A Cephalometric Study on the Relationship Between the Occlusal Plane, Ala-Tragus and Camper’s Lines in Subjects with Angle’s Class I, Class II and Class III Occlusion

Considering the importance of the occlusal plane orientation in complete denture prostheses, a study was conducted on the relationship between this plane with ala-tragus and Camper’s lines in soft tissue among individuals with class I, class II and class III occlusion. The aim of the present study was to define the best soft tissue index by which the location and inclination of the occlusal plane in complete dentures could be established. A total of 60 subjects were selected for the study. Lateral cephalograms of these subjects were obtained. Tracings and analysis was done to confirm to the skeletal relationship of subjects to be class I (normal), class II (prognathic maxilla) and class III (retrognathic maxilla). 20 Subjects of each group were screened for further analysis. Radiopaque markers were attached to the intended points on soft tissue and then standard lateral cephalograms were obtained from each subject. The angles between the following lines were measured: Occlusal line, Camper’s line (ala-porion), AT1 (ala-superior border of tragus), AT2 (ala-mid-tragus) and AT3 (ala-inferior border of tragus). The mean values and standard deviations were calculated for all the groups. The mean values calculated were subjected to repeated ANOVA test and significance was evaluated. Comparison of the results by the ANOVA test exhibited a significant difference. In class I subjects, it was evaluated that in 75 % individuals, the posterior reference point was found to be the mid-tragus; of class II subjects, in 60 % individuals, the posterior reference point was found to be the mid-tragus; and of class III subjects, in 75 % individuals, the posterior reference point was found to be the inferior border of tragus.     

Age Changes in Horizontal Condylar Angle: A Clinical and Cephalometric Study

Determination of condylar inclination is important when restoring the occlusal surfaces of teeth. It is important to know the changing trends in horizontal condylar inclination with age so as to have an idea about the cuspal morphology. Aims and objectives: a) to determine the effect of age changes in horizontal condylar inclination using articulator method and radiographic method (cephalometry) b) to compare the values of horizontal condylar inclination obtained using articulator method with that of cephalometric method c) to ascertain the symmetry of horizontal condylar angle on both right and left side on an articulator. 40 dentulous individuals with Angle’s class I occlusion were selected for the study. They were divided into four groups Group I: 20–29 years, Group II: 30–39 years, Group III: 40–49 years, Group IV: 50–59 years. Horizontal condylar inclination was determined on right and left side for each individual using protrusive interocclusal record in a Dentatus (ARL) semiadjustable articulator. Cephalometric recording was carried out twice on the left side, once in centric occlusion position and then in protrusive position. The two radiographs were superimposed to draw a line connecting the shifting position of condylion on an acetate tracing paper. This line when joined with Frankfurt horizontal plane gives the horizontal condylar inclination. Analysis of variance (ANOVA) revealed that there was a significant difference in horizontal condylar angle values in all the four groups which were statistically significant. There is a decrease in horizontal condylar angle values from Group I to Group IV. Horizontal condylar values obtained by articulator method and cephalometric method showed no significant difference for all the four groups tested. When horizontal condylar values obtained on right and left sides of Dentatus articulator were compared there was not much of a significant difference. Horizontal condylar values showed a decreasing trend with increasing age, i.e, as age advances there is a flattening of condylar head. Both articulator and cephalometric method yielded no significantly different values and hence both the methods can be used for determining condylar inclination. The difference in values of horizontal condylar angle on right and left sides were insignificant.     

