Presentation of the CSS System (Compliance Science System)

as a way to evaluate the use of headgear anchorage appliances

Carlos Rodrigues Júnior 1

Karina S. Mundstock 2

Carlos A. Mundstock 3

 

SUMMARY

The aim of this paper is to present an evaluation system of the use of headgear appliances. This system is called Compliance Science System (CSS) and it consists of a headgear neckstrap with an electronic module timer, a reader of this module connected to the computer, and software that reads the information gathered by the module. The CSS system has the purpose of quantifying headgear use timing, determining patient cooperation during the periods of daily use. Two (2) clinical cases with skeletal malocclusion of Class II and severe overjet, treated with the use of cervical-pull headgear, Kloehn type, were presented to illustrate the use of the CSS System.

 

 

TERMS

Headgear, Cooperative behavior, Angle Class II malocclusion, Orthodontics.

 

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1 Orthodontics Specialist at FO-UFRGS.

2 Master at the Birmingham-USA University of Alabama (UAB), Professor at the UFRGS Specialization Course in Orthodontics.

3 Orthodontics Master and Professor at FO-UFRGS.

 

 

Introduction

Headgear anchorage appliances have been used in Orthodontics since last century. Several technical modifications have been made, but the patient cooperation factor has remained the same, mainly in relation to the number of hours recommended to appliance use. Patients’ lack of cooperation, a factor present in most treatments, may influence the final result of the orthodontic treatment as well as its period of time.

There is substantial technical efficiency in the headgear anchorage appliances. A very important headgear appliance use is the one related to growth modification. The problem arises when patients do not cooperate as to the prearranged number of hours the headgear appliance should be worn, and not enough psychological argumentation is obtained to convince and motivate them to tolerate and cooperate in the use of the appliance. Besides, it is difficult to assess patient cooperation in the use of headgear appliances. Among several ways to determine the use of headgear anchorage appliances, there are such subjective methods as: dental mobility, extra-oral tubes cleanliness, neckstrap cleanliness, easy appliance placement, patients’ questioning about daily use number of hours, spaces between teeth, position of the molars compared to pre-treatment models and maintenance evaluation or anchorage loss.

Today, besides the subjective methods, it is possible to make use of objective methods that allow you to measure the cooperation level obtained during the use of the headgear anchorage appliances.

Northcutt5 reported his experiment with a device that was composed of a miniature electronic clock and a memory circuit. According to the doctor, patients increased their number of hours when they learned about the monitoring: from 35-50 hours a week they moved up to over 100 hours a week.

Cureton et alii1 concluded that monitoring patients without their knowing, during the use of headgear appliances, will enable orthodontists to get feedback about their motivational techniques. The same author did another study comparing the subjective evaluation made by expert orthodontists, assistants and interns with an objective evaluation made by an electronic clock (headgear timer); the results showed that patients wore the headgear appliances half the recommended time.2

In a third study, Cureton et alii2 used headgear timers to monitor 28 patients: 14 used schedules to control the daily number of hours and 14 did not use this control. The final result showed that the ones who used schedules for daily control were more committed to appliance use.

In 1997, Güray and Orhan4 did a study, using a timer, in which the authors highlighted the importance of knowing about the duration of headgear appliance use. It was concluded that as patients learned they were being measured, their number of hours went up to over 10 to 14 hours a day, that is, 26% more than when they did not know about the monitoring.

In 1974, Northcutt5 used an electronic monitor manufactured by Aledyne Corporation (Aledyne Timers); Cureton et alii1,2,3 made use of a homemade monitor: a Seiko Lorus Quartz clock mounted with Unitek’s traction straps (3M).

After technological advances in 1998, Ortho Kinetics Corporation launched the Compliance Science System (CSS), whose aim is to objectively inform both orthodontists and patients about the number of hours of headgear anchorage appliances use.6

In order to test CSS system’s efficiency, a research is being developed at the Orthodontics Specialization Course of the Federal University of Rio Grande do Sul (UFRGS). It makes use of a certain number of patients with Angle Class II malocclusion who need the use of a headgear appliance, including the cases described in this paper. The objective of this research project is to assess patient cooperation levels in relation to the use of headgear anchorage appliances and its efficiency, as well as to determine the ideal protocol for daily use number of hours according to the orthodontic treatment objective.

