[Dental implants in tooth grinders]

Bruxism (tooth grinding and clenching) is generally considered a contraindication for dental implants, although the evidence is usually based on clinical experience only. So far, studies to the possible cause-and-effect relationship between bruxism and implant failure do not yield consistent and specific outcomes. This is partly due to the large variation in the technical and the biological aspects of the investigations. Although there is still no proof that bruxism causes overload of dental implants and their suprastructures, a careful approach is recommended. Practical advices as to minimize the chance of implant failure are given. Besides the recommendation to reduce or eliminate bruxism itself, these advices concern the number and dimensions of the implants, the design of the occlusion and articulation patterns, and the use of a hard nightguard.

The use of a removable appliance to improve oral continence in an elderly dentate patient

Challenges in the treatment of our older dentate patients are arising more frequently, and novel solutions may be required to overcome them. This case report describes the treatment given to an elderly dentate female patient, whose lax peri-oral musculature was preventing a satisfactory oral seal from being achieved. This resulted in constant "drooling" and much social disability in an otherwise fit and gregarious lady. A simple removable appliance was provided to increase support to the tissues at the angles of the mouth. An immediate relief of the salivary leakage was achieved and maintained. Simple solutions may be available to problems which may cause great distress to our patients reducing the quality of their lives. This solution to the problem of peri-oral leakage, of a normal volume of saliva, may be useful for many other patients with similar problems, following loss of peri-oral muscle tone with age.

Restoration of canine guidance on an occlusal splint using amalgam: a clinical report

A primary consequence of sleep bruxism is severe tooth wear. Although an occlusal splint is able to protect teeth, grinding may continue on its surface. This clinical report describes an approach to restore canine guidance on an occlusal splint, with amalgam, for a patient with sleep bruxism. This procedure allowed maintenance of the canine guidance for a period of time longer than 3 months, postponing the fabrication of a new splint.

In vitro wear of various orthotic device materials

STATEMENT OF PROBLEM

Orthotic devices are advocated to decrease occlusal attrition caused by bruxism but tend to wear with time.

PURPOSE

This study investigated the wear rate of various materials used to fabricate orthotic devices.

MATERIAL AND METHODS

Five experimental groups (n=8) were studied: Splint Biocryl autopolymerized (SBA), Splint Biocryl autopolymerized plus additional heat and pressure (SBHP), Forestacryl autopolymerized (FA), Forestacryl autopolymerized plus additional heat and pressure (FHP), and Quick Splint 15-minute (QS), light-polymerized composite. Specimens were mounted to the base of a universal testing machine. A wear device using steatite balls and a load of 9.1 kg was positioned against the specimens, submerged in a 37 degrees C water bath and subjected to 2500 reciprocal cycles. Wear, in micrometers, was calculated as the maximum peak to valley measurement (Ry) using profilometry. Data were subjected to analysis of variance (ANOVA) and Tukey's HSD (alpha=.05).

RESULTS

Mean acrylic wear in micrometers was as follows: FA 6.8 +/-3.0; FHP 7.1 +/- 1.8; SBA 20.4 +/- 5.6; SBHP 23.7 +/- 7.8; and QS 23.8 +/- 6.9. One-way ANOVA detected significant differences between groups (P<.001); the Tukey honestly significant difference test determined that FA and FHP specimens were significantly more resistant to wear than all other specimens (P=.007).

CONCLUSION

Differences in in vitro wear resistance among various orthotic device materials exist. The in vitro wear resistance among other autopolymerizing materials appears to be related to proprietary differences.

The role of mandibular repositioning splint in the orthodontic treatment of patients with TMJ dysfunction

OBJECTIVES

to evaluate the effectiveness of mandibular repositioning splints in the young and adult patients with TMJ dysfunction.

SUBJECTS AND METHODS

23 adult and 14 adolescent patients with TMJ dysfunction selected by Helkimo's index and the criteria of the American Academy of Craniomandibular disorders.

RESULTS

upon anamnestic follow up, almost a total disappearance of the functional pain was reported by all patients, while for the headache, a cyclic onset was present, but with an uncertain etiology. Patients had a complete control of the mandibular movements with some articular sounds. But a modicum of muscular tenderness remained possibly due to the psyche of the patient.