The Position of the Occlusal Plane in Natural and Artificial Dentitions as Related to Other Craniofacial Planes

Purpose: This study aimed at determining the most reliable ala‐tragus line as a guide for the orientation of the occlusal plane in complete denture patients by use of cephalometric landmarks on dentate volunteers. Materials and Methods: Analysis was made for prosthodontically related craniofacial reference lines and angles of lateral cephalometric radiographs taken for 47 dentate adults. Variables were determined and data were analyzed using SPSS (SPSS, Inc., Chicago, IL). Results: Occlusal plane angle formed between the occlusal plane and Camper's plane had the lowest mean value in the angle formed with Camper's I, which represents the measure taken from the superior border of the tragus of the ear with a score of 2.1°. The highest was measured in the angle formed with Camper's III with a score of 6.1°, while the angle formed with Camper's II was 3.2°. The differences between the three planes in relation to the occlusal plane was significant (p < 0.001). Conclusion: The superior border of the tragus with the inferior border of the ala of the nose was most accurate in orienting the occlusal plane.     

Analysis of Relative Parallelism Between Hamular-Incisive-Papilla Plane and Campers Plane in Edentulous Subjects: A Comparative Study

The study was undertaken to evaluate the parallelism between hamular-incisive-papilla plane (HIP) and the Campers plane. And to determine which part of the posterior reference of the tragus i.e., the superior, middle or the inferior of the Camper’s plane is parallel to HIP using digital lateral cephalograms. Fifty edentulous subjects with well formed ridges were selected for the study. The master casts were obtained using the standard selective pressure impression procedure. On the deepest point of the hamular notches and the centre of the incisive papilla stainless steel spherical bearings were glued to the cast at the marked points. The study templates were fabricated with autopolymerizing acrylic resin. The subjects were prepared for the lateral cephalograms. Stainless steel spherical bearings were adhered to the superior, middle, inferior points of the tragus of the ear and inferior border of the ala of the nose using surgical adhesive tape. The subjects with study templates were subjected to lateral cephalograms. Cephalometric tracings were done using Autocad 2010 software. Lines were drawn connecting the incisive papilla and hamular notch and the stainless steel spherical bearings placed on the superior, middle and inferior points on the tragus and the ala of the nose i.e., the Campers line S, Campers line M, Campers line I. The angles between the three Camper’s line and the HIP were measured and recorded. Higher mean angulation was recorded in Campers line S –HIP (8.03) followed by Campers line M-HIP (4.60). Campers line I-HIP recorded the least angulation (3.80). The HIP is parallel to the Camper’s plane. The Camper’s plane formed with the posterior reference point as inferior point of the tragus is relatively parallel to the HIP.     

Orientation of craniofacial planes and temporomandibular disorder in young adults with normal occlusion

The aim of this study was to investigate the relationship between orientation of craniofacial planes relative to the true horizontal and temporomandibular disorder (TMD), in normal occlusion. Fourteen university dental students, with full natural dentition and bilateral Angle Class I occlusion, who exhibited signs and symptoms of TMD, were compared with 14 age- and sex-matched healthy controls. Frontal and lateral photographs were taken in natural head position with the subject standing up, clenching a Fox plane and having a facial arch positioned. Photographs were examined by a standardized image analysis. Inter-pupillary axis, Frankfurt, occlusal and Camper planes were evaluated. In frontal view, the Frankfurt plane was right rotated relative to the true horizontal both in TMD subjects (P < 0.01) and controls (P < 0.05), but rotation was larger in TMD subjects (mean difference between groups, 1.1 degrees, 95% confidence interval, 95% CI, 0.2-2.0 degrees ). No significant deviation from the horizontal or difference between groups was observed for the interpupillary axis and occlusal plane. In lateral view, the Frankfurt plane was upward-orientated relative to the true horizontal in TMD group (mean angular deviation 2.8 degrees, 95% CI, 1.0-4.6 degrees ). The occlusal and Camper planes were downward-orientated in both groups (P < 0.0001), but inclination of occlusal plane tended to be smaller in TMD subjects (mean difference between groups, -3.8 degrees, 95% CI, -7.6-0.1 degrees ). Angles between any craniofacial planes did not significantly differ between groups. The findings show that in young adults with normal occlusion, a weak association exists between the orientation of craniofacial planes in natural head position and signs and symptoms of TMD. Furthermore, they suggest that, within this population, TMD might be mainly associated with head posture rather than with craniofacial morphology.     

