International Journal of Periodontics & Restorative Dentistry, 04/2014

Various types of dental preparations for laminate veneers have been proposed, depending on factors such as the properties of the ceramic material, remaining dental structure color, need for altering the dental contour, laboratory fabrication technique, and occlusal relationships. Clinical observations of successes and failures associated with the development of techniques and materials have allowed some safe parameters to be delineated for effectively performing dental preparations for ceramic veneers or even placing veneers without any preparation. This article describes the use of an additive diagnostic wax-up that is transferred to the mouth by means of an intraoral mock-up (aesthetic pre-evaluative temporary) with associated mathematic parameters to guide dental preparations. This technique, called Do the Math and presented here in the form of a clinical case report, aims to avoid excessive or incorrect tooth preparation by indicating the exact amount and location of the tooth reduction necessary to attain the desired color and shape.

The prevalence of peri-implantitis is of concern to all clinicians participating in implant dentistry. Peri-implant inflammation results in the loss of supporting bone for the implant that may or may not be accompanied by bleeding on probing and suppuration. Early diagnosis and intervention are mandated, but there is a paucity of evidence leading to the most effective therapy. There is agreement that one of the challenges in surgically treating peri-implant defects is the process of cleaning and decontaminating the implant surface, which may be contaminated by bacterial aggregates. This preclinical canine study investigates the erbium:yttrium-aluminum-garnet laser to decontaminate the complex rough surface of the implant by stripping the contaminated oxide layer for induction of hard and soft tissue adaptation to a compromised or failing implant. The results provide evidence of new bone-to-implant contact established at a level representative of the size of the defects. The soft tissues contain little or no evidence of inflammation, which can be interpreted as an arrest of the disease progression process. The results can be translated to a treatment goal of stabilizing the prognosis of an implant that has been compromised.

The purpose of this report is to present a case series of gingiva-colored abutments utilized to meet patients' esthetic needs. The color of the abutment was determined by evaluating the color of the patients' marginal gingiva using a digital shade guide. Thereafter, anodic oxidation was performed on computer-aided design/computer-assisted manufacture abutments. The baseline digital color information was compared with the color of the gingiva after 1.5 years in three patients. The gingival colors as well as the marginal bone and soft tissue levels after 1.5 years were comparable to the baseline values. Thus, the gingiva-colored abutments obtained by anodic oxidation provided improved esthetics, especially for patients with thin gingival biotypes.

This clinical study assessed at 5 years both implant survival and peri-implant tissue architecture of immediately provisionalized implants placed 4 to 6 months following augmentation with demineralized bovine bone allograft and collagen membrane. Of 23 implants in 19 patients, one implant failed prior to loading (95.6% survival). Implant tissue relationships were stable following implant placement; marginal bone level changes from implant placement to 5 years (mean ± SD: -0.18 ± 0.79 mm, range: -1.6 to 1.4 mm, P = .51), the mesial and distal papilla length changes (mesial mean ± SD: 1.14 ± 0.92 mm, P < .001; distal mean ± SD: 0.74 ± 1.46 mm, P = .04), and the unchanged mucosal zenith location (mean ± SD: 0.24 ± 0.93 mm, P = .15) were recorded. There were no major surgical complications during the 5-year period. When augmentation is required, subsequent dental implant placement in the anterior maxilla may be achieved using immediate placement and provisionalization protocol to attain osseointegration success and stable peri-implant tissue responses.

This case report presents a 3-year follow-up of the clinical outcomes of a combined surgical therapy for advanced peri-implantitis with concomitant soft tissue volume augmentation using a collagen matrix. One patient suffering from advanced peri-implantitis and a thin mucosal biotype underwent access flap surgery, implantoplasty at buccally and supracrestally exposed implant parts, and augmentation of the intrabony components using a natural bone mineral and a native collagen membrane after surface decontamination. A collagen matrix was applied to the wound area to increase soft tissue volume and support transmucosal healing. The following clinical parameters were recorded over a period of 3 years: bleeding on probing (BOP), probing depth (PD), mucosal recession (MR), clinical attachment level (CAL), and width of keratinized mucosa (KM). At 36 months, the combined surgical procedure was associated with a clinically important reduction in mean BOP (100%), PD (4.3 ± 0.5 mm), and CAL (4.4 ± 0.4 mm). Site-level analysis of the buccal aspects pointed to an increase in MR (-1.0 ± 0.4 mm) and a decrease in KM (-1.3 ± 0.5 mm) values at 12 months. However, a regain in mucosal height and KM was noted at 24 months, even reaching respective baseline values after 36 months of healing. The presented combined surgical procedure was effective in controlling an advanced peri-implantitis lesion without compromising the overall esthetic outcome in the long term.

Twenty-four periodontal intraosseous defects were accessed with a buccal single-flap approach (SFA) and treated with enamel matrix derivative (EMD) or EMD + deproteinized bovine bone mineral (DBBM) according to the surgeon's discretion. EMD with or without DBBM was clinically effective in the treatment of periodontal intraosseous defects accessed with a buccal SFA. The adjunctive use of DBBM in predominantly onewall defects seemed to compensate for, at least in part, the unfavorable osseous characteristics in terms of the outcomes of the procedure.

