Content uploaded by Melinda Madléna
Author content
All content in this area was uploaded by Melinda Madléna on Feb 22, 2016
Content may be subject to copyright.
A preview of the PDF is not available
Retention and relapse. Review of the literature
Abstract
The retention after orthodontic intervention is just as important part of the therapy as the activ treatment. It is difficult to find statistical data about the frequency and the average degree of the relapse, but some restitution in lower denture is observable in the 70-90% of the cases, in the postretention period. The upper jaw is also frequently touched, but the prevalence and the rate is milder. The authors of this article tried to collect all the factors which are responsible for the orthodontic relapse and to determine the rules should be kept by the planning and the management of the therapy. The age and the maturity of the patients, the result of the orthodontic intervention, the origin and the character of the anomaly, the type of the retainer, the compliance of the patients; all can influence the chance of the relapse. There are some anomalies which more frequently relapse, contrarily some orthodontic irregularities have quite good long-term prognosis. In the first 6 month after the orthodontic treatment any kind of retainer has to be worn nearly 24 hours/day, later 12-14 hours daily wear seems to be satisfactory. The retention period should be twice longer than the activ orthodontic treatment, posteriorly the appliance can be left gradually. Certainly the length of the retention depends on compliance of the patients. Among the retention appliances the fixed retainers are suggested in the lower front area, because the lower incisors are most frequently relapsed.
... [1][2][3][4][5] Orthodontists are more likely to indicate fixed retainers adapted to the lower arch, because of tooth instability in the region, which requires longer stabilization periods. 1,2,6-10 Fixed retainers are more aesthetic, do not depend on patient cooperation, 6,8,11,12 and may be individualized for the diagnosis and treatment performed. 2,13,14 In this context, the 3x3 fixed bar produced with straight wire bonded to the contralateral canines, 1,12,14 the twisted wire bonded to all lower anterior teeth, 1,9,12,15,16,17 and the modified fixed retainer 1,12,14,16 are the mostly used. ...
... It was verified that the mostly used retainer, for both specialties, was the straight wire type (p < 0.05). The retainer that dentists believe accumulate the greatest amount of dental biofilm is the modified one, con- Costa RSM, Vedovello SAS, Furletti-Góes VF, Custodio W, Venezian GC -Orthodontist and periodontist's knowledge, attitudes and aspects of clinical practice, regarding fixed lower orthodontic retainers 11 practice of both type of professionals. Thus, this study chose to include all orthodontists and periodontists, aiming at a more extensive population sample. ...
Objective:
This study aimed to assess the knowledge, attitudes, and aspects of the clinical practice of orthodontists and periodontists, regarding lower fixed orthodontic retainers.
Methods:
The orthodontists (n=502) and periodontists (n=269) who participated in this cross-sectional observational study received, via e-mail, questions related to the type of lower fixed retainer, dental biofilm accumulation, oral hygiene, and potential periodontal changes. The data were subjected to chi-square and Fisher's exact tests, at 5% significance level.
Results:
Both orthodontists (72.3%) and periodontists (58.7%) reported that hygienic retainers accumulate more dental biofilm (p< 0.05), and 64.1% of orthodontists and 58.7% of periodontists considered that modified retainers may lead to periodontal changes (p< 0.05). There was no significant difference between the dental specialties, regarding the type of lower fixed retainer considered the easiest for the patient to perform hygiene (p> 0.05), whereas 48.6% of professionals chose the modified type.
Conclusion:
The modified retainer accumulates a greater amount of dental biofilm and, in the perception of orthodontists and periodontists, it may cause periodontal changes.
... Maintaining the position of corrected teeth is crucial and must be considered from the moment an orthodontic treatment plan is made. 1 Kaan and Madléna stated that retention after orthodontic intervention is as important as active therapy. 2 Even though the teeth have already been in their ideal position, the remodeling and reorganization of the supporting tissues of the teeth have not been finished. 3,4 Gingiva, unlike bone and periodontal membrane, is squeezed and retracted after orthodontic treatment. ...
Objectives The purpose of the present study was to discover how hyperbaric oxygen therapy (HBOT) could reduce orthodontic relapse by altering the expressions of hypoxia-inducible factor (HIF)-1 messenger ribonucleic acid (mRNA), type I collagen (Col I), and matrix metalloproteinase-1 (MMP-1) in the gingival supracrestal fibers in rabbits.
