm combined with pockets ≥ 6 mm. Immediately restored single implants in extraction sockets and healed ridges demonstrate good long-term outcomes in terms of implant survival, crestal bone loss, and peri-implant health. However, biologic and especially technical complications are common.

This report describes the long-term outcomes of nonsurgical periodontal therapy and supportive periodontal treatment (SPT) of a 21-year-old patient affected by generalized aggressive periodontitis at multiple teeth with a compromised prognosis. After 25 years of SPT, no teeth had been extracted and no periodontal pockets associated with bleeding on probing were present. Radiographic analysis showed an improvement in infrabony defects, demonstrating longterm improvement is possible with nonsurgical periodontal treatment provided that smoking is not present and the patient is included in a strict SPT.

Allogeneic bone blocks are commonly used for bone augmentation in implant dentistry. Allogeneic bone blocks have the advantage of containing growth factors and the original human scaffold. A major disadvantage is the risk of substantial graft volume decrease due to resorption. The purpose of this study was to evaluate whether corticocancellous allogeneic bone blocks can predictably maintain graft volume to allow implant placement and esthetic restoration. A total of 141 allogeneic bone blocks were placed in 117 patients, allowing for 183 implants. The implant success rate was 96.7% after 6 to 96 months of follow-up.

The use of the cone-in-cone connection to support definitive restorations was previously evaluated in cases involving full-acrylic resin or hybrid acrylic-resin composite prostheses. The aim of this study was to evaluate the performance of definitive fixed partial prostheses made with monolithic zirconia and supported by cone-in-cone abutments and integrated implants. Implants were placed into healed sites and fresh extraction sockets. The prostheses were placed in the posterior regions of partially edentulous patients after healing periods of 3 months. A total of 76 patients received fixed monolithic zirconia restorations splinted with cone-in-cone connections to two implants that were followed up yearly for 5 years. At each follow-up visit, peri-implant bone levels and pocket depths were recorded. Esthetic, functional, and biologic United States Public Health Services parameters modified by the World Dental Federation study design were assessed at the last follow-up appointments. The opposing dentition was categorized by type of restoration and supporting structure at the time of placement of the definitive zirconia partial restoration and at the 5-year follow-up. The treatment achieved an 88.2% success rate and a 97.4% survival rate at the 5-year follow-up. None of the prostheses became loose or detached. One fixed prosthesis (0.76%) fractured 41 months after placement. No significant difference involving peri-implant bone and probing levels between the experimental times was found. The results of this research indicated that abutment-prosthesis cone-in-cone connections were successful within the 5-year study period.

Use of collagen membrane (CM) with deproteinized bovine bone mineral (DBBM) and enamel matrix derivative (EMD) in periodontal regenerative therapy was evaluated. A total of 40 intrabony defects in periodontitis patients were treated. Clinical parameters and filled bone volume (FBV) and rate (FBR) were assessed. Probing pocket depth (PPD) was reduced significantly at 12 months with CM treatment, while clinical attachment level (CAL), FBV, and FBR showed similar improvements. In stratified analyses, CM-treated thick-biotype patients showed significant improvement in PPD and CAL. Regenerative therapy with the use of EMD and DBBM showed similar improvements in periodontal tissue regeneration with or without CM. The combination with CM appeared to influence the healing of soft tissue and was effective in decreasing pocket depth.

The presence of interdental papilla between the maxillary central incisors has a considerable influence on harmonizing esthetics and biologic functions. Preliminary investigations indicate an association between tooth shapes and periodontal characteristics. This study aimed to evaluate the prevalence of morphologic variation in maxillary central incisors and its influence on gingival characteristics. It was determined that varied crown forms have a definite influence on gingival characteristics, which could act as a valuable guideline in periodontal, restorative, and anterior implant placement procedures.

The objective of this study was to evaluate the effectiveness of precise threedimensional hydroxyapatite printed micro- and macrochannel devices for alveolar ridge augmentation in a canine model. All grafts induced minimal inflammatory and fibrotic reactions. Examination of undecalcified sections revealed that both types of grafts demonstrated bone ingrowth. The majority of the bone growth into the block graft was into the channels, though a portion grew directly into the construct in the form of small bony spicules. In conclusion, bone ingrowth was readily demonstrated in the middle of the implanted printed devices.

