Gingival Shade Research Articles

Level of Agreement in Subjective Selection of Gingival Colour

Background and Objectives: Primary outcome: To assess the level of agreement between the objective and subjective methods for recording gingival colour in each area of the gingiva. Secondary outcome: To compare performance of the subjective visual method of gingival colour selection by a male observer and a female observer. Materials and Methods: A chromatic study was conducted on a total of 101 participants, in five gingival zones, from the free gingival margin to the mucogingival line, using a SpectroShade Micro spectrophotometer for the objective method and 21 ad hoc ceramic gingival shade tabs for the subjective method. A man and a woman of the same age, with the same amount of clinical experience in dentistry, selected the tab that most resembled the colour of participants’ gingiva. The “chromatic error” was then assessed by calculating the colour difference (using the Euclidean and CIEDE2000 formulae) between the CIELAB coordinates of the shade tab selected and the objective coordinates of the gingiva. The unweighted Kappa coefficient was used to calculate the level of agreement between observers. Results: For the male observer, the mean chromatic errors varied between ΔEab* 10.3 and 13.1 units, while for the female observer, the mean errors varied between ΔEab* 11.1 and 12.8: these differences were not statistically significant. Similarly, no statistically significant differences were found between the mean chromatic errors for the five gingival zones in either the male operator (p = 0.100) or the female operator (p = 0.093). The minimum level of agreement (unweighted Kappa) between the observers ranged from 0.1 to 0.4. Conclusions: Subjective selection of gingival colour was very inaccurate, by both the male observer and the female observer, for any area of the gingiva, with no differences identified between them. The level of agreement between the observers was low. These findings suggest that gingival colour should not be determined using solely subjective methods, given that the chromatic errors significantly exceeded the clinical acceptability threshold for gingiva (4.1 units for ΔEab* and 2.9 units for ΔE00). Both observers showed a tendency to select gingival shade tabs that were redder and bluer than the objective colours.

Exploring Digital Gingival Shade Matching in Students.

To study the degree of accuracy in gingival shade matching of undergraduate students using a computer application. In total, 76 undergraduate dental students' gingival shade selection abilities were evaluated using an in-house developed computer application. A total of 15 intraoral gingival photographs and 21 pink gingival color porcelain samples were used. The environmental conditions were standardized, and no time limit was set for answering in the computer application. Fourteen gingival color samples (66.6%) were not useful for representing the studied gingival shades. Not all natural gingival colors studied were represented within the 50.50% acceptability limits of the pink samples. There were no statistically significant differences between men and women in terms of "hit" percentages. The highest correlation coefficient (in absolute value) was for the L* coordinate (the darker the gingiva in the picture, the higher the hit rate for choosing the "ideal" shade tab); however, none of the linear correlation coefficients were statistically significant. Not all colors provided in the pink ceramic system were useful for subjective gingival selection. There were no statistically significant differences between male and female dental students in gingival color perception. The L* coordinate was the only one that influenced the correct perception of gingival color by dental students, and it did so more in women than in men.

Degree of Standardisation in Ceramic Gingival Systems.

No gingival shade guide exists that can be used as a 'gold standard' in gingival shade selection. This research, therefore, aimed to determine whether comparable results in subjective gingival shade selection can be achieved using basic gingival colours produced by distinct manufacturers. It also aimed to explore how coverage of the colour space is affected by mixing these basic colours to create additional shades. To achieve these objectives, the basic gingival colours of three ceramic systems (Heraceram, Kulzer, Madrid, Spain; Vita VM9, Vita Zahnfabrik, Bad Säckingen, Germany; IPS Style, Ivoclar, Schaan, Liechtenstein) were analysed. The colour systems were expanded by creating porcelain gingival samples, whose colours were obtained by mixing the basic colours, altering each mixture by increments of 10%, and respecting the numerical order used by manufacturers to identify the colours. The colour coordinates of the basic and additional colours were recorded using spectrophotometry, and the intra- and inter-system colour differences were calculated using the Euclidean (ΔEab) and CIEDE2000 (ΔE00) formulae. None of the basic colours in the three systems, despite their similar nomenclature, were found to be interchangeable (the colour differences exceeded the gingival acceptability threshold: ΔE00 2.9 units). The expanded gingival colour systems, with mixtures altered by 10% increments, notably increased the gingival colour space covered by the original systems. The authors concluded that there are clear differences between the basic gingival colours produced by distinct manufacturers using the same nomenclature. Ceramic samples produced by mixing basic gingival colours are a resource with the potential to improve subjective gingival shade matching.

