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At least 145 records · Page 8Linked to original sources
PubMed2005

Facial and oral reconstruction following trauma and failed chin implant: a case report.

Functional and esthetic reconstruction of a patient with microgenia who sustained traumatic injury was successfully accomplished using Brånemark System osseointegrated implants (Nobel Biocare USA, Inc., Yorba Linda, CA) to support a permanent dental prosthesis following mechanical and biologic reconstruction of the anterior mandible and chin. A 25-year-old glycine chin implant previously used for facial esthetic enhancement had eroded the anterior cortical plate and migrated through the medullary bone, compressing the periosteum into the apex of the anterior tooth roots. Further destruction of the lingual cortex with risk of fracture was imminent. After removal of the chin implant, a cancellous bone graft was held in place with a titanium mesh frame. The prosthetic rehabilitation consisted of two phases of mandibular implant placement followed by the construction of a porcelain-fused-to-gold implant-supported fixed prosthesis, restoring the occlusal vertical dimension as well as appropriate lip support. Restoration of function was superior to the pretreatment condition.

Bone Resorption↗
PubMed2003

Chin augmentation with conchal cartilage.

Profile enhancement most frequently involves mentoplasty. For this purpose, the author performs conchal grafts to the chin. A total of 28 women aged 15 to 76 years (mean age, 38.11 +/- 15.11 years) requested mentoplasty by itself or combined with rhinoplasty, rhytidoplasty, or submental lipoplasty. The conchal cartilage was harvested subperichondrally through a posterior 3-cm incision. The specimen measured 3 x 1 cm, which was sufficient to project the chin 2 to 3 mm. For 4 to 5 mm of projection, both cartilages were used. The graft was positioned under the periosteum and held with two 5-0 nylon sutures. In these cases, the conchal cartilage graft was a suitable option for chin augmentations up to 5 mm.

Adolescent↗
PubMed2003

Chin surgery III: revelations.

This article is a logical extension of previous articles written on the topic of aesthetic chin surgery. In it, the authors expand on previously published surgical techniques and provide specific updates to increase success in some unusual situations. They review the indications for and uses of reduced-height implants, discuss the validity of centralized chin incisions in both reconstruction and revisions, show the diversity of mentalis muscle anatomy and chin pad variations, reveal the importance of the lip-to-labiomental crease inclination in cases of macrogenia, note a key update on reefing the mentalis muscle to a higher position for permanent sulcus position, discuss the issues of lower lip position and lower incisor show, and expound on the horizontal smile/chin ptosis phenomenon.

Chin↗
PubMed2003

Improving aesthetic outcomes after alloplastic chin augmentation.

A novel approach to increase chin projection with alloplastic material is presented. Key aspects of the technique include the consideration of anthropometric normal values in preoperative assessment and planning, a submental approach with wide subperiosteal exposure of the area to be augmented, the use of two-piece porous polyethylene implants for augmentation, and screw fixation of the implant to the mandible. Screw fixation improves the predictability and precision of reconstruction by preventing implant displacement, by obliterating gaps between the implant and the facial skeleton, and by facilitating final implant contouring. In a series of 46 patients (24 primary and 22 secondary) operated on over a 6-year period, this approach allowed anatomically correct, stable chin contours to be created. Iatrogenic problems with macrogenia, mentalis dysfunction, and soft-tissue distortion resulting from implant migration and capsular contracture have been avoided. There have been no infections. Two patients who had had multiple previous chin operations requested revisional surgery to refine contour.

Adolescent↗
PubMed1981

Jaw muscle silent periods by tooth tap and chin tap.

Electromyographic silent periods from jaw closing muscles were elicited during a clench by tapping on the chin and on selected teeth both in asymptomatic subjects and in subjects reporting symptoms of temporomandibular joint dysfunction. The mean duration in response to a chin tap was significantly shorter in the asymptomatic group than in the dysfunction group. No significant differences in mean duration elicited by tooth taps were found between groups. Other comparisons of mean durations such as among muscles, among teeth, or between chin taps and tooth taps failed to achieve statistical significance.

Chin↗
PubMed1991

Trembling chin--a report of this inheritable dominant character in a four-generation Canadian family.

Trembling chin is an unusual, benign, dominant trait. We describe the condition in a four-generation Canadian family. Investigations, which included E.E.G., electromyograph and facial nerve conductance studies on affected and unaffected individuals, were normal. Premature hearing loss, present in all affected members of this family over age 50, strongly suggests an association of trembling chin with otosclerosis. The merits of early diagnosis and preventive treatment for otosclerosis in persons affected by trembling chin are discussed.

Canada↗
PubMed1995

The stability of facial osteotomies. 3. Chin advancement.

Surgical repositioning of the chin can be used to improve function and aesthetics. The most commonly employed technique involves a sectioning of the lower border of the anterior mandible, thus allowing a sliding movement of the chin. It is generally accepted that the maintenance of a soft tissue attachment provides a clinically stable skeletal and predictable soft tissue change with minimal postoperative osseous resorption. Part 3 of this series of papers addresses the issues of treatment planning, surgical technique and clinical indications for undertaking advancement genioplasty. These, combined with the surgeon's artistic sense of facial harmony, are pre-conditions necessary for successful chin surgery.

