International Journal of Periodontics & Restorative Dentistry, 02/2015

The design of an implant-abutment interface may have an impact on the peri-implant soft tissue esthetics. In an ongoing randomized controlled trial (RCT) with 141 participants, the authors evaluated the peri-implant tissue responses around three different implant-abutment interface designs used to replace single teeth in the esthetic zone. The aim of this report is to describe the treatment protocol utilized in this ongoing RCT by (1) demonstrating in detail a clinical case treated under this protocol and (2) reporting peri-implant soft tissue responses in a cohort of 12 representative cases from the RCT at 1-year follow-up. Male and female adults requiring single implants in the anterior maxilla were enrolled in the RCT according to the study protocol. Five months following any required extraction and/or socket bone grafting/ridge augmentation, one of the following three implant-abutment interfaces was placed and immediately provisionalized: (1) conical interface (CI; OsseoSpeed, Dentsply Implants), n = 4; (2) flat-to-flat interface (FI; NobelSpeedy Replace, Nobel Biocare), n = 4; or (3) platform-switch interface (PS; NanoTite Certain Prevail, Biomet 3i), n = 4. Twelve weeks later, definitive crowns were delivered. Throughout the treatment, peri-implant buccal gingival zenith height and mesial/distal papilla height were measured on stereotactic device photographs, and pink esthetic scores (PES) were determined. The demographics of the participants in each of the three implant-abutment interface groups were very similar. All 12 study sites had ideal ridge form with a minimum width of 5.5 mm following implant site development performed according to the described treatment protocol. Using this treatment protocol for single-tooth replacement in the anterior maxilla, the clinicians were able to obtain esthetic peri-implant soft tissue outcomes with all three types of implant-abutment interface designs at 1-year follow-up as shown by the Canfield data and PES. The proposed treatment protocol for single-tooth replacement in the esthetic zone provides a reliable method to obtain and assess the esthetic outcome as a function of implant-abutment interface design and is now in its fifth year of follow-up.

This case report shows the combined use of piezosurgical and orthodontic procedures to successfully relocate two severely malpositioned implants in the anterior maxilla by moving them separately, with the objective of attaining functional prosthetic restoration and acceptable esthetics.

The objective of this study was to assess implant therapy after a staged guided bone regeneration procedure in the anterior maxilla by lateralization of the nasopalatine nerve and vessel bundle. Neurosensory function following augmentative procedures and implant placement, assessed using a standardized questionnaire and clinical examination, were the primary outcome variables measured. This retrospective study included patients with a bone defect in the anterior maxilla in need of horizontal and/or vertical ridge augmentation prior to dental implant placement. The surgical sites were allowed to heal for at least 6 months before placement of dental implants. All patients received fixed implant-supported restorations and entered into a tightly scheduled maintenance program. In addition to the maintenance program, patients were recalled for a clinical examination and to fill out a questionnaire to assess any changes in the neurosensory function of the nasopalatine nerve at least 6 months after function. Twenty patients were included in the study from February 2001 to December 2010. They received a total of 51 implants after augmentation of the alveolar crest and lateralization of the nasopalatine nerve. The follow-up examination for questionnaire and neurosensory assessment was scheduled after a mean period of 4.18 years of function. None of the patients examined reported any pain, they did not have less or an altered sensation, and they did not experience a "foreign body" feeling in the area of surgery. Overall, 6 patients out of 20 (30%) showed palatal sensibility alterations of the soft tissues in the region of the maxillary canines and incisors resulting in a risk for a neurosensory change of 0.45 mucosal teeth regions per patient after ridge augmentation with lateralization of the nasopalatine nerve. Regeneration of bone defects in the anterior maxilla by horizontal and/or vertical ridge augmentation and lateralization of the nasopalatine nerve prior to dental implant placement is a predictable surgical technique. Whether or not there were clinically measurable impairments of neurosensory function, the patients did not report them or were not bothered by them.

The purpose of this study was to evaluate the efficacy of Mucograft (MG; a porcine-derived purified collagen membrane) to increase the thickness and height of the buccal soft tissue when placed at the time of implant placement in patients with thin or deficient keratinized tissue (KT). The primary endpoint of the study was the change in thickness and height of the buccal KT. Secondary endpoints included stability of the midbuccal soft tissue level; clinician rating of color, texture, and contour of treatment site; probing pocket depths (PPDs); assessment of satisfaction outcome; and patient assessment of pain/discomfort. Thirty-two patients were enrolled and 31 patients completed the study. There were no statistically significant (SS) differences between the MG and control groups for height measures. There was no SS difference for KT thickness (P = .117) between the groups at the final measurement (3 months postsurgery). However, there was an SS difference (P = .009) in favor of the MG group when comparing the difference in presurgical KT thickness to that 3 months postsurgery. Thus, MG was successful (compared to the control) in increasing the buccal KT. There were no SS differences between the groups for any of the other endpoints, including color, texture, contour, and pain assessment at any visit or successful outcome between the treatment group and the control. More cases and longer follow-up of implants placed with MG are needed to verify the results of this randomized prospective study.

