Nonsurgical management of soft tissue deficiencies for anterior single implant-supported restorations: A clinical report

Colour thresholds of the gingival chromatic space

OBJECTIVE

To establish the thresholds of chromatic perception and clinical acceptability of gingival colour according to professional category and in accordance with the perceptibility/acceptability threshold of 50:50 (colour differences that can be perceived/accepted by 50 % of the observers).

METHODS

A total of 21 different coloured samples made of pink gingiva Heraceram porcelain were used. Dentists (n = 54), dental assistants (n = 56), dental students (n = 126) and participants unrelated to dentistry (n = 116) were asked to identify pairs of samples that appeared identical. In addition, they were asked to indicate the pairs of samples whose colour they considered to be acceptable for use in a dental rehabilitation. A least squares regression was adjusted using an S-shaped curve of the equation y = exp (B0 + B1/x). The adjusted model was used to predict a colour difference value for an acceptability percentage of 50 %.

RESULTS

The threshold value for the perception of colour changes in human gingiva varies from ΔEab* 2.3 ± 0.38 units and CIEDE2000 (ΔE00) 1.5 ± 0.28units (dental students) to ΔEab* 2.7 ± 0.43 units and ΔE00 1.8 ± 0.30 units (participants unrelated to dentistry). The threshold of gingival acceptability varies from ΔEab* 2.9 ± 0.43 units and ΔE00 2.0 ± 0.31 units (dental assistants) to ΔEab* 3.6 ± 0.54 units and ΔE00 2.5 ± 0.41 units (dental students).

CONCLUSION

From the total number of samples, the average threshold of perception for the gingival chromatic space is 3.1 units for ΔEab* and 2.1 units for ΔE00. Moreover, the mean gingival acceptance threshold is 4.1 units for ΔEab* and 2.9 units for ΔE00. These thresholds are similar for all professional categories studied.

CLINICAL SIGNIFICANCE

The determination of the perception and acceptability thresholds in the gingival chromatic space are of special relevance for designing the physical shade tabs used in gingival colour guides. The results from this work will aid in selecting optimal gingival colour for patients.

Interdisciplinary interface between fixed prosthodontics and periodontics

Although periodontal factors do not usually have a direct effect on the survival of a fixed prosthesis, harmony between the prosthesis and the periodontium is critical otherwise esthetics, the longevity of the prosthesis and the periodontium will be compromised. A close interdisciplinary relationship between periodontics and prosthodontics is therefore necessary to avoid an unsatisfactory treatment outcome, requiring extensive and expensive retreatment. The design of the prosthesis, the number and quality of the abutment teeth, the preparation and the pontic, the occlusion and the material need to be considered when planning prosthodontic treatment. The location of the preparation margin and the contour and emergence profile of the prosthesis will influence the response of the gingival tissues to the prosthesis. Pontic design and cleansibility also contribute to the response of the gingival tissues as well as to the clinical and esthetic outcome. Even an optimal pontic design will not prevent inflammation of the mucosa adjacent to the pontic if pontic hygiene is not maintained by removal of plaque. Case selection and the patients' ability to carry out adequate oral hygiene are therefore essential for longevity of the prosthesis, and regular reviews provide an opportunity for early detection and treatment of failures.

Shear bond strength of a denture base acrylic resin and gingiva-colored indirect composite material to zirconia ceramics

PURPOSE

To evaluate the shear bond strengths of two gingiva-colored materials (an indirect composite material and a denture base acrylic resin) to zirconia ceramics and determine the effects of surface treatment with various priming agents.

METHODS

A gingiva-colored indirect composite material (CER) or denture base acrylic resin (PAL) was bonded to zirconia disks with unpriming (UP) or one of seven priming agents (n=11 each), namely, Alloy Primer (ALP), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Act), Metal Link (MEL), Meta Fast Bonding Liner (MFB), MR. bond (MRB), and V-Primer (VPR). Shear bond strength was determined before and after 5000 thermocycles. The data were analyzed with the Kruskal-Wallis test and Steel-Dwass test.

RESULTS

The mean pre-/post-thermalcycling bond strengths were 1.0-14.1MPa/0.1-12.1MPa for the CER specimen and 0.9-30.2MPa/0.1-11.1MPa for the PAL specimen. For the CER specimen, the ALP, CPB, and CPB+Act groups had significantly higher bond strengths among the eight groups, at both 0 and 5000 thermocycles. For the PAL specimen, shear bond strength was significantly lower after thermalcycling in all groups tested. After 5000 thermocycles, bond strengths were significantly higher in the CPB and CPB+Act groups than in the other groups.

CONCLUSIONS

For the PAL specimens, bond strengths were significantly lower after thermalcycling in all groups tested. The MDP functional monomer improved bonding of a gingiva-colored indirect composite material and denture base acrylic resin to zirconia ceramics.