CSS system components

Ortho Kinetics system and structure are simple. They comprise two main elements:

  1. a reader and a program, both used on a PC;

  2. a module (Affirm module) for each cervical or occipital straps (Figure 1).

The reader is a device that reads the module (Figure 1) as well as registers and stores data which will be read through graphs and figures in the program. The reader is attached to the computer serial port (the same access to the mouse) and the communication between the reader and the module is done via infrared light.

Figure 1 – Module placed on the strap and on the reader.

The configuration requirements for the program installation and its utilization are simple and minimum. 486, 8MB RAM computer processors with 10MB hard disk storage may be used. Access to an exclusive CSS serial port is necessary on a desktop computer; laptops and notebooks already display such additional serial port.

The module contains three main components:

  1. a microprocessor which tracks appliance use in a systematic way;

  2. a quartz crystal which measures time precisely;

  3. an optical button which reads the headgear appliance status.

When the strap is pulled, the optical button is turned on, and when the strap is idle, the button is off. The microprocessor checks the optical button every minute to see if the unit is in session (on) or out of session (off). Lithium batteries supply the module with power. Each battery’s life span is 2-3 years from module manufacture date.

The program must log information data of patients who wear the headgear appliance with the module. In every visit, the program automatically reads the modules put in the reader, updates data and creates graphs that report patients’ behavior during the period analyzed. Besides daily use number of hours, the program evaluates in which period of the day patients are concentrating their effort and cooperation. For this to be done, the records have to be accomplished in sessions between 0 – 3 hours, 3 – 6 hours, 6 – 9 hours, 9 – 12 hours, 12 – 15 hours, 15 – 18 hours, 18 – 21 hours. In this way it is possible to evaluate patients either per session or per average use sessions as well as to assess the total number of hours, duration and frequency of each session. Through this system it is possible to evaluate if 8 1-hour sessions will result in the same tooth movement as an 8-hour session.

CSS system principles and philosophy

In the evaluation of headgear appliances it is more important to understand the frequency and duration of appliance sessions than to know the force level applied during a certain time. A change in the number of sessions or an increase in session duration will probably produce better results in the treatment final result.

The importance of knowing the duration of each use session can be exemplified. For example, if a patient puts on the appliance for the first time at 6 p.m. and takes it off at midnight, there is a session of 6 hours. On the second day, the appliance starts to be worn at 7 p.m. and is removed at 8 am of the following day, resulting in a 13-hour session. On the third day, the patient puts on the appliance at 3 p.m. and takes it off at 5 p.m., then resumes use at 8 p.m. until 8 am of the following morning, resulting in a session of 2 hours and another one of 12 hours. In short, we will have 3 days of use with 4 sessions; two sessions of short duration and two sessions of long duration. This means that the patient is trying to wear the appliance with dedication, and the system is displaying his level of cooperation.

It can be concluded that by knowing the duration of every session, two immediate benefits will be obtained:

  1. The level of cooperation can be controlled, and patients will probably increase the number of hours in their use when they learn, by means of figures, about their performance and that they are being evaluated.

  2. Orthodontists will be able to know objectively which effort and cooperation their patients are showing in relation to the appliance.

Clinical experiments

CASE 1

Patient C.M., 9 years and 2 months old, female, mixed dentition phase, with Angle Class II malocclusion, first division, overjet of 8 mm and overbite of 4 mm (Figure 2). The patient’s cephalometric measures are: SNA 87,2o, SNB 80,3o, ANB 6,9o, SND 75o, 1/-NA 5 mm, 1/-NA 27,4o, /1.NB 5,8 mm, /1.NB 33,1o, SN.GoGn 28,3o (Figure 3).

Figure 2 (a and b) – plaster models, right and left sides respectively, before treatment.