Bipolar Vessel Sealing System Versus Suture Ligation in Selective Neck Dissection

Aim

To evaluate whether the use of electrothermal bipolar vessel sealing system reduces the blood loss and operating time, with lesser complications as compared to suture ligation in selective neck dissection in patients with oral cancer.

Materials and Methods

The study was conducted in the Department of Oral and Maxillofacial Surgery of our institute from January 2015 to December 2016. The sample consisted of 60 patients, divided into Groups I and II with 30 subjects in each. In Group I electrothermal bipolar vessel sealer and in Group II suture ligation were used. The outcome measures recorded were: blood loss, operating time, quality of surgical field, postoperative pain on days 1, 2, and 3, drainage volume at 24, 48, and 72 h, edema, complications, and duration of hospital stay.

Results

There were 36 males and 24 females with a mean age of 50.76 ± 12.6 years. Blood loss was significantly less for Group I than for Group II (p = 0.001); the operating time was significantly less in Group I than in Group II (p = 0.001); Group I had better quality of surgical field (p = 0.001); less pain on postoperative evening, day 2 and day 3 (p < 0.05); and less drainage volume at 24 and 48 h (p < 0.05). Postoperative edema, complications, need for perioperative blood transfusion, and duration of hospital stay postsurgery were similar in both groups.

Conclusion

The electrothermal bipolar vessel sealer was efficacious in terms of reducing blood loss and operating time while providing a better surgical field and patient compliance without increasing the perioperative morbidity.

     

Anteroposterior skeletofacial classification and its relationship to maxillary second molar buccopalatal angulation

ObjectiveTo compare second molar angulation to the occlusal plane with cephalometric measurements corresponding to AP skeletal discrepancy.Materials and Methods72 patients'' pre-orthodontic records were analyzed. A plane was constructed along the cusps of the upper second molar and measured to a proxy for the occlusal plane. The angle between the planes was measured. ANB, Wits appraisal, U1-SN, IMPA, A-B perpendicular to Frankfort, and overjet were measured on the patients'' cephalograms. Generalized additive mixed model analysis was performed to analyze the relationship between the second molar angulation and the cephalometric measurements.ResultsAll six cephalometric measurements showed a significant relationship with the second molar angulation, with Class III patients having a larger angle than Class II and I patients.ConclusionsClass III patients have upper second molars that are significantly tipped from the occlusal plane. The second molars require special attention for correction prior to orthognathic surgery for Class III patients in order to avoid deleterious effects from the malpositioned teeth.     

Effects of tooth loss on brain structure: a voxel-based morphometry study

Purpose

One of the most prominent issues in a super-aging society is the rapid increase in dementia patients. Cross-sectional studies in dentistry have indicated that patients with dementia have worse oral health compared to healthy people. The purpose of this study was to clarify the influence of tooth loss on brain structure by comparing the volumes of gray matter (GM) and white matter (WM) between edentulous and dentulous subjects.

A cephalometric comparison of horizontal and vertical skeletal parameters in North and South Indian population groups

A cephalometric study was carried out to compare skeletal parameters between North Indian (Group A) and South Indian (Group B) population. Sixty subjects in the age group of 16–21 years with acceptable profile, class I molar and canine relationship were selected. Cephalometric records were obtained for both the groups (A&B) and digitized. SNA, SNB, Wits appraisal (AO-BO), Mandibular Base (Go-Pog), Maxillary Base (PNS-Point A), Effective Mandibular Length (Co-Gn) and Mid-Facial Length (Co-Point A) readings were assessed to determine any difference in horizontal parameters. Similarly, Y-axis, Mandibular Plane Angle (MPA), Mandible to Cranial Base (FMA), Gonial Angle (GA), Upper and Lower Gonial Angle of Jarabak (UGA & LGA), Total Facial Height (TFH), Upper anterior Facial height (UAFH), lower anterior facial height (LAFH), Posterior Height/Total Anterior Height Ratio (PH/TAH) were digitized to find any difference in vertical parameters. Statistical analysis using paired t-test was done with level of significance less than 5%. Results showed that, South Indian girls had more MPA and FMA compared to the North Indians suggesting a tendency towards vertical growth pattern. This cephalometric appraisal study shall enable an orthodontist in formulating an optimal treatment plan for the two population groups.     