Materials and Methods This study involved 44 male rabbits ( Oryctolagus cuniculus ) randomly divided into the normal group (K0), the orthodontic group without HBOT (K1), and the orthodontic group with HBOT (K2). Following orthodontic separation of the two upper central incisors, a retention phase and relapse assessment were performed. The HBOT was performed for a period of 2, 4, 6, 8, and 10 days after retention. HIF-1α transcription was assessed employing real-time polymerase chain reaction, whereas Col I and MMP-1 proteins were examined using immunohistochemistry. The orthodontic relapse was measured clinically using a digital caliper.
Statistical Analysis We used the one-way analysis of variance followed by Tukey's post hoc for multiple comparisons to measure differences between pairs of means; a p- value of 0.05 was considered statistically significant.
Results HBOT significantly increased the HIF-1α mRNA expression ( p = 0.0140), increased Col I ( p = 0.0043) and MMP-1 ( p = 0.0068) on the tensioned and pressured side of the gingival supracrestal fibers, respectively, and clinically decreased the relapse ( p = 3.75 × 10 ⁻⁴⁰ ).
Conclusion HBOT minimizes orthodontic relapse by influencing HIF-1α expression, collagen synthesis (Col I), and degradation (MMP-1). This result suggests that HBOT has the potential to be used as an adjunctive method in the orthodontic retention phase.
... It could occur due to various reasons, such as the inherent memory of periodontal ligament, changes in skeletal structures surrounding teeth, occlusal forces, labial and lingual pressures, and the normal aging process. 1,2 These factors affect the rate and degree of relapse; hence, wearing an appliance post-treatment is essential in maintaining stable alignment of the dentition. [3][4][5][6] Clinicians may offer fixed or removable options, and among the most prescribed are the removable Hawley retainers (HR) and removable Vacuum-formed retainers (VFR). ...
... Several factors have been linked with relapse such as, the retention protocol, patient compliance, patient's age, and the final occlusal result (39). Moreover, it has been suggested to be related to the elastic fibers of the periodontal ligament (in relapse of rotated teeth), pressure from the soft tissues, continuing residual growth, and occlusal contacts (40). ...
Aim: To evaluate the stability of orthodontic treatment outcome 2 years after orthodontic treatment, and to investigate the influence of different pre- and posttreatment prognostic factors on stability.
Materials and Methods: Consecutive patients treated with full fixed appliances and retained with fixed retainers were retrospectively selected and assessed for eligibility. Information regarding age, gender, and retention protocol was extracted from the patient's records. Digital models were analyzed at the start of treatment (T0), end of treatment (T1) and 2 years posttreatment (T2). Peer Assessment Rating (PAR) index, Little's Irregularity Index (LII), arch width, arch length, overjet and overbite were assessed. In addition, retainer protocols at T1 and retainer changes at T2 were recorded according to patients’ records. Finally, the presence of unexpected posttreatment changes was recorded. Multiple regression models were conducted to model the relationship of all outcomes with several prognostics simultaneously.
Results: The final sample comprised the records of 287 subjects. The mean weighted PAR score was 29.5 (SD 8.6) at T0, 1.8 (SD 2.9) at T1 and 3.2 (SD 3.6) at T2. Ninety-five percent the subjects had a perfect LII at T1, while 86% of the subjects still had a perfect LII at T2. Differences in LII between T1-T2 showed unstable results in 12 subjects, whereas PAR index showed absolute stability in 147 subjects, relative stability in 119 subjects, and instability in 21 subjects. An increase of 1 mm of LII at T1 was shown to correlate with a change of 68 in odds of being in a worse LII category at T2. The PAR score at T1, as well as the PAR score and overjet at T0, were other significant factors for the PAR improvement T0-T2. Five retainers (1.7%) showed unexpected posttreatment changes at T2. Fixed retainers were exposed to changes over the 2-year follow-up period; some retainers were removed, while other retainers were shortened.
Conclusion: The treatment outcome and the 2-year stability were very good. Several prognostic factors for stability could be identified, including LII and PAR score at T1, suggesting that good quality of treatment outcome might ensure postretention stability.
... Also, keeping the tooth in its position after treatment seems challenging in orthodontic field; hence multiple points of views and schools had displayed their solutions for that. [1][2][3][4] During all of orthodontic treatment, the widths of both mandible and maxilla increase during the aligning phase with or without extractions. The higher changes took place in the area of premolars, then in the area of canines and, finally, in the area of molars, due to that, proper determining the arch form of the patient considered to be an essential parameter in creating a stable, functional and esthetic orthodontic treatment result, since failure to keep the arch form might raise the probability of relapse. ...