Figure 3 - Patient C.M.'s pre-treatment cephalometric tracing.

 

C.M.’s treatment plan included a superior and inferior complete fixed appliance as well as Angle Class II malocclusion and overjet correction by means of an extra-oral appliance with cervical traction. It was suggested that the patient wear the headgear appliance 14 hours a day. The patient was cooperative, with evident clinical distalization of the first superior permanent molars in a period of 5 months (Figure 4). According to the CSS system reading sensor, the patient wore the headgear appliance on a daily average of 10,6 hours/day instead of the 14 hours/day recommended initially (Figure 5). She wore the appliance mainly during the night (see Figure 6 graph). It was observed that the patient concentrated her biggest effort in the sessions between 9 – 12 hours and 12 – 15 hours, probably at sleeping time. Clinically, in a subjective evaluation, the patient was inquired about the period and frequency of headgear use, and her replies coincided with the information supplied by the CSS system. Besides, clinical evidences of extra-oral traction were verified, like: mobility of the first superior permanent molars (16 and 26) and diastemas between pre-molar teeth.

 

Figure 4 (a and b) – Intra-oral photographs, right and left sides respectively, after 5 months of extra-oral appliance use with the CSS system.

Figure 5 – Demonstrative graph of C.M.’s behavior, with the number of hours of extra-oral appliance use in 5 months’ treatment.

 

Figure 6 – Demonstrative graph of the part of the day the patient mostly concentrated the use of the extra-oral appliance.

CASE 2

Patient FRP, female, initial age 8 years and 4 months, mixed dentition phase, with Angle Class II malocclusion, first division, overjet of 9 mm and overbite of 2 mm (Figure 7). The patient’s cephalometric measures are: SNA 85,7o, SNB 76,3o, ANB 9,37o, SND 73,3o, 1/-NA 7,3mm, 1/-NA 25,5o, /1-NB 5,73mm, /1-NB 26,3o, SN-GoGn 37,9o (Figure 8).

Figure 7 (a and b) – Pre-treatment intra-oral photographs, right and left sides respectively.

Figure 8 - FRP’s pre-treatment cephalometric tracing.

 

The patient’s treatment plan included a superior and inferior fixed orthodontic appliance and use of an extra-oral cervical pull appliance for correction of Class II malocclusion and overjet. It was suggested that the patient wear the headgear appliance 18 hours a day. The patient demonstrated clinical signs of cooperation (Figure 9). This clinically obtained information was confirmed via CSS sensor reading. The CSS system informed as an average daily use of the extra-oral appliance a total of 14,3 hours (Figure 10). The biggest effort in use was between 9 – 12 hours, and there was also a complement between 0 –3 hours (Figure 11). Predominant use was probably during the night, at sleeping time, also having some extra-oral use during the day.

 

 

 

Figure 9 – Intra-oral photographs after 5 months’ treatment, right and left sides respectively.

Figure 10 – Demonstrative graph of FRP’s behavior, including the number of hours of extra-oral appliance use in a 5-month treatment.

Figure 11 – Demonstrative graph of the part of the day the patient mostly concentrated the use of the extra-oral appliance.

 

Analyzing the clinical results obtained in a short period of time it may be questioned if the number of hours of daily use recommended initially was not excessive in case of a cooperative patient.

 

Conclusions

The data supplied by literature along with the information obtained through the use of the CSS system until the present date suggests that monitoring extra-oral appliances use may be an advantage to orthodontic treatment success, and it may be used as a tool to patient cooperation level improvement. It was also verified that some patients improved their performance after learning they were being measured or controlled. 12 to 18 hours/day are usually recommended in the extra-oral traction use protocols, which goes against most readings and the results obtained at the UFGRS post-graduation clinic in Orthodontics with the use of the CSS system.

MAIL ADDRESS

CARLOS RODRIGUES JÚNIOR

Faculdade de Odontologia – UFRGS – Ortodontia

Rua Ramiro Barcelos, 2492

Porto Alegre – RS

E-mail: junior@conex.com.br

 

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