Can costochondral grafts fulfil ramus-condyle unit reconstruction goals in children with temporomandibular joint ankylosis?

The purpose of this study was to analyse whether costochondral grafts (CCG) fulfil temporomandibular joint (TMJ) reconstructive goals in children with TMJ ankylosis. A total of 23 patients (12 male, 11 female, aged 3–16 years) with unilateral or bilateral TMJ ankylosis operated on between January 2014 to April 2018 were included in the study. Maximal incisal opening (MIO), frequency of reankylosis, and growth of CCG, were evaluated at one month and six months for one year, and after that once yearly. Mouth opening changes with time were assessed by the Friedman test and growth was compared at follow up and analysed using the paired t test. Mean (range) follow up was 18 (12–48) months. Study results revealed follow up MIO at 12 months was highly significant (p = 0.001). Out of 27 CCG studied, only one graft had undergone re-ankylosis. Based on the predetermined criteria using condylion to gnathion (Co–Gn) measurement in the posteroanterior cephalogram, CCG were categorised into optimum, sub-optimum, and overgrowth. However, long-standing TMJ ankylosis cases still displayed mandibular asymmetry at the end of the study, even with “optimal growth” radiographically. Overall comparison between the immediate postoperative and last follow up Co-Gn measurements in either unilateral or bilateral cases was not significant. CCG with functional matrix maintained the growth of the mandible and MIO in TMJ ankylosis. It can be concluded that CCG partially fulfils reconstructive goals; however, patients need to be followed up till the end of puberty for a substantive conclusion.     

Is it necessary to treat incisal protrusion in Tunisian children?

It is thought that incisor protrusion could be ethnic-related because Tunisians, as Africans, might reflect the genetic influence of the incisal protrusion of their darker skinned neighbors. We first compiled local standards by determining the normal incisor positions of children of the Sfax region with balanced facial patterns. We selected 95 teenagers from 5 different high schools in Sfax (average age: 16 years 9 months), all having a normal dentition and a balanced facial pattern. This first study showed that upper and lower incisors were protruded 3 mm beyond American standards. Second, we studied incisor stability after four-first bicuspid extraction treatment. We selected 26 patients all having Class I molar relationships and upper and lower incisor protrusion. We compared x-ray incisor measurements of 3 radiographs: before treatment, after treatment and 2 or 3 years post-treatment. This study shows that incisor relapse ranges between 20 and 30%.     

Stoppers in RED II distraction device: is it possible to prevent pin migration?

Distraction osteogenesis has become popular for the treatment of hypoplastic congenital craniomaxillofacial anomalies. Rigid external distraction (RED II) after Le Fort III osteotomy was shown to be a highly effective treatment for the management of midface hypoplasia. This device is used with a halo vest, which is placed at the cranial equator. Intracranial penetration of the fixation pins of the halo is one of the complications of an external distraction device. To prevent pin penetration in rigid external distraction, the authors designed polylactic acid/polyglycolic acid (PLA/PGA) plates that were circular; the plates were 0.8 cm in diameter and had 1.5-mm holes in the center, through which the tip of the pins would pass. To quantify the applied torque by manual tightening of the screws of the distraction device and to measure intraosseous cone depth created by the penetration of the conical part of the screws with and without the PLA/PGA composite stopper, first an in vitro experiment was undertaken on cadaver. Then these PLA/PGA plaques, or stoppers, were placed over the bone surfaces of the cranium of the patients where the tip of the pins press. PLA/PGA stoppers are malleable and adapt their shape to the interactive forces between bone and the pins. They act as a second barrier, and spread the pressure of the screws to larger surfaces, thus securing better stabilization. The penetration of wider portions of the screw into scalp is reduced, minimizing the scalp damage caused by the screws. Biodegradable and biocompatible PLA/PGA stoppers avoid intracranial migration of the fixation pins, especially in children.     

Is aggressive gap arthroplasty essential in the management of temporomandibular joint ankylosis?—a prospective clinical study of 15 cases