The demands for orthodontic treatment are in continuous increasing, hence producing an ideal treatment plan need to cover all stages of the treatment carefully, especially the retention and stabilization stage. As, any changing in the arch width through changing the inter-molar width will lead to impair the stabilization of the arch and will lead to relapse. Due to that, the present study performed to evaluate the inter-molar width of the mandible using three different commercial orthodontic wires. Thirty patients had been allocated in this study, using a cone beam computed tomography to create an assessment for the inter-molar width. It concluded that there is an increase in the inter-molar width between pre-treatment and after finishing of aligning stage, also there is a highly significant increase in post-aligning stage between the three groups.
... 1 A previous study reported relapse postorthodontic treatment rates of approximately 70 to 90%. 2 Relapse recognized as a major challenging orthodontic clinical issue. A more comprehensive understanding of the relapse process is needed to determine ways to alleviate relapse or reinforce retention. ...
Objective The study aimed to determine the effect of carbonate apatite (CHA) hydrogel-aPRF on osteoblastogenesis during relapse in rabbits.
Materials and Methods Forty-five rabbits were divided into three groups (n = 15): the control, CHA, and CHA-autologous platelet-rich fibrin (aPRF) groups. An open-coil spring was compressed between brackets to distalize the lower incisors of the rabbits by delivering a force of 50 cN for 1 week. The new position of the teeth was retained for 14 days, and CHA hydrogel-aPRF was injected every 7 days. The appliances were then debonded to allow relapse. On days 0, 3, 7, 14, and 21 after debonding, transforming growth factor (TGF)-β1 and bone morphogenetic protein (BMP)-2 expression was examined using immunohistochemistry staining and Runx-2 levels were analyzed by enzyme-linked immunosorbent assay. The data collected were analyzed using analysis of variance and a post hoc Tukey’s test (p < 0.05).
Results Histomorphometric analysis revealed that TGF-β1 expression in the CHA-aPRF group is statistically higher than that in other groups on days 0, 3, and 7 after debonding (p < 0.05). BMP-2 expression in the CHA-aPRF group was also statistically higher than that in the other groups on days 3, 14, and 21 after debonding (p < 0.05). ELISA showed that Runx-2 levels are slightly higher in the CHA-aPRF group than in the other groups (p > 0.05).
Conclusion Although injection of CHA-aPRF aids in osteoblastogenesis associated with enhancing TGF-β1 and BMP-2 expressions, it does not significantly upregulate Runx-2 levels.
Relapse during passive orthodontic treatment is a major issue, with 70–90% frequency. This study examines whether blood cockle shells may be used to extract carbonated hydroxyapatite (CHA)-chitosan (CS). This study also aims to analyze the effect of CHA-CS on orthodontic relapse in rats. This study utilized 18 male Wistar rats which were randomly divided into two groups: CHA-CS and the control group (CG). The rats were subjected to a 35 cN orthodontic force for a duration of 7 days, after which the rats were conditioned to be passive. During this phase, the CHA-CS group received daily administration of CHA-CS hydrogel derived from the blood cockle shell. Subsequently, the appliances were detached to facilitate relapse. The distance between the mesial tips was measured using a digital caliper at three consecutive time points: 1, 5, and 7 days after debonding. The number of osteoblasts, osteoclasts, and fibroblasts was examined using hematoxylin–eosin staining. The data were subjected to statistical analysis using a t-test. The relapse distance of the CHA-CS group was lower than that of the control groups on day 7. Histological examinations using hematoxylin–eosin (HE) staining showed a significant increase in osteoblasts, a decrease in osteoclasts, and an increase in fibroblasts during orthodontic relapse movement (p < 0.05). This study found that blood cockle shell-derived CHA-CS may reduce orthodontic relapse by increasing osteoblasts and fibroblasts and by reducing the osteoclast number in rats.
The biggest challenge nowadays is finding and keeping quality employees in order to meet organizational needs and business demands. According to this perspective, talent emerges as the keystone of organizational strategy. The authors made the modest effort to identify the factors that significantly contribute in luring prospective and resourceful employees more to their employer. Sample size for this study was 440 employees currently working in IT sector in Kolkata. The authors found this research study to be a noble contribution since talent retention practice will serve as a base for employer branding and will play the influencing role for the IT companies to reach the pinnacle of success. In addition to providing a competitive edge, these factors would also allow for the establishing the employer branding concept, which would later pay off handsomely.
