Positional changes of the lips concomitant to incisor retraction: an important issue in orthodontics.

Lip response to incisor retraction following extraction therapy is continuously investigated. The following is a summary of available evidence in this regard. The reaction of the lips to incisor retraction cannot be predicted with certainty. This is due to many variables such as gender, growth, morphology, and function. Also, for some patients, it is difficult to completely relax their lips during cephalogram taking. All these variables interact in studies on this topic.

Coating failure of commercial orthodontic magnets and DNA fragmentation of oral mucosa cells.

OBJECTIVE: To investigate possible adverse effects of orthodontic magnets on the oral mucosa. METHODS: Twenty orthodontic patients, between 14 and 20 years of age, were used. All patients consented to participate in the trial, which ran for six months. Following extraction of the first premolars, samarium-cobalt (SmCo5) orthodontic magnets were used to move the upper right canines into the extraction spaces. The contralateral canines were retracted with elastomeric chain. The orthodontic appliance consisted of direct-bonded standard edgewise fibreglass brackets and molar tubes, and teflon-coated preformed archwires. At regular scheduled visits the following were recorded: the condition of the protective magnet coating; weight loss by the magnets; levels of nickel, iron and chromium ions in unstimulated saliva; viability of recovered oral mucosa cells with trypan blue. DNA fragmentation of the oral mucosa cells was analysed at the start of the trial, after one week, one month, three months and six months with the single cell gel electrophoresis assay (Comet assay). The elemental compositions of five magnets were assessed with energy dispersive X-ray microanalysis. RESULTS: By the third month the magnets had lost their protective resin coats. At six months the magnets had lost 3 per cent of their initial weights. Significant weight loss and raised saliva levels of nickel, iron and chromium ions occurred from the first week. The number of oral mucosa cells with DNA fragmentation increased steadily on both sides of the mouth from the first week. More DNA fragmented cells occurred on the Magnet side than on the Non-magnet side. The trial was discontinued when half of the subjects showed DNA damaged mucosal cells. CONCLUSIONS: Because the protective coating failed after a few weeks, orthodontic magnets are unsuitable for long-term intra-oral use. It is uncertain if the greater cell damage on the Magnet side was due to the corrosion products, proximity to the static magnetic field or both factors.

Medicolegal perspective: interpretation of pretreatment orthodontic radiographs.

AIM: To detect the prevalence of anatomic anomalies and pathologic findings that could be screened from pretreatment orthodontic radiographs. METHODS: A thorough screening was conducted of the pretreatment orthodontic radiographs of a sample of 1,354 patients, collected by the author during the last 15 years from 4 locations, 3 in the Kingdom of Saudi Arabia and 1 in Egypt. RESULTS: A total of 154 significant anomalies and pathologic findings were recorded among the total sample group of 1,354 orthodontic patients (11.4%). Among these, 22 could have a serious effect on the general health of the patient. The findings included fractured odontoid process of the axis vertebra, os odontoideum, spondylolisthesis, fractured surgical needle in the oropharynx, fractured transpalatal archwire swallowed and stuck in patient's throat, unrecognized carotid artery stenosis, cystic lesions, and calcified stylohyoid ligaments. CONCLUSION: Medicolegal litigation is a main priority for the clinician, requiring cautiousness through screening of the pretreatment orthodontic radiographs beyond orthodontic purposes to exclude patients with significant anomalies and pathological findings. If not done from the medicolegal prospective, such screening should at least take place from an ethical perspective. The orthodontic clinician needs to know when to consult other medical specialties.

Sella turcica bridges in orthodontic and orthognathic surgery patients. A retrospective cephalometric study.

OBJECTIVE: To investigate the prevalence of sella turcica bridges in patients accepted for conventional orthodontic treatment and orthognathic surgery. METHODS: The pretreatment lateral cephalograms of 635 subjects scheduled for orthodontic treatment and 113 subjects scheduled for orthognathic surgery were used. The number of subjects with complete sella bridges and the type of discrepancy (Angle Class I, II, or III malocclusions, skeletal Class 2, 3 or bimaxillary protrusion) were recorded. RESULTS: Sella turcica bridges were found in 3.74 per cent of the total sample of 748 subjects. In the orthodontic group 3.21, 2.97 and 7.14 per cent of subjects in the Class 1, II and III subgroups respectively had sella bridges. In the orthognathic surgery group 2.86 and 10.71 per cent of the subjects in the Skeletal 2 and 3 subgroups respectively had sella bridges. No subjects in the bimaxillary subgroup had sella bridges. In the orthodontic group 2.20 per cent of the female subjects and 1.10 per cent of the male subjects had sella bridges, while in the orthognathic surgery group 1.77 of the females and 4.42 per cent of the males had sella bridges. CONCLUSIONS: Higher percentages of sella turcica bridges were found in subjects with Angle Class III and skeletal 3 discrepancies compared with subjects with Angle Class I, II, skeletal 2 or bimaxillary protrusion discrepancies.

Psychosomatic norm in orthodontics: problems and approach.

The term "psychosomatic norm" is not commonly used directly or indirectly in orthodontic discussions. However, at times, this may be the most important factor affecting patient satisfaction with treatment outcome. Psychosomatic norm is a norm based on a subjective psychosocial assessment of what is the patient's norm. A norm that significantly differs from the clinician's somatic norm, which is based on objective anatomic assessment, may end in a dilemma of unexplainable and unpredictable dissatisfaction with the orthodontic treatment outcome if not properly handled by the orthodontist. This review article attempts to approach and solve this clinically problematic situation.