DISCUSSION

the prevalence of dysfunction in the growing patients was an intriguing observation. Not Angle's classification, but the presence of open bite, deep bite, or unilateral cross was the significant etiological factors.

Occlusal interferences and temporomandibular dysfunction

Disagreement exists regarding the relationship between occlusal interferences and temporomandibular joint dysfunction (TMD). This study sought to determine how a balanced occlusion, providing uniform contact in centric relation, would affect signs and symptoms of TMD. A randomly chosen group of 60 patients with occlusal interferences and signs and symptoms of TMD used a mandibular orthotic to balance their occlusions at centric relation (CR). When the occlusions of symptomatic patients were balanced in CR, there was a significant reduction or elimination of TMD complaints, suggesting a relationship between balancing occlusion in CR and optimum management of TMD.

Stabilisation splint therapy for temporomandibular pain dysfunction syndrome

BACKGROUND

Pain dysfunction syndrome (PDS) is the most common temporomandibular disorder (TMD). There are many synonyms for this condition including facial arthromylagia, TMJ dysfunction syndrome, myofacial pain dysfunction syndrome, craniomandibular dysfunction and myofacial pain dysfunction. The aetiology of PDS is multifactorial and many different therapies have been advocated.

OBJECTIVES

To establish the effectiveness of stabilisation splint therapy in reducing symptoms in patients with pain dysfunction syndrome.

SEARCH STRATEGY

Electronic databases (including the Cochrane Oral Health Group's Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); The Cochrane Library Issue 2, 2003; MEDLINE (1966 to June 2001); EMBASE (1966 to June 2001)) were searched. Handsearching of relevant journals was undertaken and reference lists of included studies screened. Experts in the field were contacted to identify unpublished articles. There was no language restriction.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials (RCTs), in which splint therapy was compared concurrently to no treatment, other occlusal appliances, or any other active intervention.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out independently and in duplicate. Validity assessment of the included trials was carried out at the same time as data extraction. Discrepancies were discussed and a third reviewer consulted. The author of the primary study was contacted where necessary. The studies were grouped according to treatment type and duration of follow up.

MAIN RESULTS

Twenty potentially relevant RCTs were identified. Eight trials were excluded leaving 12 RCTs for analysis. Stabilisation splint therapy was compared to: acupuncture, bite plates, biofeedback/stress management, visual feedback, relaxation, jaw exercises, non-occluding appliance and minimal/no treatment. There was no evidence of a statistically significant difference in the effectiveness of stabilisation splint therapy (SS) in reducing symptoms in patients with pain dysfunction syndrome compared with other active treatments. There is weak evidence to suggest that the use of SS for the treatment of PDS may be beneficial for reducing pain severity, at rest and on palpation, when compared to no treatment.

REVIEWER'S CONCLUSIONS

There is insufficient evidence either for or against the use of stabilisation splint therapy for the treatment of temporomandibular pain dysfunction syndrome. This review suggests the need for further, well conducted RCTs that pay attention to method of allocation, outcome assessment, large sample size, and enough duration of follow up. A standardisation of the outcomes of the treatment of PDS should be established in the RCTs.

A Trial of Titration in Oral Appliance Therapy for Obstructive Sleep Apnea Syndrome

This study evaluated the effect of titration in oral appliance therapy for obstructive sleep apnea syndrome (OSAS), and examined problems with this test. However, the method of predicting the appropriate mandible position has not yet been established. In this study, titration was attempted in order to predict appropriate mandible position prior to wearing an oral appliance. Twenty-three male patients diagnosed as OSAS by a physician participated in this study. The mandible was protruded by a titratable splint (TS) until apneic and hypopneic signs had disappeared. Moreover, polisomnography (PSG) was used to monitor brain wave patterns, eye movement, muscle tone, body movement and breathing. Sleep study was performed by a portable sleep monitoring device before and after examination wearing titrated oral appliance (OA), and the effect of therapy was evaluated. The results obtained were as follows. 1. In the Apnea Hypopnea Index (AHI), Apnea Hypopnea density (AH density), lowest SpO2, Oxygen Desaturation Index (ODI), there was a statistically significant improvement. The mean AHI reduced from 13.8 to 4.7 (p<0.001). The mean AH density reduced from 12.0 to 3.5 (p<0.001). The mean lowest SpO2 increased from 78.7 to 84.7 (p<0.0001). The mean ODI reduced from 15.7 to 6.1 (p<0.001). 2.. The average proportion of protrusive distance for movable distance was 71.7%. 3. Only one patient complained of discomfort in the maxillofacial region, however, this discomfort disappeared after adjustment of OA. Therefore, it is suggested that titration for OA is a very useful examination for OSAS therapy.