The CIELab and CIEDE2000 coverage error (ΔE*_COV and ΔE'_COV, respectively) of basic shades of different gingival shade guides and gingiva-colored restorative dental materials (n = 5) was calculated as compared to a previously compiled database on healthy human gingiva. Data were analyzed using analysis of variance with Tukey-Kramer multiple-comparison test (P < .05). A 50:50% acceptability threshold of 4.6 for ΔE* and 4.1 for ΔE' was used to interpret the results. ΔE*_COV / ΔE'_COV ranged from 4.4/3.5 to 8.6/6.9. The majority of gingival shade guides and gingiva-colored restorative materials exhibited statistically significant coverage errors above the 50:50% acceptability threshold and uneven shade distribution.

The purpose of this case report was to introduce a novel technique for de-epithelializing autogenous gingival graft that can be combined with coronally advanced flap for root coverage and soft tissue augmentation. This technique allows for easier, predictable harvesting of connective tissue of excellent quality and quantity without inclusion of undesirable submucosa or adipose tissues. Reduced surgical chair time and double protection of the donor site using the combination of cyanoacrylate and periodontal dressing allowed for uneventful postoperative healing.

Tooth loss generally leads to a corresponding loss of supporting bone structures, jeopardizing correct implant placement. Bone augmentation procedures facilitate reconstruction of the alveolar contours but lengthen treatment time by about 4 to 9 months. The aim of this case series report is to describe the short-term results of the combination of three-dimensional bone augmentation using the shell technique in conjunction with simultaneous implantation. A total of 10 patients who underwent autologous bone augmentation using the shell technique with simultaneous implantation were retrospectively examined. The shell technique is an augmentation procedure using thin cortical bone plates adapted to the buccal and oral walls of the defect to rebuild the contours of the alveolar ridge. The remaining spaces are filled with bone chips. Healing time before second stage surgery was 4 months. The vertical bone defect at the beginning (VD), the height of the vertical bone graft, resorption at the time of second-stage surgery (BR1) and 1 year after prosthetic rehabilitation (BR2), the total resorption between augmentation and 1 year (BRtot), and the vertical bone loss of the implant (VBL) were measured. VD was 3.1 mm. Values for BR1 and BR2 were 0.4 and 0.45 mm, respectively, resulting in a total bone loss of 0.85 mm of bone loss (BRtot). VBL was 0.45 mm 1 year after prosthetic rehabilitation. The simultaneous approach of vertical bone augmentation in the shell technique and implantation shows excellent results in bone reconstruction and stability up to 1 year after prosthetic reconstruction and can shorten treatment time by 4 to 9 months.

When the edentulous posterior maxilla shows severe atrophy (Cawood and Howell Class V to VI), the traditional approach requires at least two surgical procedures. The first is a sinus lift (alone or with guided bone regeneration), and the second is to position implants. This article illustrates a technique that allows threedimensional reconstruction of the sinus, placing an allogenous fresh bone block and simultaneous implant positioning using a computer-guided implant surgery.

The aim of this study was to analyze the degree of mineralization around nine clinically stable titanium dental implants retrieved after 2 months to 17 years for mechanical complications from five patients. The micromorphology and microchemistry of the interface bone at the coronal and apical sides of the threads were analyzed by environmental scanning electron microscope and energydispersive X-ray spectroscopy (EDX) on histologic samples. Mineralization was investigated by atomic calcium-to-nitrogen (Ca/N), phosphorous-to-nitrogen (P/N), and calcium-to-phosphorous (Ca/P) ratio evaluation (statistical analysis by two-way analysis of variance with Student-Newman-Keuls; P < .05). EDX showed higher Ca/N, P/N, and Ca/P values for the bone at the coronal side compared to the apical side of the threads in the long-term (≥ 14 years) samples. The two most significant findings were that (1) the interface bone located at the coronal side of the implant threads was generally more mineralized than the interface bone located at the apical side, and (2) the mineralization of the peri-implant bone at the interface increased over time. A higher degree of mineralization was found at 2 months in an immediately loaded implant when compared to the 2-month submerged unloaded control, likely related to the different remodeling events (coronal vs apical side of the implant threads) due to the direction of the loading forces.