The aim of this pilot study was to obtain preliminary data regarding the effectiveness of three different alveolar ridge preservation modalities as compared with a control. Subjects in need of single-rooted tooth extraction were recruited and randomly allocated to one of four treatment groups: group 1 (control)-collagen plug; group 2-socket grafting and polytetrafluoroethylene (PTFE) barrier; group 3-socket grafting, buccal overbuilding, and PTFE barrier; group 4-socket grafting, collagen barrier, and PTFE barrier. The grafting material used in all groups was an allograft. At 16 weeks, surgical reentry was performed, and a bone core biopsy was harvested for histomorphometric analysis. A cone beam computed tomography scan was obtained at baseline and before surgical reentry. Clinical (keratinized mucosa [KM] and buccolingual ridge width [RW] changes) and volumetric outcomes were statistically analyzed. A total of 20 patients were recruited (5 patients per group). KM and buccolingual RW changes were minimal during the 16-week healing period for all groups, with no statistically significant differences. Volumetric analyses revealed comparable alveolar ridge resorption values for groups 1, 2, and 4 (3%, 7%, and 5%, respectively), while group 3 exhibited more reduction (16%). Histomorphometric analysis revealed the presence of adequate average values of mineralized tissue (group 1, 46.4%; group 2, 28.88%; group 3, 48.81%; group 4, 41.13%). Based on the clinical and volumetric outcomes, none of the ridge preservation modalities was superior to the control. The combination allograft (freeze-dried bone allograft and demineralized freeze-dried bone allograft) employed in this study appears to be a safe and adequate biomaterial for intraoral grafting.

A variety of surgical procedures have been developed to accelerate orthodontic treatment of adult patients seeking to enhance their smiles or masticatory function. While most of these techniques are invasive, the minimally invasive piezocision technique reduces trauma by combining microincisions and localized piezoelectric bone surgery. A method for combining piezocision with the use of computed tomography is presented here. By creating a three-dimensional model of the arch, the depth and location of the corticotomies can be precisely planned, and a surgical guide can be fabricated and used to prevent any damage to the dental roots.

After tooth extraction, 14 alveolar sockets were grafted with porous bovine bone mineral particles and covered with non-cross-linked collagen membrane (test group), and 14 alveolar sockets were left uncovered. At 5 and 12 weeks, microvascular density (MVD), collagen content, and amount of lymphocytes (Lym) T and B were analyzed in soft tissue. At 5 weeks, MVD was significantly lower and Lym T was significantly higher in tests than in controls (P < .05). At 12 weeks no differences were found. Placement of resorbable membrane seems to induce an initial and transient modification of the normal wound healing process of the soft tissue.

Histologic and clinical studies confirm that laser-microtextured implant collars favor the attachment of connective fibers and reduce probing depth and periimplant bone loss when compared with machined collars. This prospective study aimed at assessing the alveolar dimensional changes after immediate placement of a transmucosal implant with a Laser-Lok microtextured collar associated with bone regenerative procedures. Thirteen implants were placed immediately into single-rooted extraction sockets. Peri-implant defects were treated with bovinederived xenografts and resorbable collagen membranes. At 6-month surgical reentry, the Laser-Lok microtextured collar provided more favorable conditions for the attachment of hard and soft tissues and reduced the alveolar bone loss.

No human studies exist on the use of recombinant human bone morphogenetic protein 2 (rhBMP-2) on an absorbable collagen sponge (ACS) as a sole graft material for lateral ridge augmentation in large ridge defect sites. This series evaluates the treatment outcome of maxillary anterior lateral ridge augmentation with rhBMP-2/ACS. Twenty patients were treated with rhBMP-2/ACS and fixation screws for space maintenance. Cone beam volumetric tomography measurements were used to determine gain in ridge width, and a bone core biopsy was obtained. The mean horizontal ridge gain was 1.2 mm across sites, and every site gained width.

One of the most challenging tasks in implant dentistry is to fulfill the esthetic expectations of patients. While implant positioning and adequate amounts of soft and hard tissues are essential for achieving an esthetic outcome, the emergence profile of an abutment/restoration also plays an important role in the definitive appearance of implant prostheses. Therefore, the purpose of this paper is to propose a clinical guideline for designing an abutment/prosthesis based on implant position. By customizing the emergence profile, the overlying soft tissues could be properly contoured and maintained, and pleasing implant prostheses could be achieved.

