Wednesday, 1 February 2017

Hypodontia Study Day 2017



The Kings Hypodontia study day is being held on the 19th of April at Kings College Hospital. This course is aimed at trainees and specialty grades but is likely to provide some useful information to consultants involved in the management of the condition that may be looking at updating the evidence base for decision making. 

Important issues such as definitions and aetiology and the need for joint planning will be presented followed by management of the mixed dentition and orthodontic considerations. Towards the end of the day techniques in adhesive dentistry such as the utilisation of composite and resin bonded bridges will be described. The last presentation will review the need for implants and considerations when providing these. 

Information on registering and attendance will be provided on the below link. 

Monday, 9 January 2017

Do implants provide the best aesthetic outcome for patients with hypodontia ?


A study by Hvaring and colleagues has looked at the outcomes for patients with hypodontia and more specifically the treatment for missing teeth. They looked at a cohort of 50 patients with 6 missing teeth or more with a mean age of 26. These patients were examined clinically assessing mucosal discolouration, crown morphology, colour, and papilla index. 

Deciduous teeth showed good outcomes whereas implants had poorer results. Changes in gingiva colour was seen only for implants and occurred for all fixtures in the anterior mandible and the majority of those in the anterior maxilla. As you would expect papilla index scores were poorer for implants and conventional bridges when compared with orthodontic space closure.

A pubmed link to the paper is below 


Implants are a popular treatment modality in the management of patients with hypodontia as they provide tooth replacement without the need for adjacent tooth support or retention. Over time those working in the hospital services have seen case from 5 years or more return with either mechanical or biological complications. Patients with hypodontia may have adequate bone stock around the top of the ridge but this becomes more compromised higher in the alveolus. Over time the alveolus is likely to continue to resorb as illustrated in the above research resulting in mucosal discolouration due to the slow exposure implant threads. In such patients, who have such underdeveloped ridges, alternative tried and tested treatments maybe wiser to consider. Resin bonded bridges are predictable, efficient with good long term outcome data. Consideration for the patients long term maintenance-especially if treated in late adolescents-needs to be a significant consideration. 

Wednesday, 19 October 2016

What congenital anomalies do patients with Downs Syndrome present with ?





A low powered study from Brazil has illustrated some evidence for hypodontia being highly prevalent amongst patients with Downs Syndrome. In this study 96 individuals were clinically and radiographically examined. 

Hypodontia was found to be the most prevalent condition at 36%, followed by microdontia at 10%, conical teeth at 7%. Taurodontic teeth were rarer at 3% with other anomalies such as dens invaginatus 1% of cases. 

The authors concluded that the occurrence of hypodontia was high amongst this patient cohort and is likely to impact on their management not only in their interaction with orthodontics and paediatric dentistry but also with special care dentists managing them in adulthood. 

The link can be found below

http://www.stephenhancocks.com/download.php?op=view_article&article_id=395

Thursday, 1 September 2016

Is there a link between ovarian cancer and hypodontia ?

A systematic review by Iavazzo and colleagues revealed a possible link between ovarian cancer and hypodontia although the research associated with this was very weak at best.

In total, 385 patients were included in this study. Control group was present in 3 out of 4 studies (340 patients). Hypodontia was present in 20%. Only in 2 out of 4 studies, the number of missing teeth was mentioned (47 teeth), while the majority of them were either maxillary second premolars or maxillary lateral incisors. 

Unilateral distribution of the missing teeth was present in 28 out of 46 patients, while bilateral distribution of the missing teeth was present in 18 out of 46 patients. The presence of ovarian cancer in the family medical history occurred in 12 out of 33 patients. Only 1 out of 4 studies examined the presence of genes with mutations in the included patients. Based on these findings, the lack of clinical studies was the principal obstacle to clarify the possible predictive value of hypodontia in the early prediction of patients with higher risk of ovarian cancer.

Tuesday, 26 July 2016

New evidence shows patients prefer closing spaces versus opening spaces when teeth are missing




Qadri and colleagues have surveyed lay members of the public to try and measure their perception of different types of orthodontic treatment and subsequent restorative treatment. Opening of lateral incisor spaces can be difficult to get right especially if there are other complicating factors. The closure of spaces obviously has its advantages. It removes the need for ongoing maintenance of a restoration such as a resin bonded bridge, this can be even more complicated and involved where implant restorations are planned in these sites which will potentially need grafting and long life maintenance...lets not mention the potential for complications ! 

Other issues to consider with space closure include the gingival profile of the canine, the depth of colour of the canine and its size and ability to be disguised with bleaching and bonding as a lateral incisor. In this research from a group in Sheffield (UK) they found that patients and laypeople preferred space closure from an aesthetic sense as opposed to having a restoration in the lateral incisor position.    


LINK TO ABSTRACT

Sunday, 1 May 2016

Dental management of Rapp-Hodgkin syndrome associated with oral cleft and hypodontia

Rapp-Hodgkin syndrome (RHS) is a rare type of autosomal dominant disorder characterized by association of ectodermal dysplasia (ED) with cleft lip/palate. The main features include dry, brittle hair with alopecia in adulthood, dental anomalies (hypodontia, microdontia with delayed eruption, fissured tongue, and retruded maxilla), hypohidrosis, dysplastic nails, and clefting. Palmar-plantar keratoderma is seen frequently. RHS has signs and symptoms that overlap considerably with those of ankyloblepharon-ED-clefting syndrome and ectrodactyly-ED-clefting syndrome. 



The below link takes you to an article that discusses a case of RHS, one of the four members in three generations who had ED with variable degree of involvement of hair, teeth, nail, and sweat glands.


Rapp-Hodgkin Syndrome

Friday, 12 February 2016

Kings College Hospital Hypodontia Study Day on 4th of May 2016



The annual Kings College Hospital Study Day will take place on the 4th of May 2016 at the Weston Education Centre, Denmark Hill. The program will be delivered by staff of Kings who are directly involved in management of both adolescent and adult patients on a number of multidisciplinary clinics. Subject covered will include management of the developing dentition, orthodontic considerations, the provision of adhesive dentistry such as composite masking and resin bonded bridges in addition to the placement of implants. 


Saturday, 6 February 2016

Gremlin gene associated with Hypodontia ! Yes Gremlin !

As a child of the 80's I loved the Gremlins films as well as Back to the Future Indiana Jones etc. So it turns out that there is a Bone Morphogenic Protein antagonist that is known to regulate BMPs in embryogenesis and tissue development. Have a look at the abstract of some research by a group from Thailand.  

Gremlin 2 BMP

Friday, 8 January 2016

Certain genes are related to certain patterns of missing teeth

I could never profess to knowing anything about genetics in any great detail ! In this graphic the two main genes in Hypodontia are illustrated. MSX1 shows a significantly different pattern of tooth loss to PAX9 which is heavily associated with the commonly missing lateral incisors and premolars. Have a read of the below article for more information.