In the maxillary arch from premolar to premolar, 26 single dental implants were inserted in fresh extraction sockets and immediately provisionalized. The bone-to-implant gap was grafted with a bovine bone mineral. After 3 months, definitive ceramic crowns were placed. At baseline and after 1 year, the soft tissue horizontal width, mesiodistal papillary level, midfacial gingival level, and pink esthetic score were evaluated. No statistical differences were found between baseline and 1 year for all parameters. Immediate singletooth implants, with immediate restoration, are capable of maintaining the soft tissue contour and esthetics compared to the pretreatment status.

An alternative prosthetic treatment approach for single implants in the maxillary esthetic zone with an improper implant axis, limited interocclusal distance, inadequate abutment retention, and screw holes located at the labial surface is presented in this clinical report. The gingiva and soft tissues were contoured with provisional composite restorations to mimic the emergence profile of lateral incisors. Prefabricated zirconia abutments were customized with laminate veneer preparations by appropriate ceramic build-up with reference from the reshaped gingiva to avoid labiolingual overcontour. The laminate veneers were fabricated by computer-aided design/ computer-assisted manufacture to cover the screw hole of the angulated abutment at the labial surface. Preliminary results revealed improvement in esthetics; however, long-term clinical follow-up should be performed.

This study compared the margin profile and surface roughness created by the tips of four different finishing instruments: fine diamond, dura white stone, tungsten carbide, and ultrasonic diamond-coated tips (UDTs). The aim was to determine which of these instruments produced the smoothest finish and created the most evenly contoured margin characteristics. It was hypothesized that UDTs would produce a rougher dentin surface than a fine diamond bur, that a tungsten carbide bur would provide a smoother finish than a fine diamond, and that the dura white stone would produce an intermediate finish. Forty extracted premolars were divided into two groups. For the first group, a 1.5 x 3.0-mm dentin slot was prepared in 30 teeth using a control 50-μm diamond bur, followed by one of the four finishing instruments. The surface roughness (Ra) was then measured using a surface profilometer and a one-way analysis of variance followed by a post hoc Bonferroni test to assess whether any statistical difference existed among the Ra values. For the second group, shoulder margins were prepared in 10 teeth. They were then refined with one of the four finishing instruments and examined with scanning electron microscopy (SEM). The fine diamond bur created a significantly smoother surface than the control diamond (P < .001), UDTs (P < .007), and tungsten carbide bur (P < .010). The fine diamond was not found to be significantly smoother than the dura white stone. SEM images of the fine diamond showed divoting on the margin floor. The dura stone showed a well-defined, undamaged margin. The tungsten carbide bur created frequent chipping in enamel margins. The UDT specimens showed an inconsistent finish and discrete patches of open dentinal tubules. The fine diamond created the lowest Ra values; however, the dura stone offered efficient finishing and less damage to the margin profile.

This study aimed to determine the effect of adhesive direct composite restorations, endodontic treatments, and fatigue treatments on the cuspal deflection of maxillary premolars subjected to different cyclic occlusal forces. Thirty intact maxillary second premolars were selected. Ten teeth were left untreated (group IN), 10 teeth were subjected to endodontic and restorative treatment (group FL), and the remaining 10 teeth were subjected to endodontic, restorative, and fatigue treatments (group FT). All teeth were subjected to 5 occlusal compressive loading forces (98, 147, 196, 245, and 294 N) with a universal testing device. A total of 15 experimental groups were obtained with 3 tooth conditions (IN, FL, FT) and 5 different occlusal loading values. Deflection amounts (μm) were measured with laser sensors and recorded, and obtained data were statistically analyzed with one-way analysis of variance at a significance level of .05. Mean cuspal deflection values (μm) and SDs of experimental groups ranged as follows: IN-98 (24.4 ± 19.8), IN-147 (34.8 ± 28.9), IN-196 (43.8 ± 34.7), IN-245 (54.5 ± 46.4), IN-294 (60.3 ± 50.6), FL-98 (56 ± 49.1), FL-147 (62.6 ± 49.6), FL-196 (72.4 ± 52.1), FL-245 (81.3 ± 56), FL-294 (92.2 ± 60.9), FT-98 (77.2 ± 80.9), FT-147 (83.4 ± 81.3), FT-196 (92.6 ± 83.7), FT-245 (102.7 ± 85.4), and FT-294 (124.2 ± 89.5). Mean values of three main experimental groups were as follows: IN (43.5 μm), FL (72.9 μm) and FT (96.0 μm). Significant differences were found between the three main groups and relevant subgroups (P < .001). Highest cuspal deflection values (CDV) were obtained in FT groups. Lowest CDV were obtained in IN groups. FL groups showed higher deflection values than IN groups. CDV increased progressively as the teeth were restored and subjected to fatigue treatment.