The purpose of this three-year, prospective, follow-up study was to evaluate whether aggressive gap arthroplasty is essential in the management of ankylosis of the temporomandibular joint (TMJ). Fifteen patients were treated by the creation of a minimal gap of 5–8 mm and insertion of an interpositional gap arthroplasty using the temporalis fascia. Eleven patients had unilateral coronoidectomy and 4 bilateral coronoidectomy based on Kaban's protocol. Preoperative assessment included recording of history, clinical and radiological examinations, personal variables, the aetiology of the ankylosis, the side affected, and any other relevant findings. Patients were assessed postoperatively by a surgeon unaware of the treatment given for a minimum of 3 years, which included measurement of the maximal incisal opening, presence of facial nerve paralysis, recurrence, and any other relevant findings. Of the 15 patients (17 joints), 12 had unilateral and three had bilateral involvement, with trauma being the most common cause. The patients were aged between 7 and 29 years (mean (SD) age 20 (8) years). Preoperative maximal incisal opening was 0–2 mm in 8 cases and 2–9 mm in 9. Postoperatively adequate mouth opening of 30–40 mm was achieved in all cases, with no recurrence or relevant malocclusion during 3-year follow up. However, patients will be followed up for 10 years. Aggressive gap arthroplasty is not essential in the management of ankylosis of the TMJ. Minimal gap interpositional arthroplasty with complete removal of the mediolateral ankylotic mass is a feasible and effective method of preventing recurrence.     

Temporomandibular joint internal derangement in mandibular asymmetry. What is the relationship?

The purpose of this study was to clarify the contributing factors and their influences on temporomandibular joint internal derangement (TMJ ID) symptoms in subjects with mandibular asymmetry. Postero-anterior (PA) cephalograms of 187 pre-orthodontic treatment subjects (aged 18-45 years, mean 23.9 years) were used to investigate the inclination of the frontal occlusal (FOP) and frontal mandibular (FMP) planes to determine vertical asymmetry. Mandibular dental midline shift (DMS) and mandibular midline shift (MMS) were studied to determine transverse asymmetry. The degree of asymmetry was analysed in conjunction with the results from self-administered TMJ ID history forms. A prevalence of TMJ ID was most related to the inclination of the FMP (P < 0.01), with the symptoms being notably higher when the cant was greater than 3 degrees. The symptomatic side was related only to the inclination of the FOP and FMP. Symptoms confined to the ipsilateral side were primarily found in subjects with mild asymmetry, whereas symptoms on both sides and those on the contralateral side were greater in those with moderate and severe asymmetry, respectively. No significant correlation was found for DMS and MMS. The results suggest that the degree of asymmetry in the vertical dimension is significantly correlated with TMJ ID symptoms.     

Outcomes of open temporomandibular joint surgery following failure to improve after arthroscopy: is there an algorithm for success?

We reviewed the results of one surgeon's experience of open surgical management of the temporomandibular joint (TMJ) in patients who fail to respond to arthroscopy and aimed to identify groups of patients that may or may not benefit from the intervention. Over a 7-year period (2005–2012) we retrospectively collected data from the medical notes of patients who underwent discectomy, disc plication, eminectomy, eminoplasty, and adhesiolysis, according to the clinical findings for joint pain, restriction, and locking. A total of 22 patients (71%) reported improvement in pain score and 19 (61%) reported an improvement in mouth opening 12 months postoperatively. Overall, 12 patients (39%) ultimately needed TMJ replacement. This group included 5/6 patients in Wilkes’ stage IV and 6/15 in stage V, 5/7 patients with a preoperative pain score of 90–100, and half of those with preoperative mouth opening of 20–29 mm (7/14). Open surgical management of the TMJ can benefit patients despite the previous failure of arthroscopy to manage pain, restriction, and locking. Arthroscopy seems to reduce the percentage of patients that need open TMJ surgery, but also the success of subsequent operations compared with previous studies. TMJ replacement is increasingly being done successfully to treat end-stage disease. These results may be used when obtaining a patient's consent for open TMJ surgery, particularly if they are in the groups considered to have a high risk of subsequently requiring a replacement joint.     

Changes in growth and morphology of the condyle following mandibular distraction in minipigs: overloading or underloading?

OBJECTIVE: Loading of temporomandibular tissues during mandibular distraction may cause changes in condylar growth and cartilage thickness. This study examines the effects of distraction on the condyle in a large animal model by explicitly measuring growth and in vivo loading. DESIGN: Unilateral mandibular distraction was carried out on 20 growing minipigs divided into three groups. One group underwent distraction but not consolidation, whereas the other two groups were allowed a period of consolidation of either 1 or 2 weeks. Animals received fluorochrome and 5-bromo-2'-deoxyuridine (BrdU) labelling and masticatory strain was measured from the condylar neck. Condylar strain was also recorded in an age-matched sample of eight animals that received no distraction surgery. Immunohistochemical procedures were used to identify dividing prechondroblasts and histological analysis was used to measure mineral apposition rate, count dividing cells, and measure the thickness of condylar cartilage. RESULTS: Strain magnitude, particularly compressive strain, was much larger on the non-distraction side compared to the distraction side condyle. Compared to normal loading levels, the distraction side condyle was underloaded whereas the condyle on the intact side was overloaded. Mineral apposition and cartilage thickness were greater on the distraction side condyle compared to the opposite side. Differences between the sides were most pronounced in the group with no consolidation and became progressively reduced with consolidation time. CONCLUSIONS: Increased mineralisation and cartilage thickness on the distraction side condyle are associated with reduced, not increased loading, perhaps because of disruption of the distraction side masseter muscle.     