Peri-implant disease has developed over the last few years as a complication that is often difficult to resolve. The disease process is mainly attributed to bacterial infection. Proposed combined therapies use broad-spectrum antibiotics to halt its progression. A major associated risk is the undetected development of superinfections that are difficult to eradicate. A group of healthy individuals with advanced peri-implantitis (PI) were referred for evaluation due to severe, rapidly progressive bone loss. Previous nonsurgical and empiric antibiotic therapy had been rendered. Culture and polymerase chain reaction-based identification were performed for PI lesions, healthy implants, and saliva. Clinical and radiographic examinations revealed peri-implant bleeding on probing, deep pockets, and severe radiographic bone loss with absence of lamina dura. A number of superinfecting agents were identified, such as Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Candida albicans, and Epstein-Barr virus (EBV). EBV is significantly more prevalent at peri-implantitis sites than at healthy implants and in saliva. Specific systemic antimicrobial therapy and nonsurgical or surgical debridement may eradicate some opportunistic pathogens, but follow-up tests should be performed to identify potential emerging pathogenic microbiota, such as C albicans and enteric rods, at peri-implant sites. Antifungal and antiviral therapy may be needed. Due to the extent and severity of tissue loss, some implants were removed. Peri-implant superinfections are a major risk associated with broad-spectrum antibiotics in immunocompetent individuals. Lack of follow-up and antibiotic susceptibility testing and indiscriminate empiric treatment regimens may lead to ongoing microbial challenge that exacerbates and maintains the disease progression. Personalized periodontal supportive therapy could prevent risks by sustaining a healthy microbial ecologic balance, reducing specific pathogen proportions, maintaining optimal plaque control, and detecting early signs of inflammation.

The extension of sinus floor augmentation beyond the edentulous area, apical to the adjacent teeth, has many therapeutic advantages, but the reliability and safety of the procedure has not been assessed in depth. The present study compares the gain of bone anterior and posterior to the edentulous area and evaluates potential advantages and limitations in the clinical setting. The maximum vertical bone height in the edentulous and extended maxillary sinus augmentation (EMSA) areas and the thickness of the sinus membrane of 65 patients were measured. Those measurements were analyzed using the t test and Pearson correlations. The average vertical bone gain was 11.98 ± 3.53 mm in the edentulous sinus area and 8.60 ± 3.89 mm in the EMSA area (P < .05). Minor perforations of the sinus membrane occurred in 4 patients. There were no postsurgical graft contaminations or periradicular changes during follow-up. EMSA is a reliable and safe procedure with a very low complication rate. This approach is effective and safe for patients who have lost part of their posterior dentition. It enables future implant placement while avoiding the need for sinus reentry and proximal teeth extraction.

The aim of this pilot in vitro study was to evaluate material wear and temperature variations after using conventional rotating bur and piezosurgical insert for osseous resective surgery in bovine bone blocks under physiologic irrigation. Wear evaluation was carried out by measuring cutting time, and wear mechanisms were analyzed by scanning electron microscopy. Time analysis showed greater material wear and higher heat production with the piezoelectric insert. However, temperatures remained below values of clinical concern even after a cutting time of 20 minutes. Conversely, bone surface appeared irregular in shape with bone debris and signs of thermal damage on the bur-drilled surface, probably due to the more traumatic action of the diamond-coated bur.

The marginal integrity of all-ceramic crowns for anterior and posterior teeth were evaluated. A total of 60 ceramic crowns (In-Ceram Alumina, IPS e.max Press, and Lava) were fabricated for the epoxy resin maxillary first central incisor and first molar and divided into three groups (n = 20). The crowns were measured at the facial, lingual, mesial, and distal finish lines (52 points) before and after cementation using scanning electron microscopy. The results were analyzed using one-way analysis of variance, paired samples t test, and independent t test. The mean values of marginal gaps were within acceptable clinical limits before and after cementation. The values of the anterior crowns at the buccal finish line were higher than those at the proximal finish line areas (P < .05). However, these were insignificant at four measurement areas for posterior crowns (P > .05). Marginal gaps of crowns at the anterior teeth were higher than at the posterior teeth for all groups.

The objective of this study was to evaluate the influence of a modified surgical and prosthodontic ridge preservation protocol with direct insertion of a temporary but fixed reconstruction at the time of extraction. After atraumatic extraction and filling of the socket with an in situ-hardening graft material to fortify the outline position of the marginal rim of the former socket, the change in buccal volume was documented with an analog impression and digital scanning and processing workflow of the data. Changes in the soft tissue profile were calculated as the difference between the digitized surface on the day of extraction and at the 6-month follow-up. The results indicate that in the group with stabilization of the graft material with a fixed temporary appliance, the amount of buccal volume loss was reduced to −1.06 mm (95% confidence interval = −1.8 to −0.29) in comparison to the group without temporary reconstruction for sites in the mandible (−2.09 mm), and for the group in the maxilla without temporary reconstruction (−2.17 mm). The difference was statistically significant (P = .0059). Using a singlestage approach while simultaneously reconstructing the esthetic appearance of the patient with a fixed temporary appliance, the described modification of current ridge preservation techniques is able to reduce buccal volume loss after extraction. This might aid the final esthetic rehabilitation of a visible site after extraction by means of a conventional or implant-based fixed reconstruction.