Fifteen ceramic gingival samples: A proposed gingival shade guide

Objective(1) To put forward a set of valid pink ceramic samples for subjective gingival colour selection in the Caucasian population, and (2) to assess the quality of the shade matches provided by the selected pink samples. MethodsThe ceramic gingival shade samples (n = 133) were obtained by mixing pairs of basic colours from a single system. In each mixture, the proportions of the colours were altered in 10% increments, following the numerical order used by the manufacturers of the three colour systems under study (Heraceram, Vita VM9 and IPS Style). The CIELAB colour coordinates were recorded using spectrophotometry in three zones of healthy anterior gingiva (n = 360). The sample was randomly divided into two subsamples, each of which contained 180 participants. Subsample 1 was used to select the ceramic gingival samples that provided the best shade matches, using the k-means clustering method. Subsample 2 was used to assess the chromatic validity of the selected gingival samples, according to the coverage error. ResultsTo identify the ceramic gingival samples that best represented participants’ gingival colour, the minimum colour differences (ΔEab∗, ΔE00) between the cluster centroids and the 133 gingival samples were calculated. Fifteen gingival samples were selected: 8 from the Heraceram system, 4 from the VM9 system, and 3 from the IPS Style system. Coverage errors for the 15 gingival samples fell below the gingival clinical acceptability thresholds in the three gingival zones examined. ConclusionsThe 15 ceramic gingival colour samples provide satisfactory coverage of the gingival colour space, with coverage errors below the ΔE00 clinical acceptability threshold of 2.9 units. These pink colour samples have the potential to provide good gingival shade matches in subjective colour selection. Clinical SignificanceMixing basic ceramic colours is a viable method for generating a series of pink shades that can be used as a physical gingival shade guide. The resulting guide provides valid results (under the acceptability thresholds) for subjective selection gingival colour selection in clinical practice.

Assessment of Prevalent Gingival Shades in the South Indian Population: An Observational Study.

Gingival shade matching, often overlooked, plays an integral role in designing prostheses for patients with high smile lines, gingival defects, and cases where the acrylic flange of removable dentures extends into the aesthetic zone.The purpose of this study was to find the most prevalent gingival shade in a sample of the South Indian population. A total of 110 participants were included in the study based on the inclusion and exclusion criteria. The standard daylight method of shade matching was used for this study. The participants were seated in a dental chair in the vertical position with their heads supported, their mouths open, and cheek retractors in place. The study area, gingiva, and vestibular region in relation to maxillary and mandibular right central incisors were dried with a three-way syringe, 15cm away, for 3 seconds before shade matching for 5 seconds at each reference point with an Ivoclar Vivadent IPS Dsign shade guide. The most prevalent shade in the marginal and vestibular regions of the gingiva of the South Indian population was found to be GM2 shade, while the most prevalent shade of the attached gingiva was found to be G2 shade. A good percentage of the attached gingival shade was not matched with the tabs available in this shade guide.

Study of attached gingiva space color according to gender and age in Caucasian population.

To describe the color of the healthy attached gingiva adjacent to the maxillary incisors and to evaluate the effect of age and gender on CIELAB color coordinates. The study included 216 Caucasian individuals (129 females and 87 males) divided into three age groups. A SpectroShade Micro spectrophotometer was used to register color coordinates at 2.5 mm apical of the zenith of the upper central incisors. Descriptive and inferential statistical analysis was performed. The minimum and maximum coordinates in which the CIELAB natural gingival space is delimited are: L* minimum 40.4 - L* maximum 61.2; a* minimum 17.0 - a* maximum 30.2; b* minimum 9.8 - and b* maximum 21.9. There are statistically significant differences between males and females for coordinates L*, a* and b* in the attached gingival area selected. Age had a significant effect on coordinate b* (p=0.000). Statistically significant differences were found between the L*, a* and b* color coordinates of the attached gingiva between men and women, although the color difference is below the clinical acceptance threshold. The attached gingiva takes on a bluish color as the patients get older, which means that the b* coordinate decreases. With a prosthodontic approach, knowledge of the CIELAB natural attached gingival coordinates based on the patient's age and gender will facilitate the clinician's work in selecting the appropriate color. The CIELAB system values found can be used as a gingival shade guide reference.