Human histological research: is it necessary? Humane? Ethical?

A review of the dental literature in the United States over the past 60 years is replete with studies utilizing human histological evidence for research. The first reference found for the use of human tissue for histological study was published in 1941 in the Journal of Dental Research.(1) Much of this literature focuses on the use of block sections, in which teeth scheduled for extraction are removed along with portions of the surrounding soft tissue and bone in order to study the effects of various interventions. The tissue removed in no way facilitates the surgical extraction of the tooth. It is removed to establish the type of healing, repair, or regeneration by histological evidence. There is no compensating benefit to the patient who, in fact, is put at risk--the removal of the extra tissue may compromise the fit of a subsequent prosthetic restoration.     

Otologic symptoms in temporomandibular disorders patients: is there evidence of an association-relationship?

Several studies in the literature investigated the association between temporomandibular disorders (TMD) and otogenous symptoms, like vertigo, tinnitus, otalgia and muffling, although the question of the existence of a cause-effect relationship is still controversial. Epidemiological findings showed that the prevalence of ear symptomatology in the general population is variable from 10% to 31%, and increases up to 85% in TMD patients. Based on these data, many attempts have been performed to describe the physiopathological interactions between aural symptoms and TMD, as a strict anatomical link exists between the structures of the ear and those of the stomatognathic system. Unfortunately, methodological weaknesses of most studies are evident so that the comparison of results is often difficult. Considering these premises, the present study critically reviewed the literature on this debated issue, discussing the main etiopathogenetic hypotheses, the features of ear symptomatology in TMD patients and its relationship with TMD treatment in order to present current suggestions about the relationship between aural and TMD symptoms. Suggestions for future researches have been also presented, since a full understanding of this plausible interaction will be an important factor in diagnosis making and treatment planning for both pathologies.     

How reliable is your patient? A comparison of subjective complaints and clinical findings in a group of temporomandibular joint patients

A series of patients presenting for treatment for termporomandibular joint disorders was evaluated to assess the reliability of their subjective complaints. When compared with the findings on clinical examination, discrepancies were recorded. Limitation of mandibular movement, muscle tenderness and bruxism were more frequent clinically than would have been expected from the number of complaints, whereas temporomandibular joint pain and sounds were more common subjective complaints.     

Germectomy. The germ of the third mandibular molar in children: remove or preserve?

Third molars are often removed in order to prevent complications and various other problems associated with impacted third molars and their removal. Abortion of mandibular third molars is a procedure carried out at an early age in those subjects where there is insufficient room for the eruption of the third molars. On the other hand one can also decide to remove the second molars and to annexate orthodontically the third molars in the arch.     

Distraction of the temporomandibular joint condyle in patients with unilateral non-reducing disc displacement: Fact or fiction?

Objectives: This study investigated the distractive effect of a unilateral pivot splint on patients with unilateral disc displacement without reduction.

Methods: The study group was comprised of 18 patients who had no history of treatment with removable prosthetic restorations of molars, premolars, or canine teeth, and no previous treatment for temporomandibular disorder. Joint spaces measurements made on magnetic resonance images indicated the affected side to be narrower than the healthy side. Unilateral distraction splints were made for all patients. An ultrasonic motion analyzer was used to measure the vertical shift occurring on the affected side as patients closed their mouths with maximal force with the splint in their mouths.

Results: Closing with maximal force on the unilateral distraction splint led to a noticeable downward movement of the affected condyle.

Discussion: The findings of this study indicate that the TMJ condyle of patients with unilateral disc displacement without reduction may be unilaterally distracted if the articular space is narrowed.     

Diplomate of the American Board of Periodontology: is it in your future?

Periodontists who become diplomates of the American Board of Periodontology do so for many reasons. The intent of this paper is to explore the motivational factors of a select group of periodontists who have become diplomates. A survey questionnaire was mailed to 129 diplomates (1980-1984) asking them the question: "What motivated you to obtain diplomatic status in the American Board of Periodontology?" The answers from 95 diplomates were as varied as the individual respondents, but the principal motive was "personal achievement." This internalization for the need to become a diplomate was dominant over all external influences. Calculations made since January 1979 and the comments from the participants in this study strongly suggest that additional enticements must be forthcoming to draw more periodontists into diplomate status.