Application of principles of evidence-based medicine to occlusal treatment for temporomandibular disorders: are there lessons to be learned?

Critical evaluation of treatment methods has become an important part of health care and will certainly have a major influence on decisions about acceptable treatment methods in the future. Evidence-based medicine (EBM) means the systematic, explicit, and judicious implementation of the best evidence in patient care. The most reliable sources of evidence are high-quality systematic reviews and randomized controlled trials (RCTs). A systematic EBM approach could be particularly useful in the treatment of temporomandibular disorders (TMD), where controversial and conflicting ideas about management are common. In this field, concerns about the lack of evidence are often expressed. This article aims to elucidate and discuss the application of EBM to the treatment of TMD, using the most controversial treatments (i.e., occlusal treatments) as an example. By applying the principles of EBM to TMD treatments, we wish to highlight some of the important issues that form the basis for high-quality care in this field. A systematic review of occlusal treatments (occlusal splints and occlusal adjustment) updated to January 2003 revealed 16 RCTs of occlusal splints and 4 of occlusal adjustment. The overall quality of the trials was fairly low. Recently, however, some high-quality RCTs of occlusal splints have been published. The most obvious methodologic shortcomings in published trials included problems in defining the patient population, inadequacies in performing randomization and blinding, problems in defining the therapies or appropriate control treatments, short follow-ups, and problems in monitoring patient compliance. Occlusal splint studies yielded equivocal results. Even in the most studied area, stabilization splints for myofascial face pain, the results do not justify definite conclusions about the efficacy of splint therapy. Their clinical effectiveness to relieve pain also seems modest when compared with pain treatment methods in general. None of the occlusal adjustment studies provided evidence supporting the use of this treatment method. The clinical implications of the findings and future perspectives are discussed.

Treatment effect on signs and symptoms of temporomandibular disorders--comparison between stabilisation splint and a new type of splint (NTI). A pilot study

The aim of the investigation was to compare the effect on signs and symptoms of temporomandibular disorders (TMD) of two different interocclusal appliances. Thirty patients with signs and symptoms of TMD received either a stabilisation splint or a new kind of splint based on the concept of nociceptive trigeminal inhibition (NTI). A clinical examination was performed and subjective symptoms were registered before start of treatment and after 3 and 6 months. All participants were offered to change to the other type of splint at the 3-month follow-up in case of no improvement or impairment of their symptoms. One subject in each group was lost early during the investigation. The mean time for taking impressions, to make inter-occlusal recording and to adjust the stabilisation splints was 17 minutes. The mean time to fit and adjust the NTI splints was 27 minutes. At the 3-month follow-up, 4 patients that had received NTI splints accepted the offer to change to stabilisation splints due to no improvement or impairment of their symptoms. These treatments were judged as failures. No one in the stabilisation splint group utilised the offer to change treatment. At the 6-month follow-up, 7 of the remaining 10 subjects with NTI splints reported some (n = 1) or significant (n = 6) improvement, 2 reported no change and one reported impairment. All 14 who had been treated with a stabilisation splint reported some (n = 2) or significant (n = 12) improvement. For all variables registered, the results were in favour for the stabilisation splint. One subject treated with a NTI splint exhibited an impaired occlusion at the 6-month follow-up.

Short-term clinical outcomes and patient compliance with temporomandibular disorder treatment recommendations

AIMS

To evaluate short-term patient compliance with 5 conservative temporomandibular disorder (TMD) treatments (jaw relaxation, jaw stretching, heat application, cold application, and occlusal splint use) and the association of compliance with changes in pain intensity, pain-related activity interference, and jaw use limitations.