Cephalometric: Evaluation of Influence of Edentulousness on Mandibular Morphology: A Comparative Study

Mandible undergoes several dimensional changes due to aging accompanied with gradual loss of teeth. There is marked alterations in shape and dimensions of the parts of the mandible associated with complete or nearly complete loss of dentition. The purpose of this study was to analyze the effect of loss of dentition on the dimensions of mandible using lateral cephalogram. The study group comprised of 35 dentulous subjects (age range 25–30 years) and 35 edentulous subjects (age range 45–65 years), with a period of edentulousness of 1–5 years. Subjects were selected based on certain selection criteria and lateral cephalograms were taken. Lateral cephalograms were traced and the values obtained were statistically analyzed using T test. On statistical analysis it was found that the thickness of condylar process and corpus were reduced in edentulous subjects. Length of mandible, ramus and corpus were reduced in edentulous subjects when compared to dentulous subjects. Gonial angle was more obtuse in edentulous subjects. Reduction in thickness of condylar length and length of mandible were negatively correlated to duration of edentulousness. It can be concluded that mandible undergoes significant dimensional changes as a result of loss of teeth.     

A Comparative Study of Mandibular Incisor Relation to the Lingual Frenum in Natural Dentition and in Complete Denture Wearers

The determination of the occlusal vertical dimension and proper positioning of the anterior teeth are major factors in making complete dentures which will give optimum service. In this study, efforts were made to evaluate the reliability of measurement of vertical distance between the anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors in natural dentition among different age groups and in complete denture wearers. Three hundred dentulous subjects belonging to different age groups and hundred edentulous patients wearing complete dentures were selected. The dentulous group was divided into three groups, group I (20–40 years), group II (41–60 years), group III (61 years and above) and the edentulous subjects being group IV ( 40–60 years). Mandibular irreversible hydrocolloid impression (Alginate) was made using modified stock tray. In edentulous subjects impression was made with denture in position. The vertical distance between anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors was measured on the dentulous casts and casts of complete denture wearer using dental surveyor and the vernier calipers. The values were tabulated and statistically analysed. The mean vertical distance between anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors among dentulous subjects was 12.3 mm and among complete denture wearers was found to be 13.2 mm. There was no significant variation in the mean vertical distance among dentulous subjects belonging to different age groups. At 5 % significance level, statistically there was a significant difference in the mean vertical distance between group I and group IV; group II and group IV.     

Comparison of Micromarsupialization and Modified Micromarsupialization for the Management of Mucocoele of Lower Lip: A Prospective Randomized Clinical Trial

Background

This study was undertaken to compare micromarsupialization and modified micromarsupialization for the management of mucoceles.

Materials and Methods

A prospective randomized clinical study was done on thirty patients having mucocele on lower lip. In Group A (n = 15), micromarsupialization and in Group B (n = 15), modified micromarsupialization technique was used. The outcome variables were duration of surgery, intraoperative pain, postoperative pain, healing and recurrence. t test and p values were used to compare the age, duration of lesion, duration of treatment and time taken for healing. The results were expressed as mean with SD. Statistical significance was established at the p ≤ 0.05 level. Analysis of pain (intraoperative, on 3rd, 7th day), intraoperative bleeding and recurrence was done using Fischer’s exact test (p = 0.875, NS).

Results

The average duration of treatment for Group A was 4.10 ± 0.39 min and for Group B was 5.33 ± 0.2 min. The difference was found to be statistically highly significant (p value ≤0.000). The observed power was 1.000. The difference in the intraoperative and postoperative pain on 3rd and 7th day was not found to be significant as per Fischer’s exact test. The mean time taken for healing of the surgical site in Group A was 7.47 ± 0.64 days and in Group B was 9.87 ± 1.88 days, and the difference was found to be highly significant. The observed power was 0.995.