CIEDE2000 lightness, chroma and hue human gingiva thresholds

Objective: To determine the visual 50:50% perceptibility and acceptability CIEDE2000 lightness, chroma and hue human gingiva thresholds. Methods: A psychophysical experiment based on visual assessments of simulated images of human gingiva on a calibrated display was performed. A 20-obsever panel (dentists and laypersons; n=10) evaluated three subsets of simulated human gingiva: lightness subset (|ΔL′/ΔE00|≥ 0.98); chroma subset (|ΔC′/ΔE00|≥ 0.98) and hue subset (|ΔH′/ΔE00|≥ 0.96) using ΔE00< 5 units. A Takagi-Sugeno-Kang (TSK) Fuzzy Approximation model was used as fitting procedure, and 50:50% perceptibility threshold (PT) and acceptability threshold (AT) were calculated. Data was statistically analyzed using t-test (p ≤ 0.05). Results: The 50:50% PT were ΔL’ = 0.74 (95% confidence interval (CI) 0.39−1.09); ΔC’ = 1.10 (95% CI 0.57−1.46); ΔH’ = 2.40 (95% CI 1.66->3.85). The 50:50% AT were ΔL’ = 2.57 (95% CI 2.00−3.06); ΔC’ = 2.70 (95% CI 2.19−3.38). AT ΔH’ may be considered no computable. PT values were statistically significant among the three metric differences (p ≤ 0.05). No difference was found between observers for PT values. Conclusions: Statistically differences in perceptual limit were found among hue, lightness and chroma for human gingiva. Thus, the observers seem to show lower sensitivity for changes in hue (ΔH′) than in chroma (ΔC′) and in lightness (ΔL′) in the gingiva color space. Clinical significance: PT and AT for lightness, chroma and hue specific for human gingiva should be used when evaluating natural gingiva, pink gingival shade guides or pink materials, since the thresholds of perception and acceptability for teeth are not suitable.

Chromatic Compatibility of Two Gingival Shade Guides with Human Keratinized Gingiva

To measure the validity and reliability of two gingival shade guides to represent in vivo gingival color using a Caucasian population sample. CIELab color space was used to study three gingival reference areas (the free gingival margin, the keratinized gingival body, and the upper part of the keratinized gingiva) in a sample of 259 Caucasian individuals. The color coordinates on the HeraCeram and on the IPS d.SIGN physical gingival shade guides were collected to compare with the color coordinates taken in vivo. The coverage errors of the two shade guides evaluated were calculated using CIELab, and CIEDE 2000 formula and each area of the gingiva was compared with the 50:50% acceptability threshold for ΔE* = 4.6 and ΔE00* = 4.1. The spectroshade spectrophotometer was used. The IPS d.SIGN guide has similar coverage errors in all three areas and, in all cases, surpasses the 50:50% acceptability threshold. In contrast, the HeraCeram Gingiva guide has a lower coverage error in the free gingival margin than in the other two areas, and the coverage error remains below the 50:50% acceptability threshold only for δE00*. The HeraCeram gingiva shade guide has overall coverage errors (ΔE* = 7.9 and ΔE00* = 5.6) significantly lower than the coverage errors obtained for the IPS d.SIGN gingival shade guide (ΔE* = 9.2 and ΔE00* = 6.8). Statistically significant differences were found in the coverage errors of both guides, both at the level of the three reference areas and at the global level. For both guides and in both sexes, the global coverage errors calculated with the CIELab and CIEDE2000 formulas were below the literature data on 50:50 acceptability thresholds.

Proposal for a gingival shade guide based on in vivo spectrophotometric measurements.