The aim of this systematic review is to analyze the properties of the different types of orthodontic retainers,
identify their differences and define which type of device is most effective and less harmful to periodontal health.
Methods: A literature search was carried out by a reviewer by consulting PubMed, Lilacs, Embase, Medline full
text, Scopus, Web of Science, Cochrane library, and Science Direct electronic databases for biomedical and health
literature as well as the grey literature and setting up the search from December 2010 without any restriction
about articles languages.
Results: The results showed that patients who wear retainers for a long period have significant differences in
clinical parameters compared to patients without retainers. The type of retainer chosen also significantly influences
the overall periodontal health of patients. Fixed retainers, both glass-fibre reinforced and steel wire
retainers, proved to be the retainer type with the highest plaque and calculus accumulation values compared to
removable retainers. In addition, among fixed retainers, glass-fibre reinforced retainers proved to be those that
mostly promote the plaque and calculus accumulation in the application site.
Conclusion: Fixed retainers are the best devices to maintain the alignment of mandibular anterior teeth in the long
term. Among these devices, stainless steel lingual retainers, plain or braided, should remain the first choice.
Although they are also susceptible to periodontal complications, their effect on periodontal health can be
considered statistically insignificant if compared to glass-fibre reinforced retainers which, showing worse periodontal
complications, should not be used.
Background
An adhesive with both proper mechanical and antimicrobial properties seems to be beneficial. We aimed to investigate the effect of zinc oxide (ZnO) and titanium dioxide (TiO2) nanoparticles (NPs) on bond strength and microleakage of two different fixed retainer adhesives.
Methods
In this in vitro experimental study, 168 extracted human incisors were randomly divided into six groups of 28 (eight double-tooth specimens for the bond strength test and 12 specimens for the microleakage test). In three groups: Transbond XT (3M Unitek, Monrovia, CA) without NPs, with 1% ZnO NPs and with 1% TiO2 NPs were applied. The other three groups included Ortho Connect Flow (GC orthodontics, Tokyo, Japan) composite with the same order to bond a 0.175-inch multistrand wire to the lingual surfaces of the teeth. The bond strength was measured using the Universal Testing Machine, and the adhesive remnant index was reported using a stereomicroscope (Nikon, SMZ800, Tokyo, Japan). The dye-penetration method was used to determine the microleakage.
Results
For bond strength, there was no significant difference among groups. For microleakage, there was no significant difference between GC and Transbond XT groups. However, in subgroups of Transbond XT, the addition of TiO2 NPs increased the microleakage significantly in comparison with ZnO and control groups (P = 0.011). There was no significant statistical difference between the groups in terms of residual adhesives (P = 0.166).
Conclusions
Through the incorporation of 1% TiO2 and ZnO NPs into the fixed retainer adhesive, the bond strength was maintained within the clinically acceptable range. The addition of TiO2 NPs to Transbond XT significantly increased the percentage of microleakage.
Oral health is basically important for the well-being of people. Thus, it is strongly suggested to organize epidemiological surveys in order to gain representative data on oral condition of the given population. The purpose of the cross-sectional study was to determine the results on tooth loss and caries prevalence of Hungarian adults in different age groups.
Altogether 4606 persons (2923 women, 1683 men) participated in the study who were classified into different age groups: 19 [less than or equal to], 20-24, 35-44, 45-64, 65-74, [greater than or equal to]75 year olds. Probands were selected randomly from the population attending the compulsory lung screening examinations. The participants were examined by calibrated dentists, according to the WHO (1997) criteria. In order to produce representative data, the chosen localities for these examinations covered the capital, the largest towns, the villages, and case weights were used for the statistical evaluation.
