Introduction
The prevalence of dental trauma is high (ANDREASEN & ANDREASEN 1990; ANDERSSON 2013). Every effort should be made to save and maintain injured permanent teeth (KASTE ET AL. 1996; HAMILTON ET AL. 1997; FLORES ET AL. 2001; KAHLER ET AL. 2016). Traumatically luxated or avulsed permanent teeth need to be repositioned or replanted and stabilized with a splint (BARRET & KENNY 1997; FLORES ET AL. 2001; POHL ET AL. 2005; ANDERSSON ET AL. 2016; DIANGELIS ET AL. 2017). Various trauma splints and splinting techniques are available that achieve more or less good clinical results (OIKARINEN ET AL. 1992; KAHLER ET AL 2016; BEN HASSAN ET AL. 2016). The aim of successful splinting is to support the healing process of the periodontal ligament (PDL) (VON ARX ET AL. 2000; VON ARX ET AL. 2001A; VON ARX ET AL. 2001B; FILIPPI ET AL. 2002; BEN HASSAN ET AL. 2016). To support healing, a splint should have passive and flexible mechanical characteristics that allow physiologic tooth mobility (KRISTERSON & ANDREASEN 1983; OIKARINEN 1990; MAZZOLENI ET AL. 2010; BEN HASSAN ET AL. 2016;). One of the existing splints with good mechanical properties is the Titanium Trauma Splint (TTS) by Medartis? (Basel, Switzerland). As a “low rigidity flexible splint”, the TTS causes very little restriction of mobility and thus enhances the process of periodontal healing (KRISTERSON & ANDREASEN 1983; BERUDE ET AL. 1988; MANDEL 1989; BEN HASSAN ET AL. 2016). The TTS was first introduced 20 years ago; it originally came in a golden matt version; furthermore, it is easy to apply and requires little chairside time (BEN HASSAN ET AL. 2016).
Esthetic demands have increased during the last years (LARSSON 2010; JOINER & LUO 2017), and a dental accident needing splinting of teeth has a considerable esthetic impact to the patient. Previous studies showed that there were other splints with better esthetics, e.g., nylon fishing line splints (BEN HASSAN ET AL 2016).
The TTS achieves good clinical results, but has esthetic disadvantages which impact the patient’s quality of life during splint therapy (VON ARX ET AL. 2001A; FILIPPI ET AL. 2002; BEN HASSAN ET AL. 2016). The reported esthetic impact of the TTS is most probably related its conspicuous color (JOINER & LUO 2017). A characteristic of modern society is the importance placed on a pleasant physical appearance. During interaction between people, two of the first things observed are the eyes and the mouth; therefore, it is logical that the mouth and front teeth are important aspects (SAMORODNITZKY-NAVEH ET AL. 2007; DUDEA ET AL. 2012; NAYAK ET AL. 2019). Splinted teeth often impair a patient’s oral health-related quality of life and personal esthetics during daily life and business (VON ARX ET AL. 2001A; BEN HASSAN ET AL. 2016).
Important parameters for successful treatment are not only clinical parameters but also patient-related satisfaction (HEYDECKE 2002, SPANEMBERG ET AL. 2019). If the treated teeth are not perceived as sufficiently pleasing to the patient’s eye, there can be negative effects such as the patient feeling embarrassed, being unhappy, avoiding smiling and suffering (HEYDECKE 2002; ALKHATIB ET AL. 2004; LARSSON 2010; DUDEA ET AL. 2012; SPANEMBERG ET AL. 2019). To avoid treatment outcomes that cause feelings like this and impair the patient’s quality of life, it’s important to have an esthetically well-accepted treatment option after a dental accident. To improve patient satisfaction during splint therapy in adults, we tested eight different TTS variants in four different colors (gold, silver, violet and green) with two different surface finishes each (matt and polished).
The aim of this study was to evaluate patients’ splint color and surface finish preferences to identify the most preferred TTS variant with the highest optical acceptance rate in order to improve the quality of life of patients during splint therapy.
Materials and Methods
Eight different TTS variants were fabricated (Medartis? Basel, Switzerland) in order to determine which achieved the highest optical acceptance rate in adults. The splint variants differed in color (gold, silver, violet and green) and surface finish (matt or polished) (Figure 1), and were not commercially available at the time of the survey besides the gold polished version. This study was in accordance with the principles of the Declaration of Helsinki and the informed consent was obtained.