The purpose of this case series was to report the clinical outcomes and histologic findings of vertical ridge augmentation using a combination of titanium mesh and recombinant human platelet-derived growth factor BB (rhPDGF-BB). Two patients were included, and anorganic bovine bone particles were used. The bone graft was mixed with rhPDGF-BB and loaded onto the bony defect up to the level of the adjacent alveolar crest. A preadapted titanium mesh was placed over the grafted region; no areas of the grafted region were exposed. Postoperative healing was without complications. During reentry surgery for removal of the titanium mesh, all implants could be placed according to the prosthetic design. This report demonstrates the remarkable efficacy of guided bone regeneration using a combination of titanium mesh and rhPDGF for vertical ridge augmentation, thus expanding the indications for implant therapy and allowing recovery of the three-dimensional esthetic architecture in a severely resorbed alveolar ridge.

The goal of this study was to investigate outcomes of implants placed in the partially edentulous posterior maxilla and mandible and restored with two- to four-unit fixed prostheses that were functionally loaded immediately after implant placement. Forty-nine patients were treated, and 63 fixed prostheses were inserted on 140 implants. After an average of 8.6 months of follow-up, 2 implants failed-a cumulative success rate of 98.6%. These preliminary results support other findings that suggest patients with maxillary and mandibular partial posterior edentulism can confidently be treated with immediately loaded dental implants.

The aim of this prospective randomized clinical study was to evaluate, by means of an image analysis system, the efficacy of two different surgical procedures for the treatment of Miller Class I and II maxillary gingival recession. Patients treated for maxillary gingival recession were recruited and randomly divided into two groups: patients who received a coronally advanced flap with connective tissue graft (CAF + CTG) or CAF alone. Outcome parameters included complete root coverage, recession reduction, and keratinized tissue amount. Twenty-five patients completed the 12-month follow-up period. Patients in the CAF + CTG group showed a better primary outcome- gingival recession at 12 months-than CAF patients (P = .0001). Gingival recession at 12 months had a median of 0.5 (interquartile range [IQR] 0.5 to 0.6) in the CAF + CTG group and a median of 1.0 (IQR 0.9 to 1.1) in the CAF group. CAF + CTG and CAF groups had similar complete root coverage at 6 and 12 months. Recession and keratinized tissue width significantly decreased over time (P < .0001), with no effect of treatment or of treatment over time. Buccal probing depth had similar values over time (P = .28) and in the two groups (P = .52). Buccal clinical attachment level had similar values in the two groups (P = .87); moreover, mesial and distal clinical attachment levels did not show any variation over time (P = .88 and P = .68, respectively). By means of a computerized image analysis system better outcomes in terms of recession reduction after 12 months of follow-up were measured for maxillary gingival recessions treated with CAF and CTG. Adjunctive application of a CTG under a CAF increased the probability of achieving complete root coverage in maxillary Miller Class I and II defects (61.5% versus 83.3%; P = .38). Both treatments were equally effective in providing a consistent reduction of the baseline recession.

The aim of this study was to evaluate the performance of a double-layer technique using an acellular dermal matrix (ADM) in conjunction with a coronally advanced flap (CAF) in treating Miller Class I and II gingival recession defects. A total of 50 patients with isolated Class I and II gingival recession defects were treated. At 52 weeks, the mean recession defect decreased from 3.8 ± 0.9 mm to 0.2 ± 0.5 mm. This represents 94.7% root coverage. Complete root coverage was achieved in 80.0% of the cases. Statistical improvements also were found with probing depths and clinical attachment levels. These results support the use of a double-layer technique using ADM in conjunction with a CAF in treating Class I and II recession defects.