Conclusions

Modified micromarsupialization appears to be a safe technique for the management of mucoceles. However, in comparison with micromarsupialization, it has a higher operating and healing time.

     

Relationship between occlusal force and condylar morphology in class II and III after bi-maxillary osteotomy

Purpose

The purpose of this study was to examine the relationship between occlusal force and condylar morphology in class II and III after sagittal split ramus osteotomy (SSRO) with Le Fort I osteotomy.

Changes in cross-sectional measurements of masseter,medial pterygoid muscles,ramus, condyle and occlusal force after bi-maxillary surgery

Purpose

The purpose of this study was to examine changes in masseter and medial pterygoid muscles, ramus, condyle and occlusal force after bi-maxillary surgery in class II and III patients.

Errors in mounting maxillary casts using face-bow records as a result of an anatomical variation

The relationship of the teeth to the intercondylar axis and horizontal plane is transferred to the articulator by means of a face-bow record. In most semi-adjustable articulators, the horizontal plane to which the maxillary cast is orientated is the Frankfort plane or its near equivalent, the orbital-axis plane. For this purpose the infraorbital notch is used as the anterior reference point Clinical observations of Cantonese patients suggest that in some individuals the Frankfort plane may not be horizontal, with the result that the orientation of the casts in the articulator is incorrect with respect to the horizontal plane, and a preliminary study has been undertaken to investigate this range of variation.

Lateral cephalometric radiographs were taken of 33 Cantonese male adult subjects in natural head posture. The cephalometric landmarks of the Frankfort plane were recorded relative to the true vertical axis and, by the use of a digitizer, fed into a computer for analysis. The results show that there is considerable individual variation in the orientation of the Frankfort plane. Variations ranging between +11° and -2° in relation to the horizontal were recorded. Large anatomical variations may make errors difficult to avoid when the manufacturers' recommended anterior reference point for a particular face-bow is the infraorbital notch. Clearly this is a source of potential error which should be recognized when treating this ethnic group.     

Prevalence and location of accessory foramina in the human mandible

Objective

This study aimed to radiographically assess the prevalence and location of accessory foramina in the human mandible using helical computed tomography (CT) images and three-dimensional reconstructions.

Methods

Helical CT images from 24 males and 22 females aged 66–88 years (mean age: 73.7 ± 5.3 years) were observed. Each image was assessed in the three anatomical planes, and three-dimensional reconstructions were performed with Amira 5.6 software.

Results

All subjects (n = 46) presented at least one accessory foramina. A lingual foramen was the most frequently observed foramen and present in 96 % (n = 44) of subjects. Mandibular anterior nutrient canals were clearly observed in 72 % (n = 33) of subjects (71 %, n = 17, of males; 73 %, n = 16, of females). A retromolar foramen was present in 17 % (n = 8) of subjects (21 %, n = 5, of males; 14 %, n = 3, of females). A double mental foramen (DMF) was present in only one subject (2 %). Fifty percent (n = 23) of subjects presented one or more inferior retromental foramen (IRF). No significant correlations were observed between prevalences of accessory foramina and sex.

Conclusions

The lingual foramen can be considered a constant finding, and mandibular anterior nutrient canal foramina and IRF were present in the majority of subjects. Retromolar foramina and DMF were less common but can be associated with anesthetic failures and oral surgery complications. Three-dimensional reconstructions provided better understanding of the locations of foramina and their interrelations with the anatomy of the jaw.

     

A study of the occlusal plane orientation in complete denture construction

A cephalometric study was conducted on eighteen dentulous subjects and fifty-six complete denture wearers to determine the location of the natural and artificial occlusal planes as related to Camper's plane. The results indicated that both the natural and artificial occlusal planes were not parallel to Camper's plane. However, the final anteroposterior inclination of the artificial occlusal plane in complete dentures was almost the same as the inclination of the natural occlusal plane.     