Adolescent↗
PubMed1996

The stability of facial osteotomies. Part 6. Chin setback.

Isolated horizontal osteotomy of the anterior mandible (genioplasty) to move the chin posteriorly can be used to improve facial profile. There has been an increasing tendency in practice to carry out this procedure in combination with maxillary and/or mandibular surgery. This is most appropriately undertaken when pre-operative prediction techniques indicate that chin prominence will remain excessive following maxillary and/or mandibular advancement surgery. This paper reviews surgical techniques applicable to posterior movement of the chin ("the setback genioplasty') and illustrates the clinical results achieved with its use.

Adolescent↗
PubMed1980

A cineradiographic study of chin marker positioning: implications for the strain gauge transduction of jaw movement.

Three normal adult subjects were filmed using lateral-view, high-speed cineradiography to measure the amount of movement of external skin points on the jaw relative to the underlying jaw bone. Metal markers were secured to the skin to simulate cantilever beam attachment points commonly utilized in the strain gauge transduction of jaw movements. Standard deviations of chin marker movement relative to the jaw ranged from 0.52 to 1.28 mm in an anterior-posterior direction and 0.67 to 2.31 mm in a superior-inferior direction. Lower lip and chin marker positions were highly correlated in the superior-inferior direction. Chin marker positions tended to be more superior and, in one subject, more anterior for labial than for nonlabial different contexts. The degree of variability was not systematically different for the two different contexts.

Adult↗
PubMed2004

The effects of chin lift and jaw thrust while in the lateral position on stridor score in anesthetized children with adenotonsillar hypertrophy.

Obstruction of the upper airway is a major challenge for anesthesiologists administering general anesthesia in spontaneously breathing patients, especially in pediatric anesthesia with adenotonsillar hypertrophy. Lateral positioning is a simple treatment for obstructive sleep apnea and also decreases collapsibility of the pharynx in anesthetized adults with obstructive sleep apnea. In this study, we examined the effects of body position shifting and common airway maneuvers, such as chin lift and jaw thrust, on airway patency (stridor score) in anesthetized children scheduled for adenotonsillectomy. Thirty children aged 1-10 yr were anesthetized with sevoflurane. During spontaneous breathing of 5% sevoflurane, stridor score was recorded. After baseline recording, chin lift and jaw thrust were performed on patients in both the supine and the lateral decubitus positions. Chin lift and jaw thrust improved the stridor score. Furthermore, lateral positioning dramatically enhanced the effects of these airway maneuvers on airway patency. Jaw thrust combined with lateral positioning provided easy airway management for the anesthesiologists. We conclude that lateral positioning combined with airway maneuvers significantly improved airway patency compared with the airway maneuvers alone for patients in the supine position.

Adenoidectomy↗
PubMed1995

Outcome analysis of Mohs surgery of the lip and chin: comparing secondary intention healing and surgery.

Wounds of the lip and chin resulting from microscopically controlled (Mohs) surgery are often repaired immediately. However, wounds allowed to heal by secondary intention have the advantage of optimal cancer surveillance, simplified wound care, and avoidance of the costs and potential complications associated with reconstructive procedures. Accurate prediction of the course of wound healing would allow a rational approach to selection of surgery or healing by secondary intention. The authors evaluated 105 patients with defects of the lip and chin after Mohs excision for cancer who healed by secondary intention. Forty-six patients treated surgically were followed for comparison. The lip and chin were divided into subunits and the wound location, size, and depth were recorded. Patients were followed at intervals and a final determination regarding cosmesis was made after 6 or more months. It is concluded that the final cosmetic result can be confidently predicted on the basis of location by subunit, size, and depth of the wound.

Adult↗
PubMed2003

Correction of the ptotic chin.

Where there is extensive stripping of the mentalis muscle from the mandible during vestibuloplasty procedures the chin tissues often become lax and droop, giving an unsightly ptotic defect. If this soft-tissue defect is combined with excessive chin tissue an excisional surgical procedure is required. This article describes a surgical procedure to produce an acceptable chin profile.

Chin↗
PubMed2005

Morbidity of chin bone transplants used for reconstructing alveolar defects in cleft patients.