PURPOSEThe purpose of this study was to propose and assess a shade guide for pink gingival aesthetics using a Spanish population sample.MATERIALS AND METHODSThe L*, C*, h, a* and b* coordinates of 259 participants were measured using a spectrophotometer in 3 standardized points along the attached gingiva of the maxillary central incisors. A hierarchical clustering analysis was applied to obtain separate solutions regarding the number of shade tabs. For each of the solutions obtained, color differences (ΔE*) were calculated using the CIELab and CIEDE2000 formulas, and the proposed shade guide was selected considering (1) the color differences between tabs and (2) the coverage error of each of the solutions.RESULTSThe proposed shade guide consisted of 8 gingival shade tabs and achieved CIELab and CIEDE2000 coverage errors of less than the respective 50:50% acceptability thresholds (ΔE*=4.6 units and ΔE00=4.1). The coordinates for the various gingival shade tabs were as follows: Tab 1: L*43.3, a*21.9, b*12.3 (1.6); Tab 2: L*42.9, a*34.1, b*19.1; Tab 3: L*46.5, a*25.8, b*10.9; Tab 4: L*46.5, a*27.3, b*15.1; Tab 5: L*49.6, a*23.5, b*16.8; Tab 6: L*51.5, a*19.7, b*13.6; Tab 7: L*55.9, a*22.0, b* 15.0; and Tab 8: L*56.0, a*19.9, b*18.8.CONCLUSIONThe CIELab and CIEDE2000 coverage errors for the 8 shade tabs of the proposed gingival shade guide were significantly lower than those of other guides. Therefore, despite the limitations of this study, the proposed guide is more appropriate for matching gingival shade in the Spanish general population.

Color Compatibility of Gingival Shade Guides and Gingiva-Colored Dental Materials with Healthy Human Gingiva.

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.

Gingival shade guides: Colorimetric and spectral modeling.

To design colorimetric and spectral models of gingival shade guides that adequately represent the color of human gingiva. A previously compiled database on the spectral reflectance of healthy keratinized gingiva was used for optimization. Coverage Error (CE) and Maximal Error (ME) were optimized using CIELAB and CIEDE2000 color difference formulas. A two-phase process included an FCM algorithm and a nonlinear optimization. A t test was used to compare the performance of the different numbers of clusters/tabs in gingival shade guide models (α = .05). CIELAB CE and ME for shade guide models with 3 to 6 clusters ranged from 3.1 to 3.9 (P = .028 for 3 vs. 4; and P = .033 for 5 vs. 6 cluster/tab comparison), while the corresponding CIEDE2000 range was from 2.1 to 2.8 (P < .001 for 3 vs. 4 tabs; P < .025 for 4 vs. 5; and P = 0.029 for 5 vs. 6 tab comparisons). The percentage of data points exhibiting a CIELAB color difference lower than the acceptability threshold ranged from 48.7% to 71.4%, and from 52.9% to 82.4%. for CIEDE2000. An increase in the number of clusters in the gingival shade guide models was associated with a decrease in coverage error (better match) to human gingiva. Gingival shade guide models with only 4 tabs provided a CIELAB and CIEDE2000 coverage error lower than the acceptability threshold for gingival color. Spectral clustering of human gingiva was determined to be valid. CIEDE2000 color difference formula outperformed the CIELAB formula in the optimization process. Providing a shade guide model with a small number of tabs and a coverage error lower than the 50:50% acceptability threshold would be an optimal solution for shade matching in dentistry. However, no actual gingival or tooth shade guide complies with this. The clustering method, with optimization of both Coverage Error and Maximal Error and spectral clustering that enables more reliable color formulation of cluster representatives of shade guide models, represents an advance when it comes to computer modeling in dentistry.

Technique to Match Gingival Shade when Using Pink Ceramics for Anterior Fixed Implant Prostheses

Use of pink gingival ceramics can reduce the necessity for extensive surgical procedures attempting to restore missing soft and hard tissues in the maxillary esthetic zone. Selecting the appropriate shade for pink porcelain poses a challenge, especially when the patient presents with a high smile line. This paper describes a simple and effective technique to facilitate shade selection for gingival ceramics to match the patient's existing gingival shade.

Innovative Method of Conservative Aesthetic Treatment for Gingival Recession.