The mean values of DMF-T were found between 11.79+/-5.68 and 21.90+/-7.61 These values were significantly higher in women compared to men (p < 0.05). In all age groups the values of M were the highest. Except for the women in the groups of 35-44 and 45-64 year olds, these values showed an increasing tendency both in women and men by age (from 5.50+/-6.49, and 4.70+/-4.08 to 21.52+/-9.07 and 18.41+/-8.89 respectively). The values of D components reached the highest values in 45-64 year olds (4.54+/-2.12 and 4.22+/-2.81, by gender, respectively), then in the older age groups there was a high reduction in these values (in 65-74 year olds: 2.72+/-1.88 and 1.36+/-2.48; in 75 or more than 75 year olds: 1.05+/-1.41 and 1.03+/-1.76 by gender, respectively). The ratio of D and F values was the highest in the age group of 65-74 year olds (2.12), the lowest ratio could be calculated in 20-34 year olds (0.65).Data showed some decrease in caries experience in 35-44 years of age between 2000 and 2004. The prevalence of persons with 21 or more teeth had been increased from 65.6% to 73.1%. This positive tendency has not been occured in prevalence of edentulousness in this age group: the prevalence of edentulous persons changed from 1.4 to 1.9%. In 65-74 year olds the level of edentulousness became lower, from 25.9 to 14.8% and the prevalence of persons with 21 or more teeth is higher (22.6%) than it was in 2000 (13.0%).
Present data from Hungary show some slight decrease in caries experience between 35-44 years of age, although this positive tendency has not been occured in prevalence of edentulousness in this age group. A positive tendency could be experienced in the group of 65-74 year olds in edentulousness and in number of teeth, but further efforts are needed to reach a better situation.
This article discusses the aetiology, signs and symptoms, diagnosis, psychological factors and management of temporomandibular disorders (TMD). It highlights the difficulty of evidence-based practice with respect to TMD.
Correction of the occlusion in Angle Class-II/2 patients is often more complicated and tedious than in Class-II/1 cases. Reasons given are the more comprehensive remodeling and functional adaptation processes of the temporomandibular joints (TMJ) since the articular tuberculum is more strongly developed in deep overbite, and a deep bite leading to a locked occlusion is dominant due to the steeper condylar path. Both characteristics are, however, considered to be the consequence of pronounced incisor retrusion.
The present study covered 28 untreated Class-II/2 patients aged 8 to 12 years in whom functional TMJ adaptation to the retroclined maxillary incisors was studied with the help of electronic, 3D axiographic registrations of mandibular movements. Comparison with eugnathic age peers revealed increased mobility in mandibular protrusion and a somewhat steeper condylar path, although the latter was less pronounced than in adult patients.
The results corroborate the concept of functional TMJ adaptation to incisor inclination and speak for early uprighting of maxillary incisors.
Traditionally, four groups of factors have been identified in the etiology of temporomandibular disorder (TMD): anatomical variation in the masticatory system; psychosocial characteristics; pain in other body regions; and demographics. Orthodontic treatment has been variously cited both as a protective and harmful factor in TMD etiology. Recently, a search has begun for a genetic influence on TMD etiology. Genetic markers can be of additional value in identifying gene-environment interactions, that is, isolating population sub-groups, defined by genotype in which environmental influences play a relatively greater or lesser etiological role. This paper reviews concepts and study design requirements for epidemiological investigations into TMD etiology. Findings are presented from a prospective cohort study of 186 females that illustrate an example of gene-environment interaction in TMD onset. Among people with a variant of the gene encoding catechol-O-methyl-transferase, an enzyme associated with pain responsiveness, risk of developing TMD was significantly greater for subjects who reported a history of orthodontic treatment compared with subjects who did not (P=0.04). While further studies are needed to investigate TMD etiology, this genetic variant potentially could help to identify patients whose risk of developing TMD is heightened following orthodontic treatment, hence serving as a risk marker useful in planning orthodontic care.
Overbite and overjet were studied as continuous variables to examine for any relationship to diagnostic groups of temporomandibular disorders (TMD) compared with symptom-free controls. This avoided the bias of arbitrary definitions of normal and abnormal for these occlusal variables and also avoided the masking effect of studying symptoms rather than diagnostic entities. Incisal overbite in primary osteoarthrosis (OA) was shifted toward the minimal and open bite ranges as compared with the controls (p less than 0.02). Open bite occurred in only the two OA classes studied and in a few cases with myalgia only but was absent in the symptom-free controls. Overbite in myalgia was slightly skewed to the lower range. Deep bite was not more common in the myalgia, disk displacement (with or without reduction), or the OA groups. Increased overjet characterized OA groups, especially when there was a history of derangement (p less than 0.004), but did not characterize the other diagnostic groups. Except for open bite, overbite and overjet characteristics as isolated variables did not distinguish TMD patient groups. It is hypothesized that open bite in OA can be the result of joint changes rather than a predisposing occlusal cause.