Splint preparation and application
Each splint variant was adjusted and preformed on a plaster cast of a single human female’s teeth with composite resin (Tetric Evo Flow A1, Ivoclar Vivadent®, Schaan, Liechtenstein) light-cured with a polymerization lamp (three-point fixation) (Bluephase, Ivoclar Vivadent®, Schaan, Liechtenstein) for 30 seconds, removed from the cast, and placed on the model’s teeth without using new composite or damaging the tooth in any way. Placed like this, each splint was photographed in a standardized manner on the same model (Figure 2). The model was not an actual patient but based on an individual who suffered a dental accident in the past.
The pictures were taken by a professional photographer with a Nikon D700 full-frame body and a 24-70mm f/2.8 lens. The following settings were used for all photographs: focal length 70mm, aperture f9, shutter speed 1/160. The photos were processed with PowerPoint (Microsoft®, Redmond, USA) and printed as 59.4 cm x 84.1 cm posters (DIN A1) showing all eight different splint color (gold, silver, violet and green) and surface finish (matt vs. polished) combinations.
Splint preference questionnaire
Each participant completed a written questionnaire surveying their trauma splint color and surface finish preferences as well as their age, sex, eyesight (color blindness) and opinions regarding the importance of dental esthetics, including questions on previous bleaching treatments, the prioritization of esthetic versus function-driven dental treatment, and the importance of having esthetic teeth in general. Questionnaire items are summarized in Table 1.
The survey was conducted in a single private dental office and completed by 397 people aged between 18 and 79 years. Twenty-five were excluded due to color-blindness or illegible handwriting. The remaining 372 participants consisted of 222 females and 150 males, who were divided into five different age groups for the statistical analysis: 18-30 years, 31-40 years, 41-50 years, 51-60 years and older than 60 years.
Descriptive statistics comprised the mean and standard deviation (SD) of continuous variables as well as the median and interquartile range (IQR) of categorical variables. The following significance tests were also performed as indicated: Student’s t-test, F-test, Fisher's exact test, chi-square test, Wilcoxon rank-sum test and/or Kruskal-Wallis test.
Adjustment for age and gender was accomplished using additional regression models. Variable linear regression models were used in the case of Gaussian distribution of outcomes, and logistic regression models were performed in the case of binary outcome variables. In the case of Poisson-distributed variables, a general linear model was run to allow for over-dispersion of the Poisson distribution. The difference between mean values or odds ratios (OR) was estimated with the corresponding 95% confidence interval (CI) and p-value according to the regression model. A p-value <0.05 was considered significant. No adjustment for multiple comparisons was done due to the descriptive nature of the study. All analyses were performed using the statistical program R (version 3.5.3).
Results
More women (n= 222, 59.7%) participated in the survey than men (n= 150, 40.3%). The group of 31 to 40-year-olds formed the largest group (n=119, 32.0%). Of the 372 participants, 335 (90.1%) preferred the silver splint, and most of them preferred the silver splint with a matt surface. No examined factor (age, previous bleaching treatments, prioritization of function versus esthetic-driven dental treatment, and the importance of having esthetic teeth in general) had a significant influence on color or surface preference. The silver matt splint was the most popular variant (n=306, 82.3%) across all age groups (Table 2). Participants who preferred the matt surface were on average 5 years younger than the mean study population (p= 0.026).
Furthermore, this surface was preferred 2.7 times more by women than men (OR=2.7, p=0.004). In contrast to women, men generally had lower regard for esthetic compared to function-driven treatment (p=0.049) (Table 3). Regarding the importance of having esthetic teeth in general, men found it less important than women (p<0.001).
Discussion
Among researchers and the general population, awareness of the impacts of oral health and anterior esthetics is increasing, and these factors can impact a person’s quality of life in a negative way (HAWLEY ET AL. 1996; ALKHATIB ET AL. 2004; LARSSON 2010; DUDEA ET AL. 2012; SPANEMBERG ET AL. 2019). This study was performed to help to avoid a further decrease of patients’ quality of life due to splinting therapy. The results of our survey showed that silver matt was the most popular TTS variant, and it was the splint with the highest optical acceptance rate. No factor studied had an influence on splint color or surface choice. Our findings also show that women have higher esteem for esthetics than men.