A 50-year-old male patient reported to the OPD of Desh Bhagat Dental College and Hospital, Muktsar, Punjab with a chief complaint of sensitivity to cold in all the teeth. Upon clinical examination generalised gingival recession was seen in upper and lower arch from first molar of one side to the first molar of other side. On taking detailed history, the etiology of recession was found to be faulty tooth brushing technique. Various treatment modalities were considered to treat the same. It was finally decided to use an innovative method to restore teeth by adding ceramic tints to traditional composite resin. Pre operative photograph of patient was taken [Table/Fig-1]. Then gingival shade was determined with the help of Vita Akzent shade guide [Table/Fig-2]. After that ceramic tint powder (no. 703 and 704, Vita GmbH and Co. KG Germany) was taken in a well to match the shade of gingiva. Only 1-2 drops of dentin bonding agent were added to dissolve the ceramic tint in it. Composite resin material of selected shade was added to the mixture; till a thick paste consistency was achieved [Table/Fig-3]. Then the teeth were etched with 37% phosphoric acid [Table/Fig-4] following which bonding agent was applied and cured [Table/Fig-5]. The composite resin with ceramic tint was then applied and final curing was done followed by finishing and polishing [Table/Fig- 6]. Gingival recession is a commonly encountered problem in routine dental practice. It is more prevalent in older people and in males as compared to females [1]. Main etiological factors for gingival recession are periodontal diseases, mechanical forces such as occlusal trauma and aggressive use of tooth brush, iatrogenic factors such as orthodontic treatment and subgingival crown preparations and anatomical factors such as tooth position, high frenum attachment etc., [2]. Malpositioned teeth and toothbrush trauma are major contributing factors to gingival recession [1]. Various treatment modalities have been proposed for treating gingival recession [3]. These can be broadly classified into: [Table/Fig-1]: Pre operative photograph showing generalized gingival recession. [Table/Fig-2]: Matching the shade of gingiva with shade guide. [Table/Fig-3]: Mixing the colored bonding agent to conventional composite. [Table/Fig-4]: Etching of teeth. [Table/Fig-5]: Bonding agent application. [Table/Fig-6]: Immediate post operative photograph.

Factors involved in the spectrophotometric measurement of soft tissue: A clinical study of interrater and intrarater reliability

Statement of problemThe reliability of spectrophotometric measurements of gingival color has not been tested. PurposeThe purpose of this study was to evaluate the repeatability and reproducibility of gingival color measurements with a digital spectrophotometer. Measurement error was estimated by determining the interrater agreement and by repeating measurements in different illumination environments with and without contact of the device with the gingiva. Material and methodsTwo trained examiners measured the gingival shade around 30 central incisors with a spectrophotometer with and without external illumination and with and without contact of the device with the gingiva. Color data obtained (CIELab color coordinates; L*, c*, h*, a*, b*) were analyzed with the intraclass correlation coefficient (ICC) and the Student t test for paired samples. ResultsMean L*, c*, a*, and b* values differed significantly between measurements made with and without contact of the device with the tissue, but no difference was found in h* values. An ICC of >0.9 was obtained for interrater and intrarater agreements in all cases. Shade measurements did not differ between the presence and absence of stable ambient light. ConclusionsThe repeatability and reproducibility of soft tissue shade measurements were almost perfect (ICC >0.9) under the examination conditions tested. The measurements were affected by pressure but not by ambient light.

Proposed shade guide for attached gingiva--a pilot study.

The purpose of this study was to evaluate the effect of race, age, and gender on Commision Internationale de l'Eclairage Lab color space (CIELAB) values of attached gingival colors. The color coordinates of an optimal proposed attached gingival shade guide were also determined. Participants (n = 120) were recruited to fulfill the following stratification of five age groups: 18-29, 30-39, 40-49, 50-59, and 60-85, with four racial categories (white, black, Asian, and others) and balanced for gender. Reflectance measurements of participants' attached gingiva were made using a spectroradiometer and Xenon arc lamp with a 45/0 optical configuration. A stepwise discriminant analysis was carried out to identify gingival color contribution from race, age, and gender. A hierarchical clustering analysis was used to identify color groups that clustered together. The coverage error of the proposed shade guide was calculated to the original gingival color. The stepwise discriminant analysis showed a statistically significant difference in gingival color contribution from the factors evaluated. Significant influence was found for the race/gender factors (p < 0.05), but not for age. The cluster analysis results revealed three cluster centroids with mean L*a*b* as follows: (1 = 51.0 ± 4.2, 27.7 ± 4.7, 18.3 ± 3.2), (2 = 61.4 ± 4.5, 24.3 ± 4.3, 17.6 ± 2.3), and (3 = 36.1 ± 4.1, 21 ± 4.9, 16 ± 5.2). The coverage errors to the following racial categories were: Asian (ΔE = 6.0 ± 4.8), black (ΔE = 6.7 ± 3.9), others (ΔE = 5.8 ± 2.9), and white (ΔE = 4.6 ± 2.7). The study showed that L*a*b* was significantly affected by race and gender. Clustering analysis was able to identify clusters in 120 participants for three gingival tones.

