Impact of surgically assisted rapid mandibular expansion on the temporomandibular joint - A retrospective study

Transverse mandibular deficiency is, as in the upper jaw, a commonly encountered problem (Landes et al., 2008; Gunbay et al., 2009; De Gijt et al., 2012a; Gogna et al., 2020; Vinha et al., 2020). It is reflected in anterior crowding, transversal malocclusion, dental tipping, impaction of teeth and buccal corridors (Mommaerts et al., 2005; De Gijt et al., 2012a, 2012b, 2016; Nadjmi et al., 2015; Gül et al., 2018; Gogna et al., 2020; Smeets et al., 2020). Aligning teeth in these cases results in unaesthetic dental flaring with gingival recessions and a high risk of relapse due to a suboptimal occlusion since an upright tooth position in the center of the bone is lacking (Guerrero et al., 1997; Landes et al., 2008; Gunbay et al., 2009; Seeberger et al., 2011; De Gijt et al., 2012a, 2012b; Malkoc et al., 2012; Nadjmi et al., 2015; Pascon et al., 2016; Smeets et al., 2020). Dental extractions and interproximal tooth mass reduction could be helpful, but might still not provide adequate space in severe cases and as well have a negative impact on facial profile and buccal corridors (Guerrero et al., 1997; Landes et al., 2008; Gunbay et al., 2009; Malkoc et al., 2012; Pascon et al., 2016; Starch-Jensen et al., 2018). Widening the mandibular bone by means of Surgically Assisted Rapid Mandibular Expansion (SARME) is the most effective and reliable method to create enough space for teeth to be aligned (Guerrero et al., 1997; Kewitt and Van Sickels, 1999; Landes et al., 2008; Gunbay et al., 2009; Malkoc et al., 2012; Starch-Jensen et al., 2018).

Systematic reviews note that available scientific evidence with respect to SARME is still of low statistical power (De Gijt et al., 2012a; Gül et al., 2018). Statements are mainly supported by measurements on conventional 2D radiographs and/or cast models in small case series (N < 30) (Kewitt and Van Sickels, 1999; Mommaerts et al., 2005; Landes et al., 2008; Gunbay et al., 2009; Ploder et al., 2009; Seeberger et al., 2011; Malkoc et al., 2012; De Gijt et al., 2012b, 2016; Gül et al., 2018). This is why a lot of controversies remain about the surgical technique, the type of distractor to be used, the distraction protocol, and the spatial effects on both mandibular halves (Landes et al., 2008; Gunbay et al., 2009; Gogna et al., 2020). In addition, concerns have been expressed about the stress that might be imposed on the temporomandibular joint (TMJ) (Kewitt and Van Sickels, 1999; Stelnicki et al., 2001; Mommaerts et al., 2005; Landes et al., 2008; Ploder et al., 2009; Seeberger et al., 2011; De Gijt et al., 2012b, 2016). Mommaerts et al. (2005), developed a non-rigid bone-borne symphyseal distractor with a hinge mechanism in an attempt to avoid lateralisation movement of the condyles. Ploder et al. (2009), employed a cemented and screw-fixated tooth-borne appliance to minimize lateral displacement and rotational changes of the condyles. However, the impact on TMJ function is merely studied clinically, theoretically on dental or computerized models, or left to hypothetic consideration (Landes et al., 2008) with most studies assuming a lateralisation and/or distolateral rotational movement of the condyles, especially in tooth-borne appliances (Samchukov et al., 1998: Landes et al., 2008; Gunbay et al., 2009; Ploder et al., 2009; Malkoc et al., 2012; De Gijt et al., 2012a; De Gijt et al., 2012b; De Gijt et al., 2016; Gül et al., 2018). Up till now no attempt has been made to determine the actual 3D morphological changes of the condyles and to correlate this to the functional outcome of the TMJ (Stelnicki et al., 2001; Landes et al., 2008; Savoldelli et al., 2012; De Gijt et al., 2012a; Pascon et al., 2016). A first step has been taken by Stelnicki et al. (2001), who observed significant remodeling changes on CT scans in dogs after SARME with varying degrees of flattening, erosion and hypertrophy of the condyles at all contact points with the craniofacial skeleton. In this era, three-dimensional analysis has become inevitable and might further elucidate the “black box” of the condylar joint (Landes et al., 2008; De Gijt et al., 2016; Pascon et al., 2016; Gül et al., 2018; Starch-Jensen et al., 2018; Fan et al., 2019: Carvalho et al., 2019).

The aim of this retrospective, single-center study is to evaluate the impact of tooth-borne SARME on the TMJ function and condylar morphology, and to identify possible risk factors.

留言 (0)

沒有登入
gif