METHODS

Eighty-one TMD patients were given 1 to 5 treatment recommendations as part of usual care in a TMD specialty clinic. Compliance with each recommendation and pain, pain-related activity interference, and jaw use limitation measures were calculated from electronic interviews conducted 3 times daily for 2 weeks.

RESULTS

Median compliance with individual treatment modalities ranged from 7.7% for heat application to 92.7% for jaw relaxation; median overall compliance was 54.8%. Participants with higher initial pain intensity and jaw use limitations were significantly more compliant with their recommended treatment regimen (P < .05). The authors controlled for age, gender, education, and initial jaw use limitations. Overall compliance was associated significantly and positively with 2-week jaw use limitations (P = .03). A trend toward a statistically significant positive association was found between compliance and 2-week pain intensity (P = .09).

CONCLUSION

Compliance varied widely across patients and therapies. Patients with higher initial pain and jaw use limitation levels were more compliant with treatment recommendations. Although compliance was associated with slight increases in pain and jaw use limitations in this preliminary study, further research is needed to evaluate the longer-term effects of compliance with recommended therapies.

An atypical Hallermann-Streiff syndrome. Focus on dental care and differential diagnosis

The Hallermann-Streiff syndrome (HSS) is a rare congenital disorder characterized by dyscephaly, birdlike facies, hypoplastic mandible, congenital cataracts, microphthalmia, hypotrichosis, skin atrophy, proportionate short stature, and dental anomalies. A case of a 29-year-old man with atypical HSS with neither cataracts, hair and skin alterations, nor short stature is reported, with special consideration to oral findings and dental management. Dental extractions, scaling, restorations, and endodontics were performed under local anesthesia. Later, orthodontic rehabilitation with fixed brackets was carried out. Finally, a removable partial denture for the maxillary arch was designed using transparent acrylic, and this also served as a retention splint. Young patients with HSS and other similar syndromes must be involved in personalized oral health prevention programs as early as possible. Despite numerous systemic anomalies, some of these patients may undergo conventional dental procedures under local anesthesia in the dental office.

Does tooth wear status predict ongoing sleep bruxism in 30-year-old Japanese subjects?

PURPOSE

This study investigated whether tooth wear status can predict bruxism level.

MATERIALS AND METHODS

Sixteen Japanese subjects (eight bruxers and eight age- and gender-matched controls; mean age 30 years) participated in this study. From dental casts of these subjects, the tooth wear was scored by Murphy's method. Bruxism level in these subjects was also recorded for 5 consecutive nights in the subject's home environment using a force-based bruxism detecting system. The relationship between the tooth wear score and bruxism data was evaluated statistically.

RESULTS

Correlation analysis between the Murphy's scores of maxillary and mandibular dental arch and bruxism event duration score revealed no significant relationship between tooth wear and current bruxism.

CONCLUSION

Tooth wear status is not predictive of ongoing bruxism level as measured by the force-based bruxism detection system in 30-year-old Japanese subjects.

A-Mode Ultrasound–Based Registration in Computer-Aided Surgery of the Skull

OBJECTIVE

To evaluate the integration and accuracy of A (amplitude)-mode ultrasound-based surface matching for noninvasive registration of the head into a frameless computer-aided surgery system for otorhinology and skull base surgery.

DESIGN

Experimental study and case series.

SETTING

Academic medical center.

PATIENTS

Twelve patients underwent anterior and paranasal skull base surgery with the routine use of a computer-aided surgery system.

INTERVENTIONS

A computer-aided surgery system, based on an optoelectronic localizer, was used to track the skull and the surgical tools, including the A-mode ultrasound probe. The A-mode probe was a 10-MHz immersion transducer. An acoustic lens attached to the transducer focused the ultrasonic beam to a depth of 1 to 10 mm. Accuracy tests were performed for the ultrasound setup. Different surface point distributions were evaluated with respect to matching accuracy on a human cadaver skull specimen equipped with fiducial markers. The matching comparison was based on the fiducial registration error. For the clinical evaluation, the laboratory setup was transferred to the operating room.

