- Replacement of a first molar and 3 second molars by the mesial inclination of 4 impacted third molars in an adult with a Class II Division 1 malocclusion. [Case Reports]
- AJAm J Orthod Dentofacial Orthop 2015; 147(6):755-65
- This case report presents the successful replacement of 1 first molar and 3 second molars by the mesial inclination of 4 impacted third molars. A woman, 23 years 6 months old, had a chief complaint o…
This case report presents the successful replacement of 1 first molar and 3 second molars by the mesial inclination of 4 impacted third molars. A woman, 23 years 6 months old, had a chief complaint of crowding of her anterior teeth and linguoclination of a second molar on the left side. The panoramic radiographic images showed that the maxillary and mandibular third molars on both sides were impacted. Root resorption on the distal surfaces of the maxillary second molars was suspected. The patient was given a diagnosis of Angle Class II Division 1 malocclusion with severe crowding of the anterior teeth and 4 impacted third molars. After we extracted the treated maxillary second premolars and the second molars on both sides, the treated mandibular second premolar and the second molar on the left side, and the root canal-filled mandibular first molar on the right side, the 4 impacted third molars were uprighted and formed part of the posterior functional occlusion. The total active treatment period was 39 months. The maxillary and mandibular third molars on both sides successfully replaced the first and second molars. The replacement of a damaged molar by an impacted third molar is a useful treatment option for using sound teeth.
- Posterior scissors-bite: masticatory jaw movement and muscle activity. [Journal Article]
- JOJ Oral Rehabil 2014; 41(4):257-65
- Scissors-bite is a malocclusion characterised by buccal inclination or buccoversion of the maxillary posterior tooth and/or linguoclination or linguoversion of the mandibular posterior tooth. This ty…
Scissors-bite is a malocclusion characterised by buccal inclination or buccoversion of the maxillary posterior tooth and/or linguoclination or linguoversion of the mandibular posterior tooth. This type of malocclusion causes reduced contact of the occlusal surfaces and can cause excessive vertical overlapping of the posterior teeth. This case-control study is the first to evaluate both masticatory jaw movement and masseter and temporalis muscle activity in patients with unilateral posterior scissors-bite. Jaw movement variables and surface electromyography data were recorded in 30 adult patients with unilateral posterior scissors-bite malocclusion and 18 subjects with normal occlusion in a case-control study. The chewing pattern on the scissors-bite side significantly differed from that of the non-scissors-bite side in the patients and of the right side in the normal subjects. These differences included a narrower chewing pattern (closing angle, P < 0.01; cycle width, P < 0.01), a longer closing duration (P < 0.05), a slower closing velocity (P < 0.01) and lower activities of both the temporalis (P < 0.05) and the masseter (P < 0.05) muscles on the working side. In 96% of the patients with unilateral posterior scissors-bite, the preferred chewing side was the non-scissors-bite side (P = 0.005). These findings suggest that scissors-bite malocclusion is associated with the masticatory chewing pattern and muscle activity, involving the choice of the preferred chewing side in patients with unilateral posterior scissors-bite.
- [Correction of linguoclination or buccoclination of the mandibular molar with simple semi-fixed lingual arch]. [Journal Article]
- SKShanghai Kou Qiang Yi Xue 2004; 13(2):155-7
- CONCLUSIONS: The simple semi-fixed lingual arch can fix properly the buccolingual position of the mandibular molar and can shorten the course of the fixed orthodontic therapy. In addition,this method exerts less impact on the contour of the anterior mandibular arch.
- [The influence of playing the clarinet on the dentomaxillofacial morphology and function]. [Journal Article]
- ODOu Daigaku Shigakushi 1990; 17(2):131-54
- The purpose of this experiment is to understand the influence of playing the clarinet on the dentomaxillofacial morphology and function. The 12 subjects, selected at random (all adults, 4 men and 8 w…
The purpose of this experiment is to understand the influence of playing the clarinet on the dentomaxillofacial morphology and function. The 12 subjects, selected at random (all adults, 4 men and 8 women) had played the clarinet for more than 10 years. The subjects had anamnesis, oral photo pictures, facial photo pictures, cast model, lateral cephalograms (lateral cephalo) and frontal cephalograms (frontal cephalo) taken when they were in centric occlusion and playing the clarinet. The results were as follows: 1. The facial profile and occlusal relation depend on the subjects. (2 mandibular retrognathism. 4 prognathism and 6 crowding.) 2. No characteristic skeletal pattern was found compared with controls in angle measurement but subjects had a tendency to have large facial height in linear measurement of lateral cephalo. And in denture pattern the lower incisors were linguoclination. 3. Concerning the lateral cephalo, we noticed that the angle of the clarinet in relation to the body axis increased in accordance with the prognathism and decreased with the retrognathism. 4. The subjects don't have identical midline, comparing lower midline to dentofacial midline, when playing, the angle of clarinet to the body was eccentric according to maxillary incisors in frontal cephalo. 5. Anterial and posterial length was short in mandibular arch, analyzing the cast model. 6. The pressure on mouthpiece increased in accordance with the prognathism and decreased with retrognathism. 7. The results of the EMG analysis indicated that the muscle activity of oral sphincter was described as 1). upper lip, 2). lower lip, 3). commisure of lips and differences were found depending on the parts being studied and the sound played on the clarinet. In conclusion, the skeletal and denture problem influence the holding position of the clarinet, embouchure and the way of playing it. In case of mandibular prognathism, when playing, the subjects pressed on their teeth with the clarinet. So B instrument won't do for prognathism because lower incisors are pushed inward as a result.