An association was sought between certain morphologic characteristics of malocclusion—Angle classification, over-bite, over-jet, open-bite, cross-bite and crowding—and the presence or absence of three cardinal symptoms of mandibular dysfunction—joint sounds, joint sensitivity to palpation and muscle sensitivity—in a sample of 369 1 school children. In addition, two additional independent variables, ‘occlusa, wear’ and ‘previous orthodontic treatment’ were introduced into the statistical analysis.
Occlusal wear and abnormal overbite were the only factors found to increase significantly the presence of dysfunction symptoms.
In order to investigate the correlations between genioglossus, masseter, and orbicularis oris muscle activity and craniofacial morphology, an electromyographic and cephalometric analysis was undertaken on a series of twenty-four human subjects. The activity from the muscles was recorded during voluntary opening movements of the mandible monitored by an electronic transducer. A computer-based method was devised to calculate the threshold incisor-separation position corresponding to a 20 percent increase in base line muscle activity for each of the muscles. In addition, twenty-seven anatmoic points were digitized from lateral head films, and a computer-based cephalometric analysis was completed for each subject. A number of significant correlations were found between the threshold muscle values and the thirty-one linear and angular morphologic variables. Low threshold values for the genioglossus muscle were correlated with negative overbites, undererupted maxillary and mandibular incisors, and low total face heights. Low threshold values for the masseter muscle were also associated with low overbite measurements. In contrast, orbicularis oris muscle thresholds did not appear to be correlated with any of the craniofacial variables measured. This interdependence of tongue and jaw muscle activity and facial morphology suggests a contribution of the musculature to the development and/or maintenance of the dentition.
The Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) guidelines, originally developed in the United States, were translated and used to classify TMD patients on physical diagnosis (Axis I) and pain-related disability and psychologic status (Axis II) in a TMD specialty clinic in Sweden. The objectives of the study were to determine if such a translation process resulted in a clinically useful diagnostic research measure and to report initial findings when the RDC/TMD was used in cross-cultural comparisons. Findings gathered using the Swedish version of the RDC/TMD were compared with findings from a major US TMD specialty clinic that provided much of the clinical data used to formulate the original RDC/TMD. One hundred consecutive patients were enrolled in the study. Five patients with rheumatoid arthritis and 13 children or adolescents were excluded. The remaining 82 patients participating in the study comprised 64 women and 18 men. Group I (muscle) disorder was found in 76% of the patients; Group II (disc displacement) disorder was found in 32% and 39% of the patients in the right and left joints, respectively; Group III (arthralgia, arthritis, arthrosis) disorder was found in 25% and 32% of the patients in the right and left joints, respectively. Axis II assessment of psychologic status showed that 18% of patients yielded severe depression scores and 28% yielded high nonspecific physical symptom scores. Psychosocial dysfunction was observed in 13% of patients based on graded chronic pain scores. These initial results suggest that the RDC guidelines are valuable in helping to classify TMD patients and allowing multicenter and cross-cultural comparison of clinical findings.
This article begins by reviewing the history of etiologic thinking in the field of temporomandibular disorders (TMD). I conclude from this review that not only are the old mechanistic etiologic concepts incorrect, but also that 2 of the most popular current concepts (biopsychosocial and multifactorial) are seriously flawed. Therefore, what we really have at the individual TMD patient level is nearly always an idiopathic situation--we simply do not know enough, or cannot measure enough, or cannot precisely determine why each patient has a TMD. In addition, we do not understand the host resistance factors that ultimately determine why one person gets sick while another does not. The issue of "why" (etiology) must be differentiated from the issue of "how" (pathophysiology), both semantically and intellectually, to discuss all of this properly. However, our current inability to precisely identify etiologies in TMD patients does not prevent us from providing sensible (and often successful) treatment for most of these patients. Many health conditions currently are treated by physicians and dentists with either incomplete or flawed understanding of their etiology, but the availability of empirical data about treatment outcomes permits some level of appropriate care to be given. Fortunately, a large number of comparative studies have been done in the field of TMD therapy, providing us with a basis for selecting initial therapies as well as for dealing with treatment failures. Even in the absence of a perfect understanding of etiology, we still can provide good conservative care, and we should avoid aggressive and irreversible treatments, especially when they are based on flawed concepts of etiology. The article concludes by discussing current basic science research activities in the field of TMD and orofacial pain. I propose that these ongoing studies of the molecular and cellular mechanisms of joint disease, muscle pain, and chronic pain are the most likely avenues to future progress in this field, as specific countermeasures are developed to become the basis for more precisely targeted therapies.