The purpose of this study was to analyze clinical and radiographic outcomes of sintered porous-surfaced dental implants placed in partially edentulous posterior maxillae. The study group consisted of 42 partially edentulous patients who received sinus augmentation using the lateral window technique or crestal approach at Catholic University Hospital of Daegu and one private clinic. The 42 patients received a total of 92 sintered porous-surfaced dental implants in the edentulous posterior maxillae. All implants were restored with fixed prostheses. Of the 92 implants, 17 implants were restored with individual (nonsplinted) crowns, while 75 implants were splinted to other implants. Panoramic views and periapical radiographs using the standardized long-cone paralleling technique were taken at the first visit, postoperatively, at the time of prosthesis seating, and at a follow-up visit. Survival rates of implants in relation to location, length, diameter, crown-to-implant (C/I) ratio, and type of prosthesis were investigated. Statistical data were analyzed using software with the chi-square test. Of the 92 implants, 8 (8.7%) were removed, and the cumulative survival rate was 91.3% after a maximum 9-year functional period (mean: 72.8 months; range: 11 to 107 months). There were no statistical differences in relation to the location of implants, C/I ratio, or type of prosthesis. However, there were statistical differences in relation to the length and diameter of implants. Average crestal bone loss was 0.68 mm at 1-year follow-up and 1.13 mm at final examination. All implants were inserted in the augmented maxillary sites. The cumulative survival rate of sintered poroussurfaced implants in posterior maxillae was 91.3%. Sintered porous-surfaced implants showed satisfactory results in the edentulous posterior maxillae.

Esthetic parameters in elder patients are essential in esthetic oral rehabilitation. To date, no study has quantified the amount and frequency of soft tissue display in the papilla area in patients over 50 years of age. Photographic examination of 42 fully dentate patients with a mean age of 59 years was performed during enjoyment smile. Digital processing and measurement of the tooth, gingiva, and papilla display revealed that over 90% of subjects displayed soft tissue in the papilla area of the anterior teeth and first premolar during enjoyment smile regardless of their sex. The frequency of the display in descending order follows: maxillary lateral incisor (96%), central incisor (94%), canine (94%), first premolar (91%), second premolar (85%), and first molar (39 %). The mean amount of papilla display was 3.4 mm (0 to 10 mm). There was no significant difference in the amount of papilla display between sexes for anterior teeth, premolars, or first molar (P = .97, P = .79, and P = .48, respectively). Elder Caucasians showed significantly less gingiva in the area of the premolars and molars but not in the anterior region. The amount of papilla display is significantly less in elder Caucasians in the anterior and premolar region. The mean amount of soft tissue display decreased with age but the frequency of papilla display was more than 90% in the anterior region and greater than 70% in the premolar region, suggesting that pink esthetics is an issue in patients over 50 years of age.

The loss of the buccal alveolar plate following tooth extraction in the maxillary anterior region is an especially challenging condition for the clinician. Immediate implant placement with a flapless approach has been suggested in order to reduce postextraction bone loss. In the presence of a significant vertical gap in the buccal plate after tooth extraction, most authors still recommend a bone augmentation procedure before implant placement. In these reports, buccal bone plate regeneration was obtained through a flapless approach and immediate postextraction implant placement with a cancellous bone and collagen graft in the buccal gap.

This study was performed to evaluate the occlusal morphologic similarities between virtually reconstructed full crowns and original natural teeth. A total of 40 stone cast sets with untreated first molars (22 maxillary and 18 mandibular) were scanned and saved as three-dimensional virtual models. The 40 first molars on the stone casts were prepared for all-ceramic restorations, scanned again, and virtually restored with a full veneer crown using a biogeneric tooth algorithm. For comparison of original and virtually restored teeth, orthographic measurements were performed on the cusp tip configurations from the central pits. The measurements were compared using the concordance correlation coefficient (CCC). For maxillary molars, the ranges of CCC were 0.040 to 0.566 in linear, 0.127 to 0.509 in area, and -0.114 to 0.327 in angular measurements. For mandibular molars, the ranges of CCC were 0.104 to 0.555 in linear, 0.183 to 0.597 in area, and 0.030 to 0.396 in angular measurements. The reproducibility of automatic occlusal construction was relatively low. There is a need for improvement in the biogeneric tooth algorithms to enhance the accuracy of restoring to the original occlusal tooth form in cases of full veneer crown preparation.

The extracellular matrix is a complex integrated system responsible for the physiologic properties of connective tissue. Collagen is the major extracellular component that is altered in pathologic conditions, mainly periodontitis. The destruction involves proteolytic enzymes, primarily matrix metalloproteinases (MMPs), which play a key role in mediating and regulating the connective tissue destruction in periodontitis. The study group included 40 patients with clinically diagnosed chronic periodontitis. The control group included 20 patients with clinically normal gingiva covering impacted third molars undergoing extraction or in areas where crown-lengthening procedures were performed. MMP-13 expression was demonstrated using immunohistochemistry in all the gingival biopsies, and the data were analyzed statistically. MMP-13 expression was observed more in chronic periodontitis when compared with normal gingiva. MMP-13 expression was expressed by fibroblasts, lymphocytes, macrophages, plasma cells, and basal cells of the sulcular epithelium. Comparative evaluation of all the clinical and histologic parameters with MMP-13 expression showed high statistical significance with Spearman correlation coefficient. Elevated levels of MMP-13 may play a role in the pathogenesis of chronic periodontitis. There is a direct correlation of increased expression of MMP-13 with various clinical and histologic parameters in disease severity.