OBJECTIVE: The aim of this study was to evaluate the objective and subjective morbidity of symphyseal chin bone harvesting used for reconstruction of alveolar defects in young cleft patients. DESIGN: All patients who had undergone chin bone harvesting for alveolar cleft reconstruction in the period from 1992 through 2000 at the Department of Oral and Maxillofacial Surgery of the University Hospital Groningen, Groningen, The Netherlands, were invited to participate in this retrospective study.Patients' acceptance, perioperative and postoperative morbidity were evaluated. A survey of the medical records was performed. In addition, the patients completed a questionnaire for their appreciation of the procedure. They were also subjected to a clinical and radiographic examination. PATIENTS: Thirty patients (21 males and 9 females; mean age 11.8 +/- 3.6 years) participated in this study. RESULTS: Neither the medical records nor the experiences of the patients showed significant morbidity. The procedure was appreciated with 6.8 +/- 3.5 (scale 0 to 10). Postoperative pain was scored as 1.2 +/- 2.5 (scale 0 to 10). Three patients reported transient sensory disturbances at the donor site. Two patients showed a slight sensibility disorder in the symphyseal region. In three patients, an endodontic problem had developed in a lower incisor. CONCLUSION: This study showed that chin bone harvesting for reconstructing alveolar cleft in young patients is a well-accepted procedure with low objective and subjective morbidity. Notwithstanding this low morbidity, the patients (and their parents) have to be informed about the risk of objective and subjective disturbances of the sensibility in the donor region and the risk of dental pulp necrosis.

Adolescent↗
PubMed1980

Jaw muscle activity during chin-tapping.

Electromyographic (EMG) activity was recorded from the masseter, the anterior temporal and the anterior digastric muscle on the right side of ten dental students when taps were administered upwards or downwards to the chin. The experiment was performed both with relaxed jaw muscles and with contracting depressor muscles. Pairs of intracutaneous platinum hook electrodes were used for the masseter and temporal muscles while concentric needle electrodes were inserted into the anterior digastric muscles. The mean latency of the jaw-jerk elicited in the relaxed masseter muscle when tapping downwards on the chin was 7.8 msec and in the temporal muscle 8.4 msec. The corresponding values of the latency during jaw opening against resistance from the investigator's finger was 8.2 msec and 9.0 msec. During upward tapping on the chin recordings from the anterior digastric muscle showed obvious changes in EMG activity, the latency ranging from 13 to 34 msec. Thus, compared to the latency of the jaw-jerk in the masseter and temporal muscles, which contain numerous muscle spindles, recordings from the anterior digastric muscle, where muscle spindles are thought to be either lacking or few in number, showed no signs of a monosynaptic reflex.

Adult↗
PubMed1998

The effects of zygomatic and chin augmentation on facial aesthetics.

The most obvious and prominent parts of the facial anatomy which affect aesthetics are the nose, the prominence of the zygoma and the chin. These three structures are extremely important when assessing facial aesthetics, and whilst basal structures of the maxilla and mandible are important, it is the positioning of the zygoma, nose and chin which ultimately are the determining factors of good facial aesthetics. This paper outlines the various methods of zygomatic and chin augmentation and describes the intra-oral approach to performing an osteotomy of the zygoma. These procedures are commonly performed in association with orthognathic surgical procedures to correct the occlusion and can be carried out primarily with the initial surgery, or secondarily for aesthetic enhancement.

Bone Transplantation↗
PubMed2001

[Hyperactivity of the muscles of the lip and chin and indications for surgery to reduce it].

Hyperactivity of the muscles controlling the lower lip and chin (muscles of the chin, buccinator, orbicularis, etc.) can be demonstrated at different levels of the muscular complex and may act as an elastic force against the mandibular alveolar process. Dysfunction in this region may lead to reduction of the alveolar bone quantity, reducing the tooth-bone equilibrium. If this balance is disturbed, periodontal lesions, a lower incisal crowding and a retrognathic mandibular process may result. Surgery to correct overactivity of the chin muscles is described here step by step. Resection of the muscles may be undertaken on a greater or lesser scale and striation of the muscle may also allow reduction of muscular strength. Reducing the muscular activity creates a better environment for the development of the mandible and its alveolar process. Depending on the clinical situation, these techniques can be associated with genioplasty, bone graft and/or mandibular orthognathic surgery.

Alveolar Bone Loss↗
PubMedDate not supplied

Microscopic analysis of reconstructed maxillary alveolar ridges using autogenous bone grafts from the chin and iliac crest.

PURPOSE: The aim of this study was to histologically analyze the bone repair of maxillary areas reconstructed with autogenous bone grafts using 2 different donor sites, the ilium and the chin. MATERIALS AND METHODS: Specimens were retrieved with trephine burs positioned transversely in augmented ridges 4 months after placement of the grafts. To analyze bone conditions, a histomorphometric study of ground sections was performed using a special template to identify 3 specific regions of the specimens: cortical bone, cancellous bone, and the region of transition between the alveolar ridge and the graft. Ten patients, 5 men and 5 women, with a mean age of 47 years (range 28 to 67) were evaluated. RESULTS: Results indicated good incorporation of the grafts in this period, demonstrated by intense osteogenesis indicating an active remodeling process. DISCUSSION: In both groups, the improvement in bone quality of the receptor site was evident, independent of the size of the reconstruction, although chin grafts presented better bone quality. CONCLUSIONS: From this study it was possible to conclude that a period of 4 months is sufficient for the placement of osseointegrated implants in reconstructed areas, where chin or iliac autogenous grafts have been used.

Adult↗