MAIN OUTCOME MEASURES

Noninvasive registration of the skull by using A-mode ultrasound in computer-aided surgery (practical and clinical measurements).

RESULTS

The accuracy tests on the human skull specimen revealed that the mean +/- SD fiducial registration error was 1.00 +/- 0.19 mm in the best series for A-mode ultrasound surface matchings and was robust with respect to different sets of surface points. The mean +/- SD root mean square error from the 12 A-mode ultrasound matchings in the patient study was 0.49 +/- 0.20 mm.

CONCLUSION

A-mode ultrasound surface matching can be used as a noninvasive and accurate registration procedure in computer-aided surgery of the head.

Proximal segment positioning in bilateral sagittal split osteotomy: intraoperative controlled positioning by a positioning splint

PURPOSE

Most techniques of proximal segment positioning hinder intraoperative condyle displacement. However, merely maintaining condylar position cannot optimize the preoperative condyle-disc-fossa relationship. This study attempts to optimize condylar position in the osteotomy patient.

PATIENTS AND METHODS

A study group of 23 bimaxillary operated patients had intraoperative joint positioning by positioning splint and plates (9 Angle Class II, 14 Class III). After assessing the habitual and appraising the optimized condyle position on preoperative sonograms and magnetic resonance images, positioning splints were constructed as acrylic occlusal wafers in a semi-individual articulator. Set in occlusion before adaptation of positioning plates, they were intended to move the condyles into the calculated position. Eighteen bimaxillary operated control patients had conventional plate positioning according to the habitual occlusion (9 Angle Class II, 9 Class III). Clinical follow-up, axiography, or sonography was maintained for 24 months. Preoperative lateral cephalograms were scrutinized for horizontal and vertical joint spaces and compared with the immediate postoperative radiography.

RESULTS

Postoperative Class II study group patients had less dorsal and more vertical joint space and Class III patients more dorsal and vertical space compared with the controls. The study group exhibited significantly less postoperative dysfunction compared with the control group (2-way analysis of variance: P <.021, F = 9.2, alpha =.05 significance level), disc dislocation prevalence was lower (P <.07, F = 9.2), postoperative changes in condylar translation were smaller (P <.014, F = 4.9), and 8% skeletal relapses versus 22% in the controls were seen.

CONCLUSIONS

A proximal segment-positioning splint effectively positioned the condyle in the desired direction, but with considerable relapse, significantly reduced postoperative dysfunction, disc dislocations, changes to the condylar translation, and incidence of skeletal relapse at 24-month follow-up.

Oral structures and sleep disorders: a literature review

In recent years, a wealth of studies revealed the many physiological and histological changes the oropharyngeal muscles go through as a result of sleep disorders, in particular, as a result of Obstructive Sleep Apnea (OSA). This article presents a literature review of the most recent findings regarding sleep disorders and their effect on oropharyngeal structures. The article includes classifications and definitions of various sleep disorders; explains the negative implications of sleep disorders in children, as well as in adults; reviews the viable options to treat sleep disorders; suggests steps in which the orofacial myologists could be instrumental in identifying and referring patients with possible sleep disorders; and suggests further studies on the subject conducted by orofacial myologists.

Evaluation and management of TMDs, Part 2

TMDs are only one of a host of different conditions that are part of the broader category of chronic orofacial pain disorders and dysfunctions. Due to multifactorial etiologies, it is imperative to adopt a multidisciplinary approach when evaluating and treating these patients. Table 1 lists the various conditions to consider in the differential diagnosis of orofacial pain disorders.

Temporomandibular disorder or Eagle's syndrome? A clinical report

This clinical report describes the diagnosis and treatment of a patient under emotional stress with orofacial pain, headaches, and the feeling of a foreign body in the throat. An elongated styloid process at the beginning of the oral pharynx was diagnosed. Although these symptoms could be aspects of Eagle's syndrome, deflective occlusal interferences, tender muscles of mastication, and a clicking temporomandibular joint led to an evaluation for temporomandibular disorder related to malocclusion. An occlusal splint was used to confirm the diagnosis and to alleviate symptoms. Occlusal adjustments were subsequently performed. In a 10-year follow-up, the patient had no complaints.