Botulinumtoxin zur Behandlung des gustatorischen Schwitzens

Background

Botulinum toxin A has meanwhile become a proven method for treatment of gustatory sweating (focal hyperhidrosis, Frey’s syndrome). Clear-cut recommendations regarding dosage of botulinum toxin A in Frey’s syndrome are currently not available. The aim of this prospective randomized study therefore was to investigate botulinum toxin A with respect to its efficacy in Frey’s syndrome, the ideal dose yielding maximal duration of the effect, and patient contentedness as well as unwanted side effects in patients of the Clinic of OMF Surgery at the Ruhr-University of Bochum.

Patients and method

Twenty patients suffering from severe Frey’s syndrome as a result of operations of the parotid gland were examined with the starch iodine test according to Minor. The gustatory skin areas were re-examined after intracutaneous injection of botulinum toxin A for up to 1 year. The patients (n=20) were randomly assigned to two different treatment groups (group I: 2 MU/cm², n=10; group II: 3 MU/cm², n=10).

Results

Mean sweating skin areas in the two treatment groups ranged between 39±9 and 32±12 cm², respectively. A single injection of 3 MU botulinum toxin A resulted in a nearly complete blockade of gustatory sweating for the observation period of 1 year. In the group treated with 2 MU botulinum toxin A, 44% of the total gustatory skin areas were still sweating, thus necessitating a second injection of botulinum toxin A in these patients.

Conclusion

Intracutaneous injection of botulinum toxin A represents a highly effective and minimally invasive procedure for the treatment of Frey’s syndrome. This study shows for the first time that a dosage of 3 MU/cm² of botulinum toxin A achieves a complete and reliable blockade of gustatory sweating lasting for at least 12 months. This dose may therefore be recommended for treatment of this syndrome.     

The effect of maximum bite force on marginal bone loss of mini‐implants supporting a mandibular overdenture: a randomized controlled trial

Objectives: To evaluate the effect of maximum bite force (mBF) on marginal bone loss (MBL) around mini‐implants in edentulous patients wearing mandibular overdentures with two retention systems: ball and bar. Material and methods: Forty‐five totally edentulous patients were selected from a public health center. All of them received two mini‐implants (1.8 × 15 mm; Sendax^®) in the anterior mandible using a minimally invasive technique. A single randomization was performed to allocate the patients in two groups. Group I (n=22) received two single ball‐type mini‐implants and Group II (n=23) received two mini‐implants splinted with a prefabricated bar. The mBF was recorded using a press‐sensitive sheet Dental Prescale^® (Fuji) and MBL using standardized radiographs of each mini‐implant at the baseline and 5, 7, 10, and 15 months after surgery; the values were compared between groups. Results: Two members of Group I failed to complete the study, decreasing the number of participants to 20. There was no relationship between the mBF and the MBL of the mini‐implants (Spearman's ρr_s=0.147; P=0.378). At the 15‐month follow‐up, the average mBF for Group I (ball) was 247.53 ± 132.91 N and that of Group II (bar) only 203.23 ± 76.85 N (Mann–Whitney test; P=0.586). The MBL values were also higher for Group I (1.40 ± 1.02 mm) than Group II (0.84 ± 0.66 mm) during the entire 15‐month follow‐up period (Mann–Whitney test; P=0.077). Conclusions: No relationship was found between mBF and MBL for patients wearing overdentures retained on mini‐implants using bar or ball attachment systems. To cite this article:
Jofré J, Hamada T, Nishimura M, Klattenhoff C. The effect of maximum bite force on marginal bone loss of mini‐implants supporting a mandibular overdenture: a randomized controlled trial.
Clin. Oral Impl. Res. 21 , 2010; 243–249.
doi: 10.1111/j.1600‐0501.2009.01834.x