Esthetically improved complete denture by gingival shade alteration: a case report

cc 2014 The Korean Academy of Prosthodontics This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. *Corresponding Author: Jee-Hwan Kim Department of Prosthodontics, School of Dentistry, Yonsei University, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Republic of Korea +82 2 2228 3161: e-mail, jee917@yuhs.ac Article history: Received 23 June, 2014 / Last Revision 7 July, 2014 / Accepted 10 July, 2014 서론

Esthetically improved complete denture by gingival shade alteration: a case report

Esthetically improved complete denture by gingival shade alteration: a case report

Implant restoration considering maintenance for a patient with excessive crown height space

Complications increases when crown height space is excessive and one should be careful of choosing type of fixed prosthesis in case crown height space is over 12 mm. In this condition, tooth seems to be longer, therefore, it is needed to use gingival shade in aesthetically important area for fixed prosthesis. In this case, fixed prosthesis which has inappropriate maintenance and hygiene could hold food, plaque, calculus, thus increase incidence of inflammation and infection. Moreover, it could lead to chronic inflammation and infection and in that case surgical improvement could be necessary. In present case report, gingival inflammation and swelling developed around prosthesis after having made it considering articulation and aesthetic view in patient who had excessive crown height space. Finding out that design of prosthesis is a factor to make it hard to maintain oral hygiene, a temporary prosthesis which has enough interproximal space and proper emergence profile was fabricated. After two months of observation, significant abnormal symptoms are not found and oral reconstruction is performed using fixed prosthesis with zircornia infrastructure and porcelain build-up based on convenient self hygiene design. Through serial treatment, inappropriate soft tissue response is not observed and satisfactory result in functional aspect comes out. (J Korean Acad Prosthodont 2013;51:10712)

Using a spectrophotometric study of human gingival colour distribution to develop a shade guide

ObjectivesFor dental prostheses, colour choice is a main concern. The present spectrometric study analyzes healthy gingiva to develop a shade guide for pink aesthetics. MethodsA reflectance spectrometer and an external light source were set up in a 45/0-degree optical configuration to measure the colour of gingiva over the maxillary anterior area. A total of 362 human subjects with healthy gingiva were divided into groups according to sex and age. The Commission Internationale de l‘Eclairage L*, a*, and b* (CIELAB) values and differences in colour (ΔE) were measured. A two-way analysis of variance (ANOVA) test and cluster analyses were used to analyse the data. ResultsThere are significant differences in the gingival colour by sex (ΔE>3.7). The mean CIE L* value of female gingiva is significantly higher than that of male gingiva (p<0.05). No significant differences were found between age groups. 10 categories for gingival colour are established. ConclusionThe gingival colour of females is lighter than that of males. The proposed colour classification can be used as a gingival shade guide reference by dental laboratory technicians.

Effect of Surface Preparation on the Failure Load of a Highly Filled Composite Resin Bonded to a Denture Base Resin

The purpose of this study was to evaluate the effect of the surface preparation on the maximum fracture load value of a highly filled gingival shade composite resin bonded to a denture base resin. Block specimens were prepared from a heat-processed denture base resin and divided into five groups. The flat surfaces of the specimens were abraded with 400-grit silicon carbide paper, then prepared in one of the following ways: (1) without preparation (group 1); (2) application of silane coupling agent (group 2); (3) application of dichloromethane (group 3); (4) application of dichloromethane following the silane coupling agent (group 4); or (5) tribochemical silica coating (group 5). A highly filled gingival shade composite resin was applied (area diameter= 5 mm) and polymerized with a light polymerizing unit. Specimens made entirely of heat-processed denture base resin were also fabricated as references (group 6). The halves of the specimens of groups 4, 5, and 6 were thermocycled up to 10,000 times in water between 5 degrees C and 55 degrees C with a 1-minute dwell time at each temperature. Shear testing was performed in a universal testing machine at a crosshead speed of 1 mm/min, and the maximum fracture load values were determined (n = 10). The maximum fracture load values of the highly filled gingival shade composite resin bonded to the denture base resin for all preparation groups were significantly enhanced before thermocycling (p < 0.05). Group 5 exhibited the greatest fracture load value, followed by group 4, compared to the other groups (p < 0.05), however, the fracture load values significantly decreased for these groups after thermocycling (p < 0.05), whereas the fracture load value of group 6 did not decrease (p > 0.05). Tribochemical silica coating and the application of dichloromethane after the silane coupling agent were effective surface preparations for the bonding of a highly filled gingival shade composite resin to a denture base resin, however, the bond durability of these treatments may be insufficient.