The objective of this pilot study was to investigate the potential role of -1562 C>T single nucleotide polymorphism (SNP) in the promoter region of the matrix metalloproteinase-9 (MMP-9) gene as a risk modulator in the development of multiple gingival recessions (MGRs) in young adults in the Serbian population. The study sample comprised 161 systemically healthy people: 60 with MGRs and 101 controls with healthy periodontal tissues. Genotyping was done using polymerase chain reaction/restriction fragment length polymorphism approach on DNA obtained from buccal swabs. Clinical measurements included vertical recession depth (VRD), clinical attachment level (CAL), keratinized gingival width (KGW), visible plaque index (PI), and bleeding on probing (BOP). Heterozygotes (CT) were significantly more frequent in the MGRs group than in the control group (P = .005) and carriers of the T allele had an approximately threefold increase of MGRs risk. Patients with the CT genotype exhibited significantly higher values of VRD and CAL and significantly lower values of KGW than patients with the wildtype genotype. Associations among different genotypes and periodontal biotypes in the MGRs group remained insignificant because all participants exhibited thin biotype. The -1562 C>T SNP in the promoter region of MMP-9 appears to be a risk factor for MGR development and a potential predictor of more severe clinical phenotype.

The purpose of this study was to demonstrate clinical outcomes of sandblasted, large-grit, acid-etched (SLA)-surfaced tapered implants when early loaded in partially edentulous spaces in the maxilla. SLA-surfaced implants were placed in participants in the maxillary posterior edentulous area. At the time of definitive restoration, participants were allocated either to group 1 (3-month loading group) or group 2 (6-month loading group). A total of 36 participants (18 people [35 implants] in group 1 and 18 [33 implants] in group 2) were analyzed. Clinical outcomes, including survival rate and peri-implant parameters such as marginal bone loss were measured 1 year after loading. The survival rate was 97.0% in group 1 and 100% in group 2. Marginal bone loss was 0.22 ± 0.34 mm in group 1 and 0.17 ± 0.25 mm in group 2 at 1 year after loading (P = .488). There were no significant differences between groups in keratinized mucosal width (P = .206), Plaque Index (P = .677), or Gingival Index (P = .558). With adequate remaining bone height and primary implant stability achieved, the 3-month early loading of SLA-surface tapered implants may be a viable choice when restoring posterior maxillary edentulous areas.

This study assessed the activities of antioxidant enzymes superoxide dismutase (SOD), glutathione reductase (GR), and catalase (CAT) and free radical damage marker malondialdehyde (MDA) levels in saliva of 30 patients with chronic periodontitis (CP) compared to 30 healthy controls by spectrophotometry. MDA levels were significantly elevated in the CP group, whereas the SOD, CAT, and GR activities were significantly reduced compared to healthy controls. MDA levels demonstrated a significant direct correlation with all periodontal parameters, whereas all antioxidant enzymes studied (SOD, CAT, and GR) showed an inverse correlation. These findings support the idea that oxidative stress has a role in periodontal disease pathogenesis.

This case report describes the bilateral reconstruction of a severely atrophic posterior mandible in a 30-year-old woman using allograft block versus particulate grafting in the inlay technique. Three months later, four dental implants were placed and bone core biopsy specimens were taken for histologic evaluation. During implant placement, the grafted sites were stable with good clinical osseointegration. The histologic analysis showed the presence of compact bone revealing areas of demarcation between grafted bone, newly formed bone, and bone-regenerated areas. Allografts might serve as an alternative to autogenous and heterologous grafting in posterior mandible augmentation using the inlay technique.

During orthodontic treatment, mechanical forces may change the components of gingival crevicular fluid (GCF), which reflects the cellular response in the periodontium. The objective of this study was to investigate the expressions of receptor activator of nuclear factor-kappa beta ligand (RANKL) and interleukin- 17A (IL-17A) in GCF in subjects with or without orthodontic appliances, the correlation between them, their gender predominance, and their relationship with treatment time. GCF was collected from 72 young people to detect the expressions of RANKL and IL-17A. Cytokine analysis was done with the help of enzyme-linked immunosorbent assay. Results showed that the expressions of RANKL and IL-17A were higher in the treatment group than the nontreatment group (P < .05) and higher in males than in females (P < .05). Their increments were well correlated with each other (r = 0.788, P = < .01) but were not time dependent. The authors concluded that these proteins increased in the treatment group and more in the young male orthodontic patients than in the female patients. The proteins were well correlated with each other.