Various splints are available in different materials and have been tested in previous studies (BEN HASSAN ET AL. 2016). These include the wire-composite splint, twist-flex wire, button-bracket splint, resin splint, titanium trauma splint, the single and double fiberglass splint, and the nylon (fishing) line, power chain and other splints (VON ARX ET AL. 2001A; FILIPPI ET AL. 2002; BEN HASSAN ET AL. 2016). Some of them—like the double fiberglass splint—are too stiff to achieve good periodontal healing, and others—like the twist-flex wire—are not easy to apply. The nylon line achieved good results and stiffness characteristics and was found to be the most esthetically pleasing, but was difficult to apply due to its small diameter. Another disadvantage was that it broke easily away from the bonding material, resulting in tooth movement and the need for resplinting (BEN HASSAN ET AL. 2016). Besides esthetics and durability, the need to not have to repeat treatment over and over again is also important for a good quality of life during splint therapy (SPANEMBERG ET AL. 2019). The TTS was shown to achieve good clinical results: due to its low stiffness, it causes relatively little restriction of mobility; moreover, it is easy to apply, has good stability and does not detach over the splinting period. Because of its preshaped holes, the bonding material does not leak all over the tooth surface and the splint remains mechanically well secured on the tooth (MESHARI ET AL. 2016). However, it caused minor esthetic impairment and had the highest material costs (VON ARX ET AL. 2001A).
It might be considered a limitation that this study only compared different variants of the TTS. A lot of other splints like the nylon fishing line have shown good esthetic results as well. Due to the study design, we cannot know if the participants would have chosen the silver matt TTS over the nylon fishing line splint. From the conducted survey we can only say that the silver TTS causes less esthetic impairment than the golden TTS and that more patients prefer the matt surface over the polished one.
In the present study, patients that were well and did not suffer a dental trauma were questioned. Therefore, they were not exposed to such a stressful situation. It remains open, whether trauma patients also see aesthetics as a priority. Furthermore, children and adolescents were deliberately excluded from the study even though they belong to the majority of patients experiencing dental accidents. The authors assumed that aesthetic aspects are more important for adults. That is why the survey focused on them. How the results would differ for children and adolescents would need to be assessed in a further study.
The use of a TTS is of short duration. This raises the question, whether there even is a need for different colored splints, or if a golden one suffices. With the results of the present survey the authors attempted to alleviate the burden of difficult dental situations, such as a trauma, by reducing the aesthetic impact to a minimum. Previous studies demonstrated that the TTS achieves good clinical results. However, from an aesthetic perspective, they are perceived as bothersome (VON ARX ET AL. 2001A; VON ARX ET AL. 2001B; FILIPPI ET AL. 2002; BEN HASSAN ET AL. 2016). Therefore, it is the authors’ belief that dental trauma patients are receptive towards an aesthetic treatment.
The present study investigated eight TTS variants in four different colors with two different surface finishes each. The main objective was to identify any possible preferences regarding optical acceptance of the different splints. The colors were easy to distinguish, but it was difficult to differentiate between the matt and polished surfaces. Nevertheless, the results were statistically significant.
The fact that the difference between the surface finishes was quite small leads to the question of whether the participants should have had the option to check “I don’t see any difference”. This option was not included on the questionnaire in order to get a clear “EITHER/OR” decision. In these cases, the participants were encouraged to have a closer look at the splints and then decide which one they liked best, and not to merely take a quick look and answer “I don’t see any difference”. For a better visual presentation, it might have been helpful to provide a video of the model wearing the different TTS variants. However, it would not have been possible to produce identical videos showing the different splints without computer-animated procedures.
Our study findings suggest that silver matt is by far the most preferred TTS color and surface finish combination. Therefore, it is highly recommended to use silver matt trauma splints, as they can satisfy the needs of almost all patients.
Acknowledgements
The authors thank Dr. Urs Simmen, Statistical Consulting for the statistical analysis and Mrs. Monika Müller for the professional photographs. We are grateful to Mrs. Suzyon Wandrey and Mr. Owen Bürgler-Gärtner for their English language support.
Ethical Approval
This study was approved through the Ethics Committee Nordwest and Central Switzerland EKNZ, in 2016.