Prosthetic management of malpositioned implant using custom cast abutment

Two cases are reported with malpositioned implants. Both the implants were placed 6-7 months back. They had osseointegrated well with the surrounding bone. However, they presented severe facial inclination. Case I was restored with custom cast abutment with an auto polymerizing acrylic gingival veneer. Case II was restored with custom cast UCLA type plastic implant abutment. Ceramic was directly fired on the custom cast abutments. The dual treatment strategy resulted in functional and esthetic restorations despite facial malposition of the implants.

Esthetic failure in implant dentistry

The definition of failure for dental implants has evolved from lack of osseointegration to increased concern for other aspects, such as esthetics. However, esthetic failure in implant dentistry has not been well defined. Although multiple esthetic indices have been validated for objectively evaluating clinical outcomes, including failure of an implant-supported crown, only one author has determined a failure threshold. On the basis of objective indices, esthetic failures in implant dentistry can be categorized as pink-tissue failures and white-tissue failures. This article discusses esthetic failures, the factors involved in these failures, and their prevention and treatment.

A focus on soft tissue in dental implantology

Most of the focus in the early dental implant literature is on the bone to titanium interface because a successful Osseo integrated implant requires direct bone contact to the implant surface. The importance of soft tissue in the ability of dental implants to restore function and esthetics has often been underestimated. This paper reviews the pertinent literature on soft tissue healing and management in partially edentulous dental implant patients. Patients seek treatment to replace missing teeth and to improve comfort, function and/or esthetics. Healing around dental implants is affected by the patient's health, soft and hard tissue contours, and the use and care of the prosthesis, surgical augmentation and placement, and the design of the definitive prosthesis. Several surgical and non-surgical procedures have been proposed to treat the soft tissue deformities in the interproximal areas. This review also discusses the interdental papilla and various approaches to preserve and restore the same. Most of the research was based on scientifically legitimate sources of information obtained from primary literature, other appropriate technical references and searching using various online resources.

The effect of different surface treatments on the bond strength of a gingiva-colored indirect composite veneering material to three implant framework materials

OBJECTIVES

To evaluate and compare the shear-bond strength of a gingiva-colored indirect composite material to three different implant framework materials (zirconia ceramics, gold alloy, and titanium), and to investigate the effect of surface pretreatment by air-particle abrasion and four priming agents.

MATERIAL AND METHODS

A gingiva-colored indirect composite (Ceramage) was bonded to three framework materials (n = 80): commercially pure titanium (CP- Ti ), ADA (American Dental Association)-type 4 casting gold alloy (Type IV), and zirconia ceramics (Zirconia) with or without airborne-particle abrasion. Before bonding, the surface of the specimens was treated using no (control) or one of four priming agents: Alloy Primer (ALP), Estenia Opaque Primer (EOP), Metal Link Primer (MLP), and V-Primer (VPR). Shear-bond strength was determined after 24-h wet storage. Data were analyzed using Steel-Dwass for multiple comparisons, and Mann-Whitney U-test (P = 0.05).

RESULTS

For both CP- Ti and Zirconia substrates, three groups, ALP, EOP, and MLP, showed significantly higher bond strengths (P < 0.05) than the other groups with or without airborne-particle abrasion. For Type IV substrates, significantly higher bond strengths were obtained in ALP and MLP groups (P < 0.01) compared with the other groups with airborne-particle abrasion.

CONCLUSIONS

Application of priming agents containing specific phosphoric ester groups significantly enhances the bond strength of a gingiva-colored composite material to commercially pure titanium and zirconia frameworks. Combined use of a thione monomer with a phosphoric monomer enhances the bond strengths to airborne-particle abraded type IV gold alloy.

Implant esthetic restoration in ridge deficiencies in cases of trauma: a case report

The long-term success of implant therapy does not depend solely on osseointegration, but the gingival architecture surrounding the implant system. It becomes very important to restore the gingival tissues in the areas that enhance one's esthetics. The esthetic zone can be defined as any dentoalveolar area of esthetic concern to the patient. The anterior maxillary teeth in the esthetic zone usually extend from first premolar to first premolar, but in some individuals can extend as far distally as the first molar. The patients requiring esthetic reconstruction at the site of trauma pose a great problem in implant placement and prosthetic restoration as scar tissue interferes with the same. To be successful, an implant-supported restoration should meet biological, mechanical, and esthetic goals. The most challenging situation is when esthetics is of prime concern in deficient ridge cases. This clinical report presents problems faced during implant placement and the sequential procedure to rehabilitate with an implant that was esthetically harmonized at the site of trauma.

Screwless Fixed Detachable Partial Overdenture Treatment for Atrophic Partial Edentulism of the Anterior Maxilla

This is a case report of the restoration of a partially edentulous atrophic anterior maxilla and atrophic mandibular posterior ridges. This case report demonstrates one method for successful treatment of partial edentulism at No. 7 to 10, where interlock attachments on natural cuspids and mini dental implants support an acrylic-based screwless fixed detachable partial denture to provide lip support and masticatory function in the anterior maxilla. The presenting qualities of this case were similar to combination syndrome.